Posterior Knee Anatomy

The diamond-shaped popliteal fossa is bordered proximally by the hamstring tendons and distally by the gastrocnemius muscle. The sciatic nerve splits into the common peroneal nerve and tibial nerve just before entering the popliteal fossa. The popliteal vein is deep to the nerves. The popliteal artery is deeper and is closest to the capsule. The popliteal artery has variations that are surgically significant. The posterior knee capsule has two named thickenings, the oblique popliteal ligament (a tendinous continuation of the semimembranosus tendon) and the arcuate ligament (which forms an arch over the popliteus tendon).