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This on-demand teaching session delves deep into the anatomy and function of various muscles located in the anterior and medial compartments of the thigh. Medical professionals attending this session will participate in an interactive study of muscles such as the SOAS major, the iliacus, the Sartorius, and the Pectineus, among others. The session explains the origin points, insertions, and functional relevance of these muscles, supplemented with helpful visual aids for easier understanding. But it doesn't stop with just recognition; the program also challenges its attendees with questions to ensure active learning and retention. Whether they are new medical students or seasoned practitioners looking to brush up their knowledge, they will value this detailed yet accessible deep dive into muscular anatomy.
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hip and knee

Learning objectives

1. Understand the origin, insertion, and function of the SOAS major and iliacus muscles in the context of the muscular system. 2. Recognize the role of the SOAS major and iliacus muscles in hip flexion and their effect on the movement of the femur. 3. Identify the Sartorius muscle, its origin from the anterior iliac spine, and its role in hip and knee flexion. 4. Establish the characteristics of the quadriceps femoris group of muscles, including their origin points, their insertion into the quadriceps tendon and their role in knee extension and hip flexion. 5. Comprehend the features of the muscles in the medial compartment of the thigh, specifically the gracilis and obturator externus muscles, and their role in adduction of the hip and, in the case of the gracilis, flexion of the knee.
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Computer generated transcript

The following transcript was generated automatically from the content and has not been checked or corrected manually.

Two muscles. You've got the SOAS major muscle and you've got the iliacus muscle. Now, with the SOAS major that's originating from the lumbar vertebra. Um The iliac is, if you remember a bit early on, we talked about that, that um iliac fossa, that's where that muscle originates from. And they both kind of come together and they insert into the lesser trochanter of the femur. Um Now with the anterior compartment as a general of the thigh, most of the function um is to extend at the knee joint. There's gonna be, there's quite a number of exceptions to that. But when you're thinking anterior compartment, think extension of the knee. Um So, yeah, but with this muscle, we're talking about the iliac soas muscle is more responsible for flex flexion of the thigh at the hip joint. So we have some pictures here. So you can see. So iliac fossa, remember that's the, the iliac fossa right here, the ilium here, that muscles originating from here. And it's kind of, it's, it's uh moving downwards here into the lesser tranter. You've got the PSAs major. So remember we said it originates from the lumbar vertebra and here attaching into the lesser trachaner and you've got these kind of ignore these muscles, but just to show you how it would look like. So you've got their soas major Iliacus inserting into the lesser tranter. I just, I guess, um, think about the muscle itself when it's contracting, think of what's gonna happen to the femur. Um, you know, if you, if that muscle is contracting the, the femur is gonna come closer to your chest. So therefore, it's, it's hip flexion. Um So yeah, if you think about it in that, in that um regard, it can make it a bit easier to remember, but obviously, it's nowhere near the knee. Um So it's not gonna do, it's not gonna be responsible for any movements of the knee. So this muscle flexion of the hip. So the as we move down the Pneumonic um so spot for Sartorius uh and pretty for Pectineus. So, Seror uh the Sartorius muscle, um it's uh I think it's the longest muscle um in the body. Um I think so. Um So that will originate from the anterior iliac spine. So we're still at the ilium, remember. So I ilium, um we're thinking anterior compartment um and that will insert into the tibia, the main function of this because if you're thinking about it, it's inserting um above the hip joint and then almost below the knee joint. So we're having both, we're having movements of the hip joint and the knee joint, we have hip flexion again. Um That hip, that hip being clo brought closer to the chest and you've also got knee flexion now, right? Um I think we have, yeah, we have a little picture here. So, anterior iliac ris, that's where it's originating from and it's going down all the way down here and it's inserting into almost the medial aspect of the tibia. And if, when it's contracting, think about it, it's not gonna, it's most, when it contracts, it's not gonna, it's not gonna extend the knee. It's more because it's kind of at the medial posterior aspect of the knee, it's gonna bring that knee backwards, right? It's gonna, it's gonna bring that knee backwards and therefore, um knee uh flexion. So next muscle pectineus muscle. Now this one originates from the pubis bone. And if you remember from the start, when we talked about that Pectineal line at the back of the femur, um that's where it's gonna insert into. Uh and the function of this muscle is ad duction. And you'll see from the orientation of the fiber and again, flexion of the hip joint, not the knee joint because it's nowhere near the knee. So here, if you see the Pectineus, the pubis spoon here and it's inserting into the back that pectineal kidney. Yeah. So here you can see, remember. So this would be the linear aspera, right, that rough line and moving up here as it moves proximately. It would be the um the pectineal line and that's where it's inserting. And again, if you think about it moving wise, if this is gonna contract, it's gonna bring that femur towards the midline, isn't it? So that's a duction. Um And it's also gonna bring that hip backwards, isn't it? Uh Sorry. Uh that gonna bring that hips towards the chest. So it's hip flexion and here you can kind of see. So that's the uh pectinous muscle there. And you've got the sartorius muscle here. All right. So, next, in the anterior compartment, you've got the quadriceps, femoris. So this um consists of four muscles, really, you've got the three vastus muscles and you've got the one rectus femoris muscle. Now, the rectus femoris originates from the anterior iliac spine. So, still at the ilium. Now, um the, the, the, the media the vastus is divided into really the medial aspect, the intermediate and the lateral. But when I show you the, I mean, it's quite a lot to learn here, you know, from if you, if