Opioids are commonly prescribed for pain management in patients undergoing Posterior Spinal Instrumentation and Fusion (PSIF) surgeries. Opioids often lead to complications, extended hospitalizations, and reduced patient satisfaction. Adequate pain management requires a multidisciplinary strategy while considering the adverse effects of opioids, necessitating a personalized comprehensive pain management protocol. The objective of this work is to determine adherence to the multimodal pain management algorithm and evaluate the impact of diazepam and gabapentin on opioid usage.