To evaluate the patient-reported expectations regarding cannabis for pain following musculoskeletal (MSK) trauma and patients' perceptions and attitudes regarding its use. A cross-sectional retrospective survey-based study. Three orthopaedic clinics in Ontario (Level-1 trauma center, Level-2 trauma center, rehabilitation clinic). Adult patients presenting to the clinics from January 24, 2018, to March 7, 2018, with traumatic MSK injuries (fractures/dislocations and muscle/tendon/ligament injury) were administered an anonymous questionnaire on cannabis for MSK pain. Primary outcome measure was the patients' perceived effect of cannabis on MSK pain, reported on a continuous pain scale (0%-100%, 0 being no pain, and 100 unbearable pain). Secondary outcomes included preferences, such as administration route, distribution method, timing, and barriers (lack of knowledge, concerns for side effects/addiction, moral/religious opposition, etc.) regarding cannabis use. In total, 440 patients were included in this study, 217 (49.3%) of whom were female and 222 (50.5%) were male, with a mean age of 45.6 years (range 18-92 years, standard deviations 15.6). Patients estimated that cannabis could treat 56.5% (95% CI 54.0%-59.0%) of their pain and replace 46.2% (95% CI 42.8%-49.6%) of their current analgesics. Nearly one-third (131/430, 30.5%) reported that they had used medical cannabis and more than one-quarter (123/430, 28.6%) used it in the previous year. Most felt that cannabis may be beneficial to treat pain (304/334, 91.0%) and reduce opioid use (293/331, 88.5%). Not considering using cannabis for their injury (132/350, 37.7%) was the most common reason for not discussing cannabis with physicians. Higher reported pain severity (β = 0.2/point, 95% CI 0.1-0.3, P = 0.005) and previous medical cannabis use were associated with higher perceived pain reduction (β = 11.1, 95% CI 5.4-16.8, P < 0.001). One in 3 orthopaedic trauma patients used medical cannabis. Patients considered cannabis could potentially be an effective option for managing traumatic MSK pain and believed that cannabis could reduce opioid usage following acute musculoskeletal trauma. These data will help inform clinicians discussing medical cannabis usage with orthopaedic trauma patients moving forward.