 Good day everybody. This is Dr. Sanjay Sanyal, Professor Department Chair. This is the second part of the demonstration of the femur. This time we're going to focus on the muscle attachments and the actions thereof. So what we have done, we have held up the left femur up in an upright position. So this one that you see here, this is the head of the femur, this is the neck of the femur, this is the greater trochanter of the femur. Let's focus on the muscle attachments of the greater trochanter of the femur. These are the insertions. The blue are the insertions, the red will be the origin. This is the insertion of the gluteus medius, gluteus minimus. The gluteus medius, the gluteus minimus, they come vertically down and they get inserted onto the greater trochanter. And these muscles, they're very important in abduction of the hip and they're important in medial rotation of the hip. If this muscle is paralyzed, then the person will not be able to hold the pelvis straight when standing on the leg of the paralyzed side and that is called the Trenland Berg sign. So that is what we see about the insertion of the gluteus medius and the gluteus minimus on the greater trochanter. Now I'm going to turn the femur and we are looking at the posterior aspect. Now we can see posterior aspect. This is the posterior aspect of the neck of the femur and we can see certain muscle attachments attached to the tip of the greater trochanter. We have the pyriformis. The pyriformis is one of the deep gluteal muscles and the pyriformis takes origin from inside the inner surface of the sacrum comes out through the greater stratum for ramen and it gets inserted into the tip of the greater trochanter. If you look here where my finger is located and this place here, this is trochanteric fossa and this gives insertion to the operator externus and the operator internus. The operator internus is also one of the deep gluteal muscles and it is responsible for external rotation. Now let's come further lower down. We see this insertion here. This is called the quadratubuckle. It is on the approximately the middle of the inter-trochanteric crest on the posterior aspect. This gives attachment to the quadratus femoris which takes origin from the ischial tuberosity. It's like a quadrangle and gets inserted onto the quadratubuckle. This is also one of the deep gluteal muscles and this is also responsible for lateral rotation of the femur. Let's come further down. We can see certain further muscle attachments here. This is the lesser trochanter and this gives insertion to the ilio suas tendon. This is a very important insertion which is the muscle of the anterior compartment and this is responsible for fraction of the hip. Between the ilio suas tendon and the hip joint there is a bursa where my finger is located and that is called the ilio suas bursa. Now I'm focusing on the posterior aspect of the femur, the shaft of the femur. We can see multiple linear lines. The most prominent line is where my finger is tracing. This is known as the linear aspera and we can see that the linear aspera is splitting downwards into two lines here. These are respectively referred to as the lateral and the medial supra-condyler lines and this is the perpendicular surface of the femur. Let's go up. We find the linear aspera also divides into a lateral and a medial line above. The linear aspera itself is a thick ridge and it's got a lateral lip and a medial lip. So the lateral lip of the linear aspera gives attachment to the vastus lateralis and also gives attachment to the short head of the biceps femoris and the lateral lip also gives attachment to the lateral intermuscular septum. So the lateral intermuscular septum covers the vastus lateralis from the posterior aspect and then it goes further laterally and it merges with the iliotibial tract on the lateral aspect. When we trace the line up, as I said, it divides into a lateral and a medial. The lateral lip, you see this swelling here, this is called the gluteal tuberosity and this gives attachment to the deep one-fourth of the fibers of the gluteus maximus muscle on the gluteal tuberosity. Now let's take a look at the rest of the linear aspera. The linear aspera gives it insertion to the upper part. This is called the pectinial line, the attachment of the pectinous muscle. Then we have the attachment of the adductor brevis. Approximately the middle one-third gives attachment to the adductor longus and adductor magnus takes the major part of the attachment here. Attached to the medial lip is also the vastus medialis and the medial intermuscular septum. So between the vastus medialis and the adductor magnus, deep inside runs the profunda femoris vessels. So that is the location and after that the profunda femoris pierces through the attachment of the retro magnus and goes and becomes a perforating arteries. Now let's come further lower down. We are looking at the perpendicular surface. We can see the two femoral condyles here and this is the intercondyler fossa. This forms part of the knee joint, the posterior aspect and it is covered by the capsule of the knee joint. We can see certain muscle attachments here also. There's the lateral condyle, there's the medial femoral condyle. So this is the attachment of the medial head of the gastropameus and this is the lateral head of the gastropameus and above that we can see this is the attachment of the plantaris muscle. This elevation that we see here, this is called the adductor tubercle which is present on the medial side on the medial condyle. This adductor tubercle gives attachment to the adductor tendon which is the hamstring component of the adductor magnus and this forms the medial boundary of an opening here where my finger is located which is called the adductor hiatus and through this adductor hiatus the femoral vessels, they come and they enter the propitial fossa and they change the name from femoral to propitial. So this is the location of the adductor hiatus. The femoral propitial artery can get entrapped at the adductor hiatus. This adductor tubercle can be felt in a normal person and this is where we can tap with the knee hammer to elicit the adductor reflex. To come further, we see another muscle in taking origin from here. This is one of the origins of the propitius muscle. The other origin of the propitius muscle being from inside the knee joint that is from the lateral meniscus and this is the insertion of the propitius muscle but that is in the leg so we shall not talk about that. So these are the aspects that we can see on the posterior aspect of the femur. Now I'm going to turn the femur. Now we are looking at the anterior aspect of the femur and we can see the most of the anterior aspect is quite featureless because it gives attachment to a very big muscle here and this is the vestus intermedius. It takes origin from the front of the femur and it merges with the quadriceps tendon. Deep to the vestus intermedius, we have two slips of muscle which are referred to as the articularis genu. The articularis genu are partly merged with the fibers of the vestus intermedius and they take partly origin from the front of the femur and they get inserted onto the suprapatellar bursa and their function is to pull the suprapatellar bursa away during extension of the knee to prevent it from getting trapped. Medially we can see this muscle here. This is part of the origin of the vestus medialis and laterally is the origin of the vestus lateralis that we can see up here. So the front of the knee is entirely occupied by the quadriceps muscles and all of them get inserted by the quadriceps tendon onto the base of the patella which is located here. So these are pretty much all the muscles that we can see attached to the femur. The significance of all these muscles is that if there's a fracture of the sharp of the femur which can happen from a very serious injury to the thigh, the fragments of the femur they invariably displace and they override because the pull of these strong and heavy muscles. This is the plane x-ray to show fracture of the mid-sharp of femur. Please note the overriding of the fragments. Therefore it's very important to give initial traction. Bring the ends in alignment but they will not remain in alignment. They have to be fixed by open reduction and internal fixation. This is a fracture sharp of femur that has been treated with intra medullary nail and hip screw. So that is the point which I wanted to mention about the other aspects of the femur. Thank you very much for watching. Dr. Sanger signing out. Please like and subscribe. If you have any questions or comments, please put them in the comment section below. Have a nice day.