Overview of Lower Extremity Skeleton

We are going to review the skeletal system but lower extremity in this video. What lower extremity means is basically your thigh and your leg and your pelvis. All righty, so we're gonna start with the most superior part of your lower extremity, which is the pelvis. Now I'm going to do basically an variation of an anterior view of the pelvis. I'm actually gonna call it an anterosuperior view because it's like we're looking at the front, but we're also looking at it a bit above just so we can get a better view of something so it's kind of a combination between an anterior view and a superior view so that's what i'll write here and tarot superior view And again, feel free to pause this video and fast forward to when I'm done drawing everything or follow along with me. So we're going to start with a piece in the middle. That's our central piece of our pelvis and then I'm going to draw all the others around it. Alright, so that's most of our pelvis. So, let's get to labeling some things. So, first things first. Half of our pelvis. So, our pelvis is this part where my hands are covering. Your sacrum is this part in the middle. Now, we're going to label that in a moment. Before we get going, just one half of your pelvis, this area right here, is called an innominate. So I'm going to write that down. Half of a pelvis is called an innominate. Alrighty, so let's start by labeling. the different bones of the pelvis. Now remember the pelvis is both of these pieces and we're actually going to take this one innominate or half of a pelvis and it's going to be split up into three different pieces. Okay so our first piece of it is This whole area right here and the cutoff point for it is about right there So this is called our ilium And it is, like I said, one of the three bones of the pelvis. Now we're actually going to draw the pelvis in a different view so you'll be able to see the pelvis from that perspective as well. you know the thing about the pelvis is that it's a wonky bone like it's just weirdly shaped and it um it's kind of confusing when you're looking at it so make sure you pay close attention When you're looking at the models. I'm only going to do one half of this. Because on the other half we're going to label a few other things. But anyway. So that is our first part of the innominate. Which is called the ilium. The next bone is called the pubic bone. And the cut off from there is about. Right here. So this is our pubic bone. You may, um, I mean, you've probably heard the term like pubic hair. So that's where that gets its name from is this pubic bone. And it's called the pubis. Now our last piece of this ilium, which again is the same on both sides, but we're just coloring one side for now. That is our ischium. And that's going to be all of this. So those are our main three parts of one part of the ilium. Now, on the other side, what I'm going to do is I'm going to kind of just mark off where our pubic bone borders are, but I'm going to use gray. So it's going to be right here and right there. Now for this pubis or pubic bone right there, it is split up into two different parts. So that's what I'm going to draw on here. So the first part is this thing right here. It's our superior pubic ramus. So basically just the superior part of the pubis. Oops, I got cut off a little bit there. It's R-A-M-U-S. I'll draw it a little bit clearer in the next one. And as you probably guessed, if we have a superior pubic ramus, what else are we going to have? That's right, we're going to have an inferior pubic ramus. So that's going to be here. Just the inferior part of the pubis. R-A-N-U-S. There we go. Now that's clear. Okay. So next let's label one aspect of the ileum right here. And that is actually to be called our iliac crest so I'm just gonna draw where that is and this nice maroon color it's gonna be this whole crescent shaped part of the ilium that's our iliac crest now I'll On the ilium, we also have two other important pieces. The first one is our, we call it our ASIS right here. And our second one is our AIIS. And I'll write down what those are, like what that means in a moment. Let me just, I'm gonna... Put a little blue dot there. It's not actually a dot, it's like a little point on the model, but it's hard to see in the sharpie there. So I'm going to put two little dots right there in this blue color. So the, we have A S I S, which is anterior superior iliac. Spine. And whenever we're talking about spines in the pelvis, it really just means like a little pointy part. So here's our ASIS. And then we also have an AIIS, which is anterior inferior iliac spine. So that's why these acronyms are the way they are. Essentially, it just takes too long to say these things. So we talk about it as ASIS is the superior one. AIIS is the inferior one. And remember, it's the same thing on both sides, but I just wanted to be able to divide things up for us in this way. Now, we also have a sacrum. So our sacrum is... This structure right here. Remember we talked about it as being right in the center. So it's this nice deep teal color is our sacrum. Now within that, we have a few different things to label, and I actually forgot to put a couple of these in. There are some holes that should have been in there. Those are called our sacral foramen. Remember we always talk about foramen as holes and they're not quite lined up properly. That was my bad. They're a little bit off but you know that's the fun of drawing. So those are our sacral foramen which is the holes where our sacral nerve roots come out and we're actually gonna get to our neurological section shortly after this after we finish muscles so we'll learn more about those nerves then now the other part we have on our sacrum is right here these are like the little wings of the sacrum And they are our sacral ala. And ala actually means wing. So it's like this outer portion of the sacrum right there. Almost like the little wing looking structures at the top. And one more thing I want to point out here is our, the joint between the sacrum and the ilium. That's called our sacroiliac joint. So for that, I'm actually, let's see, what should I do? I'm going to make that like a deep purple color. So it's going to be this joint right here. It's kind of hard to see because it looks kind of the same as the block. But it's the joint right where my pen is in between the ilium and the sacrum. And that is our sacroiliac joint. Sometimes known as the SIJ or SI joint. Alrighty, now I want to also label this little structure down here at the bottom. Let's see. At the bottom we have our coccyx, which is also known as our tailbone. Then we have something else that I want to label that's actually kind of poking out from behind that I forgot to draw but it's kind of poking out like that. You can see it a little bit more posteriorly but that is actually part of that's part of our issue. I'm going to put a little bit of orange there just so we can see as a little reminder. But more specifically there, we have something called our ischial spine. So I'm going to put a little circle right here. That's where our ischial spine is. And remember, a spine, when we talk about the pelvis, is just like the little pointy part sticking out. Next, we have something that connects these two parts of the pelvis or these two innominates in the front. So in the back, we have the sacrum and the SI joint. But in the front, we have something called your pubic symphysis. So let's make that. I'm running low on colors here. Let's make that brown, I guess. Actually, you know what? I lied. I'm going to make it this nice little peach color. There we go. That is our pubic symphysis. And that is actually made of the same material or like tissue that the discs in your spine are made of in between each vertebrae. Now let's see what else do we have to label. Oh, I want to label our iliac fossa. Which I'm just going to put a circle here where that fossa is. And I'm just going to make it striped so we can still see that that's our ilium underneath. That is our iliac fossa. Oops, I-L-I-A-C fossa. And then we have our acetabulum, which is this little circle right here. That's where our femur, which is our thigh bone, connects to our pelvis. And this acetabulum combined with the head of our femur or thigh bone that we're going to learn about in a moment forms our hip joint. Let's see, I think we have... One more thing to label, and that is our obturator for Raymond. So let's see. I'm so low on colors here, man. Oh, let's use a nice blue. So our obturator for Raymond. Again, for Freeman, I'm going to try to just color like the outside so we can see that it actually is a hole. But it's this nice blue thing, and I'll do it on both sides. So we can see it. And here we have two muscles, our obturator internus and obturator externus. Don't worry about that. We'll