So now we'll just take a look at some of the ligaments of the knee. So what you need to remember about the ligaments is that you have collateral ligaments, cruciate ligaments and a patellar ligament. So we'll start off by looking at the collateral ligaments.
So we've got two collateral ligaments which reinforce the joint on either side. We've got a medial collateral ligament which is also referred to as a tibial collateral and we've got a lateral collateral ligament. or a fibular collateral ligament. So we'll take a look at the medial collateral ligament here.
You can see its proximal attachment on the medial epicondyle of the femur and you can see its distal attachment on the tibia. So it attaches medially on the tibia just a little bit above the insertion points of the sartorius, gracilis and semitendinosus. If I just rotate the model around...
You can see the tibial collateral ligament here and the three tendons of the sartorius, gracilis and the semitendinosus muscle. So these three tendons are collectively, the tendinous insertion of these three muscles is collectively referred to as the pes and serrinus. So these three insertions could be remembered with the mnemonic sargent, so sgt, so sartorius, gracilis and serrinus. So laterally, we've got the fibular collateral ligament or lateral collateral ligament.
This attaches on the lateral epicondyle proximally and distally, it attaches onto the lateral part of the head of the fibula. So next, we've got the cruciate ligaments. I've just rotated the model around so we're looking posteriorly at the knee.
And you can see these two ligaments. ligaments which cross over each other. So this is why they're called cruciate ligaments because the word cruciate comes from the Latin crux which means cross.
And you get other words like crucify, crucifix which just comes from the Latin cross. So you can see how these ligaments form this cross. So this is the posterior cruciate and the anterior cruciate crosses over like this.
So you can see their attachment in the inter- condylar fossa. So this ligament here is the posterior cruciate ligament and its proximal attachment is on the medial wall of this fossa. So you can see this wall of the fossa. So it's medially on the intercondylar fossa.
And the anterior cruciate ligament has its proximal attachment on the lateral wall of this intercondylar fossa. So this attaches medially on the lateral condyle and the posterior cruciate ligament has its proximal attachment posterior cruciate ligament attaches laterally on the medial. So the posterior cruciate ligament is called posterior because it attaches posteriorly on the intercondylar region of the tibial plateau. And if I rotate the model anteriorly, the anterior ligament attaches anteriorly in the intercondylar region of the tibial plateau.
I've just isolated the ligaments so you can see them a bit more clearly now. You can see how they cross over at the back here. So the function of these ligaments is to prevent anterior and posterior displacement of the tibia on the femur. You can see because the anterior cruciate ligament attaches anteriorly on the tibia, it prevents the tibia from sliding forward in this direction.
And because of the attachment of the posterior cruciate ligament, it prevents the tibia from sliding backwards. So then we've got this ligament here, the patella ligament. So this is continuous with this tendon above, the quadriceps femoris tendon. And this attaches around the sides of the patella and at the apex of the patella in it.
attaches distally to the tibial tuberosity. So you can see the tuberosity of the tibia. So you've got a medial collateral, lateral collateral, anterior cruciate, posterior cruciate and a patellar ligament that you need to know about. Lastly, I'll just talk a little bit about the joint capsule of the knee. The joint capsule of the knee has a fibrous membrane and a synovial membrane.
The fibrous membrane is reinforced by various ligaments. Medially, it's reinforced by the medial collateral ligament. It blends with fibers of this ligament and it also attaches to the medial meniscus, which is why the medial meniscus isn't very mobile. It blends with the patella ligament and attaches to the margins of the patella. And either side, you've got extensions from these two muscles, so the vastus medialis and vastus lateralis which contribute fibers to this fibrous joint capsule which are called retinacula.
So that strengthens the capsule anteriorly. And laterally, we've got the patella ligament collateral ligament, so the fibular collateral ligament. But there is actually a space between this and the joint capsule. So there's a bursa underneath the fibular collateral ligament called the fibula bursa, which separates it from the joint capsule. But it is reinforced by this tract of fibers.
So the iliotibial tract reinforces the capsule laterally. If we rotate around to the back. You can see this ligament which sort of arches over the back of the joint capsule.
This is called the oblique popliteal ligament. This is actually an extension from this tendon. This is the semimembranosus tendon which attaches onto the tibia and it gives off this ligament called the oblique popliteal ligament which reinforces the posterior aspect of the joint So lining the fibrous membrane, you've got the synovial membrane and this attaches to the margins of the articular surfaces and the outer aspects of the menisci. It's important to note that the cruciate ligaments aren't actually contained within the articular cavity.
So the synovial membrane kind of reflects back and doesn't enclose the cruciate ligaments. The synovial membrane folds in various places to form bursae. We've got the suprapatellar bursa which, as the name suggests, is a reflection of the synovial membrane which forms a bursa above the patella, so supra meaning above. We're looking laterally at the knee here. You can see the patella bone here.
This is the quadriceps femoris tendon here. And the suprapatellar bursa lies in this region just above the patella. So this is a fold of the synovial membrane.
So it also folds to form the subpopliteal recess. So this fold lies between the popliteus tendon and the lateral meniscus. So if I just fade away the muscles, we might be able to... Okay.
You can see this muscle here. This is the popliteus muscle. If I rotate it around, you can see the lateral meniscus here.
So this bursa sits sort of under the popliteus tendon between the lateral meniscus. So another thing to point out is that just underneath the patella ligament, we have a pad of fat which is called the infrapatellar fat pad. This separates the patella ligament The patella from the synovial membrane. So it sits underneath the patella ligament and separates the ligament from the synovial membrane. So a few other bursae worth mentioning.
You've got this bursae here which sits over the kneecap. It's called the pre-patella bursae, the subcutaneous pre-patella bursae. And then you've got this bursae down here which sits underneath the patella ligament. So this is called the deep infrapatellar bursae because you've also got one that sits on top of the patella ligament and that's more superficial. So this is called the superficial infrapatellar bursae.
And then you've got loads of other little bursae which sit over the tendons and ligaments, but I won't go into detail with all of those. So that's the knee joint.