DENVER -- There are a multitude of problems and risks Americans face when they pick up the car keys and drive. Between high gas prices, flat tires and failing engines, cars and the troubles that go along with them can provide a real roadblock. Yet, there is a more serious risk all drivers take when they put their foot on the wheel: whiplash.

According to the Spine Research Institute of San Diego, three million new whiplash injuries occur every year in the United States. Whiplash, also known as Cervical Acceleration Deceleration or (CAD), typically occurs from rear impact collisions, when the bumper is compressed and the vehicle is forced forward. When such collisions occur, the torso is shoved back into the seat, which loads the seatback. As a result, both the neck and head rise upwards, coming in contact with the headrest. Due to the position of the headrest, whiplash can occur.

"Whiplash injuries occur before the head rotates as its moving backward relative to the thorax; the key is the relationship between the head and the chest," Brian Stemper, Ph.D., a biomedical engineer at the Medical College of Wisconsin, said.

Injuries tend to occur in the beginning phases of a car accident, he added, and women are five percent more susceptible to the injury because of the flexibility in their cervical spines.

Whiplash injuries are painful and detrimental not only because they can become chronic problems that last for months or years, but also because most people think the whiplash problems will solve themselves. After people are hurt in rear impact collisions, they often suffer from neck pain, headaches, dizziness, memory problems, unsteadiness, fatigue and lower back pain (Spine Research Institute of San Diego).

Most of the time, symptoms do not show up immediately after the accident, but 24 to 48 hours later. First symptoms of a serious whiplash injury are neck stiffness, muscle spasms and shoulder pain, followed by a reduction in neck range motion.

Because whiplash injuries affect the soft tissues of the cervical spine and cause spinal cord injury, it is important to seek professional treatment and to take the right steps to prevent future whiplash injuries. You cannot prevent other drivers from hitting you, but you may be able to protect your neck with new technology.

Stemper has studied whiplash injuries for over a decade and is taking steps to improve the risks associated with whiplash. He is working with automakers that are developing head restraints to help prevent injuries. Even without the newest equipment, simply taking the time to adjust your headrest can make a big difference in rear end collisions.

"You want to set your head restraints so that it's very close to the back of your head," he explained. "Each time drivers and passengers get in a car, they should be sure the head restraint is correctly positioned to minimize injuries."

Stemper created a mathematical computer model of the head and cervical spine and studied it using simulated rear-end collisions. The computer response was examined in 57 different measures of realistic spinal motion. The model can be used to determine quantifiable data on soft tissue distortions in humans.

As Stemper explained, the model shows that "auto head restraints positioned less than 2.4 inches from the back of the head kept ligament stretch within the physiologic range."

Basically, using these guidelines, many injuries could be prevented. It is when the restraint distance goes beyond 2.4 inches that whiplash occurs. Head rest position is crucial, because when the head rest is too low and far back, injury can easily occur.

By placing the rest level with the top of your head and two inches or less from the back of it, head moment is limited and whiplash prevented. Before you turn on the car and take a drive, remember to check that your seatbelt is on and your headrest adjusted.

Additional Resource:
Medical College of Wisconsin
Toranj Marphetia, Public Relations
(414) 456-4700
tmarphet@mcw.edu
MCW.edu