Transcript for:
Understanding the Skull & Skeleton (Module 4)

Hello. So when we look at the skeleton we have all these bones but we can sort of differentiate between the trunk stuff and the extremity stuff. And so the trunk stuff we call that the axial skeleton. Right here, axial skeleton. So that's, well actually that's cool to do because there's a slide for it.

The axial skeleton is the head, what we're going to talk about today. Basically everything in the midline. It's like an axis in a car so to speak. So it's also the bone down here, that's a hyoid bone.

The one right in here, if you squeeze it hurts a little bit, that's a bone. Then the breastplate and the ribs, that's all axial skeleton. And of course, the spine in the back. The vertebral column is also axial skeleton.

And the appendicular skeleton, oops, the appendages, are then the upper extremities and the lower extremities. And so that's sort of how we differentiate those two things. And then where do we separate from actual appendicular is then a question if we have to categorize this stuff.

And in the upper extremities is the pectoral hurdle. the pecs are these muscles in the front, right? So we call that the pectoral girdle.

And the shoulder blade, your scapula is your shoulder blade, and your collarbone is the clavicle. That is considered appendicular. skeleton and everything more medial to that will be axial skeleton. So you want to know these bones so you know. If I would ask you questions, is this bone appendicular or axial skeleton and I point to the shoulder blade that would be the part of the appendicular skeleton.

And it has to do with how stuff is attached. You know, the shoulder blade is already partly moving for the upper extremities. So there's already the extension of the trunk, so that's why they include that. And then in the lower part it's easier, it's just the pelvis is that different. And the pelvis, I specified out already here, is three bones.

It's the ilium, the ischium, and the pubis. Those are three main bones. They look like it's one bone. When we get there, yeah, remember pubis here in the front? Yeah, that's the pubis.

That part is the pubis bone. And then this is the ilium, and where you're sitting is your ischium. The sit bone is the ischium.

But we'll talk about that when we get to that. Because for us, that's just one bone. Yeah, some bones, they keep the names like, even though it's one bone, they still keep the names like they were in the utero, like before it was fused.

So that's that. So axial skeleton, like the axis in a car, is the thing that goes between wheels. So it's kind of, for us, that's the axis. For us. And then the appendages come off of the axis.

So, that brings me to the head. Bye bye, Mr. Hamilton. I'll see you later. oh i didn't take these out yet that's from the old book if you get the book that's the page in the book um the skull is two parts to it it's just the brain thing that calvarium we call that also the skull cap and then we got the face we got facial bones uh that make up the face the skull holds the brain and the face you know makes us be able to eat and smile and all that kind of stuff uh when we look though at the the head we don't have to if you look at your head over there that table it looks like it's one bone but you've got these jagged lines on top of that bone you see pick it up you see the jagged line things you can actually touch it if you have ridges in the top of the head that's a that jagged line thing and and that and that jagged line thing is actually a joint you know a joint like an elbow joint but it's a different joint it hardly moves joint so jump joints don't move technically speaking that pelvis that we just talked about between these bones those are joints and we're gonna have a chapter of joints so we don't get ahead too much the joints are not be a big chapter for us but these these these raggedy lines they actually can or their bones on either side so that the lines are called sutures and and and they are the joints of the skull so we have multiple bones that make up the skull and would you know they actually move a little bit Very, very gentle.

Have you ever heard of craniosacral therapy? No? God, we got stuff to talk about. That stuff is good stuff.

I got a few bones to make up that head and the frontal bone is one, the parietal bone, we got two of those, temporal bones, occipital bones, sphenoid bones, and ethmoid bones. Holy cow. So, I've got the collar ones, so for me they're all collared.

So the frontal bone is here, in the front. I like when that works out. The frontal bone is in the front.

So if you forget what the frontal, you just remember that. You're walking on water, front first. Parietal bone is the big stuff on the side, so the main pieces on the either side here. And then the temporal bone is where the ears are. Ears, not temple, ears.

Temporal bone, ears. Occipital bone is the back of the head. Nice and rigid. Strong this is weak.

I had a patient walk in you can take this off It's very skinny. I'm not sure is this caviar back there unlocked also one of those Too bad I Wonder if the individual bones are somewhere I'm gonna have to look around but but that's that Ball is very skinny on the side here So I had a patient walking once that was years back and she's like I have always migraine I have and I'm like something's weird here. Did you get hit? She go ahead. Did you leave him?

