Purpose: To compare the risk of total hip arthroplasty (THA) revision between patients with rheumatoid arthritis (RA) and patients with osteoarthritis (OA), using data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).
Methodology: This cohort study analysed 3,269 RA and 389,450 OA patients undergoing primary THA recorded in the AOANJRR, from 1999 to 2023. Cumulative percent revision (CPR) rates were calculated using Kaplan-Meier methods. Hazard ratios (HRs) were determined through Cox proportional hazard models adjusted for age and sex. Outcomes included all-cause revision and revision for dislocation, infection, aseptic loosening, and periprosthetic fracture (PPF).
Results: RA is associated with a higher all-cause revision (HR 1.26; 95% CI 1.08–1.48; p=0.004), revision for infection (HR 1.38; 95% CI 1.00–1.89; p=0.047), early aseptic loosening (0-3 months; HR 2.66; 95% CI 1.37–5.15; p=0.003), and dislocation (HR 1.78; 95% CI 1.35–2.33; p<0.001). However, no differences were observed in revision for PPF.
Conclusion: RA is a complex multisystem disease that, despite therapeutic advances, continues to be associated with serious adverse post-operative risks including revision for infection, aseptic loosening, and dislocation. Increased risk of revision for infection emphasises the importance of multidisciplinary team involvement to optimise the balance between disease control and infection risks in RA patients on potentially immunosuppressant therapies. An absence of current strategies to prevent early aseptic loosening in RA highlights a need for further research. Increased risk of revision for dislocation suggests surgeons should consider dual mobility THR in RA patients to improve post-operative outcomes.