This paper describes improvements made to the injury risk curves for peak neck tension, peak neck extension moment and a linear combination of tension and extension moment that produce peak stress in the anterior-longitudinal ligament at the head-to-neck junction. Data from previously published experiments - that correlated neck injuries to 10-week-old, anesthetized pigs and neck response measurements of a 3-year-old child dummy that were subjected to similar airbag deployments - are updated and used to generate normal probability curves for the risk of Abbreviated Injury Scale (AIS) equal to or greater than 3 neck injury for the 3-year-old child. These curves are extended to other sizes and ages by normalizing for neck size. Factors for percent of muscle tone and ligamentous failure stress as a function of age are incorporated in the risk analysis. The most sensitive predictor of AIS equal to or greater than 3 neck injury for this data set is peak neck tension. If two possible outliers are deleted from the data set, then the combined criterion of extension moment and axial force becomes the most sensitive predictor which is consistent with expectations. (A)
Abstract