Atlantoaxial rotatory dislocation. A case report.

STUDY
DESIGN: Report of a child who sustained an acute atlantoaxial rotatory dislocation, associated with fractures of the clavicle and the temporal bone, and rupture of the alar ligament demonstrated by magnetic resonance imaging.
OBJECTIVE: To describe the radiographic and pathoanatomic characteristics of the injury process. SUMMARY OF BACKGROUND DATA: Only five cases of traumatic atlantoaxial rotatory dislocation associated with fracture of the clavicle have been reported previously. This is the first report of a ruptured alar ligament demonstrated on magnetic resonance imaging in a patient with atlantoaxial rotatory dislocation associated with fractures of the clavicle and the temporal bone.
METHODS: Computed tomography revealed the Type 1 rotatory dislocation described by Fielding and Hawkins, and magnetic resonance imaging delineated the ruptured alar ligament.
RESULTS: Traction in a halter, followed by 6 weeks of immobilization with a cervical collar, was successful in the management of the injury.
CONCLUSION: Concomitant fractures of the right temporal bone and the right clavicle may yield excessive left rotation of the atlas on the axis, resulting in the rupture of the right alar ligament. Awareness of this condition allows early diagnosis and effective conservative treatment.