How Could I Be Hurt If My Car Isn’t Damaged?
A question most people don’t understand the answer to. The insurance industry would like you to believe that this is true. It is absolutely the opposite of what you might think and simple physics is the answer. Look no further than the sport of auto racing as proof. Ever witness a severe crash on TV when these stock cars are going 200 mph? The reason he is able to walk away IS that the car was demolished in the collision. One of the many safety measures in these automobiles is the energy absorption created when the car crushes. The cockpit, however, remains intact, saving the driver from any crushing. If the car crushing absorbs the energy then the occupant does not. Another example is the perpetual motion toy you might find on an executive’s desk. The marbles are rigid, do not absorb energy and therefore can pendulum back and forth almost perpetually.
Street cars of today have many of the same safety measures that save lives every day in crashes above 35 mph. However, the insurance industry lobbied the government years ago to increase the rigidity of rear bumpers. They did this to reduce damage claims. However, this resulted in an increase in the number of injuries in low speed rear impact collisions. The reason again is simple physics. Isaac Newton’s second law of motion (F = m A) Force equals the mass of an object times the acceleration. Obviously, a vehicle has a large mass so it does not take much acceleration to create a significant force. The facts are you can be injured in a 5 mph crash.
If a car does not crush during impact, 100% of the force at impact is transferred into the occupant. In fact, even more energy is transferred into the occupant because of the springs and cushions in the seat back. These create a slingshot effect on the occupant. As the car moves out from under the occupant in a rear impact collision, the occupant sinks back into the seat. Eventually, the occupant changes direction and is launched forward. At the same time, the seat belt and shoulder harness cinches down on the occupant in the opposite direction resulting in the whiplash effect.
There are many risk factors that increase the likelihood for injury. Some of the more significant ones are discussed below. Rear impact collisions are the most likely type of collision to be injured in. Females are 50% more likely to be injured in car crashes than males. This is because of a man’s increase in muscularity and ability to resist the impact, generally speaking. Smaller females are at even greater risk. Lack of awareness of the impending collision may be the most significant risk factor. If you see it coming, you have time to react and tense your muscles which prevents excessive motion. This can reduce the injury to the ligaments in the neck and spine as well as reduce compressive forces on the spine which often result in disc injuries.
Other significant risk factors for injury include but are not limited to: Having your head or body turned at impact. Poor head restraint geometry (tall occupants having the headrest pushed all the way down), wearing the shoulder harness and non-failure of the seat back. This is not to suggest that you not wear your seat belt as it has been proven that a seat belt can save your life. However, the seat belt can be a factor in the likelihood of injury.
In Summary, do not judge the likelihood of you or someone you know being injured in a car crash based on the damage to the vehicle. The opposite is in fact true and supported by the physics as well as the literature. Consider this if you or a loved one are ever involved in a crash with little or no damage. Don’t assume everyone is uninjured. Some injuries after a crash take time to develop. Much like when you exercise when you haven’t in a while. You may not be sore right away. But you get REALLY sore 2 or 3 days later. Be certain to see a chiropractor experienced in these types of injuries for a thorough evaluation and don’t sign anything releasing the other party from responsibility for at least 30 days.
Dr. Steven S. Smith D.C. – Dr. Smith holds an Advanced Certification in Whiplash Traumatology and Biomechanics from The Spine Research Institute of San Diego. He has been in practice since 1994 and treated thousands of car crash injuries.