The neck (cervical spine) is composed of vertebrae that begin in the upper torso and end at the base of the skull. The bony vertebrae along with the ligaments (which are comparable to thick rubber bands) provide stability to the spine. The muscles allow for support and motion. The neck has a significant amount of motion and supports the weight of the head. However, because it is less protected than the rest of the spine, the neck can be vulnerable to injury and disorders that produce pain and restrict motion.

Because the neck is so flexible and because it supports the head, it is extremely vulnerable to injury. Motor vehicle or diving accidents, contact sports, and falls may result in neck injury. The regular use of safety belts in motor vehicles can help to prevent or minimize neck injury. A “rear end” automobile collision may result in hyperextension, a backward motion of the neck beyond normal limits, or hyperflexion, a forward motion of the neck beyond normal limits. The most common neck injuries involve the soft tissues: the muscles and ligaments. Severe neck injuries with a fracture or dislocation of the neck may damage the spinal cord and cause paralysis.

The seven bones in the neck are the cervical vertebrae. They support the head and connect it to the shoulders and body. A fracture, or break, in one of the cervical vertebrae is commonly called a broken neck.

Cervical fractures usually result from high-energy trauma, such as automobile crashes or falls.

Any injury to the vertebrae can have serious consequences because the spinal cord, the central nervous system’s connection between the brain and the body, runs through the center of the vertebrae. Damage to the spinal cord can result in paralysis or death. Injury to the spinal cord at the level of the cervical spine can lead to temporary or permanent paralysis of the entire body from the neck down.

Neck sprains and strains are the most frequently reported injuries in US insurance claims. In 2007, an estimated 66 percent of all insurance claimants under bodily injury liability coverage and 57 percent under personal injury protection coverage — two important insurance injury coverages — reported minor neck injuries. For 43 and 34 percent of bodily injury liability and personal injury protection claimants, respectively, neck sprains or strains were the most serious injuries reported. The cost of the claims in which neck pain was the most serious injury was about $8.8 billion, representing approximately 25 percent of the total dollars paid for all crash injuries combined.

Whiplash

Whiplash-a soft tissue injury to the neck-is also called neck sprain or neck strain. It is characterized by a collection of symptoms that occur following damage to the neck, usually because of sudden extension and flexion. The disorder commonly occurs as the result of an automobile accident and may include injury to intervertebral joints, discs and ligaments, cervical muscles, and nerve roots. Symptoms such as neck pain may be present directly after the injury or may be delayed for several days. In addition to neck pain, other symptoms may include neck stiffness, injuries to the muscles and ligaments (myofascial injuries), headache, dizziness, abnormal sensations uch as burning or prickling (paresthesias), or shoulder or back pain. In addition, some people experience cognitive, somatic, or psychological conditions such as memory loss, concentration impairment, nervousness/irritability, sleep disturbances, fatigue, or depression.

Whiplash injuries can be sustained in any type of crash but occur most often in rear-end collisions. Based on National Automotive Sampling System data, the National Highway Traffic Safety Administration (NHTSA) estimated that there were 805,581 whiplash injuries occurring annually between 1988 and 1996. Of these injuries, NHTSA estimated that 272,464 occurred as a result of a rear impact. A 1999 Institute study found that 26 percent of drivers of rear-struck vehicles reported neck injuries to their insurance company. This was about the same as the 24 percent neck injury rate reported in a 1972 Institute study. Estimates of neck injury rates in other studies have ranged from 7 to 37 percent, depending on whether police or motorists reported the information.