Cannabis Use and Postoperative Complications After Primary Achilles Tendon Repair: A Propensity Score-Matched Cohort Study.

Background: Recreational and medical cannabis continue to increase substantially, yet its impact on musculoskeletal healing has not been investigated extensively. Hypothesis/Purpose: The purpose of this study was to evaluate the association between preoperative cannabis use and postoperative complications after primary Achilles tendon repair. We hypothesized that cannabis users would demonstrate higher rates of complications and revision surgery. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective cohort study of patients who underwent primary Achilles tendon repair, as reported in the TriNetX database. Patients were stratified into 2 cohorts based on documented cannabis use. Propensity score matching (1:1) was utilized to balance confounding baseline demographic characteristics and comorbidities. Primary outcomes were revision surgical repair and reinjury rate at 1 and 2 years, while other medical and surgical complications were also evaluated at 90 days and 6 months postoperatively. Statistical analysis was performed in the TriNetX system. Continuous variables were reported as the mean ± standard deviation. Categorical variables were reported as frequencies and percentages, with risk ratios and Kaplan-Meier analysis recorded for appropriate variables. Results: After propensity score matching, 1088 matched pairs were analyzed with appropriate covariate balance, all with standardized differences <0.10. Cannabis users demonstrated significantly higher rates of wound dehiscence at 90 days (4.32% vs 2.29%; Conclusion: These findings suggest that cannabis use may play a role in early wound healing without compromising long-term tendon structural repair. These data can help surgeons educate patients about potential increases in the risk of wound complications and prompt consideration of preoperative counseling and enhanced postoperative wound surveillance.