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Hello, guys. Thank you for joining us. Um, I see that there are about 1234567 people. Um uh, as part of the audience, um, I have to say thank you very much for joining us today. And I am, um, sorry that we had to change the date last minute. Um, unfortunately, had a little bit of an issue. Um, so the presenter couldn't join us yesterday. When, what? Um, as we had planned it initially. So I really do. Um I'm thankful that, you know, free is here today with us, and you guys are able to join us. We'll give it a couple more minutes, um, to get some more viewers. Uh, just just for a few minutes, and then we can crack on. Okay. Thank you. Hello. Um, so thank you. Once again, for all of you guys joining us, um, today we'll be talking about the lower limb, Um, as part of an alchemy series. First of I'd like to introduce myself. My name is Cathy. Um, I am hosting the series along with my, um, colleague called Oscar, who may have seen before, um, in our previous sessions. So today. We're very lucky to have Doctor Freak Week who will be presenting about the lower limb. She is a core surgical trainee herself, actually. Post course surgical trainee. Now, um, and so we're very lucky to have her, um, to present this anatomy session. Who's aspiring to be an orthopedic surgeon. So, um, over to you. Free to thank you. Shruti. Um just want to make sure it's you can hear me. Yeah, I can hear you. Okay. Okay. Good evening, everyone. Today's lecture is on the lower limb. Um, and I'm through her, as Shruti has kindly introduced, so there's quite a lot to get through in one hour, so I've tried to condense it a little bit, um, so that you're still getting all of the relevant facts. Important facts. Um, but, you know, I've tried to make it doable in in an hour's time. Okay, So when we say, uh, the lower limb we're talking about the low extremity, which is all of the leg. Um, and it really extends from the gluteal region right up to the foot. Um, the muscles of the lower limb are larger and stronger than the upper limb and the function really is, uh, to provide stability, locomotion and and to help maintain posture. And that's why we find some of the biggest muscles and structures in in the lower limb. I mean, there's a lot of elements to talk about from the lower limb, and I thought it would be nice to start with the bones and the joints. Um, just puts things a bit better into perspective. So when we talk about the bones of the lower limb we're talking about right from the pelvis, um, and how it articulates with the femur, the the bone in the thigh, um, extending to the tibia fibula and then all of the bones in your foot. The hip joint is the articulation between the pelvis and the femur, which is a ball and socket joint. Um, I'm sure a lot of you're familiar with this, but it's important to start with the basics allows us to do a lot of different functions at the hip joint, um, flexion extension, abduction, abduction, and sir conduction. Whereas the knee joint were mostly able to just flex and extend. Um, this is between the joint is between the femur tibia and the patella and it's a hinge type joint, and we'll talk about these joints in detail in a minute. The ankle joint is also a hinge type joint, and it allows us to plantarflex I pointing. It holds downwards and dorsiflex upwards. Um, and it's a, uh, an articulation between the tibia fibula and the talus bone, which is one of the tassel bones of the foot. So when we talk about the femur, which is the bone of the thigh, it's one of the largest bones in the body, and it's a very strong, uh, structure. If you remember, it's a weight bearing bone, and it has to carry a lot of the of the load. Um, and therefore it's a very strong structure. It's got four main protrude Vince's, which are the head of the femur that just just here the greater Trochanter, which is here the lesser trochanter, which is here, whether these provide articulation points. Uh, excuse me. Attachment points for muscles, and then you have the lower extremity, and the shaft of the of the femur is cylindrical. But if you were to look on the posterior aspect of the femur, there's a rough, uh, portion, which is called the Linear a sparrow. And again, it's a point where the muscles attach at the distal end. You've got the condoms, which go on to articulate with the tibia, which helps us form the knee joint. And if you can see here, there's a mention of the patella surface, and this is where the patella would sit, Um, in the articulation for the knee joint in the lower leg. On the medial aspect, we have the tibia, so the typical receives the weight from the femur, and it transmits this weight down to the foot. So it's another weight bearing bone, and it's another strong structure. It articulates with the fibula, both approximately here and distally. Also excuse me. Between them there is the interosseous membrane as well. The fibula is the bone that's more lateral, and it's not a weight bearing bone. And if you see where the fibula articulates with the tibia, uh, on the posterior attachment you can see you can kind of understand that it does not form part of the knee joint because it's too inferior. However, on the distal aspect, it does articulate with the tibia, and it also helps in stabilizing the ankle joint. I'm sorry. There's not a slide in this. I thought it was on the on the next page. Uh, actually, I will talk a little bit about, um, the role of the fibula. And it's, um, and