Cannabis users who are candidates for knee or shoulder surgery should discuss post-operative risks with their health care providers. Arthroscopic surgery is minimally invasive surgery that uses a small camera device to guide the process. Arthroscopic procedures are commonly used to repair knee, shoulder, and hip injuries.
A study presented at the Scientific Forum of the American College of Surgeons (ACS) Clinical Congress 2022 found a higher post-operative infection rate associated with cannabis consumers. The research team from the University of Chicago also found higher rates of deep vein thrombosis (DVT) among cannabis consuming patients, although the researchers considered this percentage not statistically significant.
The researchers identified 1,113,944 knee and 747,938 shoulder arthroscopy patients from a national insurance claims database called PearlDiver. It is one of the first retrospective studies of patients with cannabis dependence who underwent knee or shoulder arthroscopy for the postoperative complications. The individuals included in the study underwent surgery for the treatment of deep vein thrombosis (DVT), pulmonary embolism (PE), and infection after surgery. 21,823 of these individuals had a diagnostic code for marijuana dependence included in their claim, indicating daily or chronic cannabis use and/or reliance on cannabis for relieving pain, stress, and/or mental distress.
The cannabis using cohort had increased rates of infection and DVT. The PE rate stayed the same. The infection rate increased from 0.7% to 1.7% for the shoulder arthroscopy group while the DVT rate rose from 0.2% to 0.4%, and PE stayed at 0.2%. The rates of infection increased from 1.1% to 2.6%, the DVT rate rose from 0.2 to 0.3%, and PE stayed at 0.3% in the knee arthroscopy group.
This study provides a better understanding of the relationship between cannabis dependence and potential postoperative complications. Cannabis users can take precautionary steps such as limiting or ceasing use weeks before surgery.