Congenital anomaly of the second cervical vertebra predisposing to progressive cervical myelopathy. A case report.

The authors describe a previously unreported constellation of developmental anomalies of the C2 vertebra, which predisposed to the development of cervical myelopathy in a young patient. The embryology of the vertebral column is reviewed briefly, and the origin of each anomaly of the C2 vertebra is traced to one of the two early stages in development as follows: 1) the formation of the mesenchymal vertebra or 2) its induction to cartilage. This case emphasizes the importance of congenital stenosis in the development of cervical myelopathy in young patients. The outcome is favorable when it is treated aggressively.