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The Four Phases of Whiplash

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Whiplash is not confined to the world of rear-ended automobiles but can occur in a fall or while playing sport, for example. However, we’ll look here at what typically takes place in an automobile collision – the most common cause of whiplash injury.

As a vehicle hits the rear of your car, your body goes through an extremely quick and violent acceleration and deceleration, and all four of the phases described below happen in less than half a second. Each phase involves a different force acting upon your body that then contributes to the overall injury, bringing vertebrae, nerves, discs, muscles, and ligaments into the equation.

Phase 1– Your car is shunted at great speed from underneath you. Your mid-back is flattened against the back of the seat, creating an upward force in your cervical spine (neck) which compresses your discs and joints. As your momentum continues forward with the car, your head flies backward, and this whips violently at your neck. Only a well-adjusted head restraint can help minimize the damage this causes, lessening the backward travel of your head. However, the majority of damage to the spine will already have occurred before your head hits the restraint, and studies reveal that head restraints only reduce injury by 11% to 20%.

Phase 2– Your torso reaches its peak acceleration of up to twice as fast as the vehicle, but your head is still moving backwards. Your cervical spine is forced into an abnormal S-curve as your seat back springs forward, increasing the speed of your torso even further. The forward seat and backward head then meet in one of the most damaging moments of a whiplash sequence, in which the neck bears the brunt. A lot of the main damage to bone, joint, nerve, and disc happen at this moment.

Phase 3 – Your torso is now settling back down in your seat, and your head and neck are both accelerating forward at their peak speed. This happens as the car is slowing anyway, but this deceleration is aided by your foot planting itself firmly on the brake pedal after possibly lifting off at the moment of impact. This sudden braking severely increases the flexion injury of your neck. Assuming a seat belt is being worn, it now takes the strain of your forward movement.

Phase 4– The most damaging part of the whiplash sequence now occurs. The seat belt stops your torso but your head continues forward. The neck bends violently with the force, straining muscles and ligaments, tearing fibers in the spinal discs, and forcing vertebrae out of position. Your spinal cord and nerve roots are stretched and damaged, and your brain hits your skull, potentially causing mild to moderate brain injury. Where a seat belt has not been used, your head is free to move forward and strike the steering wheel, dash or windshield, causing even more severe brain injuries.

Been in a car wreck? Call Renew Chiropractic in Lakewood. 720-493-5885.

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