learn that later. But I'm going to label that obturator foramen. And as you know, a foramen is just a hole that something can travel through. So I think that does it for our pelvis. What I'm going to do is I'm actually just going to draw two femurs there because I want us to be able to understand how this acetabulum in our pelvis as a whole fits in with our other bones. So I'm actually just going to draw a few little femurs here on the side because this is right where it forms a joint. There we go. So there's one little femur just so we can tell to remind ourselves. Um and I'm going to make that, I'll make it gray. which is a little boring but i'm just gonna color this guy in so again not part of the pelvis but it fits in as you can see like it's actually called a ball and socket joint because this like ball type head of the femur or your thigh bone fits right into that little socket in the pelvis I think that's all that I want to show you in this view. What I'm going to do here is I'm actually going to draw one more view of the pelvis because I want you to see how these three main pieces of an innominate look from a different perspective. So let me add that in. I'm just gonna draw down here. So this is going to be a lateral view. And bear with me, this is super funky to draw. So I'm gonna take my time a little bit and attempt to not mess this up. I'm almost done. Hang in there with me. This doesn't have to be perfect because mine isn't for sure. Anyway, this is what the lateral view of one innominate looks like. So for reference, this is our acetabulum right here where I'm drawing my lines. It's actually going to be split into three different parts, but so we remember that it's our acetabulum. I'm going to just draw. A circle around it right here. And then what I'm going to do is I'm going to label our three different bones. So our first one is our ilium, which is this guy right here. Our ilium is always going to be our biggest, like widest bone. So if you kind of need a way to remember that, always locate your ilium first. It's going to be the one with this big iliac crest on it as well. And the acetabulum is actually going to be split into three different parts where all the bones come together. So this part of the limb is going to be the acetabulum. And then we're also going to have the pubis, which is this part right here. And it's going to be split right there. So this is going to make more sense when you're looking at the models or pictures in your textbook so make sure that you're looking at that here. I just want to give you a different view since this is so the shape of it is so funky. And then lastly we have our ischium which is gonna take up like this third of our acetabulum and this bottom part right here. Alrighty, sweet. So now that we have this, you know, here are most of our, the parts of our pelvis, but I'm going to add in one extra view just to show you a few different things that we couldn't see on the front of the pelvis. So we're still looking at our pelvis, but here we're going to have a posterior view. There's not a whole ton that I'm gonna label in here because you'll be able to see the same things on the back that you saw On the front and it'll make sense when you're looking at it But I do just want to add in a few more little landmarks All right. So whenever you're drawing a sacrum kind of starting at the middle is a little bit easier So that's what I'm gonna do I'm drawing the middle part right now and I'm always attempting to make these as symmetrical as I can but they're not always symmetrical so you try your best and together we'll figure it out Alright, so in between we have our sacrum right here. And then we're gonna have our coccyx right there. Almost done here. Hang in there with me. Sweet, we did it. Okay, so here's our posterior view of our pelvis. We're gonna label a couple of things. I'm gonna try to keep the same colors as I did before, just so we know where we're at. But before I forget, um, actually, you know what? Yeah, let's label things first. So we have our sacrum. which is right here it's kind of covered right here by pieces of the ilium so i'm just gonna do a little border like this i drew your sacrum here a little bit too wide so just make note of that it should be a little bit more narrow so that's our sacrum And then we also have our coccyx, which is this guy down here. Remember, that's your tailbone. Now, you know, when we're looking at our pelvis, it's really important to note that this is the base of our spine, essentially. So your sacrum forms a joint with your spine right here in your fifth lumbar vertebrae. And that's really important, right? Because this is our base of our spine. If we have, if things are like thrown off in our pelvis, what we can do to kind of determine if one in nominate is either like. like rotated or shifted or anything, um, how I kind of look at it as a physical therapist is I'll, um, put my hands on someone's pelvis. Okay. And I'll put my hands on the side of it. And my thumbs will be on, um, their anterior superior iliac spines. So to bring this picture back in, they'll be like right here on someone's pelvis. And I'll be able to tell if it's if it's shifted up or down or if it's nice and symmetrical. And then what I can do is I can also put my hands on other landmarks in the back here and see if those are shifted up and down. And that will tell me if their pelvis is out of alignment and that can cause a lot of pain and discomfort in a few different areas. So that's why this is so important is like for me as a physical therapist, I'm actually going in and I'm palpating or I'm touching these. different bony landmarks. I have to be able to know my anatomy to locate them properly to see if someone's pelvis is out of alignment. Okay. Now, um, the same thing can actually happen with your coccyx, your tailbone. You can actually like fall on your tailbone and it can, um, cause harm at this joint between the, excuse me, between the coccyx and the same. And what sits directly anteriorly to your coccyx actually is your rectum. So that can cause a lot of issues with bowel movements and everything as well. So that's why we're learning this anatomy is because we want to be able to use it clinically for most of us. And knowing these bony landmarks will help us determine if our patients... have any alignment issues or any dysfunction there. It can help us really make sure we're treating them properly. So, all right, is there anything else I want to label here? Yes, I want to label our ischial spine, which is what I actually labeled on the anterior view, anterior superior view. Remember, that's right here, our ischial spine. It's part of our ischium, kind of poking back posteriorly here, and I'm going to draw. it here as well it's actually right there and right there that's our ischial spine so Not only do we need to know bony landmarks to make sure that we know if someone's pelvis is symmetrical or if there's any damage or anything, but we also need to know because oftentimes landmarks are where muscles attach. In addition to muscles, we actually have a few ligaments that I want you to know. Now, let's see. Before, I'm actually, I'm going to teach you two ligaments, but I want to label one last bony landmark before we go there. And that is actually going to be our ischial tuberosity. So our ischial tuberosity is actually like, whenever we say tuberosity or tubercle, it's a little chunk of bone that's sticking out. So our ischial tuberosity is actually going to be right here on our ischium. And that's also called your sit bones. Oftentimes they use that word in yoga. But if you put your hands on your butt right now and you kind of like wiggle around, you'll be able to feel your ischial tuberosity is kind of poking through right there. Okay. So that's what these are. Ischial tuberosity. Alrighty. So now that we have those two landmarks. What I want us to do is I want us to learn about a few ligaments that attach to those landmarks. And they're pretty important because they can be sources of pain, but they're also sources of stability. So our first ligament that I want us to learn is our sacrospinous ligament. And it goes from our sacrum to our ischial spine. So it's just going to come right across, just like that. Sacrospinous ligament. So remember this is like soft like connective tissue this is not bone but I want to show you two ligaments. Our second ligament is going to be our sacrotuberous ligament which is going to go from the ischial tuberosity which is why it's sacrotuberous. and it's gonna go to the sacrum so that's what's called sacrotuberous and that's gonna go like this sacrotuberous ligament now remember how we had our asis and aiis anteriorly We're going to have something comparable posteriorly. So it's going to be these two little pointy things right here. That's going to be our PSIS or