you think about the origin point, but when I show you kind of pictures, you'll be able to really just, just um remember really, it's quite, it's quite easy. So what you want to remember for the quadriceps, femoris essentially inserts into the patella via the quadriceps tendon. So it's quite easy insertion point. Um And that's the high yield information. Remember that and uh origin and the origin point, you don't really have to remember. But if it makes you, if it makes it um easier to remember, um you can. So you've got the Vastus medialis. If you look at the vastus medialis, remember we've got the greater tranter here, lesser tranter. And remember that line I was talking about it was the intertrochanteric line. So the vastus medial being the most medial aspect of that and uh originates from the inter L I mean, uh so that, that makes quite, it makes quite a lot of sense. So moving on, then you've got the intermediate now. So the intermediate is gonna be right beside the media, isn't it? Um And it's in between, sorry. So it's uh it's in between. So it's originating from the anti the anterior aspect of the femur. OK. And that's the intermediate muscle. And again, they're both inserting into it would be here, it would be the quadriceps tendon and now you've got the lateral muscle and again, it's, it's gonna insert further on, isn't it? And here at the lateral point, what do you have? You, you have the greater to counter. So, yeah, so quite easy to remember where they all insert. It's kind of in a, it's moving medial to lateral. Um Yeah. And they both all insert into the quadriceps, quadriceps tendon, which will insert into the patella and that patella then will insert um there'll be a ligament there that will insert into the tibial tuberosity. And here So that's the, uh that's the uh vastus muscle. And then you've got the rectus femoris muscle and the rectus femoris muscle is that anterior iliac crest? And again, inserts into the same point. Now, with movement wise with these muscles, what I want you to remember is just again, look at the origin point, look at the insertion point. So with the, with the vastus muscles, they're not crossing the hip joint. Ok. It's all crossing the knee joint. So vastus muscle um movement is knee extension. And that makes sense because it's connecting to the patella, connecting to the tibial tibial tuberosity. It's extending that knee rectus femoris, however, is also uh you know, uh covering the hip joint, uh the knee joint, sorry and responsible for um knee extension. However, it's also covering the hip joint now, unlike the vastus, um the vastus muscles. So it's also responsible for hip flexion. All right. I hope that makes sense. So, just a little um a little bit of questions to see if you're still there. So what muscles in the anterior compartment of the thigh flex at the hip joint. So again, you put in the chart. OK. Nothing yet. But I'll let you know when someone does put an answer. Uh says rectus femoris. Good. OK. Any other muscles? Maria says iliopsoas. Yeah. Yeah. Good, good. Yeah, good. I mean, that's so, yeah. So saw us that flexes at the Rectus femoris, um the sartorius and the Pectineus really. So they all think about where they, where they originate and where they, where they uh attach to, uh they all uh go over that hip joint um aside from the vastus muscles um within the uh quadriceps, femoris muscles if you remember. Um So they're all responsible uh for um hip flexion. So the next one, what muscles in the anterior compartment of um of the thigh extend at the knee joint. So we just, we just talked about them vastus, medialis, vastus, intermedius, lateralis and medialis vastus muscles. Yeah, pretty much. So, within the cord of femoris, you've got your vastus muscles. But also don't forget the rectus femoris muscle as well because that, that still goes over the knee joint. So it's, it still uh it does hip flexion, but it also does knee extension as well. Uh Yeah. OK. And the last one, what muscles in the anterior compartment of the thigh flexes at the knee joint. So there's only one muscle, it doesn't extend it flexes. Someone said Sartorius. Yeah. Yeah. So Sartorius. OK. So fine, moving on to the medial compartment now. Um so medial, remember we're thinking about the pubis, that's the ori origin point usually for these muscles. Um So the acronym um that I used to remember uh is give Obama three apples. So it's um gracilis, um Obama for obturator externa. And in three apples, you've got your 380 doctors. Um you've got your magnus your brevis and your longus um magnus meaning great Brevis, meaning short, longus, meaning long. So we'll start off with the, the first two. So we've got the gracilis. So this, I remember the pubis we were talking about. So this will originate from the inferior pubic rami and rami just means branch. Uh So just the inferior pubic branch uh and it will insert into the medial surface of the proximal tibia, right? And you'll, you'll realize when you see the pictures. Um and the main function of all these muscles really um is ad duction. It's in the name. So it brings the femur closer to the midline. Um And with the kind of u unique um origin site of this, of this muscle, it's also responsible for flexion of the knee. So just like the sartorius, it can also flex the knee. Um the Teri externus is in the knee. Again, if you remember what we were talking about that obturator, that's where that, that's where this muscle originates from. So that, that hole that was created that obturator foramen um the externus will, will originate from and it will insert um really into the greater tranter muscle. Um Again, movement wise, it's ad duction of the hip and it's lateral rotation. So we'll have a look at the muscles. So here you've got the gracilis muscle. So that inferior pubic branch, right, inserting into the medial aspect of the proximal tibia. OK. And you can see if this would contract just what you can imagine what would happen, really. It would bring this into the midline. So that's a duction. And then also because it's that, that the ser Sertorius as well, remember it's kind of a similar to the insertion point and it's because of that unique insertion point, it would actually flex the knee, it would bring the knee backwards. All right, the obturator externus. Remember this was the obturator foramen that we were talking about. That's where it originates from and it goes, travels there and it'll travel to the creator to counter. Yeah, there. OK. So the uh originates from here and uh attaches into the uh greater tranter. And again, think about what would happen if this was contracting, it's gonna bring that, it's gonna bring that femur towards the midline. So ad duction. But also