Uh-huh But that's very dangerous because this is very very very flat bone and it's very skinny. You could break that thing easy So, you know, it's not just because you gotta handle that stuff, no, sometimes it's dangerous. So that's the temporal bone, occipital bone, and then the sphenoid bone is weird.

The sphenoid bone you can hardly see. If you look here, you see that yellow thing? Going from side to side underneath?

That's the sphenoid bone, that's like a weird bone. See that in there? That thing. It's like... in the inside but it's an interesting bone because every other bone touches that bone so yeah have you ever had a concussion you know you hit your head against something real heavy and it's like headache and it's like everything's off now then the lights don't match up is not good then you need to sit down um But when you have a concussion, some of these things get stuck.

The sutures don't move a little bit. The fluidity goes away. It's not like they have to move a lot, but a little bit.

Because there is fluid inside the brain. And we need to be able to move that fluid around. And if you hit the head with something on the side of something really hard, it jams it. And this bone becomes crucial.

Because if you can move this bone a little bit, you can unjam things. So that's very interesting to me. Yeah, there's a technique that I learned. You actually take, you know, a finger, a finger, a finger glove thing? Like if you, the plastic gloves, which is for a finger, a finger cup.

You put that on a blood pressure, figuring out the blood pressure pump thing. And you guide the balloon a little bit up into the nose right underneath here and you pump it up and it pops the bone back. It's very effective.

It seems really awful but it's a balloon. It's not that strong. It's not a knife or anything. is really in a lot of trouble and a lot of whiplash problem and headaches then you do that a few times and it helps a lot my teacher did somebody who hit her head on a wall and a half pipe and and couldn't stand on one leg and six weeks later she won the gold in Vancouver because he did that to me gonna so that's not cool but that's why something like that would work And the ethmoid bone is taken away here. It's deep in the nose.

So as you look up in the nose, it's all kind of, it looks like it's kind of, there's a whole bunch of stuff up in there. That's ethmoid bone stuff. So we'll talk about that. And then we get to the face and the facial bones just to briefly go through.

There's a bunch of them too. Look at that. The maxilla and the palatine kind of go together. It's the upper roof.

So the roof of the maxilla. mouth the purple one is that maxilla so you want to definitely know that bone that's a big one and then the nasal is by the nose the lacrimal is where you cry in here too there's a very small little bony things we just touch on those the zygomatic bone is an interesting one though that's the blue one that's the cheek the cheekbone so that that one i love that name so you better learn that because i'm sure it's gonna be on the test You know if I say that, usually that is actually on the test. So you better start.

And then we have a couple more. We got the vulva bone. That's that.

Look at the red bone. See that red bone? It's a sliver just underneath the nose. You poke it hurts when you poke it too heavy.

Be careful. That's the vulnerable. It looks like it's a plow.

The verb means plow. Like you know, you plow through snow. You plow through snow. kind of thing.

And then the inferior nasal conch shot, that's inside the nose, these wriggly things on the side of the nose. We'll talk about that when we get there. It's a little bit weird. And the mandible, that's the other big bone that goes sort of with the maxilla, it's the lower trouble.

That's why I moved. So Monday, today's Wednesday right? Today's my birthday.

So I didn't go to work. I just come here. So I think it's Monday because Monday I don't have patients. I'm like hmm. But on Monday we're going to talk about the facial muscles and that is this stuff but also the stuff that makes us chew and that's going to move the mandible.

So there's a couple of types of muscles. Okay, let's go a little deeper in these things and we look at the frontal bone first. It forms the forehead. Okay, good. It makes the superciliary arches.

Well, that's the eyebrows. That's the eyebrow arches. Oh yeah. The lacrimal bone.

Yeah. It's not on here huh? We'll get to it.

It's somewhere here. Ooh, ooh, ooh, ooh, ooh. There it is, see? We're gonna have the nasal right by the nose.

And the lacrimal is right in, you know where you get the sand man in there? Like morning when you wake up, and it's like the stuff is in there? That's in there. Because the lacrimal... is where where where the tears when you make tears the tears are made on the outside of the eye socket and then they move across the eyeball and then they go through the lacrimal into the nose that's why we need tissues where we cry a lot I mean it's for this but also because of the nose and the lacrimal bone is what has that hole in it that drains that duct that drains that felt the tear duct good so we've done that now that's good So back to the frontal.

