Atlanto-axial Dislocation Simulating a Head Injury; Hypoplasia of the Odontoid

D.H.., a 14-year-old girl, was entirely well until May 9, 1965. On entering an automobile she had grazed her forehead on the inner roof of the car. She then fell backward so that the back of her head struck the pavement. Observers stated she was semi-responsive and appeared to be struggling to say she could not breathe. Her friends urged her to get up and go home, but she rapidly became unresponsive. She was rushed to a local hospital where she was found to be cyanotic, completely areflcxic, and was believed to be moribund. Since a surgeon was not available, immediate transfer to the University of Michigan Hospital was arranged. Ill the ambulance, the patient was given intravenous 50 per cent glucose to reduce presumed cerebral swelling and her head was kept in extension to provide an airway. Examination in the emergency room revealed a cyanotic, comatose, slender female who responded only to severe stimuli and then only by moving the right arm and leg. The blood pressure was 90/60 and the pulse was 110 and weak. Respirations were ~4 per minute, irregular and labored. In addition to the apparent left hemiplegia, a left Babinski was present and both arms arid legs were hypotonic and hyporeflexic. Pupils were dilated to mid-range and reacted only sluggishly to light. Corneal reflexes were depressed but there was no evidence of facial paresis and a gag reflex was present. There was no external evidence of trauma to the head. Respiration was marked by flaring of the nostrils and the use of accessory muscles. Intercostal function was decreased bilaterally. Breath sounds were reduced over the left side of the chest. The abdominal musculature appeared flaccid and diaphragmatic motion was paradoxical. These findings could not be explained by a head injury alone. Skull and chest films were normal. Cervical spine films in a neutral position appeared normal, but with the head held in extension, there was obvious dislocation of the atlas posteriorly on the axis (Fig. 1). Skeletal traction by means of Vinke tongs was immediately instituted. The patient was placed on a Stryker frame and given oxygen. Several hours later, she had improved to the point where she was awake, and able to converse,