Pontomedullary tears and other gross brainstem injuries after vehicular accidents.

In a series of 988 autopsied victims of road crashes, there were 36 (3.6%) cases of gross primary brainstem injury. In this series, the proportion of motorcyclists (41.7%) was double the expected figure. The use of a helmet modifies the mechanisms of impact head injury; the overall benefits of helmet use are well established, but there is need for more research on helmet design.