Posterior Thigh and Popliteal Fossa – Overview of Arterial Supply to Lower Limb

00:00 This is known as the cruciate anastomosis. Now let’s move on to the posterior thigh and the popliteal fossa. First of all, here we can see we have the posterior thigh.

00:11 We can see we’ve got the large sciatic nerve passing down. And we can also see some of these perforating arteries that I’ve talked about. So we can clearly see some of the perforating arteries passing through adductor magnus. We’ll come back to them. And then we can follow now onto the posterior surface of the knee, the popliteal fossa. We can see the popliteal fossa running down the posterior aspect of the knee. And within it, we have the popliteal artery. So let’s look at the posterior thigh. First, we have perforating arteries, three or four, and these come from profunda femoris. They pierce adductor magnus and to the posterior compartment of the thigh. And as they pierce, they typically send superior and inferior branches to join up with adjacent perforating arteries. So you can see you’ve got a perforating artery here. It will send an ascending branch up. It will send a descending branch down. Superiorly, we have one coming down from inferior gluteal. So superiorly, we have inferior gluteal supplying the more proximal aspect of these thigh muscles.

01:25 And inferiorly, the popliteal artery will pass up as well to supply the more distal aspect of these hamstrings. But the main supply is going to be via these perforating arteries coming from profunda femoris and passing through adductor magnus. You can also see that they will supply the sciatic nerve as they go on. Here, we have a specific blood vessel to the sciatic nerve, the artery of the sciatic nerve, and that is coming from the inferior gluteal.

01:59 But more distally, they’ll come from these perforating arteries. If we now look at the popliteal artery, it is the direct continuation of the femoral artery within the popliteal fossa. So the femoral artery passed through the adductor canal. It exited the canal via the hiatus, and it became the popliteal artery. Here, we can see the popliteal artery within the popliteal fossa. This popliteal artery is important. It goes on to supply the leg and the foot, and it also supplies the knee joint by way of genicular arteries. So we’ll come to those in a moment. But first of all, we can see the popliteal artery terminating by this anterior and posterior tibial artery. Here, we’ve got the anterior tibial artery, and we’ve got the posterior tibial artery. And this occurs at the inferior border of popliteus. Here, we can see popliteus muscle, and we’ve got the inferior border of popliteus muscle, and that is bifurcating here into anterior tibial and posterior tibial.

03:10 If we look at the popliteal artery itself before it bifurcates, it gives rise to five genicular arteries. And these supply the joint capsule and ligaments of the knee joint. We have two superior and we have two inferior, and we differentiate the two superior arteries into lateral and medial, and the same for the inferior. So we have superior lateral, superior medial, inferior lateral, inferior medial. Here, we can see the popliteal artery giving rise to the superior lateral and the superior medial genicular arteries. We can then see them giving rise to the inferior lateral and inferior medial genicular arteries. We can see they’re giving muscular branches that go and supply the heads of gastrocnemius here. But here, we can see those four genicular arteries. We also have what’s known as the middle genicular artery. The middle genicular artery is important as it specifically goes in to supply the joint capsule. And these genicular arteries form the genicular anastomosis as they curve round onto the anterior aspect of the knee to supply the entire knee joints.

04:28 They’re also going to receive descending branches from the femoral and the lateral circumflex arteries. So we can see here, we have a descending genicular artery. And that’s contributing to the genicular anastomosis. This is important as it provides additional blood supply if the popliteal artery was to become compromised in some way. Now let’s