Combined fractures of the odontoid process and upper thoracic spine: two case reports.

We describe two cases of combined fractures of the odontoid process and upper thoracic spine that have not been previously reported. The first patient, a 21-year-old man, sustained an odontoid process fracture with posterior displacement and a fracture-dislocation injury at T4/5 in a motorcycle accident. The second patient, a 66-year-old woman, fell from a cliff and sustained an odontoid process fracture with posterior displacement and a bursting fracture at T3 and T4 with rotation. The first patient exhibited complete paraplegia below the T5 level of the spinal cord. The second patient escaped neurological deficit. Both underwent anterior screw fixation of the odontoid process and posterior fusion of the upper thoracic spine. In both cases the cervical spine seemed to be in hyperextension, and the upper thoracic spine experienced sudden flexion and rotation forces.