A case report: periprosthetic acetabulum fracture with combined pelvic ring injury.

Periprosthetic fractures of the acetabulum are largely underreported in the literature, none of which describes the management of such injuries associated with a pelvic ring injury. Our case report discusses our approach to managing a periprosthetic both-column acetabulum fracture associated with an open-book pelvic ring injury. Instead of a revision total hip arthroplasty, we chose to perform an open reduction internal fixation to maintain sufficient bone stock for future revision, if necessary. At 18 months postoperative follow-up, the patient was ambulating independently and had sufficient range of motion that was comparable to the contralateral hip.