I didn't catch that that wasn't on that list. That was a good catch. The superciliartis are right here above the, you know, eye sulcus, basically.

That's where you have the eyebrows. And so the eyebrows, you know, the eyebrows are kind of cool. They actually catch perspiration. don't get all that salty stuff in your eyes and it burns when you're sweating. But also it's a little bit of a hack.

So it's a little bit of a shave. That's the eyebrows. Of course the frontal bone is a lot of the top of the orbit means the eye socket.

That's orbit. Oh, and of course the most important part is the glabella. The glabella is the part between the eyebrows, right here on top of the nose, the bridge of the nose, and it means hairless. And it rhymes with my daughter's name is Isabella and it's always on the test because of that.

And I want to go see her because she lives in DC this weekend, so I'm very excited about that. Also, the frontal bone is, when we look on the inside, look right here, on the inside, look, you can take the head off, the top off your bone there, take the top off of your bone, if you could. So that looks like that. Yeah, there's a few things on the side, make sure you don't break them. So on the side.

And when you look in like that, you see there's like three parts where, like three different levels where things can... sit in can you see that so you got the front is a little higher the middle is a little lower by the hole and then the back sits down over further so the frontal part this part on top here that's the that's that's what they mean by forms the anterior fossa of the base of the skull so that the anterior fossa is that front part there's a slide we have a middle fossa and a posterior fossa it's not it's not a terminal is so it's not too great you know as a term but that's what it is also it's got the sinuses in it the frontal sinuses you know about sinuses They're like whole pop. Yeah, you feel them sometimes. I don't know.

I feel them sometimes. I try to do neti-poly. So it doesn't get all stuffy. But the sinuses are chambers in the skull so the head is not as heavy.

And it makes the voice resonate. So you can be really loud. Don't need a microphone. So that's sinuses. I think we have a slide on sinuses.

That brings me to the parietal wall. No, the parietal bone. That means wall.

So that's the big bone on the side of the head. That's the yellow one over here. And that bone... It doesn't need to have too many landmarks. Parietal laminate, that's just the widest part.

The reason why that's important is because when the babies are born, that's the widest part of the head. The skull's got to squeeze through that birth canal. That's kind of a tough situation, so that's what's going to squeeze. The reason why that's going to be able to squeeze is if you actually look at...

See here? These jaggedy lines? These are the sutures. they're like this, jagged. But then you got one on the side, they're like, it's all this, it's flat.

When you look, that's that, that's that when the temporal bone comes in like that from the side, and they lay over each other like that. And so when the head gets to the birth canal, you can squeeze the tops together, and there's no jaggedy line, it just goes underneath, and it squeezes that way. So it's really neat. It's a very smart concept here.

And evolution, huh? Somehow. That nifty thing. That nifty thing we got. The other thing that's important on this bone is that landmark if you look at your skull is really tough to make out.

So I don't think it's on my list. Is it? Yeah it is on the list for homework.

Um, you see this here? The artist can draw it. And that's where you have a muscle attached.

So if you actually take your hand and just put it above your ear, and you just clench your teeth, you feel the bulge? That's that muscle. That muscle is a chewing muscle. So it's attached right here.

That's the superior temporal line where that muscle goes in. So it's sort of flat, but on a real skull you can feel it better. Now who? No, the wide part is where the muscle will attach. The muscle is right here actually.

I put it there. So see it goes right into that area where that is. So very often when you have some, this is a bad example because it's not really rough, but when you have roughage, like, look, turn your skull upside down, and you have that hole right in the middle of it, and then on the side you got these...

stomps coming out. Yeah these, they look, these are behind the ear ones. You actually push them, it hurts a little bit. But that's muscle attachment. So a lot of times when the bone looks rough, it's got a little, little roughage around it or it's got a bump like on the hip here, it's got a bump on the side, like this big, this bump over here, that's muscle attachment.

Most of that is muscle attachment. Otherwise why would it be there? That's always a good, this is a place where the why question is good.

