Conversion of fused hips to cementless total hip arthroplasty long-term (23.5 years) functional outcome, survival and patient satisfaction

Abstract

PurposeOur retrospective study focused on long-term outcomes of converting a fused hip to a cementless metaphyseal-fitting anatomic hip system including: (1) validated clinical scores; (2) radiographic assessment; (3) impact on neighbouring joints; (4) osteolysis and revision rates; (5) complication profiles; (6) implant survivorship; and (7) patient satisfaction.MethodsWe reviewed 96 THAs in 88 patients (mean age, 42.3 years [range, 21 to 74]) who underwent conversion of fused hip through a posterolateral approach to a cementless a metaphyseal-fitting anatomic cementless total hip system, performed by one surgeon. The third generation Biolox Forte at 28 mm as the bearing surface was used in all hips. The mean follow-up was 23.5 years (range, 14 to 30 years).ResultsAt the final follow-up, the mean Harris hip score was 91.2 points (range, 52 to 100 points). Mean hip flexion was 89 degrees (range, 70 degrees to 120 degrees). Three acetabular (3%) and five femoral components (5%) that were revised. About 70 to 80% of patients expressed overall satisfaction and 66% of patients reported marked improvement in quality of life. A Kaplan-Meier survivorship analysis at 23.5 years showed a 97% survival rate (95% CI, 93 to100%) for the acetabular component and 91% (95% CI, 89 to 98%) for the femoral component.ConclusionsConversion of hip fusion to THA using metaphyseal-fitting anatomic cementless hip system appears to provide good long-term outcomes. The risk for postoperative complication including abductor dysfunction and nerve injury should be carefully discussed with patients prior to surgery.