Transcript for:
High-Yield Anatomy Review

[Music] okay just let me know if the AB is fine and uh we can get started and all that I have have no idea So we are all we don't know what's going to happen uh so let's prepare for the worst even if the exam is there which even I I I I believe that I also would advocate at least for the people who are living for the people who are living close to the border So I would say it should get postponed but we should we should be preparing for it Yeah admit card People have traveled to the centers and still it got cancelled So that is not a big deal Okay Okay guys welcome all of you So uh let's get started As you know these sessions are a little longer So I think we should not be taking up any time further Last time we started I guess we just went with the first two slides and it got stuck So I I will start it again from the beginning itself The sequence would be that I'll be starting with the embryology followed by I'll be going to the limbs and then head and neck neuro and uh abdomen part and hisystologology slides kept in between because you know it gets a little monotonous if you read hisystologology at one go only So like couple of slides in between between head and neck and neuro between neuro and abdomen like that So that's how we're going to approach it Needless to say you people are attending this one short session from last one week I'm sure it will be very exhaustive But I'm very sure that it will be very productive also because in the shortest span of time you can cover up almost all the important things So uh it's little unfair to ask this question that is one shot enough Well enough is not enough in itself But yeah I mean you you have to the one shot will at least comprise of all the topics which you cannot leave and go to the exam you you have to go through this and while formulating this PowerPoint for you we I obviously I have kept in mind that what are the recent questions which are being asked and how they can kind of uh you know twist the language of the question so I'll kind of discuss that about in between these you know um what do you say during these lectures it's it's quite u uh and during these lectures this is it's a little difficult to kind of keep a track of of what live chat is going on because there too many people message me in between So I'm really sorry if I miss any message in between but um I I will tell you the way to communicate to me so that even after the one shot you can you can we can still stay in touch and I can clarify your doubt So let's get started So guys in the embryology let's first start with the this section of the embryionic embryionic plate which which has been asked already in twice in the exam last year and even last to last year they asked this question So um you know there are certain questions in anatomy which are very terminal questions Once they ask that question that's it end of it what is a nerve supply of the following muscle once they ask this question this question is over or about any branch of any artery or something like that but obviously there are certain topics which are not going to end at that point for example when you look at this picture there's so much to ask on this they have already asked the questions on neural crest cells and paragal misodum but this image is at least holding like 20 more questions inside so they can again put this image in front of you but obviously the question is going to change So what you're looking at you're looking at a cross-section through the neural tube What you can see the three germ layers there Endodm ectodom and misoderm That light green colored structure that you see over there is a notocord Notto if somebody ask you nottoord is made up of what It is made up of misodum But what misodum It's a ex axial misodum Please listen to me carefully It's exial misodum not parexial Exial midline misodum thickening is forming the notto cord What cord is going to do guys Notocord is going to stimulate the ectodom and convert the ectodorm into neuroacttodum and then the neuroacttodum folds to form the neural tube As you can see the neural tube there and we do have the cells which is present at the junction of the neural tube and ectodom These are called as a neural crest cells Well which is also called as a fourth germ layer the neural crest cells And in the electron microscopic image you do not expect to see the neural crest cells better than this Reason being neural crest cells are derived from the same neuro ectodom only from the crest of the neural fold itself So there is no visible difference between them So what I'm trying to say that if they ask you the derivative of the neural tube they will make sure that the arrow is placed on the neural tube But if the arrow is placed somewhere at the junction of the neural tube upper part of the neural tube and the ectodom then obviously they're asking about the derivative of neural crest cell I tell you this because when this question was asked couple of years back in the exam many people thought they're asking the derivatives of neural tube Well why would they do that Why If if they want to ask the neural crest cells they will put the arrow at the junction Otherwise they put there's a big neural tube You can put the arrow anywhere At the same time when the neural tube is being formed this misorum is going to divide in three part That is a paraxial misum We have a intermediate misum which is in between and we got a lateral plate mison And this lateral plate misum is further going to divide in two part that is into the uh the somaturic lateral plate misorum and splanknopluric lateral plate misum that I'm going to tell you about here Uh just one quick thing in between guys how many questions from anatomy honestly nobody can define that this is this is very unfair to say that how many questions from that particular topic because it's it keeps on changing it's very dynamic I would say INIC that is more concentrating into anatomy especially the embryology and neuronetry part compared to the need exam but guys I mean who knows better than you people that you cannot just afford to miss out any of on any of the subject here so it is as important as any other subject and it goes the same for all the 18 subjects So just don't worry about the number of questions The point is how many percentage of question I'm going to get it right Thus question I b question I your your you know strike rate should be above 80% in the anatomy I mean and and because there's no big science behind it The very you know these topics are being asked over and over again People don't realize them because it's the same thing It's the same thing which they quote in the different you know in the rapper and then gave it to you Otherwise what could be new in anatomy It's the same subject which was like 50 years back the same anatomy today So nothing changes It's just the language of the question is twisted so dramatically It looks like a new question every time It's never new It's always the same thing which is being asked You just have to be little smart enough Okay So guys back to the topic So what I was saying now look at the intermediate misumo first Now that small part in between is intermediate misum You don't even realize that it's intermediate misum to be honest So that that's why I believe that if they're asking a question on intermediate misodum I'm pretty sure that they're going to highlight it and show it to you because look at the other side here Can you identify where is intermediate misum Well very difficult right paraxel misodum and lateral plate misum we already saw It's very easy to identify them here Now as you can see that intermediate misodum first of all the intermediate misodum is going to give rise to the eurogenital system Now I'm going to talk about this eurogenital system in a while but when I say eurogenital system what I'm talking about I'm talking about gonads like testus and ovary and misunafric duct and parameric duct So all the eurogenital system it is heavily contributed by the intermediate misorum So let's keep this intermediate misorum aside for now As I said it will give rise to genital ducts It will give rise to the misonic parameric duct the derivatives We'll come to it We'll come to it Forget about it for now We focus on paragial and lateral plate misodum because if you know the paragal misodum you automatically know about the lateral plate misodum The paragal misodum it will give rise to the ball-like condensation along the entire length And those ball-like condensation are called as somites I'm sure you have heard the word somites or somatic The sommites are the ball-like condensation As you can see in the center guys that is let me just put a laser pointer there If you look at that this is the neural tube here in the center Can you see this That's a neural tube It's a cranial neuropore above That's a cordal neuropore Below that's a neural tube And on the side of the neural tube that is a paraxal misodm And these thickening of the paragal misodm are called as somites Even if it's an image based question I'm sure you'll be able to identify it like this only These are called as somites What are the derivatives of somites And when you think of derivatives of somites you also need to keep an eye on what is not derived from sommites because whatever is not derived from sommites will be derived from lateral plate misulum So it's very easy You can compare the paragular lateral plate with each other Now guys sommites can be dividing into three part We have a dermatome sclerot myo that like dermatome part of the somite will give rise to dermis but dermis of only back only back dermis is derived from it here Exial skeleton Exial skeleton that is ribs and vertebrae Ribs and vertebrae is derived from the the the somites only and ribs was one of the question asked in the recent time guys Last year question was ribs only the ribs is derived from which of the following mar structure and that was paragal misum or somite is the answer to that and it will also give rise to the skeletal muscle but remember guys when I say skeletal muscle we are talking about skeletal muscle elsewhere in the body but majority of the skeletal muscle in head and neck are derived from ferangel arches I'm sure you know this What is the specialtity of the head and neck Developmentally the head and neck specialtity is that the skeletal muscles like mastication muscle facial muscle pallet fairings larynx all these muscles are derived from fingial arches Only extracular and tongue muscle especially tongue muscles they are derived from sommites But when you think of rest of the body upper limb muscle intercostal muscle abdominal muscle pelvic muscle lower limb co muscle all muscles are derived from sommites only So the thing is that if dermis of the back exial skeleton and skeletal muscles are derived from the somites So whatever is left is derived from lateral pisodum Now whatever is left now think about first make a list in your head what is left What is left guys We still have to form the dermis of the front and dermis of the limbs Number two we have to form the what muscles Smooth muscles and cardiac muscles Right Smooth and cardiac muscle And we also need to form what skeleton Appendicular skeleton Exel is done Upper limb and lower limb bones are to be derived here And that will be derived from where Lateral pate misodm But here's the catch Even in lateral pate misoderm I hope can you appreciate if I if I show that laser pointer there Can you see that over there Guys please look at the screen here There's a cylum over there that is called as a intrambbriionic And that intrambriionic d divides the lateral blade misorum into the somatloric layer and the splankuric layer So the one above is somatopluric lateral plate misodum and the one below is splanknopluric lateral plate misodum So we already know that what is derived from lateral plate misodum The question is which one is from somatopluric and which one is from splankno Somatopluric lateral plate misodum will give rise to the dermis What was the dmis left guys Dermis of the front and limbs and what skeleton appendicular skeleton Upper limb and lower limb bones are derived from here Whereas plank pluric clatter plate misodum will give rise to what It will give rise to the what muscles smooth muscles and cardiac muscle Although cardiac muscles are derived from the cranial end of the embryo it's a specific site for that But yeah at least I can broadly I can say that the cardiac muscles and sk the smooth muscles they derived from the spinoplloric lateral plate miso Okay see you asking me the highlight the topic for the ionic city need It's pretty simple embryology and head and neck I would say even because neuron anatomy is equally important for both knee and IC but but embryology and head and neck INSD love to ask question from there and nerve injuries guys peripheral nerve injuries here and rest whatever we're discussing in one shot everything is important rest is like it's more focused toward the the neat part here but you know I would sincerely suggest you that especially when the content is squeezed to 5 hours or 4 and 1/2 hour thing I don't think that you should be doing more selections in between that like you at least one you cannot leave anything from this this If there is anything additional I I'll let you know Okay Moving on So intermediate misum just keep it aside And the paraxel and the lateral plate misum that you need to compare Now guys you might be having this PDF with you Now I requested this to you last time also and I'm again sincerely requesting you please close it disclose that folder or file or whatever that you have or if you have taken the Xerox or that just keep it aside because if you're looking at the slides already you're not going to anticipate anything I want you to please anticipate what is going to come next and that's why it's very important to keep your mind blank look at the picture and that's how you can fall back to your notes that what we read and how can we correlate here then it will not be you know you will not be able to anticipate what is going to come next sir moving on now we talked about the misodum the parexel intermediate and lateral plate misodum Now as we said noto cord will give rise to neural tube Notocord will is going to stimulate the ectodorm to form neural tube and neural crest cells Now what are the derivatives of the neural tube and neural crest cells and moreover what about notoord cord job is done So once the noto cord job is done some remnants of noto cord are there and those remnants are present in the midline of the body When I say midline of the body guys there is one called as the apical ligament of dense Dense is a second cervical vertebrae orid process Second cervical vertebrae extension is called as dense So there's epical ligament of dense There is uh nucleus pulposis I'm sure you know that intervertebral disc can be divided into two part is nucleus pulposis So nucleus pulposis and number three is membran tector or tectoral membrane Membran tector or tectoral membranes Look at the laminate here So not job was to stimulate the ectodorm to convert it to neuroacttodorm butaka whatever is left from the that is nucleus pulposus epical ligament and membrane tetori tectoral membrane I would say out of these three especially nucleus pulposus is the most important but which I feel personally that nucleus pulpos that is the one that is usually given in most of the books and rest two are also the remnant but they are not usually they don't talk about them nucleus pulposus is the most important remnant of the of the Notocord What about the neural tube and neural crystals Now when you think of the neural tube derivatives guys in the neural tube derivatives just think about the central nervous system CNS central nervous system If you're able to correlate that structure that you're looking at with central nervous system then means you're thinking right now look brain and spinal cord obviously central nervous system oligodendrittes they will do mileination for central nervous system Astroytes forming bloodb brain barrier Appendama What is epidemma guys Lining of the ventricle is appendma Retina Retina is an extension of the optic stock only So if you look at that list over there that is all about the central nervous system or the supporting cells of central nervous system So they are all derived from the neural tube What about neural crest cells When you think of neural crest cells see the the easy way to deal with the neural crest cells Though not everything will be covered in that But still when you think of neural crest cell majority of the derivatives of neural crest cells can be answered by thinking about two two thing One peripheral nervous system If you can correlate that given option with a peripheral nervous system it is definitely derived from neural crest cell Peripheral nervous system means ganglion or nerves or the milein sheath or whatever Okay And number two the structures which are present in head and neck and they look misodermal Now please understand majority of the structures in head and neck which looks misodal to you for example bones what do you say the the dermis and the dentine anything cartilagages which but if they're present in head and neck there are very good chances that they're derived from the neural crest cells Now while looking at the option if you're able to convince your brain that the given option is either belonging to the peripheral nervous system or this structure belongs to head and neck and looks misodermal that means you're looking at neurotr derivative that's a very good chance in that look at that when you say all ganglion gangon any ganglion whether it's a sympathetic parasympathetic gangon sympathetic chain otic ganglion dorsal lute ganglion whatever it is if the name says ganglion it is derived from neural crest cells probably The only misnomer here is a basil ganglia because basil ganglia is not a ganglia it's a nuclei entry plexus myntric plexes misnner plexus orex plexus they're all from the neural cryst cells cells mileination swan cells will do the mileination for peripheral nerves adrenal medula I hope you know adrenal medula is having the chromophil cells and these chromophil cells are nothing but the modified sympathetic ganglion only modified sympathetic ganglion look at the word when I'm saying ganglion melanoblast look at the skull bone guys most of them Some exceptions are there but most of the skull bone except the occipital bone is coming from the somite Then dentine inferial arch cartilage dermis of head and neck conotal If you look at the these this this these derivatives here they look misodermal but they're in head and neck So that misenime of that head and neck is actually derived from neural crest cells only So despite there's a there's a very long list of neural crest derivatives zani peripheral nervous system or just go with the the what do you say the headenic structures which look neural to you moving on okay that was about this that picture guys and the derivatives I believe that's very important juncture and from where the questions are still yet to be asked question that section of the embryo and the derivatives from there can still be asked in the exam very good chances and especially INIC because they love to repeat the topics okay development of diaphragm diaphragm development I'm pretty sure that you must have seen these questions multiple times at different places now diaphragm is derived from four sources it's important to identify those sources or those structures on the picture what you're looking at right now look at the posterior lateral guys it's a developing diaphragm so don't try to relate this diaphragm with a with a actual gross anatomy developed diaphragm it's a developing diaphragm so what you're looking at there is a body wall misorum now Body wall misorum which is like right now in the picture can be seen posterior laterally What is body wall misorum It's a cervical somites only It's a misorum It's it's a paragal misorum only Cervical somites or body wall misorum and that will give rise to the muscles of the diaphragm Muscular part of the diaphragm will be derived from this body wall misorum or you can say cervical somites Second thing is a dorsal misentry of esophagus Now esophagus is not having any misentry Misentry misentry is with the stomach Misentry is with the intestine Misentries with a colone misentry is with a sigmoid colon appendix But there is no misentry esophagus There was there was misentry fophagus also And that dorsal misentry esophagus is absorbed to give rise to the crust of the diaphragm or you can say cr of the diaphragm The crust or the crer of diaphragm is by the dorsal misenterophagus Number three septum transversum The most important septum transversum is the most cranial structure in the embryionic plate before the folding of the embryo And once the embionic folding takes place the septum transversome will come like more in the front area here So in the developing diaphragm the most anterior structure that you're looking at over there that is septum transversome Although it will give rise to the central tendon of the diaphragm which eventually will go toward the central part here That's a central tendon coming from septum transversum And look at the dark pink color over there guys That is called as a pluroparonial membrane It's a thin membrane which is separating the plura and perodonium We call it a pluroparinal membrane Now this pluroparital membrane now there are two fades to it Number one the pluroparital membrane is formed but this pluroparital membrane is not incorporated by the muscle The muscles are not going to invade this pluroparinal membrane and that failure of the migration of the muscle into this into this pluroparital membrane that will cause this membrane to stay very very thin and that is called as a eentration of the diaphragm One condition is that pluroparital membrane is not present If pluroparital membrane is not present if it it is absent completely then it is going to give rise to the opening and that is a bog leg opening or bog legin and that is congenital diaphragmatic guys I'm sure you all know about congenital diaphragmatic which is more common toward the left side and that is basically because of the uh this absence absence of the pluroparital membrane we said there is a second condition the pluroparital membrane to this pluroparital membrane is not invaded by the muscles it is not incorporated by the muscle if the muscle fail to incorporate this then a thin membrane will be there which is separating the the thoracic cavity and the abdominal cavity and that still is not able to stop the intestine to coming into the thoracic cavity that is the ventration of the diaphragm the ventration of the diaphragm they've asked this question about the pluroparital membrane absent multiple times I very strongly feel they can ask you the question like this that pluroparital membrane is present present to here but it is not incorporated by the muscle then what condition it can give rise to that is e Ventration of the diaphragm event paraphr we'll come to that we let's reach there you know eventually okay point fangel arches now fangel arches if in the entire embryology guys if I have to suggest that you just want to kind of revise you know you want to revise embryology and there is a choice given to you want to revise only one topic in embryology please go with this this close your eyes and just go with the fangial arches everything about fangel arches This is important I can keep this topic as the as as a topmost priority in the anatomy that is fangial arches But when I say fangial arches it's about everything Ectodorm endoderm misorum fangial arch arteries Everything about fangial arches is important Okay Now what you're looking at right now you can see 1 2 3 four and six arch Needless to say fifth arch disappears And I hope you are able to appreciate that there is a the red color which is shown on the inside that is the endodorm And the green color on the outside is showing the ectodorm And then obviously the orange color inside basically showing the misodorum You can see that that second ferangel the ectodomm of the second fangel arch is overgrowing and that ectom of the second fangel arch it's if I may it overgrows like this and will go down and come below and that's how it leaves a embryological space over there which is called as a cervical sinus The cervical sinus all the cliffs are closed guys All the spaces on the outside are closed So second cliff third cliff fourth cliff clif the clifs are not there and the space is called a cervical sinus The cervical sinus eventually disappears But if the cervical sinus persist I'm sure you all know that it can give rise to the brink cyst That can give rise to brink cyst That usually it's a painless harmless swelling that we have along the sternocltoid mastoid That is a the brakill cyst The only clift which is left is the first one First cliff is the only cliff we have And that first cliff I mean look at the head and neck guys The only opening that we have on the side is the external audiary canal So first clift is the only cliff we got and that is going to give rise to the external audiary canal and even the outer layer of tempanic membrane Outer layer of tempanic membrane Now some new you know updates are also there in this that it's not just the first cleft even the first fangial arch first arch also contributes to the external audiary canal Right So I'm just saying let's say if they want if if first cleft is given in the option please go with it But if first cleft is not given and first arch is given in the option you can also go with that as well It is mentioned in the latest langu as well that the first cleft and even some part of first arch also contributes to the external audiary canal and the outer layer of tempanic membrane the space on the inside that is endodmal spaces I'm sure you all know that those endodmal spaces are called as what pouches as you can see the first pouch which lies between first and second arch Well what this will give rise to it's quite easy If the first clif is giving rise to the outer layer of tempanic membrane and external audiary canal the first pouch will give rise to the inner layer of tempanic membrane and just go from there only like inner layer of tempanic membrane is facing toward the middle ear cavity and the two extensions of middle ear cavity are ustian tube and mastoid antrum and they both are derived from the first pouch So inner layer of tempanic membrane tempanic cavity auditor tube and mastoid entrum The second pouch the second pouch will give rise to the palatine tonsil Although it is believed that the lymphoid present in the palatine tonsil is derived from neural crest cells If they want to ask this in more detail push peline tonsil is derived from second pouch that is correct But the lympoid present in pelatine tonsil is actually derived from neural crest cells Third pouch guys Third pouch is the one which is which is quite important I would say based on the question asked in the recent time Third pouch will give rise to the thymus and inferior parathyroid gland Whereas a fourth pouch will give rise to the superior parathyroid gland here That that sounds a little opposite here But superior is from fourth pouch and inferior is from the third pouch here Fifth pouch we do not have fifth pouch because the fifth arch disappears So we do not have fifth pouch but we have some remnants of fifth pouch which are called as a ultim brink body And that was you were talking about Abhishek that ultimate brinkle body is the one uh it is basically ultimal body is invaded by the neural crest cells and that is the one which is going to give rise to the the parapholicular C cell So if the question is asked to you that C cells are derived from where definitely neural crest cell is a better answer than ultimal body I'm sure you also read about this in your pathology also that third pouch and fourth pouch anomaly guys the micro deletion syndrome the DG syndrome So if and this was a this was one of the image based question asked that if there is a absent or if there is a mal development of the third pouch and fourth pouch also especially third pouch then it can give rise to the djord syndrome that is absent thymus and hypoparathyroidism guys djord syndrome the micro deletion syndrome like 22q1 that is delion syndrome that is the djord syndrome right okay so that is about the cliffs and pouches cliff only first cleft is there pouch all of them there and then you're looking at the derivatives of all these pouches here Okay moving on to the fangial arch cartilages Now now it's it's it's a picture that you need to keep it in your mind Obviously it's not easy to remember everything in the exam You just have to keep this picture in your mind guys First arch Now there is a cartilage that you see in the first arch This highland cartilage model is called as a mechel's cartilage Mckel's cartilage And this mech's cartilage is the one which is a cartilage of first fingial arch But Mckel's cartilage gives rise to what It gives rise to the malus and incus I'm sorry Let me go back The mechel's cartilage is the one which will give rise to the malus and incus Mckel's cartilage is not giving rise to mandible Mandible is derived from first arch That is true But that is not derived from mel's cartilage guys Mckel's cartilage to highland cartilage Highland cartilage will oify and give rise to the bone And majority of the skull bones are not derived from the cartilagages because they are from the membranous ocification The flat bones flat bones will be from membranous ocification So it is right to say that whatever derivatives we have from Mckel's cartilage is derived from first arch but not necessarily every derivative of first arch is coming from mel's cartilage So simple about first arch that orange color over there first arch will give rise to mel's cartilage and the bones coming from there is malice and incus like from the mel cartilage itself second arch will give rise to stapes I'm pretty sure that you all know about this this exception also that stapes except the foot plate of the stapes the foot plate of the stapes and annular ligament they are derived from the otic capsule they're derived from the otic capsule so it's the it's the stapes that is correct but not the foot plate of the stapes remember that here rest everything is fine guys styloid process is stylohy ligament lesser cornoa small part of the upper body also it is all coming from second arch the blue color is for the second arch here third arch will give rise to what the greater corno of the hybone and the lower body of hide this lower part of body and the greater corner of the hidebone it is derived from the the third arch and fourth and sixth arch fourth and sixth arch collectively are giving rise to langel cartilages the reason I keep recommending that that don't do them separately because every book is having a different opinion on that so I would that whether it is thyroid criccoid whatever all the lenel cartilages are derived from fourth and sixth arch collectively collectively from fourth and sixth arch that is len cartilage Yes question recurs cartilage I mean second arch cartilage first arch cartilage is mel's cartilage second arch cartilage is called as recurs cartilage and that recurs cartilage is the one which will give rest to the stapes and styid process styohhide ligament so you're right okay fangial arch arteries now talking about fangial arches how can we miss the fangial arch arteries guys so I'm sure that many of you attended my class so you probably remember it it's a recap so but for the recap I need to first tell you take you to the basics of that here guys to understand the fangial arch artery see in the developing embryo we have two dorsal iota iota there are two dorsal iota so we have a right dorsal iota and we have a left dorsal iota you are looking at the two dorsal iota right and left dorsal iota guys please look at the screen please don't look into your notes because you will see every step happening here and that's why I want to please focus on the screen here then dorsal iota is present on the dorsal side more ventrally in the developing thoracic cavity more ventrally we have a heart tube and the cranial part of the heart tube is called as a truncus arteriosis I hope you all remember that word guys Truncus arteriosis The truncus arteriosis is having an extension and that extension is called as a iotic sack And that iotic sack divides into the right horn and the left horn of the iotic sack That's looking at the iotic sack there And there is a right horn and the left horn of iotic sack right and the left horn of iotic sack They need to connect to the dorsal iota And how do we connect them to the dorsal iota By fangial arch arteries How many fangial arch arteries How many fangial arches we have We have six fangel arches initially Fifth one disappears but initially we have six fangel arches and that's why we have the six fangel arch arteries which are connecting these two horns of the iotic sack to the dorsal iota So that's the that's the first second third fourth fifth and the sixth fangial arch arteries One more important thing we need to know before we go to the arterial development There are multiple branches coming out of the dorsal guys I mean branches like we have here here here here like this But there is one which I need to focus on and that is the seventh cervical intersegmental artery Whether it's on the right side or left side there is something called as a seventh cervical intersegmental artery Why the seventh one is so important Because seventh cervical intersegmental artery will go into the upper limb It will become subclavon axillary and then eventually brachial radial and everything That's why the seventh one So all I'm trying to say that seventh is not the only artery we have We have other arteries also above that and below that But the seventh one you need to focus on seventh cervical intersegmental artery It has some role to play We'll come to that So I hope you understood this image here Now let's take this picture Let's take this picture Uh Sudanchu I I I'm not going to go English on this because you know many of our friend are attending this session from very southern part of the country and probably they're not comfortable in Hindi So let's go in English But basically English it's very simple English I'm speaking you right So that is the iotic sack and we have the right and left horn of iotic sack Right Once again now first let's start with the arch of iota When I talk about the iota guys iota or arteries it's iota is toward the left side and vinas are toward the right side So when I say left side it's the right side fourth arch artery which is the most important Dorsal iota is also there but I know that in the exam they will just ask you that which arch artery is going to give rise to the uh to the to the what do you say to the arch of iota So simply the left fourth arch artery but please make sure that don't do not you know miss out on the right and left it's left side fourth arch artery overall overall the arch of iota is derived from where iotic sack is there left horn of iotic sack left side fourth arch artery and some part of dorsal iota also that's a left dorsal iota as well but still you just stick to the fourth archery the left side I'm I can assure that is more than enough left fourth archery arch of iota okay of the arch branches What are the branches of archoproofota We have three branches guys One we have the uh what do you say the subclavian artery with subclavon that is the right subclavon artery Then we have uh sorry brachiophilic arter I'm sorry brachiophilic artery Then we have the left subclav artery and the left common corroed artery Subclav artery you can already see guys look at that if I may point it out that already is there This is the brachosophilic