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The Four Phases of a Whiplash Injury

In an automobile collison, your body goes through an extremely rapid and very intense hyper-flexion and hyper-extension of the spine. This causes four phases of "whiplash" to the body movements that contribute to the overall injury; and, with such a sudden and forcefull movement, damage to the vertebrae, nerves, disc, muscles, and ligaments of your neck and spine can be substantial.

Phase 1

During this first phase of the impact, your car is pushed out from under you, causing the mid-back to be flattened against the back portion of your seat. This results is an upward force in your cervical spine, compressing your spinal discs and joints. As your seat back begins to accelerate your torso forward, your head moves backward, creating a shearing force in your neck. If your head restraint is properly adjusted, the distance your head travels backward will be limited. However, most of the damage to the spine will occur before your head even reaches the head restraint. Studies have shown that head restraints only reduces the risk of injury by 11-20%.

Phase 2

With phase two, the torso has reached peak acceleration (1.5 to 2 times more than your vehicle) but your head has not yet begun to acceletate forward and continues to move backward. An abnormal S-curve often develops in your cervial spine as the back of your seat recoils forward, much like a springboard, adding to the forward acceleration of the torso. Unfortunately, this forward "seat back recoil" occurs while your head is still moving backward, resulting in a shearing force in the tissues of the neck and is one of the more damaging aspects of a whiplash injury. Most injuries occur during this action. The S-curve if commonly seen on X-ray of the neck following a motor vehicle collision.

Phase 3

In the third phase, while the car is slowing down your torso (within a fraction of a second) is now descending back down into the seat while your head and neck are actually at their peak forward acceleration. If you unknowingly release the pressure on the brake pedal during the first phases of the collision, it will likely be quicker and increase the severity of the flexion injury to your neck.

Phase 4

This results in a violent forward-bending motion of the neck, straining the muscles and ligaments, tearing fibers within the spinal disc, and forcing vertebrae out of their normal position. Your spinal cord and nerve roots will get stretched and irritated, and your brain can even strike the inside of your skull causing mild or moderate brain injury. If you are not properly restrained by the seat belt or shoulder harness, you may suffer a concussion, or even a severe brain injury, from striking the steering wheel, dash or windshield.

Summary of Whiplash Trauma

As with the discussion above, whiplash injuries can mainfest in a wide variety of ways, including neck pain, headaces, cognitive changes, fatigue, upper back / shoulder / arm pain, and even low back pain with leg radiations. Due to the fact that numerous factors play into the overall whiplash trauma, such as direction of impact, speed of the vehicles involved, as well as age and physical condition, it is impossible to predict the pattern of symptoms that each individual will suffer. There are, in fact, a number of conditions that are very common among those who've suffered from whiplash trauma. Don't take them lightly... get checked today.

We hope you enjoy the information within and share it with others. Again, thank you for visiting and remember to come back often.

Yours in health,

Dr. David A. Spring