because of this, the, the orientation of the fiber, it can also laterally rotate the muscle. OK? And just here, if you can see just because it's bodied quite deep. So if you, if you can pay, um if you can remember, so this muscle right here, this would be the iliac soas muscle. So that's the SOAS major, that's the iliac and just kind of bodied beneath that you have the Teri externus muscle. OK. We'll cover the rest of these. So the, the, the last two, now we're moving to the ad doctors. So the magnus meaning grade, that's the, the biggest ad doctor and this will originate from the inferior rami of the pubis. So the inferior branch of the pubis um and then also the remi of the aium as well. And if you remember what we were talking about the posterior aspect of the femur, that rough line, the linea Aspera and the medial supracondylar line. But really, that's less. So just to remember this one magnus muscle attaches to the linea Aspera just at the back of the femur. Now function wise if we take a look here, so we can see it. So here's the A DD magnus. So you can see it's attaching, it's originating here from the anterior um uh pubis remi right. So that anterior, that inferior branch and attaching to that rough line at the back. So you had the, remember you had the pectineal line here. You've got the linear Asper here and it also inserts into this medial supracondylar line. And if you think about orientation wise and the fibers um if this would contract, it's gonna bring that knee towards the chest. So it's gonna be responsible for flexion of the hip, of course, because it's in the midline. If this is gonna contract, it's gonna bring that, that whole femur towards the midline. So it's ad duction as well and also extension. So if you have to remember one of the ad doctors, remember the magnus and are responsible for um ad duction, flexion and extension at the hip. And here you can just see just another view. So attaching at the back of the femur um an originating from the inferior pubic remi OK. And we'll just go to now you've got the maus. So now with the brevis and the longus, quite easy to remember. Um they originate from the pubis bone. Again, remember pubis bone were like a medial compartment and also attached to the linear aspera main function of these two heads is for a deduction and we'll just take a look here. So here you have it, here's the abductor, uh a doctor long sorry. And just beneath that here, um you've got the brevis head and the real the the they've got the same origin point. Um And the insertion point, the only difference is that the Brevis kind of attaches more proximately along the um along the linear Asper. Again, think about what's happening if this muscle, if these two muscles were to contract it, bring that femur into the midline. So it's a duction. He is, that's just the posterior view. So they're attaching into that the neospora at the back. OK. Last compartment. Now, the posterior compartment. So we have um the acronym by Sidney Street. So we've got the biceps femoris, right? And you've got a long head and you've got a short head similar to the upper limb. Um You've got the semitendinosis and you've got the semimembranosus and kind of if you move um if you move uh kind of medial to lateral. You've got the semimembranous, you've got the semitendinosis and you've got the biceps from more most lateral. Now, the main um see you, yeah. So the main function um of these muscles um if you think about orientation wise uh is to extend the hips to so extend it backwards procedure. So with the biceps for moti, we'll start there first. So the long head originates from. Now we're thinking, remember um the ISI, now we're talking about the posterior compartment. So that's where most of the muscles originate from. So long head originates from that ischial tuberosity. OK. That's a very important ischial tuberosity you'll see um is where all these muscles originate from. So just remember that and that short head originates from the linear aspera itself. And both of these heads will insert into the head of the fibula. So this is quite a unique thing, but most of the muscles we're talking about so far, insert into the um the tibia. But this, this muscle here, the biceps femoris um inserts the head of the fibula. Um So in some, some questions that they ask um when they're talking about, there's been an impact to the lateral aspect of the knee. Um you're thinking, OK, it could be fibula and therefore involve the, the f the function of the biceps for moris. Now, main function of this is to flex the knee and to extend the hip as we were talking about and there's also some later rotation. So if we just take a look at the fibers, so you've got this long head here. OK. Um Or originally in, as uh inserting there, sorry. And you in inserting into the, yeah, there you go. So here they're inserting into, they're originating from that um uh that is tuberosity. Um And they're um inserting there into the fibular head and orientation wise, just look at what would happen. It's crossing, it's crossing the knee, uh the hip joint and it's crossing the knee joint. So it would extend the hip backwards. Uh But it also can cause flexion of that knee. Now, moving on to the two smaller um extenders, you've got the semitendinous muscle. Um Now, this will originate again from the ischial tuberosity and it will attach to the medial surface of the tibia. Um And I just want um one of the things uh to mention, if you think about it with all kind of the knee flexion, all the muscles you'll see will in insert into kind of the medial aspect of the tibia. Um So just something to something to note. Um and again, the same uh same uh movement, knee flexion, hip extension, but this time medial rotation and that makes sense because the medial surface of the tibia. So we just have a look. So here, you've got the, the semitendinosis muscle here, inserting into the medial aspect here originating from that tibial tuberosity they all originating from the tibial tuberosity. And then you've also then got the last muscle, the semimembranous, this will originate from the ischial tuberosity and it will attach a little bit further uh proximal to the medial tibial condyle. Again, same movement, knee flexion because of bringing that knee back, hip extension, bring that hip back and then medial rotation as well. Just because given its attachment site to the medial aspect of the tibia to a better picture. Uh Yes. So you got the semimembranosus muscle here attaching to the medial aspect and you've got the semi tendinosis muscle which is a bit more lateral attaching just below and again, movement wise, it's gonna flex that knee uh and it's gonna extend that hip. Yeah. OK. With um do you