False aneurysm of the common femoral artery secondary to migration of a threaded acetabular component. A case report and review of the literature.

A 66-year-old woman with severe rheumatoid arthritis had revision of a protrusio acetabuli component with a threaded socket. Subsequent anteromedial migration of the socket and thread laceration of the common femoral artery resulted in a pseudoaneurysm and massive pelvic erosion seven months later. Vascular reconstruction and excisional arthroplasty were necessary. Later, gracilis and gluteal muscle flaps were swung to fill the resultant pelvic cavity. The hip was nonreconstructable. Ten months later the wound healed and the patient was ambulating in a walker. This represents a previously unreported cause of vascular injury complicating total hip arthroplasty (THA). A comprehensive review of the English and European literature illustrates the various mechanisms of vascular trauma in this setting and provides a rational basis for prevention.