Acute limb ischemia following closed reduction of a hip arthroplasty dislocation

Hip dislocation is a well-described complication of total hip arthroplasty (THA) and dislocation rates are substantially higher following revision hip arthroplasty. Vascular complications following closed reduction of hip dislocations are exceedingly rare, but a high index of suspicion is essential for patients with underlying vascular abnormalities. Popliteal artery aneurysms are the most common peripheral arterial aneurysms with a prevalence of 1% and they should be suspected in patients with prominent popliteal pulses. This article presents a case of an 84-year-old man with a revision total THA who sustained a posterior hip dislocation. The hip was reduced under conscious sedation using the Bigelow technique. The leg was distally neurovascularly intact based on the clinical exam immediately before and after the reduction. Over the next few hours, the foot became progressively ischemic and an urgent computed tomography angiogram revealed bilateral popliteal artery aneurysms with acute thrombosis of the aneurysm on the affected limb. The patient underwent emergent femoral popliteal bypass using a Dacron supported interpositional graft. The majority of the foot was salvaged but the toes eventually became necrotic. Direct compression of the aneurysm during reduction of the hip dislocation in conjunction with transiently decreased blood pressure from conscious sedation likely resulted in a low flow state within the artery leading to thrombosis of the aneurysm. To our knowledge, this is the first reported case of such an event. This case emphasizes the need for a high index of suspicion for vascular injuries following manipulation of limbs with underlying arterial aneurysms. Reduction maneuvers for hip dislocations should be modified to minimize compression of the popliteal fossa in limbs with vascular abnormalities. Serial postreduction neurovascular exams are essential for identification and prompt management of vascular complications.