posterior superior iliac spine. Because remember, wherever we see our iliac. crest that's where ilium is and i'm also going to do our piis our posterior superior oops i wrote that wrong It should be inferior. I got in my groove there. I-N-F. Ooh, that's a little messy, but it should be posterior inferior. Iliac spine. Alrighty, so that kind of does it for our posterior pelvis. Make sure you're also referencing the anterior pelvis and our different muscles. And later, what we're going to actually learn about is pelvic floor muscles that actually form a little hand. right here as well. And like what we talked about before, those muscles can actually be affected by what we call pelvic symmetry or pelvic asymmetry, which is remember, I can put my hand, my fingers on someone's PSISs or ASISs and see if one is like shifted superiorly or inferiorly. And that will help me determine if like, if these are two innominates that I'm holding in my hand. It can be rotated forward or backwards and it could be like slipped. So anyway, that's why our pelvis is important. Now what we're going to do is we're going to continue moving inferiorly. Next we're going to move to our femur. So here is our femur. Which remember, as we learned in our first lecture, on our first day, we are going to refer to the femur as our thigh. Oftentimes when people are talking about an entire lower extremity, they'll refer to it as their thigh. their leg, but that's actually incorrect. The upper part is our thigh and the lower part is our leg. Now, as always, let's start by drawing things out. So I'm going to draw two different views. We're going to start with an anterior view. And this is going to be, let's see, this is going to be our right femur. I'll just write that down. Right finger. Just so we know. In case you're looking at the models and you're kind of getting a little mixed up. Alrighty. So in our anterior view. Bear with me again as I draw this guy out. All righty. Oops, I messed up and kind of drew him a little too skinny. Let me make him a little wider. There we go. No one ever knew. All right, our femur bone is pretty long, so I want to show you that. If you're ever getting confused, oftentimes people get confused between arm bones and leg bones. Your femur is the biggest, longest one, okay? Alrighty, that's our anterior view and then while we're at it, let's also draw our posterior view. I'm gonna try to kind of make these match up, but we'll see how it goes. Alright, we got our femur nice and big and long. Sweet. Okay, there's our poster review. Now we get to the fun. all of the labeling alrighty what do I want you to know so let's start with let's start with the head of the femur the head is this ball actually it should look like a little more like a ball type structure I didn't do too gray there there we go now that looks like more of a ball right Alright, remember we have the head of our humerus as well and the head of the radius. So a lot of bones have these same type of names. Alright, I'm gonna write these at the bottom. Head. Then we also have a neck. Remember we have a neck of the humerus and neck of the radius as well. Thank Alright, then we have our greater and lesser trochanter. Remember we had our greater tubercle before and lesser tubercle on the humerus? Well, here we have a trochanter. So, let's label those. Let's see, let's do our greater trochanter right here. It's going to be this big piece. Tear, tear. Alright, and if we have a greater trochanter, what else are we going to have? That's right, we're going to have a lesser trochanter. It's going to be right here. And it's just smaller, that's why it's called lesser trochanter. Alrighty. Now, what else do I want you to know? I think that's pretty much it, superiorly. You're going to have something on the posterior side of the humerus, and it's just going to be this line kind of going down the center, and that's just going to be called your linea aspera, and that is a place where some muscles will attach. Actually, your hamstrings, which is on your posterior thigh. Alrighty, now we're going to jump to the inferior part of the femur. And remember how in the humerus we talked about epicondyles and then technically... something that we call, we have different names for, but they're technically our condyle. Well, here we're actually going to have something that we do actually refer to as condyles, as opposed to the humorous where we had different names. for them. So we're going to have a medial and lateral condyle. So let's actually, you know what, I forgot to write. This is lateral. This is medial. The head of the femur is going to be facing medially. So we have our Medial and lateral calm down. Now, what did we have above the condyle when we're looking at the humerus? We had medial and lateral epicondyle. So let's label those here because we actually have the same thing. Right here. right here and then anteriorly we can only see the epicondyles we can't see the condyle so it's gonna be right here and here epicondyle epi means above just as a little reminder And then something else we're going to have on the posterior side is something that we call the intercondylar fossa. That's going to be right here. It's just going to be a fossa, so like a shallow depression. And it's going to be in between the contiles, which is why it's called the intercondylar fossa. Now, one other thing that I want to include here is you'll see like a little surface right here on the anterior femur. And that's going to be nice and smooth because that's where our patella or kneecap will sit. Okay. So, what I'll do is I'll actually draw that out in our next drawing and we'll draw out the end of the femur with the patella or the kneecap sitting there. And then we're also going to draw the tibia and fibula, which are our leg bones. So here we're going to talk about our tibia, fibula, and patella. For these there aren't quite as many structures as there were for the femur so we're just going to draw things out anteriorly because posteriorly there's not really a whole lot of things that we need to locate so we're going to draw an anterior view. So let's start with the distal end of the femur. We have our epicondyle coming down. Alright, so that's our femur. And then we have a little surface here for our patella. So your patella is your kneecap. So that's actually going to be sitting over it. Kind of like that. Um, and then what I'm going to do as I've done for other joints is I'm going to draw the tibia and the fibula, but normally it'll be sitting right underneath the femur, but I'm going to draw it a little bit separated just so we can see, um, like the joint surfaces basically. So let's start with the, this is going to be, right structure because this is going to be lateral and medial. Alrighty, so our tibia is the one that actually like articulates or forms a little joint surface with our femur so it's gonna look like that. Alright, so that's our tibia and then our fibula is actually going to be squished right next to it. Right here. And this should actually be a little bit wider. And then we're going to have part of our femula coming down just like that. Okay? So this is our anterior view. Now, what do I want you to know? So let's label our patella first. Our kneecap, remember that's sitting anteriorly to our femur, but I'm just drawing our femur behind so we can kind of see, almost like we have x-ray vision, we're looking through the patella to see what the femur looks like there as well. So let's label it patella, and then I'll also label our femur posteriorly. Let me get pink. And I messed up and I actually drew the femur a little bit small compared to the size of the tibia right here. So just keep that in mind. That our femur, the distal end of the femur is going to be kind of like just about the same size as the superior part of the tibia. Maybe a little bit bigger. So that's our femur. And what's... interesting is a lot of times people will have knee pain and they actually go through the process of getting a joint replacement because on their x-rays um you'll see that like the the cartilage has worn down on the knees and there is a little bit bit of damage to the bone, but actually what people don't realize is what causes a lot of the pain oftentimes is the patella itself rather than the knee joint, which is the joint between the femur and the tibia right here. So that's something that we really have to pay attention to if you enter a field like physical therapy or if you're a physician or physician assistant or nurse and you're dealing with someone with knee pain, oftentimes it's important to have them assessed by. a physical therapist and have them look at their patella to make sure that's not the source of the knee pain. Because imagine going through a huge joint replacement, which is a really big surgery, and then finding out that it was actually