A CLINICAL STUDY OF PROBLEMS FOLLOWING BONE GRAFT HARVEST FROM THE POSTERIOR ILIAC CREST

Abstract

When bone graft is harvested during posterior spinal fusion, approaching the posterior iliac crest parallel to the superior cluneal nerves (SCN) can result in vascular, neurological, sacro-iliac joint and other complications. In a previous study, in 30% of adult cadavers I found that branches of the superior cluneal nerves were within the safe zone of 65 mm from the posterior superior iliac spine along the posterior iliac crest.

Following posterior spinal fusion, 24 male and 12 female patients, ranging in age from 14 to 55 years, were reviewed. Follow-up ranged from nine months to 15 years. Data collected included personal and social details, surgical indications, neurological status, harvest site and postoperative complications. Patients were excluded if neurological injury affected assessment of the posterior iliac crest. Specifically the harvest site was examined for pain, SCN injury, sacro-iliac joint instability or pain, and any other complications.

In 15 patients the incision was parallel to the SCN nerve. One had scar pain and one had scar hypertrophy. Three patients (20%) had SCN damage symptoms in the form of numbness, transient in two and permanent in one. There were no sacro-iliac joint or complex regional pain syndrome (CRPS) problems. Two cases of superficial wound sepsis resolved. The other 21 patients had incisions transverse to the SCN. Six (28%) had persistent scar pain and eight (38%) had symptoms of SCN damage (numbness or hyperaesthesia). None had CRPS, sacro-iliac joint symptoms or sepsis. Incisions parallel to the SCN led to less morbidity than incisions along the posterior iliac crest.

Bone graft substitutes are increasingly being used in the developed world, but if thoughtful surgical techniques can minimise graft site morbidity, the posterior iliac crest is a cost-effective source of autologous bone.