Methods: This paper followed the Preferred Reporting Items of Systematic Reviews and Meta-Analyses guidelines. Two independent reviewers searched PubMed, Embase, and the Cochrane Library to find studies assessing the impact of resident involvement on patient outcomes in orthopedic surgery cases. Nine patient characteristics (age, sex, body mass index, American Society of Anesthesiologists physical status classification, history of chronic obstructive pulmonary disease, congestive heart failure, diabetes, hypertension, and smoking) were compared between cohorts to investigate participant similarity. Twenty-seven outcome variables potentially impacted by resident involvement were compared via meta-analysis. Variables include length of stay, mortality, graft or prosthesis failure, and operative time. Study quality was assessed using both the Newcastle-Ottawa Scale for cohort analysis and the Agency for Healthcare Research and Quality standards. As several of the included papers relied on data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP), sensitivity analysis was done to assess for patient overlap between papers. The ACS NSQIP reports 30-day patient outcomes.

Results

Forty-two studies met inclusion criteria, and thirty-seven of those were amenable to meta-analysis. The highest quality studies were those that employed propensity scoring in their patient analysis. Pooled estimate of only the high-quality evidence demonstrated little negative effect of resident involvement in orthopedic surgery. Longer operative times (mean difference [MD], 31.68 minutes; [95% confidence interval (CI)], [9.03, 54.33]) and increased odds of getting a blood transfusion of =5 units of packed red blood cells (odds ratio [OR], 1.96; [95% CI], [1.46, 2.63]) were the only variables to remain statistically significant when considering these high-quality studies. Considering only the propensity scored papers, five studies analyzing operative time and transfusion were identified. These studies included 10,864 patients (5,449 in the “resident-involved” arm and 5,415 in the “no resident-involved” arm) and 9,306 patients (4,670 in the “resident-involved” arm and 4,636 in the “no resident-involved” arm), respectively. Sensitivity analysis of the five papers, done for both transfusion and operative time, revealed no overlap between patient populations.

Conclusions

When only high-quality studies are considered, resident involvement in orthopedic surgery has no negative effect on patient outcomes. The only significant effects are increased operative time and number of transfusions, which are expected when considering time needed for intraoperative education and learning since longer operative times may necessitate an increased number of transfusions. However, more research into the effect of resident involvement on transfusions is needed. Finally, further studies are needed to determine the long-term effects of resident involvement.