LAUSR

Dear Editor, I read with great interest the article of Medina and colleagues in a recent issue of the journal [1]. The authors performed an observational study on 997 patients undergoing outpatient orthopaedic surgery and concluded that marijuana use was an independent factor associated with less pain intensity in the operative site. The authors should be applauded for performing a well-designed study in an important topic (e.g., acute pain) in patients undergoing orthopaedic surgery [2, 3]. The need to improve post-operative recovery by reducing moderate-to-severe post-operative pain makes the topic very important in peri-operative medicine [4, 5]. Nonetheless, there are some critical points that need to be clarified by the authors to determine the validity of their findings. First, it is unclear if the authors adjusted their findings for the type of surgery because different orthopaedic procedures may cause a substantial variation on post-operative pain. Second, it is also not clear if the authors adjusted their analysis for the intra-operative or post-operative use of nerve blocks as this can also affect the primary outcome. Last, the authors should have presented opioid consumption. Marijuana use decreases opioid side effects (e.g., nausea and vomiting); therefore, it is possible that patients who used marijuana had less pain because they used more opioids [6]. I would welcome comments by the authors as this would help to further support the findings of this important study. Compliance with ethical standards