One-surgeon versus two-surgeon single-anaesthetic bilateral total knee arthroplasty: revision and mortality rates from the Australian Orthopaedic Association National Joint Replacement Registry

Abstract Background Outcomes following one-surgeon single-anaesthetic sequential bilateral knee arthroplasty (seq-BTKA) compared to two-surgeon single-anaesthetic simultaneous bilateral knee arthroplasty (sim-BTKA) are largely unknown. The current study compared revision rates and all-cause mortality following seq-BTKA versus sim-BTKA using data from the Australian Orthopaedic Association National Joint Replacement Registry. Methods Seq-BTKA and sim-BTKA procedures recorded within the Registry between 1 September 1999 and 31 December 2018 were analysed for subsequent revision and patient mortality. Cumulative percent revision (CPR) and cumulative percent survival (CPS) were determined using the Kaplan-Meier method. Revision and mortality rates for sim-BTKA and seq-BTKA were compared using Cox proportional hazards models, adjusting for age and sex. Results Included in the analysis were 27,480 seq-BTKA’s and 471 sim-BTKA’s. There was no difference in the cumulative percent revision was between the two groups (hazard ratio 1.23, 95% CI 0.82, 1.85). Cumulative percent patient survival was not significantly different between the two groups (hazard ratio 1.20, 95% CI 0.93, 1.54). Conclusion Revision rates and mortality were similar for seq-BTKA and sim-BTKA. Investigation of additional outcomes such as complications not requiring revision, pain, function and cost is required to comprehensively understand the relative merits of each procedure.