your patella that was causing the pain, even though you happen to have some breakdown on the surface of your actual knee joint. Alrighty, so we're going to have condyles here as well. We have a lot of condyles in the body, so we're going to have medial and lateral condyles. condylus here on the tibia. So it's going to be right here and right here. Medial and lateral Actually, you know what? What I forgot to do before I started was label which one is the tibia and which one is the fibula. So let's do that first. tibia fibula you know which one is first because well i remember it is the fibula has an l in it so we know that that is our fibula because there's an l and l is what lateral begins with um you can also remember it because the fibula is really skinny and off to the side and that kind of looks like an l as well um or just come up with your own way of remembering it so anyway that's our our tibia. Those are our common dials. Let's see. Then we also have something called our tibial tuberosity. And that is going to be right here. And we're going to have some pretty important ligamentous and some would say like muscular, but basically you're just going to have attachments there that come from your quadricep and your patella. Oftentimes because of those soft tissue ligamentous attachments on that tibial tuberosity, it's pretty common for individuals to have pain there, especially as they're growing. There's something called... Osgood slaughters, which is a condition where people have pain at that location. So, you know, all of this anatomy is clinically relevant. Now let's see. Oh, the other thing that I missed here that I want to label is our... Our lateral malleolus and our medial malleolus. So the medial one is the one on the tibia and the lateral one is the one on the fibula. Oftentimes people will fracture those little parts sticking down the malleoli of the tibia and the fibula and they'll say like, oh, I sprained my ankle. Oftentimes it's actually not their ankle itself. It's a fracture of their tibia or their fibula. Alrighty. So one or actually two last things. We, just like in other strokes. we have a head and neck. We're also going to have a head and neck of the fibula. So our head is always going to be up at the top here. That's our head of the fibula. And then we'll also have our neck. Right there. Alrighty, so that covers our leg. So we jump back up to the femur, covered our patella, and then we covered all of these landmarks in our leg. Now what we're going to do is we're going to move to the foot. Alrighty, let's draw a foot. That's the last part of our lower extremity. We're going to draw a superior view. And this is going to be a right foot, just for reference, if you're looking at the models and get a little confused. Alrighty, so let's start with... We're going to start at the, so remember this is a superior view. We're looking down on the foot. So this is as if you're like sitting in your chair right now and you look down at your foot and see the very top of your right foot. So let's start at the bottom here. We're going to draw a few bones. And the foot is another funky one because, you know, we can look at this in a superior view, but we can also look from a different view and it's going to look completely different. So this is just the easiest way for us to identify all of these different foot bones is by starting with a superior view. Alrighty, so we got our main bones right here. These are actually called tarsal bones. Remember how we taught called the wrist bones, carpal bones? Well, all of these are called our tarsal bones. tarsal bones and they're analogous to our wrist bones but these are really like our ankle bones right here so let's get into the other bones that we have remember we had metacarpals well we're also going to have metatarsals in the foot so that's what i'm going to start by drawing out right here so And these don't have to be perfect. We're just trying to get the gist of them. And our fifth one kind of pokes off the side here. Sweet. Now I'm not going to make the same mistake I did in the hand by fusing my bones when I drew them so... Our big toe is kind of like our thumb in that there are only two phalanges. And what's nice is we use the same terms in the foot that we do in the hand for these little toe bones. It's kind of cool to think about all of these little bones just like being inside of our feet and all working together. Almost done. Alrighty, here we go. So now that we have all those out, we are going to label them. So what I'm going to do is I want to, let's see, I'm going to just write a little sign here because I want us to remember that these are our tarsal bones. Alrighty, so for our tarsal bones, we have our talus. That's this one right here. Then right next to that and actually like below it so like more inferior on the body what we call the like the heel of our foot is our calcaneus. So we can only see the side of it but there's some of it is hidden underneath the talus. So that's also one of our tarsal bones. These ones in our feet, you know how I said our tarsal bones are analogous to our carpal bones and our wrists? Well our tarsal bones are a lot bigger than those carpal bones. Calcaneus, which is our heel bone right there. Now next we're going to have our navicular right here. Our navicular is really important. You can see if someone has like a low arch where their foot is a little more collapsed, it's something called the navicular drop because it's dropped closer to the ground. Then off to the side right here we have something called our cuboid. This is actually a common place where people will get injured as well or their cuboid will be like displaced a little bit and it'll be like sharp pinpoint pain on the lateral. Oops speaking of which I didn't label lateral and medial like I want to. but there will be pinpoint pain on the plantar surface of their foot right where the cuboid bone is and oftentimes the cuboid bone can kind of be slipped out of place so just mobilizing it back into place can be really helpful to relieve that pain That's our cuboid. Alrighty, then we have a group of three different bones, and they are called the cuneiforms. We got one, two. And three. And so whenever we label anything in the foot, it's always going to be the same thing as the hand. So your big toe is kind of like your thumb. So that's always going to be number one, two, three, four, five. As you can see, like if we follow our big toe down, this leads to number one, this leads to number two, and this leads to number three. So for these cuneiform bones, sometimes they call it lateral or like medial, middle. and lateral but sometimes I'll call it the first second and third so I'll write that down and then I'll just say medial middle and lateral or one two and three Alrighty, so now that we have that covered, let's label. Remember we had our metacarpals in our hand? Well, we're going to have our metatarsals in our foot. That's going to be these big long bones, which is like the bulk of like the body of your foot. And then the phalanges are going to be your toes. So right now I'm coloring in the fourth metatarsal bone. So it's the same way that we kind of like name things in the hand. And this is our fifth metatarsal. Metaparsals. And then same thing as with the hand. That's what's so nice about this is it doesn't really change that much. So I'm even going to use the same colors we did for our hand model. We're gonna have our proximal phalanx, which we're gonna make this nice deep blue. And like I said before, remember that the big toe only has a proximal phalanx and a distal phalanx, but all the other ones have a proximal, middle, and distal phalanx, or those phalanges. So now I'm coloring in the third. proximal phalanx, fourth proximal phalanx, and fifth proximal phalanx. Oops. Proximal phalanx. Remember, plural for phalanx is phalanges. Now let's color in our middle phalanxes or phalanges. And then lastly we got our distal phalanx erythroplasia. Now, I just want to point out a little bit of nomenclature that's going to be important. First of all, oftentimes for metatarsals, you will verbally say it as your first. metatarsal but sometimes um roman numerals will be used and it'll be like metatarsal and roman numeral one etc and then whenever we're talking about the big toe remember how when we're talking about the thumb It's called the pollux or pollicis when we're referring to muscles. For the foot, we're going to have something comparable. And we're referring to the first digit of the foot, which is the big toe. We're going to use the term hallux. Um, so if we're using that term in terms of like muscles, there are muscles with a word halicis in it. So just to make sure that we're on the same page when we start moving forward with other things. Now this wraps up the lower extremity portion of the skeletal system.

