Bilateral vertebral artery occlusion secondary to atlantoaxial dislocation with os odontoideum: implication for prophylactic cervical stabilization by fusion--case report.

A 27-year-old male presented with an unusual atlantoaxial dislocation associated with os odontoideum, after suffering sudden onset of significant neurological deterioration. Angiography demonstrated simultaneous occlusion of the bilateral vertebral arteries assumed responsible for the devastating neurological deficits. He initially underwent cervical immobilization with a Crutchfield tong for 2 months and subsequent posterior fusion using an iliac bone graft and wires. The neurological symptoms gradually subsided, and 5 years later good healing of the bone graft without instability and ample subarachnoid space around the spinal cord were radiologically confirmed. Early prophylactic stabilization of atlantoaxial dislocation due to os odontoideum is recommended to prevent a poor outcome. Careful angiographic evaluation of the vertebrobasilar circulation is important for management of patients with os odontoideum.