Traumatic occipitoatlantal dislocations.

Fourteen occipitoatlantal dislocations were treated during an 11-year period. All patients presented with neurological deficits and definite evidence of spinal instability. Plain radiographs provided the diagnosis conclusively in 11 patients. Three patients required computed tomography (CT) or magnetic resonance (MR) imaging for diagnosis. Rotational subluxations were radiographically occult and associated with less severe neurological injuries compared to distracted or translated subluxations. Ten patients died acutely. One patient, who had complete C1 level quadriplegia, died after 3 months. Three patients with incomplete spinal cord syndromes had long-term survival and functional neurological recoveries. Extensive ligamentous injury predisposed patients to recurrent subluxations. In several patients, traction or a cervical collar caused distraction and neurological injury. Halo immobilization and urgent fusion are necessary for patients with salvageable neurological function. Nonoperative measures are inadequate for immediate or long-term spinal stability.