So we're going to start with a piece in the middle. That's our central piece of our pelvis and then I'm going to draw all the others around it. Alright, so that's most of our pelvis. So, let's get to labeling some things.

So, first things first. Half of our pelvis. So, our pelvis is this part where my hands are covering. Your sacrum is this part in the middle.

Now, we're going to label that in a moment. Before we get going, just one half of your pelvis, this area right here, is called an innominate. So I'm going to write that down.

Half of a pelvis is called an innominate. Alrighty, so let's start by labeling. the different bones of the pelvis. Now remember the pelvis is both of these pieces and we're actually going to take this one innominate or half of a pelvis and it's going to be split up into three different pieces. Okay so our first piece of it is This whole area right here and the cutoff point for it is about right there So this is called our ilium And it is, like I said, one of the three bones of the pelvis.

Now we're actually going to draw the pelvis in a different view so you'll be able to see the pelvis from that perspective as well. you know the thing about the pelvis is that it's a wonky bone like it's just weirdly shaped and it um it's kind of confusing when you're looking at it so make sure you pay close attention When you're looking at the models. I'm only going to do one half of this.

Because on the other half we're going to label a few other things. But anyway. So that is our first part of the innominate.

Which is called the ilium. The next bone is called the pubic bone. And the cut off from there is about.

Right here. So this is our pubic bone. You may, um, I mean, you've probably heard the term like pubic hair.

So that's where that gets its name from is this pubic bone. And it's called the pubis. Now our last piece of this ilium, which again is the same on both sides, but we're just coloring one side for now. That is our ischium.

And that's going to be all of this. So those are our main three parts of one part of the ilium. Now, on the other side, what I'm going to do is I'm going to kind of just mark off where our pubic bone borders are, but I'm going to use gray. So it's going to be right here and right there. Now for this pubis or pubic bone right there, it is split up into two different parts.

So that's what I'm going to draw on here. So the first part is this thing right here. It's our superior pubic ramus. So basically just the superior part of the pubis. Oops, I got cut off a little bit there.

It's R-A-M-U-S. I'll draw it a little bit clearer in the next one. And as you probably guessed, if we have a superior pubic ramus, what else are we going to have? That's right, we're going to have an inferior pubic ramus.

So that's going to be here. Just the inferior part of the pubis. R-A-N-U-S. There we go. Now that's clear.

Okay. So next let's label one aspect of the ileum right here. And that is actually to be called our iliac crest so I'm just gonna draw where that is and this nice maroon color it's gonna be this whole crescent shaped part of the ilium that's our iliac crest now I'll On the ilium, we also have two other important pieces.

The first one is our, we call it our ASIS right here. And our second one is our AIIS. And I'll write down what those are, like what that means in a moment.

Let me just, I'm gonna... Put a little blue dot there. It's not actually a dot, it's like a little point on the model, but it's hard to see in the sharpie there.

So I'm going to put two little dots right there in this blue color. So the, we have A S I S, which is anterior superior iliac. Spine. And whenever we're talking about spines in the pelvis, it really just means like a little pointy part.

So here's our ASIS. And then we also have an AIIS, which is anterior inferior iliac spine. So that's why these acronyms are the way they are.

Essentially, it just takes too long to say these things. So we talk about it as ASIS is the superior one. AIIS is the inferior one. And remember, it's the same thing on both sides, but I just wanted to be able to divide things up for us in this way. Now, we also have a sacrum.

So our sacrum is... This structure right here. Remember we talked about it as being right in the center.

So it's this nice deep teal color is our sacrum. Now within that, we have a few different things to label, and I actually forgot to put a couple of these in. There are some holes that should have been in there. Those are called our sacral foramen. Remember we always talk about foramen as holes and they're not quite lined up properly.

That was my bad. They're a little bit off but you know that's the fun of drawing. So those are our sacral foramen which is the holes where our sacral nerve roots come out and we're actually gonna get to our neurological section shortly after this after we finish muscles so we'll learn more about those nerves then now the other part we have on our sacrum is right here these are like the little wings of the sacrum And they are our sacral ala.

And ala actually means wing. So it's like this outer portion of the sacrum right there. Almost like the little wing looking structures at the top.

And one more thing I want to point out here is our, the joint between the sacrum and the ilium. That's called our sacroiliac joint. So for that, I'm actually, let's see, what should I do? I'm going to make that like a deep purple color. So it's going to be this joint right here.

It's kind of hard to see because it looks kind of the same as the block. But it's the joint right where my pen is in between the ilium and the sacrum. And that is our sacroiliac joint. Sometimes known as the SIJ or SI joint.

Alrighty, now I want to also label this little structure down here at the bottom. Let's see. At the bottom we have our coccyx, which is also known as our tailbone.

Then we have something else that I want to label that's actually kind of poking out from behind that I forgot to draw but it's kind of poking out like that. You can see it a little bit more posteriorly but that is actually part of that's part of our issue. I'm going to put a little bit of orange there just so we can see as a little reminder. But more specifically there, we have something called our ischial spine. So I'm going to put a little circle right here.

That's where our ischial spine is. And remember, a spine, when we talk about the pelvis, is just like the little pointy part sticking out. Next, we have something that connects these two parts of the pelvis or these two innominates in the front. So in the back, we have the sacrum and the SI joint. But in the front, we have something called your pubic symphysis.

So let's make that. I'm running low on colors here. Let's make that brown, I guess.

Actually, you know what? I lied. I'm going to make it this nice little peach color.

There we go. That is our pubic symphysis. And that is actually made of the same material or like tissue that the discs in your spine are made of in between each vertebrae.

Now let's see what else do we have to label. Oh, I want to label our iliac fossa. Which I'm just going to put a circle here where that fossa is. And I'm just going to make it striped so we can still see that that's our ilium underneath. That is our iliac fossa.

Oops, I-L-I-A-C fossa. And then we have our acetabulum, which is this little circle right here. That's where our femur, which is our thigh bone, connects to our pelvis.

And this acetabulum combined with the head of our femur or thigh bone that we're going to learn about in a moment forms our hip joint. Let's see, I think we have... One more thing to label, and that is our obturator for Raymond.

So let's see. I'm so low on colors here, man. Oh, let's use a nice blue. So our obturator for Raymond.

Again, for Freeman, I'm going to try to just color like the outside so we can see that it actually is a hole. But it's this nice blue thing, and I'll do it on both sides. So we can see it.

And here we have two muscles, our obturator internus and obturator externus. Don't worry about that. We'll learn that later. But I'm going to label that obturator foramen. And as you know, a foramen is just a hole that something can travel through.

So I think that does it for our pelvis. What I'm going to do is I'm actually just going to draw two femurs there because I want us to be able to understand how this acetabulum in our pelvis as a whole fits in with our other bones. So I'm actually just going to draw a few little femurs here on the side because this is right where it forms a joint. There we go. So there's one little femur just so we can tell to remind ourselves.

