The incidence of neck injury from motor vehicle accidents is quite low in children. Serious neck injury in forward-facing restrained children is quite rare, and has been reported in moderately severe collisions in North America and Europe, where four- and five-point child restraints are used without a top tether. No case of serious neck injury has yet been reported in correctly restrained children in Australia, where six-point harness restraints are used with a top tether. The Vehicle and Equipment Safety Division of the Roads and Traffic and Authority (RTA) in New South Wales, Australia recently began a test programme, which was designed to quantify several parameters, including the effects of top tether anchorage and the actual geometry of the anchorage on neck loads produced in child dummies in simulated collisions. The programme's first stage has already tested some restraints and anchorage configurations in simulated frontal impacts, with a velocity change of 49kph and a peak deceleration of 26g. The dummy used was a fully instrumented six-month CRABI. The usage and geometry of a top tether seems to affect neck loads; for example, high mounted tethers seem to reduce the axial loads placed on a child dummy's neck in frontal impact. These preliminary results suggest that a child's neck is more vulnerable to axial loads.
Abstract