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.
Don’t medically investigate neck pain until it’s met at least three criteria: (1) it’s been bothering you for more than about 6 weeks; (2) it’s severe and/or not improving, or actually getting worse; and (3) there’s at least one other “red flag” (age over 55 or under 20, painful to light tapping, fever/malaise/nausea, weight loss, nasty headache, severe stiffness, very distinctive pain, and numbness and/or tingling and/or weakness anywhere else). Note that signs of arthritis are not red flags.
Injury and Accidents: Whiplash is a common injury sustained during an auto accident. This is typically termed a hyperextension and/or hyperflexion injury because the head is forced to move backward and/or forward rapidly beyond the neck's normal range of motion. The unnatural and forceful movement affects the muscles and ligaments in the neck. Muscles react by tightening and contracting creating muscle fatigue resulting in pain and stiffness.

I’ve never really considered going to a chiropractor—I’m healthy, moderately active and I don’t really have much pain on a regular basis. But I work for a health and wellness company that encourages its employees to take an active role in their health, and many of my coworkers swear by their chiropractors. I wasn’t sure what a chiropractor could really do for me, but after a bit of word-of-mouth research, I found out that chiropractic care actually has benefits for your whole body! So I decided to give it a try.
Chiropractors use hands-on spinal manipulation and other alternative treatments, the theory being that proper alignment of the body's musculoskeletal structure, particularly the spine, will enable the body to heal itself without surgery or medication. Manipulation is used to restore mobility to joints restricted by tissue injury caused by a traumatic event, such as falling, or repetitive stress, such as sitting without proper back support.