Um and I'm going to make that, I'll make it gray. which is a little boring but i'm just gonna color this guy in so again not part of the pelvis but it fits in as you can see like it's actually called a ball and socket joint because this like ball type head of the femur or your thigh bone fits right into that little socket in the pelvis I think that's all that I want to show you in this view. What I'm going to do here is I'm actually going to draw one more view of the pelvis because I want you to see how these three main pieces of an innominate look from a different perspective. So let me add that in. I'm just gonna draw down here.

So this is going to be a lateral view. And bear with me, this is super funky to draw. So I'm gonna take my time a little bit and attempt to not mess this up. I'm almost done.

Hang in there with me. This doesn't have to be perfect because mine isn't for sure. Anyway, this is what the lateral view of one innominate looks like. So for reference, this is our acetabulum right here where I'm drawing my lines. It's actually going to be split into three different parts, but so we remember that it's our acetabulum.

I'm going to just draw. A circle around it right here. And then what I'm going to do is I'm going to label our three different bones. So our first one is our ilium, which is this guy right here. Our ilium is always going to be our biggest, like widest bone.

So if you kind of need a way to remember that, always locate your ilium first. It's going to be the one with this big iliac crest on it as well. And the acetabulum is actually going to be split into three different parts where all the bones come together.

So this part of the limb is going to be the acetabulum. And then we're also going to have the pubis, which is this part right here. And it's going to be split right there.

So this is going to make more sense when you're looking at the models or pictures in your textbook so make sure that you're looking at that here. I just want to give you a different view since this is so the shape of it is so funky. And then lastly we have our ischium which is gonna take up like this third of our acetabulum and this bottom part right here.

Alrighty, sweet. So now that we have this, you know, here are most of our, the parts of our pelvis, but I'm going to add in one extra view just to show you a few different things that we couldn't see on the front of the pelvis. So we're still looking at our pelvis, but here we're going to have a posterior view.

There's not a whole ton that I'm gonna label in here because you'll be able to see the same things on the back that you saw On the front and it'll make sense when you're looking at it But I do just want to add in a few more little landmarks All right. So whenever you're drawing a sacrum kind of starting at the middle is a little bit easier So that's what I'm gonna do I'm drawing the middle part right now and I'm always attempting to make these as symmetrical as I can but they're not always symmetrical so you try your best and together we'll figure it out Alright, so in between we have our sacrum right here. And then we're gonna have our coccyx right there.

Almost done here. Hang in there with me. Sweet, we did it. Okay, so here's our posterior view of our pelvis.

We're gonna label a couple of things. I'm gonna try to keep the same colors as I did before, just so we know where we're at. But before I forget, um, actually, you know what?

Yeah, let's label things first. So we have our sacrum. which is right here it's kind of covered right here by pieces of the ilium so i'm just gonna do a little border like this i drew your sacrum here a little bit too wide so just make note of that it should be a little bit more narrow so that's our sacrum And then we also have our coccyx, which is this guy down here. Remember, that's your tailbone. Now, you know, when we're looking at our pelvis, it's really important to note that this is the base of our spine, essentially.

So your sacrum forms a joint with your spine right here in your fifth lumbar vertebrae. And that's really important, right? Because this is our base of our spine. If we have, if things are like thrown off in our pelvis, what we can do to kind of determine if one in nominate is either like. like rotated or shifted or anything, um, how I kind of look at it as a physical therapist is I'll, um, put my hands on someone's pelvis.

Okay. And I'll put my hands on the side of it. And my thumbs will be on, um, their anterior superior iliac spines. So to bring this picture back in, they'll be like right here on someone's pelvis. And I'll be able to tell if it's if it's shifted up or down or if it's nice and symmetrical.

And then what I can do is I can also put my hands on other landmarks in the back here and see if those are shifted up and down. And that will tell me if their pelvis is out of alignment and that can cause a lot of pain and discomfort in a few different areas. So that's why this is so important is like for me as a physical therapist, I'm actually going in and I'm palpating or I'm touching these. different bony landmarks.

I have to be able to know my anatomy to locate them properly to see if someone's pelvis is out of alignment. Okay. Now, um, the same thing can actually happen with your coccyx, your tailbone.

You can actually like fall on your tailbone and it can, um, cause harm at this joint between the, excuse me, between the coccyx and the same. And what sits directly anteriorly to your coccyx actually is your rectum. So that can cause a lot of issues with bowel movements and everything as well.

So that's why we're learning this anatomy is because we want to be able to use it clinically for most of us. And knowing these bony landmarks will help us determine if our patients... have any alignment issues or any dysfunction there. It can help us really make sure we're treating them properly. So, all right, is there anything else I want to label here?

Yes, I want to label our ischial spine, which is what I actually labeled on the anterior view, anterior superior view. Remember, that's right here, our ischial spine. It's part of our ischium, kind of poking back posteriorly here, and I'm going to draw. it here as well it's actually right there and right there that's our ischial spine so Not only do we need to know bony landmarks to make sure that we know if someone's pelvis is symmetrical or if there's any damage or anything, but we also need to know because oftentimes landmarks are where muscles attach.

In addition to muscles, we actually have a few ligaments that I want you to know. Now, let's see. Before, I'm actually, I'm going to teach you two ligaments, but I want to label one last bony landmark before we go there.

And that is actually going to be our ischial tuberosity. So our ischial tuberosity is actually like, whenever we say tuberosity or tubercle, it's a little chunk of bone that's sticking out. So our ischial tuberosity is actually going to be right here on our ischium. And that's also called your sit bones. Oftentimes they use that word in yoga.

But if you put your hands on your butt right now and you kind of like wiggle around, you'll be able to feel your ischial tuberosity is kind of poking through right there. Okay. So that's what these are. Ischial tuberosity.

Alrighty. So now that we have those two landmarks. What I want us to do is I want us to learn about a few ligaments that attach to those landmarks.

And they're pretty important because they can be sources of pain, but they're also sources of stability. So our first ligament that I want us to learn is our sacrospinous ligament. And it goes from our sacrum to our ischial spine.

So it's just going to come right across, just like that. Sacrospinous ligament. So remember this is like soft like connective tissue this is not bone but I want to show you two ligaments. Our second ligament is going to be our sacrotuberous ligament which is going to go from the ischial tuberosity which is why it's sacrotuberous. and it's gonna go to the sacrum so that's what's called sacrotuberous and that's gonna go like this sacrotuberous ligament now remember how we had our asis and aiis anteriorly We're going to have something comparable posteriorly.

So it's going to be these two little pointy things right here. That's going to be our PSIS or posterior superior iliac spine. Because remember, wherever we see our iliac.

crest that's where ilium is and i'm also going to do our piis our posterior superior oops i wrote that wrong It should be inferior. I got in my groove there. I-N-F. Ooh, that's a little messy, but it should be posterior inferior.

