Study design: A case report.
Objectives: To illustrate a rare case of histologically confirmed solitary bone cyst involving the spinous process of C7.
Summary of background data: A solitary bone cyst involving the spine is very unusual. Although four cases of a solitary bone cyst in the spine have been reported in the literature, the current authors have been able to find only one case of solitary bone cyst in the spinous process. All four patients reported in the literature were over 30 years of age. The patient in the current case was a 13-year-old girl with no history of trauma.
Methods: Radiographs and a computed tomography scan of the cervical spine were performed before the operation, as was a histologic examination to make a diagnosis of the lesion.
Results: The intraoperative findings from examination of the stagnant fluid within the lesion and the histologic examination indicated the diagnosis of a solitary bone cyst.
Conclusions: A solitary bone cyst in the spine is rare, especially in the young. An osteolytic lesion in the spinous process of the spine tends to be diagnosed as an osteoblastoma or as a giant cell tumor of the bone. A solitary bone cyst of the spine, although rare, must be considered as a differential diagnosis.