Intra-articular benign osteoblastoma of the acetabulum: a case report.

The acetabulum is an unusual location for benign osteoblastoma, usually seen in adolescents and young adults. This article reports a case of an intra-articularly expanding benign osteoblastoma of the acetabulum in a 6-year-old boy. The diagnostic and surgical features of the disease in this unusual location at this young age are discussed. Excisional biopsy and curettage of the lesion followed by bone grafting resulted in healing of the acetabular lesion without acetabular dysplasia, but with a resultant coxa magna.