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

Background: 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.

Methods: 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.

Results: 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).

Conclusions: 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.