artery I keep saying subclav I'm sorry that is brachiohelic artery That's the brachioiphalic artery and that is derived from the right horn of iotic sack That's it Right horn of iotic sack is going to give rise to brachioelic artery Okay What about common carroted Common carroted arteries derived from third arch artery Now first look at that guys Can you see third arch artery and then there's a bud coming out from there That is the external caroted artery Now this here is the common caroted artery That bud is for internal external carroted and the remaining is the internal carroted artery So it's not wrong to say that whether it is common carroted internal carroted external carroted artery which arch artery is forming third arch artery exam may say arch artery pushing they will mainly ask you about the arch artery So focus on that which number which arch artery is that here So whether it is right side or left side the common corroted artery is by the proximal part of third arch artery and internal coroted artery is by the distal part of third arch artery Okay then let me bring that seventh cervical intersegment I hope you remember seventh cervical intersegmental artery Now guys this left side seventh cervical intersegmental artery will give rise to left subclav artery Left side seventh cervical intersegmental artery will give rise to the subclav artery And that completes the branches of archopota Let's focus on archota So three branches of archota there What three branches are we talking about guys One branch of archopert is there that is a brachiohelic artery coming from where Right horn of iotic sack Then another branch of archoperta is common cored artery of the left side Obviously that is coming from third arch artery And then we have a subclavven artery of the left side which is coming from seventh cervical intersegmental artery Right That is sorted But the main question here is what about the right subclavven artery guys What about the right subclavon artery The right subclavon artery is by the seventh cervical intersegmental artery That is fine but we also need the fourth arch artery there Fourth arch artery on the left side is forming the arch of iota right side where there is no arch of iota but fourth arch arteries there So I can use that fourth arch artery also along with seven cervical intersegmental artery Now they both together will give rise to the right subclav artery Now just repeat this after me I mean to yourself only Right subclav arter is mainly derived from where It is by the right side fourth arch artery and seventh cervical intersegmental artery Dorsal be dorsal is also there in between but that major part is by fourth arch artery and the right seventh cervical intersegmental artery Right Okay Then there is a development of lung buds You can say lung buds or respiratory buds Guys lung buds and respiratory buds are the one which are invaded by the sixth hour charter Look at that sixth hour charter is invading the lung buds And that tells you that the proximal part proximal part of the sixth arch artery will give rise to what Pulmonary artery Proximal part of sixth arch artery will give rise to the pulmonary artery Distal part of the left sixth arch artery very important and a question asked in the exam recent time Guys look at this distal part of the only left side only left side not on the right side Distal part of the left sixth arch artery will give rise to the ductus arterio So it's very important structure obviously in the fetal circulation Ductus articulus is derived from from the distal part It's very important to say the word distal D distal part of the left sixth arch artery will form the ductus articulus Fifth arch artery disappears Now we all know guys that the fifth archer this fifth archery disappears So forget about it What about this first and second arch artery I'm sorry The first arch artery remnant guys The remnant of the first arch artery is the maxillary artery and the remnant of the second arch artery is the hyoid and the stipidal artery Just this remnant only first archer remnant is maxillary and second and second arch artery remnant is hyoid and stidil artery These are embriionic arteries only to but just give it a calculation guys First arch artery over there you can see that is that is the maxillary Second arch artery here is stipid and hyoid Third arch artery is forming common caroted and internal keroted external also Fourth arch artery is forming arch of iota and right subclavon Fifth arch artery hein forget about it And the sixth arch artery will give rise to the pulmonary artery and ductus arteriosis Ductus arteriosis Okay There's a question asked about the recurrent langel nerve Now if you look at the left recurrent langel nerve the left recurrent langel nerve is longer because it hooks below the sixth archery You can see the left recurrent lenial nerve is quite long because it hooks below the sixth archery And this sixth arch artery will persist even after birth in the form of ligamentum arteries Ductus arterius will close but ligamentum arterism will be there So it is still will be there But what on the right side On the right side the recurrent langial nerve it hooks just below the fourth arch artery Look at the on the right side because the distal part of the sixth arch artery is not there and fifth arch artery is also not present And that's why the right recurrent langel nerve because it is just hooking below the fourth arch artery it is shorter So it's very important to know that the recurrent langial nerve of the left side is longer because we have the sixth arch artery distal part of sixth arch artery is there first as ductus arteriosis and later as a ligamentum arterioism So this anatomical structure never allows this nerve to go above that point and that's why it's a longer recurrent lenial nerve They ask this question in the exam rest everything vanishes Okay So just for the recap guys just for the recap look at this picture and look at this uh this slide also Whatever you find in the slide that I'm showing you a little extra than the PDF that you might be having I will share it with you So just don't worry about it First arch artery maxillary artery kind Second arch artery transate we have this hyoid artery and the stipidal artery that will just embionic arteries only Third arch artery will form common corroted and internal corroted Fourth arch artery on the left side forming the arch of iota right side subclav artery Fifth arch artery degenerate Sixth arch artery is forming what That is forming the pulmonary artery and it is also forming the ductus arteriosis So it's not difficult It's easy peasy lemon squeezy push I'm not I I guess I'm not I'm not saying anything which is uh beyond which is not what is not written in the slide So what are you saying I I hope that when you look at this summary you can make out that what we just saw in the previous picture it is all there on the slide now So I I'm I'm not going to say anything extra beyond the slides but u you know if you find anything that you're not able to understand please let me know Okay Now about the two important anomalies guys Now I just just look at this picture Look at the red color over there The red color here it is first showing the seventh cervical intersegmental artery of the left side which forms subclavven artery And here is a fourth arch artery fourth arch artery and seventh cervical intersegmental artery forming subclavon of the right side The question is if the fourth arch artery of the right side disappears or obliterates if the if developmentally fourth archery of the right side obliterates then what will happen bloody because fourth artery is oblitrated So now what will happen This portion of dorsal iota the cordal part of the right dorsal iota will persist Look at that the cordal part of right dorsota will persist and that will give rise to the aberrant right subclavon artery It's very important to say first that which arch artery obliterates fourth arch artery If the fourth arch artery is obliterated and then there is a persistence of cordal part After that if there is a persistence of cordal part of right dorsal iota that will give rise to the aberant right subclavon artery and this aberant right subclavven artery is going behind the esophagus causing dysphasia lucoria There you can see that that look at the artery over there guys That's the aberant right subclav artery coming from the iota esophagus and it is going behind the esophagus compressing the esophagus and causing dysphasia lysoria Okay What about if the question is now it's very very very close to each other If the question is about that fourth archery is there it is not obliterated Fourth arch artery is there and despite of having the fourth arch artery you still have the persistence of cordal part of right dorsal look at this picture now so you have fourth archery you have a fourth arch artery and now you also have the cordal part of right dorsal iota now what condition will this be now this condition is a double iotic arch so without any obliteration if there is a persistence of cordal part of the right dorsal iota this will give rise to the double iotic arch and the problem with the double iotic arch is This iotic arch is present I'm sorry This iotic arch is present around the trachea and esophagus It compresses the trachan esophagus from like surrounding it here And that is not only causing dysphasia it is causing dysia also It's vascular ring be there's a vascular ring present around the trachea and esophagus that is the yeah that is causing the dysphasia as well as dysnia as well So it's very close They've already asked the question about the aberrant right subclav artery I very strongly feel that double iotic arch could be asked in the exam So it's a very very small thing to remember that for the aberant right subclam artery fourth arch artery is obliterated double iotic arch and nothing is obliterated but still there is a persistence of cordal part of right dorsal iota and that's why we have a double iotic arch okay so this was about the arterial development film sorry now let me tell you a little about the misogast first venus development now when I say misogast this is also a question asked in the recent time guys the key structure here is the stomach Look at the stomach there This green thing that you see in front of stomach that is vententral misogastrium Whatever you see in front of the stomach that is vententral misogastrium Whatever you see behind the stomach or along the greater curvature that is a dorsal misogast Vententral misogast is derived from septum transversum And dorsal misogast is basically coming from lateral plate misolom So just don't worry about that Question what are the derivatives of vententral and dorsal misogast And the easiest thing is think about that liver is developing inside the vententral misogast that's the liver there and spleen is developing in the dorsal misogast and you'll get all the hint because if liver is developing in the ventral misogast guys what is the ligament which connecting the liver what is it the ligament which connects the liver and the anterior abdominal wall that is falselyform ligament the ligament connecting the liver and the stomach is the lesser momentum the ligaments which are surrounding the liver are called as a are called as a coronary ligaments and triangular ligaments So all of them are the derivatives of vententral visas It's pretty simple Think about the ligaments which are surrounding the liver Think about the ligament which is connecting the liver to anterior abdominal walls form ligament And think about the ligament connecting the liver to the stomach that is lesser momentum They're all derivatives of ventral misogast Similarly for dorsal misogast just think about all the ligaments present along the greater curvature Now as you can see the fundus of stomach will be connected to the diaphragm that is via gastroofrenic ligament Then we have a ligament present here connecting the stomach and the spleen that is gastrosplenic ligament Spleen is connected to the posterior abdominal wall where kidney is present Left kidney is present That is a lenorrenal ligament And then obviously it is a greater curvature of stomach So we have what momentum here Greater momentum So I can say gastrophenic gastrosclenic lenorrenal and greater momentum They're all derivatives of dorsal misogyny form ligament is something which is already asked in the exam guys This is already this is a question which is a image based question asked in the exam You can see how many options examiner is still having They can give you an image based question Make sure you point out the structure correctly especially where is vent and where is dorsal misogram and you can easily make out that what are their derivatives Perfect Okay Moving on and one more thing here there is something which is a content of falsifiform ligament only falsely form ligament is like a double fold only guys below in the lower part of falsify form ligament can you see that ligament guys over there that is a ligamentum ties ligamentum ties is a content of fifform ligament it is a content it is present in in between inside the falsify form ligament only and this ligamentum is nothing but the oblitrated left umbilical vein you all know that left umbilical vein is functional before birth but after obviously birth the left umbilical vein only remnant will be there and that is nothing but the ligamentum ties ligamentum ties coming to the venus development from the artiller development let's move on to the venus development now now again for the venus development guys let's first look at these you know the raw material that we have the vein coming from the upper part of the body carrying the blood in the embryo from the upper half of the body is called is anterior cardinal So we have right anterior cardinal vein left anterior cardinal vein right posterior cardinal vein left posterior cardinal vein which are carrying the blood from below And then we have common cardinal vein which they're draining into like look at this Can see anterior cardinal vein coming from above posterior cardinal vein and they're taking the blood into common cardinal vein with the development of kidney Now kidneys they will start developing and can you see the small veins that that you can see coming out of the kidney These are called as a miserric vein guys These veins these small veins over there are called as misonic vein From posterior cardinal vein a vein will come will collect the blood from the kidney and will go and join back the posterior cardinal vein only and that will be called as a subcardinal vein You can see right and the left subcardinal vein Their job is to take the blood from the the developing kidney We call them subcardinal vein Right subcardinal left subcardinal More veins will develop Then we have another vein developing on the posterior abdominal wall and that is called as a supracardinal vein This is subcardinal Now we have a sub superracardial vein We also do have an anesmosis in this region guys that is called as inter subcardinal anesma Look at this animation again That anesmosis or called as called inter subcardinal anesmosis And look at that another vein developing now there again coming from below and joining to the posterior cardinal vein only That is called as a supracardial vein guys This vein is called as a supracardinal vein Supracardial vein Now this is what we have with us guys anterior cardinal common cardinal posterior cardinal subcardinal supracardinal inter subcardinal anesmosis Just just keep this picture in mind And based on that let's talk about the major Venus development here Okay What are you looking at guys Now I've just kind of put those these veins in in the in the background so that we can only highlight the veins which will give us something Now look at the vein which just highlighted to you It's a vein which is carrying the blood from the right side of the head and neck region It basically it's a right brachyphalic vein So I can say that the brachioiphalic vein of the right side is derived from the right anterior cardinal vein It's right anterior cardinal vein Right braklic vein will be formed by the left anterior cardinal vein need to take the blood toward the right side You know superior vennea and inferior vennea are present toward the right side So obviously I need to shift this blood toward the right side and for that I will need an oblique anesmosis So I can say that right brachusphophelic vein is just by the right anterior cardinal vein but left brachioiphopelic vein is by left anterior cardinal vein and this anesthemosis called as a oblique anesmosis is called as an oblique anesmos Please keep reading simultaneously on the side So right brachyophilic vein guys that is only by this right anterior cardinal left brachipalic vein is derived from this entire thing left vein and this oblique anesmosis is also needed here Once the two breaker syphilic vein joins to each other they together give rise to superior vennea There you have it The superior vennea is derived from two sources What are the two sources you're looking at right now on the screen guys One of the sources a small part of the anterior cardinal vein of what side Right side again right anterior cardinal vein and the right common cardinal vein So right anterior and right common cardinal vein together will give rise to the superior vennea Important one Right anterior cardinal right common cardinal superior vennea Chryophilic done Superior vennea is also done here Okay Then inferior venne let's find out the inferior vennea first and then we can we can basically go to the other tributaries of inferior vennea Inferior vennea is derived from look at the highlighter and I want the moment this this animation comes in front of you just start saying those what veins are those guys Look at that posterior cardinal right posterior cardinal vein supracardial vein anesthemosis subcardinal vein and then this subcardinal vein is going to join with something called as a hippatoc cardiac channel also you can kind of ignore it for now hippattocardiac channel basically this here is the posterior cardinal vein of the obviously of the right side then we have supracardial vein this one is supracardinal then there is a formation of anastmosis then this is a right subcardinal vein and then the cranial most part or the terminal part of inferior vennea is by the hippatoc cardiac channel You can ignore the hippatoc cardiac channel whatever is seen in the picture Just compare this with the written part here So right posterior cardinal vein this much there is right posterior cardinal vein over there This is the supracardial vein Then we have what Anastmosis and this is the subcardinal vein of the right It's all right right right Everything is right on this That is inferior vine Inferior ve you got guys look at this highlighter again what are those renal veins right renal vein is just by the right misophricin that's a right misolopric vein forming right renal vein but look at the left renal vein it just left misonic vein is not enough this anastmosis is also required that is called as inter subcardinal anesmosis is also needed here what connects the superior and the inferior vennea and that is another neat image based question imagine it was a neat cateoric image based question that is about the asyus vein guys asygus vein is connecting the superior and the inferior vina now I'll tell you one of the common mistake which people does is that they understand that uh what do you say you know this asygous vein is this well no this is not the zygus vein as vein is partly by this that is a posterior cardinal vein but the main part of the vein is by the supracardial vein this is a right supracardial vein and that's a major part of the of the of the asygus vein So look at the highlight the animation there that red line over there is showing that asygus vein So asygous vein is by the supracardial vein right supra cardinal vein very small contribution by the posterior cardinal vein also So if you have to choose between the post supra cardinal and posterior cardal vein definitely go with the supra cardinal vein as your best answer What else Look at the vein which are going to highlight in front of you guys Gonadal veins gonadal vein you know that right gonadal vein it goes into the IVC whereas the left gonadal vein goes into the renal vein so you can look at the highlighted area it tells you that gonadal veins are derived from what vein subcardial vein but what part of subcardinal vein cordal part of subcardinal vein it's a cordal part of subcardal vein forming gonadal vein whereas the cranial part of subcardinal vein is going to form the adrenal vein look at those vein that's the adrenal vein once again the same story right adrenal vein it drains right adrenal vein drains into IVC left adrenal vein drains into the renal vein here So that is the gonadal vein and gonadal vein is by the cordal part of subcardinal and adrenal vein is by the cranial part of the subcardinal vein These are the major veins that you need to know here So in this picture you can see brachusalic both brachophalic superior vennea inferior vennea asygus vein right and left renal vein adrenal and the gonadal vein and I I very firmly believe that examiner will not go beyond this in the venus development Okay So guys this is about the arterial development and the venus development Now one more thing and then we will conclude on this embryology part that is something which we left in the beginning guys Genital system about the paraxal misorum and lateral plate misum but we did not talk about the intermediate misodum The intermediate misodorm is going to give rise to now this whole thing is intermediate misodum only that you're looking at over there that is all intermediate misum intermediate misodum In the intermediate misodum one this rounded structure that you see is a genital ridge and then the rest is called as a rest is called as a nephroenic cord where we have misonic duct and parameric duct If at all it is an image based question the simple thing is when you find out the genital ridge the duct which is close to the genital ridge is misonic duct because misonic duct is going to give rise to spermatic pathway Obviously spermitic pathway should be close to testice So the duct which is close or more inside is misophrenic duct The more the duct is more outside the more parin position that is parramsonic duct Now guys what about misoperic duct See misopric duct or wolffian duct Now in male or in female the derivatives of miso and parameric duct derivatives of mison parameric duct they they they have some common derivatives like misphric duct whether it's male or female they will get absorbed and will give rise to the trion of the bladder Whether it's a it's a right side or left side the trion of the bladder is by the misonic duct They will give rise to the posterior wall of urethra till the ejaculate duct Posterior wall of urethra very small part of posterior wall of urethra Okay They're going to give rise to the ureic bud and derivatives of ureic bud guys Ure derivatives means like ureic but derivative means the entire collecting portion of kidney Kidney aurora collecting part is is is basically derived from here That is the uh coming from the mison So these are common derivatives misonic duct whether it's male or female these are the common derivatives in from the misophric duct here now there's a point misophric duct is more important in male because it is going to give rise to the spermatic pathway it is going to give rise to spermatic pathway so when I say spermatic pathway think about everything guys ejaculated duct epidmis append appendix of epidmus here vast difference everything the spermatic pathway is entirely derived from the miso In case of female the misolific duct is just having a remnant and that remnant is called as a gartner's duct Gartner's duct guys um the people confuse the gartner's duct with the gartner cyst Please don't do that Gartner's duct is present in broad ligament Gartner cyst is present in the upper part of vaginal wall but gartner's duct duct cyst gartner's duct is present inside the broad ligament here So that's a derivative of miso and parameric duct What about the what about the parameonic that's misopric parameric duct the one which is shown in the blue color there the parramson aopric duct is more important for female because it is going to give rise to most of the female derivatives like it will give rise to the the fallopian tube the uterus and the upper part of vaginal wall also so female derivatives male remnants in male we have appendix of testice and please be careful guys appendix of epidmus is a derivative or remnant of the misolopic duct appendix of testice is a remnant of paramisic duct and there's something called as a prosthetic utricle just don't bother about it prostthetic urethra if you look at the prosthetic urethra on the posterior wall of prosthetic urethra there is a small blind diverticulum present and that blind diverticulum present on the posterior wall of prosthetic urethra it is just a it is just a homologous organ to vagina and female is called as a prosthetic utricle that is remnant of the paramisic duct that is a remnant of parramisophric duct itself here right guys so this is about the embryo biology part here right so I hope it is going good so far just very quickly just let me know if if my speed is fine if I'm able to you know because we have to follow a certain speed in this you know in especially in this one short thing so if I'm going with a better but don't worry about the PDF thing that's my responsibility what even if I'm writing a dot over there I'll give you the same PDF to you so just just no no worries I'm taking lecture from my home actually I have a 7-month old daughter with seven-month old fighter jet of my own Right So if you may hear some background noises so please just forgive me for that Okay Thank you guys I mean okay Wonderful So hisystology guys in between histologology we'll like we'll use it like a salt and pepper in between here because I don't want to bore you with the hisystologology thing histology I'll tell you something interesting thing about hisystologology is in the in the recent time what I've noted is that in fact it's my recommendation to you they can ask you anything but in the recent time what I've noted is that hisystologology questions which they're asking in the exam are very basic they're just asking you identification only identify fibroartage identify kidney identify pancreas so something like that here so most of the slides I'm going to cover in here there was a time 2015 16 17 that they used to ask a very detailed hisystologology questions it's just basic basic identification only they ask you So I would say that if you have read a little less hisystologology or if you're planning to read histologology detail looking it's not that okay these questions was asked in PyQ's 2015 that means they were asking so much of detail no if they want to if they really want to screw us on the histologology part they can still do it no matter how much we read it So I would say this basic identification of the slide is important this what you're looking at right now guys this is a slide of a the cardic muscle right that's is the cardic muscle here cardic muscle how cardicc muscle guys the muscle fibers are first of all profusely branched the branching can be seen next I'll show you skeletal muscle skeletal muscles are unbranched they're parallel bundles but they're not branch but you can clearly see branching over there and that's why it's a cardiac muscle what about nuclei the nuclei are oval and central in position can you see the nucle nuclear are oval and central They're centrally located They're not on the periphery and they're they're oval They're like they're not like flat nucleus They're oval nucleus there The most important thing in the cardiac muscle is like if if if I just may look at these three circle which I've just shown you guys Look at over there This one this one and this one Can you see that line over there That is nothing but the intercalated disc And they've asked this question earlier also Intercalated disc is basically a a functional syncium is present there What type of junctional complexes are present in the intercolated disc We do have zona adherance We do have gap junction and we do have a desmosone These are three main you know junctional complexes which are present over there Out of which out of which gap junction is the one which allows the movement of action potential from one cell to another and that's why it is it is the reason that it becomes a functional sync guys Obviously when you give a when the stimulus goes into the cardiac muscle it can travel from one one muscle to another one fiber to another that is because of this gap junction Desmosomes desmosomes are the one which are anchoring structures These are anchoring filaments which are holding these muscle fiber to each other here So the question here is that what type of junctional complexes are present in between the in the intercolated disc So we have this adherent junction we can call it zona adherence gap junction and desmosome and desmosome are present there right and gap junction is the one because of which this intercalated disc is called as a functional singium it's a functional singium okay moit my dear I cannot increase the audio because my mic audio is full already and I think if I go beyond this point it just will start making some you Maybe the audio issues on your side because it's if if other people were having this audio issue they they certainly would have told me Okay Now look at this picture guys This is a slide of a skeletal muscle First of all why it is a skeletal muscle Can you see the branch These these these fibers are not branched They're parallel bundle unbranched They're like individual bundles are there Secondly look at the nuclei How the nuclei they're flat and they're peripheral We have a flat and peripheral nuclei present over there multiple nuclear flat and peripheral nuclear present there and there's striations present inside them Now these triations the cross triations is a is a very important feature of that In fact they have asked this question on the cross triations of the skeletal muscle It's more of a physiology question actually but they've asked this question on the cross triations like image like this here I'm I'm very sure that you read about this image in your in your physiology class in much detail Now I I I hope you know that this these lines over there are called as a these are the called as Z lines and from one Z line to another Z line that is one sarcomia you're looking at here like functional unit of the cell that is sarcomir that is between the two Z line here what is this band over there this this this central line over there is M line or M band M line and this area is A band the anisotropic band or A band and what is a band basically a band is nothing but it's a length of the the meiosin filament the meioin filament is the A I band is the unover overlapp unover part the the portion of the the actin filament which is not overlap by the min filament that is called as a the eye band an unover overlapped part of the the meiosin filament is called as what it is called as a h zone the question here is z line m line A band change they are like the way they are they will be like this only here What will change in length during the contraction that is I band and H zone Obviously when the muscle contraction will take place this overlapping will be there more So A band will get shortened and H zone will also get shortened because in the contraction these bands will get shortened here So the the length of which of these bands and lines will get altered So it is I band and H zone which would get altered during the contraction If I if I remember correctly physiology this was the question asked So that's a fun picture of a skeletal muscle right Okay Okay Moving on guys Let's now move on to our next topic after after embryology That was a major part of the embryology that we discussed here And again whatever you've read everything is important in the class in the in the regular class lecture or anywhere you attended the class This these are the topics that you have to focus on like right now if you look at myself and um how many days I'm just if in supposed to happen on the date given so this is something that you to read This is something you just cannot leave them and in the four five hours of an actual discussion my recommendation goes with these topics here So look guys let's get started Now in the upper limb first I'm going to start with few muscles because these are the muscles which again are asked in the recent time Look at the muscle which are stretching from the vertebral column to the scapula and then we have muscle from scapula to humorus also I hope you can appreciate the muscle coming from the upper part of cervical vertebrae from the transverse process to the the medial border of the scapula that is leviator scapula and the two muscle which are also coming from the the from the from the this upper thoracic vertebrae that is the the roboid minor and romboid major Roboid major was one of the question asked in the recent time Levi scapula guys the name says levitus scapula is a muscle which is responsible for elevating of scapula and romboidius minor and major they retract the scapula they not only retract the scapula they slightly elevate the scapula also because look at the muscle fibers are obliquely present so they retract and elevate retract and elevate romboid minor and roboid major first of all these muscles are supplied by dorsal scapular now dorsal scapular nerve will be running like this it is running like this in this region and this dorsal scapular nerve which is coming from the roots of the brachial plexus It is going to supply all the three muscle here roboid minor and roboid major muscle guys these two roboid they retract the scapula I told you and they also elevate the scapula and they rotate the glenoid cavity downward and that was a question asked in the exam that what is the effect of the romboid major muscle on the glenoid cavity imagine if this is a glenoid cavity let's say this if this my wallet here is a glenoid cavity and here is is is the scapula I'm sorry and if this is the the glenoid cavity here facing toward the lateral Right So when the scapula is retracted above and medially my scapula will rotate like this That mean that my glenoid fossa the glenoid fossa is going to turn downward Every time you elevate the scapula medial border and and retract it your glenoid fossa will turn downward Rotation of the glenoid fossa upward is done by the serrus anterior muscle That is for the overhead abduction Rotating the glenoid fossa downward is done by the roboid minor and roboid major muscle which are retracting the scapula That was one of the question asked Okay Okay Now hubal fracture and nerve injuries guys Now this is again a question I have to focus on the on the areas from their questions being asked here because these topics guys I mean the people who attended the class with me they know that we discuss these topics for the six long days from morning to evening and now we are just doing it all in 4 hour 5 hours of time So obviously we have to kind of only focus on the important part here guys hummeral fractures and nerve injuries Now what are the major site of hummeral fractures and what nerve will get involved in this If there is a fracture at the surgical leg of the humorus surgical leg of the humorous involvement what nerve will get Axel nerve will get affected here We know axel nerve winds behind the surgical neck of the humorus and that's why it is affected in the the the surgical neck of the humorous fracture Mid shaft fracture which nerve radial nerve because spiral groove is giving passage to the radial nerve So mid shaft fracture most