Basilar impression in children.

Ataxia is a common neurologic sign in childhood. Basilar impression due to bony abnormalities of the craniovertebral junction is an uncommon but readily treatable cause of ataxia in children. Two children who had neck stiffness, ataxia, nystagmus, and corticospinal tract signs are described. Basilar impression was recognized only after specific radiologic studies were performed. Both children were treated surgically with good results.