A Quality Initiative for Posterior Spinal Fusion in Adolescent Idiopathic Scoliosis (AIS): Liposomal Bupivacaine With Dexamethasone Use Results in Substantial Reduction in Inpatient Opioid Use.

Abstract

Enhanced recovery after surgery (ERAS) pathways have improved postoperative outcomes for adolescent idiopathic scoliosis (AIS) patients undergoing posterior spinal instrumented fusion (PSF). Liposomal bupivacaine (LB) intramuscular infiltration has emerged as a potential adjunct for opioid-sparing analgesia. This quality initiative evaluates the impact of incorporating LB with intravenous dexamethasone and eliminating patient-controlled analgesia (PCA) within an ERAS pathway. A retrospective review was conducted of AIS patients aged 10 to 18 years who underwent PSF at a single pediatric tertiary-care center between 2019 and 2025. Three postoperative analgesia protocols were compared: (1) intrathecal morphine (ITM) with PCA, (2) intravenous methadone with PCA, and (3) LB infiltration with dexamethasone without PCA. The primary outcome included cumulative inpatient opioid consumption standardized to morphine milligram equivalents (MME/kg). Secondary outcomes included length of stay (LOS) and pain scores. A total of 159 patients were analyzed (ITM: n=88; methadone: n=36; LB/Dex: n=35). The LB/Dex group demonstrated a substantial reduction in cumulative opioid use compared with ITM and methadone cohorts (0.56±1.43 vs. 4.13±0.90 and 5.32±1.41 MME/kg; P=0.04). LOS was significantly shorter in the LB/Dex group (2.11±0.15 d) compared with ITM (2.80±0.09) and methadone (3.06±0.14; P<0.001). Eighty percent of LB/Dex patients were discharged on postoperative day 2 versus 42% (ITM) and 27.8% (methadone). Pain scores were comparable across groups, with no clinically significant differences despite the absence of PCA in the LB/Dex cohort. Incorporating LB with dexamethasone and removing PCA within an AIS ERAS pathway significantly reduces opioid use and shortens LOS without compromising pain control following PSF. These findings support LB/Dex as an effective opioid-sparing strategy for AIS patients undergoing PSF and highlight the value of multimodal analgesia in optimizing recovery and promoting opioid stewardship. Level III.