commonly nerve involved is the radial nerve SN midshaft fracture rad is the only nerve in getting involved You can have involvement of median nerve also muscular vitinous nerve also but usually it's the radial nerve because it's closest to the bone in the spiral groove Then supraondela fracture The nerve which is most commonly affected in the supraond fracture is the nerve which is not even present over there I mean it is going to separate in the forearm only and that is anterior interrochious nerve I'm sure this question is asked in the ortho as well earlier So it's medial nerve but more precisely it's the anterior interrocious nerve which is involved in the supraond fracture medial epicondile fracture it's the it's the all nerve guys all nerve involvement in the medial epicondile fracture and even if it is a lateral epicondila fracture the most commonly involved nerve is still nerve because of what tardy alner of palsy it's a it's you know the tardy nerve of paly guys what is going to happen there is a there is a cubitus deformity if there's a fracture of the lateral epicondile this angle will increase and if the angle will increase like increase from the medial side if this angle will increase between the humorus and and the forearm bones then there's a stretch on the medial side and that again causes the alno palcy So tardy unlopy be it medial epicondola or lateral epicondular fracture the most commonly affected nerve is nerve in both cases Okay Okay Moving on now in the muscles of the upper limb you cannot ignore the hand guys I mean with the again the people who attended the class with me you know that how much of detail of hand we've discussed about the spaces and the muscles and you know different nerves and everything about hand is important to you Now first thing when you look at the picture here a question obviously they can cut down few muscle and they can show it to you like I I I again very firmly believe that if they want to give you a image to identify the muscles in hand they most probably if they're asking the thinar hypothal lumbrical muscle they will give you image like this If they want to ask you intro that's a different story but if they want to ask you thinar hypothal lumbricals this will be the picture This kind this will be the kind of image that you'll get So first understand if you see a muscle present in the thinner region more on the outer aspect here that is abductor and if the muscle is more on the inner aspect that is a flexor abductor policis bravis flexor polis because we have the longest in the forearm also so it's a abductor policis bravis and flexor policis bravis opponent's policance policis is a muscle which is attached to first metacarpal it is placed very deeply inside so we will not be able to see The opponent's policis muscle opponent's policy it will be like present deep to these two muscle in somewhere in between the two So I cannot see opponent's policus in this image The another muscle the the main muscle that they will ask you on this or they usually ask us is the adductor policus a big triangular muscle and to see the entire addolis muscle I need to remove these tendons Once I remove these tendons then I will be able to see the erector polollus muscle more And you see this big muscle which is coming from the mainly from the shaft of the third metacarpal there Look at this big triangular muscle that is ereatropololis A muscle a very important muscle for the gripping because the one which brings the thumb inside and this aretropolysis is the muscle which is supplied by you can go with the color code guys Red is for the nerve and blue is for the median nerve So this is one thinar muscle which is supplied by the al nerve and that's why uh the test which is done for it book test guys you ask someone to hold any object between the between the between the index finger and the thumb So obviously you'll be holding it like this Let's for example if I once again take this wallet here If I if a person is pulling this wallet from on the other side my erector pololis is strong enough not to allow this wallet to to to leave the hand But if my retropololis is not working what will I do I will do a trick movement I will curl the thumb like this to hold this wallet in my hand And that is done by the other muscle called as a flexor policus longus muscle And this sign when you curl your thumb to hold the object is called as a from sign Yeah that is the thumb the bending of the thumb will be seen there and the test is called as a from sign Unlearn of I'm sure you all know about this test called as a from sign Yeah Okay On the other hand same story guys If the muscle is more outside that is abductor If the muscle is more inside it is a flexor Abductor flex opponent again because opponent is deeply placed muscle right So out of the thinar and hypothar muscle these are the five muscles you are like usually you can get as a question but nothing can beat adductor policy that's the most important muscle to be identified in the cateoric image based question okay moving on now what about the lumbricals same picture guys it's the same image that you saw last lumbricals now sometime people say we are confused between the lumbricals and introy I'm like no there is no confusion between lumbricals and introy if you're looking at lumbricals you must be looking at tendons Can you see tendons over there Look at the tendons Tendons Tendons Tendons Tendons are visible So the muscle which are taking that origin from tendon are lumbricals Interroshi are taking origin from bone So how will you see tendon over there The tendon of flexor digital profundus FDP tendon Flexor digital profundus tendon is giving origin of the lumbrical muscle and L for lumbrical and L for lateral Every lumbrical is going from the lateral side of the corresponding finger Guys look at this First lumbrical second lumbrical third lumbrical fourth lumbrical they will reach the finger They'll reach their corresponding finger from their lateral side L for lumbrical L for lateral side Lateral sides right That's the four lumbrical we have Out of which first and second lumbrical which are actually uniinate also maybe in the kadaic image you will not be able to appreciate uni bipinate but the first and second lumbricals are uniinate and they are supplied by the median nerve Third and fourth lumbrical are bipinate As I said you may not be able to appreciate the pination in the cateoric image but third and fourth lumbricals are bip pinate and they are supplied by the alnner nerve So two lumbricals are by the median nerve of the lateral two which for the index finger and the middle finger lumbric that is the median nerve and for the ring finger and little finger these lumbricals are supplied by the by the nerve that's the lumbricals there okay okay I don't think that it is stuck at all from from my end because you know my internet speed is almost one almost 1,000 Mbps right now So there's no chance that it is stuck from my side Okay Coming to the intro guys palmer introy and dorsal intro Now what you see in the palmer and dorsal intro or we all know this pneumonic of pad and dab Now palmer intro pad that is palmer intro for adduction and dorsal intro is for abduction First take the principal digit guys Principal digit is a middle finger here The middle finger coming close to middle finger is adduction and going away is abduction So palmer in is doing this adduction So that means all the fingers will be having pal intro except middle finger Middle finger moving in the adduction of the fingers the other fingers need to come toward the middle So palmer intro is absent on the middle finger That is one point they ask you Uni they are all uni in nature and middle finger is divided of there is no palmer in the middle finger And the test which is done to check the integrity of palmer introy that is called as what test That is called as a card test guys That is called as a card test right intro This pin in it may be present or may not be present We already have a muscle called as adductor policis We have such a such a main adductor of thumb is already present We discussed that earlier So thumb palmer intro it may be absent usually but thumb palmer intro the first pushia it could be absent as well No surprises there Dorsal intro again foreign number all dorsal intro are bipinate and the job of dorsal intro is abduction Now the point is guy we already have the strong abductors for thumb and little finger that's why there is no dorsal intro for thumb and there's no dorsal intro for little finger but the middle finger which was not having the palmer intro look at that middle finger is not having palmer introy is having double dorsal intro s middle finger move middle finger movement whether it is toward the lateral side or middle side it is done by the dorsal introy only So no palmer intro on the middle finger but dorsal intro We have second and third dorsal intro present on the the middle finger And the test which is done to check the integrity of the dorsal intro it is called as a egawa test guys The test is called as gava test You can see how it is done A patient is asked to place the hand on the plain surface and ask ask him to move the middle finger because middle finger the movement is not done by pal in There is no pal in middle finger So if you're moving the middle finger whether it is toward the lateral side or middle side it is done by dorsal intro only that's why the ego test is specifically for the dorsal intro here car test for the pal inro and eava test is for the dorsal yeah correct absolutely perfect cleaval fasia guys another question another topic from where the question asked in the previous exam cleaval fasia a fasia which is extending from clavicle to the pectoral muscle now the fasia which is going to enclose two muscle One is subclavius muscle A very small muscle which is present somewhere here in the in that region just below the clavicle and the other muscle is here that is the pectoralis minor that is called as a cleav pectoral fasia This muscle subclavius there look at the pointer guys and this muscle coming from third fourth and fifth rib is the pectoralis minor muscle In the recent time last year in fact again there was a question asked they showed the nerve piercing the pectoralis minor muscle and coming out and that nerve was a medial pectoral nerve But tell you why people got it wrong The people got it wrong because when they saw the nerve piercing the petrol minor muscle and coming out they compared this nerve with the nerve above The nerve that you see guys above here this nerve here that nerve right now this nerve look medial and that looks like more lateral That's why they got it wrong Medial pectoral nerve and lateral pectoral nerve is not about which one is lateral which is medial It is about which cord of brachial plexus are coming from Lateral pectoral nerve is coming from lateral cordobraal plexus Medal pectoral nerve is coming from medal cordobraal plexus So keep it simple If you see a nerve piercing the pectoralis minor muscle minor pierce piercing petrolis minor then it is what now It's a medial pectoral nerve It's a medial pectoral nerve But if you see the nerve piercing the fasia present above the pectoralis minor The cleavctoral fasia is pierced by four structures Lateral pectoral nerve is one of them So we have one vein one artery one nerve one lymphatic Syphilic is the vein which is piercing clipal fasia that is syphalic vein Lateral pctoral you can see the nerve over the lateral pctoral We have a thoracic trunk or thoracic artery This vein is syphalic vein and we do also have some lymphatics as well guys There are some lymphatics which are draining into the epical lymph node They're also going to pierce the cleavetrolia That that also is a question asked in the exam here that what structures are pierced in the cleaval fasia One vein one artery one nerve one lymphatic syphalic vein thoracic artery lateral pectoral nerve lateral pectoral nerve And then we have lymphatics which are also piercing it Okay What is the extension of the cleavage pectoral fasia After covering the pectoralism muscle the extension of the cleave fasia below is called as suspensory ligament of axilla Guys look at that That region over there This area here is a suspensor ligament of axilla That is the one which is basically keeping this floor of the exilla slightly elevated slightly dome-shaped Your floor of the exel is not flat It is slightly dome-shaped and that is because of a suspensary ligament of axilla Okay Now transverse section of axel talking about this region only Now if you take a transverse section of axilla how this section is going to look like The transverse the TS of the axilla is going to look like something like this Here this is again a question asked in the exam When you take a TS TS of the axilla laterally you will see humorous bone So that that's the humorous bone over there You can see medally I will see rib cage that is a rib cage that you're looking at here Anteally I have pectoral muscle that pectoralis major and minor is there Look at the two muscle over there that is pectoralis major and minor that is anterior Major minor is the muscle which is going to cover the scapula that is subscapularis and the muscle which is going to cover the rib cage is serus antior So that muscle is subscapularis It is in front of the scapula and the muscle which is covering the rib cage is serus antior And guys this is serus anterior Then the nerve which is supplying serus antior is the long thoracic nerve also Longac what is there inside Now inside the axilla I can see that is axillary sheath that that white color the sleeve like structure that you see that is axillary sheath Axillary sheath can you see axillary artery there Ailary vessels are there and around the axillary artery I have chords of brachal plexus Now obviously this is toward the lateral side That's a lateral cord of brachal plexus That's a medial cord of brachal plexus That's a posterior cord of brachal plexus Posterior cord of brachal plexus gives origin to many nerves One of them is a subscapular nerve Upper subscapular and lower subscapular nerve And they are going to supply the subscapularis muscle guy There is subscapular nerve is there Upper subscapular lower subscap upper and lower but subscapular nerve here And then we have the lateral cord and the medal cord of the brachial plexus to be seen If I remember correctly in the INICT back when it was as they asked this question on the transverse section of axilla and they asked three structure in this I'll tell you what three structures were there they asked the medial cord of brachial plexus they asked the long thorosic nerve and the subscapularis these were three structures specifically marked in that picture and they asked identify them here one was the medial cord of brachal plexus long thorosum and subscapularis muscle I remember that correctly Okay Coming to the brachal plexus Now again whatever we read in brachal plexus about branches and everything that is fine but from the core purely from the exam point of view what is important from the imagebased point of view guys Brachal plexus is formed by the vententral primary of C5 to T1 You know C5 C6 C7 C and T1 Once the C5 and C6 roots will join C7 is there C8 T1 will join They will form the roots will join to form what Trunks So we have upper trunk middle trunk and lower trunk After the trunk these you can see these trunks are giving contribution to each other As you can see the upper trunk is giving a contribution to the middle Middle is giving a contribution to lower is giving contribution middle and middle is giving contribution back to the upper This area of the brachal plexus called as a division of the brachial plexus and division is one part of the brachal plexus branches There are no nerves coming out from there and that also is one of the INICT question that which portion of brachal plexus does not give any branches like there are nerves coming out from the roots from the trunk from the chords but not from the division There are no branches from the division part here And then finally we have the chords of brachal plexus As we just discussed the chords of brachal plexus are named based on the relation to auxilary artery lateral to auxiliary artery We have lateral cord posterior to auxilary artery posterior cord medial to auxiliary artery medal chord Now I can assure you that in the exam guys they're not going to ask you every single branch from the cord of brachial plexus It's not an easy thing because every brachial plexus might look a little different They may not ask you the branches coming from bra chords or brachial plexus But they can ask you the continuation of the chord like lateral cord continuation Lateral cord continuation guys this is a continuation lateral chord That's a continuation of posterior chord That's a continuation of the medial cord Here the continuation of the lateral cord is in the form of muscular cutaneous nerve The continuation of the posterior cord is in the form of radial nerve And the continuation of the medial cord is in the form of the nerve The long nerves which are going into the upper limb So muscularis lateral cord continuation Radial nerve is a continuation of the posterior cord And nerve is a continuation of medial cord or brachial plexus And median nerve is something which is coming from both lateral as well as medial cord of brachial plexus That's the medial nerve Medial nerve is one major nerve of the upper limb cord It is coming from lateral cord also and it is coming from medial cord of the brachial plexus Okay So at least make sure that you identify these these continuation of the chords of the brachal plexes there Now in the brachal plexus the two major injuries guys I'm sure you read about these injuries in the in the ortho as well that is the injury to the lower trunk of the brachal plexus that is called as a clumase paly and the injury to the upper trunk of the brachal plex that is called as a herbs palsy Now first let's talk the clump case pel if the injury to the lower trunk is there to the clump case paly that means the root value which are affected are which one that is C8 and T1 lower trunk C8 and T1 C8 and T1 C8 and T1 injury it is going to affect those nerves which are supplying the intrinsic muscles of hand If the C8 and T1 is injured guy that means your intrinsic muscle of hand will get affected and involvement of all the intrinsic muscle lumbricles and introsion will get affected the person will get a claw hand There's a hyperextension at the MCP joint and flexion at the interferingial joint There will be claw hand in case of the clump case valy and it's a complete claw hand claw hand claw hand will be there but because the injuries to the T1 also it's a C8 and T1 injury to T1 can also cause Hner syndrome also So the patient with clump case felcy they may have horner syndrome also but horner syndrome be similarly if the injuries to the upper trunk of the brachial plexus the injury to the upper trunk of brachial plexus is called as herbs felcy in herbs felcy the root value which are affected is the C5 and C6 C5 and C6 is a root value in many nerves but if I talk about some particular muscles which are supplied by C5 and C6 via rad via via axillary nerve and muscularinous nerve so it is deltoid and it's the biceps and brachialis muscle Corcoalis baja guys correal is supplied by C7 So corcoalis is spared mainly the deltoid muscle and bicep muscle is affected mainly or muscle but just think about to muscle only If deltoid is not working you are not able to abduct So shoulder is adducted So we have a adducted shoulder Bicep is not working so elbow is extended and it is also pronated because bicep is a very strong superenator also So we have a extended elbow and the pronated forearm as well Adapted shoulder extended elbow pronated forearm I'm sure we are talking about what policeman's tip hand or the policeman's tip deformity and the policeman's tip deformity is feature of the herbs here So generally in as in questions they will ask you about clump case spying which root values are affected which trunk of brachial plex is affected here Similarly pel which root value will spared like which root value is spared the C7 root value is spared and C7 supplies which muscle that is correalis muscle that's why out of the three muscles present in the anterior compartment of the arm biceps and brachalis are affected but correal baja corcois is spared because c7 is supplying the correlis muscle Okay ch sir moving on going to the the three major nerve end injuries talking about the upper limb how can we leave on the nerve injuries guys nerve injuries is the most important thing in in the upper limb here now radial nerve which we just saw it is coming from posterior cord of brachial plexus coming from C5 C6 C7 C8 and T1 what's the course of radial nerve radial nerve starting from exilla it goes behind the humorus into the spiral groove as you can see comes in front of the lateral epicondile and divides in front of the lateral epicondile into a superficial branch and the posterior interrochious nerve into the posterior interrochious nerve that's the radial nerve course I take now in the axilla the radial nerve supplies the tricep muscle that's one thing it again supplies triceps muscle into the spiral groove or the the radial groove then it supplies another important muscle called as ECRL extensor karpy radialis longus and what makes ECRL so important muscle it is one of the wrist extensor That's why it is important It's one of the wrist extensor It is supplied above the lateral epicondile only that is wrist extensor ECRL And then we have posterior interroesious nerve which is supplying remaining all extensors Remaining extensors they are all supplied by the posterior interro when I say extensor digtorum extensor you know carpnaris extensor digit minimize extensor indices extensors all other extensors are supplied by posttos Just one ECRL extensor carpet is longer supplied by the radial above the lateral epicondile Rest are by the poster intentious nerve The superficial branch is a cutaneous nerve It just supplies the skin on the dorsom of hand lateral three and a half What about the radial injuries Radial nerve can get get injured in the axilla I'm sure you all know that that is called as a crutch paly Radial nerve get injured into the spiral groove that is a Saturday night paly radial nerve can get injured in front of the lateral epicondile and there could be direct injury to posterior interocousious nerve also very close to the head of the radius So that is posterior intro injury can also be there The fourth common feature guys if the radial nerve is injured in the axilla here right here all the extensors are gone Tricep is not working Wrist extens not working So the position of the patient will be flexed elbow wrist is dropped Fingers are also dropped and sensory loss is there So in the in the crutch paly elbow be flexed wrist be flex finger be flex or sensory loss be all the joints are flexed so we have flexed elbow wrist drop finger drop sensory loss if the injury is in the spiral groove the second one guys in the spiral groove that is a you know all the Saturday night paly it is Saturday night here in the Calgary today uh tonight it's I mean the Saturday night right now after Sunday morning so this is in the Saturday night paly in Saturday night paly guys what happens is That tricep is partly spared I be tricep is partly working So patient is having difficulty in elbow extension Difficulty difficulty in elbow extension and rest everything is same Wrist drop finger drop everything is same Only thing is in this case it was a flexed elbow Here we have weakness in elbow extension If the injury is in front of lateral epicondile the first of all tricep is working perfectly all right No problem Another important thing ECLB If ECRL is spared the patient will not have wrist drop because ECRL is a what Wrist extensor That's why there is no wrist drop Finger drop will be there Finger drop will be there Sensory loss will be there but wrist drop will not be there because ECRL is spared at the lateral epicondile case ECRL is spared And if the injury is to the posterior intros directly again we have what We have a finger drop but this time there is no sensor loss because which no is also spared Superficial branch is also spared So patient is only having a finger drop in that case So based on the symptoms of the patient you can make out that possibly the location of the injury Flexed elbow wrist drop finger drop sensory loss exelomega Saturday night palsy weakness of elbow extension wrist drop finger drop sensory loss Lateral epicondular injury where is only finger drop and sensory loss Posterior intros injury there is only finger drop There is no sensory loss in that case Right So that is about the the radum injury What about median nerve Now median nerve and nerve one good thing is that these nerves are not supplying anything in the axilla or arm The first muscle supplied by median nerve is after the elbow So guys look at the median nerve over there That's a med which is going into the cubital fossa and from the cubital fora it runs between the forearm muscles and then passes deep to the flexor retinol That green band over there is a flexor retinolum Let me start with the terminal part Once the median reaches the hand it is going to supply the thinner muscles Remember all thin muscles except adderpololis Adder polysicus was supplied by the alernum So all thinar muscles except adector polysus and it also supplies the first two lumbricals Unipinate lumbricals L1 and L2 The uniate lumbricals are also supplied by this just before just before the medial Now that let me zoom in for you Just before the nerve goes deep to the flexor retinolum it gives off a branch which is passing superficial to flexor retinolum and that is called as a palmer cutinous branch Guys palmer cutinous branch is the one which is going to supply the skin of the palm of the palm not the fingers palm king supply and why it is important because if the patient comes to you with a carponal syndrome then thinars will be gone lumbric will be gone but this nerve will be working because the nerve is above the flexor retinolum and that's why in carpal tunnel syndrome the patients they do not have sensory loss on the hand on the palm they only have sensory loss on the fingers palm any fingers sensory loss in carpal syndrome we'll see that in the forearm medial nerve it gives off branch called as anterior introious nerve It's a deep nerve called as anterior intro nerve Main medial nerve supplies the superficial flexes like flexor digtorum superficialis flexor carpidis other muscle FDS is important Remember that flexor digtorum superficialis anterior interroious nerve which is a deep nerve It supplies the deeper muscles like flexor digum profundus lateral half lateral half of flexor digundus and flexor policus longus And what makes these two muscle important was flexor digundus muscle it reaches the distal falx flexor policus longus also reaches the distal falx they are the only muscle on the flexor side distal fings that is flexor digital profundus and flexor policus longus they're reaching the distal ph distal fings flex if you want to flex the distal fings I need this nerve I need this antroous nerve otherwise you cannot flex the distal fings Medina nerve injury higher injury at the elbow or above the elbow Lower injury at the wrist wherever like close to carpal carpal syndrome or there could be a isolated injury to the anterior intros guys Anterior introious nerve injury also anterior introious nerve injury If it is a higher injury or lower injury let's go with these two guys If there's a higher injury or lower injury of the of the median nerve they ape thumb deformity because thinners will get affected the patient definitely will have a thumb deformity but if a patient is having a higher injury that means his fds and the lateral half of FDP is also not working and that's why he's not able to flex the index finger especially but in most of the cases middle finger flex so when you ask the patient to make a fist e thumb deformity is there when you ask the patient to make a fist so he will have a pointing index finger or maybe hand of benediction like this that is while making a fist So eighth deformity is there for sure but hand of benediction or pointing index finger will be there while making fist that is important patient normal while making fist fist b you will see the pointing index finger or hand of benediction that is because of higher injury because FDS is not working lateral half of FDP is also not working If it is a lower injury then obviously FDS is working FDP is working So in this case you will have a thumb deformity no problem in making the fist Patient can make a fist but I told you if the injury is at this point which now will be spared the palmer cutinous branch will be spared And if palmer cutinous branch is spared that means the sensory loss will be seen only on fingers but not in the palm A thumb deformity but there is no sensory loss on the palm That is the case of lower injury or the carpal tunnel syndrome If there is a injury to anterior intros just imagine the main media nerve is working Medial say media nerve is working fine But the anterior intro nerve is affected Guys if antroas nerve is affected that means you're not able to flex the distal fings of this index finger You're not able to flex the distal fings of the thumb And that's why you're not able to make a okay sign like this You cannot make a circular okay sign like this You'll make a flat okay like something like this Look at this on this on this one side You can make a circular okay That is a normal okay because the distal filings can flex But in this case the distal fings are not able to flex That's why the patient will make an okay sign like a flat okay sign here which is an indication of anterior introious nerve injury here So it's a higher injury lower injury And then we have if there is injury to only anterior introious nerve then you see a patient who's having the positive okay sign anterior intrusion of supplies FDA and FPL sir Yes it does It does FDP lateral half FPL even pronator quadrus also not very important so I did not mention here coming to the nerve guys the last one all nerve as we know the root value for the nerve is C7 C8 and T1 heavily C8 and T1 because we need to supply the muscles of handler nerve it passes behind the medal epicondile where it is very vulnerable to injury also nerve is basically passing through a canal which is present here or that is a that is called as a cubital tunnel it is made up Flexor carpeyaris muscle close to the elbow there is sorry yeah look at that that's a flexor carpelaris muscle and flexor cararpis muscle gives a passage to this nerve that is called as a cubital tunnel so nerve can also get injured in the cubital tunnel called as a cubital tunnel syndrome then this nerve in the forearm what you'll see it is going to supply it is also going through a canal which is like from called as a grenal present deep to the pisohe ligament so if it is a higher injury of the alna nerve generally it is could be because because of medial epicondile fracture It could be because of the cubital tunnel syndrome or if it is a lower injury of the all nerve that is gy canal syndrome nerve can get compressed to the gy canal nerve in the forearm it is just supplying one and a half muscle one and a half guys when I say one and a half one is what one is this only now one is a flexor carpalis only and half of which one flexor digital profundus medial half of flexor digital profundus when the nerve passes through gy canal then the majority of the intrinsic muscle of hand are the alo like first of all it supplies all hypoththenas after that it supplies is all introi it supplies lumbricals also binate lumbrical which one third and fourth lumbrical also and it is finally going to supply the erector policus muscle as well the ereysis last muscle to be supplied by alner nerve it is also called as a graveyard of all nerve this this erectorus muscle is also called as a graveyard of nerve okay now whether it is the nerve injury in the higher level or the lower level yeah claw hand to obviously intrinsic muscles are involved so there will be claw hand the only thing is if it is a lower injury if the patient is having a lower injury the claw hand will be more prominent if it is a higher injury the claw hand will be less prominent and I'm sure you all know that is called as paradox and this ner paradox ult paradox is because of which muscle that is because of flexary digital profundus in the lower injury if the if the patient is having a unum injury in the lower part and imagine fdp is working that FDP muscle will cause more flexion at this distal interfallenial joint and that's why it looks like a more severe claw hand here So lower injury is not a severe client Higher injury may we have a less severe client and that is called as a narr paradox That is the paradoxical situation called as paradox Yes Perfect Yes guys FDP is by two nerves here Neil FDP is is a hybrid muscle It is supplied by two nerve So few more questions on hisystologology guys When I talk about hisystology well nothing is more important histologology than the slides of some lymphoids So you're looking at some lymphoid slide What you're looking at right now guys this is a slide of a lymph node lymph node slide and if it is lymph node how we going to separate the lymph node from pelatin tonsil from spleen and from thymus in first of all in the lymph node you can see there is a capsule over there like on the top that is a capsule there that's that's a capsule region and you can you can divide the slide of lymph node into the cortex and medular part The cortex and medular can be seen separate these lymphatic nodules I'm sure you can clearly make out the lymphatic nodule with germanal center These lymphatic nodules and lymph nodes are present only in the cortex media only in the cortex we have lymphatic nodule number one Number two capsule and tbvic You have a capsule and tra there is capsule over there and these the tbvicular there These these extensions are called as a tbucle and we have a space present deep to them That space is called a sinus Either you call it subcapsular sinus or that is called a subtraular sinus lymph lymph node The lymph basically goes into this region here That sinus is called as a subcapsular or subtraular sinus which is a which is a which is a very you know unique feature of the lymph node You will not see the sinus like this in the spleen or in palatin tonsil So subcapsular or subtribicular sinus will be there Tribular tribular present there As I said lymphatic nodules are present only in the cortex Medela we have the chords medularary cords are there and sinuses and at the junction of the cortex medula this is a area which is called as a paracortex and paracortex is called as a thymus dependent zone lymphatic nodule guys in the lymphatic nodule we have mainly what belymphosytes and this is the paracortex region where we have tly lymphocytes here that's a question asked pura question but the question was asked that which part of the lymph node is thymus dependent portion of the lymph node thymus dependent portion Tlymphosytes and Tlymphosytes are present where at the junction of the cortex and medulla that is a paricortex that is where we have the Tlymphosy So that is a slide of a lymph nodium Okay Okay Now if you look at this slide again I can see lymphatic nodule Again I can see lymphatic nodule uh I can I can actually talk about these injuries and all that but I I'm trying to respect that whatever is done ortho if these things are done why we want to do that the same thing from the two different sources right that's that's why I have to refrain myself from discussing everything limited time can we have to discuss most of the topics so obviously we have to I have to kind