how it helps in stabilizing the ankle. Um, once we go on to the ankle joint, I think that's further down the presentation. Uh, so the foot helps in supporting all of the body's weight, and it acts as a lever and helps to propel the body forward with its arches. Excuse me? The bones. Um, uh, the calcaneus bone, which is a large bone here that forms the heel. Um, it also carries the tales on top of it, which is involved in, um uh, forming the ankle joint. And also, it's where the attachment point for the Calcaneal tendon. There are six tassel bones which are here, and they include the tailors, the navicular, the cuboid, and also the uniforms, which are the medial, intermediate and natural kuna forms. Um, these bonds would then articulate with the metatarsals which are here, uh, five of them, and they go on to articulate with the phalanges three in each toe except for the greater, which there's only two in there. So there's 14 phalanges, so that brings us nicely onto the ankle joint. Um, this is a hinge type joint, which I mentioned, and it allows us to do the Dorset flexion and plantar flexion motions in the foot. Um, and it's formed by the articulation of both of the lower limb, both of the lower leg bones, the tibia and fibula and also the tailors. And you can see in this X ray here how it's it's, um it's sort of like a socket where the tibia extends around, Uh, the tailors and the fibula, uh, lies laterally. Um, here we have a joint between the fibula and the tibia, and we call it a joint because there are tendons that lie across this, um uh, and keep them attached. And we call this the uncle the Uncle Cyn. Osmosis. Um and that's important because I will talk about what happens when you get an uncle fracture in a minute. So here we can see again how the tibia fibula and Taylor's articulate to form the the ankle joint. Uh, and then this is the subtalar joint where it's the tailors and the calcaneus come together, and there's ligaments here as well. Um, the shape of the Taylors is thus that it. It's wider anteriorly, and it's more narrow. Postural e. Therefore, when, uh when when your foot is in a dorsiflexion position, it's most. It's the most stable position for the uncle. So this is a classification system for ankle fractures. And it shows, um, the three types of ankle fractures as per the Weber classification. And the difference is where the fibula is fractured. If it's, um, more of a distal fracture. And as it becomes more and more proximal, we say that the likelihood, um, there's an increased risk of a rupture of the Sindh. A small cyst. So an syndesmotic disruption equals an uncle. Instability. Increased chance, uh, increased amount of ankle instability. Um, and if it's more of a distal fracture here, there's less likely that they'll be rupture at the Sindh osmosis. So talking about ligaments, there are other Liga ligaments we need to think about as well. On the medial aspect of the ankle, we have the medial or deltoid ligament, and it is made up of it's just here, and it's made up of four separate ligaments that come together to make the the Delta Ligament. It's quite a strong ligament. Um, attaches the tibia to the navicular calcaneus and the Taylors. And on the, um, lateral side of the foot, we have what we call the lateral ligament. And it's made up of these, um, structures here, which is the calcaneofibular, uh, ligament, the anterior Taylor fibula ligament, which we call the ATFL. You must have heard of it in, uh, with the with the abbreviations. And then we have the posterior talofibular ligaments as well. And those three come together to make the lateral ligament. So there are a lot of ligaments that form the ankle that that are involved in the ankle joint. And we can think of them as there's a concept of of the ankle ring, Um, and the upper part of the ring of, uh, Ligament. The upper part of this ring is formed by the articulation of the tibia and fibula. So these two here, these two bones distally where they articulate this is the upper part of the ring, if you imagine. And the lower part of the ring is formed by the subtalar joint, which I said was between the tailors and the calcaneus. Um, and you can just see here this is labeled here the subtalar joint. That is the if you imagine, that is the lower part. And then the two ligaments we've just talked about now, which are the medial and lateral ligament's. They're formed the sides of the ring so you can have this ring in the ankle. And when an ankle fracture does occur, we usually, um, kind of assume that there will be a break in two parts of this ring. So you may have a fracture, and you may have rupture of the ligament, most likely as well moving on to the knee joint. The knee joint is a hinge type joint, and the main actions are flexion extension at this point. And there's two articulations that we need to think about the tibia where it articulates with the femur, where the medial and lateral condyles, um of the femur will, um, articulate with the condyles of the tibia. And this is really the This is the main part where the weight bearing occurs. The load is passed from the femur to the tibia. Remember the fibula is not a weight bearing bomb. We also have the patella which attaches to the femur. Here, on the on the distal and anterior aspect of the, uh of the femur is where the patella will attach. And if I just show you on this slide, you can see the green, uh marked portions show where the tibia and fibula articulate with each other on either