In frontal impact, thorax and head injuries have strongly decreased with the development of occupant restraining systems including airbags, belt load limiters, and pretensioning systems. Nevertheless, the protection of abdomen and lower limbs has still to be improved, especially in rear seats. Indeed, car stiffness has increased in order to keep enough survival space for severe crashes. Thus, car manufacturers have developed specific restraint devices to improve protection of pelvis and lumbar spine, with prevention of submarining. One of these consists of an anti-sliding system based on an inflatable metallic wrap.

The main goal of the study was to investigate the risk of injury with a prototype of such a device, in case of static deployment, for in-position and out-of-position situations. Because the lack of relevance of the dummies in such conditions is suspected, and because criteria do not currently exist as far as the lumbar spine is concerned, six cadaver tests, including three in out-of-position situation, were carried out and duplicated with small female, and 50th male HIII dummies. Two inflators were used.

Cadavers were instrumented with linear accelerometers and angular velocity sensors for vertebra L2, L3, L5 and sacrum. The seat was equipped with load cells.

For the six cadaver tests, no injury was observed. Intervertebral rotation values are given for the cadavers and lumbar spine forces and moments recorded on dummies are presented. Comparisons regarding lumbar spine kinematics are realized for biofidelity assessment.