Bilateral persistent sciatic arteries complicated with acute left lower limb ischemia.

Persistent sciatic artery (PSA) is a rare congenital malformation. In the early embryonic stage, the sciatic artery is the major blood supply for the lower limb bulb and is later replaced by the iliofemoral artery as the limb develops. Its failure to regress, sometimes associated with femoral arterial hypoplasia, and therefore becoming the dominant inflow to the lower extremity is called PSA. This anomaly is often associated with a higher rate of aneurysm formation or thromboembolic complications causing lower extremity ischemia. Here, we describe a 79-year-old male patient who presented with acute left lower extremity ischemia. He was treated initially with conventional embolectomy through inguinal and popliteal incisions. The bilateral PSA with thrombosed aneurysms was not identified at first on computed tomographic angiography. It was later diagnosed intraoperatively due to the discontinuity of the superficial femoral artery and popliteal artery found with embolectomy catheter, and was managed successfully with ePTFE graft bypass. Careful interpretation of the imaging study may be helpful in preoperative diagnosis.