Fatal injuries of the brain stem and/or upper cervical spinal cord in traffic accidents: nine autopsy cases.

Nine forensic autopsy cases were studied. All had injuries of the brain stem and/or upper cervical spinal cord due to traffic accidents. Among the nine subjects, eight were pedestrians and one was a left, front seat occupant of a vehicle. Examination of these 9 cases revealed that three had ponto-medullary avulsion, two had medullary avulsion and the other four had laceration of the upper cervical spinal cord. Atlanto-occipital dislocation was observed in five cases, and a ring fracture around the foramen magnum in the other two cases. Intraventricular haemorrhage, probably due to tears of the choroid plexus caused by hyperextension or hyperflexion of the head, was found in seven cases. In just one of these seven cases, both of the lateral ventricles were filled with dark red haemocoagulum. Hyperextension is considered to occur more commonly in road trauma cases where the victim is alcoholically intoxicated.