have any questions for any of that? Just breathing up? No? OK. Fine. So now with nerve supply, um it's quite simple really. This is the acronym that I used to, to remember it. So I have a map of sciatica um and uh you put them in this orientation to know what and we're, we're still thinking about the regions here. So we've got the medial compartment of the thigh, anterior compartment of the thigh and the posterior compartment. Um You do the rest of the acronyms you do of sciatica. Uh And this and these kind of correspond um to the nerve supply. So with the medial compartment is supplied by the obturator nerve. OK. Most muscles. Again, it's a general rule, but it's, it's uh exam wise, that's, it's definitely true. So, medial aspect um of the thigh supplied by the obturator nerve, anterior aspect of the thigh, um supplied by the femoral nerve, posterior aspect of the thigh supplied by the sciatic nerve. Ok. So, um yeah, it's quite easy to remember really a map of sciatica um of sciatic, sorry. Um And it should help you remember the nerve supply. So we're just gonna move on to the gluteal muscles. Uh No, with the gluteal region, it can be divided superficial muscle and it can be divided into the deep muscles then. So we're gonna first begin with the superficial muscles. So with the first muscle we're gonna focus on is the gluteal maximus muscle. This will um originate from the ileum. So the posterior aspect of the ileum, um the sacrum and the coccyx as well. Uh But really just remember it's coming from that the back of the ileum. Um Now it will insert and we'll talk more about this, but it will insert into something called the iliotibial tract as well as the gluteal tuberosity of the femur. Um Now, if we just take a look here, so you can see here, this is the, this is the uh the ilium here. You've got the femur here. The gluteus maximus is look where it's originating from. It's the poster. So the anterior aspect that was where we were mentioning before and that's where the kind of the um the anterior muscle of the thigh were originating from. But the posterior aspect, that's where the gluteal maximus originates from. And it, and it can also connects here to the coccyx, coccyx and the sacrum at the back and it will attach here into this. We will talk a bit more um uh later on, but the iliotibial tract and then also the greater tranter here, we have a better view. Uh Yes. So the g that's a gluteal maximus. Um I'm thinking movement wise. Um It's gonna be extension of the thigh at the hip joint. So again, looking, looking what's happening with the orientation of the fibers, it's gonna bring that femur backwards, isn't it? So it's that extension of the hip joint and as well as that, it's gonna cause some lateral rotation as well. Ok. Now, um nerve supply very important to, you know, uh for the gluteal muscles, the gluteal maximus is innervated by the inferior gluteal nerve right now, moving on to the medius and the minimus. Um These are the two smaller muscles um of the glutes. Um Now, the medius originates from the posterior surface of the ileum. So with all these muscles without going into the nitty gritty of where it is in the ileum, they all really originate from that posterior aspect of the ileum. So just remember that um and again, inserts into the greater tranter of the femur. Um And main uh movements wise uh is responsible for abduction of the thigh, um and medial rotation and something to as high yield. And really, to remember is that the medius and the minimus both are innervated by the superior gluteal nerve, not the inferior. So, maximus in inferior gluteal nerve, medius and mini uh minimus as the superior glut uh gluteal nerve. And if you just look here, so we've got the medius here. So again, really the posterior aspect of the ilium um inserting into that into that greater um uh tranter and to be healthy. And then we've got the minimus, which is really sitting underneath that. Uh And you can think about movement wise. If this is gonna contract, it's gonna bring that femur outward. So it's abduction. Um and these two muscles medius minimus um innervated by the superior gluteal nerve maximus innervated by the inferior gluteal nerve. And here you can kind of see, I hope you can kind of realize that uh you got a lot going on here. Um But you've, well, what I want you to pay particular attention to, you've got the gluteal maximus muscle here and underneath this muscle would be the medius and underneath that would be the minimus just so you can kind of, and these are kind of the, the posterior compartment of the thigh that we were talking about here. You've got the um you've got the, the uh vastest muscles going on and we're gonna be focusing on to this now, which is the deep muscles of the glutes. So, there's two we're sorry, we're still on to the superficial muscles. Um So we've mentioned the gluts. Now, now moving on to the tensor fascia lata. Uh now, this muscle um will, it's a very small muscle. Um and it'll originate from the anterior iliac crest and this will also insert into the iliotibial band um similar to the gluteal maximus muscle. Um Now, the main function of this um 10 fascia lata um is to assist the medius and the minimus um with that abduction and that medial rotation. Um but it's, and it's also um innervated by the superior gluteal nerve. Now, so let's talk about this iliotibial tract. We mentioned it a few times now. So essentially, this is a strong band of connective tissue will which will attach the iliac crest to the tibia. So, if we take a look, so this is remember, this is a tensor fascia lata. So that small muscle here, OK. From the anterior iliac crest. And we have and this is the iliotibial tract. So it's, it's connective tissue, it's not muscle and it touches uh it's essentially connecting the iliac crest which would be here uh and attaching that into and touching that into the uh well, that would be the lateral condyle, right. And what ha what with these muscles? The tensor fascia lata, you'll see the tensor fascia lata inserts into that ileal tibial tract. And so does the gluteus maximus. So, what I want you to remember for the um iliotibial tract, there's two muscles that insert into it. It's the tensor fascia lata and the gluteal maximus muscle and the main function of it is so it, because if you can imagine if there was no um iliotibial tract, there would be the uh once the knee was extended, there would be no way to stabilize that joint, right? You would just fall over. So, the whole point of this tract is to connect these two muscles and insert it into the tibia. OK. Does that make sense to everyone? OK. If there's any question, put them in the uh in the chart. So now we're gonna, the last last section