of cut down onto the information which are not very important or either covered in other subjects here so so guys once again look at the lymphatic nodules you can see lymphatic nodules This time apart from lymphatic nodule you can see a big space over there present over that's a palatin tonsil that's that lymphatic nodule that the space over there is a tonsular crypt tonsular crypt and tonsular cleft you know that when you look at the p the oral surface of pelatin tonsil the spaces that we have in between them that is called as a tonsular crypt over there right the most important thing about the pelatin tonsil would be that the oral surface of the pelatin tonsil especially crypt present that is covered with the stratified squamus Epithelium lymphatic nodule and you are looking at the stratified squamus epithelium and some crypts are visible to you It is going to be pelletine tonsil Simple Look at the next one In this slide what slide this see again I can see lymphatic nodule Half lymphatic nodule half lymphatic nodule There is lymphatic nodule present everywhere Right Lymphatic nodules is there I cannot see any crypt over there I cannot see any stratified squus epithelium And because lymphatic nodules are dispersed everywhere This is a slide of a spleen or spleen speciality guys there is no differential cortex There is no cortex medula You can see lymphatic nodule and each beach lymphatic nodules are spreading everywhere That's why there is no differential cortex and medulla It is a slide of a spleen If I zoom in on one like more into this lymphatic nodule area where lymphatic nodules are present The important feature of the spleen is that first of all this lymphatic nodule area this is called as the in the spleen that is called as the white pulp White pulp WBC's white blood cells over there that's why we have white pulp is there we have lymphocytes present in that region that is white pulp then we have a blood spllayed into the paranka that's why it gives a red tinge color over there that is that is called as a red pulp over there because RBC is present important thing spleen slide in the slide of a spleen you're going to identify that the lymphatic nodules are having blood vessels can you see arteries over there look at these arteries look at these arteries look at these arteries blood vessels blood vessels inside the lymphatic nodule Guys blood vessels present inside eccentrically placed blood vessels inside the lymphatic nodule is the feature of the spleen Simple as sir If you're looking at a lymphatic nodule covered with a capsule there is a subcapsular and subtraular sinus and the lymphatic nodules are present only in the cortex lymph node If you look at the lymphatic nodules which are lined by the stratified squamus epithelium and there is a crypt also visible to you Crypto now stratified epithelium is there It is a slide of a spleen It is slide of a pellet and tonsil If you're looking at a slide where the lymphatic nodules are dispersed everywhere because there is no differentiated cortex and medulla and there's a artery to be seen inside the lymphatic nodule It is a slide of a spleen Just work for the basics to identify the structures So that is a spleen over there Yeah Non-caratinized Yes of course Orality non-caratinized Now again you're looking at the lymphatic lymphatic lymphat lymphocytes are seen but there is no lymphatic nodule here it's a slide of a thymus Now in the slide of a thymus what you going to see that entire thymus is divided into by by the septum Can you see all the sept over there Look at the septum Look at the septum Look at the septum They're dividing the entire thymus into small small lobules and every lobule is having its cortex and medula The cortex beha but like there is no lymphatic nodule there We do have a lymphocytes Now you can see cortex over there and you can see medulla also But one thing is to be noted these tbuclea are sending extensions inside Can look at this I'm just making a red color over there Look at these extensions And because of these extensions your cortex is also divided inside one lymphatic inside one lobule the tugular are going inside and these tugles are dividing the cortex but they're not reaching the medulla So it's like all these cortex is sharing one common medula inside Generally you can identify thymus like this also if they let's say they give you a very good picture of of of an old thymus and let that too little zoomed in maybe at 40x or beyond 40x into the middle part you may also able to appreciate something that is called as a hassel corpusles or thyic corpusles What is hassle corpusles We have a highland mass in the center and we do have some reticular epithelial cell which is surrounding them Dying epithelial reticular cells are present around it and that is called as hassel scorposal which is also the identifying feature of thymus But again if if you ask me personally I feel thymus is not that important from the hisytologology point of view It is most likely to be lymph node pelatin tonsil and the spleen But you know you never know about the exam but I'm just saying it's my my you know what why my brain says that thymus is probably not going to be asked because thymus can be confused with many other slides Okay Yes Perfect So guys that is about the lymphatic that is hassle corpus or thymic corpus present in the medula chera So that was about the embryology part and the upper limb and some hisystologology we have done Um let's continue break laying in beach but not now we we will take a break after around like 45 minutes or so Okay just just give me one second guys Let me just open the window here One second If you hear some sound of cars going from here to there just please excuse me I have to open the window because to keep this room a little ventilated Okay let's go to the to the lower limb break I I'll give you a break I'll give you a good 20 minutes break Not this 5 minute break I'll give you a 20 minutes break in between But not now Let's continue guys So in lower limb first guys look at this picture When you're looking at the posterior abdominal wall there's a muscle that you're looking at that is called the swast major muscle coming from the lumbar vertebra Look at the arrow over there Swast major muscle and there's a muscle coming from fossa called as iliacus Now swast major and iliacus muscle the two main muscle which is present on the abdominal wall They're going to help you identify the nerves coming from the lumbar plexus The poor lumbar plexus major feature present Lumbar plexus is found by the L1 L2 L3 L4 L5 nerves And this entire lumbar plexus lies behind SWAS major muscle So to identify the nerves of the lumbar plexus you just have to see how nerve is coming out Is it piercing SWAS major Is it coming out lateral side to the SWA major medial to the Swiss major How exactly it is coming out That that's how we have to identify it Okay look again the same picture I mean that kind of picture I hope you can appreciate the two muscles su major and iliacis Now first look at the nerve which is piercing If a nerve is piercing the swast major muscle and running on it that muscle is that nerve is generatoral I'll talk more about these nerve individually also Right now just try to identify them Genital femoral nerve is piercing the swast swast major and coming out Look at the nerve which is coming out between swast major and iliacus That's how we define the course of this nerve also femoral nerve It emerges between the swast and iliac muscle Sweiliacus and look at the nerve which is present medial to swast major that is operator nerve So the nerve piercing swast major muscle genital femoral lateral to swast major is femoral and medial to swast major is opterator nerve here Okay Then you can also see another nerve which is also running within the fossa within iliacus muscle within iliacus and then passing deep to the ligament that is lateral cutaneous nerve of the thigh Look at that lateral cutaneous nerve of thigh The compression of the nerve which causes mealgia paresthetica That lateral cutaneous nerve of thigh is running within the iliac muscle That's how you got to identify them here And then look at the nerve starting from above We are looking at the nerve called as sub coastal nerve not the part of low plexus that is T12 nerve subostal nerve And then we have the two nerve coming from L1 called as iliohypogastric and ilio inguinal nerve In that sequence first iliohypogastric and then we have ilio inguinal nerve iliohypogastric and ilioinguinal nerve Okay guys sub coastal nerve iliohypogastric nerve ilioal nerve all these nerves that looking at Oh there are questions on the genital femoral nerve and other nerves also But what you can use this picture as well for is to understand or to remember couple of relations also be look at sub coastal nerve ilio hypogastric and ilium on the other side I want to look at the other side These three nerves are forming the posterior relation of kidney nerve kidney post relation and that's why these nerves are vulnerable to any surgical approach to the kidney Obviously you're going to approach the surgically to the kidney from posterior side or pes the three nerve in the sequence sub coastal iliohypogastic ilium nerve the three nerves forming postulation of kidney Now look at the two nerve here genital three nerve genital femoral nerve lateral cutinous nerve and femoral nerve These three nerves obviously on the right side the left side may on the right side they are also forming the posterior relation of seeum or you can say secal bed they lie in relation to the seeum they're posterior to seeum three nerves genetal lateral cutinous nerve of thigh and femoral seeum So they're vulnerable to injury in the secal surgeries or when you approach the seekal or let's say the patient is having a retroal appendix then obviously you got to be careful with these nerves here And then we got a opterator nerve Opterator nerve is in close relation to ovary It is forming the relation to the ovarian bed The nerve forms the relation to the ovarian bed It is in relation to the ovarian bed Very close to the ovary And that's why in ovarian carcinoma the optimate nerve can also be involved and that can cause the weakness of rectal muscle that can cause the sensory loss on the medial side of thigh Pain can also be seen radiating on the medial side of thigh because of opterator So when you're looking at the I hope you can see that sound here Some Saturday evenings you know some people do get their sports car out and just test their speed on on road So you may hear all these sounds in between So I'm sorry for that So guys the what do you see this sub coastal iohypogastic illium while another three nerves forming the postulation of kidney Then we have genetic femoral nerve lateral femoral nerve forming the post relation of the seeum obviously on the right side And then opterator nerve is in the closed relation to OB here Relations questions Remember the lumbar plexus If you see a nerve present like if if if you think about the kidney it it is more logical for the examiner to ask you the posterior relation of kidney because surgical approach to the kidney is from posterior side So posterior relation of kidney retroal appendix is the most common position of appendix So that's why knowing the SQL relation is important Okay So guys this is about the uh of the structures which are forming some post relation Now from this lumbar plexus some of the some of the you know nerves need to be discussed slightly more detail because the questions in being asked and first question I'm sure you must have discussed this question with Dr Rajat in in pathology or somewhere else also that is a swast absis Here I just have to show you this picture because swast major muscle is the one which originates from the transverse process of the upper four lumbar vertebrae Look at on this side you can see the absis present along the muscle that is a swast absess and this question was asked in the in the in the in the recent time it was a radiological question The the thing about the SWAS absess is it trickles along with the SWAS major muscle and SWAS fasia or lesser troenter and because the swast absess can reach to the lesser troanter So it may give an appearance of the inguinal hernia also right it just may look like an inguinal hernia if you if you if you look at the swass absis when it kind of trickles down and reaches the the lesser troanteria So that just a picture to show that where the normal swast major muscle and how the swasts is going to look like on the posterior abdominal wall Yeah I know guys I'm not that expert to tell you whether it's a Bugatti or it's a Ferrari but whatever like okay now look at this nerve guys the nerve which is piercing the swast major muscle uh which is which is coming out but look at the nerve when the when when the genital sorry piercing the swast major muscle when you look at the nerve piercing the swast major muscle coming out it is dividing into two branches one of the branch is called as a femoral al branch and one is a genital branch The one which is more toward the lateral side it's the femoral branch of genet And the one which is more inside is a genital branch of genital femoral nerve Now femoral branch of genetal nerve it pierces the skin and comes out and it supplies the skin exactly over the femoral triangle Look at that area guys The skin over the femoral triangle is supplied by the femoral branch of genetal nerve So that's why when when we're testing the cremastic reflex when you scratch along the medial aspect of thigh you stimulate this nerve only that is a femoral branch of genital femoral nerve whereas the genital branch of genital femoral nerve it is going to supply the muscle that is a cremastic muscle and that is forming the ephr of the cremastic reflex question if the genital femoral nerve is the main nerve which is forming the eent and the aphrrent of what reflexic reflex and secondly because the femoral branch of genital nerve supplies the skin over the femoral triangle to femoral vein canulation If you're like you're putting a canula on the femoral vein you need to anestheize surface anesthesia to which nerve femoral branch of genetic femoral nerve So aphrant and ephrent of cremastic reflexes by the genetic femoral nerve That's one question And another question is that femoral branch of genital femoral nerve is the one which is anesthetized in femoral vein canulation In femoral vein canulation Okay Look at this another nerve guys What nerve is that here I I'm just I'm just like waiting for one second I want you to tell me guys what nerve is this here just based on how it is coming out and and running into the lower limb Tell me what nerve is this Come on quickly Yes Perfect Yeah you all are well prepared already That's the lateral cutaneous nerve of thigh guys Good answer guys That's the lateral cutinous of thigh How do we identify the nerve You can see the nerve obviously coming from posterior side of swast major running within the iliacus muscle and then it is passing deep to the inguinal ligament And while it is passing deep to the inguinal ligament sometime it is compressed deep to the inguinal ligament and that cause the pain and the like sensory pain and burning sensation on the lateral side of the thigh That is called as a mealgia paristhetica That is called as a mealgia paristhetica Right That is also a question asked about it Now genital femoral question surgery question it was about troker placement I don't remember the language of the question correctly but it was something about the troker placement troker and mesh was placed on in in some of the surgery of the abdomen and after that the while doing that a nerve is compressed somewhere in the posterior abdominal wall and the pain is radiating into the lower limb Question what is the catch here If the question says the pain is rading into the thigh that means while putting the troker maybe the nerve compressed is a lateral cutinous nerve of thigh But if the pain is radiating into leg thigh if the pain is ready into leg that means femoral nerve is compressed because femoral nerve will continue to form the sephinus nerve which is supplying the medial side of leg So thigh leg question important just don't think about lower limb which the the nerve which is carrying the pain sensation into the thigh is lateral kit of thigh the nerve which is basically responsible for pain sensation into the leg that will be the sephus nerve coming from femoral nerve So it depends upon that which nerve is most likely involved in that case what case is given to you Okay sir Moving on Now when you look at the hipbone guys the two major bony prominence that you can appreciate right now from from this here that is anterior superior spine and anterior inferior spine Now anterior superior spine as is the origin of the sartorius muscle and it also provides attachment to the inguinal ligament here Sartorius muscle origin and inguinal ligament is also attached to this point here Whereas a IIS anterior inferior spine AIS anterior inferior spine is the origin for rectus feoris But rectus humoris head the straight head of rectus femoris will come from here Reflected head will come from like from above the acetal but straight head of rectus feoris will originate from here So that is asis and ais not very important but I I feel that bony prominences especially in the shoulder region and into the hip region are important Then we have this greater troanter and lesser troanter Now when you look at the greater trocanter from the front when you see the greater trocanter from the front you may appreciate the attachment of glutius minimus muscle glutius minimus muscle is inserted there and glutius minimus muscle along with glutius medius med I'll show you the medius from the back side along with glutius minimus and medius both these muscles are responsible for abduction and internal rotation of the hip guys abduction and internal rotation abduction and internal rotation of the of the hip now if you look at the Same thing from the back side up pitch is there Now if you look at the hipbone and femur from posterior side greater trocanter is also showing you the attachment of the glutius medius muscle also on the lateral side of greater trocanter we have glutius medius On front of the greater roanter we have glutius minimus Minimus and medius muscle attached to greater trocanter not glutius maximus because glutius maximus muscle is basically attached to the tuborosity present here which is called as a glutial tuborosity It's on the shaft basically glutosity I told you glutius minimus So your glutius medius So the action of both glutius minus medius muscle is is abduction and internal rotation It's abduction and internal rotation Thank you Tushar Keep on keep pushing in between Yeah So greater trocanter if the question is about the greater trocanter fracture If there's fracture of the greater trocanter the obviously there's a loss of the glutius medius muscle and glutius minimus muscle and the patient will lose the inability to abduct the hip and internal rotate the hip abduction internal rotation be okay look at that guys that is the glutal tuborosity the glutial tuborosity on the posterior surface of femur is giving insertion to the glutius maximus muscle glutius maximus is a major extensor of the thigh major extension of the thigh it is not inserted on the troentry glute US maximus muscle is not on any troanter Then we have lesser trocanter which is giving insertion to the ilio The muscle that we saw earlier iliac and swast major guys Ilioas iliocus and swast major muscle together are called as ilioswas and both ilioswas muscle are inserted on the lesser trocanter and both ilioswas muscle are the major flexors of the hip Main flexor hip joint main flexion that is by the ioswas muscle only that is ilioswas right so this is about some of the attachment that you need to know here if you ask question about the fracture of the greater troanter fracture of the lesser trocanter so it's not just they will ask you the muscle which is involved in this they might ask you which movement will get affected that's why movement will get affected by that muscle involvement Okay I'm going to enjoy all these messages all the the the things that you're typing in between But after the session right now look at that spine over there guys Isel spine One of the recent question on the isial spine was what is the level of the isial spine The isel spine lies at the level of the coxial vertebrae But sacral coxix if the sacrum coxix is present over there So is spine is present at the level of the coxial vertebrae That was one of the question asked in the recent time What makes is spine so important The isel spine lies at the junction of greater shiatic notch and lesser shiatic notch There are structures some structures will come out of the greater shiatic notch and enters the lesser shiatic notch or because the structures which which basically need to leave the pelvis and enter into the perennium They are pin structures predendal nerve internal predendal vessels and nerve to operator internals These three structures basically are going to come from the greater shiatic notch enters the lesser shiatic notch or both pin structures p I pin structures pedal nerve internal pedal vessels and nerve to opterator internals especially pedental nerve is very important there because if the pedal nerve is injured on the isial spine the muscles of the perennium will get affected guys perennial muscle muscle paraneium bulbos spongosis isosis transverse panel external anal sphincter paranal muscles they will get affected If the pedal nerve is affected especially where at the spine I hope you read this in OBG also that is spine when you have to block the pend pendal nerve block is done against the spine also okay thank you guys thank you so much I'm deeply humbled by your messages thank you okay now ilotibial band or ilotibial tract what is ilotial band The name says a lot Ilotibial bones That is called as ilotibial band Now guys in the ilotial band this white color band that you see on the lateral side is IT band That is that that is the ilotial band over there This ilitial band is a thickening or the modification of facial lata Facial art is a defacial thigh So it's a modification of facial art The deep facial thigh This iliteral band There are two major muscle which are inserted on the elitable band One of them is a glutius maximus and one is tensor facial arter That's a question also that which two muscles are inserted on the IT band So one is TFL that is tensor facial L and glutius maximus muscle both of them are inserted to the glutius maximus guys it was inserted to the glutal tuborosity also that was a bony insertion it is insertion on the band as well So glutius maximus and tensor facial are the two muscle inserted on the IT band that is one question Another question that if there is a contraure of irritable band let's say the patient like post guys in case of polomiitis when there is a contraction of the elotable band what will be the position of the hip joint and what is the position of the knee joint your hip joint will come into the faber position fab flexion abduction and external rotation look at that look at that guys so in the hip joint there is what faber flexion abduction and external rotation and at the knee joint also there is a flexion external rotation of TV is also there TV will also externally rotate but I'll tell you the important thing is this flexion both the knee joint and hip joint will come into flexion hip joint flection or knee joint reflection that is because of this uh in this in the post polio contraction of the IT band here okay one more thing this abnormal positioning abnormal positioning of this the of the thigh flexion abduction external rotation it is a normal function of the sarus muscle Faber at the hip joint is a normal function of the satur muscle Sarterius muscle is responsible for the flexion at the hip joint abduction at the hip joint and even external rotation at uh external rotation of the hip joint also So it band contraction that is a normal function of sus muscle at the hip joint That's why if I take you to this picture where you're looking at the muscles of the anterior compartment of thigh this is atlas picture and that's a the caoric image here Now let's compare both the picture guys First whenever look at the anterior compartment of thigh first look at the satur being the key muscle over there When you look at the satur muscle you can divide the entire anterior compartment of thigh into two part Everything that you see medial to saturius that is all muscles of femoral triangle If you look at the muscle starting from like what I told you guys for the satur muscle is causing what fiber flexion abduction external rotation at the thigh at the hip and even flexion at the knee joint here So contraction of the IT band and the normal function of sus muscle is the same is more more or less the same Look at medial to start the another muscle let me go with that first another muscle that apart from sus is a big muscle that you need to know that is rectus femeris muscle Rectus femoris muscle is crossing the hip joint from the front Remember rectus femorous muscle was originating from the aiis anterior inferior spine So rectus femorous muscle will cause the flexion at the hip joint and extension at knee joint Hip for flexion guys This muscle will cause the flexion at the hip joint and extension at the knee joint the rectus simorous muscle which is exactly ult or opposite of hamstring muscles the hamstring muscles like semiendinosis semimebinosis muscle they will do the extension at the hip joint and flexion at the knee joint here So remember that rectus femorous muscle which is causing the flexion at the hip and extension at the knee is exactly antagonist to the hamstrings semmitendinos semiendenos semebrinosis all these muscle will cause the flexion at the knee and extension at the hip here If you look at medial to saturius now medial to saturius guys you are able to see the muscle that is coming from the eye was the iliacus you already saw that next muscle to that is what obviously what swas major you also saw that next to that is the we're going toward the medial side now pectinius and finally we have a muscle called as erector longus and iliacus swast major pectinus and erectoral longus these four muscle in that sequence from lateral to medial are all forming the floor of the hummoral triangle these four muscles are forming the floor of the femoral triangle triangle These muscles are the floor of the femoral triangle right that is floor of the hemor triangle that is the four muscles over there Okay So from this like in INIC they gave the muscle storius and the question was about the action of this muscle guys in the cateoric image based question I know that people generally are very scared of the cateoric picture So category image this category image that here But you know if you pick up if if you just look at the actual cateoric picture asked in the exam in the recent four five years you will notice one thing that question could be difficult They might ask you detailed action of the muscle or something but the image and the muscle asked is usually very simple Examiner is not that cruel They will give you muscle articular genome muscle to identify nothing like that It's a big muscle like muscle like biceps or triceps or any any you know brachurelis muscle muscle question on the pronis was asked in the exam the question on the sus muscle is asked in the exam to basic muscle this muscle you have to identify I'm pretty sure that people out of any muscle that you see in the picture the one muscle which I'm sure everyone is able to identify simply start muscle and that's even examiner no key I have to give a picture where the muscle is identifiable now what I can do is I can ask the question with a little twist I can ask you detailed action of the muscle or something about the nerve surface something So please don't be scared of the image based question because in the image based question the easiest part is the image The question might trouble you a little but when you look at the image you will not have a difficulty in identifying what nerve what artery what muscle what joint what ligament is shown to you that I can promise you that that's the history of this exam shows you although in the grand test in the in in the in the in the different uh tests which are available at different platform the question bank when we have to formulate the question different faculty have to formulate the questions they actually end up giving difficult questions difficult images here difficult images and trust me on Chir now now this is a femoral triangle guys that's a femoral triangle and we already saw the floor of femoral triangle now you look at the contents of femoral triangle the only thing I want to notice in femoral triangle very basic in this in the femoral triangle that's a femoral nerve which is a lateral most the major content lateral most content is femoral nerve and then we have femoral artery and the femoral vein but the thing is femoral arter and femoral vein are inside the femoral sheet that's the important thing femoral nerve is a content of femoral triangle But femoral nerve is not the content of femoral sheath Fmormoral sheath content may we have femoral artery We have femoral vein and we do have some lymph node also called as a lymph node of clockw But femoral nerve is not the content of femoral sheath here Right Yeah The femoral nerve So the the the relation is like for lateral to medial we have nerve then we have artery then we have vein So it's nav from lateral to medial But remember artery and vein are the one which are inside the femoral sheath nerve is just outside or just later to the femoral sheet in the femoral triangle That's what you have to remember in this Okay Now in the glutal region the questions in the glutal region it's not the glutal region questions are challenging because the question is generally about one muscle that is glutius medius muscle I mean that that's the most commonly asked question Let me tell you one thing guys they obviously will not give you the glut region picture like this because the muscle that you're looking at right now on the screen is glutius maximus glutius maximus intact So obviously the examiner has to cut the glutius maximus muscle and then show it to you So look at this picture now Now when you look at the glutus maximum muscle is cut on the other side here you just have to identify this muscle but that muscle is pyiformis You identify the pyroformis muscle and it is sorted Why I'm saying it is sorted because if you see the nerves and vessels coming out above the pyroformis those are superior gluten nerves and vessels If you see the nerves and vessels coming out below the pyroformis they're inferior glutial nerves and vessels And the muscle that you're looking at over there guys these muscle that muscle that makes all the difference This muscle say gluten push They ask you the question that muscle is glutius medius or maybe minimus also The reason glutius medius muscle is so important because as you already know glutius medius muscle is responsible for abduction and internal rotation of the hip Abduction and internal rotation especially abduction remember that So if glutius medius muscle is not working then guys glutius medius muscle of the right side is not working So every time I'll take the left foot off the ground my left pelvis will drop My right glutius medius is not working So my left pelvis will drop here So look in the normal condition this glutius medius muscle is working and that is maintaining the pelvis of the other side Look at the right glutius medius is working and left pelvis is leveled But if the superior glutial nerve which is supplying it if the superior glutial nerve is injured and the glutius medius or minimus muscle are not working then the right glutius medius injury will cause the left pelvic drop You can see that's a pelvic drop over there Can you can you see that arrow over there That's a pelvic drop and that is the trendelenberg sign Simple fun in Trendleberg sign or Trenleenberg test Everything is ipsilateral except pelvic This is a this is the right side glutius medius muscle It's a right side nerve injury It's a right side trenelber sign This patient will do the right side lurching also because the pelvic drop is on what side Left side So simple pelvic drop is on the contrlateral side in tendalber sign right side tendleber sign means right side nji right side muscle gone right side patient will do the right side lurching but the pelvic drop will be seen on the opposite side on the contrlateral side Okay Okay Coming to the nerve the one major nerve of the lower limb without which this topic is never complete that is the sciatic nerve guys the the sciatic nerve which is coming from this L4 L5 S1 S2 S3 lumbosacral trunk and S1 S2 S3 the first three sacral root values now the nerve runs into the glutal region then comes into the hamstring region and then this the shiatic nerve in the fossa that dime for fossa in the popo first the nerve the in the fora the nerve will divide into the common pal and tb the first the shiatic nerve in the glutal region passes deep to pyroformis guys It is not supplying pyformis It is passing deep to pyramis muscle It reaches the hamstring compartment It supplies all hamstrings All hamstring muscles supplied by the shihatic nerve Semiendinosis mebrinosis biceorus And then the nerve reaches the popl fora And in the upper part of the pop fossa only the nerve divides into the tibial nerve which runs straight and the common peronial nerve which is going to wind around the neck of the fibula Look at that The nerve which goes around the neck of the fibula that's a CPN common paranal nerve and after winding around the neck of the fibula the nerve is going to divide into a superficial and the deep paranal nerve Look at that That is a superficial paral nerve and the deep paranal nerve So now we have three nerves for the lower leg Tial nerve will supply the posterior compartment that is planter flexors Superficial paranal nerve will supply the lateral compartment that is everus and deep paranal nerve will supply the anterior compartment which are dorsif flexes Now TBL nerve is supplying the planter flexors which you and and I have to write this TL is posterior because TLS is posterior is the inverter also it is one of the inverter So TL is supplying guys leg So the posterior the calf muscles are supplied by TL nerve planter flexors which are doing the planter flexion and even some of the inverter also some of the inverter also superficial paranal nerve supplies peronus longus and perinus bis and ponus longus and peronis brievous areverters Okay And deep paranal nerve is going to supply the the dorsif flexors the muscles of the anterior compartment Tibial nerve after supplying the planter flexors after supplying the tibialis posterior What they're going to do in the foot they are going to divide into the medial plantar nerve and lateral planter nerve Medial planter nerve and lateral planter nerve which is going to supply all the muscles in the so foot So TB nerve is a big nerve guys because it is first supplying all the calf muscle and then supplying every single muscle in the solo foot Key superficial and deep paral nerve As you can see the superficial paral nerve supplies ever peronis longus and peronis ribs Deep paral nerve supplies the dorsif flexes the dorsif flexus and supplying tbellis antil which is a inverter The point is some inverters are supplied by the tbel nerve and some inverters are supplied by the deep paranal nerve Now what is the fate of superficial and deep paranal nerve Superficial and deep parano what they will do They will reach the foot The superficial paranal nerve the name says guys superficial that is a main nerve supplying the skin on the dorsome foot But the deep