Multiple Primary Joint Arthroplasties and the Risk of Periprosthetic Joint Infection: Evidence From a Large...

There is a growing number of patients who undergo multiple primary hip and knee joint arthroplasties during their lifetime. Whether patients who have multiple replaced joints are at an increased long-term risk of periprosthetic joint infection (PJI) is not known. The purpose of this study was to compare rates of PJI in patients who have more than one primary arthroplasty.

We reviewed 36,125 patients who underwent primary total joint arthroplasty at a single institution from 2011 to 2024. Patients were categorized as having one to four primary hip or knee arthroplasties. The PJI incidence was compared using Chi-square testing and binary logistic regressions, and multivariate models adjusted for sex, body mass index, diabetes, renal disease, smoking status, and Charlson Comorbidity Index. Subanalyses compared patients who had one versus two, three, and four arthroplasties.

When comparing patients who had one, two, three, or four primary joint arthroplasties, there was no significant difference in the rates of PJI between groups (P = 0.112). Multivariate analyses showed no statistically significant association between the number of arthroplasties and PJI (adjusted odds ratio for two, three, and four arthroplasties versus one: 1.34, 95% confidence interval (CI) 0.96 to 1.74, P = 0.083; 1.98, 95% CI 0.77 to 4.12, P = 0.105; 1.57, 95% CI 0.09 to 7.24, P = 0.657, respectively). Subanalyses comparing one versus three and one versus four arthroplasties showed no significant differences.

In this single-institution cohort, additional primary hip or knee arthroplasties did not appear to substantially increase PJI risk. These findings suggest a potential trend that requires confirmation with larger, prospective, multicenter, or registry-based studies. Nevertheless, these results provide preliminary evidence to inform patient counseling and guide future research on the risks of multiple arthroplasties.