Whiplash occurs when the neck is suddenly and forcibly bent backward and forward. This causes injury to the joints of the neck, known as the cervical vertebrae, and to the surrounding soft tissue. The most common causes of whiplash are motor vehicle accidents, especially when the vehicle is struck from the rear.
Whiplash injuries usually happen to a person who is not wearing a seat belt when a motor vehicle is rear-ended. As a result of whiplash, the ligaments in the neck may be stretched or even torn. Sometimes fractures in the vertebrae may also be involved.