bone. And you can see on the red portion is where the patella would articulate with the femur, the tendon of the quadriceps, which are the muscles of the anterior thigh that come together. Um, they insert directly onto the patella and you can see that in the red, uh, marking here. So we have four anterior thigh muscles that come together and make the quadriceps. And that tendon inserts on to the patella here. And then the patella goes on to attach to the tibia by the patella ligament. And this one is called the Quadricep. Sorry, the quadricep tendon and the patella tendon or the patella ligament. Because the patella resides within the quadriceps tendon, it provides a fulcrum on it. It gives an increased power to help the extensive mechanism of the need and and it also helps to reduce the frictional forces on the femoral condyles where they articulate with each other other than the articulation of the bones. We also need to think about the mini sky, and there are other ligaments in the knee. Um, which I'm not going to talk about today. But they're they're further ligaments that we could think about the cruciate ligaments, the anterior and posterior, um, which are tested with the anterior and posterior drawer tests. But we also have the meniscus I and the meniscus I i r c shaped structures which would sit here and here and a C shaped position. And they're fiber cartilage structures that help deepen um, the articular surface of the tibia, where the former, uh, femoral condyles will sit So it really allows more stability of the knee joint. So it just makes it a little bit deeper for those condos sitting there. And the other function of these fiber cartilage structures is to act as shock absorbers, uh, and and sort of just dissipate the forces from from when they're jumping, skiing and things like that. If we go on to, uh I just wanted to mention Also the test for the mini sky is the McMurray test that we would use. Um, so it's when you would apply. Apply, um internal external rotation and apply valgus and various stresses in different patterns to check for, for for for the rupture of the of the mini sky, both medial or lateral. Whereas the draw tests of other cruciate ligaments. The hip joint is a ball and socket synovial joint, and it's where there's articulation between the acetabulum of the pelvis and the head of the femur. Um, very important joint. It's where it's the main varying portion, and it's where it provides stability to the skeleton. If somebody has a hip fracture, um, they will become immobile because of the pain, and they would struggle to wait there. The acetabulum, which is where the head of the femur sits. Um, it's a bit deep. It's like a cup, um, and again has a fibro cartilaginous collar. A bit like when we mentioned the meniscus, I on the knee help to deepen um, the surface for the funeral condoms again, this helps the acetabular labrum is what we call it, and it helps deepen the cavity where the head of the femur will sit and the head of the femur is hemispherical. And it's, um we'll go and nicely sit in there. Um, and both services have a cartilage, um, where they articulate if we think about the neurovascular supply of the hip, it's very important. Um, it's provided by the medial and lateral circumflex femoral arteries, which are branches of the profunda femoral, um, artery. So we'll talk a little bit more about arteries further in the presentation. But just to make it a little bit clear, the femoral artery gives off a branch, which is the profunda femoral artery, which you can see here, which is a deeper brunch. And this gives off the lateral and the medial circumflex arteries. Um, and it's mainly the medial, um, formal circumflex artery that that provides most of the arterial blood supply to the, um, femoral head. So if you were to get, uh, mostly an intracapsular fracture of the neck of the femur, um, so a fracture through this portion, um, you're likely to disrupt the blood supply to the head of the femur, And that's why it's very important for the patient to undergo surgery because you will. It will lead to avascular necrosis because they've lost the supply of the blood to the head of the femur. The hip joint is primarily innovated by the sciatic femoral and obturator nerves because these are the same nerves that will supply the knee. And it explains why you can have pain that is referred from when you have a hip injury have referred pain to the knee and vice versa. This slide, um, is mainly to show you all of the all of the movements that we can do at the hip, which include flexion extension, abduction, which is outwards abduction, internal and external rotation. So there are a lot of movements that can occur at the the hip joint, um, which is not the same for other other joints in the lower lower limb. It's the most, um, most rotation that you can get. Um, and there's a lot of muscles that are involved in this. I'm not going to read them all out, but you can see that there's a lot of muscles that involved in every movement, and therefore, if you do, um, have injury to one muscle, there are usually others that can compensate. I thought I'd talk about the arterial supply before we go on to talk about the muscles because it would make it a little bit easier. Um, as we go on. So the main arterial supply to the, um, lower limb comes from the external, uh, from the femoral artery, which is a branch of the external I lack. So the external iliac, a major branch of a branch off the aorta, which