Survival and Clinical Outcomes at 30 to 35 Years Following Primary Total Hip Arthroplasty With a Cementless Femoral Stem Fully Coated With Hydroxyapatite.

BACKGROUND:The purpose of the present study was to update and report clinical outcomes and survival of primary total hip arthroplasty using a cementless double-tapered titanium fully hydroxyapatite-coated stem at a follow-up > 30 years. METHODS:The outcomes of this series of 347 primary total hip arthroplasties were already published at a follow-up > 25 years, during which only 12 stems were revised. Since then, there were two additional stem revisions, bringing the total to 14 stem revisions (all of which also required cup revision). Patients still living with the original stem were assessed using the modified Harris Hip Score and patient satisfaction (very satisfied, satisfied, dissatisfied, and very dissatisfied). Revision incidence was calculated using the Kaplan-Meier (KM) method and Cumulative Incidence Function (CIF) at 35 years. RESULTS:At a mean follow-up of 33 years (range, 31 to 35 years), 32 patients (34 hips) were still living with the original stem. Their mean modified Harris Hip Score was 86 points (range, 46 to 100) and all patients (100%) were very satisfied or satisfied with surgery. The revision incidence at 35 years considering (a) stem revision for any reason was 9.5% using KM and 4.5% using CIF; (b) stem revision for aseptic loosening was 3.1% using KM and 2.1% using CIF; and (c) reoperation or revision of any component for any reason was 45.3% using KM and 26.3% using CIF. CONCLUSION:The present study has demonstrated excellent survival at 35 years for a cementless double-tapered titanium fully hydroxyapatite-coated stem. LEVEL OF EVIDENCE:Level IV, Retrospective cohort study.