Iliac spine. Alrighty, so that kind of does it for our posterior pelvis. Make sure you're also referencing the anterior pelvis and our different muscles.

And later, what we're going to actually learn about is pelvic floor muscles that actually form a little hand. right here as well. And like what we talked about before, those muscles can actually be affected by what we call pelvic symmetry or pelvic asymmetry, which is remember, I can put my hand, my fingers on someone's PSISs or ASISs and see if one is like shifted superiorly or inferiorly. And that will help me determine if like, if these are two innominates that I'm holding in my hand. It can be rotated forward or backwards and it could be like slipped.

So anyway, that's why our pelvis is important. Now what we're going to do is we're going to continue moving inferiorly. Next we're going to move to our femur. So here is our femur. Which remember, as we learned in our first lecture, on our first day, we are going to refer to the femur as our thigh.

Oftentimes when people are talking about an entire lower extremity, they'll refer to it as their thigh. their leg, but that's actually incorrect. The upper part is our thigh and the lower part is our leg. Now, as always, let's start by drawing things out.

So I'm going to draw two different views. We're going to start with an anterior view. And this is going to be, let's see, this is going to be our right femur. I'll just write that down.

Right finger. Just so we know. In case you're looking at the models and you're kind of getting a little mixed up. Alrighty. So in our anterior view.

Bear with me again as I draw this guy out. All righty. Oops, I messed up and kind of drew him a little too skinny.

Let me make him a little wider. There we go. No one ever knew.

All right, our femur bone is pretty long, so I want to show you that. If you're ever getting confused, oftentimes people get confused between arm bones and leg bones. Your femur is the biggest, longest one, okay? Alrighty, that's our anterior view and then while we're at it, let's also draw our posterior view.

I'm gonna try to kind of make these match up, but we'll see how it goes. Alright, we got our femur nice and big and long. Sweet. Okay, there's our poster review.

Now we get to the fun. all of the labeling alrighty what do I want you to know so let's start with let's start with the head of the femur the head is this ball actually it should look like a little more like a ball type structure I didn't do too gray there there we go now that looks like more of a ball right Alright, remember we have the head of our humerus as well and the head of the radius. So a lot of bones have these same type of names.

Alright, I'm gonna write these at the bottom. Head. Then we also have a neck. Remember we have a neck of the humerus and neck of the radius as well. Thank Alright, then we have our greater and lesser trochanter.

Remember we had our greater tubercle before and lesser tubercle on the humerus? Well, here we have a trochanter. So, let's label those.

Let's see, let's do our greater trochanter right here. It's going to be this big piece. Tear, tear. Alright, and if we have a greater trochanter, what else are we going to have?

That's right, we're going to have a lesser trochanter. It's going to be right here. And it's just smaller, that's why it's called lesser trochanter. Alrighty.

Now, what else do I want you to know? I think that's pretty much it, superiorly. You're going to have something on the posterior side of the humerus, and it's just going to be this line kind of going down the center, and that's just going to be called your linea aspera, and that is a place where some muscles will attach. Actually, your hamstrings, which is on your posterior thigh. Alrighty, now we're going to jump to the inferior part of the femur.

And remember how in the humerus we talked about epicondyles and then technically... something that we call, we have different names for, but they're technically our condyle. Well, here we're actually going to have something that we do actually refer to as condyles, as opposed to the humorous where we had different names.

for them. So we're going to have a medial and lateral condyle. So let's actually, you know what, I forgot to write. This is lateral. This is medial.

The head of the femur is going to be facing medially. So we have our Medial and lateral calm down. Now, what did we have above the condyle when we're looking at the humerus? We had medial and lateral epicondyle. So let's label those here because we actually have the same thing.

Right here. right here and then anteriorly we can only see the epicondyles we can't see the condyle so it's gonna be right here and here epicondyle epi means above just as a little reminder And then something else we're going to have on the posterior side is something that we call the intercondylar fossa. That's going to be right here.

It's just going to be a fossa, so like a shallow depression. And it's going to be in between the contiles, which is why it's called the intercondylar fossa. Now, one other thing that I want to include here is you'll see like a little surface right here on the anterior femur. And that's going to be nice and smooth because that's where our patella or kneecap will sit.

Okay. So, what I'll do is I'll actually draw that out in our next drawing and we'll draw out the end of the femur with the patella or the kneecap sitting there. And then we're also going to draw the tibia and fibula, which are our leg bones. So here we're going to talk about our tibia, fibula, and patella. For these there aren't quite as many structures as there were for the femur so we're just going to draw things out anteriorly because posteriorly there's not really a whole lot of things that we need to locate so we're going to draw an anterior view.

So let's start with the distal end of the femur. We have our epicondyle coming down. Alright, so that's our femur. And then we have a little surface here for our patella. So your patella is your kneecap.

So that's actually going to be sitting over it. Kind of like that. Um, and then what I'm going to do as I've done for other joints is I'm going to draw the tibia and the fibula, but normally it'll be sitting right underneath the femur, but I'm going to draw it a little bit separated just so we can see, um, like the joint surfaces basically.

So let's start with the, this is going to be, right structure because this is going to be lateral and medial. Alrighty, so our tibia is the one that actually like articulates or forms a little joint surface with our femur so it's gonna look like that. Alright, so that's our tibia and then our fibula is actually going to be squished right next to it.

Right here. And this should actually be a little bit wider. And then we're going to have part of our femula coming down just like that.

Okay? So this is our anterior view. Now, what do I want you to know?

So let's label our patella first. Our kneecap, remember that's sitting anteriorly to our femur, but I'm just drawing our femur behind so we can kind of see, almost like we have x-ray vision, we're looking through the patella to see what the femur looks like there as well. So let's label it patella, and then I'll also label our femur posteriorly.

Let me get pink. And I messed up and I actually drew the femur a little bit small compared to the size of the tibia right here. So just keep that in mind.

That our femur, the distal end of the femur is going to be kind of like just about the same size as the superior part of the tibia. Maybe a little bit bigger. So that's our femur. And what's... interesting is a lot of times people will have knee pain and they actually go through the process of getting a joint replacement because on their x-rays um you'll see that like the the cartilage has worn down on the knees and there is a little bit bit of damage to the bone, but actually what people don't realize is what causes a lot of the pain oftentimes is the patella itself rather than the knee joint, which is the joint between the femur and the tibia right here.

So that's something that we really have to pay attention to if you enter a field like physical therapy or if you're a physician or physician assistant or nurse and you're dealing with someone with knee pain, oftentimes it's important to have them assessed by. a physical therapist and have them look at their patella to make sure that's not the source of the knee pain. Because imagine going through a huge joint replacement, which is a really big surgery, and then finding out that it was actually your patella that was causing the pain, even though you happen to have some breakdown on the surface of your actual knee joint. Alrighty, so we're going to have condyles here as well.

