Cause
The exact injury mechanism that causes whiplash injuries is unknown. A whiplash injury may be the result of impulsive stretching of the spine, mainly the ligament: anterior longitudinal ligament which is stretched or tears, as the head snaps forward and then back again causing a whiplash injury.
A whiplash injury from an automobile accident is called a cervical acceleration-deceleration injury. Cadaver studies have shown that as an automobile occupant is hit from behind, the forces from the seat back compress the kyphosis of the thoracic spine, which provides an axial load on the lumbar spine and cervical spine. This forces the cervical spine to deform into an S-shape where the lower cervical spine is forced into a kyphosis while the upper cervical spine maintains its lordosis. As the injury progresses, the whole cervical spine is finally hyper-extended.
Whiplash may be caused by any motion similar to a rear-end collision in a motor vehicle, such as may take place on a roller coaster or other rides at an amusement park, sports injuries such as skiing accidents, other modes of transportation such as airplane travel, or from being hit, kicked or shaken.Shaken baby syndrome can result in a whiplash injury.
Whiplash associated disorders sometimes includes injury to the cerebrum. In a severe cervical acceleration-deceleration syndrome, a brain injury known as a coup-contra-coup injury occurs. A coup-contra-coup injury occurs as the brain is accelerated into the cranium as the head and neck hyperextend, and is then accelerated into the other side as the head and neck rebound to hyper-flexion or neutral position.
Whiplash symptoms might not always have any pathological (injury) explanation. "Volunteer studies of experimental, low-velocity rear-end collisions have shown a percentage of subjects to report short-lived symptoms", which cannot be attributed to any pathogenic effect on the subject's neck.
A 1000 case four year observational study published in 2012 said that the "missing link" in whiplash injuries is the trapezius muscle which may be damaged through eccentric muscle contraction during the whiplash mechanism described above and below.
Read more about this topic: Whiplash (medicine)