[Four cases of hangman's fracture].

Four cases of hangman's fracture were reported. The cases were disturbed between 67 and 85 years of age and all were males. The exact mechanisms of injuries of these cases were not precisely documented, but all struck the head by falling for some distance. Three of them showed cerebral concussion immediately after injuries. One of four patients had complete transverse cord lesion at C5 level and the other showed right Brown-Séquard syndrome at C4 level, while another two showed no neurological deficits except for neck pain. Radiological findings disclosed fracture of the pedicles or the lamina of the axis and anterior spondylolisthesis of the axis upon the third cervical vertebra. In one patient, fracture of the body of third cervical vertebra was combined. All cases were initially treated by skeletal traction, in order for reduction of dislocation, then fixation of the injured spine. Steroid and mannitol were administered to patients with complete cord section and Brown-Séquard type of lesion. Two out of four patients showed uneventful clinical course. A patient shown Brown-Séquard syndrome revealed fairly good recovery, and another with showing transverse cord lesion died from fatal gastrointestinal bleeding 15 days after injury. Analysis of C2 fractures experienced in these four cases suggested that direct downward forces along the longitudinal axis when the head remained in extension or flexion caused these fractures, whereas pure hyperextension injures of the upper cervical spine, which has been considered as main mechanism, had only a minor role.