[Spinal localization of a solid aneurysmal cyst. Clinical, radiologic and histopathological aspects].

An 8 year old child with a "solid" aneurysmal cyst of L4 posterior arch was investigated by straight films, bone scintigraphy and CT scans. The suggested diagnosis had been a benign tumor, probably an osteoblastoma. Initial histopathology results were in favor or a non ossifying fibroma or a chondromyxoid fibroma, this lacking concordance with the usual epidemiology of primary spinal tumors in children. A description is given of the histologic characteristics of this new histopathologic entity first described by Sanerkin in 1983.