PROTECTION FOR THORAX INJURY SEVERITY IN 90-DEGREES LATERAL COLLISION

The thoracic trauma index (TTI) and the viscous criterion (VC) are inj ury criteria intended for the prediction of torso injury severity. The criteria were assessed in two series of experiments: 90 degrees (late ral) car to car collisions and controlled left trunk impacts against e ither a rigid or padded wall. Forty-two belt restrained human cadavers in the age range 18-65 years, located in the near-side front passenge r seat, were used. The impact velocity was between 40 and 60 km/h. Lef t and right side impacts were simulated using standard or modified car side structures. With the second series of experiments, the left side of each subject was impacted under one of two different test conditio ns: 24 km/h rigid wall or 32 km/h padded wall. The thorax deformation was Evaluated through the double integration of the accelerated differ ence at the fourth and eight ribs, near and far side, Deformation maxi ma of 6-138 mm (mean 69 mm), VC values of 0.3-4.7 m/s (mean 1.6 m/s), and TTI values of 85-252 (mean 63) occur-red. Torso abbreviated injury severity (AIS) values were between 0 and 5. Statistical analyses show ed a stronger influence of age on injury severity than the injury crit eria or biomechanical responses in the two series of experiments. The TTI showed the highest con-elation with thoracic AIS and the number of rib fractures, while VC was the better predictor of abdominal AIS. Th e results are discussed critically and the strength and robustness of the injury criteria analyzed. (C) 1996 John Wiley & Sons, Inc.