Local Administration of Morphine for Analgesia After Autogenous Anterior or Posterior Iliac Crest Bone Graft Harvest for Spinal Fusion: A Prospective, Randomized, Double-Blind, Placebo-Controlled Study

Abstract

Harvesting of iliac crest graft for spinal fusions is associated with a number of patients reporting residual or chronic pain at the harvest site. Various interventions, including morphine infiltration, have been proposed to minimize the associated pain. We performed a prospective, double-blind, randomized, placebo-controlled study comparing intraoperative infiltration of 5 mg morphine (treatment) versus saline (placebo) into the iliac crest harvest site for patients undergoing elective spinal surgery. Patients with myelopathy, excessive perioperative opioid use (60 mg equivalent morphine/d or more), or multilevel (>3 levels) spinal surgery were excluded. Postoperative administration of morphine (recovery room and patient-controlled analgesia) was standardized. Numerical pain scores specific for the iliac crest site were determined in the immediate postoperative period and at 3, 6, and 12 months. Of the 54 patients randomized, 47 (87%) were available for review with a minimum of 1-year follow-up. The groups were similar in baseline age, gender, and comorbidities. There was no significant difference between groups in total use of postoperative morphine during the first 24 hours (P = 0.48). Repeated measures analysis of variance demonstrated no interacting effect of group over time for hip pain at rest (P = 0.94), hip pain while moving (P = 0.90), spine pain at rest (P = 0.99), or spine pain while moving (P = 0.83). The proportion of patients reporting iliac crest pain at 1-year follow-up was the same between groups (P = 0.95). This study has demonstrated that there are no additional benefits for the use of intraoperative infiltration of morphine into the iliac crest harvest site during spinal fusions.