Unsuspected atlas fracture and instability associated with oropharyngeal injury: case report.

A case of oropharyngeal injury associated with an unsuspected direct atlas anterior arch fracture is presented. Instability at the occipito-atlanto-axial joints developed because of the coexistence of a rather common congenital defect of the posterior atlas arch. Awareness of the frequency of congenital atlas anomalies and the possibility of direct cervical spine injury with pharyngeal trauma will aid early recognition of this problem and allow early effective treatment.