The popliteal vein course runs alongside the popliteal artery but carries the blood from the knee joint and muscles in the thigh and calf back to the heart. Its origin is defined by the junction of the posterior tibial vein and anterior tibial vein. It drains the peroneal vein before reaching the knee joint and turns into the femoral vein when leaving the adductor canal (also known as Hunter's canal). The popliteal artery extends from the femoral artery behind the popliteal fossa which is the space behind the knee. [WP,unvetted].