The Association of Race/Ethnicity and Total Knee Arthroplasty Outcomes in a Universally Insured Population

BackgroundPrior studies have documented racial/ethnic disparities in the United States for total knee arthroplasty (TKA) outcomes. One factor cited as a potential mediator is unequal access to care. We sought to assess whether racial/ethnic disparities persist in a universally insured TKA population.MethodsA US integrated health system’s total joint replacement registry was used to identify elective primary TKA (2000-2016). Racial/ethnic differences in revision and 90-day postoperative events (readmission, emergency department ED] visit, infection, venous thromboembolism, and mortality) were analyzed using Cox proportional hazard and logistic regression with adjustment for confounders.ResultsOf 129,402 TKA, 68.8% were white, 16.2% were Hispanic, 8.4% were black, and 6.6% were Asian. Compared to white patients, Hispanic patients had lower risks of septic revision (hazard ratio HR] = 0.69, 95% confidence interval CI] = 0.57-0.83) and infection (odds ratio OR] = 0.42, 95% CI = 0.30-0.59), but a higher likelihood of ED visit (OR = 1.28, 95% CI = 1.22-1.34). Black patients had higher risks of aseptic revision (HR = 1.61, 95% CI = 1.42-1.83), readmission (OR = 1.13, 95% CI = 1.02-1.24), and ED visit (OR = 1.31, 95% CI = 1.23-1.39). Asian patients had lower risks of aseptic revision (HR = 0.67, 95% CI = 0.54-0.83), septic revision (HR = 0.78, 95% CI = 0.60-0.99), readmission (OR = 0.89, 95% CI = 0.79-1.00), and venous thromboembolism (OR = 0.59, 95% CI = 0.45-0.78).ConclusionWe observed differences in TKA outcome, even within a universally insured population. While lower risks in some outcomes were observed for Asian and Hispanic patients, the higher risks of aseptic revision and readmission for black patients and ED visit for black and Hispanic patients warrant further research to determine reasons for these findings to mitigate disparities.Level of EvidenceLevel III.