Rear impact neck protection by reducing occupant forward acceleration:​ a study of cars on Swedish roads equipped with crash recorders and a new anti-whiplash device

Krafft, Maria<sup>1,2</sup>; Kullgren, Anders<sup>1,2</sup>; Ydenius, Anders<sup>1,2</sup>; Boström, Ola<sup>3</sup>; Håland, Yngve<sup>3,4</sup>; Tingvall, Claes<sup>5</sup>

By changing the seat force-deflection characteristics in an older car model without a certain whiplash-protection system, an after market Anti-Whiplash Device (AWD) was evaluated. The AWD is mounted under the front end of the seat-rails. In a rear impact, the forward acceleration of the occupant is reduced by a force controlled yielding of the seat front attachments. The aim was to evaluate the injury reducing effect of a principal system by studies of real-life accidents and crash tests. Approximately 8,000 cars were fitted with the AWD to the driver’s seat and approximately 12,000 of the same car model formed a control group. All cars were equipped with a crash recorder, which measures the acceleration time history at the moment of impact. The risk of persisting symptoms (> 6 months) was significantly lower for drivers in cars fitted with AWD than without. The crash tests show that the risk is more than halved with the AWD than without.

Keywords: whiplash; rear impacts; long-term consequences

Year

Entry

2001

Viano DC, Olsen S. The effectiveness of active head restraint in preventing whiplash. J Trauma. November 2001;51(5):959-969.

1990

Olsson I, Bunketorp O, Carlsson G, Gustafsson C, Planath I, Norin H, Ysander L. An in-depth study of neck injuries in rear end collisions. In: Proceedings of the 1990 International IRCOBI Conference on the Biomechanics of Impact. September 12-14, 1990; Lyon, France.269-278.

2003

Eriksson L, Kullgren A. Influence of seat geometry and seating posture on NIC_max and N_km AIS 1 neck injury predictability. In: Proceedings of the 2003 International IRCOBI Conference on the Biomechanics of Impact. September 25, 2003; Lisbon, Portugal.217-231.

1997

Boström O, Krafft M, Aldman B, Eichberger A, Fredriksson R, Håland Y, Lövsund P, Steffan H, Svensson M, Tingvall C. Prediction of neck injuries in rear impacts based on accident data and simulations. In: Proceedings of the 1997 International IRCOBI Conference on the Biomechanics of Impact. September 24-26, 1997; Hannover, Germany.251-264.

1995