The muscles of the thigh are encased in a very thick and tough layer of deep fascia that we discussed in Exercise Fourteen. The fascia lata encloses the thigh and also has a modified portion, the iliotibial tract, that provides the distal attachment for the gluteus maximus and the tensor fascia lata. The collagen fibers of the iliotibial tract or band are lined up parallel with one another, and give the band a distinct tendon like appearance.

Like the upper limb, the cutaneous veins of the lower limb are extremely variable. Usually, however, there exists a great saphenous vein that lies on top of the fascia lata. This long vein begins on the dorsum of the foot, runs anterior to the medial malleolus, and ascends the medial side of the calf and thigh. The great saphenous vein ends by running through an opening of the fascia lata - the saphenous opening - and empties into the femoral vein.

The external iliac artery supplies the lower limb with arterial blood. As it passes under the inguinal ligament, its name changes to the femoral artery.

In the upper or superior aspect of the thigh, the femoral artery gives rise to important branches that supply the hip and thigh region. The major branch of the femoral artery in the upper thigh is the deep femoral or profunda femoris. This artery in turn gives rise to two circumflex arteries that supply the hip joint region; a descending branch that supplies the anterior thigh and perforating branches that supply the medial and posterior thigh.

The femoral artery continues inferiorly, coursing medially under the cover of the sartorius muscle in the so- called subsartorial or adductor canal. It eventually pierces through the adductor magnus at the adductor hiatus, and wraps around to the posterior aspect of the thigh. When the femoral artery passes through the adductor hiatus, its name changes to the popliteal artery and is found on the posterior side of the knee in the popliteal fossa.