the human ankle is pretty amazing not only does it support the entire weight of the body it's also incredibly complex and capable of a wide range of movements so we're going to break this down piece by piece we'll look at every bone in the foot all of the joints of the foot and the ankle and then we'll focus in on the ankle joint or the Tallow cural joint specifically we'll look at the main ligaments that give structure to that joint as well as the primary muscles that cause the different movements of the ankle throughout the video we'll look at real human cavers and other cadaveric images provided by anatomage the maker of the world's first life-size virtual dissection table so you can see how all of these structures are arranged three-dimensionally in the body and at the end of the video I'll have some blank diagrams for you to practice because when it comes to learning the ankle joint I want to make sure you get off on the right foot let's jump to the Whiteboard and get started let's start with the bones of the foot in the ankle and we've got two different views here we have a frontal view and a lateral View and of course we're not going to start with all the bones on there at once so let's get rid of those and do those one at a time the first bone we're going to look at is the tibia and the tibia is going to be the main bone giving structure to the lower leg and of course we have the second bone there the fibula so the tibia and fibula are the bones of the lower leg and those are going to articulate directly with the tarsel bones now there's seven tarsel bones and we've got a pneumonic for helping us remember those and that pneumonic is tiger cubs need milk so as we go through these tarsel bones keep in mind that pneumonic and use that as a way to remember these as we go through them so the first one that's going to articulate directly with the tibia and the fibula is the Talis bone I always immediately think of the Stone Talis monsters from The Legend of Zelda games um and this looks just like the stone Talis I think they just took this and copied straight from it probably and this connection between the tibia and the Talis bone is going to form the tibio talor joint also known as the Tallow cural joint or as we often call it just the ankle joint we'll talk more about that a little bit later in the video next we have the calanus the calcinus is your heel bone it's going to articulate directly with the Talis right here forming the sub taler joint which we'll learn more about later on too so Ty Cubs Talis calcinus remember the Talis is going to articulate directly with the tibia and the calcinus is your heel joint which articulates with the Talis now in addition to the tiger cubs need milk pneumonic for remembering this I tend to think of the bones of the foot in two kind of sections we're going to have one section that corresponds with the Talis that's going to be the bones that kind of come off of the Talis in the front here and then the calcinus separately and it's going to have some bones that kind of come off of the calcinus on this side right here that's one way that I categorize these into two different sections to help me remember them so I'll kind of go over that and go in that order as well so the Talis is going to articulate with the navicular bone navicular I think of navigate and when you navigate you usually have multiple directions that you're deciding between and this navicular bone is going to navigate between three different uniform bones so we'll take a look at these three uniform bones next that the navicular bone is navigating between and again I'm just using that navigation metaphor as a way to help it become a little bit more sticky in my my brain help me encode that so I can remember it a little bit better now if we have three uniform bones we have to have ways to distinguish between the three and so we're going to use the directional terms lateral intermediate and medial this is the medial side this is the lateral side so medial intermediate lateral and of course those are going to form the first three letters of milk medial intermediate and lateral I'll draw those over here on my lateral view as well and so here is the lateral uniform bone the intermediate uniform bone and the med uniform bone so when I was learning this I thought of the Talis navicular uniform bones as kind of one group of Bones they're going to articulate with the first second and third metatarsals and then the first second and third sets of fanges in the foot and then separately I've got the calcinus and this next bone right here which is the cuboid bone now when they name this I feel like they they got it wrong because it's not really shaped like a cube in my mind like that's not that's not that I mean you got to really use your imagination to call that a cube but we call it the cuboid bone because somebody thought it was cube-shaped that cuboid bone articulates with the calcinus right here and articulates with the lateral uniform bone as well and that cuboid bone is going to articulate with two different metatarsal bones are metatarsals four and five now take these bones all together and you're going to have the tiger cubs need milk before we go on let's connect that back to our pneumonic tiger cubs need milk tiger is the Talis Cubs is calanus need for navicular and then milk because we've got the medial intermediate and lateral uniform bones and then cuboid so MC for milk now just distal to the tarsel bones we're going to have the metatarsals so let's take a look at the metatarsals next we're going to have five metatarsal bones we're going to number them 1 2 3 four and five so let's add in those numbers right here the big toe is going to correspond with metatarsal 1 and then all the way to the pinky toe is going to correspond with metatarsal five now your metatarsals are not your toe bones but they line up with your five toes now metatarsal number one is going to be called the HX and so that metatarsal along with the