goes on to give you the femoral artery. It's a continuation of the external and yet, um, and it becomes the femoral artery once, um, the external area crosses under the inguinal ligament and enters into the femoral triangle. And that's where you then get the femoral artery. And it's within the femoral triangle that the profunda branch, the profunda femoral artery, will come off. Um, and it passes that the posterolateral aspect. Um, and we'll will travel distally giving off three main branches. So here it gives off the lateral and medial circumflex arteries, which I already mentioned earlier. Um, and we know that the medial circumflex artery here will excuse me. The medial circumflex artery will sort of wrap around the neck of the of the femur and and provides the main blood supply there. And and the lateral femoral circumflex artery, um, supplies some of the muscles and the lateral aspect of the thigh as well. It also gives off perforating branches. Um, which, um, will perforate the one of the muscles in the thigh the adductor magnus and then goes on to supply muscles in the medial and posterior thigh. Um, once the is exited, the once once the femoral artery has exited through the femoral triangle, um, it will continue down the leg in the anterior aspect of the thigh. So remember, it's on the anterior aspect, and therefore it's going to supply the muscles on the anterior portion of the thigh and they'll go through a tunnel, which is called the Adductor Canal, and it will come out here, which is the adductor hiatus. And as the federal artery moved through this opening and it will enter the posterior compartment of the thigh, Um, and that's when it becomes the popliteal artery. So you have the external area continuing as the femoral artery, giving off its branches to, um, um, supply the femoral head, supply the lateral thigh give up. It's perfect. Branches, um, passes through the adductor canal. And then as it passes through the adopter hiatus, it will pass posterior to the leg now and you. As you can see, it's starting to go behind the femur. And that's where it's passing into the, um uh, popliteal fossa and becoming the popliteal artery. And this is the Popliteal fossa. Um, you can see the borders are highlighted here on the slide. Um, so it's the medial and natural heads of the gastrocnemius, which provide the medial and lateral borders in few early because it's remember, that's here and here. Remember, this is the popliteal fossa is sort of a diamond ship. And then Superior Lee, you've got naturally immediately. December remember semimembranosus and the biceps femoris. And so these four structures form the property of fossil, which is a diamond ship, and through these, once the femoral artery passes through, it becomes the popliteal artery. I just wanted to mention also, um, there are other arteries in the thigh as well, other than the femoral artery that we should probably talk about. And that's the the obturator artery. Um, the femoral artery arises from the external iliac artery. But the obturator arises from the internal iliac artery, um, in the pelvic region, and it descends in the Obturator Canal and to enter the medial thigh. Whereas the femoral artery is on the anterior thigh and it gives off two branches, the anterior and posterior branches. Um, and it goes on to supply muscles in the in the thigh. Um, so the main thigh muscle, uh, the main, uh, arterial supply in the thigh is from both obturator and femoral. So we mentioned how the femoral artery becomes a popliteal artery. Uh, once it's gone through the foster here, it will become It will spit into the anterior tibial and the, uh, tibial perennial trunks. And you can see that here where the popliteal artery continues to give off the anterior tibial artery and the tibia perennial and the tibia perennial further divides into the posterior tibial artery and the fibula or the perennial artery, the anterior tibial artery. It passes, um, anteriorly, and it'll pass between the tibia and fibula. Um, and it will go on and continue to give you the dorsal pedis artery watch, which we often pulpit in vascular patient's in the or in any patient. Um, but it is the anterior tibial artery that continues, um, um, down the length of the of the of of the leg and continues to become the dorsal pierce. But it passes. Anteriorly was here. We can in this picture, we can see the posterior portion of the leg. Um, and there's the anterior tib latter coming off, and then this picture, you can see this is where it's gone, and it's continued to give you the docile is Peter's. Uh um, So that's the the arteries. But also I thought it would be important to talk about the nerves. And so we have the femoral nerve. This is one of the major peripheral nerves of the lower limb. Um, it's nerve roots R L2 and L4, as you can see in this picture above. And the motor functions are to innovate the anterior thigh muscles, which flex the hip joint, Um, and it helps to extend the knee with the quadriceps. For Marist, Muscles also provides some sensory functions. Supplies contain cutaneous branches to the um anteromedial thigh and the medial side of the leg and foot as well by way of the stiffness nerve. It's one of the largest branches of the lumbar plexus. Um, and as I said, it will provide the down supply to the anterior thigh supplies, the hip flexes and the knee expenses, and we'll go on to see more of its function later on. Once we talk about the muscles individually, we also have the sciatic