Not because you want a different answer, like the kid, but because we want to know. And without the why, we do not ever get to the next one. I want you to learn, I want you to study as little as possible. Do you know how that works? You understand as much as possible.

When you understand it to study, then you gotta squeeze it into the head somehow to remember it. But that's where the flash card shows up. Because once you understand, you just remember the understanding and then you're gone. I'm very kinesthetic, like that feely thing.

And so I have to like feel these things. I realized in chiropractic school, it's like I almost have to feel. And then I talked to my old head of the department and he's like, you know, when I analyze and read, I have to...

to like interact with the material otherwise I fall asleep and I'm like you were an academic and it still happens to it's not just me and I'm like hmm it's not just me so I think it's really difficult for many of us to just sit down and so I have to work the material guess what I'm doing this kind of stuff that's how I work my material once I know this I know it and so that's sort of the process but this stuff yeah the why is very important and With biomechanics you can ask me the why fairly well. Oh look here, sutures. We have the sutures.

These are these jagged lines. So see we got one right here, this is the frontal bone, this is the parietal bone. So you got one right here between the frontal and the parietal bone.

They call that the coronal suture. The crown, the corona, is like that. So that's this way. And then we got another one right here between the parietal bone, that's the...

Sagittal Sutra, that's the Sagittal Plane, chapter one, Sagittal Plane. So sagittal suture. Then we got, we're going to get to the next bone. Two more here that I want you to know. One is called the landoid suture and look at that.

That never really shows up well. But I'm on the picture. But here. If you look back here, you see how the sagittal comes down and then the occipital bone here, that's the occipital bone, the suture goes downward like this. And so that looks like a lambda, a Greek lambda as a letter, so they call that the Landoid suture.

So that's a stretch, that was midnight when they came up with that name. There's a lot of wines. I mean you've got to figure out how do they give these names to these things.

It's got to be that, right? And then we've got the last suture is the one that I talked about on this other slide where the flat one that's between the... temporal bone and I mean the temporal bone here and the parietal bone here and that's called the squamous suture because squamous leans flat so that's the flat suture that way when we get born it gets to be squeezed to the skull can squeeze together without having these jaggedy lines coming to the way so that's where the sutures fontanelles oh you remember when you were a baby I was never a baby You know I'm still a baby that's the problem. Sometimes.

When we are born these cold plates are not fully formed because yeah we gotta squeeze that brain out into the world. Have you ever seen a cold head when they're born? Sometimes.

Sometimes it takes a while for these plates to come back down. That's the conehead thing. I mean, that is the look.

Just don't say the kid later. That's when you want to have this craniosacral therapy. That's when you go to an osteopath or so if your baby's born with a conehead, you call me up and say, what am I going to do about that?

And then we'll figure it out. But you have my number, right? But we have two main places where the skull plates do not meet yet. And that's the anterior and the posterior fontanelle.

The soft spots. Those are the soft spots. If you have a baby, you know the soft spots. Otherwise, shame on you. Never touch the baby.

Because the baby needs you not to push on it. Because underneath is the brain. Don't squeeze the brain. Remember in the last chapter before that testing we talked about how bone is made intramembranous ossification where you have two membranes and in between the bone starts growing? That's the leftover remnant of this membrane and then the bone will fuse when the soft spots close up.

I need to find these all the time on the dogs when I need to look some reference points for the skull when I do some work. So these come up all the time. Feeling a lot of fontanelles.

That brings me to the temporal bone. I like the temporal bone. Now let me, let me, yes?

Wait, how long does it take? Oh, that, I need to look that up. I can't talk too long for that membrane there.

I don't remember that. Look at that temporal bone. Oh, that's too bad. They label the things with temple bones and there's nothing in it, so that doesn't help. No, I have to look it up, right?

It's weeks or months. Anybody remember? You guys got kids, right?

Young ones? Well, how long does it take? I think the one is five weeks, five weeks, the front?

And then the front is much longer, yeah. So don't, if you don't know about these... Don't touch your baby that's on her ear. All right, Peprobond.

It's one of my favorites. That's the one behind the ear. And I do need this. I should use this. So what do we have there?

We have a very thin, I talked about that already, there's a very thin part. That's sort of this part. It's called the squamous portion. That's right by the suture.

