Does Surgical Trainee Participation Affect Infection Outcomes in Primary Total Knee Arthroplasty?

OBJECTIVE: To evaluate whether the involvement of surgeons-in-training was associated with increased infection rates, including both prosthetic joint infection (PJI) and surgical site infection (SSI), following primary total knee arthroplasty (TKA). DESIGN: This was a retrospective review of outcomes following primary total knee arthroplasty. Surgeries were divided into two groups: (a) attending-only and (b) trainee-involved. Association with PJI and SSI were evaluated with univariate analysis and multivariate analysis to adjust for sex, age, body mass index (BMI), Charlson Comorbidity Index (CCI), year of surgery, operative time, and hospital/surgeon volume. SETTING: A single, large North-American integrated healthcare system between January 1, 2014 and December 31, 2017. PARTICIPANTS: A total of 12,664 primary TKAs with a minimum of one-year (mean of 2-years, range 1-4.5) follow-up were evaluated. RESULTS: Residents and fellows were more likely to participate in cases with longer operative times (p<0.001) than the attending-only group. A significant difference existed on univariate analysis between the trainee-involved group and attending-only group for PJI incidence (p=0.015) but not for SSI (p=0.840). After adjusting for patient- and procedure-related features, however, neither PJI nor SSI were independently associated with trainee involvement (PJI: p=0.089; SSI: p=0.998). CONCLUSIONS: Trainee participation did not directly correlate with increased infection risk, despite their association with longer-operative times and increased medical complexity. Further approaches to mitigating the risk of SSI and PJI for patients with increased comorbidities and in complex TKA cases, which demand longer operative times, are still required.

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.