paranal nerve it just supplies the skin in the first web space The skin between the great toe and the second digit that space is supplied by the deep paronial nerve Now listen to this once again here Tial nerve supplies what compartment Posterior Deep paral supplies what compartment anterior and superficial panel supplies what compartment Lateral Now look at this If the TB nerve is injured now just focus on that guys If the TB nerve is injured then which muscles are Planter flexors are gone TBL is post inverters are gone If common pal nerve is injured at the necula which is the most common injury by the way if you look at here then we have dorsif flexors averters will be gone mainly Look at the consequences If the TB nerve is injured then we said which muscle mainly the dorsif flexors are mainly affected So I'm sorry planter flexes are mainly affected and the inverters are also affected So patients foot will come into what dorsif flex position andverted position dorsif flex and inverted and this dorsif flex andverted foot is a calccanial valgus and this patient as you can see is walking on heels only heel walk which is called as a calccanial gate The patient will have a gate called as a calccan walking on heel that is a kelkenal gate But if there is a common peral nerve injury now in common peral nerve injury there is a dorsif flexors and inverters are gone If dorsif flexors and inverters are gone then patient will have what Foot drop and inverted foot Drop and inverted foot is called as a eco aquininois position of foot Here foot drop and inverted that is auininois position When foot is equinaris in position this patient will take the very high step to clear the foot off the ground which is called as a high stepage gate So TB injury there will be calcul gate but in case of the in case of the of the CN injury which is more commonly asked question there's a high stepage gate will be there the high steepage gate will be seen two relations of the vein that you should know in the lower limb the great sephus vein and the short sephus vein the great sephus vein I'm sure you all know guys great sephus vein when it starts from the dorsom of the foot here it runs onto the medial side and the short sephanus vein it is running on the lateral side and it drains into the vein guys Great sephanus vein it drains into the femoral vein Whereas a short sephanus vein it drains into the popal vein The important thing is great sephanus vein cuz the nerve that you see running along with that is a branch of femoral nerve and that is a sephanus nerve It's a sephanus nerve which is running with the great sephanus vein So if you're taking a graft of the great sephanus vein in cabg then sephanus nerve is likely to get injured and the patient will have a sensory loss on the middle side of leg and foot till grade two But if you take a graft of the short stiffness vein then the vein nerve running along with that on the lateral side that sural nerve might get injured here and this patient might have a sensory loss on the lateral side of the leg and the foot right to the great sephanus vein sephus nerve and short sephus sural nerve present sephanus nerve present on the medial side it's the longest cutinous nerve in the body and sural nerve is present on the lateral side running with a short sephanus Okay Ligaments of foot and ankle guys What about the ligaments Just couple of ligaments of foot and ankle to conclude this lower limb part Mainly the some of the important ligaments which I want to mention here Maybe some of the ligaments are done discussed with you in the ortho class But if I may take your attention to some of the important ligament like this one guys Look at this ligament which is called as a spring ligament The reason we call it a spring ligament because it is supporting the head of the talis bone That bone over there is a talis bone and this ligament which is supporting it is a spring ligament Spring ligament is stretching between the calccanium and navicular This bone here is calcenium and this bone here is navicular and that's why this ligament is also called as a planter calccanium navular ligament Spring ligament is also called as a planter calcium navular ligament And I told you it's a main ligament of the medial longitudinal large This question is asked in exam that which ligament supports the head of the talis and that is the that is that is this what do you say spring ligament is there Then we have the ligament called as a long and short planter calccino cubuid ligament Honestly not very important because these ligaments are supporting the lateral arch So important ligament because lateral arch is not that concave like compared to the medial arch So out of these I would recommend you remember at least spring ligament that is planter calcium navular ligament supporting the head of the talis okay that is supporting the lateral arch not very important okay now again the same picture but this time this is a spring ligament if a pel this is a spring ligament but I'm not focusing on spring ligament look at the ligament called as deltoid ligament which is having three fibers look at the three bands of the deltoid ligament the question asked on the deltoid ligament is key which bone it is attached to deltoid ligament is attached to the tibia that's a tibial valus it is attached to the navular bone that is navular there it is attached to the calccanium and the posterior fiber are attached to the talis also so tibia be talis be navicular be calcenium be the deltoid this this delta-shaped ligament it's a very very strong ligament and this deltoid ligament is giving attachment I'm sorry this deltoid ligament is giving attachment is is attached to the medial melus to the navicular to the calccanium and to the talis bone here This is one of the old question asked by the puchawa question exam that deltoid ligament is not attached to which bone and medial uniform was given in the question in the option very strong ligament the injury is is it's not an not easy to have a injury to the deltoid ligament because foot injuries are usually on the inside inversion injuries are more common not the injury but if there is aversion injury at all like in ports fracture then you may have a deltoid ligament injured which is a rare thing to see it's such a strong ligament ligament to bone to that's how how strong this letoid ligament is But the ligament which is very vulnerable to injury guys is a ligament present on the medial side Now look at this ligament present on the medial side which is having one band on the posterior side one band middle and one is anterior and that is called as a lateral ligament of the ankle out of which the anterior talofi ligament is the most important We have posterior talopiar also we have this is a posterior talophibi This is calcci and there is anterior talophi But anterior talophibral ligament is more important to remember because inversion of the foot is inversion injury of the foot is more common And if there is a inversion injury of the foot the anterior talophibral ligament is most likely to get affected That's a question asked that which ligament injury is most commonly seen in the inversion in the inversion of the foot and that is anterior talofi ligament That that's an important question from this part here Okay Now when you look at the ligament of the foot one more ligament which I want to take your attention to guys and that ligament is called as a bifurcate ligament Look at that circle over there That ligament can you see the bifurcation there One band of this ligament is the stem of this ligament is attached to the kelken That's a calcium bone That over there is navicular and this over there is a cuboid So one band is going toward the navular bone One band is going toward the cuboid bone So this ligament is called as a bifurcate ligament And when you say bifurcate ligament you have a calcul navular ligament part of it from calcium to navicular and we have a calccano cuboid part of it In the inversion if the foot is in the planter flex position planter flexed foot if it is getting inverted anterior telophibral ligament is most commonly injured but yellow ligament injured This ligament is also likely to get injured in the inversion injury of the foot called as a bifurcate ligament There are two bands of this ligament called as a calccano navicular and calcinoid as you can see in the picture and that's a cadaaboric view of this bifurcate ligament here Look at that the calceniular calccano cuboid part and the calcino navular part of this burcade ligament here Okay slides and then I'm going to give you break after this guys Now look this is a picture of the cirrus acetas please understand that what I'm trying to show you in this picture when you look at the serious asinus go one thing is to be noted that I'm just enlarging this picture as much as I could If you look at the serious essence that's the maximum Yeah that's maximum Actually if you look at the serious SNS guys one thing if you if you note that look at this basil part here and look at this epical part which is granular and all the nuclei are present toward the basil side Can you see the all the nucleed nuclear present toward the basil side If you look at any SNS the nuclear present toward the basil side Yeah they're all present toward the basil side In the serrus SNS that is a thing to be remembered The cells are pyramidal Now you may not be able to notice the shape of the cell It is a very good picture That's why you're able to see rough endopplasmic reticulum are present at their bait That's why they're basic If you look at clearly it looks like a there's a blue line toward the basil site The basopilic cytoplasm is there because of rough ER there And we have epical region is having a the secretion granules are there The zamogen granules are there Then look at the mucus asinus In the mucusinus we have a foamy cytoplasm because when you treat the mucus mucus asinus with the alcohol the the mucus is washed off And the nuclei are flat and basil Look at the all the nuclei which are flat and basil nuclei are present here So in the nucleus and the cells are columar Again you may not be able to notice the shape of the cell but you can see the flat nuclei basil nuclei and the foamy appearance of the cytoplasm carrier So that's how the cirrus and mucus asinus generally they look like It's a very good image of the cirrus and mucus Honestly I'm not expecting need to give you the such a high quality images but we have to like when you Okay So and and that's a serious and the mucus there Just one second Lisf Frank ligament is nothing It is just connecting the medial ununiform to the base of second metar Medial ununiform to the base of second metatarsal That is lis frank ligament That is a list frank ligament complex Okay So once you know that how the mucus and cirrus is going to look like Now look at this gland That's a mixed gland Which mixed gland can aquas fomic cytolasmia So you can see the the the mucus also and cirrus also It's basically the mucus asinus is kept by the cirrus cells and it is called as a cirrus demill It's artifact guys It's artifacts while while when we prepare the slide this artifact is formed that is called as a mixed salary line where we have the serious devel are there mucus asinus they're carried by the serious cells now serious serious there is and I'm saying so much of serious seriousness again it is mainly because of this slide if you look at this picture this slide looks like a serious SNS rounded cell toward the basel side that's a serious asinance so looking at this okay it's a serious SNS this could be paroted gland no sir It's not peroted gland When you look at this slide it is not a parot though it looks like a paroted gland because these are serious asinus and paroted is a cirrus gland But this is not a paroted gland It is a slide of a pancreas When they give you the slide of the pancreas there are very good chances that they will give you the a lightly stained zone separately which is basically showing you the eyelet of langarance something like this This is the like eyelid you can see in this picture that that's the eyelid of langarance So maybe by looking at the eyelet of lang you can identify it is pancreas But let's say if the examiner is very cruel and is not giving you this region and giving you the only picture that you see in the corner above and you still have to identify pancreas Yeah it is a paroted gland Then the thing is if you look at the cell guys if if you look at this cell can you see some nuclei present in the center also Can you see some nuclei present in the center also Can you see some nuclear present in the center also In the SNS we have some nuclear present in the center and these cells are called as centroinar cells Now that's the feature guys forget about this island of lang problem but if it is not given look at the SNS and look at those cells present in the center these are called a centroar cells the duct if this is a SNS and this is a duct it should be like SNS is there and then we have duct starting like this but imagine if the duct is starting inside the SNS only So you will see that the the the the cells of the duct can be seen within the cirrus SNS only and these cells are called as a duct cells of the of of the SNS centroin cells that is a feature of the pancreas parotid gland slide to you will not see any cells in the center you will only sell see cells on the side only that's why these two are the most confused slide to each other if the eye of langarus is not given pancreas or peritude identify both See this SNS only but if you see some nuclear present inside the SNUS market pancreas these are cells are called as a centroar cells are central cells what is this again it's a previous picture for cytoplas look like it's mucus it's not a mucus asinus yeah asinus first of all look at the cluster of these cells there is no lumen present over there and they are present close to the root of the hair follicles these are the sebaceous gland guys sebaceious glands I'm sure you read about se cbious glands are the one which are holocrine gland question as much they have given this picture that what kind of secretion is seen in this in the sebaceious gland which you're looking at over there the kind of secretion is what holocrine secretion the cell itself will disintegrate into the secretion here that is called as epiid epiid epiid in pathology are the macrofasic cells those the the macro these the big macrofasic cells which is called as epiids you in general hisystologology Epiloid is a name given to the cells which do not have free surface The cells which do not have free surface Look at all these cells are clustered together They don't have any free surface They're all facing each other Like in eyelet of langarans it's epiids Sebaceous gland epiids Uh the the the cells of corona edita around the om the epiids Leading leading cells epiid These are some of the examples of epiids The cells which do not have free surface in cells free surface They're all facing each other only and that's why there is no free surface of these cells These are called as epiid So there are two different epi one is the ep the macrofasagic cells that you said read in pathology those are different epiids In pathology al in in general hisystologology also there is term called as epiid Epithelium achiepheric epiid Epithelium is a lining epithelium with a free surface Epiloids are the cells which without free surface these are called as epiid Even sebaceious gland is an example of epitheloids Without surface without free surface Exactly So now let's start with the head neck and face Um in head neck and face I'm going to start I'm going to go in the in the series of how I go in my lecture So I'll start with the cranial of nuclei and cranial of columns and some parasympic gang first So guys like look in the cranial of nucleon column Now the first thing I mean because it's it's a it's a oneshot program so we don't have to go into the details of how these eer columns columns are formed So in a simple way if you know the first three epherent column the first three epherent general somatic epherent special visceral epherent and general visceral eent if you know the first three here then you know the next three also because they are like mirror image only like for this GVE for this if this is GVE here one second there is GVE so we have a corresponding GVA for SV this is corresponding SVA and for this GSE there is corresponding GSA so three E friend and three apherent column there is one more they look you're looking at right now okay uh so GSE SV GV and then we have the three columns the aphrant columns the go GSE general somatic ephent guys the general somatic the word somatic is for the extraocular and tongue muscle the extracal muscle and tongue muscle the somatic muscles so third nerve nucleus fourth nerve nucleus sixth and 12th 3 fourth and sixth nerve will supply extracular muscle and 12th nerve will supply the tongue muscle they'll supply the tongue muscle right so they are the one which are present in first column But the first column can the nuclei which are present in first column are the one which are basically supplying extra occular and tongue muscle SV special visceral epherent Now special visceral eph is about fangial arches Fangial arches are supplied by what nerve We have mandibular nerve for first arch We got a facial nerve for the second arch And we have a nucleus ambiguous It is a combined nucleus of 9th 10th 11th nerve cranial accessory That nucleus is called as nucleus amicus that is for the ninth limit nerve So first column we have we have nucleus supplying extra and tongue muscle Second column we have those nuclei which are supplying the fangial arch muscle Then the first two column the the similar thing about the first two column is the dono column are to supply the what muscle skeletal muscle They're supplying skeletal muscle and that's why we have a third column that is general visceral leaf General viserant is to supply the smooth muscles and glands Now when I say smooth muscles and gland they are supplying eding westfal superior salivary inferior salivary dorsal nucleus of Vegas We'll talk more about this column here but this is the column which is basically this is the column which is going to supply the extra going to supply the smooth muscles and gland and that's why this column is also called as a parasympathetic column I'm column detail discuss we'll talk more about this column separately in detail Edinger Westfall the two salivary nucleus superior inferior salivatory and dorsal nucleus of Vegas that's epherent now coming to aphrant column the GVA SV general visceral apherent and special visceral apherrant general sensation viscas yeah taste sensation viscas they will all come into one nucleus only and that is called as a nucleus of tractus solitarius it is the only nucleus present combined in two column just imagine how important this nucleus is for two column we have one nucleus called as the nucleus of tractor solitary Nucleus of tractor solid NTS Okay Okay Then we have a column called as the GSA column Go just break it down General somatic aphrant General because general sensation somatic that means from body wall from the skin from the dermis from the muscle body wall sensation aphrent So any nuclei which is going to take the general sensation from body wall will come into this GSA general somatic afrant So there is a trigeminal nuclei here This big nucleus here Again I'm going to discuss this nuclei more in detail It is called as a trigeminal nuclei having three parts that is present in GSA column Right General somatic aphrant Despite of having these six columns we have one more column after that guys and that is called as SSA column Special somatic aphrant column SA special somatic aphrant column is a column for the vestibular and clay nuclei special sensation be but they're coming from somatic structures So we have a separate column for vestibular and nuclei vestible or vestible and nuclei right these are the columns we have now I know that in the exams they're not going to ask you all these columns in that kind of detail one important column will be GV one is GSA column discuss see the nerves which are parasympathetic in nature they are more important nerve to be asked in the exam parasympic nerve concept 3 7 9 and 10 3 7 9 10 are parasympathetic I'm sure everyone knows that now third nerve you can see third nerve comes into the GSC column And third nerve belongs to Edinger Westfall also So there are two columns for third nerve that is GSE and GV Third nerve though column guys that is G SE and GV GSE and GV is the column for third Seventh nerve ninth nerve and 10th nerve Now that is easy Seventh nerve ninth and 10th nerve are related to all columns except first and last Look at that All these columns first leave the GSE and leave the last column that is S SSA leaving first and last column All other columns are related to the to the seventh nerve to the ninth nerve and 10th nerve Nobody in the exam is going to ask you the reason for that You just need to know the answer which columns are related to the seventh nerve ninth and 10th nerve All you have to think about here sorry column except GC that is first one except the last one that is SSA all are there and I already told you that for third n we have two column that is GSC and GV GSC is there and GV is there that is for third nerve So out of all the cranial nerves at least at least remember these nerves that is three 7 9 and 10 But let's not stop here guys let's talk about every cranial nerve Now look at this picture here First GSA column general somatic aent we said what is what is there in the general somatic aphrant column In a general somatic aphrant column we have this big nuclei called as a trigeminal nuclei And this trigeminal nuclei we said it is having three part One is called as a misaniphalic nucleus guys Misenyphalic nucleus which is present in midbrain Then we have principal sensory nucleus which is present in pawns And then we have spinal nucleus which is present in the medula and it even goes till the C2 level of the spinal cord It even goes to the C2 level of spinal cord that is misenphalic the spinal nucleus here Misanphalic nucleus is responsible for receiving propriception Principal sensory nucleus receives touch and pressure and spinal nucleus is the one which receives pain and temperature Pain and temperature Misenyphalic nucleus is an important nucleus This is something which is repeatedly asked in the exam because misanphalic nucleus It is not just the nucleus for propreception It is a nucleus for the jaw reflex or measetic reflex and is the only site a site central nervous system may which is having pseudo uniolar neurons are there guys It is a center for jaw reflex Number one It is center for the jaw reflex misphalic nucleus and it is the only site for what neuron pseudo ununipolar neuron in CNS outside CNS example inside CNS it is the only example where we have pseudo uniolar neurons that is misen syphalic nucleus it's an important question and they've asked this question more than once so that is something about the gsa column the big trigeminal nuclei is there and that's a function of these individual nuclei especially misphilic nucleus is important now coming to the gve column guys third colum column GV this we have got edinger westfall superior salivary inferior salivary and dorsal nucleus of vagus now eding west vestfall is there superior salvator nucleus inferior elevator nucleus that is in the pawns and we have a dorsal nucleus of vagus what these nucleus are doing which nerve they are connected to what ganglion they're going to relay in which gland they're going to supply let's discuss that edinger vestal as I'm sure you all know eding west vestal the nerve for the edinger westwal is a third nerve So it's a third nerve which is basically carrying this uh you know information from the Edinger vesal nucleus It is going to relay into the ganglion Which gang guys Celery ganglion That's a celery ganglion And then from the celery ganglion the multiple short celery nerves will come out and these short celery nerves will go out and supply the sphincter pupil and celeris muscle So that's the function of Edinger Westfall The general visceral epherent can the pala column pela nucleus that is adinger westfal nucleus which is having a nerve third nerve relays into the celeric gulion and that supplies sphincter pupil and celeris muscle superior salivary nucleus the nerve for superior salivary nucleus is facial nerve and this facial nerve divides into two branch I mean I'm talking about two branches of facial nerve one of the branch of facial nerve that I'm talking about is a greater petroal nerve GPN this greater petroal nerve it relays into the new ganglion which is called as a Terrigo pelatin gangon sub gang it's the largest parasympathetic gangon that is terrigo pelatin gangon and once the greater pitrosen relies into teropelin ganglion the post gangonic fibers will go and supply lemal gland and some supplies the nasal gland also but leaval gland is important to remember but it's leaval gland and even nasal glands are also supplied by this necal nasal gland another branch of facial nerve guys another branch of facial nerve is codmpony now cordatony nerve also O goes and relays into the new into I'm sorry relays into the ganglion and this time the ganglion is the submandibular ganglion It's a gangon which is present somewhere here submandibular gangon and once it relays into the submandibular ganglion the post gangular fibers are going to supply the submandibular and the sublingual gland supply submand sublingual gland This also helps remember that the facial nerve guys facial nerve response facial nerve is one nerve connected to two ganglion two parasympathetic ganglion and it is responsible for supplying lacrimmal gland nasal gland submandibular sublingual gland Majority of the glands are supplied by the facial nerve only using two ganglion that is teriggoatine and submandibular ganglion Then comes inferior salivated nucleus The nerve for the inferior salivated nucleus is facial nerve The ninth nerve sorry glossopherial nerve to be more precise Jacobson's nerve and lesser petroal branch then ninth nerve this ninth nerve via lesser petroal nerve relays into the otic ganglion this time the ganglion is otic ganglion and the post gangling fibers from otic gangon are going to supply the paroted gland guys it is for the paroted gland here so in a way I can say facial nerve takes the responsibility of of the lacrimmal gland nasal gland submandal gland sublingual gland but perot gland is a responsibility of what nerve ninth nerve so facial nerve supplies most of the glands in head and neck but ninth nerve will take care of the perot gland Dorsal nucleus of Vegas guys dorsal nucleus of Vegas name says it's a vagus nerve coming out from there and the responsibility of the vagus nerve is to supply the smooth muscles and glands in the thorax and abdomen So no it it's not there is no ganglion for vagus nerve in head and neck The ganglion for vagus nerve are lying in the thorax and abdomen because the responsibility is to supply the smooth muscles of thorax and the abdomen So this is something about the Yeah Yeah This is about the the GV column It's an important column This column is question They can ask you that which first of all it's a parasympathetic column guys Number one it is related to parasympathetic Look at the third nerve seventh nerve ninth and 10 These are all parasympathetic cranial nerve They can ask you which which nucleus is connected to what nerve which gang they will relate to what gland is supplied by them So I I I feel there are a lot of questions which are present on this slide here So please make sure that you when you revise it just revise it carefully Moving on we already said parasympathetic nerves 3 7 9 and 10 Now if I talk about all cranial nerves from 1 to 12 Now which column they will lie to first and second nerve So there is no nuclear for first and second So forget about it Third nerve we already said third nerve belongs to the GSC column and GVE column That was easy Okay If you think of fourth nerve guys fourth nerve supplies only extracular muscle and nothing else And extracular muscles come into the GSC column So fourth nerve is only having one column that is the first one GSC column is there Fifth nerve Fifth nerve if you remember fifth nerve comes into the second column that is SV because it is supplying the muscles of mastication And fifth nerve also trigeminal nuclei Trigeminal nuclear lies into what column GSA column guys GSA column is also so there are two column for fifth nerve One is SV to supply the muscles of mastication and to take the sensation from face the trigeminal nuclei The GSA column is there Sixth nerve again I told you sixth nerve guys we only have one column It is supplying lateral lectus and that's it So only again first column GSC column is there Sixth nerve nothing else Seventh ninth and 10th nerve What I told you guys 7th 9th and 10th nerve they have all columns except first and last Look at that Look at the check over there The ticks all 7th 9th and 10th All the columns except first and last First name last name column eighth nerve Remember when we drew that table what was the last column The last column was S SA column Special somatic aphren So eighth nerve vestibular cular nerve belongs to this SS SA column Special somatic aphrent column 11th n Now that's interesting because this is I believe that they can kind of trick you on 11th nerve also comes into two column column Say because 11th nerve is having two part one is cranial accessory and one is spinal accessory Now guys craninal accessory nerve comes into this part that is cranial accessory here but spinal accessory because it supplies the skeletal muscle the somatic muscles outside So it actually comes into GC although we are not able to see it in the on on that on the table because the table belongs to only brain stem This is beyond brain stem the spinal accessory nucleus is present in the spinal cord but remember that the spinal accessory nerve that is cranial accessory but the spinal accessory nerve they belong to the GSC column so the first they are for the 11th nerve 11th nerve that that is that's a tricky part here 11th nerve is having two column first two column GSC and SP and 12th of hypoglossal nerve again hypoglossal nerve just supplies what tongue muscles and tongue muscle that is the first column only that is GSC column that's it although you're looking at all the nerves and their column here But I still tell you guys only focus on third 7th 9th and 10th 3rd 7th 9th and 10th here 3 7 9 and 10 The parasympathetic cranial nerve are the one for which you have to remember the column say column that is still okay That will do Yeah Mayang is focusing on Bugatti only outside Bugatti is not a very famous bike here You know Bugatti is a or bikes are other super bikes are better So guys rule of 17 in the cranial injuries the rule of 17 is something which is which is very important uh to to to know about because a lot of image based question can be answered from this rule of 17 Now when I say rule of 17 guys it means 10 + 7 is 17 12 + 5 is 17 You all know about the rule of 17 I be 10 plus 7 we have written together because 10th nerve and seventh nerve if there is an injury to 10th nerve and seventh nerve the deviation will be seen toward the contrlateral side If the right side nerve is injured the structure will deviate toward the left side Similarly in case of 12th and fifth nerve when 12th and fifth nerve are injured the deviation of the structure will be seen toward the ipssilateral side 10th when you look at the 10th nerve can you see this picture The u is deviating toward what side The ua is deviating toward the left side in this picture That means it's a right vagus num injury If you look at this picture facial nerve look at the angle of mouth guys Corner of mouth it is deviating toward what side Left side It's a left deviation of the corner of mouth So it is a right side facial injury because strong muscles are pulling So it makes sense 10th nerve and seventh nerve injury may the deviation is seen Sorry for that sound away from the away from the nerve side Right Then we have 12th and fifth nerve 12th and fifth nerve In case of 12th and fifth nerve the deviation will be seen on the ipssilateral side Now the tongue deviates guys If you ask the patient to protrude the tongue and if you see the tongue deviating toward one side whichever side the tongue is deviating there is case when the tongue is deviating toward the left side So left side hypoglossal injury is there And similarly like in this case if the jaw is deviating toward the left side it's a left side I'm sorry it's a left side trigeimal injury So it's it's very but remember in both these cases where the ipsilateral deviation is seen you have to ask the patient to do something like in first case you need to ask the patient to protrude the tongue then only you can see the deviation In this case you need to ask the patient to open the mouth When you ask him to open the mouth then you see the jaw is deviating toward one side But if the tongue deviates to whatever side or the jaw is deviating to whichever side the same side nerve injury will be there So it's a very good qu picture from area from where the image based question can be asked They might give you a picture and they will ask you that which nerve is injured and which side nerve is injured here So you have to say ipssilateral or contrlateral deviation based on the rule of 17 Yeah The tongue licks the wound Yeah No to exactly the tongue licks the wound Push effect Yeah Christian right Okay Now the transverse section of neck guys One of the one again one of the the famous question asked Now in the transverse section of neck the knowledge of the deep cervical fasia is important to identify the spaces number one and number two to identify the nerves inside Now first look at the spaces guys If you look at the picture this here is the fairings and the fasia that you see which is present just behind the fairings that fasia is a boofarangel fasia You all know fax is covered with the boofarangel fasia Then look at this fasia guys which is present in front of the vertebral column In fact it's not just in front of the vertebra column It is covering all this prevertebral muscle That's a prevertebral fasia This fasia is prevertebral fasia or in between the booking and prevertebral fasia That's another fasia present over there called as aller fasia So between the fairings and the vertebral column I hope you can appreciate the three fas there So we have buopharangial we got a allar fasia and we got a prevertible fasia Now the space which is present between the bukopharangial fasia and allar fasia guys that is called as a retrofarangial space It space is closed below So it's not dangerous but the space present between the aller fasia and prevertebral fasia is a dangerous space of the neck one of the pyq guys the reason we call it dangerous space of neck because this space is not obliterated below so this space of the neck continues into the posterior medastinum or a space diaphragmata it goes to the diaphragm guys so it opens below the diaphragm and that's why the infection of the dangerous space of neck can reach the posterior mediastinum it can compress the esophagus it can compress the trachea can cause dysphasia and disna also So that would say infection absess descends down into the posterior and they can cause dispas and dis That's why it is called as a dangerous space of the neck Okay Okay That was same picture again but this time in this transverse section we are not focusing on the fasia We are focusing on the nerves inside here Now nerves very important guys See now just I want you to f look at the image and look at the some circles which will come in here Look at the first circle there guys Can you see a