I don't think that's on my list of labels. I try to to be clear about when I do the test if you have ambiguity like you don't know which piece I mean for what I do not want you to test on questioning yourself that way so like there's points that are close together I'll take both All right, so and just make sure ask me questions over and over that way you get it so That's the thin portion then a big a big landmark for the temporal bone is There's a few big landmarks on this one actually is that mastoid process? So when you when you go behind your ear you go behind here that is a bumpy thing You feel that bumpy thing it hurts a little bit when you push hard It's the mastoid process.

Yes The psychomatic? Yeah, are they the bones? Are they...

You mean parallel? Yeah, like you see how they have them right there on the picture where it seems like it's almost one bone? Oh this?

Or what? On the little one. On this?

Yeah, you see how the little one... That is one bone! Okay.

That is when you look at that... bone you got that whole weird stuff around everywhere yeah yeah yeah and then yes this the zygomatic bone which is the one you mentioned right this jesus that comes off for him so that bone goes from here then he goes forward and there is a little bit of a place place you can actually feel if you really feel it and there is that little cut that's a suture and then it's continuous to the front then it's the cheek so if you get good at palpating you feel that little bit and so that would be right here so yeah you have a few landmarks you got that bump behind the ear then you got the ear hole and then you got the stuff in the front where actually you got a place where the mandible sits in where this comes together where the jaw bone comes in and so when we then we have the mastoid process is the back bump here and then we got the what is you put the external acoustic meatus that's an important term that's that that's the ear hole they call that acoustic or also they call it auditory and me a this means what does mean canal get out channel so they also call that external auditory canal or external acoustic canal or external auditory maintenance they mix these names up around that so if you know miatus means canal that's good to know that's a flash card right there there's these terms they come back over and over if you do bio 2 right file 2 a lot of these terms come over miatus comes back over and over canal and the word acoustic you put acoustic aka also known as auditory and then you can fuck someone around with them if somebody gives you attitude you can mess with their head a little bit I had this guy he came from Southern California and I was talking to him what's up with him and I was like you know the bones a little moved over there and a little bit over there and a little bit over there and the muscle feeling also and he's like, you really a chiropractor? I was like, oh, so sorry.

So let me start using this like a pulp seal joint and blah, blah, blah, blah, blah. And then it's actually good to him. So sometimes you've got to BS it a little bit. It wasn't BS, but it's still. kind of weird why would I not talk in a language that everybody understands so anyway the next one so that the master process the external acoustic meatus and then here in the front is where the mandible will sit in and come in from underneath and that's known as the mandibular fossa and fossa is another one of those terms you make a flash card with fossa means a shallow depression a fossa is a shallow depression it makes a jump so here you go up the the fossa and then from underneath the mandible comes in the mandible comes in and sits right here sits on into the fossa so actually let's do it on this by the end of my lecture this whole thing is taken apart you see it on here you see the mandible is this one and of course here it's not in there the fossa is right here so this piece is the temporal bone so you have mastoid process external acoustic meatus mandibular fossa name after name that's the game the name of the game makes sense yes the medieval fossa makes the joint with the mandible And then we reference back to what's called when we get to the mandible.

Because then you've got the piece in the mandible that goes into here, and then we call that something. Everything has a name. They were really bored in the Middle Ages.

Everything has a name. The Petrus portion on the inside? Yeah, let's get to that.

That's another one that I like. The Petrus portion, take your head off. Look on the inside. And I don't have one on me, but can I borrow that real quick?

So when you look on the inside, this is the front, this is the back. You have the big hole there. And right on the hole to the front, there is like these ridges that come off.

These two ridges, one on the left and one on the right. You see those? You feel those? Right from there is the middle cranial fossa, and it drops down to the back of the head. So these ridges are the Petrus portion.

That's those ridges. So that's the Petrus portion. And what we have in there is our ear. Hearing stuff. So the outside here is right here and you go to the inside and then a continuation of that hole is that Petrus portion and in there we got that snail thing.

That cochlea. Have you seen that before? How we hear it?

How we hear it is so cool. It's bending hairs and then we hear it. Every time you go outside, you have a sound coming in here. The hairs bend, make a nerve impulse. So that's the pectoris portion.

And then we've got a styloid process. We're going to point that out. And that's right here. Styloid process.

