Poplitea

Poplitea is the Latin term used in anatomy to denote the popliteal region behind the knee, most often encountered in the names Arteria poplitea (the popliteal artery) and Vena poplitea (the popliteal vein). The popliteal fossa is a shallow, diamond-shaped hollow at the back of the knee. It is bounded superiorly by the tendons of the biceps femoris laterally and the semimembranosus and semitendinosus medially, and inferiorly by the medial and lateral heads of the gastrocnemius. The floor is formed by the femur’s popliteal surface, the knee joint capsule, and the oblique popliteal fascia; the roof contains skin and the popliteal fascia, with the small saphenous vein draining into the popliteal vein.

Contents and course: The principal contents are the popliteal artery and popliteal vein, which accompany each other through the fossa. The sciatic nerve typically bifurcates within or just above the fossa into the tibial nerve (medial) and the common peroneal (fibular) nerve (lateral); these nerves lie superficial to the vessels, with the common peroneal nerve curving around the fibular neck more laterally. Lymph nodes and fat are also present. The popliteal artery usually terminates by dividing into the anterior tibial and posterior tibial arteries near the lower border of the popliteus muscle.

Clinical relevance: The popliteal region is clinically important because it is susceptible to traumatic injury and vascular disease, including popliteal artery aneurysm and deep vein thrombosis, as well as nerve entrapment or compression. Baker’s cysts can compress vessels or nerves in the fossa. Palpation of the popliteal pulse and imaging are commonly used in evaluating knee and lower-leg conditions.