During a period of six years, 765 consecutive patients were treated by the trauma service at Allegheny General Hospital for closed mid-shaft femur fractures that were a component of their injury complex. Thirty-one patients underwent angiography of the involved extremity for indications including loss of pulses in eleven and large hematomas or deformities of the thigh in the remainder. Ten patients (1.3%) were found to have acute vascular injuries. In nine patients there was an intimal flap of the superficial femoral artery (SFA), and in one, a pseudoaneurysm. Two patients had injuries of the femoral nerve. Three patients had no other associated major injuries (Injury Severity Score range, 10–19). Twelve months after the initial injury, one patient developed an arteriovenous fistula of the SFA. Detailed, repeated physical examinations, early utilization of angiography, and intensive follow-up by the trauma surgeon or orthopedic surgeon of patients with closed mid-shaft femur fractures should lead to early recognition of this potentially serious association.