And you can't feel it on yourself. It's a good thing because it will break off. On your skull, on your knees, it's just a little thing that comes down and you think it's probably a mistake.

It's right here. See right here, that little thing that comes down. It's muscle attachments.

If something sticks out like that, it's got to be a muscle attachment. Otherwise, why would it be there? That's always the question. The body is really smart, but it's layer two. So it's not just smart, it's also evolutional.

I think it's evolutional. I had this discussion with a patient who asked, so tell me about your body. about the body is it very how intelligent is it okay it's good well let me tell you something he brought me some moments to read up on and then we went to talk about the creationism and the evolution and it was like a really interesting and I had to still work on him and and and i was fine with it but it hit me at some point that oh god used evolution in an ever-changing life form as his creation so it all works out it's actually not one or another it's the combination of both um and so when there is a stylus process something like that you go like why the heck would that be there because it's totally aberrant it doesn't make sense because you can break off so easy so then we come mostly in the bones we get to muscle attachments. That's a big, big answer to that. Alright, so that's the temporal bone.

What did I miss? The zygomatic process. The zygomatic process, zygomatic is the cheekbone. We'll get to that. The zygomatic process comes off of the ear bone, the temporal is and goes towards the cheekbone.

So this thing that comes off the temporal bone towards the cheekbone is called the zygomatic process. At least there's some logic with that. right all right good occipital bone the back of the head that's also a cool ball that you're looking from underneath so if you if you have the big hole the big hole is where the brain goes up and down spinal cord break it's actually brain stem still goes down there um next to the big hole Our, our condyles, the condyle is a good, occipital condyle, see here, occipital condyle. Condyle is a very good word, that's a word that makes a joint. You got them in your knee, you got them in a manual, you got them, I have to think, but there's all over the place.

If you see the word condyle, you're thinking of making a joint, joint surface. So these are the condyle right here next to the hole, the foramen magnum. And then the last one here I want to, if you touch the back of your skull you feel that bump. There's a bump. That bump is known as the external occipital protuberance, EOP.

Bump. Bump in the back of the head. Why would there be a bump in the back of the head? Muscle attachments. I mean maybe also if you fall on the head there's a little more protection but mostly I think it's muscle attachment.

And then these are the places here where articulate means making a joint. Articulate is a word for making a joint. and so the occipital condyle articulate with the first vertebra so that what that means is like here the head the head is going to have a joint with the first vertebra right here that's the first vertebra that round ring on top and that's right here where these condyle sit down onto the first vertebra that bone is known as the atlas because the greek mythology the atlas holds up the world for us the atlas holds up the head that's our world I don't know.

I'm not so sure about that. I think people have more smarts in here than in here, really, all. And a lot of them have it really in here.

I know, you need that gut feeling. And that's the cranial fossa. I think I talked a lot enough about it.

I'm not too concerned test-wise. But if in another class you get to, here it is. This sphenoid, I love this sphenoid bone, although it's a hard one.

It's a bat-shaped bone that is the keystone bone of the cranial floor because all other cranial bones attach to it. That's what I explained before when we talked about it. When you open your skull up and you look on the inside, you've got that hole. And then a little bit in front of the hole, you've got a little thing you can put your finger in.

It's known as the salatursika, or Turkish saddle. Is there another skull back in there? Can somebody get me one, please? I'm sorry.

I should have brought one up myself. The salatursika is where we have a gland sitting in. Thank you so much. It's known as the pituitary gland. So we have foramen magnum, cella tursica, that little thing that you put your finger in.

And it's basically a place where we can put a gland in, and glandular tissue is epithelial tissue, and epithelial tissue is very, very regenerative. That means it always grows. The brain, not so much. The brain is very soft. It's like jello.

I mean it's really soft. We have some brains, we're gonna see them later. And when you have a tissue that grows fast and a lot that can put push into the soft outer tissue like a gland, you want to protect. the brain from that happening and so that's why they enclose that thing that gland in bone as much as they can enclose it in bone and that place where that's it is the cell of Toursico because it looks like a Turkish saddle somehow you visualize squint your eyes have a glass of wine visualize this will tell you I mean you didn't hear from me right We got greater ring, we got lesser ring.

When you take it, I have, you don't have to disarticulate it. They call this disarticulated bones. They have to draw it, but they don't have the bone in it yet.