really, um we're gonna move on to the deep muscles of the glutes. So there's um four small muscle, they, they all do the same uh movement. And what I want you to remember it's lateral rotation and abduction for most of the movements. And when we look at the orientation, it'll, it'll make a bit more sense. Um not very important to remember the origin site, but if you want to and it makes it easier for you to remember, then fair enough. Um So the piriformis will originate from the anterior aspect of the sacrum. OK. And it will insert into the creator to counter of the femur. Um Now, uh same movement wise, lateral rotation abduction and the nerves really are quite easy to remember for all these muscles. Um And it's just, it's within the name. So the nerve supply is the nerve to the piriformis. Um You wouldn't have to learn the root supply or anything like that. So the piriformis remember we were saying, so it's, it's a, it's originating from that sacrum or that anterior aspect of the sacrum and inserting it into the creator tranter. And again, look at the orientation. So think about what would happen if this muscle would contract, it's gonna do lateral rotation, it's gonna bring that femur outward, isn't it? OK. And as well as that abduction, next is the obturator internus. So if you remember we were talking about the obturator externus, so they are kind of opposites of each other. So this originates uh really just remember it originates from the obturator foramen. Uh And as, and as similar to the P as it will insert into the greater to counter of the femur and save movement, lateral rotation and abduction. So if we take a look at it here, it's in, it's originating from that obturator foramen um and inserting into the greater to counter. And at the back of this obturator foramen, you would have the obturator externus muscle we were talking about. So right at the ba at the back of this uh of the back um uh sorry, at the um the anterior aspect of it, you would have that Teri to externus and they both kind of originate from that obturator foramen. So it's, it's quite easy to, to remember. Um now moving on to the um gemelli muscles. So essentially you've got the superior and the inferior portion of these muscles. Um as you can see here, now, the superior um will originate from the ischial spine and the inferior is more the ischial tuberosity. And both of these muscles again insert into the greater tranter of the femur, uh the femur um now movement wise, same thing later, rotation and abduction. So, if we have it here, so here you've got the superior Cameli muscle, ok, originating from that ischial tuberosity going into the greater trachaner. And here you have the inferior um chime muscle and here what we were talking about before you've got the obturator internus. So the obturator internus really goes in between these muscles. And again, all these muscles, if you think about it, the orientation of the fibers, if it, if it contracts, it is gonna bring that femur outwards and it gonna cause um abduction and lateral rotation. So the last one I want you to focus on um and is the quadratus femoris not to be um mixed up with the um quadriceps, femoris. And this will originate from the ischial tuberosity and will attach to that intertrochanteric crest at the back. Um If we can see. So that's it there. So that's the uh quadratus femoris. Um And there. If we talk to remember, that's the greater count, that's a lesser to counter. And that's, this would be the inter to counter crest here that's attaching to. So, in general, deep muscles of the, the glutes, what you want you to remember um is that the nerve supply is really easy to remember. Um But movement wise is responsible for lateral rotation and abduction. You, you've got it a bit more in detail for quadri uh quadris femoris. I hear, I hope you can appreciate that. So you've got the gluteal maximus muscle here and then beneath that, you've got the Medius beneath that, you've got the minimus. Um And you've got all these deep muscles here. OK. So you've got the piriformis, you've got the gli muscles, the superior, the inferior, you've got the, you got the obturator Internus muscle here and you've got the quadratus femoris muscle here. And again, think about the movement. What would happen here if this would contract? Think about the movement, what would happen here if this would contract? So it's, it's quite easy to remember. Uh If you think about it now. OK. So we're gonna move to questions now. Um I think we had some pauses or something. Yeah. Yeah, I'll launch them now. OK. So the first question um and if you, if you have any questions, please mention in the chat. Um So Abdulkarim, a 22 year old male presents to the emergency room with pain in the left knee following a twisting injury during a rugby match. He states that it has gradually swollen over the past 24 hours and he's unable to fully extend it on examination, you know, tenderness over the medial joint line, a joint effusion and the joint is held in a flex position. There is no laxity on valgus stress test. What is the most likely diagnosis? So have a think of the ligaments movements, all that put in the chart. Once you're ready, another chart, the Paul so far two people but see, bounced the wing. That's fine. Take your time. That's one minute. OK. Should we call it there? Yeah. So what's everyone said, most people said c but there's some B and E most people said see, but there's some be OK, fine. So the answer here is a medial meniscal tear. All right. So let's talk about this in detail. So first thing I want you to consider, um and the question that tells you that he's, he's got pain in the left knee following a twisting injury. So I wanna question whenever, whenever there's an uh uh a history of a rotating injury, a twisting injury in the knee, um you're thinking of potential ACL PCL tear or meniscus tear. OK. Now, the next part um of the uh of the uh history he states that it was grad had gradually swollen over the past 24 hours and he's unable to fully extend it. Now with a meniscal injury, um you have gradual swelling, ok. With an AC or a PC tear, you'll have rapid joint swelling because you have, you have hemo arthrosis, you have uh blood in the joint, so you have very quick swelling. Um So that's uh the first key point that would help you differentiate if it, is this a meniscal thing or is this a, as I say, um ACL PCL thing? Um Now, examination as well, uh kind of fits in so on examination, you know, tenderness over the medial joint line that makes, that makes it more likely that it's medial meniscal, right, la rather than lateral. Um You've got a joint effusion uh and the joint is held in that flex position, right? Because if you're extending