Report investigating the importance of head restraint positioning in reducing neck injury in rear impact.

Neck injury resulting from rear impact (often known as whiplash) is a serious cause of road trauma. It is often underestimated or overlooked because such injuries are minor on traditional injury scales but can result in long term pain and disability. The paper begins with a brief review of research into head restraints and whiplash done so far. A review of international head restraint regulations revealed the absence of any horizontal offset requirements. A review of seat strength requirements and testing procedures showed that a regulation that required a collapsible seat would involve significant compliance testing. This paper concludes a preliminary project conducted by the Federal Office of Road Safety (FORS) where the head restraints for twenty Australian market vehicles were assessed using known performance criteria. A key finding of the report was that most of the vehicles allowed for vertical adjustment of the head restraint. Also important was that none of the vehicles measured allowed horizontal adjustment and on some of the head restraints the horizontal displacement increased as the vertical height increased. As the understanding of neck injury mechanisms in rear impact develops, there may be some scope for FORS to facilitate the improvement of these standards. Further research into neck injury mechanisms may reveal yielding seat backs or new 'active' head restraint technology as a more effective countermeasure. In the meantime, educating occupants to correctly adjust their head restraints seems to be an effective way to reduce injuries in existing vehicles.