RESUMO
Introduction: Os odontoideum is a rare lesion of the axis. Described as an ossicle, consisting of smooth and separate caudal portions of the odontoid process wherein its etiology has remained controversial. Os odontoideum complicating a possible osteogenesis imperfecta has not been reported before in the literature. Methods: We report the case of a 14-yr male patient presented with progressive weakness of both lower and upper extremities after a head trauma 10 months prior to admission, which presented as transient quadreparesis. Results: Magnetic resonance imaging of cervical spine showing cervicomedullary junction compression. Patient underwent surgical intervention and 3 months post operation, patient was reported to have steady gait and muscle grading of 5/5 on all extremities. Conclusion: Surgical fi xation and fusion in patients with instability may prevent catastrophic neurologic insult after minor trauma in the future.