Short-stem hip arthroplasty in Australia and the Netherlands: a comparison of 12,680 cases between the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the Dutch Arthroplasty Register (LROI).

Background and purpose We compared the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the Dutch Arthroplasty Register (LROI) regarding patient, prosthesis, and procedure characteristics as well as revision rates for uncemented short-stem total hip arthroplasties (THAs). Patients and methods All THAs with an uncemented short-stemmed femoral component performed between 2009 and 2021 were included from the AOANJRR (n = 9,328) and the LROI (n = 3,352). Kaplan–Meier survival analyses and multivariable Schemper’s weighted Cox regression analyses with data from 2009–2021 and 2015–2021 were performed with overall revision as endpoint. Results In Australia, the proportion of male patients (51% vs. 40%), patients with ASA III–IV score (30% vs. 3.7%), BMI ≥ 30.0 (39% vs. 19%), and femoral heads of 36 mm (58% vs. 20%) were higher than in the Netherlands. Short-stem THAs in Australia and the Netherlands had comparable 10-year revision rates (3.4%, 95% confidence interval [CI] 2.9–4.0 vs. 4.8%, CI 3.7–6.3). Multivariable Cox regression analyses with data from 2009–2021 showed a higher risk for revision of short-stem THAs performed in the Netherlands (HR 1.8, CI 1.1–2.8), whereas the risk for revision was comparable (HR 0.9, CI 0.5–1.7) when adjusted for more potential confounders using data from 2015–2021. Conclusion Short-stem THAs in Australia and the Netherlands have similar crude and adjusted revision rates, which are acceptable at 10 years of follow-up.