Abstract: Introduction: Postsurgical opioid utilization may be directly and indirectly associated with a range of patient-related and surgery-related factors, above and beyond pain intensity. However, most studies examine postsurgical opioid utilization without accounting for the multitude of co-occurring relationships among predictors. Therefore, this study aimed to identify factors associated with opioid utilization in the first 2 weeks after arthroscopic surgery and examine the relationship between discharge opioid prescription doses and acute postsurgical outcomes. Methods: In this prospective longitudinal observational study, 110 participants undergoing shoulder or knee arthroscopies from August 2016 to August 2018 at Walter Reed National Military Medical Center completed self-report measures before and at 14 days postoperatively. The association between opioid utilization and both patient-level and surgery-related factors was modeled using structural equation model path analysis. Results: Participants who were prescribed more opioids took more opioids, which was associated with worse physical function and sleep problems at day 14, as indicated by the significant indirect effects of discharge opioid dose on day 14 outcomes. Additional patient-level and surgery-related factors were also significantly related to opioid utilization dose and day 14 outcomes. Most participants had opioid medications leftover at day 14. Conclusion: Excess opioid prescribing was common, did not result in improved pain alleviation, and was associated with poorer physical function and sleep 14 days after surgery. As such, higher prescribed opioid doses could reduce subacute functioning after surgery, without benefit in reducing pain. Future patient-centered studies to tailor opioid postsurgical prescribing are needed.