Now we’ll move on, to look at the principal veins, arteries and nerves in the region of the knee. We’ll begin where we saw them last, just below the hip. We’ll follow them to just below the knee.
With the main artery and vein, there’s a change of name that we need to understand. In the upper and middle thigh, they’re known as the femoral vessels, but below the adductor hiatus they’re called the popliteal vessels. The same vessels, just a different name.
Here’s the thigh, with the skin removed, and a strip of subcutaneous fat taken out so that we can see the long saphenous vein. Here it’s in the middle of its course from the ankle to the top of the thigh. To see the femoral vessels we’ll remove the superficial fat, and deep fascia.
Here are the femoral artery and vein at the point where we saw them last, disappearing beneath the sartorius muscle. To follow their course, we’ll remove sartorius, and also gracilis.
Here’s vastus medialis, here’s adductor longus, with adductor magnus behind it. The femoral vessels pass beneath the roof of the adductor canal, and through the adductor hiatus. To see where they emerge, we’ll remove semi-membranosus and semi-tendinosus, and go round to the back. Here are the vessels emerging behind adductor magnus. They’re now known as the popliteal artery and vein.
A little above the knee the popliteal vessels are joined by the sciatic nerve. At the back of the knee, the popliteal artery lies deep to the nerve, and to the popliteal vein. To see the artery better, we’ll go to a different dissection in which the muscles are intact, and the nerve and the vein have been removed.
Above the knee, which is just here, the popliteal artery gives off these two superior genicular arteries, lateral, and medial. At the knee it gives off these branches, to the two heads of gastrocnemius; and below the knee it gives off these two inferior genicular arteries, medial, and lateral. The popliteal artery then disappears deep to the two heads of gastrocnemius. We’ll see where the vessels go from there, in the next section.