The same group of researchers from the above-mentioned study performed this study. In this paper, however, the authors examined the structure of the vertebral artery (VA) during acceleration. Seven cadaver spines were used in this study, and a "thin nylon-coated flexible cable" replaced the vertebral artery. The researchers subjected the spines to whiplash-type accelerations, and measured the elongation of the cable with each impact.

"The maximum VA elongation during the whiplash trauma significantly correlated with the horizontal acceleration of the sled. The VA exceeded its physiological range by 1.0, 3.1, 8.9, and 9.0 mm in the 2.5, 4.5, 6.5, and 8.5-g trauma classes, respectively."

Previous studies have discussed the occurrence of VA injury from whiplash-related motions. This is the first study, however, to show that the vertebral artery experiences elongation during impact.

Nibu K, Cholewicki J, Panjabi MM, Babat LB, et al. Dynamic elongation of the vertebral artery during an in vitro whiplash simulation. European Spine Journal 1997;6(4):286-289.