circle there Now that circle that end circle over there that's what I'm talking about this circle here is basically present in the tracheo esophasial group between the trachea and esophagus Look at the another circle which is present inside the keroted sheath Look at another circle which is behind carroted sheath behind carroted sheath but in front of prevertible fasia or between the keroted sheath and prevertible fasia between keroted sheath and prevertebral fasia Another circle there which is behind prevertebral fasia this time but in front of the muscle that is skeleanus antior skelinus antior muscle and then finally between skeleanus antior and skeleanus medius there's another circle there here so look at these five circles that we have here and let me start with the first the first circle that you're looking at guys which is between the trachea and esophagus in tracho esophasial groove recurrent langel nerve will be seen here tracheo esophasial groove may whether it's a image based question or they ask you like theoretically the tracheo esophasial nerve to you know it's a recurrent langial nerve Then look at the nerve which is inside the keroted sheath The main nerve is vagus nerve that is inside keroted sheath Then you have the nerve which is sandwiched between the keroted sheath and prevertebral fasia That is the sympathetic chain between kerotation and preverteal fasia Then you see something which is behind prevertebral fasia but in front of skeleanus anterior Look at that That is what frenic nerve Very important guys Frenic nerve It runs anterior to the skelinus anterior but posterior to prevertal fasia or you can say between the preverteal fasia and skelinus anterior which are present that is a frenic nerve And finally you will see the cervical nerves C5 C6 C7 C8 all the cervical nerves which are going to form the roots of brachial plexus emerging between skeleanus antior and skeleanus medius So these are cervical nerves which are forming the roots of brachial plexus and they are the one which emerges between the skeleanus anterior and scalinous medius muscle muscle that is skalinus anterior and this one is skinus medius that is skinus this is skalinus anterior and this one is skelinous medius muscle in between them we have this cervical nerves which are going to form the brachal plexus yes good answer guys yeah it's it's good that you are answering simultaneously as well so in the transverse section of the neck this is some this is minimum that is expected from you to identify the retrofarendial and the dangerous space of neck and make sure you identify every single nerve especially nerves guys because what they will do they will formulate a clinical question out of it question there is a difficulty in breathing that is because of which nerve of the frenic nerve to identify the frenic nerve in that there's a patient who's having uh the gut mobility is reduced because of vagus nerve involved vagus num that is inside the caroted sheath the person is having difficulty in foration because of recurrent lendulum carcurren in tracheio groove so the question might be clinical but you might have to identify the nerve in the transverse section In this transfer section one topic which needs a special attention because that is asked separately in the exam and not like more than once is the keroted sheath If I take the keroted sheath out of this picture guys and you'll notice one thing that when you look at the keroted sheath the contents of the keroted sheath we have common caroted artery we got internal jugular vein we got vagus nerve that's a main main structure present inside here but is it the only thing present inside commonoted artery internal caroted artery internal jugular and vagus nerve look at that even ninth nerve 11th nerve and 12th nerve are partly present inside these nerves are just crossing the keroted sheath if this is my koted sheath here if a nerve is going to cross through it It is a content only Now so even 9inth nerve 11th nerve and 12th nerve are partly the content of kot Veagus nerve is a main content No doubt about that But even 9th 11th and 12th nerves are also traversing the kerotic in the upper part So they're also counted as content The anterior relation of kerot What is anti- relation guys Exactly adherent to the antior wall of keroted sheath is an cervicalis Look at the two dots over there There is an cervicalis which supplies trap muscle That anthoservicalis is adherent to the anterior wall of the kerotic sheath Whereas a posterior relation of keroted sheath we just saw what was a posterior relation guys sympathetic chain Sympathetic chain is forming the poster relation of the keroted sheath here So keroted she is something which is which is asked guys first of all the caroted sheath is an extension of different fasias Investing layer investing layer pre-traal layer prevertebral layer All the major fascias together will give rise to keroted sheath So keroted sheath is an extension of investing layer pre-traal layer prevertebral layer Keroted sheath is enclosing common carroted artery internal corroted not external corroted common corroted internal carroted jugular vein internal jugular vein and 9th and 11 12 No let me say 9th and 11 12 no So 10th is the main nerve here Anti-reation post some author even say an cervicalis as a content of a kerotic sheath because ano cervicalis is not just the anti-reation it is adherent It is submerged in the anterior wall of the kerotic sheet that is an cervicalis which is supplying the strap muscles Another important point from this from this deep cervical fasia that you should know about is a rule for the investing layer Investing layer of deep cervical fasia follows a rule called as a rule of two Now when I say the rule of two guys rule of two that means the investing layer is enclosing two muscles that is the sternocltomastoid and the trapezius It encloses two glands that is parotided gland and submandal gland Remember not thyroid gland People do commit this mistake guys Thyroid gland is present in pre-traal fasia Please don't forget this Thyroid gland is in pre-traal fasia It's the parotid gland and submandibular gland which are in the investing layer Easy way salivary glands Celivary glands are inside the investing layer Perot gland and submandal gland The salivary glands are present inside the investing layer Two glands Two spaces Investing layer is forming one space here that is called a supra sternal space and it is forming one space above the clavicle here that is called a supraclavicular space here So we have two spaces also which are made up of this investing layer Two ligaments stylo and spinoandibular the two ligaments which are all modification of of this investing layer These are the two ligaments of the TMJ temporal mandibular joint Styo mandibular from styid to mandible and sphino mandibular spine of spinoid to the mandible spinoandular ligament And finally the two pulleys the two pulley guys which muscle will need a pulley the muscle which is having double belly digestric muscle omohy muscle are the muscle having two belly so those two pulleys are also the pulley are also made up of the investing layer So rule of two two muscles two glands two ligament two spaces and two pulley they're all made up of investing layer of deep cervical fasia They're all made up of deep cervical fasia exactly Yeah So that was all the deep cervical casia Now into the dural venus sinuses guys I'm sure you read about the dural venus sinus but obviously nothing is more important than cvernous sinus Now it's the coronal section of cavernous sinus you're looking at on the screen right now Now in the coronal section you'll notice that there are nerves which are in the lateral wall of cavvernous sinus And that nerve in the sequence we have a third nerve We got a fourth nerve We got aic nerve and we got a maxillary nerve So these are the four nerves in the lateral wall of cavernous sinus Third fourth v_sub_1 and v_sub_2 in the lateral wall In the lateral wall the one nerve which is present inside cavernous sinus along with internal coroted artery that is a six nerve guys Six nerve and internal coroted artery is inside the cavvernous sinus If the question is asked to you that which nerve is most commonly affected in the cavendary sinus thrombosis to obviously six nerve the nerve which [Music] is the nerve which is inside the keroted sheath is the inside the cvernous sinus that is the that is abdusen nerve Sixth nerve is the one which is basically most commonly affected in this cavernous sinus thrombosis here Even internal keroted artery present inside the cavernous anus is an issue I mean it's an advantage also because it dampens the pulsation but it's an problem also because if there is an aneurysm of internal keroted artery and that is ruptured So there is a formation of fistula called as a kerotido cavernous fistula Because of this kerotto cavernous fistula what will happen The blood of the internal carot artery is filled inside the cavvernous sinus and every time the internal kerot artery will pulsate the entire cavernous sinus will also pulsate and that is going to push the content of orbit also causing pulsatile proptosis also guys you can see that picture over there you can see that that that's the that's the blood of the internal carot artery filling inside the cavina sinus you can see over there right that's the one right and that is a kerotto cavus fistula and kerotto cavus fistula give origin to this can can you see this pulsating eyeball That's a pulsating proptosis or pulsatile proptosis That is an indication If you see it's not pulsate it's not exothalamus The eyeball looks normal It's a pulsatile proptosis So if you see the eyeball is pulsating that's an indication that this person internal carroted artery might have ruptured inside the cabinous sinus which is pushing the content of orbit as well Exactly Moving on Now coming to muscles of mastication in head neck and face Again if if if you have to again you know kind of categorize the topic there are many topics which looks very important but muscle of mastication definitely wins the race guys muscles of mastication to whether it's inacc or knee exam out of all the muscles in the human body from the anatomy point of view the most commonly asked muscles are the muscles of mastication So obviously you got to do them carefully Now the muscles of mastication you always have to orient the muscle how it is running toward the mandible like the muscle that you're looking at right now on the screen that is a temporalis muscle muscle temporalist muscle coming from temporal fossa and you can see this muscle is converging toward the coronoid process guys that process where it is inserting is a coronoid process So when the temporalist muscle will contract it is going to elevate the mandible one it is going to lift the mandible up So it is one function is elevation and it is going to pull the mandible back also that is retraction and that's the two function of temporalis muscle elevation and retraction Elevation is a strong function of this temporalis muscle but the unique function of the muscle is what Retraction There is no other muscle of mastication which can cause retraction A temporalis which can pull the mandible back Retraction is a unique action of the temporalis muscle The next muscle over there is the meator Now if you look at the meator muscle present on the outside again the insertion is always on the mandible guys it is inserted on mandible So when when you when when you touch this mandible on the side you clench your teeth when you touch on the side this muscle on the side is meet only So this meet muscle the strongest muscle of mastication when it contracts its main job is to elevate the mandible It slightly protrude the mandible as well but the major action of the meat muscle is elevation It's the strongest muscle of mastication You can again see the direction is upwards The muscle is going to pull the mandible in the upward direction It's the main muscle for elevation If I remove this muscle I will see mandible If I remove the mandible I will see one muscle inside which is oriented in the same way only Just like this mess muscle and the name also start with M That is medial terid muscle Look at the guys muscle medial teridot This muscle inside that's a medial teroid muscle here right that's another one the lateral teroid So medial teroid muscle is oriented the way the meator muscle is and that's why the action of middle teroid muscle is also like me that is also mainly for the elevation Both meator and middle teroid muscle they can help in protrusion as well but the main action is the elevation And then we have the finally the most important muscle out of all the muscle of mastication this wins the race guys The maximum time the question asked is on the lateral teroid The lateral ter muscle is running backwards If you look at the the the biomechanics of this muscle when it contracts it it pulls the mandible forward So it's a muscle for protraction and it's the only muscle which is going to pull the mandible downward It is going the depression The unique action protraction and depression Protraction and depression is the action of lateral teroid muscle It's the major protractor main protractor Okay And the depressor that there's no other muscle which can cause depression Protraction can be done by the metor also and medial terod also partly but depression muscle So unique thing about this muscle is depression here right depression is the main action and the unique action of this muscle here So if they ask you these muscle individually that is have to you have to deal with it If you try to mug up these muscles you'll forget them Try to look at the direction of the muscle fiber and based on that you can answer it here So look at the like make a picture in your head how temporalous muscle is oriented Message and medial teroid muscle are both in the same direction One is outside one is inside the mandible And lateral teroid is going backward So it is going to protrude the mandible and open the jaw it is going to open the jaw The most common dislocation of the mandible I hope you know that's a anterior dislocation and anterior dislocation can be because of excessive opening of mouth like yawning Yawning may you can it can lead to the anterior dislocation Now another one more topic that I need to tell you from the head and neck which is from the exam point of which is important in the triangles of neck It's the posterior triangle and something very specific in the posterior triangle I want to tell you guys here the in the posterior triangle the muscle in the posterior triangle I hope you know that that muscle over there is a sternocltomastoid muscle right this muscle is a trapezius muscle and the muscle which is dividing the posterior triangle that that muscle over there is a inferior belly of homohide now there is one nerve that you see which is emerging from the posterior border of sternoclto mastoid and this nerve is going to run along over the sternoclto mastoid going above and this important nerve is a great oricular nerve Very very important question great oricular nerve Why great oricular nerve is important guys Great oricular nerve is the root value C2 and C3 There are a couple of branches for this great oricular nerve There are multiple questions asked in the recent past and they all belong to great oricular nerve Now look first of all the nerve great oricular nerve it goes above and I told you the root is C2 C3 This great audicular nerve runs along with the external jugular vein That's a neat question guys Which nerves runs on the side of the neck along with external jugular vein So if you're doing any intervention on the external jugular vein you got to be careful for what nerve great oricular nerve can get injured Number two this nerve supplies the lobule of the ear This nerve supplies the angle of mandible and it also supplies the the skin this peroted area skin which is also called as a shaving area It is a recent surgery question also that the patient have a sensory loss which he felt while doing the shaving So which nerve was injured in the peroted surgery Great oral nerve because it supplies the lobul of the ear It supplies the skin at the angle of mandible and this peroted region which is basically the shaving area here like in the shaving area also the great oricular nerve is important because guys in peroted surgery I I'm sure you all know in peroted surgery oricular temporal nerve commonly injured if oricular temporal nerve is injured that regenerating oricular temporal nerve is likely to fuse regenerating oricular temporal nerve is likely to fuse with great oricular nerve it is very likely to fuse with the great oricular nerve that is oricular temporal nerve can fuse with other nerve also like buckle nerve lesser oxipital nerve but most commonly the oricular temporal nerve fused with or communicates with great orical nerve that's why patient can be seen sweating on this area on the perot area in the phrase syndrome here right and this is something I told you that injury to the peroted surgery sensor loss and shaving area pered is shaving that that's how the question was asked here so all the points that is written in front of you they're all asked as separate questions runs with exter external jugular vein supplies the lobul of the ear supplies the angle of mandible perotid region phrase syndrome sensory loss in the shaving area question exam already or sub answer that is great oric you can see how commonly this question is asked here so that's a nerve which is basically present in the roof here the another important structure that I need to tell you in the posterior triangle is the spinal accessory nerve and I wanted to look at the screen that how the nerve is running guys nerve actually come from anterior to posterior look at that if you look at the nerve running from anterior to posterior that's a spinal accessory nerve so spinal accessory nerve basically supplies the sternoclto mastoid First first it supplies tenor mastoid then it supplies trapezius muscle and that's the catch because spinal accessory nerve is running in the neck quite superficially in the posterior triangle So it is it is kind of like it it gets injured in this way If the spinal accessory nerve it runs between the investing layer and prevertebral layer It is running between the investing and prevertible That's why it's very superficially placed If the spinal access nerve is injured in the posterior triangle the problem is the trapezius muscle will get affected but not sternocltomastoid Sternoclto mastoid muscle will be spared Sternoclto supply muscle is already supplied by the nerve and then it enters into this triangle So if the nerve is injured in the posterior triangle always remember that patient will not have any loss to the sternoclomomastoid We'll only have the function of trapezius muscle affected And what are the functions of trapezius mus which are affected The patient will have difficulty in shrugging of shoulder difficulty in retraction of scapula difficulty in overhead abduction and to some level it will be bringing of scapula also but mainly the trapeze is affected and that will cause all these guys It will cause difficulty in shrugging difficulty in retraction of scapula difficulty in overhead abduction So only trapezius fun features functions are affected but not sternoccletomastro muscle will be spared So that is in the post there is there's there are too many things in posterior triangle guys we have we have trunks of brachal plexes subclavian vessels but again as I said my job is to kind of filter the information give it to you from the exam point of view when the question is asked on the posterior triangle I can vouch for it their favorite favorite question to ask is either great oricular nerve mainly great orical nerve in fact I would say or the question on the spinal accessory nerve and this has been repeated like from last 10 15 years they've been asking questions on these two nerves repeatedly over and over Okay Yeah Okay Again cranial fora guys I I believe that you people have read about the cranial fossa You read about the different forammen here But again I have to I need to focus on the most important forina in this picture and the two forin which is again asked in the recent time as well One of them is the forammen lesserum Now if you look carefully this forin leum is not a foramin in any bone It is a space left between the bones Yellow color bone there is a sphenoid bone The green colon is a pitrus temporal The blue one is occipital bone So different bones are surrounding this here So this foramin here is called as a forman lesserum And this forman leerum is surrounded by look at the multiple bone We have spinoid bone greater ring of spoid body of spinoid We have pus temporal apex of pitus temporal and we have a occipital bone bas basal part of oxal So simply name the name name of the bone only sphenoid temporal pitus temporal in fact and occipital bone that is the one which is surrounding this the forin lesser is an interesting foramin because there are some structures which are just traversing the forin lesson they are just traversing it like like passing through and through and some structures are coming from somewhere else and just running through it here so they're not the true content so in the foramin lesson guys there are two types of content now when I say traversing for lesson the the major content of famin so we have Some you know menial branches of ascending fangial artery a artery which is supplying the durometer and some emissary vein is there The structures which sounds not very important are the actual main content of the forom and lesserum Apart from that we have greater petroal nerve internal coroted artery lesser petroal nerve sympathetic plexus all these structures are present inside the forominum but they're just filling it up They fills up they are not the actual if this is for less something passing through for less is something which is traversing it but structure side like this and then goes into foramin lesson that's just filling it up it's not the main content overall these are the contents of foram lesserum but if they ask you the question like what structures are traversing for lessum then you only have to go with this artery and the misery vein and not all these Okay The another important feramin is the jugular forammen guys Now this jugular forammen again is present between two bones Look at the green and blue over there We have petrus temporal and occipital bone So jugular foramin is also present between the two bone that is occipital bone and petrus temporal Jugular foramin the most anterior if if I just take it out the most anterior and the posterior part of jugular foramin is having the two sinuses which together will give rise to internal jugular vein So we have a sinus called as inferior petroal sinus and then we have a sigmoid sinus that is inferior petroan and sigmoid sinus and both these sinus comes out of jugular foramin and immediately below the jugular forammen they join to each other to form internal jugular vein So a question be that these are the two formative tributaries of internal jugular vein When these two sinus unite together they give rise to internal jugular vein The nerves which are present between in the forum and le in the sequence from anterior to posterior we have 9th 10th and 11th nerve We have 9th 10th and 11th nerve And in the ninth 10th and 11th nerve one and and some arteries some menial branches of ascending fangial arteries are also they're not very important So the important thing is guys 10th and 11th nerve can you see a dotted line present around them and ninth is having a separate dotted line over there Look at that circle moving circle over there That's a that was a question asked here Ninth nerve ninth nerve is the one which is having a separate passes through jugular foram There is a separate passes for the ninth nerve to pass through it because there is a separate dural sheath for it 11th nerve and 10th nerve they have a common dural shoot because 10th 11th nerve they obviously both going to join together and they will form the vego accessory complex So that's why 10th and 11th nerve they have the same same what do you say uh dural sheath and ninth nerve is the one which is having a separate dual sheath is there nth nerve is having a separate dual sheath here that that's why the ninth question was asked the question was something like this that which content present in jugler foramin is having a separate passage jugler for maybe but still separate passage and that is a ninth nerve over there right so these are the two most important forin that that I I you should know about that is the inf that is the ninth nerve is the structure which is passing separately through it Now this picture guys if you're looking at a picture like this where you are looking at the cranial fossa and in this cranial fossa if you if if you look at that box over there it is showing you some cranial loves inside you I would I I believe that this question probably will not be asked in the neat exam it's more oft type of question when they can give you a picture of the cranial fossa but with the durometry intact If the durometry is intact it's a little difficult to identify the nerves So we got to go with certain hints over there Like if you look at this in the anterior cranial fossa you can see there's a projection coming from anterior cranial fossa toward the posterior side toward the middle cranal fossa That is called as the anterior kenoid process If you see a nerve is this picture cavendary sinus will be somewhere here This is where the cavendary sinus will like it's it's just roughly that is that is the place of the cavendary sinus there Now this nerve over there it's a optic nerve that is nerve that is to optic nerve is there optic canal is present just medal to the antior anterior cleoid process immediately that is a optic canal so optic nerve is there the nerves which we already discussed present in the lateral wall of cavend is third nerve fourth nerve look at the thin nerve over there fourth nerve and we have the fifth nerve now I cannot see the parts of fifth nerve I can just see the trunk of the fifth nerve over there so look at the fourth nerve especially let me enlarge this for you guys look at the third nerve there and this thin thread-l like nerve the thinnest cranial nerve the fourth nerve and the fifth nerve these These nerves are present more toward the lateral side in the lateral ball of cavender sinus The only nerve which entered the cavvernous sinus was a sixth nerve abduc nerve and the reason it entered the cavender sinus because it is coming from posterior side and that is one of the nerve asked in the exam This is the abdus nerve Don't look for the abdus nerve on the lateral side Look at behind the cavender sinus region That's a six nerve guys That abduc nerve or six nerve is there Right That's the only nerve that you see on this clus Clus is the slope That is a six nerve abduc in the posterior cranial fossa this is where we have internal aostic miatus this is where we have jugular forammen and further below we have this hypoglossal canal and that's how you can make out the content if it is a internal eostic miatus region there that means it is going to give passes to seventh and seventh and eighth nerve if this is a jugular forammen we just saw it is going to give rise to 9th 11th nerve and further below you can see some rootlets of the hypoglossal nerve are present there so in the sequence you'll find them in The posterior canal fossa you may see a tough nerve above then further below then further below that is we have the sixth and seventh nerve uh seventh and eighth nerve I'm sorry that is from internal aostic mus 9th and 11th nerve from the jugular forin and hypoglossal nerve rootlets can also be seen that is present over there so that's how you're going to identify the nerve if the durometer is intact look for the anterior kenoid process this cleoid process the nerve medial to the kenoid process is optic nerve the nerves in the lateral wall of cavanas 3 four and five nerve the nerve which is present behind the cavina sinus through the clavus 6 nerve and then in the posterior canal truss look for internal aostic mus jugular feramin and the hypoglossal canal I mean in the sequence you can find out the nerves are running in there if the durometer is intact okay guys moving on now I'm sure that the moment you look at This picture we all know that this how many times this question is being asked and they are still not stopping Tyrion tyrion is this point obviously which is on the this H-shaped suture is on tyrion on the side of the skull When I say tyrion guys the four bones which are contributing to tyrion are we have this that is a frontal bone of course that's a frontal bone contributing to tyrion we got this parietital bone that's a easy one and the next two bone you need to be very specific here this is the we have the squamas part of temporal bone first of all it's not the petus part the squamas part of temporal bone and the greater wing of the spinoid here so please make sure that for the temporal bone and the spinoid bone remember what part is that that's a squamas temporal and we have the greater wing of the spinoid okay tion is important And here the thinnest part of the skull bone actually easily fractured also any blow to the skull on the side the tyrion can get fractured and there are many structure present inside which can get involved So what are the structures which are lying deep to the tion Well we all know guys if this is a skull and you can see the brain is shown like deep to it here now and that is somewhere the trion is present like just roughly middle managel artery we all know that middle managel arter is having two division it's the anterior division of middle managel arter which will be seen over there So look relation may can we add see superficial temporal vessel this is a very recent question generally we think about the deeper relation there's one relation outside also superficial temporal vessels are there now if I go inside the tion you will see the anterior division of middle menangel artery this sulcus here is a sylvian sulcus or sylvvian fissle middle cerebral artery passes through it if I go further more deep then I'll see middle cereal artery or middle cereal vessels are there this fissure this where the middle cereal artery is present is called as sylvian fissure Insula you know that the sylvian fissure if if you open the sylvian sulcus or lateral sulcus hidden lo of the brain can be seen So insula and if a person on the left left side I mean this this is the right side here on the left side the deep to the tyrion because inferior frontal gyus is also have broka's area So even broka area is in the relation main relation is anterior division of middle managel arter No doubt about that middle managel arter is a main relation to the tion But question we should know all the relation for the Tion here So superficial temporal vessels are outside middle menal artery You go further inside you'll see middle cerebal artery Further inside is silven fisher More inside is insula and even the brokas area on the left side is also in relation to the tyrion So all these structures all these areas can be can be approached taking this the tyrion route Yeah Well this I'm sure that you must have discussed this with Dr Rojat in detail about the extra dural hemorrhage Any rup any fracture of the stion can lead to the rupture of the anterior division of middle managial artery causing the extra dural hemorrhage So followed by this some some of the topic of head and neck again we come back to some of the some of the topics from the hisystologology and this is something which I have taken from my own will because in the entire g slide I'm not expecting you to sit down and read every slide of git I feel this is important because a slide of a deodorum what makes a deodorum slide important guys do diodum is one slide in which you will see these glands vi you will see in deod vi which are having these goblet cells and colonar epithelium and microbilli will be there that you will see in the gigum also also to I say though I don't think that you will be able to differentiate between diodnum junum and that's not easy what makes the diodum very important and very specific is the presence of this bruner's gland now look at this bruner's gland this mucos they are present in sub mucosa generally glands mucosa subuc intestinal glands sub mucosa subucal glands the two slides which are having the glands in sub mucosa one is esophagus esophagial glands are also in sub mucosa mucosal glands are there and even bruner gland in the diodum are also in the submucle So that's the main reason I want to just show you this picture here You're looking at the vi the moment you look at the vi obviously g slide git slide is it is it is it junum is it diodum diodum is easy to identify diodum you're looking at the glands which are present in the sub mucosa guys can you see the muscularis mucosa over there that is a muscularis mucosa there and if this is the muscularis mucosa deep to that is what sub mucosa and you have the bruner's gland in sub mucosa had it been the slide of the stomach or the slide of the jigum or slide of the other part of the intestine then you will see the intestinal gland and present only in the mucosa not in the sub mucosa Thyroid follicle very simple slide but because it is asked on the exam so I I have to give it to you guys that that is a thyroid follicles you're looking at when you look at the thyroid follicle you can clearly see these the cubuidal cells or colonar cells could be there cubidal to colonar cells can be seen cuboidal is a better answer choose what is simple cubital is a better answer that the thyroid follicles are lined with then inside you can see the colloid and these colloid is having a serrated borders are there guys that it's a active thyroid gland that looking at and we have a serrated border of the of this of this colloid and What is also to be noted that between these these thyroid follicle we have these cells look at these cells guys in between here these are the parapholicular cells the same parapholicular cells which are derived from the the neural crest cells which are migrating into the fangial arteries into ultimal body So these parapholic cells the large cells and they are poorly staining So basically it's it's pretty easy to identify if you're looking at thyroid follicles and thyroid So these are larger cells the big nucleus is there and they are basically poorly stained compared to the follicular cells they are the the parapholicular cells will be there right so the thyroid follicle slide is there now one slide which is not asked in the recent time but you know sometime we have to kind of anticipate certain thing and and this is what I anticipate guys this is not the slide to which is asked in the recent recent time it's it's a never in the image based question yet but I feel that adino hypopis anterior pituitary slide are important anterior pitutary slide is important because the staining are very very clear and you can see the three types of stain over there You can see acidophils you can see basopils and you can even see chromophobes the cells which are poorly stained Right Okay So if I say in the anti adinophis if I talk about the acidophils you know acidophils I mean you read this all in physiology and pathology and and medicine very well So I don't have to go into that See this about the acidophils they stay in red in color Somatroes and electroes The question could be they might give you a slide like this and they will ask you about the the the hormone which is being secreted by those cells here The acidophils are the somatroes and electroes If it is a blue stained cell you can see the stained blue basopil cells We have thyotropes gonatroes and corticotroes are there