These key points are from an article titled "Chronic whiplash and whiplash-associated disorders: An evidence-based approach" from the Journal of the American Academy of Orthopedic Surgeon, October 2007
In a typical rear-end auto collision, the injury is caused by the abnormal biomechanics of neck motion resulting from the forward and upward motion of the torso while the head lags behind as the result of inertia.
The whiplash event lasts well under 500 ms. (The quickness bypasses the stretch reflex of the muscles so the joints get damaged)
Severity of property damage is not a reliable predictor of injury or outcome in low-speed collisions. Crash characteristics and human factors are much more relevant. Crash factors include: size, weight and speeds of the vehicles: type and position of the seat and head restraint; the ability of the vehicles to absorb or transmit energy. Human factors include: size, weight and sex of the occupant; awareness of impending collision; direction occupant is facing at impact; individual tissue tolerance
Those who experience acute neck pain immediately following the motor vehicle collision are 3 times more likely to report chronic neck pain 7 years later than are patients involved in car accidents who had no acute neck pain and patients not involved in a prior accident.
In 80% of whiplashash patients, their neck pain begins the day of the collision. 20% of patients who develop chronic neck pain experience a delay in time between the collision and the onset of pain. Up to 40% of whiplash injured patients develop chronic pain and 5 to 12% of whiplash injured patients experience chronic moderate to severe pain.
Chronic pain is defined as pain that persists after the resolution of structural injury, defined by these authors as pain that persists beyond 6 months.
Associate muscle and ligament injuries heal in 6 to 8 weeks, and these injuries do not cause chronic neck pain.
After neck pain, headache is the most common symptom of whiplash. These types of headaches are usually unilateral and begins at the base of the skull, radiating to the crown and front of head. Arm pain is common in post auto accident patients. Whiplash in jury can also cause: low back pain, vision disturbances, dizziness, tinnitus, weakness, fatigue, poor concentration, poor memory, sleep problems, depression.
Initially 55% of whiplash patients report low back pain. This pain remains chronic in 30 to 42% of patients at 6 months. The tissue sources for chronic low back pain from auto accidents are injury to the sacroiliac joints, low back facet joint injury, and low back discs.
Spinal manipulation (Chiropractic adjusting) is one of the most popular treatments for chronic neck pain, and it can be beneficial. Intra-articular injections of corticosteroid and cervical epidural corticosteroid injections do not work well.