fanges there is going to form the hoix if you remember from the hand the thumb was the poock so similar we have a name for this first big toe which is the HX just distal to the metatarsals are going to be the fanges of the foot so the fanges we're going to have three except for on the HX we're just going to have two fanges and if we have multiple of those bones we have to have a different way to distinguish each of those so we're going to have first the proximal fanges and so this would be proximal failinks number one proximal failen number two 3 four and five next we'll have the middle fanges and notice we don't have a middle failen on the HX because the hoex is just going to have two bones that we'll call proximal and distal so we have middle flanges on digits 2 3 4 and five finally we have the distal fanges and we'll have the distal fanges on each of the digits so your hoix or big toe is is going to have one fewer bone than all of the other toes so we've got the tarsals and metatarsals the bones of the foot and then we've got the fanges which are the bones of the toes and here in our cadaveric images from anatomage we have the Talis bone the navicular bone here's the medial intermediate and lateral uniform bones here are the first three metatarsals and then the first three sets of fanges and here we can see the calcinus bone the cuboid bone the fourth and fifth metatarsals and the fourth and fifth sets of fanges so those are all the bones of the foot and the ankle now is probably a good time if you're learning this for the first time uh to pause the video and see if you can name all of those different bones of the foot and the ankle practicing that will help you encode the information a little bit better strategies such as using a pneumonic like tiger cubs need milk or practicing labeling and identifying structures like this or using things like 3D models like the ones from anatomage in this video those are all things that help you encode the information to make it stickier in your brain so you can learn it better in fact if you're learning Anatomy physiology and want to use the best study strategies check out my free a& Survival Guide Link in the description for that all right let's move on to the joints of the foot and the ankle next the first joint we're going to look at is the tibio toor joint or the Tallow cural joint now with most of these joints we're just naming them based on the two bones or types of bones that are forming that joint so tibio toer tibio referring to the tibia talor referring to the Talis we also have this term Tallow cural Tallow for Talis and then crural just means the leg so this is where the Talis is articulating with the rest of the leg when we talk about the ankle joint this is the main joint that we're talking about this is going to be a hinge joint and if you know that hinge joints only have one degree of movement and so this is going to be where we have dorsal flexion and planter flexion dorsa flexion is where the front of the foot moves up like this and planter flexion is where the foot moves down like this the next joint is the tarso metatarsal joint and so that's going to be connecting the tarsel bones with the metat tarsal bones right here those are going to be plain joints plain joints are joints that have smooth flat surfaces that can glide across each other and the tarso metatarso joint isn't going to allow for a lot of movement but it is a sovio joint it is a plain joint next we have the metatarso fangel joints and that's going to be between the metatarsals and the fanges and this is going to be a condid joint condid joints are where one side has a rounded surface kind of a circular is surface and the other bone will have a concave surface and those will fit together to allow a lot of degrees of freedom of movement and think about if you're moving your toes just like moving your fingers you you kind of move those in a lot of different directions like side to side up and down um that condid joint allows for that free movement of the toes and finally we're going to have the interial joints so have proximal interanal joints and distal interanal joints and of course on the hoix we just have one interial joint the interanal joints are hinge joints allowing for just one degree of movement and so think about moving your toe just like moving your finger um you can't really move the this this joint right here or the joints in your toes side to side you really only have this one degree of movement of those joints because they are hinge joints and one other really important joint that we have here is going to be the subt joint that's going to be the joint between the Talis and the calcinus that's going to be another plain joint so two kind of flattish surfaces that slide along each other and that's going to be the main joint that's moving whenever we do inversion and ersion of the foot and so inversion is where we're taking the foot and kind of bending it towards the inside or bending it medially an e verion is when we're taking the foot and bending it the opposite way toward the leral or side of the body later on in the video when we do the muscles we're going to be really looking at the tibio toer joint and that movement of planter flexion and dorsal flexion and then the subtler joint of inversion and ersion movements and I didn't get into all of the inter tarsal joints but all of these articulate with each other so we've got lots of little joints kind of in between the tarsel bones as well but I didn't label those on the diagram up next let's take a look at some of the ligaments of the ankle joint specifically the ligaments of the Tallow curl joint so let's start with the lateral view here first let's look at a group of ligaments that are collectively called the lateral collateral ligament of the ankle these are all going to be working to stabilize the Tallow curl joint and so that's going to be like the tibia the fibula and the Talis stabilizing that complex right there the first