Cemented Femoral Stem Design Is Not Associated with Risk of Revision After Total Hip Arthroplasty in Patients Aged ≥ 65 Years: An Analysis of the American Joint Replacement Registry.

Abstract

Cemented femoral fixation for total hip arthroplasty (THA) in those aged ≥ 65 years has potential benefits. However, few resources exist to assist in selecting cemented femoral implant designs. We examined the associated risk for all-cause revision, risk of periprosthetic femoral fracture, and aseptic loosening based on a modern classification of cemented femoral stem designs. An analysis of primary THA cases in patients aged ≥ 65 years was performed with American Joint Replacement Registry (AJRR) data linked to Centers for Medicare and Medicaid Services data from 2012 to 2023. Patient demographics, revision or open reduction and internal fixation (ORIF) for periprosthetic femoral fracture, and revision for aseptic loosening were recorded. We identified 20,484 primary THAs with cemented stems that were classified via a modern classification. There were 5,437 (26.5%) type I (taper-slip) and 14,796 (72.2%) type II (composite beam) stem designs. Cause-specific Cox proportional hazard models with competing risk of death were used to evaluate the association of cemented stem design with all-cause revision, revision or ORIF due to periprosthetic femoral fracture, and revision for aseptic loosening while adjusting for potential confounders. Compared to those who had type I (taper-slip) designs, those with type II (composite beam) designs were not associated with increased risk of all-cause revision hazard ratio (HR) = 1.3 (95% confidence interval (CI): 1.0 to 1.7, P = 0.06), revision or ORIF for periprosthetic femoral fracture HR = 0.8 (95% CI: 0.4 to 1.7, P = 0.6), and revision for aseptic loosening HR = 1.6 (95% CI: 0.8 to 3.4, P = 0.2). Cemented stem designs were not associated with risk of all-cause revision, revision/ORIF for periprosthetic femoral fracture, or revision for aseptic loosening in patients aged ≥ 65 years. As such, orthopaedic surgeons should be aware that the selection of specific cemented stem designs may not necessarily reduce the risk of revision.