Cannabis Use and Postoperative Risks: A Comprehensive Analysis of Medical Complications Within 90 Days Following Ankle Fracture Fixation

Category: Ankle; Trauma Introduction/Purpose: As medical and recreational cannabis use continues to increase in prevalence across the United States, it is important to understand how cannabis can impact health. Though prior studies have shown that cannabis use can result in delayed bone healing, there is a paucity of literature examining the relationship between cannabis use and postoperative medical outcomes following fracture fixation. Therefore, the purpose of this study was to investigate the relationship between cannabis use and the incidence of medical complications within 90 days of surgical fixation of ankle fractures. Methods: A retrospective review of a national insurance claims database was performed from 2010 to 2022. Patients who underwent open reduction and internal fixation (ORIF) procedures for medial malleolus fractures, lateral malleolus fractures, distal fibula fractures, bimalleolar fractures, and trimalleolar fractures were identified using CPT codes. Of those patients, those with established diagnoses of cannabis use disorder, cannabis dependency, or cannabis addiction were identified using ICD-9 and -10 codes. This cannabis cohort was matched 1:4 on the basis of age, sex, and Charlson Comorbidity Index (CCI) to a control cohort without a history of cannabis use to remove potential confounding upon comparison. Demographic and comorbidity profiles, as well as medical and surgical post-operative outcomes were compared using Chi-square tests. Results: Out of 788,702 patients undergoing ankle fracture open reduction and internal fixation (ORIF) during the study period, 46,105 had documented cannabis use. Cannabis cohort, compared to controls, exhibited significant differences: younger age (mean 38.8 vs. 52.7 years; p< 0.001), lower comorbidity-burden (mean CCI 1.58 vs. 1.68; p< 0.001), and a higher proportion of male patients (51.1% vs. 33.2%; p< 0.001). Following age, CCI, and sex matching, patients with cannabis use histories showed a significantly increased incidence of medical complications within 90 days post ankle fracture ORIF. Cannabis users displayed elevated rates of various complications compared to matched controls, including pneumonia, deep venous thrombosis, pulmonary embolism, myocardial infarction, stroke, surgical site infection, cardiac arrest, acute kidney injury, urinary tract infection, sepsis, and hypoglycemia (all p< 0.001). Conclusion: Cannabis use is associated with increased incidences of many serious medical complications within 90 days of ankle fracture fixation procedures. These results underscore the importance of eliciting cannabis use history during preoperative patient evaluations so that physicians and patients can be better informed about the increased postoperative risks they may face, and so tailored perioperative care can be appropriately implemented. Further, these results emphasize the need for further research on the molecular mechanisms of cannabis to explain interactions that may predispose heavy cannabis users to this profile of adverse surgical outcomes.