Chiropractic: Physicians Plus

80 Sumner Avenue · Springfield, MA 01108 · Phone: (413) 732-4800 · Fax: (413) 739-4239

CONDITIONS AND CONCERNS

Whiplash

Mechanics of...

Whiplash is most commonly received from being struck from behind, whether from something as light as a fender bender or from something as powerful as a football tackle. When the head is suddenly jerked back and forth beyond its normal limits, the muscles and ligaments supporting the spine can be over-stretched or torn.

In a rear end collision for example, whiplash can be divided into four basic phases:

Phase 1

During Phase 1 the car is first pushed or accelerated forward within milliseconds. Your car is essentially pushed out from under you and your back loads the seat. High shearing forces develop within the neck and your spinal curves straighten and compress. High pressures develops within the brain and shearing forces on the brain stem.

Phase 2

Upward rise of your neck as your head snaps into full extension over the headrest and collapses it. This acts as a fulcrum and TMJ injury is possible with high compression within the joint and some of the muscles and ligaments are stretched or torn in the neck.

Phase 3

The head begins its forward motion as the torso descends into the seat. Seat back bounce increases your velocity 30-70% greater than that of your car. Slack in the seatbelt shoulder harness begins to tighten. Your neck muscles, in a reflex action, contract to bring the the head forward as they are thought to be in extension (phase 2), in an attempt to prevent excessive injury. But, because the head is already traveling in a forward direction as the car decelerates, there is an overcompensation.

Phase 4

This violently rocks the head forward, overstretching more muscles and ligaments in the back of the neck. Full deceleration of the head, neck and torso is aggravated by the shoulder harness. High tension and shear forces in the spine can cause the soft pulpy discs between the vertebrae to bulge, tear, or rupture. Vertebrae can be forced out of their normal position, reducing range of motion (Vertebral Subluxation.) The brain stem, spinal cord and nerve roots get stretched, irritated, and choked. If the victim is not properly restrained the occupant's head may strike the steering wheel or windshield, causing a concussion.

See a sample video.