That is from the basopils And then look at the this especially I'm just putting this arrow over there It is neither acidophil nor basopil It's a chromophobe Pale cells are there Maybe inactive or in transition We don't know much about the chromophobe cells here but the chromophobes are also to be seen over there Now again this is a slide which I have given to you because looking at their in the recent time they have given some gland slides and this is the gland they have never given and this could be a good question to formulate also you know self mark maybe acidophil and they will ask okay which hormone is secreted from this so they will give TSH ac GH or any other you have to go with the GH over there it's a somat which is coming uh somatro cells are there which are acidophils right so identify the acidophil basopils and chromophobes and I hope that you already read about this in endocrine in in more detail I I'll share this PDF Don't worry about the PDF It's all yours Just Just immediately after the slide the first thing I'm going to do is I'm going to send this slide uh to the to the moderator and he will he will share the slides with you with you all Don't worry about that Ch sir let's move on to the next major unit that is neuroanatomy Now neuro guys in the neuro anatomy uh I mean again as I said we have to just filter out the information and look at the major part from where usually the questions are being asked although I believe that neuro is something that if you would have read I mean INI is too close but for the neat exam I would say that if you have not read neuronatomy investing one day for the neuronatomy is not bad I mean and you're just relying on the one shot or like just only what is important in this I would say neuro If you read this in more detail that will be beneficial not only in the NT part from the other other other medicine part and physiology part as well So neurom if you whatever time you'll invest looking at that one exam is very close and then then we have a neat exam we have some some some more time in between So you know I would say that it's a time it's it's topic which is worth investing time and though we'll be talking about some important topics in there like first of all like the squeeze of the entire spinal cord and that is brown syndrome If you know the brown cich squid syndrome that means you know the tract say guys in the spinal cord we know that we have dorsal column tract if I just just very quickly clarify to you let's say this patient is having a brown squid syndrome whichever level the brown squid syndrome is present whatever level there is ipsilateral loss of all sensory modality at the level of vision just be level injury let's say there is a injury at the level of T6 so at the level of T6 every single modality is gone pain temperature touch pressure crude touch or fine touch or vibration or stero everything will be gone at the level of lesion So ipsyateral loss of all sensation only at the at the level at the level of lesion there will be just just hold on for this one There will be ipsilateral loss of vibratory sensation and position sense because dorsal column tract runs on the same side only guys Dorsal column tract run on the same side If the dorsal column tract is running on the same side so injury will have a ipsilateral effect and dorsal column tract is responsible for this vibration and the position propreception contraateral loss of pain and temperature below the level of lesion Why Because spiny tract they cross over and because spinothermic tract will cross over and will go above So any injury to the spinothermic tract left side spinic tract injured to right side pain and temperature So contrateral loss of pain and temperature below the level of leion So exactly just level exactly at the level of lesion everything is gone But if I talk about the bigger picture below the level of lesion first of all you will see ipsilateral loss of vibration ipsilateral loss of position sense because of dorsal column tract Contrateral loss of pain and temperature because of what tract spinic tract especially mainly because of lateral spinalic tract involvement And something which is very important to understand paralysis guys let's say this is a spinal cord here the rough section of spinal cord we all know that c lateral cortical spinal tract will decisate that's how the lateral cortical spinal tract will decisate in middle oblonga it will decisate in the middle oblonga and these fibers will now come into the spinal cord that is the upper motor neuron and from spinal cord the lower motor neurons will come out like that's a lower motor neurons all coming out there these are all lower motor neuron let's say this patient is having a brown squid syndrome at this particular level look at this flashing light over there this is where the brown sequid syndrome is there No just level pain at whatever level the brown sequid syndrome has occurred at that particular level lower motor neuron are injured and that's why this patient will have a ipssilateral flaccid paralysis at the level of lesion ipsilateral flaccid paralysis at the level of lesion because lower motor neuron is injured but rest of the lower motor neurons are fine they're working no problem but their upper motor neuron is affected here or upper motor neuron injury to there will be paralysis below below the level of lesion Ipsyateral paralysis below the level of lesion that confines the entire brown squid syndrome A patient with a brown squid syndrome will have a ipssilateral loss of position sense ipsilateral loss of the vibratory sense contrlateral loss of pain and temperature IPSL flaccid paralysis leion and ipsilateral we have the paralysis below the level of leion Yeah below the level of leion So you have to the question about the brown secret syndrome is all about ipsilateral and contrlateral If you people have read about the spinelic tract dorsal column tract spinal cerebellar tract it's not a problem but presuming that if you haven't read them or if you forgot about these tracks at least remember these feature that which one is ipsil which one is contrateral The simple one simple way is pain and temperature contrateral Just keep that pain and temperature is contrateral Everything is ipsy ipsy ipsy ipsy ipsy and you still will be able to mark the right answer in that Okay there's a picture showing the vententral aspect of the brain stem Now in the vententral aspect of the brain stem guys uh you're looking at this this this area is a midbrain area Look at this This is a midbrain area that is pawns here and that is medongata Now if you look at the midbrain area the this space between the two pedunkals of the midbrain that is that is crust cerebra It is also called a cerebral podunkcle We have a interpreular fossa in between and the nerve coming out from interpunular force is the third nerve Look at the third nerve from interpunular fossa Fourth is the only cranial nerve which is coming from the dorsal aspect here The nerve which is coming from posterior side The dorsal aspect of brain stem that is a fourth nerve The tlear nerve Pawns is huge guys Pawn pawns is huge But the only nerve that you see emerging from the vententral surface of pawns is the thickest cranial nerve and that is a trigeminal nerve Trial is the only cranial nerve emerging from the vententral surface of the pawns because the nerve sixth seventh and eighth are coming from ponttoidillary junction Okay The sixth nerve then we have seventh nerve both both are seventh It's a mixed nerve So part of and then we wait now sixth seventh and eighth nerve coming from ponttoillary junction So not from the pawns pawn to middleary junction they leave the brain stem from ponttoillary junction from medial to lateral 6th 7th 8th in the middle oblong are the two major elevation that you have one elevation here this is pyramid guys that's pyramid and that is olive pno pyramid and olive if you look at the nerve which are lateral to the olive olives lateral present poster lateral to olive we have 9 10th 11th nerve 9th 10th 11th nerve that emerges lateral to olive and 12th is the only nerve which is coming out between pyramid and olive emergence of the cranial nerve is a very very important When you're looking at the vententral aspect of the brain stem to minim how cranial nerves are coming out Third nerve from interpular fossa Fourth nerve is the only nerve coming from dorsal aspect of brain stem Then we have fifth nerve the only nerve emerging from the vententral surface of pawns Sixth seventh and eighth nerve from what junction Pontto medillary junction 9th 10th and 11th nerve they are coming from lateral or poster lateral to olive And 12th nerve hypoglossal nerve is emerging between pyram and olive perimeter that is 10th Okay Then the dorsal aspect of the brain stem guys We're looking at the brain stem from the front Let's turn it around guys When you look at the dorsal aspect of the brain stem the first thing you'll notice above is a superior colliculus inferior choleiculus So we have two superior choleiculus and two inferior chaulus And all the chiculus together are called as a corpora quadriggerina The four gemlike structures we call them corpora quadrigina Just below the inferior colliculus you can see the only cranial nerve which is coming from dorsal aspect of the brain stem What nerve was that guys That's a fourth nerve Look at the fourth nerve over there So when you're looking at the dorsal surface of the brain stem and there is a fourth nerve emerging from there Now in the flow of fourth ventricle there are many structures present over there But I'll tell you if it is a cadaboric image based question they are going to ask you this that is facial calulus That facial collus what is facial caluculus Facial chuculus is the sixth nucleus present is deep to it That is facial cauliflus and the facial nerve is winding around it Internal genome of the facial nerve when six nucleus is present in the pawns and you will see facial nerve winds around the six nucleus and emerges out and that is called as a facial cauliflus guys Facial colliculus is there just below facial calulus we have hypoglossal triangle veagal triangle but I tell you honestly in the image based cateoric picture I'm very sure that they will not going to ask you where is hypoglossal triangle veagal triangle it's not that easy to identify them facial collus very easily is easily appreciated here we do have vesticular triangle also now one question here is that which cranial nerves are seen in the floor of fourth ventricle facial collus deep consonant nucleus six nucleuses deep to facial Colluculus vestibular is eighth hypoglossal is 12th and trigonosense So the nerve which are present deep to the in the floor of fourth ventricle we have 6 8 10 and 12 6 8 10 and 12 But what makes facial collus so important Facial chiculus may we have this abducent nucleus which is surrounded by the seventh nerve So any injury to the facial colliculus the first structure to get involved is a facial nerve Nerve nucleus So if the question says there is a injury to facial colliculus or there is a injury to the structure producing facial colliculus always think about injury to facial nerve because nerve is present around the nucleus So the facial nerve will get affected first and that's why the muscle of facial expression might be showing you the feature in that case Sixth nucleus may or may not get affected because it is present deep to the nerve here So that's the facial caulifus Look at the guys This is the picture showing here Look at what it shows You can see facial nerve is there and that is winding around the sixth nucleus and coming out here So any injury to facial collic on the dorsal side if there is any injury to the facial collic from the dorsal side the facial nerve will get affected right that's a facial actor so the question if the question says which cranial of nuclei nuclei which cranial of nuclei present in the floral fourth ventricle so we have 6 8 10 and 12 nuclei but obviously the injury to facial colus I told you abducent nucleus surrounded by the lower motor of facial nerve any injury to this facial facial collus there will be lower motor neuron leion of facial facial nerve injury is the first thing you have to think about the bar because I know that they will keep on twisting this question over and over again but do not deviate from your answer unless the examiner says there is a injury to the nucleus present deep to the facial collus never go with sixth as an answer injury to facial colliculus injury to the structure producing facial collus injury to this bump that you see in the floral fourth ventricle It's mainly the injury to the facial nerve What's cereal Don't worry Okay Yeah So central section guys three sections of brain immensely important Now look at this green highlighted area this this flickering area the green area that's a third ventricle So when you see the statical section thirdle in the picture like this it's very important for you to identify the structure the question could be very simple the question could be about connections question could be about something else but if you don't identify the structure then you will not be able to answer it if you look at the third ventricle the roof of the third ventricle it is made of this a white matter bundle which I'll talk about separately also is called as fornex the forex the body of fornics is there and just below the forex there we have a koid plexus so The body of forex and coroid plexus are present there that is forming the roof of the third ventricle anterior wall of third ventricle is by let let me go to the posterior according to this powerpoint posterior side of the ventricle we have a pineal gland so what I was saying that it it's a penal gland there above the penal gland and below the penal gland do commission commissioner we have a habinular commissioner above and we have a commissioner which is present below is called as a posterior commissioner and just below the posterior commissioner I hope you can even appreciate this aqueduct of silver there look at that duct over there which is leading into the fourth ventricle that is aqueduct of service So these four structures are forming the posterior wall of third ventricle in the sequence Nowadays examiner is very interested in asking this question arrange them in the sequence and that in the sequence So healer commissioner penal gland posterior commissioner aqueduct the four structures forming the posterior wall of the third ventricle Anterior wall of third ventricle is by the commission another small commission that is called as anterior commissioner and the laminina terminalis Lamina terminalis is important embryologically also because lamina terminalis indicates the closure of the cranial neuropore The neural tube guys the neural tube to it forms a lamina terminal is cranial neuropore when it closes cranial neuropore closes on day 25 On the 25th day when the cranial neuropore is closed eventually brain can the structure which represents that closure of the cranial neuropore is this laminina terminalis Laminina terminalis is the cranial most end of the neural tube closing closing of the cranial neuropore Yeah And then comes the floor I'll tell you something interesting here The floor of the third ventricle has something to do with the vententral aspect of the brain stem Just just give me one second if I if my im may just very quickly take you back to this picture Yeah look at that guys Have a look at this here If you look at the vententral aspect of the brain stem can you see opticma there Just look at the circle there Opticasma that is infundum of pituitary This there we have the mammalary bodies and then we have posterior perforating substance Look at these structures in the sequence here Inficiasma there is infundibulum of pituitary Then we have the two melary bodies to be seen and that's a posterior perforating substance When you see the brain stem from the front these four structures are present like this right That they're forming the interpunular fossa But when you take a section the same four structures are forming the floor of third ventricle You can see that Let me just take you back to the that point here We've already done till look at that Can you see optic asthma first Then we have infundibulum Then we have mammalary body and then we have posterior perverting substance Some part of the midbrain also segment of the midbrain This midbrain tementum is also there But mainly these are structures which are sorry these are structures which are forming the floor of the third ventricle Right And in the recent time there was a question asked on the melary body Mealary body was given that and the question was melary body projects into which nuclei It projects into the anterioric nuclei The fibers of the melary body that projects into the anterioric nuclei That was asked here So in the question in the picture like this it's it's very important to identify the suture identify where is forex where is corid plexus where is pineal gland If you can't identify the structures the question doesn't make any sense to you So in the three sections of brain sittietal transverse coronal identification of the structure is very important Cital section it gives you about the third ventricle the boundaries of the third ventricle to be seen But Pepe circuit physiology topic pepe circuit is like hippoc campus hippoc campus say we have starting of this you know the phonics if I may show it to you I'll come to that in fact I I'll tell you a little about the pepe circuit but though it is more of physiology topic here though this picture I have to give it to you because if the arrow was placed like like this here one of the arrow is placed just behind the midbrain the lower part that's midbrain here that is a pawns so behind the midbrain guys we know the only nerve which is emerging from the dorsal aspect of the brain stem That is the fourth nerve The but make sure that the you're looking at the arrow placed somewhere behind the midbrain So that is a fourth nerve The second arrow is placed in the floor of fourth ventricle And we just discussed that it's a seventh nerve making a facial collus and coming out like this So it's a facial nerve Facial nerves nucleus is sixth over there The facial nerve is basically emerging like this making a facial collus So if the arrow is placed somewhere behind the midbrain like the upper arrow then fourth nerve is the answer If the arrow is placed somewhere in the floor of the fourth ventricle then seventh nerve fiber can be seen in that region here So that's the two question what could be asked from this in the dorsal aspect of the brain stem This section over there is a coronal section This section here is is a is a coronal u voki prilarani anatomy makes me cry Yeah Okay I know that you'll be asking you are asking that when the class is going to get over uh coronal section guys in the coronal section see what you're going to see that this time this here is the sorry that's the lateral ventricle and that's a third ventricle third ventricle already I want to look at this way if you already done with third ventricle now we know the lateral border with third ventricle is by thealamus this isalamus roof of the third ventricle when we saw that roof of third ventricle is by choroid plexus and phonics Now this is the choid plexus and this over there is a forex We already saw that in the sital section the roof of third ventricle is by phon for phonics and corid plexus The only difference is this time the this time the view is different So when you look at the coronal section the roof of the lateral ventricle is by corpus colosum The that is internal capsule internal capsule If I go more outside guys then the internal capsule once the internal capsule reaches above you can see the fibers are rading in all direction that is called as a coronary radita This internal capsule that is coronary radiator is there we go further more outside then we have this lentififor nucleus and outside the lentiform nucleus we have this hidden lo called as insula Insular cortex is there Insula was one of the first image based question asked in the anatomy guys 2014 question 2014 they gave this coronal section and their question was that where is insula in this picture the insula is it's a hidden lobe unless when you open the lateral culcus then only you're able to appreciate this insula in that way that's a lentiform nucleus I already told you now from the third ventricle point from the lateral ventricle point of view the roof of the lateral ventricle is corpus colosum medial wall is by a thin septum called a septum pelicidum that is septum pelocum and then everything is the floor guys the lateral ventle there is a roof there is a medial wall and then we have a sloping floor you put a floor here this whole thing is a floor only this this whole thing is a floor of the lateral ventricle where we have what Where we have cordate nucleus where we have thalamalamus and we have the phonics and the coroid plexus The phonics and corid plexus just look at up close So you're looking at the septum pelicidum forming the medial wall and the floor is formed by this the cordate nucleus There is a forex there is a coroid plexus which is present in the roof of third ventricle and thalamus is there The a basic identification of these structures are very important because the question again the question could be asked on anything but you got to identify septum hair where is cordate nucleus how exactly the forex is going to look like in the coronal section So just a basic identification is is definitely to be done This is a picture where I can tell you a little about this uh you know the pepe circuit also but I don't want to go into too much of detail of that guys What you see over there that the blue color fiber over there is a forex The forex is something which you cannot see in one section very clearly It's very obliquely placed fibers here Phonx is a white matter bundle which is basically originates in hypoc campus That was a question asked in the exam It's one of the INA question only Phonx is a white matter bundle The fibers of the fornics starts where In the hypoc They originate in hypoc campus and they come downward and forward and that terminates in memorary body The termination of the phonics in the memorary body Forex is a type of a projection fiber Association fiber Forex up Forex is an association fiber also It is a commercial fiber also It's a projection fiber also And the the purpose of fornix is to originate from hypoc campus and terminates into the melary body Mealary body then projects into the anterioric nuclei Antiththalmic nuclei projects into singulate gyus and singulate gyas via singulum again projects into the hippocampus And that is the whole pepe circuit Pepe circuit can what I'm saying is that there is hippocampus hippocampus viaex viaex hypoc campus is projecting into what body mealary body melary body projects into the phalomic nuclei that is antalic nuclei anteriorthalmic nuclei projects and it projects into the singulate gyus of the brain which is present on me singulate gyus singulate gyus via A white matter bundle called a singulum It projects back into the hippoc campus You put a circuit pepe circuit guys That's a pepe circuit of the emotional integration That hypoc campus projects the fire forex fiber into mammalary body Melary body goes into the phalamus anti-thalmic nuclei Antiomic nuclei send the uh you know the what do you say radiations into the singulate gyus Singulate garus projects back into the hippoc campus That's the the pepis circuit over there bad insula Okay The third and the final section in the sectional atom of the brain is a transverse section Guys when you take a transverse section of the brain now again the same thing Can you see that white matter bundle This this is somewhere we have the genome of the corpus colossum If just imagine if the corpus colossum is somewhere here that's a gene of the corpus colossum And here we have the spleenium of the corpus colossum The fibers of the genome of the corpus colossum are going forward and that is called as a forceps major fiber So that they come forward and connect the frontal lobe that is a forces major fiber From the spleenium of corpus colossum look at the fibers which are running backward These are called as a forceps major fiber and forces major fibers are such a thick fibers They produce the elevation in the posterior horn of the lateral ventricle called as a bulb of posterior horn Look at that bulge over there Can can you see that elevation guys This elevation which is present in the in the medial wall of posterior horn in the posterior horn of lateral ventric elevation that is called as bulb of posterior horn and this bulb of posterior horn is because of force major It's the forceps major fiber which are responsible of producing this elevation More lateral to this uh posterior horn of lateral ventricle we have another white matter bundle which is called as a tpatum Forceps minor forceps major and tpatum are nothing but the different fibers of corpus colosum only Your corpus colossum key fibers which are running in the different directions to connect the frontal lobe and occipital lobe like forces major connects the frontal lobe and tpatum and forces major they mainly connecting the occipital lobe and lower part of temporal lobe also What else is seen in this section In this section I can again see internal capsule in between that is internal capsule Look at this L-shaped white metal that is internal capsule and this internal capsule is surrounded by on the medial side by the cordate nucleus and phalamus and on the lateral side by the lentiforififor nucleus and we have insula for the laterally placed here that is the same relation guys the one relation that you see in the coronal section you can see in the transverse section also the if I if I just try to compare u thank you guys thank you thank you so much if if you try to compare this picture with the MRI image though look at this MRI image here and if I try to compare this MRI image with this image what I what I'm doing is let me superimpose that MRI image on this and you will see a magic look at that well that's that's very satisfying right if you look at this picture now in this image I can see both cateoric image and MRI image how to identify the structure the same labelings are there look at the forces minor how it how the forces minor look like in the MRI image And in the cadoric image how the corded nucleus looks like in the in the in the cadoric image in the MR image in the cador image that is a lentiform nucleus lentifor that is thealamus here this is thealamus here that's internal capsule look at that this is internal capsule which is shown over there that is a forces major that is a forces major so you can kind of most of the structures you can compare on both the side so even if they give you a radiological image or even if they give you a category image I I hope that you'll be able to easily be able to compare them and you can still you'll be able to identify the structures in Thank you guys Your messages are one which are which are making me stay awake at 2:00 a.m It's we exactly it's so 1 it's it's almost 2:00 a.m now but I'm not sleepy at all Okay Cerebellar cortex guys Cerebellar cortex very easy topic but you get a lot of questions from there When you look at the cerebellar cortex the cortex part guys Cortex You can divide the cereal into cortex and the white matter The cerebellar cortex having three layers As you can see there is a molecular layer Look at that circle over there Which is having two types of cell Basket cells delayed cells We have a perking layer We have what Perking cells And we have a granular layer which is having the two types of granular cells and gi cells So total there are three type three layers in the cereal cortex We have molecular layer We got a perking layer and we got a granular layer Molecular perking granular layer And total five types of cells are present there Basket stilate perkingi granulgi basket cells stilate cells perking cells and golgi cells they are inhibitory cells inhibitory cells cereal cortex it is like it is it is you're so negative it's like the cerebral cortex bolite you're so negative you all negative cells are there inhibitory inhibitory inhibitory inhibitory cells are there the only excitatory cell which we have in the cellular cortex is a granle cell so it's a granle cell which is excitatory in nature sub inhibitory Okay And that is why cerebellar cortex is the largest collection of inhibitor neuron in entire central nervous system In the whole central nervous system inhibited neuron There's the biggest collection of inhibit neuron in the in the CNS in the CNS but the outermost layer is is the molecular molecular is outermost then we have perki then we have granular guys collectively thank you for all the messages that you're sending here I would love to hear more of more of these but but after the class so I would love to read these messages but you know let me just stay focused on on on on the slides and then I would love to read everything that you were writing Okay Now the out of all the cell that looking at a perk cell only perk this this is a perking cell that's the only cell which actually comes out of the cortex All other cells are having internal connection The only cell which actually leaves the cortex and comes out in the white matter is perking cell to eph from the cortex Okay What about aphrant fibers that the fibers which are entering the cerebilum There are two types of aphrrent fiber We have climbing fibers and mossy fibers Look I say climbing fiber and mossy fiber Now look at the arrow first Climbing fiber The orange colored fiber which are shown as climbing fiber The reason we call them climbing fiber because they can climb to the topmost layer and they're directly sinacing with what Perking cells That's why we call them climbing fiber Second type we have got mossy fibers Mossy fibers are those which will come inside But mossy fibers are going to connect to the perking cells via these cells And what these cells are these are granule cells Bag granle cells are the only excitatory cell remember And the reason they are excitatory cell because it's the responsibility of the granle cell the mossy fiber connect with the perking fibers here So we have two types of aphrant coming into cerebellum The climbing fibers are the one which climbs directly to the to the molecular layer and and and and the perk this what do you say Uh the mossy fibers are the one which are going to use the granule cell granul use and then granul will connect them to the to the molecular layer The question is which fibers are climbing which are mossy or easil and paroly cerebellar the track olivery olivery word in the name of the track that is climbing fiber The olivery olivo cerebellar paroly these are climbing fiber rest everything is mossy Anything else coming into the cerebellum sub mossify fiber whatever it is guys dorsal spino cerebellar reticular cerebellar pontto cerebellar this and that whatever comes inside the cerebellum everything is a mossy fiber except olivery word olivery word is written in the tract olivo cerebellar paraolio cerebellar superior oliver cerebellar all these olivio cerebellar pathways are climbing rest everything else is mossy fiber so majority of the fibers are mossy fibers Right So this is about the cerebellar cortex Now if I just show you the hisys histoological picture of that that is a picture that they love to give and especially more in the more wide that that is the area if I focus over there that's the perking cell and I told you what about the perking cell guys perk aa cell perking cell is the only cell which basically sends the epherent from the cortex but when the perka cells epherent come out of the cortex they come into the white matter and in the white matter we have what deep cerebellar nuclei the ephrent from cerebellum will come from deep cerebell nuclei perking only ephrent from cortex But ephrent from cerebilum will come from deep cerevil nuclei This this arrow should not be there in between Let me just let's rectify this This arrow should not be there This is one information Perking cells are forming the ephrine from the cortex and the ephrent from cerebellum will be coming from where Deep cerebellar nucleus Especially the dentate nucleus Dentate nucleus is the main nucleus which is present in the white matter that sends the the fiber outside The one of the one of the most commonly asked question in the cerebellum is about the cerebellar predunals Now there are three cerebellar peduns guys if just try to get an orientation to the picture You're looking at cerebrum there That's cerebrum here This triangle is thealamus Let's say this is thealamus there and looking at three part of the brain stem Midbrain pawns and middle oblong You can see midbrain is connected to cerebellum by this yellow color peduncle Superior pedunkcle This is middle podunkcle There is inferior pedunk These are cerebellar peduncle First of all do not confuse the cerebellar and cerebral podunka The cerebellar pedunk one easy way middle cerebellar peduncle this tract here is a corticospinal tract The one copy guys when when the cortical spinal tract comes down one copy of corticospinal tract goes into cerebellum and that copy of corticospinal tract is called as a cortico pontto cerebellar tract and that is entering the cerebellum through which punk to the middle cerebellar podunka that is called as a cortico pontto cerebellar tract and cortico pontto cerebellar tract is the only major tract that you see passing through middle pedunk middle cerebellar peduncle middle cerebellar peduncle purely aphrent that means middle cerebellar peduncle is allowing the tract only to come inside it's purely aphrent biggest pedunk or purely aphrent PM superior cerebella peduncle is giving passage to one tract called as a ventral spinal cerebell the ventral spinal cerebella tract from superior peduncle and the eph which are going from dentate nucleus the feedback which is going from dentate nucleus the feedback from cerebellum going from what nucleus dentate that's a dentate nucleus over there guys that's a dentate nucleus so these tracts are called as denttothalmic and dent ruboththalmic going through the red nucleus dent rubthalmic dentthalic and dent rubthalmic So these tracts are passing through what peduncle superior cerebellar peduncle These tracts are passing through what pedunk Superior cerebellar puncle The two major tracts passing through superior cerebellar peduncle are these The only tract from middle cerebellar peduncle is what Cortico pontto cerebellar and rest everything from inferior cerebellar peduncle So why to read inferior cerebellar peduncle I mean everything else is from inferior cerebellar paduncle only So you don't have to read them If it is not denttothalamic if it is not vententral spinus cerebellar if it is not corticopontal cerebellar it is passing through which peduncle only Inferior cerebular pedunk Everything else is from the inferior cerebellar peduncle So my my suggestion here to you here is pedle guys Don't read inferior pedunk because we have maximum number of tract present inferior pedunk So keep it simple Vententral spinal cerebellar dentthalamic denturthalamic that is like epherent the feedback coming from cerebellum These pontto cerebellar from middle podunkcle and everything else is from inferior pedunk There is a long list of tract passing from inferior peduncle dorsal spino cerebellario cerebellar reticular cerebellar olivo cerebellar parolio cerebellar cerebellicular cerebell vestibular If you know the superior pedunk if you know the middle pedunk everything else is from which peduncle only inferior pedunk you can easily eliminate the option and reach the right answer Be smart in this Yeah Okay Now again moving on to few more slides that as you can see I'm just introducing