Marijuana Use and Complication Risk Following Tibia Shaft Fracture Fixation.

Objectives: The aim of this study was to investigate the relationship between preoperative marijuana use and complications following tibia shaft fracture fixation.

Methods: Design: Retrospective cohort study.

Setting: Two academic Level I trauma centers.

Patient selection criteria: Adults age ≥18 years who underwent tibia shaft fracture (OTA/AO 42) fixation from 2014-2022 and had a minimum 3-months postoperative follow-up were included. Patients were considered marijuana users if they had current self-reported marijuana use or a urine toxicology screen positive for cannabinoids documented at initial presentation.

Outcome measures and comparisons: Bivariate statistics and multivariate regression were used to evaluate the effect of marijuana use on 90-day postoperative thromboembolic and surgical complications, unplanned readmissions, and emergency department (ED) visits. Complications related to fracture union were evaluated in patients with ≥ 6 months follow-up. Multivariate analysis controlled for tobacco use, open fracture, and American Society of Anesthesiologist class ≥ 3.

Results: Among 388 patients included in the study, the mean age was 37.6 years (range, 18-90), and most patients were men (66.5%). Ninety-six patients (25%) were identified as marijuana users. Marijuana users were significantly younger (30.5 years vs 40 years, P < .001) and more likely to be male (79% vs 62%, P = .002) and use tobacco currently (73% vs 31%, P < .001) than non-users. Marijuana users experienced higher rates of 90-day surgical complications (11.5% vs 4.8%, P = .030) and deep infection (8.3% vs 2.1%, P = .008) compared with non-users. No significant difference was observed between groups in the rates of thromboembolic complications, nonunion, or delayed union (P > .05). On multivariate analysis, marijuana use was not associated with odds of developing any 90-day surgical complication (OR 2.01; 95% CI 0.83-4.84) or deep infection (OR 2.97; 95% CI 0.95-9.25).

Conclusions: Preoperative marijuana use was not found to be associated with risk of thromboembolic, surgical, or fracture union-related complications in patients undergoing tibia shaft fracture fixation.

Level of evidence: Prognostic Level III.