Low-Volume Surgeons Operating at High-Volume Hospitals Have Low Rates of Periprosthetic Joint Infection After Hip and Knee Arthroplasty.

Background: The relationship between surgeon and hospital case volumes and postoperative risk following total hip arthroplasty and total knee arthroplasty (THA and TKA) has been described independently. This study aimed to assess the risk of periprosthetic joint infection (PJI) following primary TKA and THA to determine if lower volume surgeons operating at higher volume centers would have lower rates of complications compared to lower volume surgeons operating at lower volume hospitals.

Methods: A health care database was used to retrospectively identify all primary and elective total joint arthroplasties from October 2015 to December 2021. Using restricted cubic splines, high-volume hospitals were defined using Markov chain Monte Carlo simulation, which identified a volume beyond which PJI rates no longer decreased significantly with increasing hospital volume. A similar methodology was used to identify low-volume surgeons operating in high- and low-volume hospitals. There were 605,254 patients who underwent total joint arthroplasty (THA: 37.71%; TKA: 62.29%) by low-volume surgeons (< 57 THAs and < 68 TKAs) identified and divided into high- and low-volume hospital cohorts. High-volume hospitals were defined as > 508 THA and > 812 TKAs per year, and low-volume hospitals were defined as < 145 THAs and < 243 TKAs per year. Multivariable models accounting for potential confounding covariates were created to determine the odds of PJI between cohorts.

Results: After taking confounding variables into account, low-volume surgeons at high-volume hospitals had lower rates of PJI relative to their counterparts at low-volume hospitals (THA 0.67 versus 0.80%, adjusted odds ratio = 0.69 [95% confidence interval = 0.54 to 0.88], P = 0.002; TKA 0.51 versus 0.69%, adjusted odds ratio = 0.73, [95% confidence interval = 0.61 to 0.87], P = 0.007).

Conclusions: Increasing institutional case volume may mitigate the increased risk of PJI associated with low annual surgeon case volume.