Gluteal-Sparing Approach for Posterior Iliac Crest Bone Graft

Abstract

Retrospective clinical series. Description of alternative technique for the harvesting of posterior iliac crest bone graft (ICBG) and assessment of associated morbidity. Although posterior ICBG operations are common, they are often reported to result in significant morbidity. A recent emphasis on the morbidity of ICBG has helped to fuel the costly growth in clinical use of alternatives, such as bone morphogenetic protein-2. Many studies have reported a variety of complications related to iliac crest donor sites, but the most common reported morbidity is pain and/or decreased sensation over the ICBG site. This study is a retrospective review of all patients in the practice of the senior author (T.F.A.) during the study period who received a lumbar fusion with autogenous bone harvested from the posterior iliac crest and accessed by the surgical approach described. Outcomes were assessed by a pain questionnaire determining the site of pain and its magnitude on visual analog scale. Pain on the harvested side was compared with that on the contralateral side, and overall procedure satisfaction was assessed. Statistical analysis was performed using analysis of variance, the Pearson chi2 test, and the Student t test. Any value of P < 0.05 was considered significant. Of 120 patients eligible for the study, 92 patients (77%) were available for follow-up. The patients were interviewed on an average of 24 months (+/-14 months) after their operation. The vast majority of patients (88%, n = 81) had no significant difference in pain or had less pain over the ICBG site than the contralateral side. Eleven patients (12%) experienced significantly greater pain at the ICBG site than over the contralateral side (visual analog scale difference >1). There were 7 patients (8%) in the series with significantly greater pain over the contralateral iliac crest than at the ICBG site. The likelihood of significant pain over the harvested ICBG site was not statistically greater than the likelihood of contralateral iliac crest pain (P = 0.23). One patient (1%) had sensory loss in the superior cluneal nerve distribution. There was 1 patient with an infection that involved the ICBG site and required irrigation and debridement and intravenous antibiotics. Seventy-two patients (78%) stated that they were very satisfied with the operation, 13 (14%) were somewhat satisfied, and 7 (8%) were not satisfied. Although it is difficult to directly compare our results to those reported in other studies, we conclude that the rate of significant chronic sequelae related to this method of harvesting bone from the posterior iliac crest is low. Our findings may be due to the avoidance in this technique of disruption of the gluteal musculature and preservation of the lateral wall of the ilium. The methods used in other studies to estimate the prevalence of chronic pain related to posterior iliac crest bone grafting after lumbar spinal surgery may grossly overestimate this prevalence.