A 33- year-old man was a victim of a high speed road traffic accident and he presented a traumatic upper cervical spinal cord injury. He was immobilized in a cervical collar, with tetraplegia and ventilatory assistance. Cervical CT scan showed an unstable dens fracture and distraction between the C1 and C2. Severe distractive hyperflexion or hyperextension accompanied by concurrent axial compression, which may be accompanied by associated rotation, appear to represent the injury mechanism. Dislocation of the cranio-cervical junction and atlanto-axial distraction are very serious injuries. The patient had an unfavorable evolution with death.