Whiplash in Low Speed Vehicle Collisions
“…experimental results indicate that some vehicles can withstand a reasonable high speed impact without significant structural damage [crush]. The resulting occupant motions are marked by a lag interval, followed by a potentially dangerous acceleration up to speeds greater that of the vehicle.
As the vehicle becomes stiffer [less crush], the vehicle damage costs are reduced as less permanent deformation takes place. However, the occupant experiences a more violent ride which increases the potential for injury.
…the average acceleration experienced by the occupant in the elastic [no crush] vehicle would be approximately twice that of the plastic [crushed] vehicle. This theory implies that vehicles which do not sustain damage [crush] in low speed impacts can produce correspondingly higher dynamic loadings on their occupants than those which plastically deform under the same of more severe impact conditions.”
• In 1993, the journal Trial Talk published a study titled (20):
The Physics, Biomechanics and Statistics of Automobile Rear Impact Collisions
“The absence or presence of vehicle damage is not a reliable indicator of injury potential in rear impacts. Based upon the principle of conservation of energy, any energy which does not go into damaging [crushing] the vehicle must be converted into kinetic energy, the source of injuries.”
• In 1997, the journal of the Society of Automotive Engineers published a study titled (21):
Lack of Relationship Between Vehicle Damage and Occupant Injury
Using a mathematical analysis and examples from a pole vaulter and high performance racing car crashes, this article explains vehicle crush actually reduces injury to occupants. The author notes that racing cars are designed with state-of-the-art crash engineering. When racing cars are in a collision, they appear to almost shed their body structure and crush in almost every direction. This design is to dissipate energy in a collision and reduce injurious peak G forces to the occupant. The results are very low driver injury rates, even though the collisions involve very high speeds.
“… the body of the racing car is sacrificed to prevent driver injury or death.”
• In 2005, the Journal of Neurology, Neurosurgery, and Psychiatry published a study titled (22):
Whiplash Following Rear-end Collisions: A Prospective Cohort Study
“It is surprising that it has not been possible to relate estimated striking speeds to early whiplash or to any measure of neck pain severity either early on or at 1 year.”
In this study, driving a large car and being struck increased the risk of neck pain. This “seems counterintuitive.” “Large cars are less likely to deform [crush] and therefore more of the energy of the collision was transmitted to the occupants.”