Just read about Neck pain.

Neck pain (or cervicalgia) is a common problem, with two-thirds of the population having neck pain at some point in their lives.

Neck pain, although felt in the neck, can be caused by numerous other spinal problems. Neck pain may arise due to muscular tightness in both the neck and upper back, or pinching of the nerves emanating from the cervical vertebrae. Joint disruption in the neck creates pain, as does joint disruption in the upper back.

The head is supported by the lower neck and upper back, and it is these areas that commonly cause neck pain. The top three joints in the neck allow for most movement of the neck and head. The lower joints in the neck and those of the upper back create a supportive structure for the head to sit on. If this support system is affected adversely, then the muscles in the area will tighten, leading to neck pain.

Differential diagnosis

Neck pain may come from any of the structures in the neck including: vascular, nerve, airway, digestive, and musculature / skeletal or be referred from other areas of the body.

Major and severe causes of neck pain (roughly in order of severity) include:

Carotid artery dissection
Referred pain from acute coronary syndrome
Head and neck cancer
Infections: retropharyngeal abscess, epiglottitis, etc.
Spinal disc herniation – protruding or bulging discs, or if severe prolapse.
Spondylosis - degenerative arthritis and osteophytes
Spinal stenosis – a narrowing of the spinal canal
The more common and lesser neck pain causes include:

Stress – physical and emotional stresses
Prolonged postures – many people fall asleep on sofas and chairs and wake up with sore necks.
Minor injuries and falls – car accidents, sporting events and day to day injuries that are really minor.
Referred pain – mostly from upper back problems
Over-use – muscular strain is one of the most common causes
Whiplash
Herniated disc
Pinched nerve
Although the causes are numerous, most are easily rectified by either professional help or using self help advice and techniques.

More causes include poor sleeping posture, torticollis, head injury, rheumatoid arthritis, Carotidynia, congenital cervical rib, mononucleosis, rubella, certain cancers, ankylosing spondylitis, cervical spine fracture, esophageal trauma, subarachnoid hemorrhage, lymphadenitis, thyroid trauma, and tracheal trauma.

Treatment

Treatment of neck pain depends on the cause. For the vast majority of people, neck pain can be treated conservatively. Recommendations which help alleviate symptoms include applying heat or cold.[5] Other common treatments could include medication, body mechanics training, ergonomic reform, and physical therapy.

Conservative treatment
Exercise plus joint mobilization and/or joint manipulation (spinal adjustment) has been found to be beneficial in both acute and chronic mechanical neck disorders.Both cervical manipulation and cervical mobilisation produce similar immediate-, and short-term changes; no long-term data are available. Thoracic manipulation may also improve pain and function. Low level laser therapy has been shown to reduce pain immediately after treatment in acute neck pain and up to 22 weeks after completion of treatment in patients with chronic neck pain.

Medication
Analgesics such as acetaminophen or NSAIDs are recommended for pain.Muscle relaxants are often prescribed and are known to be effective. However, one study showed that one muscle relaxant called cyclobenzaprine was not effective for treatment of acute cervical strain (as opposed to neck pain from other etiologies or chronic neck pain).Over the counter topical creams and patches may be effective for some patients.

Surgery
Surgery is usually not indicated for mechanical causes of neck pain. If neck pain is the result of instability, cancer, or other disease process surgery may be necessary. Surgery is usually not indicated for "pinched nerves" or herniated discs unless there is spinal cord compression or pain and disability have been protracted for many months and refractory to conservative treatment such as physical therapy.