In October 1999, a twenty-two-year-old man injured in a motorcycle accident was seen at the Heinrich-Braun Hospital in Zwickau, Germany. He could not provide details of the accident, as he was unconscious for a few minutes immediately after it occurred. In the emergency room, the patient was alert and oriented. He had a blood pressure of 140/70 mm Hg and a pulse of ninety-two beats per minute. Examination revealed extensive lacerations to the throat, chin, mouth, and lips. The patient reported pain and tenderness in the neck, and the left forearm was swollen. There were no evident chest or abdominal injuries. Neurologic examination demonstrated no apparent deficit of the spinal cord or cranial nerves.
Because the patient was reported to have been unconscious at the scene of the accident, an initial computed tomography scan of the head was performed. It showed multiple facial fractures, including a maxillary fracture, a fracture of the left mandibular angle, and fractures of the alveolar processes with dislocation of three teeth. A computed tomography scan of the cervical spine demonstrated a posterior atlantoaxial dislocation without a fracture of the odontoid process (
Fig. 1 ). Radiographs of the left upper extremity revealed fractures of both forearm bones.
The patient was taken emergently to the operating room and, after fiberoptic intubation, underwent a manual closed reduction of the atlantoaxial dislocation. Spinal cord monitoring was not available. The reduction maneuver, performed with use of a halo ring, involved distraction, hyperextension, and slight lateral bending of the neck under fluoroscopic control. Two attempts at closed manipulation were necessary to reduce the dislocation. When the patient was awakened from the anesthesia he was neurologically intact. Controlled active flexion and extension of the cervical spine under fluoroscopic control in the operating room showed no instability. A computed tomography scan performed two hours after the reduction demonstrated anatomic reduction (
Fig. 2 ). The patient wore a halo vest for three months. After it was removed, active flexion-extension radiographs and a computed tomography scan confirmed anatomic reduction with no residual instability.
Two years after the accident, the patient was free of pain and had lost only 30° of cervical spine rotation. He was employed as a driver and had no restrictions of his daily activities. Flexion-extension radiographs and a computed tomography scan of the cervical spine showed no instability and only minor reactive changes in the atlantoaxial joint (
Fig. 3 ,
4-A, and 4-B ).