some three four three four three four slides in between in between so that we keep on covering histologology as much as we can Now guys you're looking at a picture Now this time we're discussing the cartilages Now this is a picture of the highland cartilage Now how can you say it's a highland cartilage picture The first of all in the highland cartilage you can see there is a there is a pericontum present collagen and the type two collision fibers there we have pericontondrant present and pericontum do layer guys we have a outer layer of pericontondum which is basically called as a fibrous This this is the fibrous layer of pericontent and can you see these flattened cells over there that's a inner layer controgenic layer outer fibrous layer and inner layer is a controgen layer contour blasts are there but that is not the identifying feature the identifying feature of the highland cartilage is look at that can you see the contro sites which are present in lunar are present in clusters cluster of four 5 4 5 32 all these clusters are present and these clusters are called a cell nest they're making cell nest so three four querytes will come together and they form their own nest over there called a cell rest nest It's like multiple nests are present inside and we have a darkly stained present matrix present around them which is called as a territorial matrix and you can see the light blue light colored matrix present in between them called as a interal matrix So we have a territorial matrix around them dark one and the interal matrix is light one it's a good enough hint to identify it's a slight of a highland cartilage Condroytes are seen present collective like making cell nest having a darkly stained present matrix around them called as territorial and the lightly stained matrix is interior matrix and remember the pericondrome is present it's a slide of highland cartilage what slide is this one now this is a slide of a elastic cartilage how come it's elastic cartilage elastic cartilage again paricontum is there again same thing guys we have controenic layer the same thing outer fibrous layer cellular layer now we have pontroyes present present inside but these condo sites are individually placed Look at these condo sites present over there The condo sites are individually placed here It's not the there's no cluster You cannot make out territorial interior matrix It's like separate separate condo sites are present in this elastic fibers we are not able to see because HN slides can you will not see guys Eioin and hematoxin cannot stain the elastic fibers So I'm not able to see any elastic fiber in this Right So even by the method of elevation also you can reach them Remember controytes fibroartilage may be elastic cartilage highland cartilage contour sites are present in elastic fiber and highland cartilage if the controytes are present in clusters territorial interioral matrix and there is a pericchondrium it's high cartilage if controytes are present individual like this here there is a pericondrium but controes are present over there but the no cellness no territorial interal matrix that is elastic cartilage but if if it's a fibroartilage first of all there is No paricondrium If it's a slide of a fibro cartridge there is no paricchondrium Number two no paricontum Number two the collagen bundles are present in such a way that all these collagen bundles has squeezed these condondroyes in the line Look at the collagen bundle present over there And because of numerous collagen fibers chondroites are now arranged in line in linear fashion And these chondroites arranged in the linear fashion in rows is the feature of the fibroartilage is the feature of the fibroartilage So simple as condraittes individually condes big chondroites can be seen individually elastic cartilage condraittes seen in the cluster of 3 4 3 4 3 4 highland cartilage condoes present in the line in the series fibroartage Simple you can easily identify the the cartilage slide just by remembering these few features only Okay moving on to our last spurt So let's let's finish this off guys strongly So in the abdomen and perennium again a topic which need to be done very selectively This is not I'm not just saying because of the oneshot thing because abdomen and perennium is something OBG surgery the more of a OBG and surgery based question will be asked from this abdomen and perennial So when when it comes to core anatomy some few topics from the per paronium and I would say some topics from perennium that is important especially perennium which I'm going to discuss with you is is is more important here Yeah Now look at this this picture here is a transverse section of the abdomen where you can see the epiploid for let me give you a little orientation first What you're looking at right now in the transfer section guys this here is the stomach That's a stomach over there That's a spleen This is the lesser sack blue color sack over there is lesser sack and this is lesser momentum that is a liver over there and this is a lesser momentum that is a left kidney right kidney you can see the iota there and you can see inferior venne also this where I'm pointing right look at the my laser pointer there this exactly is the point where we have epipoly foramin also called as a foramin of wins that is also called as a foramin of winslow epiplo foramin is an important area because epipoly foramin is a side guys which is the only connection between the greater sack and lesser sack Though this sack here is a lesser sack and everything in front is a greater sack Epiplo forin is the only connection and any hernation through the epiplo forammen is usually a big headache for the surgeon because you cannot increase the size of epiplo forammen Q why can't we increase the size of epiplo for feramin because relations look at just entry to the epiplo forammen what we have what relations are there we have portal triad portal vein can be seen hippatic artery bacter so anti- relation of the epiploic ferammen are the portal tri are there and similarly posterior relation of epipammen are also very important because posteriorly we have inferior vennea we got the right superanal gland yeah right superanal gland and T12 body that that is a T12 bodies there that we have IVC and that's a right supernal gland is also there veins are more important I mean you need to know the other relations also but when it comes to the epiplo forammen or forin means slow just remember that just in front of the epiplo foramin we have this vein that is what that is the portal vein and just behind that we have inferior vica and that makes this area kind of I mean the area where you cannot increase the size what will you compromise can you compromise the portal vein can you compromise the inferior va that's why Increasing the size of epiplo for feramin is not possible and that's why it's it's a difficult hernia to deal with if if the intestine hernates to this epipoly fammen inside and in fact that's the only connection between the greater sack and the lesser sack Right So this is something that you have to remember in the transfer section that's an important important uh opening that you need to know about If you look at a longitudinal section guys once again if you go with the same color code only this blue color space over there that is the lesser sack lesser that is a lesser sack that you see and look at that arrow that is passing through epipamin that tells you that greater the green one that greater sack is connected to lesser sack through this epiplo for ferament the question here is what are the relations of this lesser sack or the omenal bersa lesser sack is also called as omenal bersa and in the in the recent time also they've asked this relation of the omenal bersa if you look at the ant relation of omenal bersa or lesser sack the ant relation of lesser sack is the liver look Let me point just point out the laser on that that is that is the that is the liver corded low of liver this one here is the lesser momentum that's the stomach and we have a anterior two layer of greater momentum also so lesser sack anterior relation we have cordate lo of liver number one you can see in the picture we have a lesser momentum there is a stomach and there are anterior layers of greater momentum per relation of the lesser sack involves the stomach bed structures stomach bed I hope that you all know that what is there in the stomach bed guys what is behind the stomach left kidney left superal gland there is there is there is there is left cr of diaphragm there is transverse misocolone there is a you know what do you say we have a pancreas is there spleenic artery whatever structures are there in the stomach bed are also present behind the lesser sack stomach except spleen that's a question so spleen is a structure which is in relation to stomach work but spleen is not present behind the lesser sac that's that's their main main thing to ask in this guys that which of the following structure is not forming the relation of the lesser sac spleen copiona spleen is the answer to that so in the lesser sac anti- relation are visible there poster relation are the structures of stomach bed except for the spleen spleen is not in the postation Thank you guys Thank you Thank you so much Okay Now this is somewhere which which which this is where I want all of you to focus because there's almost a guaranteed question from this part here that is perennium guys Pelvic diaphragm superficial pouch deep pouch perennial body So I want you just to focus for next 15 I I think I I should be able to finish it next 15 20 minutes only So I want you to focus especially on next 15 minutes which is about the perennium very very carefully All of you just look at the screen and I'm sure that you're going to enjoy this part here Yeah See what you're looking at right now You're looking at the pelvic bone in the lethotic position Pelvis when you look at the pelvic bone from lethotic position guys what you look at that that is the that is a pubic symphysis there right This here is a pubic symphysis This is a isopropigramis tuberosity That ligament is connecting the sacrum and this is tuberosity called a sacral tuberous ligament There is sacral tuberous ligament in the pelvic diaphragm First of all what is pelvic diaphragm guys Pelvic diaphragm is something which is separating the pelvis and parinium and pelvic diaphragm is a combination of three muscle One the three muscle coming from three different part of hipbone and all these muscles are coming toward the coxix coxial vertebrae So we have muscle coming from pubis which is called as a pubo coxyigious that's a pubis cox pubocy we have muscle called as ilioxyigious and we have muscle called as is coxy all muscles are coming to the coxial vertebrae so we call them coxyus we have pubocyus we have ilioxyigious and we have isoxy all these three muscle together are called as what pelvic diaphragm when you consider all these three muscle together that is called as pelvic diaphragm but what's the difference between the pelvic diaphragm and levator NI I'm sure you heard of the word levator NI and pelvic diaphragm are used interchangeably Levator Ni is a combination of puboxyus and ilioxyus guys Iscoyus is not the part of levatory Levatori the muscles which are capable of elevating the anal canal and only pubo and ilio muscles are considered the part of the levatory not is oxyg The difference between the pelvic diaphragm and levi muscle pub ilio that is levit When you say all the three muscle together that is pelvic diaphragm Simple Let's say this is a picture of female perennium Now if this is a picture of female parinium the three openings that you see one is the opening for urethra vagina and rectum Urethra vagina rectum opening Now guys what is a muscle closest to all the three openings That is puboxyus Puboxy muscle is closest to all the three openings So you will see the extension coming from pubo coxys like there is a muscle called as a pubo urethralis pubo vaginalis and pubo rectalus Pubo vaginalis pubure urethralis that is covering the urethra pubo vaginalis that is covering the vagina and pubctalis covering the rectum These three are the modifications of what muscle only Pubo coxyus So pubocois muscle under present and that is sending the extension covering the urethra vagina and rectum and these are the modifications of the pubocious muscle pure urethralis pivo vaginalis and pivot retalus muscle okay now that's pelvic diaphragm for you guys and pub especially pubalis muscle is an important muscle because it maintains the angle it maintains the anorctal angle guys maintains the anorctal angle muscle of continents Okay that's the first look Understand one thing when you're looking at the perennium as let's say this is a this is the pelvis for me So you're looking at like this when you're looking at the pelvis from below So first you saw the pelvic diaphragm Now below pelvic diaphragm there's another diaphragm present there and that diaphragm is present only in this area where urinary and genital structure are present So this is called as a eurogenital diaphragm This green diaphragm that you're looking at right now that is called as a euro because that is present in the eurogenital triangle So it is called as a eurogenital diaphragm But understand the eurogenital diaphragm is having two layers One is a superior layer and one is the inferior layer Inferior layer You're looking at the inferior layer of eurogenital diaphragm This green one is inferior Superior layer is there This is the inferior layer of eurogenital diaphragm which is also called as the perennial membrane This is called as the inferior layer of eurogenital diaphragm which is also called as a perinial membrane guys It is also called as a perennial membrane That is also called as a perennial membrane to story be first it was a pelvic diaphragm Then we have superior layer of eurogenital diaphragm which we haven't seen superior layer of eurogen diaphragm and then we have inferior layer of eurogenital diaphragm And below the inferior layer of eurogen diaphragm now you will see the muscles which are covering the bulb and the crust of the penis Let's say it's a male perennium here So we have the muscle covering the bulb of the pen is called as a bulbos spongiosis And we have the muscle which is going to cover the crust of the pen is called as isnosis Muscle covering the bulb is bulbos spongiosis Muscle covering the crust is called as iskeosis And we also have a muscle which are running horizontally transversely and this muscle is called as a superficial transverse paranal muscle This muscle is present below the paranal membrane So we call it a superficial transverse paranal muscle So guys before we go further uh thank you guys Thank you Thank you so much So when you look at this pelvic diaphragm is there Then we have superior layer of eurogen diaphragm We haven't seen that The green one over there is the inferior layer of eurogen diaphragm And below the inferior layer of eurogen diaphragm you're looking at the bulbos spondosis isosis transverse spendal muscle is there So these are the layers of pane we're looking at here If I take you to the posterior triangle there we have a anal canal there and the anal canal is surrounded by this external anal sphincter guys That is external anal sphincter covering the anal canal and this junction look at this this clashing body over there that junction is called as a parinal body So it's a fibro muscular node guys that that is a region where most of these muscles are converging into this panal body and that's why in especially in the episotomy we are very careful not to injure the paranal body paral body injured obviously the rectal prolapse or the prolapse can take place because it is a common point of insertion of all these muscles what makes the pal parenal body an important topic guys paral body they ask you that that's a picture to compare if if I just look at this picture and compare it what are you looking at right that membrane over there is a panal membrane agreed Panal membrane What is this muscle That is bulbos spongiosis What is this muscle that is is cavvernosis What is this muscle That is a superficial transverse panal muscle And this over there is a external anal sphincter That is pineal body Now the question here is that what are the muscles which are contributing to panal body or mistake usually paranal body What is there in panal body There are total 10 muscles in panal body Out of the 10 muscles guys we have four muscles which are paired What are the paired muscle We have superficial transverse spinal muscle If you have superficial transpinal muscle there will be deep also But there is a deep transverse spinal muscle is also there Then we have what muscle Bulbos spongosis And this is where we commit the mistake Fourth muscle is not this one Let me tell you this is not the issue muscle is not the part of issue muscle is on the side How can it be in the coronal body So it's actually levatory So fourth muscle remember it's not isoconosis it's levatory muscle which is contributing to the paranal body What are the unpaired muscle Unpaired muscle may be have external anal sphincter And because anal canal is not only having the sphincter it is having some longitudinal muscles also So some longitudinal muscles of anal canal are also contributing to it It's a question asked in the exam guys Peninal body what are the muscles which are contributing to penal body So total 10 muscle four paired which makes them eight What are the paired muscle Superficial transverse deep transposal muscle bulbos spongiosis and not is not isoconosis it's levator ni which is contributing there okay now if I take a little section of pennium how it is going to look like If I take a stalle section of penium guys the same thing like if if I if I turn sideways if I take a stalle section the first layer is pelvic diaphragm then we have superior layer of eurogen diaphragm then we have inferior layer of eurogen diaphragm bulb of penis and then we have a choleacia which we have to talk about now look let's say this is a ci section what is this that is pelvic diaphragm we are going from above downward neck first is pelvic diaphragm just below pelvic diaphragm we have got superior layer of eurogen diaphragm Just below that we have inferior layer of eurogen diaphragm also called as what Parinal membrane that is pelvic diaphragm This green one is a superior layer of eurogen diaphragm This red one here is a inferior layer of eurogen diaphragm or pineal membrane This is a mid ceral section So going from the bulb and the shaft that is a bulb and the shaft of the penis and obviously bulb or shaft penis you also able to see urethra Look at that urethra which is passing through that that's a urethra there The question is what is below What is below that For that I need to start from the anterior abdominal wall An anterior abdominal wall I'm sure you all know that on the anterior abdominal wall we have this fasia called as a scarpas fasia Right That is a scarpas fasia is there Swast think that's a good one Scarpus fasia Scarpus fasia which is anterior abdon the the scarpus fasia will continue in the scrotum in the form of the muscle called as a darts muscle We see contamination darts muscle and darttos muscle will continue as fasia called as a kisphacia Guys look at that look at the blue color over there There is a scarpas fasia here This scarpas fasia will continue as what Dartos muscle and then the darts muscle will continue as this fasia which is now called as a kis fasia So scarpas dartos and kohis fasia they are all in continuity only They are all in continity Once you draw this kolasia and you can see this kasacia merging with this parinal membrane here paral descending layer of panal membrane guys look at this one space over there the space which is present above is called as a deep panal pouch and the space which is present below is called as a superficial penal pouch The deep penal pouch and the superficial pendal pouch It is right to say that deep penal pouch is nothing just the space between the superior layer I'm sorry between the superior layer and the inferior layer of eurogenital diaphragm that space is called as a deepen deep penal pouch is a space inside eurogenital diaphragm eurogenital diaphragm space deep space inside the eurogenal diaphragm is deep pouch and the space below the eurogenital diaphragm is superficial pouch now knowing if this is a deep pouch and that is a superficial pouch now there is one very important question which is asked in the surgery also and I want to look at that guys now again I'm putting the same picture for you guys what urethra is this the urethra that you see over there this urethra here is the membranous urethra and this urethra here is a bulber urethra now you tell me if there is a rupture of the membranous urethra urine accumulate if there is a rupture of the membranous urethra the urine will accumulate in what pouch only in the deep end p look at this arrow over there the urine is going to accumulate in the membranes rupure The urine accumulates in what pouch Deep penal pouch Simple But if there is a rupture of the bulber if the bulber is injured the urine will first go into what Superficial penal pouch Now unfortunately superficial penal pouch is not having anterior wall There is no anterior wall of superficial penal pouch So urine can easily come into the scrotum It can even go to the anterior abdominal wall also So if there is a injury to the to the spongy urethra the urine can go into the scrotum and scarpa especially peach pich can even go behind the anterior abdominal wall and maybe to the upper part of thigh also So that is a that is a case that if there is a rupture of bulber urethra then because there is no anterior wall of superficial pouch so urine can go into the superficial pouch into the scrotum into the abdominal wall and into the thigh upper part of the thital holdens line it can go So there are many possibilities if the urine is is if there is a rupture of the the me the bulber urethra So it's a very important question If the membranous urethra is ruptured urine goes into the deep pouch If the bulber urethra is injured urine can go into the superficial pouch into the scrotum into the abdul wall and downward into the thigh upper part of thigh also So if they ask you a question on membranous or bulberra please remember what to be answered in there Yeah Yeah Urine and exel Exactly Krishna that that that that is also possible You may have the urine reaching till the auxiliary wall also Weird but true Okay Ch guys coming to this last gross topic here Issue rectal fossa or issue anal fosa I'm just going to wrap it up in the next 5 10 minutes only Isurectal or issue anal fossa What is issueal fossa If you look at this anal canal that is the anal canal over there This here is a skin of the glutial region I'm just comparing the picture square the glutial region and on the lateral side there is a muscle which is called as a opterator internals There's a muscle here There's operator lateral wall is operator internous muscle If it is a anal canal guys obviously that is operator internals and that's this is external anal sphincter that that over there is external anal sphincter and this is the levator ani that is levator You can compare this with this picture above guys You can see this here is the opterator internal muscle This is a external anal sphincter There you can see and this obliquely placed muscle is levator ni or you can say pelvic diaphragm Levator n or pelvic diaphragm is there Now look levator Can you see the fasia covering the operator antennas It is called as a opterator fasia And this operator fasia it gives rise to a canal on the side which is called as a pudendal canal This operator fasia only will give rise to a canal and this canal is called as a pudendal canal Let me just try to show you the pudendal canal in this picture also Guys I thought a cha picture but I hope you can still manage to see Can you see a little canal over there on the side here Look at that here That canal which is made up of operator fasia It is called as a pudendal canal It's the same pudendal canal which is giving passage to the pin structures guys Pudendal nerve internal pedental vessel they will be passing through this pendal canal You can see pundal nerve is going through it and internal pedal vessels are also going through this pental canal only Now so first of all bound if this fossa here is is guys this is the iso rectal fossa So I can say in the isal fossa the medial boundary fural fossa is by external anal sphincta and levi and that is eura medal boundary lateral boundaries by operator internals and that operator internal fasia is forming this pudendal canal also holding the pudendal nerve now if I see this in the transverse section if I look at the same thing in the transverse section how it is going to look like now look if you look at same we already have discussed this area so I don't have to talk about this region guys we already discussed this now I want to take your attention here in this picture you can already see Anal canal there you can see the external anal sphincter Now pudendal canal is present something like this roughly pudendal canal is present on the side and this pedental canal is giving passage to what nerve pedental nerve and internal pedal vessels That's a pedal nerve and internal pendal vessels are passing through it If you have a patient who's having a isal for fossa absis now you can easily put an incision like this You can drain the isureal fora no problem But there is one nerve and there is one artery which is actually running transversely in the isurectal fossa called as inferior rectal nerve and inferior rectal artery And this inferior rectal nerve and artery are vulnerable to injury in the drainage of isurectal fossa The isurectal fossa main content of fat There fat is a content Pendal canal is a content but the problem is these contents because rest of the contents are very safe on the side These are the only structures running horizontally in theal fossa called as inferior rectal nerve and inferior rectal artery So if you have a patient who is having isrectal fossa absis while draining the absis you may injure these structures These structures are vulnerable to injury in the drainage of isoctal fosa absis That's the main question they ask you in the hiral fossa that what are the structures which are uh which are which are you know which are vulnerable to injury in the drainage of hural fossiapsis and the answer is inferior rectal nerve and artery inferiorctal nerve and artery Okay Finally the one last slide for guys that is a question which is also asked in the recent time that is about the tongue papill Now when you look at the when you look at the tongue pap see just I want you to notice very few basic things here you don't have to go into too much of detail and histological part of it it's easy to identify the pap first of all you have the filifform papa which are like conical projections are there and the filmform pap they do not have the taste buds forget about it so that is filmform pap there's no taste bud on the tree now we have fungyiform folate and valid papa in the fungy form papa you can see there there are These pits are there We have these these pits are there on the pil on the side here Right The taste buds are present on the dorsal surface on the surface On the top surface we are the taste bud So if you see the pits are present on the side and the taste buds are present on the top on the dorsal side It is a fungy form papa It is slightly mushroom shaped But the problem is surface If you have the straight pits if the pits are straight you can see these pits over there They are more or less straight only But the taste buds are present inside the pit not on the dorsal surface Can you see the the taste buds are present inside the pit not on the dorsal surface it's a folate papillary And if you see it is mushroom shaped shaped like fungy form only it is mushroom shaped But the instead of on the dorsal surface if the numerous numerous taste buds are present and these taste buds are present in the furrow in the spits then it is valid or you can say circumalid papa based on that the question given in the exam was this one Can you see that it's a folate pile now How come it's folate type Because first of all you have a straight furrow Straight pits are there And guys it may enlarge this Taste buds Taste buds Taste buds Taste buds Taste buds All these are taste buds present in the furrow There is no taste bud present on the surface Nothing on the surface If it was present on the surface it would have been the the fungy form This is a folate pile Let me show you the one which is more like a mushroom shaped And you again have the taste bud present That would be validate or the circum And that is this one Look at that Can you see First of all the shape is little like mushroom shape Broad above and narrow below And if I take you again nothing on the surface Nothing on the surface above But look at the pits over there And look at the number of taste present inside There's so many taste present inside There is what papa that's a circum So keep it simple Conical projection like this form Then we have the one which is slightly mushroom shaped but the taste buds are on what surface That is what fungi form If you have mushroom shaped but the taste buds are present in the pit that is circumvalid pap or valid pap If you have more like a straight furrow and the taste buds are present in the pits then it's a valid pap So whatever kind of taste this the this taste buds are given to you I'm sure you will be able to identify they will give you circumulate or folate peple only to identify two to kind of fight between the two like yes so that is about the swast major yeah hello guys so that is about the valid pap so guys that concludes the discussion of this the whatever time was committed to you the we we are able to finish it on on on that time itself Okay Yeah So guys this is about this is about the anatomy one shot the many of the people are asking that in the anatomy one shot that how much is is it enough or it is it is I cannot say how much is enough but I'm pretty sure that if you have done this much you will not come disappointed for the anatomy or out of examination hall you will be able to if you are someone who attended my lecture earlier and you're now looking at the oneshot it is very very beneficial but if you are someone you have never read anatomy or read anatomy from other source Whatever experience you had over there let's not talk about that And if you kind of want to rely on this on this uh on this one shot still it is not going to disappoint you I can promise you that And that you can see in the in the int which is very very uh if it is going to happen in few days itself you will see that how much of anatomy you will be able to attempt in this If the INCT gives you a confidence from this one shot then I think you you will you will gain more confidence out okay I can carry this the same thing forward into the the neat exam also and you know guys talking about the exam I I just just want to I'm not going to preach or anything here but I'll tell you one one thing about the examination that there are so many expert faculties who have whom you have met and they have given you such some great suggestions here I just just want to tell you a little you know a little fact about it about this examination all even you know Even at this age even at this point of time in my life even even if I sit in front of the of the grand test or the question which are asked in the exam for you people I start having anxiety PG exam I don't have to do anything now but still I get an anxiety here so it is the pressure which is basically refraining you from where you want to reach example guys if I put a plank if I put a two feet plank on the road and I want to walk work walk on this plank will you be able to walk on it effortlessly Two feet two feet plank We can jump we can jump we can dance we can stand on one leg we can do anything effortlessly We can do that right The two feet plank The same two ft plank Let me put it on the edge of the building now Let me take the same two ft plank and I put it on the edge of the building top of the building here And now I ask you to walk on it here Now what happened You're trembling You're not able to do it You're not able to walk We same It's the same plank only Now it's the same two feet plank on which you were dancing just a minute earlier and now you're not able to walk on it here The reason it's not the plank It's not your ability It's the fear It's the fear of falling It's the fear of consequences You're like what will happen if I fall down while I despite of it's a very easy job to be done because the fear is something which is creeping in that is not letting you do it This is exactly what happens in the examination All when you're sitting in front of the screen when the questions are triggered in front of you the question which is not not scaring you It's the question and the consequence which is coming in your brain If I got this question wrong then one wrong is there negative marking will be there that'll affect my rank This keeps on going on in your head and that basically you know affects your the entire thing The people who are able to do good in these examinations in this PG entrance or any entrance examination are the one who are able to handle themselves mentally better So you know at on the given day when you're in that examination hall your knowledge obviously is counted but I I I very genuinely feel and it's very generally I'm saying it's not just just to you know just to show you some pictures and to motivate you only it that it's it's about how confident you feel about it how you know you feel that the result doesn't m matter easier said than done obviously I as I said even at this age I can't do that so so effortlessly Because if I give you the same questions in a test sitting in comfortably in your hostel or or bedroom you might be able to do it The same question on the computer screen when the neat exam is going on the pressure the environment the consequences what result is going to do is basically going to pull you back here That's why give grand test as many as possible especially with all these the uh the national grand test that we have so that you basically get you know sometime you get a good start sometime you get a bad start you just basically learn to walk on that 2 ft wide plank be it on the top of the building or on the flat road you should be running effortlessly on this and with that I thank you so much guys I I I hope that this one short session not only mine my I'm the last one here I was supposed to be on the fourth day that they helped you kind of helping you to revise your subject um efficiently And one more thing on the 16th of uh of this month we are also having uh the marrow is also you know conducting this if I may tell you uh on the uh to support your you know the preparation a free marrow mock test will be live on the 16th of May after this for this one short thing here So I would it's free why not do it So please go and give it and and and just make sure that uh you attempt it uh with with whole heart and I hope that uh that is going to add up something more into your preparation So guys I'm not going to take much time of yours I've I've been eating your head from last almost four or five hours I'm sure you must be hungry for your lunch and I'm take a bow Thank you so much and do send me your messages on my telegram You all know that about Telegram my inbox and wherever you can Your feedbacks is is the is is is the most desira desirable thing that that I want from me Thank you so much It's 2:33 a.m in Calgary The temperature outside is 10° It's pretty cozy And uh once again thank you so much for staying with me for so long and attending this session Goodbye Take care God bless you all