Total Hip Arthroplasty for the Treatment of Failed Acetabular Fractures

Abstract

There is an increasing prevalence of older patients with acetabular fractures and high conversion rate of operatively and nonoperatively treated geriatric acetabular fractures to total hip arthroplasty. These cases should be approached as a revision total hip arthroplasty with many similar challenges including previous hardware, scarring, heterotopic ossification, malunion, nonunion, acetabular bone loss, avascular necrosis of the femoral head, and potential occult infection. The patient should undergo a detailed physical examination documenting gait, neurovascular status of the lower extremity, leg-length discrepancy, and previous surgical incisions. Imaging should consist of AP pelvis, AP and lateral of affected hip, Judet radiographs, and CT scan of the pelvis with 3-D reconstruction. Review of preoperative radiographs and CT scan will allow templating and evaluation of the leg-length discrepancy, heterotopic ossification, previous hardware placement, bone stock, and acetabular defects. Prior to surgery it is important to rule out occult infection of previously failed ORIF of acetabular fractures. A complete blood count (CBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) should be obtained. If a high index of suspicion for infection remains, then a hip aspiration should be obtained and sent for cell count with differential and culture. The decision regarding surgical approach is often dictated by surgeon’s preferred approach, previous surgical approach used, retained hardware, location of heterotopic ossification removal, and acetabular defects that need to be addressed. These cases have unique challenges related to optimal acetabular cup fixation and stability often requiring structural bone graft, antiprotrusio cage, jumbo cup with distraction, or combined ORIF. There is a high risk of complications compared to primary total hip arthroplasty including increased risk of dislocation, infection, and heterotopic ossification and decreased survivorship of implants. As a result, total hip arthroplasty after failed acetabular fracture should be performed in specialized centers with adult reconstruction and orthopedic trauma specialists.