[The morbidity of the posterior iliac crest bone graft harvesting could be an overestimated fact. Study in patients with open posterolateral lumbar fusion].

Introduction: spinal fusion is used to treat, among other pathologies, the degenerative intervertebral disc disease. Autologous iliac crest bone grafting is the golden standard treatment for increasing the rate of fusion; however, it isn't free of complications.

Objectives: to investigate whether patients who have posterior iliac crest graft harvesting and are blinded to the donor site, can identify from which side the graft was harvested, and whether the intensity of this pain is related to the amount of graft obtained.

Material and methods: prospective, experimental, randomized and comparative, single-blind study. Adult patients who underwent primary instrumented open posterolateral lumbar fusion with autologous iliac crest bone graft between July 2019 and April 2020 were included. Patients were divided into two randomized groups. The amount of graft to be harvested was according to surgical needs. The patients were asked about pain according to the visual analogue scale in the first, third and sixth months after surgery, always requesting that the most painful side be identified.

Results: a total of 44 patients (n = 23 right crest, n = 21 left crest) were analyzed. Most patients were unable to identify the side from which the bone graft was harvested, with a statistically significant difference (p-value 0.0001).

Conclusion: iliac crest bone graft harvesting is an effective and safe procedure that improves the rates of fusion without increasing the patient's morbidity.