Long-Term Mortality Trends After Revision Total Knee Arthroplasty

Background: Long-term mortality following primary total knee arthroplasty (TKA) is lower than the general population. However, it is unknown whether this is true in the setting of revision TKA. We examined long-term mortality trends following revision TKA. Methods: This retrospective study included 4907 patients who underwent 1 or more revision TKA between 1985 and 2015. Patients were grouped by surgical indications and followed until death or October 2017. The observed number of deaths was compared to the expected number of deaths using standardized mortality ratios (SMR) and Poisson regression models. Results: Compared to the general population, patients who underwent revision TKA for infection (SMR, 1.45; 95% confidence interval [CI], 1.33-1.57; P < .0001) and fracture (SMR, 1.16; 95% CI, 1.00-1.34; P = .04) experienced a significantly higher mortality risk. Patients who underwent revision TKA for infection and fracture experienced excess mortality soon after surgery which became more pronounced over time. In contrast, the mortality risk among patients who underwent revision TKA for loosening and/or bearing wear was similar to the general population (SMR, 0.95; 95% CI, 0.89-1.02; P = .16). Aseptic loosening and/or wear and instability patients had improved mortality initially; however, there was a shift to excess mortality beyond 5 years among instability patients, and beyond 10 years among aseptic loosening and/or wear patients. Conclusion: Mortality is elevated soon after revision TKA for infection and fracture. Mortality is lower than the general population after revision TKA for loosening and/or bearing wear but gets worse than the general population beyond the first postoperative decade.