Safety of posterolateral approach with a polished cemented stem and a modular dual mobility implant in patients over 75 years old

Background: With increasing life expectancy, total hip arthroplasty (THA) is increasingly performed in patients over 75 years, a population at higher risk of perioperative complications. This study assessed the safety and short-to mid-term outcomes of a standardized THA strategy in elderly patients using a posterolateral approach, a polished cemented stem, and—when indicated—a modular dual mobility (DM) cup. Methods: This retrospective multicenter study included patients >75 years who underwent primary THA with a cemented polished femoral stem and posterolateral approach (2017–2023). Group A received a modular DM cup, while Group B received a fixed-liner acetabular component. Clinical outcomes (Oxford Hip Score, VAS satisfaction) and complications were recorded. Survivorship was evaluated using Kaplan–Meier analysis in best- and worst-case scenarios. Results: 642 THAs were analyzed (Group A: 460; Group B: 182). Groups were comparable in age and sex distribution. Dislocation rate was significantly lower with DM (0.7% vs 2.75%; p = 0.045). No differences were observed in infection, aseptic loosening, periprosthetic fracture, reoperation, readmission, or mortality. Postoperative OHS was similar, while patient satisfaction (VAS) was higher in Group A (93.0 ± 7.0 vs 81.9 ± 14.2; p < 0.001). Kaplan–Meier analysis demonstrated excellent survivorship in both cohorts, without significant differences. No intraprosthetic dislocations or DM-related mechanical failures occurred. Conclusion: THA using a posterolateral approach and a polished cemented stem is safe in patients over 75 years. Modular DM cups reduced dislocations and improved patient satisfaction without increasing complications. Their selective use may be advantageous in elderly, high-risk patients. Further prospective long-term studies are warranted. Level of evidence: Level III, retrospective cohort study.