it, if you're thinking about it, the two bones because you've got the meniscal, you've got the meniscus here, the the tube or if you're extending that knee, you're ca you're causing compression of that medial meniscus and that's gonna cause more pain. So that's why typically they'll have their joint in the flex position. Um And you could also say, why is this not a collateral ligament here? Because there's that last bit at the end here, it says that there is no laxity on the valgus stress test. So what that means? Um I don't know if you've done like knee examinations and stuff in acies and stuff. But um one of the examination things that you do, um with the knee as you put kind of um external force and you try to kind of, uh, it's called the valgus stress test. You, you push the knee um in a valgus position and you're pushing the, you're pushing the outside of the knee inwards and seeing if there's any more gi and essentially in a, in a collateral ligament here because if you remember the collateral ligaments are coming on the outside and they prevent ex uh excessive um excessive movement either medially or laterally. Um In this um test that you would do, you would see that the, the joint would move in like a lot more than normal. So the and this, this laxity, if there was lots of laxity, the joint would move in uh towards the midline a lot. And that would indicate that this is the collateral ligament here. Um Yeah. So does that make sense to everyone? No questions. So I'm guessing here. So thing to take away from this gradual swelling, meniscal injury, rapid joint swelling, most likely ACL PCL tear? Ok. Next one, Dwight, a 75 year old male presents to the emergency room after being involved in a head on car crash, he complains of severe pain in his left knee, on examination of the lower limbs. You know that the tibia displaces posteriorly on application of a force. What is the most likely diagnosis? That's one minute? Ok. So what is that? Most people said E but some D and B. Ok. So yes, most people are correct. So se is a PC tear. Um Now with this, uh with this history, um really also, and a lot of questions you'd like to ask if you see anything about like a car crash. Um because of the, where the dashboard is. Um and this happens in real life as well. Uh But when someone's in a car crash, um due to the position of the dashboard, it's uh acceleration, de deceleration injury, your, your essentially your knees are smashing into the dashboard and that will cause typically um uh AC or a PCL tear most likely a PC. So what in the history tells you that is a PCL rather than the ACL. Well, on examination, you see that the tibia displaces posteriorly on application of a force. So this is referred to um as posterior sac on examination. Um I'm thinking of a picture. Yeah. So here you can see it's quite obvious really if you have the normal, when you have the patient flexing his knee, you've lost that normal contour um of the knee joint, you've got very excessive posterior sac here. And the reason for that is remember we were talking about the, the posterior um the PCL at the back and the whole function of that um ligament is to prevent that tibia from, from moving posteriorly too much. Um So that's what tells you. Um and also examination wise again, I'm not sure if you guys have done OS stuff. Um but essentially, uh it, it, it's called a posterior draw test where you put your hand on either side of the knee, put your fingers kind of on the tibial tuberosity and push downwards. Um And in this case, you would have a lot of, you would have a lot of laxity. Uh you'd have excessive movement, posterior movement. Uh Sorry. Any questions? None. Ok. Ok. Moving on a 75 year old man is seen in the clinic with a three month history of rightsided hip pain. That is worse when going up and down stairs along with morning stiffness lasting 30 minutes. He has a past medical history of CO PD for which he was recently given a five day course of prednisoLONE following an acute exacerbation. He smokes 15 cigarettes daily and has been drinking 38 units a week after breaking up with his long term partner three weeks ago and x-rays performed, what is the most likely cause of this patient's presentation? Well, some of this information you would get in the previous, um, previous, uh, sessions that were done. That's probably enough, isn't it? Are people still left? Uh No, no, everyone sounds sorry. Uh For B in there. Some. Ok. Some B and some A I mean most B, most B, some A yes. So the answer is osteoarthritis. Um So with your osteoarthritis, remember your lost acronym? Uh, so you've got loss of joint space, osteophytes, subchondral sclerosis, subchondral cysts. Um, you can see here definite there's loss of joint space. Um, you can see the contours lost as well. You've got the cysts, you've got the sclerosis. Um, with, uh, well, actually, actually we'll go through kind of, uh, all of them. Um, so I think I, yeah, so with a avascular necrosis, I remember we were talking about, um, how if you have, uh, if you have a fracture of the femoral, uh the femoral neck slash femoral head, um, you can have interruption of that blood supply and therefore developed AVN. Ok. Um It's, it's a bit different to how it looks like in an X ray. Um With the AVN, you'll have a lot more um, distortion of the femoral head. Although you have, you do have some distortion here, um, of the femoral head and the osteoarthritis picture. It's not as, as pronounced as the, as the AVN picture here. Um But you're all, and, and with the AVN, you also wanna have the other signs of osteoarthritis. So you can see that the joint space here is relatively intact. There's no, there's no real narrowing is there. Um So that's just something um, to help you to, to try to, um, figure out which one's which, um, osteoporosis really? You would, you would do like a Dexa scan, um Iliotibial B syndrome. You wouldn't see anything in, in the X ray same uh for osteonecrosis. Um Yeah, I hope that makes sense. Ok. Question four, a 43 year old man presents to the GP with an unusual and wonky walk since a sports accident. He was involved in three weeks ago. During the examination, the GP asked the uh during examination, the GP asked the patient to stand on his left leg upon doing so. A slight pelvic drop is noted on the right side. Given the examination findings, what is the most likely affect nerve? Um So have a look at this. Have a, have a think. Um, let me know. And then when everyone's answered, we can just kind of uh just mention answer. OK, I'll let you know. OK, half the people have answered. So it's not full but they picked everything that's fine. I we'll let everyone answer then that's fine. That's I just meant if everyone