We have a lot of condyles in the body, so we're going to have medial and lateral condyles. condylus here on the tibia. So it's going to be right here and right here. Medial and lateral Actually, you know what? What I forgot to do before I started was label which one is the tibia and which one is the fibula.

So let's do that first. tibia fibula you know which one is first because well i remember it is the fibula has an l in it so we know that that is our fibula because there's an l and l is what lateral begins with um you can also remember it because the fibula is really skinny and off to the side and that kind of looks like an l as well um or just come up with your own way of remembering it so anyway that's our our tibia. Those are our common dials.

Let's see. Then we also have something called our tibial tuberosity. And that is going to be right here. And we're going to have some pretty important ligamentous and some would say like muscular, but basically you're just going to have attachments there that come from your quadricep and your patella. Oftentimes because of those soft tissue ligamentous attachments on that tibial tuberosity, it's pretty common for individuals to have pain there, especially as they're growing.

There's something called... Osgood slaughters, which is a condition where people have pain at that location. So, you know, all of this anatomy is clinically relevant. Now let's see.

Oh, the other thing that I missed here that I want to label is our... Our lateral malleolus and our medial malleolus. So the medial one is the one on the tibia and the lateral one is the one on the fibula.

Oftentimes people will fracture those little parts sticking down the malleoli of the tibia and the fibula and they'll say like, oh, I sprained my ankle. Oftentimes it's actually not their ankle itself. It's a fracture of their tibia or their fibula.

Alrighty. So one or actually two last things. We, just like in other strokes. we have a head and neck.

We're also going to have a head and neck of the fibula. So our head is always going to be up at the top here. That's our head of the fibula.

And then we'll also have our neck. Right there. Alrighty, so that covers our leg. So we jump back up to the femur, covered our patella, and then we covered all of these landmarks in our leg. Now what we're going to do is we're going to move to the foot.

Alrighty, let's draw a foot. That's the last part of our lower extremity. We're going to draw a superior view.

And this is going to be a right foot, just for reference, if you're looking at the models and get a little confused. Alrighty, so let's start with... We're going to start at the, so remember this is a superior view. We're looking down on the foot.

So this is as if you're like sitting in your chair right now and you look down at your foot and see the very top of your right foot. So let's start at the bottom here. We're going to draw a few bones. And the foot is another funky one because, you know, we can look at this in a superior view, but we can also look from a different view and it's going to look completely different.

So this is just the easiest way for us to identify all of these different foot bones is by starting with a superior view. Alrighty, so we got our main bones right here. These are actually called tarsal bones.

Remember how we taught called the wrist bones, carpal bones? Well, all of these are called our tarsal bones. tarsal bones and they're analogous to our wrist bones but these are really like our ankle bones right here so let's get into the other bones that we have remember we had metacarpals well we're also going to have metatarsals in the foot so that's what i'm going to start by drawing out right here so And these don't have to be perfect. We're just trying to get the gist of them.

And our fifth one kind of pokes off the side here. Sweet. Now I'm not going to make the same mistake I did in the hand by fusing my bones when I drew them so...

Our big toe is kind of like our thumb in that there are only two phalanges. And what's nice is we use the same terms in the foot that we do in the hand for these little toe bones. It's kind of cool to think about all of these little bones just like being inside of our feet and all working together. Almost done.

Alrighty, here we go. So now that we have all those out, we are going to label them. So what I'm going to do is I want to, let's see, I'm going to just write a little sign here because I want us to remember that these are our tarsal bones. Alrighty, so for our tarsal bones, we have our talus.

That's this one right here. Then right next to that and actually like below it so like more inferior on the body what we call the like the heel of our foot is our calcaneus. So we can only see the side of it but there's some of it is hidden underneath the talus.

So that's also one of our tarsal bones. These ones in our feet, you know how I said our tarsal bones are analogous to our carpal bones and our wrists? Well our tarsal bones are a lot bigger than those carpal bones. Calcaneus, which is our heel bone right there.

Now next we're going to have our navicular right here. Our navicular is really important. You can see if someone has like a low arch where their foot is a little more collapsed, it's something called the navicular drop because it's dropped closer to the ground. Then off to the side right here we have something called our cuboid. This is actually a common place where people will get injured as well or their cuboid will be like displaced a little bit and it'll be like sharp pinpoint pain on the lateral.

Oops speaking of which I didn't label lateral and medial like I want to. but there will be pinpoint pain on the plantar surface of their foot right where the cuboid bone is and oftentimes the cuboid bone can kind of be slipped out of place so just mobilizing it back into place can be really helpful to relieve that pain That's our cuboid. Alrighty, then we have a group of three different bones, and they are called the cuneiforms. We got one, two. And three.

And so whenever we label anything in the foot, it's always going to be the same thing as the hand. So your big toe is kind of like your thumb. So that's always going to be number one, two, three, four, five.

As you can see, like if we follow our big toe down, this leads to number one, this leads to number two, and this leads to number three. So for these cuneiform bones, sometimes they call it lateral or like medial, middle. and lateral but sometimes I'll call it the first second and third so I'll write that down and then I'll just say medial middle and lateral or one two and three Alrighty, so now that we have that covered, let's label.

Remember we had our metacarpals in our hand? Well, we're going to have our metatarsals in our foot. That's going to be these big long bones, which is like the bulk of like the body of your foot.

And then the phalanges are going to be your toes. So right now I'm coloring in the fourth metatarsal bone. So it's the same way that we kind of like name things in the hand. And this is our fifth metatarsal. Metaparsals.

And then same thing as with the hand. That's what's so nice about this is it doesn't really change that much. So I'm even going to use the same colors we did for our hand model.

We're gonna have our proximal phalanx, which we're gonna make this nice deep blue. And like I said before, remember that the big toe only has a proximal phalanx and a distal phalanx, but all the other ones have a proximal, middle, and distal phalanx, or those phalanges. So now I'm coloring in the third.

proximal phalanx, fourth proximal phalanx, and fifth proximal phalanx. Oops. Proximal phalanx. Remember, plural for phalanx is phalanges.

Now let's color in our middle phalanxes or phalanges. And then lastly we got our distal phalanx erythroplasia. Now, I just want to point out a little bit of nomenclature that's going to be important.

First of all, oftentimes for metatarsals, you will verbally say it as your first. metatarsal but sometimes um roman numerals will be used and it'll be like metatarsal and roman numeral one etc and then whenever we're talking about the big toe remember how when we're talking about the thumb It's called the pollux or pollicis when we're referring to muscles. For the foot, we're going to have something comparable.

And we're referring to the first digit of the foot, which is the big toe. We're going to use the term hallux. Um, so if we're using that term in terms of like muscles, there are muscles with a word halicis in it. So just to make sure that we're on the same page when we start moving forward with other things.

Now this wraps up the lower extremity portion of the skeletal system.

Transcript for:Overview of Lower Extremity Skeleton

Transcript for:
Overview of Lower Extremity Skeleton