Causes of neck pain are often grouped into broad categories such as: 

• Traumatic: the result of an injury
• Degenerative: caused by wear and tear
• Other causes: which include tumors, infection, and autoimmune disorders

Traumatic

A traumatic cause of neck pain can be the result of an injury. Some injuries are minor and can resolve spontaneously while others may require medical attention and can have a prolonged recovery.

• Muscle strain: refers to injury to the muscle or its connecting tendons. This can be caused by sudden extension or flexion, such as in whiplash, or twisting awkwardly. These are typically minor injuries that can heal with rest, physical therapy and medications.
• Fracture: a fracture is a broken bone and may be the result of a fall, or high impact injury like a car accident. In older people with osteoporosis (decreased bone density) fractures can occur with minimal trauma. Depending on where the vertebrae is broken, a fracture can be treated with rest alone, bracing, but can sometimes require surgery.

Degenerative

Degenerative causes of neck pain refer to wear and tear on the spine. This is often age related, or due to overuse and repetitive injury. Chronic neck pain is often caused by degenerative changes.

• Canal Stenosis (narrowing): the spinal cord and spinal nerves pass through canals within the spine. These can narrow due to bony overgrowth (osteophytes), thickening of ligaments (ligamentum flavum hypertrophy), or because of a herniated intervertebral disc.
• Herniated disc: The intervertebral discs can slip, protrude, or rupture which can result in canal narrowing and compression of the spinal cord or nerve roots.
• Degenerative disc disease: refers to wear and tear on the intervertebral disc. The disc can be thought of as a gel filled sac (nucleus pulposus) with a fibrous outer layer (annulus pulposus) that acts as a shock absorber. Overtime, the gel-like center can dry out and the outer layer may break down leading to pain.
• Spondylosis: is a general term that refers to age related wear and tear, or degeneration, of the spine.
• Spondylolisthesis: is when one of the bones of the spine, called a vertebrae, slips forward or backwards from its normal position.

There are other causes of neck pain that are neither due to injury or degenerative changes in the spine.

• Tumor: An abnormal growth that may be benign or cancerous. Treatment may be surgery, radiation, chemotherapy, or a combination.
• Infection: An infection can affect the bones (osteomyelitis), the discs (discitis), or the space surrounding the spinal cord (epidural abscess).
• Auto-immune disorders: Autoimmune disorders occur when your immune system misidentifies healthy cells as foreign and attacks them by mistake. Example disorders are rheumatoid arthritis and ankylosing spondylitis.

An evaluation by a medical professional is highly recommended to ensure a proper diagnosis.