Following total hip replacement, three patients had early and one had late ischemia of the ipsilateral extremity. Three required vascular surgery and one, a lumbar sympathectomy for relief of pain at rest. In each instance there had been multiple previous procedures on the same hip resulting in extensive scarring, shortening, flexion contracture, or fusion. The ischemia after total hip replacement was probably the result of interruption of critical collateral circulation about the hip or of traction on the femoral vessels tethered by scar when the short limb was lengthened or when the hip contracture was corrected. Evaluation by Doppler pressures and arteriography was helpful. Careful preoperative evaluation, early recognition of signs of ischemia, and prompt institution of appropriate management are essential to prevent this complication and to treat it adequately once it occurs.