Seat belt and airbag expert witnesses at Technology Associates describe “whiplash”:
What is the syndrome called “whiplash”? Here is a brief description. A stopped car is struck by another vehicle from behind; the struck car and torsos of its passengers are thrown forward. However, the heads of the passengers lag behind for a fraction of a second, causing their necks to be hyper-extended (unduly strained as the torso flies forward while the head stays behind). As their torsos rebound against the seat backs, their heads now move forward, but are snapped back again, by their necks, and overshoot the torso, again causing the neck to be hyper-extended. This effect is most severe if the headrests are too low and set too far back, as they are in many cars. The whole occurrence takes less then a second.
Although the person experiencing this situation does not have overt signs of injury, the possible occurrence of soft tissue damage to the overstretched ligaments of the neck has been well documented. This damage may be permanent, causing chronic pain and limitation in neck movement, the full extent of which may not be apparent until about a day after the accident.