<unk> can be described as a sudden strain to the muscles, bones and nerves in the neck. The neck is made up of seven vertebrae, referred to as the cervical vertebrae. The first two cervical vertebrae, the axis and atlas, are shaped differently from the remaining five. The atlas and axis are responsible for movement of the skull from side to side (cervical rotation to the right and left); also moving forward and backward (cervical flexion and extension). Excessive extension and flexion can disrupt the vertebrae. There are four phases that occur during<unk> ": Initial position (before the collision), retraction, extension and rebound. In the initial position there is no force on the neck it is stable due to inertia. Anterior longitudinal ligament injuries in<unk> may lead to cervical instability. They explain that during the retraction phase that is when the actual<unk> " occurs, since there is an unusual loading of soft tissues. The next phase is the extension, the whole neck and head switches to extension, and it is stopped or limited by the head restraint. The rebound phase transpires as result of the phases that are mentioned. During the retraction phase, the spine forms an S-Shaped curve, and this caused by the flexion in the upper planes and hyperextension at the lower planes and this exceed their physiological limits this phase the injuries occur to the lower cervical vertebrae. At the extension phase, all cervical vertebrae and the head are fully extended, but do not surpass their physiological limits. Most of the injuries happen in C-5 and C-6.
Whiplash 
Swayback
Sprain
Post-nasal drip
Tennis injuries
Factitious airs
Laryngospasm
Crossbite