Acetabular Augments Used in Revision Hip Arthroplasty: Minimum 10-year Follow-up of Implant Survivorships, Functional Scores, and Radiographic Outcomes

Abstract

BackgroundAcetabular bone loss is a major challenge in the setting of revision total hip arthroplasty (THA). Porous tantalum augments have emerged as a viable solution to acetabular bone loss in revision THA. The purpose of this study was to evaluate the survivorship, clinical, and radiological outcomes of these implants. MethodsWe identified 104 augment implants from our retrospective chart review of revision total hip arthroplasty from June 2003 to July 2013. Of these patients, 75 (72.1%) were women, mean age at surgery was 66.2 years (range, 27 to 87); and a mean follow-up was 13.2 years (range, 0.25 to 18.2). Kaplan-Meier survival analysis was performed, with failure defined as revision for aseptic loosening of the acetabular reconstruction. ResultsThere was significant improvement in the Harris Hip Score from 40.0 to 77.3 (P < 0.001) and the Oxford Hip Score from 14.9 to 36.3 (P < 0.001). Survivorship for failure due to aseptic loosening was 98.8% (95% CI [confidence interval] 96.4 to 100) at 24 months with 60 hips at risk, and 90.4% (95% CI 83.0 to 97.8) at 60 and 120 months with 38 and 18 hips at risk, respectively. The overall rate of all complications was 34 (32.7%). Of these complications, 21 (20.2%) required repeat revision surgery. The revision rate due to aseptic loosening of the augment, infection, dislocation, aseptic loosening of the femoral component, reconstruction failure, and heterotopic ossification was 7 (6.7%), 5 (4.8%), 4 (3.8%), 2 (1.9%), 2 (1.9%), and 1 (0.96%), respectively. ConclusionTreatment of acetabular defects during revision THA using porous tantalum augments provides acceptable implant survivorship and favorable clinical outcomes at mid-term (5-10 year) and long-term (>10 year) follow-up.