had answered, that's, that's no problem. What do you mean? They picked, they picked all the answers you mean? Yeah, like 30% picked e 30% picked D 20% fixed C, 20% picked B and 10% picked A no, that's fine. That's fine. So we'll talk about it. That's everyone voted most votes is C DNE most for CD and D. OK. So the answer is C OK. So it's left superior gluteal nerve. So let's talk about this. So remember we were talking about superficial gluteal muscles. You've got the maximus, you got the medius and you've got the minimus nerve supply that you wanna remember for the medius and the minimus, it's the superior gluteal nerve. OK. With your minimus, uh your maximus, it's your inferior gluteal nerve. Now, what this uh patient has and what this examination um is called uh that the GP is doing um is called the Trendelenburg examination. Now, I don't know if you've heard of that in Aussies and stuff. Uh But yeah, let's go. So we'll, we, we see a 43 year old man. He's has an unusual and wonky walk during examination. The GP asked the patient to stand on his left leg. OK. So I'll put that in your mind, patient standing on his left leg uh upon doing so, a slight pelvic drop is noted on the right side. So what that tells you is that the pelvic drop is, I think about this one second. Yes. So here you've got the gluteus me, it's supposed to represent the medius and the minimus muscles. And we know that the main function of the medius and the minimus muscles is to abduct, right, to abduct, the um uh the, the, the femur, right, that's the across the hip joint, that's the main function of it. Now, if you have um if you have uh involvement of the, the superior gluteal nerve, and therefore you have no function of your medius and your minimus muscle, you're not able to abduct anymore. So, with this examination. If we take it, what, what happens at the GP stands uh in front of the patient. Um They'll put their hands out like this, the GP um just to support the patient, they'll get the patient to put their hands on the GP, on, on my, on your hands and you ask them to lift one leg, one by one. OK. So in this, in this sense, uh it's the, it's the left leg, we ask the patient to um lift his right leg. And what will happen is because on the left side, because these muscles are not working. Ok? The medius and the minimus muscles are not working, there's no abduction happening. Therefore, the fem the, the femur uh and the um the pelvic bone is not able to keep that muscle together because that's what you need. And what's happening here is because there's no functioning here. It's just completely, there's no, there's no tension and there's no contraction and the pelvis is dropping towards that side that you've the of the leg that you've lifted. So that's a positive Trendelenburg sign. OK. So this muscle here is not functioning. Therefore, you have no abduction going on and you need abduction because this is what happened in a normal s scenario. You need abduction to keep that pelvis, to keep that pelvis there, to keep that pelvis in line. Um So I hope that makes sense. So when, if we go back to the question then we've definitely figured out it's a superior gluteal nerve because what is the, the inferior gluteal nerve supplies the maximus? And what does the gluteal maximus do? Well, that's extension of the hip. So you wouldn't have, uh, looking at the history here. He doesn't have an issue with extension, does he? Um, so we know it's not gluteal maximus. We've decided it's the medius and the minimus. Then we've decided. Yep. We know that the superior gluteal nerve supplies the medius and the minimus. And then how do we decide, how do we decide if it's a right or left? Well, we've asked the patient to stand on his left leg and we know that he's got a pelvic drop. Now, on the right side, if we go back to the, the example, it's always the contralateral side. So we know there's weakness on the left side, the left gluteal medius, the left gluteal minimus and therefore the left superior gluteal nerve. Does that make sense to everyone? Maybe it's a bit confusing. Any questions I can see the explanation again or whatever. So there's no, there's no abduction going on. These muscles are not working. So that's why they drop, they drop onto the contralateral side. It'd be similar if it was the opposite because you need, you need contraction of this muscle to hold the femoral head towards the hip joint. And that allows the pelvis to stay at a single lane to steer, to steer um upright. Yeah, someone said it was brilliant. Thanks. I'm guessing that's your. Ok. I appreciate. Yeah, I hope that, that makes sense. Ok. Next one during a block dissection of the groin, the sartorius muscle is identified. What is the nerve supply to this muscle? It's a little bit of a fast one. hopefully it should be. Um, ok. So remember the acronym they were ta we were talking about right? Everyone's answered Now, B is the most answer. Yep. Good everyone. Yep. So it's femoral nerve. OK. And we know this because we first identified that the sartorius muscle in the anterior compartment of the thigh. And then going back to our, our uh our um uh pneumonic, we know that map of sciatica. So therefore, the anterior compartment corresponds to the femoral nerve. All right. Good stuff. Yes. So the medial obturator, anterior femoral posterior sciatic. OK. Next one, Danish a 72 year old man is getting his leg chopped off the posterior compartment. Muscles are divided which of the following muscles does not lie in the posterior compartment of the thigh. Sorry, be starting the form of anyone trying to answer. But OK. So if you remember your acronym for the posterior compartment or if you have your own acronym or whatever, everyone's answer in a split between A and C, OK. Fine. So the answer. So the question asking which of the following muscles does not lie in the posterior compartment. And so that is the quadratus femoris muscle. OK. So if we remember um uh the quadratus femoris muscle is actually one of the deep gluteal muscles. Um So if we remember the, I don't have it here, I may have not put it. Yeah. So if we remember the posterior compartment, we had the acronym uh by Sidney Street. So that's the biceps for moti, that's a semi tendinosis and the semimembranosus. OK. So that's fine. I just um just, you know, learn your compartments after I would recommend really everyone. Um especially if you, you know, you, you, you have bits that you don't know after this lecture. Um just go either go through these uh I don't think they have the lights yet. Will they either just on your own or whatever, just go through the compartment. So it's fresh in your mind and just try to um try to remember everything and um I should be