POPLITEAL artery entrapment syndrome refers to intermittent claudication, usually in the young, produced by an anomalous course of the popliteal artery medial to the medial head of the gastrocnemius muscle. In this position, the artery is traumatized and repeatedly compressed between bone and contracting muscle. As a result, the vessel may undergo degeneration with aneurysmal dilation, plaque formation, thromboses, and eventually occlusion.
The popliteal artery normally courses between the medial and lateral heads of the gastrocnemius artery. In this syndrome, it passes medially across the posterior aspect of the medial gastrocnemius, separated from its companion vein, then courses laterally and anteriorly to rejoin the vein and descend normally into the leg. The medial course of the artery varies depending on the locus of insertion of the medial head of the gastrocnemius on the femoral metaphysis. Rarely, the artery, although following a normal course, is compressed by an aberrant segment of