Sleep attacks--apparent relationship to atlantoaxial dislocation.

Sleep attacks, while being characteristic of narcolepsy, have been reported in several metabolic and central nervous system disorders--most of which are refractory to treatment. We have recently treated a 47-year-old man with disabling sleep attacks who was found to have atlantoaxial dislocation. Despite narrowing of the sagittal cervical canal diameter to 12 mm (behind the dens), symptoms of spinal cord compression were mild and intermittent, while signs were absent. Posterior fusion of the C-1 and C-2 vertebrae resulted in relief of symptoms. We suggest that this sleep disorder was a function of impaired efferent control of respiration.