Odontoid fractures following blunt trauma

Fractures of the odontoid process typically result from forceful blunt trauma. They often produce instability of the cervical spine, and may be associated with neurologic impairment. This study was designed to examine the epidemiology and demographics of odontoid injuries, including their incidence and prevalence relative to other spine injuries, the prevalence of associated injuries, and the likelihood of neurologic impairment. Of 34,069 enrolled blunt trauma victims, 818 (2.4 %) sustained a cervical spine injury, 94 of whom had a fracture of the odontoid. The relative prevalence of odontoid fractures varied by age, ranging from less than 3 % among individuals under age 20 years, to greater than 20 % in patients over 80 years old. Classification by Anderson–D'Alonzo criteria revealed 6 type I injuries, 60 type II injuries, and 27 type III injuries; one vertical injury could not be categorized. Over half of the odontoid fracture victims sustained additional cervical spine injuries, with 90 % of these injuries involving the atlanto-axial complex. In addition, non-spine-related injuries were found in 52 % of odontoid injury victims, over one-third (34 %) presented with an altered level of alertness, and almost one-quarter (23 %) exhibited some form of focal neurologic deficit associated with their injury. Fractures of the odontoid are among the most frequently encountered cervical spine injuries, and increase in prevalence with increasing patient age. Odontoid fracture victims often have other spine injuries, particularly to the atlanto-axial complex, and may harbor other non-spine-related injuries and neurologic pathology.