Persistent sciatic artery: case report, anatomy, and review of the literature.

We report the case of a 64-year-old woman with an aneurysm of a left persistent sciatic artery presenting with arterial insufficiency from distal embolization. Treatment was exclusion of the aneurysm and femoropopliteal bypass after distal embolectomy with a Fogarty balloon catheter. We reviewed 71 cases in the literature to define characteristics of this anomaly which has many synonyms: including persistent sciatic artery, persistent axial artery, ischiopopliteal trunk. The persistence of the sciatic portion of the embryonic dorsal axial artery and failure of development of anastomoses with the ventral femoral network results in the anomaly. The persistent sciatic artery was "complete" in 75% of cases. In this configuration, it arises from the internal iliac artery, leaves the pelvic cavity through the lower part of the greater sciatic foramen caudad to the pyriformis muscle, reaches the posterior compartment of the thigh and continues as the popliteal artery. In 35% of cases, the artery is aneurysmal with a pulsatile mass in the buttock or a complication of the aneurysm. Arteriography required for diagnosis of the mass leads to discovery of the anomaly in many cases. The treatment of choice is exclusion followed by femoropopliteal vein bypass.