nerve, which has nerve roots L4 and S three and its main motor functions. Uh, innovates the muscles of the posterior thigh, which include the biceps, famous semimembranosus and semi tendinosis. And these are the hamstrings. Um, and it also, um, provides branches to muscles of the leg and the foot. There's no direct sensory function from the sciatic nerve. Okay, so the muscles in the thigh so the upper part of the leg can be divided into three compartments the interior medial and posterior compartment, Um, the muscles in the anterior compartment of the thigh. They're all innovated by the femoral nerve, which we've just seen. And, um, as a general rule, they all, uh, come together to extend the leg at the knee joint. Um, the major muscles are the pectineus, the sartorius and the quadriceps, which is made up of four muscles, but also the iliopsoas muscle. Um, which passes into the, uh into It's just that the end of it, which passes into the anterior compartment. And you can see them all here. Um, and the quadriceps are made up of the rectus femoris, and you've got the fastest medialis and the medial aspect of the thigh, and you've got the vastus lateralis. You also have the vast ist uh, intermedius, which is below the rectus femoris. So you can't see it in this picture. But the four of those muscles would come together to make the quadriceps. And they are the ones that give the quadriceps tendon that attaches at the superior pole of the patella, which we saw earlier when we were talking about the knee, Um, and then the on the inferior aspect of the patella, you'd have the patella tendon which attaches to the tibia. So together, these are the quadriceps and they are the one of the major muscles of the anterior thigh. Um, then you also have the sartorius and pick tennis and Elia Sauce. So I've put this table in here, which will be available to you so you can sort of go through the sites of attachment and origin and talk about and look back again at the function again. Um, so the list So it's really is to separate muscles, um, the service measure and the Yakis. They both originate in different areas areas, but they'll come together and they give one common tendon. Um, and therefore they treated like one muscle. Um, unlike other anterior thigh muscles, the iliopsoas doesn't extend, um, the leg at the knee joint. Um, the source major originates from the lumbar vertebra and the Eliquis. It comes from the iliac fossa of the pelvis. So they come from the pelvis, and together they will both insert onto the lesser trochanter of the femur, one of the protrude Ince's of the femur we saw earlier. So together, the main goal of this is to flex the thigh at the hip, and they innovated, um, by either the anterior remai of the L1 to L3, which is the source, major. Or the Eliquis, which is, uh, provide provided with nerve supply from the femoral nerve. The quadriceps. Um, like I said, our for individual muscles. And if you see, we know that they're common. Site of attachment is the onto the quadricep tendon. They all come together to be the quadriceps tendon, but the fastest lateralis originates from the greater trochanter. Um, whereas the, um whereas where if you look at the fastest intermedius, it comes from the anterior lateral services of the femoral shaft. And the media list comes from the intertrochanteric trochanteric line of the middle lip at the linear aspira, which is on the on the posterior surface of the femur. I'm sorry at this point, Um, we're just going to take a two minute break. I think I just need to put a charger in. Thank you. Um, uh, I just want to let the audience know if you have any questions. Please do use the chat function to type them. You know, you can read them out towards the end. Thank you. I'm sorry about that. We can continue with this now, so all of the quadriceps muscles are all innovated by the femoral nerve, and you will notice that the rest of the muscles in the anterior thought thigh all innovated by the femoral nerve as well. Um, the quadriceps is the main expenses of the knee. Um, and and like I mentioned before, the patella helps in providing, um, extra strength to the extension of the knee. Um, the big the pectineus muscle is a sort sort of, a small, flat muscle. Um uh forms the base of the femoral triangle. And and it's it has a dual innovation innovation, both from the femoral nerve and from the opportunity to nerve. So that's the only one that has a bit of both. Um, so they are the ones that we really need to talk about, and the rest is really just coming across, um, learning the insertion or urgent points. I just want to mention about sartorius, which is the longest muscle in the body. It's a very long and thin muscle, and you can see that in this image if I can go back to him. Yeah, is the purple muscle here? And it's one of the longest muscles. Um, and originates are the basis the anterior superior next time and it attaches onto the interview. Um, but it also at the hip joint is the flexor. Um, but as the knee knee joint as well, it functions as well. So it goes across two separate joints, and it seems to be the only one that does that. So because of its attachment points starting at the anterior superior Alex Pine and then ending on the surface of the tibia, you can imagine that it would help in both flexion of the hip and flexion of the knee that takes us on to another compartment of the of the thigh, which is the muscles of the medial thigh. Um, the the adductors. Um so you have the adductor