摘要:Background: Locus of pain control (LPC) is characterized by the behavior of people coping with their health problems, as a result of their own actions (internal control) or external factors or other people (external control). This parameter can be associated with medication adherence, in addition to other psychosocial factors that may also influence this behavior. This study was performed to investigate the influence of the LPC on medication adherence in patients undergoing an orthopedic procedure. Subjects and methods: We conducted a prospective cohort study on patients who attended an orthopedic clinic for arthroscopy treatment. The patients’ LPC and pain intensity data were obtained on the day of admission through the use of the LPC scale and the visual analog scale (VAS), respectively, both being validated tools. After arthroscopic surgery, the patients received drug prescriptions and were reassessed after 15 days regarding treatment adherence, using the Morisky test. A P -value <0.05 was considered statistically significant. Results: We assessed 79 individuals from both the internal LPC group (n=35) and external LPC group (n=44) and found that there were no group differences in sex, affected limb, cause of injury, repetitive strain injury, duration of pain, or pain intensity. However, there was a higher proportion of patients in the external LPC group that adhered to the prescribed medication compared with the internal LPC group ( P >0.01). Conclusion: The results showed that among patients who underwent an orthopedic procedure, there was a higher adherence rate to prescribed medication in the external LPC group compared with the internal LPC group.