The objective of this study is to describe the kinematic response of the head-neck system during low severity rear end impacts. In addition, the effect of anthropometric parameters such as height, weight and neck circumference was investigated. For this purpose, a total of 43 tests with 19 subjects was performed. Values for delta v (velocity change) ranged between 6.5 and 9.5 km/h. Linear accelerations of the head center of gravity (CG) and the first thoracic vertebra (T1) and angular accelerations of the head were obtained. Head angle and head-CG trajectories were obtained from film targets. Finally, head restraint impact forces were measured using a strain gauge attached to the support rods of the head restraint. Although only three females participated in the study, a marked increase in head x-acceleration was observed for the females compared to the males. Neck circumference correlated well with peak head x-accelerations: a thinner neck resulted in higher values for the x-accelerations. The results of the study can be used for evaluation of biofidelity of crash dummy necks, and for validation of mathematical head-neck models. Also, the finding that thinner necks result in higher head peak accelerations may be a partial answer to the question why women are at higher risk for whiplash injuries compared to men.
Abstract