Cementless short stem total hip arthroplasty in patients older than 75 years: Is it feasible?

Background In recent years, the indication for cementless short stem total hip arthroplasty (THA) has been widened to elderly patients as they might proft by the advantages of the short-curved implant design as well. Therefore, this study was conducted to evaluate the clinical and radiological outcome of a cementless short stem in elderly patients (≥75 years) compared to a young control group (≤60 years). Methods A retrospective cohort of 316 THAs performed between 2014 and 2017 was prospectively examined. In all patients a cementless, curved short stem and press-ft cup (Fitmore® stem; Alloft®/-S cup; both ZimmerBiomet, Warsaw, IN, USA) were implanted via a minimally-invasive anterolateral approach. Clinical and radiological outcome as well as rate of complications and revision were assessed. Results In total, 292 patients have been included for analysis of complications and revisions (Øfollow-up: 4.5 years) and 208 patients for clinical and radiological outcome (Øfollow-up: 4.4 years). Complication rate was signifcantly increased in elderly patients (13.7% vs. 5.8%, p=0.023), while the revision rate was increased without statistical signifcance (5.2% vs. 2.2%, p=0.169). Periprosthetic fractures occurred signifcantly higher in the elderly patients (5.2% vs. 0.7%; p=0.026). Both groups showed a comparable clinical outcome in the Harris Hip Score (93.7 vs. 91.9; p=0.224), Oxford Hip Score (44.5 vs. 43.7; p=0.350), Forgotten Joint Score (81.7 vs. 81.5; p=0.952) and WOMAC (7.4 vs. 9.3; p=0.334). Conclusion Cementless short stem total hip arthroplasty shows a comparable clinical and radiological outcome in patients over 75 years of age compared to younger patients under 60 years of age. However, cementless shorts stem THA shows an increased rate of overall complications and periprosthetic fractures in elderly patients over 75 years of age. Cemented fxation of the femoral component should be considered in patients over 75 years of age. Level of evidence III Case-controlled study. Trial registration Observational study without need for trial registration due to ICMJE criteria.