Medical and recreational cannabis use in patients undergoing one- or two-level lumbar spine fusion correlated with postoperative outcomes.

Background: Cannabis use in the United States has become increasingly prevalent due to the legislation leading to decriminalization in several states; with increased social acceptance, patients are more willing to disclose cannabis use. Few studies have explored how cannabis may influence a patient's recovery following elective lumbar fusion. Therefore, the purpose of this study was to investigate how cannabis use was associated with patient recovery following elective lumbar fusions.

Methods: This retrospective single institution study included patients ages 35 through 80 years old who had undergone an elective single- or 2-level lumbar fusion between January 2021 and June 2024. Patients were placed into 1 of 3 study groups based on cannabis use, medical cannabis (MC), recreational cannabis (RC), and nonusers (NU). Differences in patient outcomes were assessed through univariate comparison and multivariate regression analyses.

Results: 627 patients were included, 129 (20.3%) admitted to cannabis use, 42 (32.5%) used medical cannabis and 87 (67.5%) used recreationally. Cannabis users were younger than NU (p<0.001) but reported increased pain (p=0.026) and required more opioids (p=0.017). Surgical site infections at 90 days (SSIs) were significantly greater in the MC group (p<0.001).

Conclusions: Cannabis use and type of usage had an impact on patient-reported outcomes, pain level, and measures of surgical success. The MC group had significantly higher opioid consumption and SSI rates at 90 days compared to nonusers and recreational groups. Therefore, this study suggests cannabis use may influence postoperative recovery following elective spine fusion. Additionally, medical cannabis users may be a high-risk group not previously identified in the literature.

Level of evidence: III.