Dysraphic lesions of the cervical spinal cord.

Cervical spina bifida, either occult or overt, is relatively uncommon. These lesions tend to be associated with other abnormalities of the central nervous system and spine. For the occult dysraphic lesions, a Klippel-Feil syndrome is a particular association, especially the type I variety. For the spina bifida cystica lesions, the more common associated features include a Chiari II malformation and hydrocephalus. Spina bifida cystica in the cervical region is different from the myelomeningocele of the lower spine and is characterized by two types of abnormalities: the myelocystocele herniating posteriorly into a meningocele and a meningocele with or without an underlying split cord malformation. In both the occult dysraphic states and spina bifida cystica, there is underlying tethering of the cervical spinal cord, which can cause late neurologic deterioration, and surgical treatment is indicated both for cosmetic reasons and to untether the spinal cord. Children with spina bifida cystica may have neurologic dysfunction that may not be evident at birth or in the first few months of life but may be identifiable as the child grows older. One needs to be cautious about providing too optimistic a prognosis with respect to neurologic dysfunction based on a neonatal examination and to recognize that the appearance of neurologic deficits may not indicate deterioration.