brevis longest, and Magnus, you have the operator externals, and you have the gracilis. Um, and the muscles in the middle compartment collectively just returned the hip abductor hip abductors together they are. They are all innovated by the obturator nerve. Um, which again, uh, arise from the lumbar plexus. And the arterial supply is the obturator artery. The obturator externals also helps to externally rotate the hip by the others. Adducts at the hip. And it's the adductor magnus, which you can see here in few early in this of reddish tone, which is the largest muscle in the media in the medial compartment. And it's the most posterior to the other muscles as well. May can be divided into two parts. It's got both an adductor part and a hamstring part, and it's the adductor part that comes from the inferior my of the pubis and the ratio of the issue. But then attaches onto the linear sparrow. The rough surface on the on the posterior aspect of the femur and the hamstring part originates at the issue of Tuberosity and attaches onto the adductor tubercle of the superconductor line of the female. Um, both of them act together to abduct the thigh. So these are the adductors. Um, but the adductor component also flexes the thigh, and the hamstring portion will extend the thigh, and that is the difference. So the two portions of the adductor Magnus, the the the the function, the difference in the function is that, um, the doctor component will flex the thigh, and the hamstring portion will extend the thigh even though they're both addict, too. The doctor brevis. Um it's just a short muscle, and it lies underneath the adductor longest, and you can see it quite clearly here, but normally it would lie underneath. Um, and it it lies between the anterior and posterior divisions of the obturator nerve so it can be used as a landmark to identify. Um, some of the branches? No, the grocery list, which originates in the pubic bone. Um, it goes on to insert onto the medial aspect of the shaft of the tibia. Um, and the gracilis, um, sartorius and semi tenderness come together to form something that's called the pet anserinus. And sometimes this can become inflamed. Um, and it's the attachment point for the three of these muscles together, um, on the medial side of the tibia, um, where you will have pain there. And it could be any one any one of these three muscles that will be, um, inflamed at its distal attachment site. So it's the chrysalis, sartorius and simultaneous. And it's the pest, uh, answering us. Which is it's it's name. Um, it's the Brazil is is the most superficial, um, and medial of the muscles in this compartment. And again, it crosses both the hip and the knee joints. Um, and sometimes it could be transplanted into, um, the upper limb to replace damaged muscles. There, the muscles in the posterior compartment of the thigh. Uh, the hamstrings, um, and There's three muscles um, to talk about is the biceps femoris? And it's because it's called the biceps. You can assume it has two heads, um, the semi tendinosis and the semimembranosus. Um so, like I said, like the biceps break I in the arm. It has, uh, the biceps memories has two heads, a long head and a short head, Um, and it's the most lateral of the muscles in the posterior thigh. Um, the common tendon of the two heads can be felt most laterally in the in the posterior thigh. So if you were to palpate the tendon that you can feel on the most lateral aspect is the tendon of the biceps farmers. So it's a long hair comes from the issue of curiosity of the pelvis, and the shower head comes again from the linear sparrow, which is the rough surface in the back of the femur. Um, and they come together to form one common tendon, which attaches onto the head of the fibula. Um, so the fibula forms an attachment site for many muscles, but approximately, um, but approximately does not come to to join the other bones do have any varying function and the muscles in the posterior thigh are innovated by the tibial nerve, which is one of the main branches of the sciatic nerve. Um, so we said that the thigh is divided into an interior medial and posterior compartment, but in the lower leg we divide the leg into four compartments, which is the anterior lateral, superficial posterior and deep posterior. So here we can see the anterior compartment of the lower leg. So we're now talking about the lower leg. Um, and there's four muscles in the anterior compartment. There's a tibial is Ontario extensor digitorum longus, and when we talk about digitorum, we know that they would be going to the digits extends the halitosis. Longest analysis always means toe the greater and February's or peroneus tertius. So all of the, uh, vessels or muscles or, uh, that, uh, in the lower leg and laterally can either be called February's or peroneus. Um, and they're the same thing. So collectively, these muscles the dorsiflex the foot, which is sort of your toes pointing upwards, and they also help to invert the foot at the ankle joint and the Extensor Digitorum longest and the Extensor House. As long as they both also help to extend the toes. And and these muscles in this compartment are supplied by the deep perennial or fibula nerve, which has a nerve root of L4 s one. And the blood supply in this region is the anterior tibial artery. So as we can see the extensor digitorum, uh, longest, um goes on to insert on to the distal finance of the second to fifth digits. So it'll help with extension there, and this is on