Simple bone cyst in cervical vertebral spinous process and laminae: Reportof a case

Simple (unicameral or solitary) bone cysts are the only true cysts of prima ry intraosseous origin. These cysts involve the metaphysis of long tubular bones such as the proximal humerus and proximal femur and, occasionally, th e proximal tibia, distal femur, patella, ilium, rib, and calcaneus. They ar e very rarely found in vertebrae, especially in the cervical vertebral spin ous process and laminae. We report a 14-year-old boy with an expansile, bub bly cystic lesion in the spinous process and laminae of the seventh cervica l vertebra. Histopathologic examination showed a cyst surrounded by thin fi brous or fibro-osseous wall without any lining epithelial cells, compatible with a simple bone cyst. As far as we know, this is the first case of simp le bone cyst involving the spinous process and laminae of a cervical verteb ra reported in Taiwan.