Lower back and neck strain injuries: the relative roles of seat adjustment and vehicle/seat design

The incidence of "whiplash" injuries is rising despite the almost universal introduction of head restraints in cars. The incidence of lower back strains is also significant. This paper describes a study of road accident victims suffering from lower back and neck strain injuries. Injury severity was assessed by a disability scoring system, and patients' progress was followed for 12 months. Vehicles were examined to assess impact speeds and seat characteristics. Where possible, measurements were carried out with victims sitting in their vehicles. No differences in victims' symptoms were found between rear as opposed to frontal impacts. Women suffered significantly greater disability than men, despite ostensibly more favourable head restraint positioning. For long-term outcome, smaller horizontal distance from head to restraint was significantly associated with higher disability, contrary to expectations. Seat back inclination was important in lumbar strain cases. There was no clear dependence of injury severity on head restraint vertical positioning, impact direction or impact speed. The possible implications of these results, and possible future strategies for reducing the incidence and severity of neck and lower back strain injuries are discussed. (A) For the covering abstract see IRRD E102514.