to the first digit, the big toe. So we'll help with extension of the first toe. And as the TB Ellis anterior inserts into the medial side of the foot, um, you can expect that it would help an inversion of the foot. The lateral compartment is made of two muscles alone, the peroneus or February's longest and brevis. Um, and the common function of these muscles is e version, um, turning the soil of foot outwards. And and they're both innovated by the superficial perennial nerve. So, um, realistically, only, uh, you only really get a few degrees of version. Um, because you can't really there's not really that much movement in that direction, whereas you can get a greater deal of inversion, and you only really are able to avert a little bit. And the February's or Pyrenees longest is the larger or longer ones of the of these two muscles. Um, and you can see that here because the hilarious longest is the blue one, and it continues under the foot to go further than the hilarious brevis, which ends here. So the fibula is brevis will go on to attach onto the styloid process of the fifth metatarsal, whereas the fibula is longest continues on to the medial cuneiform, which is one of the bones we talked about earlier, which is further away. So you can imagine it has a longer route, and together they will avert the foot. We also then have the posterior compartment of the lower leg, which is divided into a superior, uh, sorry. A superficial and a deep portion. And the superficial muscles, um, of the posterior compartment. I have three main muscles and they these are the muscles that help to give the the shape of the cough, the shape that we see. Um, the sort of rounded, characteristic ship, Um, and they all continue on to insert onto the calcaneus or the foot and you don't remember earlier when we were talking about the calcaneal bone and I said, This is the site by the Calcaneal tendon would attach, but that is where the common attachment site is, and you can see that here in this picture. So we have the gastrocnemius plantaris and the seller as well as and altogether these muscles. We're going to help to plantarflex, which is of your tours pointing downwards and help to invert the foot as well. And these are all innovated by the two billion of one of the terminal Bunches of the sciatic nerve. The gastrocnemius. Um so you can see that superficial muscles here are the ones in green, and they all come together at the Tendo calcaneus um, the gastrocnemius, which is the most superficial, which is what you would put your if you were to touch a cough. That's what you would be touching. Um, as it's the most superficial muscle. It has two heads, both the medial and natural. And remember, these are the two muscles that come together to form the inferior borders of the Popliteal fossa. So you can hear, see the two heads of the gas truck. They've just been cut away. So Gastrocnemius would be lying above here. And here is the property of Fossa and the inferior to borders are the two heads of the gastric. Here and above you have both the semitendinosus and semimembranosus of the posterior thigh, which are forming the superior bodies of the Popliteal fossa. Um, then we have the deep compartment, and there's four muscles in the deep compartment. Um, the Popliteus, um is the only one that acts on the knee and the three remaining muscles, which is the tibialis posterior flex analysis longest and flexor digitorum longest. They act on the ankle and the foot. Um, so remember, we've got an extensive analysis, and we've got an extensor digitorum. So this is just the the same version. But on the posterior aspect and therefore the other flexes, um, we also have a tibialis anterior. So now we have a tibial list posterior on the posterior in the posterior compartment. So the kind of mirror the anterior and posterior compartments kind of mirror each other in that way. Um And so, as I said, the the um popliteus is the only muscle of these that acts on the knee joint. Where's the rest? Act on the ankle and the foot, and you can see that these are also innovated by the tibial nerve. Um, and the common function is to help with plantar flexion of the foot, which is your toes pointing downwards. And you can see that the deep compartment are the ones that are in blue and just like the expenses. Um, you can see that the digitorum gone to touch to the second to fifth digits, whereas the hallucis long affects the Harris as long as a touch Excuse me, attach onto the first digit. And so these are the ones that we will, uh, move. Um, and the f d l the flexor digitorum longest is, um, surprisingly, a smaller muscle than the flex analysis longest. Um, is that picture here? So I'm not sure you can make out quite well in this picture here, but it's the digitorum longest is looking it immediately, but also ultimately is quite a smaller muscle in comparison to the flex analysis, which is only actually working on one digit. But proportionately you would see it's a lot smaller. So, um as I said, the superior muscles, um, of the posterior compartment. They come together to form the, um, calcaneal tendon. Um, and so rupture of the Calcaneal tendon would be either partial or complete tear of this tendon. Um, and it's It's most likely to happen in patient's who have, um, calcaneal tendonitis because of the repeated inflammation. Um, of that tending, Um, And you usually get that injury. Um, when you've got when you've been in a position where you sustained a forceful plantar flexion