Sitting Position Can Influence Risk of Whiplash

Photo: Woman who drives a car

Women are more affected by
whiplash injury in car crashes;

This has been shown by a dissertation of Bertil Jonsson at Umeå University in Sweden. Neck injuries among vehicle drivers as a result of being rear-ended remain a major problem for victims and cost insurance companies and society huge sums.

The dissertation elucidates differences in the sitting position between women and men in the various seats of a car that can provide a partial explanation of the risk differentials observed. Women drivers adjust the driver seat differently than male drivers do: women sit higher and closer to the steering wheel and have the seat back more upright.

Men have a greater distance between the back of their head and the neck support (backset) compared with women, both when the car is stationary and when driving. If the driver holds his/her hands on the upper part of the steering wheel, the backset distance also increases to the head support compared with the passenger position. High backset values are a known risk factor for neck injuries in rear-end collisions.

The scope of the neck to move in a horizontal backward direction (retraction) is different between the sexes, but it is also affected by sitting position. A slouched posture entails a greater distance to the head support and also reduces the scope for free movement backward (retraction). When this scope is exceeded, injuries probably occur.

Current crash dummies used to develop vehicle seats and neck supports, for instance, are geared to men of normal size, but not to women. This is especially true in regard to height. Nor does testing methodology take into consideration differences between the sexes, or differences in sitting position between the driver’s seat and the front passenger seat. The findings provide a foundation for the development of new test methods and protective systems in future vehicles that could reduce the risk of neck injury in rear-end collisions.; Source: Swedish Research Council