Answer:
Because in the event of a rear collision, the cervical spine, in the neck region, can project quickly forward and then backwards, causing serious problems if the headrest is not adjusted.
Explanation:
Head support is not widely remembered when talking about driving safety, but its use can prevent serious injuries in the event of an accident. The correct use of the headrest is as important as the seat belt and its usefulness is even greater in cases of rear impact. In rear collisions, it is common to report the whip effect on passengers of the vehicle that was hit. It gets its name because the impact of one vehicle on the rear of another projects the occupants of the car ahead ahead. With the crash, the seat belt holds people's bodies - but not the neck and head. With this, the cervical spine, in the neck region, can quickly project forward and, soon after, backward. Sort of like a rubber band or whip - hence the name.
One of the ways to prevent cervical spine injuries is to adjust the seat headrest correctly. By correctly adjusting the device, in the event of a rear collision, the backrest prevents excessive movement of the neck and head.