Twenty-one Years Clinical Experience of 461 Femoral Revision Total Hip Arthroplasties with a Calcar Replacement Prosthesis

Outcomes following femoral reconstruction during revision total hip arthroplasty (THA) may be influenced by femoral deformity, fixation interface and implant type. The purpose of this study was to determine the long-term clinical and radiographic outcomes of a series of 461 femoral reconstructions with a calcar replacement prosthesis performed over a 21-year period. Multivariate analysis was performed based on age, femoral Paprosky class, implant length, modularity and mode of failure. Mean follow-up was 5.6 years. There were 18 stem revisions for an overall stem survivorship of 96.3%. Infection (n = 13) and dislocation (n = 2) were the most common indications for revision. Two stems were revised for aseptic loosening for an aseptic failure rate of 0.4%. Increased femoral deformities had higher revision rates due to all failure modes (p < 0.006). Overall complication rate was 13.4%, most commonly instability, infection and periprosthetic fracture, but most often did not lead to stem revision. We conclude that an uncemented bowed calcar replacement prosthesis has excellent clinical results in a wide range of femoral deformities, and most complications are unrelated to the femoral implant. All implants in this study have FDA approval.