Brodie's abscess of the posterior ilium: a rare cause for low back pain in children.

Brodie's abscess of the pelvis is very rare in healthy children. It can be missed because of its varied presentation. We present an 11-year-old boy who presented with low back pain. Investigations revealed a well-defined lesion in the posterior ilium. He underwent open biopsy and debridement. At the end of the final follow-up, he was asymptomatic and there was no recurrence. We present this case for the rare site of Brodie's abscess and for its unusual presentation as low back pain.