Two patients with popliteal artery entrapment including one bilateral were operated on in the Cardiovascular and Thoracic Surgery Unit at the UCL between January 1987 and February 1988. Both patients complained of severe intermittent claudication. One of the entrapments resulted from internal deviation of the vessel. The two others were secondary to excessively external insertion of the medial head of the gastrocnemius muscle. These preoperative findings correlated with preoperative CT scan. A section of the medial head of the gastrocnemius resulted in complete liberation of the popliteal artery in each case. In addition, a popliteal thromboendarterectomy was performed in one patient and a lumbar sympathectomy in the other