helpful. OK? I think this may last year or something. So a 19 year old man is playing rugby when he suddenly noticed a severe pain in the posterior lateral aspect of his right thigh, which one of the falling muscle groups is most likely to have been injured. Yeah. So take your time with this one, think of um origin insertion points. Think about where the, the, the uh the pain is um where it is in the thigh. Most people said c but A is a runner up. OK. That sounds good. So, OK. So the answer is c correct. OK. Oh So the answer is c so remember we were talking about the, the attachment site of these muscles. So the biceps femoris um actually attaches into the fibular head, which is on the lateral aspect of the right thigh. OK. Where it is on the lateral aspect, isn't it? Um So that's how you know where, what of these uh which of these muscles is being affected because the semimembranosus and the semitendinosis are more on the medial aspect. So, um I don't know if we'll be able to go back maybe one second. I know. Hold on. So do you see here how the semimembranosus, this is, this is medial to lateral, so semi tendinosis muscles here. Then the next lateral, you've got the se uh semitendinosis and then you've got the biceps for mos and that inserts, I don't know if you can appreciate that there that inserts right into the fibular head. So up below to the posterior because it's at the back and lateral aspect of the right thigh, it's most likely of all these muscles gonna affect the biceps femoris just because these two other muscle muscles are medial. Ok. Mhm OK. So I think or no. Oh yeah. So a 34 year old man extend uh attends the accident, emergency department, complaining of hip pain around the lateral aspect of the knee. The pain started two hours ago during a hock a game of hockey uh whereby the anterior medial aspect of the patient's extended knee was struck by a hockey stick. The doctor orders a knee X ray which identified avulsion fracture of the fibular head, which muscle is most likely to cause of this patient's avulsion fracture. So everyone should get this right. I think I was supposed to change the, the order of these questions this last one. But that's good consolidation of learning. Most people said a runner up, I'd say is D OK. So the answer is the, the biceps for MS. OK. So it's the head of the fibula. That's remember we were talking about is the insertion site for both the long and the short head of the biceps. So when we talked about the sartorius, if you're saying the sartorius is more of the medial aspect of the tibia re remember? Um maybe I can show you uh uh a week, remember the sertorius. So look, the sartorius is coming and the, it's, it's inserting into the tibia uh really the medial aspect. So, uh any, any um involvement of this is not gonna cause an avulsion fracture of the fibula? Is it let see, we go back to the question. Oh No, I hope you didn't say that. Um So we see here or there is a knee x-ray which identified avulsion fracture of the fibular head. OK. So that's why it tells you it's because of all these muscles, the only one inserting into the fibular head, um is the biceps femoris muscle. So, therefore, that's what's gonna cause the avulsion fracture. Ok. Last one, you may have seen it, but that's already a 20 year old man was involved in a road traffic um collision between two cars. Both are going approximately 60 miles per hour. Once stabilized, the doctor performs a secondary survey on examination. The patient's right leg is abducted, flexed and internally rotated. He is diagnosed with a dislocation of the hip. What type of dislocation is most likely and why? This is a bit of a dodgy one, to be honest. And I'm kind of annoyed that I kinda revealed the answer but I don't know, have a, have a cold. That's a good question if I say to myself. Yeah. Mhm. Still waiting on two more people to vote, but they might have seen the answers or not enough. So we continue that all. I mean, we can, how long left? Uh No, everyone's voted now. Um Most votes is D T. OK. I hope uh as a, as a as everyone seen. Ok. Fair enough. Good. Yes. The answer is D um So how, how do we figure out it's D um with um with the ligaments that we were talking about? We know that the most important one that we have to remember is the issue of fe do I have a little diagram? Yeah. There you go. Is the issue of femoral ligament, OK. This is the most strongest ligament. And that's the, the one that you have to really remember. And the main function of this ligament if you think about the orientation, right? Uh Because we're looking at a uh if, if, if you, we're looking at a um anteriorly, right, um is to prevent hyperextension of the hip. So if the hip is coming, if you think about your own leg, if you're bringing that hip backwards backwards and you bring, you know, you're really trying to hyperextend that hip. What muscle uh if you, yeah, let me try. Oh If you think about it. So, for example, so I've got a better way of um explaining it. So you've got the acetabulum, you've got the femoral head here. OK. Now, if you bring this hip backwards, so I'm bringing my arm backwards backwards, what is preventing um this head from uh dislocating outwards and therefore causing an anterior dislocation. But it's the iliofemoral ligament, the iliofemoral ligament is there and it's, it's because it's so strong, it's preventing that anterior dislocation. That's why it's much, much more common to have a posterior dislocation because you've got this, you've got this issue of femoral ligament, which is not as strong. So what type of dislocation is most likely posterior? Ok. And for, for hips, the reason um not because the acetabulum is too shallow. The acetabulum is quite deep actually. Um The reason is because this iliofemoral ligament prevents that hyperextension of the hip. Um So therefore, it's very, it's, it's quite rare to have an anterior dislocation. Um And that's why it's posterior. So that is all. Um Thank you very much, everyone. I hope that um has helped. If you have any questions, put them down below, please, please, please, please, if you can um complete the feedback forms, it really helps me, it helps us um So we can make these sessions better for you guys. Uh That's about it. If you have any questions, let us know. Um Thank you very much. Hope that was helpful. Um All the best for the exams, it was very helpful. Thank you, her and I've just sent the feedback form onto the messages. If you fill it out, you'll also get the slides and the recording. So if you need to go over any bit, you'll be able to, you know, that you only get the slides in the recording if you follow up. Yeah. Um Well, thank you all for attending. That's the end of our session today. Ok.