Hospital Volume and Postoperative Infections in Total Knee Arthroplasty.

BACKGROUND: The purpose of this study was to evaluate the associations of hospital volume with revision surgery for infection and superficial incisional infections.
METHODS: A review of 12,541 primary total knee arthroplasties (TKAs) at a large integrated health system from 2014 to 2017 was conducted. Sixteen hospitals were classified as low-volume, medium-volume, or high-volume hospitals according to the mean number of TKAs/year (<250, 250-500, and >500, respectively). Thresholds were guided by percentiles and the literature on volume-outcome relationships. Medical records were reviewed for revision surgery for infection and superficial incisional infections during a mean 2-year review period. Multivariate analyses, adjusted for clinical and patient characteristics, were performed to evaluate the association between hospital volume and infection.
RESULTS: The overall rate of revision surgery for infection was 0.7% (n = 82), and the overall rate of superficial incisional infection was 2.6% (n = 324). After accounting for potential confounders, hospital volume was not found to have a significant association with revision surgery for infection when comparing high-volume and low-volume hospitals (odds ratio, 1.615; 95% confidence interval, 0.761-3.427; P = .212) as well as when comparing high-volume and medium-volume hospitals (odds ratio, 1.464; 95% confidence interval, 0.853-2.512; P = .166). Moreover, the risk of superficial incisional infection at high-volume hospitals was similar to that at low-volume (P = .107) and medium-volume (P = .491) hospitals.
CONCLUSION: Infection outcomes are quality metrics that are frequently used to compare hospitals including those of varying volumes. Using contemporary thresholds, this study found that infection rates after TKA at high-volume hospitals are comparable to low-volume and medium-volume hospitals.