Adolescents undergoing spinal fusion surgery experience severe acute postoperative pain and rely on opioids for pain relief. Neurobiological and psychosocial changes during adolescence increase vulnerability to chronic pain and to substance use, placing these youth at elevated risk for developing chronic postsurgical pain as well as persistent opioid use following surgery. Recent data suggest that 5-7% of adolescents prescribed an opioid after surgery develop subsequent persistent opioid use. However, there is a gap in understanding prevalence of opioid misuse and its associated risk factors following an opioid prescription after surgery in adolescents. Thus, opioids remain the cornerstone of acute moderate-severe pain management and are commonly prescribed to adolescents for pain following surgery. This study will explore opioid misuse in a large, well characterized, previously opioid-naive sample of adolescents enrolled in a randomized controlled trial testing a cognitive-behavioral intervention for reducing postoperative pain. The objective of this study is to prospectively collect data to characterize opioid misuse following surgery and identify risk factors for postoperative opioid misuse. Youth 12-18 years of age undergoing spinal fusion surgery will report on baseline anxiety, depression, and sleep, as well as lifetime misuse of prescription opioids, pain relief preferences, and pain relief expectancies. After surgery, youth will report on daily opioid use for 14 days following hospital discharge, and report on opioid misuse at 6-months post-surgery. The aims of this supplemental award are to 1) quantify the risk of postoperative opioid use, including opioid misuse patterns and reasons for opioid misuse, and 2) identify pre-surgery risk factors, as well as beliefs, and expectations before surgery associated with short-term daily opioid use and long-term opioid misuse following surgery. This study will identify prevalence and risk factors to inform future research in this area, and identify targets for perioperative intervention to reduce problematic opioid behaviors and resulting opioid use disorders.