when you've, um, you've been in a position where you've forcefully happened. So I've been in that in that, um uh done that, Axion with your foot. So you've before it's gone down with, um and then the patient after this will be unable to plant reflects the foot against any resistance. It'll be too painful. Um, and and it just remains permanently dorsiflexed. Um, But the PSA less and the gastric name is can contract. Um, and then they will become sort of a little lump that you can feel at the back of the of the posterior thigh of the posterior leg in this situation, and that's when you have a ruptured calcaneal tendon and treatment is usually, um, most cases, uh, nonsurgical. And you put the patient in a cost to wait for repair. Okay, so I think that's covered everything from in terms of the musculature, the bones, the nerve supply and arterial supply to the lower limb. Um, it was a quick trip through everything. Um, is quite a large topic, like I said it to begin with. Um, but I hope you recognize that in the thigh, we have three compartments to think about individually. The anterior compartment, Um, the medial compartment, the anterior compartment, which includes the, uh, quadriceps. These are the extensive at the, um, knee. You've got the medial compartment, which is the adopters of the hip. You've got the posterior compartment, um, which, uh, the reflexes of the knee. You've got the in the lower limb, you have four compartments. Um, So when we think about compartment syndrome, patient's, um uh um uh, coming in. Uh, we we should know that there are four compartments to think about. We have the anterior lateral and posterior superficial and deep compartments. Um, the anterior compartment have the expenses at the uncle, um, and the lateral compartment. has the peroneus longest and brevis muscles, which help with the version of the foot. And then you have the posterior compartment, which are the flex is, um, And the blood supply at the, uh, nerve supply to the, uh, lower limb is all from the sciatic nerve, which, um, if you go back mhm. Yeah, um, the sciatic nerve, which emerges from underneath the reformers, um, and then goes on to divide into both the table nerve and the common peroneal nerve. Um, it is in the upper, uh, in the in the thigh. It is a sad enough, um, which is passing through, um, And then once it gets to the popular till, uh, fossa it divides into its two branches, Goes on to provide both to Tania's, um and, um uh, sorry. Both provide both sensory and motor function. Um, but is the, um, two separate branches, which then go on to divide the different, um, compartments? I hope that was very clear. Um, uh, there's quite a lot of things to talk about, Um, when it comes to the lower limb. So I try to give you a sort of an overview of the joints. Um and the ligaments. Um, and and so the main function of the lower limb. If there's any questions, I'll be happy to take them. Thank you. Thank you very much for your I know it's a very large topic to cover in an hour. Thank you very much for, um, for this presentation. Um, yeah. So any questions, please? Um, Pop on the tap. I just want to ask a quick one in terms of, uh, provision. Um, you know, for M S. E s. So I know there's so many anatomy books, But then, of course, a national books will go into so much debt. What sort of resources would you recommend? Um, for learning this, I have to say one of the best resources for anatomy. Um, I have to say one of the ones that stands out, and I think a lot of people who have studied specifically for the MRCS would say is teach me anatomy. Um, it's a really wonderful resource. It's very clear, gives you the right amount of information without going on endlessly. Um, there are some very good images, and it breaks down each compartment each region and gives you the sort of relevant amount of information. Teach me and ask me. I would definitely say is one of the rest. Um, I think I have a look at that. I think it will. It speaks for itself. And it also does a nice thing where it will talk about specific nerves that are important. For example, the sciatic nerve, which goes on to supply all of the lower limb. It will talk about the cost of the nerve, um, in detail and again for the upper limb. It would talk about the course of the the median nerve or the older nerve and exactly where it passes. So if you have a look at that, I think that's a nice way to revise anatomy. Um, it's got the right amount of clinical notes to go with it as well. It mentions any, um, any any relevance to any specific injuries that you can sustain and how they would relate. Um, so have a look at that. Thank you. Um, can you also please complete the feedback forms as well? Um, so that you can get a certificate towards the end. Um, we haven't actually had much questions. It's just lots of appreciation for your presentation. So thank you. Um, And in terms of the next sessions, uh, we the next session will be on E N t. And after me, Um, on the 11th of October, so keep an eye out for it. We will create a link and stuff. We get to do that. So keep an eye out for that. And, um, if you'd like more anatomy sessions, especially when it comes to orthopedic related stuff, so one session are looking and looking at the nerves, Um, and the blood vessels in detail. Then please let us know we're happy to accommodate. Um, but besides that, I think there's nothing else much happening in the chat. Um, so we can call it a day. Wonderful. Thank you. Yeah. Thank you. Bye bye.