Traumatic Posterior Atlantoaxial Dislocation Without Fracture of Odontoid Process: A Case Report and Systematic Analysis of 19 Cases.

OBJECTIVES: To evaluate the ideal treatment strategy for traumatic posterior atlantoaxial dislocation without fracture of odontoid process.

DESIGN: Case report and systematic analysis based on the methodology of evidence-based medicine.

SETTING: Level IV trauma center.

PATIENTS: Nineteen patients who suffered from traumatic posterior atlantoaxial dislocation without fracture of odontoid process.

INTERVENTION: Closed reduction, open reduction, internal fixation, and fusion.

OUTCOME MEASURES: Neurologic status, range of motion, and radiographs for stability or fusion.

RESULTS: Nineteen cases were included in this analysis. The mean age was 37.7 ± 13.8 years (range, 20-65 years). Sixteen cases (84%) were male, and 3 cases (16%) were female. Thirteen cases (68%) have a transient loss of consciousness. Ten cases (53%) presented no neurologic deficits. All 9 patients (47%) with neurologic deficits recovered without any residual deficits. Eleven dislocations (58%) were reduced by closed reduction, followed by fusion in 5 of them (45%), and the remaining 6 dislocations (55%) were treated conservatively. Eight dislocations (42%) were treated by open reduction and fusion.

CONCLUSIONS: Traumatic posterior atlantoaxial dislocation without fracture of odontoid process usually presents without a severe neurologic deficit. Even if it presents with mild or transient neurologic deficit, it would be restored without any residual deficits. Closed reduction is usually successful and safe. The need for fusion after successful closed reduction depends on the integrity of the transverse ligament and the stability of cervical spine. If anatomic reduction is not achieved by closed reduction, open reduction and fusion should be performed.