But when you look at that bone, you have a little sliver here. and then a bigger sliver on the bottom. They call that the greater wing and the lesser wing.

Off the bat, that's flying. Like, you know, it's flying like that. So the greater's on the bottom?

The greater's the bigger one, yeah, on the bottom. And then, you know, that's the frontal, basically the frontal cranial fossa, a little bit of it, and then that's the middle cranial fossa, so that's the difference between them. We have sinuses in there, sphenoid sinuses.

The sinuses that really suck are these. Well, actually they all suck sometimes, but these are the ones that get infected the most. And then the other thing that's interesting about this bone is when you look down, you see these things coming down at the bottom? That's like in the back of the mouth place, like all the way back there.

See this is the mouth here. You turn it out around and then look from the back in and you see these two things coming out. That's the sphenoid bone. That's the places that give us muscle attachment for muscles that help us to chew it.

When we're going to look at the chewing, we have muscles on the outside, two of them, and then we've got two on the inside that help to chew. What bone is that? Sphenoid.

Sphenoid. That's the pterygoid processes. Oh, yeah, I should say that word.

Pterygoid processes. That's a cool word, too. I don't know who came up with that.

Must mean something. You can see it on the bone here, the pterygoid processes. but it makes more sense when you see it in real life what's going on with it because otherwise it's just some abstract thing all right it's phenol ethmoid means seed so when you that's the stuff behind the nose the ethmoid is behind the nose so it's really brittle in there if you have a real skull and you put your finger up it'll break so when you when you look inside of here you see Then you've got a line going up and down. And then you've got some things on the side that come out from the outside to the inside. They're like hold.

They like go down like that. So we have the perpendicular plate is what goes up and down. That's the open down thing that separates the nose between left and right nose.

And then we got these nasal contours. These are these things that bend in from the side. And what they actually end up doing, they...

They end up making the air that we breathe in moist and warm because they create turbulence when you look at when you think about the flow of the air that goes in here and these round structures the air will start turning around it's slowing down and warming up but getting moist so when it gets to the lungs it's nice and what it needs to be we don't feel that here but if you go to Chicago or something you were outside in the winter and you just go jogging and you're over lever and you breathe with your mouth, they go burning down the throat. If you breathe with your nose, it's much easier because of that. So that's cool.

So that's part of that bone. That's known as the conscious. We have three of them.

We have a superior, we have a middle, and we have an inferior. And the inferior is its own bone. So we'll get to some of that. Then there's another thing here, these two parts here. When you take your skull and you take the top off, you look right here in the front.

And you see, you go over, you think that's an end, that's where the plastic came together or something, but it's really a thing. And that structure that sticks up is the crista gallium. It's got to be on a test, it's such a cool word, right? It's attachment of a membrane that separates the brain on the inside between left and right. It's known as the Falk's cerebri.

You don't need to know that word. We'll talk about that later when we get to the next stuff. But it's an attachment of like a membrane and when I say membrane it's like a leathery thick tendon, strong thing. We'll look at that when we get to the brain. And right around that thing coming up here, there's little holes that you can't really see on the skull because it's not real holes.

But when you look in the bone, there are real holes in there. And that's where the nerves go through from the nose into the... the brain that makes us smell the olfactory nerve olfaction is smelling and that's the crib reform plate crib reform means little holes olfactory nerve enters the skull so that's where the smelling nerves goes into the head that's a cool moment And look at that, that brings me to the face. Maxilla, upper jawbone, that's the keystone bone in the face. It's not as, well it's still important, I mean, but in the skull it's really important because of the...

precautions but every other facial bone is touching it except the mandible so the maxilla here the opportunity that matters I'm a medicals in the nasal bone in the lacrimal everybody else attaches to that So that's what that means, keystone bone. And so we have, well, we also have a part of the bone that then goes right to the cheekbone, the zygomatic bone, and they call that the zygomatic process again. It's a different bone now, but we have a zygomatic process now in the temporal bone and on the maxilla. And then we have T-stockets.

They call that alveolar margins. And we have, so that's just the term, you have this little teeth going. That's just for that part.

So all of these, I hope they don't look like that on us. And then we got the palatine process, and the palatine process is the roof of the mouth. You say process, it's a...

