Acquired spinal cord lesion associated with os odontoideum causing deterioration in dystonic cerebral palsy: case report and review of the literature.

A boy with a dystonic quadriparesis presented with acquired paralysis, spasticity, and a feeding disorder. Spinal MRI revealed a cervical cord lesion and os odontoideum. Excessive movement of the neck, leading to failure of ossification of the dens and then to cervical cord trauma was the likely mechanism. The poor outcome of this subject is described, emphasising the need to pay careful attention to neurological changes in children with extrapyramidal cerebral palsy, who may be at particular risk of cord pathology. The management issues are discussed.