Accidental decapitation: an unusual injury to a passenger in a vehicle.

A case of decapitation of a vehicle passenger in an accident on a highway is reported. Evaluation of roadside evidence and the deceased's injuries revealed that the victim was partially ejected from a broken passenger-side window as the vehicle spun out of control, decapitation being due to the impact of his head against a barrier stanchion on the shoulder of the road. An unfastened seat-belt, high-speed driving and the construction of the road barrier were contributory factors.