Popliteal artery entrapment syndrome. Report of two cases.

We treated two patients with popliteal artery entrapment syndrome. In one, the popliteal artery was entrapped and obstructed in its abnormal course around the medial head of the gastrocnemius muscle, which was inserted into the femur laterally and cephalad (type II in Delaney's classification). In the other patient, the popliteal artery followed a normal course but was compressed laterally by the medial head of the gastrocnemius muscle, which was aberrantly inserted into the femur considerably higher and more lateral than usual, and was occluded. This could not be fitted into Delaney's or Insua's classification. Arterial reconstruction was successful with an autovein graft in the former case and an in situ bypass graft in the latter. We suggest a modification of type IV in Delaney's classification, so that when the popliteal artery is compressed by an aberrant muscular or tendinous structure in the popliteal fossa it can be included.