Mixing Components from Different Manufacturers in Total Hip Arthroplasty: An Analysis of the American Joint Replacement Registry.

Abstract

As implants in primary total hip arthroplasty (THA) continue to evolve, surgeons may elect to combine femoral and acetabular components from different manufacturers. However, the prevalence of mixing implants in contemporary hip arthroplasty is unknown, as is the consequence that this may or may not have on implant survival. A nationwide registry was used to select patients 65 years or older who underwent primary THA between 2012 and 2021 and who had a minimum 2-year follow-up to create a retrospective cohort comparison of patients who had matched versus mixed manufacturer components. A total of 434,985 cases were identified [matched: 413,607 (95%), mixed: 21,378 (5%)]. The unadjusted and adjusted risk of all-cause revision, as well as revision for aseptic loosening, infection, instability, and periprosthetic fracture, were modeled with cause-specific Cox models. Mixing THA components increased over time from less than 2% of cases in 2012 to nearly 17% in 2021 (P < 0.001). The mixed cohort more commonly utilized dual mobility bearings (27%, 4,956 versus 7%, 24,631; P < 0.001) and triple-tapered femoral stem designs (18%, 7,185 versus 9%, 27,987; P < 0.001). After controlling for potential confounding variables, there was no difference between the two groups in terms of all-cause revision (hazard ratio (HR) 1.0, 95% confidence interval (CI) 0.9 to 1.1), revision for aseptic loosening (HR 1.2, 95% CI 0.9 to 1.6), revision for infection (HR 1.2, 95% CI 0.9 to 1.4), revision for instability (HR 1.0, 95% CI 0.8 to 1.2), or revision for periprosthetic fracture (HR 0.9, 95% CI 0.7 to 1.2). There was no difference in revision-free survival time between groups. Mixing implants from different manufacturers in primary THA does not result in an associated difference in the risk of early revision between mixed versus matched manufacturer components.