Much higher re-revision rates and mortality following septic revision total knee arthroplasty compared to meta-analyses

This study investigates re-revision and mortality rates following septic revision of total knee arthroplasty (TKA) using registry data from Germany. An observational cohort study was conducted using data from the German Arthroplasty Registry (EPRD), consisting of 15,372 revision TKAs. Cumulative incidences of re-revision and mortality for septic and aseptic revision-TKAs were analyzed over a seven-year follow-up (2015 to 2022). Kaplan-Meier estimates were employed to determine re-revision rates and cumulative mortality probabilities after revision TKA. The re-revision rate within the first year following septic revision TKA was 21.7% (95% CI 20.3 to 23.1), compared to only 7.1% (95% CI 6.6 to 7.6) for aseptic revisions. Notably, 74% of all re-revisions for septic revision TKA occurred within the first year. Cumulative mortality within the first year after septic revision TKA was 4.9% (95% CI 4.2 to 5.7), rising to 28.5% (95% CI 24.2 to 33.2) after seven years. In contrast, aseptic revision TKA had lower mortality rates, with 2% within the first year and 16% within seven years. After multiple previous knee revisions, re-revision rates increased to over 47%, and mortality to 30% for septic revisions. Registry data revealed nearly twice the re-revision rates for septic revision TKA compared to single-centre studies, reflecting real-world outcomes in Germany. Septic revision TKA has a threefold higher re-revision rate in the first year and double the mortality rate compared to aseptic revisions. Given the high risk in the first postoperative year, optimizing perioperative procedures is crucial to reducing the burden of septic revision TKA.