is the anterior talofibular ligament and just like the joints the ligaments we're just naming them after the bones involved and so this is going to be the talofibular because it's connecting the Talis to the fibula it's the anterior one cuz it's on the anterior side and that implies the existence of a posterior one so next we have the posterior talofibular ligament the anterior is going to prevent the Talis from moving anteriorly and the posterior talofibular ligament will prevent the Talis from moving posteriorly and the third one then is the calcano fibular ligament and that's going to connect the fibula to the calcus note when you're naming these you always have fibula on the end which is going to be opposite we'll see of the tibia where you have tibia at the beginning of the word so the lateral collateral ligament is made of the anterior and posterior talofibular ligaments as well as the calcano fibular ligament now let's take a look at the medial side the medial side is going to have its own collateral ligament a group of ligaments that we'll call the medial collateral ligament or also the deltoid ligament those are both names for these four ligaments that combine to stabilize this joint the first three kind of mirror the lateral collateral ligament first we're going to have the anterior tibio to ligament that's going to connect the Talis to the tibia of course then we must have the posterior tibio talor ligament connecting the Talis to the tibia on the posterior side and just like the lateral collateral ligament we're going to have one between the tibia and the calcinus so we'll call that the tibio calcal ligament now unlike the lateral side we've got one additional ligament that we're going to add to the medial clal ligament and that's going to be the tibio navicular ligament which is going to connect the navicular bone right here to the tibia so stabilizing the talloc cural joint on the medial side we've got that medial collateral ligament also known as the deltoid ligament and it's made of the anterior and posterior tibio Toler ligaments the tibio calcal ligament and then the tibio navicular ligament I have two more ligaments I want to include on here and these are going to help stabilize the tibia and the fibula together so of course those are going to be called the tibiofibular ligaments so we have an anterior tibio fibular ligament as well as a posterior tibio fibular ligament so here in our cadaveric images from anatomage we can see the posterior and anterior talofibular ligaments as well as the calcano fibular ligament and those make up the lateral collateral ligament on our medial side we can see the anterior and posterior tibiotalar ligaments the tibio calcal ligament and the tibio navicular ligament that all make up the medialateral ligament or the deltoid ligament and here we can see the two ligaments stabilizing the tibia and fibula which are the anterior tibio fibular ligament and the posterior tibio ligament also those of you watching at home I had so many outakes trying to say things like tibio fibular and talofibular so if you have trouble pronouncing these so do I we got an anterior tibio and we have an anterior tibio fig tibio fig try that again so those are the ligaments of the Tallow curl joint now let's look at the muscles of the ankle joint and before we go into those muscles let's review those four movements first we have planter flexion and that's going to be when the front of the foot points down like this towards the planter or the inferior part of the foot and then we have dorsal flexion where the foot is going to move up towards the dorsal surface of the foot like this those will be movements of the tibio toer joint the other two movements that we want to make sure that we know are going to be inversion and ersion so in inversion we're going to be rotating the foot towards the medial side like this and that the primary joint they're moving is the subtler joint and then we have ersion where we're rotating the foot towards the lateral side of the body so all of the muscles we're about to go over going to correspond with one of those four movements and that's how I'm going to categorize them in the video and hopefully that'll help you remember these muscles better as well by categorizing them based on movements categorization is one of my favorite en coding strategies when I'm learning new information like this so let's start on the medial side of the foot and the first muscle we're going to learn is the gastrus the gastrus is actually named after stomach because somebody saw the main body of the muscle and said that it looked like a stomach so they called it gastro most of the muscle is kind of up off of the diagram here and the gastrus is connected to the calcus via the calcal tendon calcal tendon is also known as the Achilles tendon so if you're familiar with the mythology story of Achilles where his mother held him by the ankle and dipped him into the water that protected his body the one place that didn't get protected was the calcal tendon or the Achilles tendon because that's where she was holding him the gastrus is going to be involved in planter flexion it does plant Reflection by pulling up on the calcinus if it pulls up on the calcinus that's going to rotate the rest or the front of the foot downward in the planter direction or the inferior Direction so it pulls up on the calcinus making the rest of the foot Point downward another muscle involved in planter flexion is the Solus muscle this one is also connected via the calcal tendon to the calcus so gastrus Solus both connected via the calcal tendon and causing plant flexion and the third muscle we look at here is the plantaris muscle in the diagram all you can see of the plantaris muscle is the tendon itself cuz the actual body of the plantaris muscle is really really high up really Superior on the leg all three of these muscles have their insertion on the calcinus the gastrus and the plantaris actually have an origin all