I don't know. Yeah, I don't know. Because when I was reading the text, it said, like, I was looking for certain bones, I couldn't remember if those were bones. Well, that's interesting because the palatine process is the roof of the mouth.

But if you take your skull thing and you look on the roof of the mouth, and you go all the way to the back, there's a little line that goes across. About a third towards the back. That's a suture. for then that bone so there is a process and there is a bone so the palatine process is on the mandible the roof of the mouth all the way back don't go all you might make a joke although that then there's an all its own bone and that's then the back of the roof of the mouth bone the back of the roof of the mouth bone is the palatine bone Yeah, I... Palatine bone, that's interesting.

Yeah, you can see it here. See the purple? And then the green?

Can you see that far? The purple is the maxilla, the green is the palatine bone. That'll be around. That's all we need to know about that. And then the lacrimal, we already talked about the lacrimal, is where the tears go down and drain into the nose, the nasal cavity.

And the nasal isn't on the nose. You want me to attack that on the test. That's an easy one.

although that is like is it this or is it that so that that i'm not saying that's on the test but the zygomatic bone that's the cheekbone and then um that's really all we need to know about that as a labeling but also what's interesting what's funny is the zygomatic bone has a temporal process so now you have a temporal process on the zygomatic bone and the zygomatic process on the temple bone so you can start going crazy in the head so don't go too crazy But what's cool is, you know, you can see here, you have bone attached to bone very often. The process that reaches to the bone has the name of the other bone on it, so it's self-explanatory as well. So that's how you want to look at that material. So it's not just memorizing. It's versus sensibility.

Why would that be? Some stuff makes sense, some doesn't, but at least you want to differentiate what doesn't and then just study that. And the stuff you kind of know intuitively, you kind of go with the flow with it. Well that's another thing when you see that information is like what makes sense what doesn't make sense.

If it's already making sense to me it's an easy way to study it I put it in a different department a little bit. If it doesn't make sense I have to first understand it. That's the conscious, the determinants. so when we breathe in the air slows down and it has to turn around and warm up and get some moisture in it and then we can breathe in the lungs and that's how they look on the bottom see that's the ones at the bottom they're really cool bones that's where you put the balloon in And the vulva bone just means plow.

We already just shown it. It's not a bigger deal than that for us. And that brings me to the mandible and that's the lower jaw bone.

Makes it very important in chewing when you close the jaw. we have a few parts of that that we want to know we have a mandibular condyle so now look at this this is funny so you got this ball so here this is clear right this is where the teeth are in but then you got the sidebar here they call the sidebar the ramus I don't need to worry about the alveolar margin, that's a two-socket, so we got that. And then they have this back portion here that makes the joint with the temporal bone, and that's the mandibular condyle. See the word condyle?

Makes a joint. Two bones come together, make a joint. And then we have this thing in the front here, in front of the condyle that makes the joint, and that's known as the coronary.

process and yes you get to say it's annoying that name is hard so the calm dial is here right before in front of the ear where the ear canal is you can feel it when you open close it moves and then in front behind sort of behind the cheekbone this is the cheekbone behind it is is that other part of body you can't palpate it but what happens there is that muscle from here that temporalis the comes down, goes right to that part, and anchors into here, and pulls that jaw closed that way when you chew. So that's a muscle attachment. Coronoid prosthesis is for the temporalis muscle.

Temporalis muscle, and that's gonna be Monday. And then the only other thing here, we got the body, and the body is just the bar in the front. This is the most complicated joint in the body. Reason why? You're got two of them and it's the same bone you're gonna get something off both of them are so it's really tough to balance these ones out and I I don't think I I really know what to do but then I have an ENT walk into the office once it's like how did you treat TMJ's I said yeah I do what do you do is that balance out the motion I say what do you do he says I diagnose it like oh that's great treatment that's you know but that's one of those things it's really hard to deal with the TMJ stuff so if you know somebody with TMJ problems talk to me maybe there's some things we can help just in talking about it by massaging and stuff like that Sometimes you take a finger in and you go in between the teeth and the jaw, that's really helpful too.

Okay, and then the hyoid is just the one down here, a few muscle attachments. I don't think it's much for us, more than that. There's a part pieces to it, but we're not worried about it. Helps the swallowing.

And then that's it.