the way up on the femur the distal end of the femur whereas the Solus has its origin on the proximal end of the tibia and all three will contract to pull the calcinus up causing planter flexion so those are the primary planter flexor muscles here's a list of some other muscles that help with planter Flex as well but the three that we've gone over they're the main ones causing most of the force of the planter flexion movement now the opposite of planter flexion is dorsiflexion and this next muscle the tibialis anterior is going to be the primary dorsa flexor of the foot the tibialis anterior is on the anterior side of the tibia and it actually has an origin on the lateral surface of the tibia on the proximal end of the tibia and that muscle and tendon are going to extend all the way down to right here where it has an insertion on the first metatarsal as well as the medial uniform bone and when that tibialis interior contracts it's going to pull the front part of the foot upward causing dorsal flexion here are some other support muscles that help with dorsal flexion but the Tibi anterior is going to be the primary dorsal flexor of the foot The Next Movement we're going to look at is inversion and for inversion of the ankle it's going to involve the tibialis anterior as well as the tibialis posterior muscle now for inversion and ersion one way to remember what muscles do those two movements um is really easy you just remember that the tibialis muscles the two muscles with tibialis in the name anterior and posterior those are involved in inversion and then in a minute we'll see that the muscles that have fibularis in the name those are involved in ersion because they're going to be on the lateral side now the tibialis posterior is going to have an origin on the tibia that's going to be the part of the tibia that's more Superior or proximal and it's going to be on the posterior surface of that tibia and its insertion down here is going to be on a lot of different bones it's going to be on the navicular bone the uniform bones all three of them as well as some of the metatarsal bones so this tendon right here it kind of spays out and connects to a lot of different Bones on the inferior part of the foot and when those tibialis muscles contract at the same time they're going to both be pulling on this medial side of the foot causing inversion of the foot so quick recap of all these muscles on the medial side the gastronomia Solus and plantaris muscles will do planter flexion the tibialis anterior will do dors AFF flexion and the tibialis anterior and posterior together will cause inversion now let's jump over to the lateral view of our foot and look at the fibularis muscle these three muscles are going to be involved in E version of the foot and the first one is going to be the fibularis brevis muscle the fibularis brevis will have its origin on the fibula and then its insertion is going to be on the fifth metatarsal right here if we have a breous muscle meaning short it must have a longest muscle meaning long so we've got the fibularis longus muscle right here it will also have an origin on the fibula and then its insertion will be down here and we've got a third fibularis muscle and so they just decided to name it the third fibularis muscle and they called it fibularis terus meaning the third its origin of course is on the fibula and its insertion is down here on the fifth metatarsal now you can imagine if all three of these muscles are Contracting they're going to be pulling up on this lateral surface of the foot causing that ersion motion that we've been talking about so remember the tibialis muscles causing inversion and the fibularis muscles causing version and here in our cadaveric images from anatomage we can see those muscles that we've been talking about here we have the gastrus Solus and plantaris muscles here we have the tibialis anterior and then the tibialis posterior and here on the lateral side we have the fibularis longus and the fibularis brevis muscles the only way to make sure that you know that really well is to practice retrieval so I'm going to give you a few blank diagrams take a moment pause the video see if you can name all of the bones of the foot and the ankle and then here are the answers to those up next see if you can name all of the joints of the foot and the ankle and there are all the joints now pause the video see if you can name all the ligaments that are stabilizing the ankle joint and here are all of those ligaments all right next we have the muscles pause the video see if you can name all the muscles on the medial side of the ankle and see if you can name all the Motions that they do here are those muscles and finally let's take a look at the muscles on the lateral side pause the video see if you can name those three muscles as well as the function that they do and here are those muscles hopefully you learned a lot about the ankle special thanks to anatomage um check out their Link in the description below my favorite thing about anatomage is that they use actual scans of human cadavers so when you're looking at the anatomy in anatomage you're you're not just looking at an ideal image of it you're looking at what it actually looked like in somebody's body they've got multiple cavers so you can compare diseases and all that kind of stuff so check that out in the link in the description below if you want to know more about them special thanks to my patrons on patreon thank you all so much for supporting the channel if you're interested in joining the CT science patreon I have blank diagrams from all my videos available on the patreon to all tiers of subscribers and like I said before if you want to make sure you're using all the best strategies to learn a& check out my free A&P survival guide and if you want to learn more about the joints in the body check out this playlist of videos to learn more about those thank you so much for watching and I'll see you in the next video all right bye-bye