A herniated disc occurs when the gel-like center of a spinal disc ruptures through a weak area in the tough outer wall, similar to the filling being squeezed out of a jelly doughnut. Neck or arm pain, numbness or tingling may result when the disc material touches or compresses a spinal nerve. Treatment with rest, pain medication, spinal injections, and physical therapy is the first step to recovery. Most people improve in 6 weeks and return to normal activity. If symptoms continue, surgery may be recommended.
Anatomy of the discs
To understand a herniated disc, it is helpful to understand how your spine works. Your spine is made of 24 moveable bones called vertebrae. The cervical (neck) section of the spine supports the weight of your head (approximately 10 pounds) and allows you to bend your head forward and backward, from side to side, and rotate 180 degrees. There are 7 cervical vertebrae numbered C1 to C7. The vertebrae are separated by discs, which act as shock absorbers preventing the vertebrae from rubbing together. The outer ring of the disc is called the annulus. It has fibrous bands that attach between the bodies of each vertebra. Each disc has a gel-filled center called the nucleus. At each disc level, a pair of spinal nerves exit from the spinal cord and branch out to your body. Your spinal cord and the spinal nerves act as a “telephone,” allowing messages, or impulses, to travel back and forth between your brain and body to relay sensation and control movement.
What is a herniated cervical disc?
A herniated disc occurs when the gel-like center of your disc ruptures out through a tear in the tough disc wall (annulus). The gel material is irritating to your spinal nerves, causing something like a chemical irritation. The pain is a result of spinal nerve inflammation and swelling caused by the pressure of the herniated disc. Over time, the herniation tends to shrink and you may experience partial or complete pain relief. In most cases, if neck and/or arm pain is going to resolve it will do so in about 6 weeks.
What are the symptoms?
If you have a herniated cervical disc, you may feel pain that radiates down your arm and possibly into your hand. You may also feel pain on or near your shoulder blade, and neck pain when turning your head or bending your neck. Sometimes you may have muscle spasms (meaning the muscles tighten uncontrollably). Sometimes the pain is accompanied by numbness and tingling in your arm. You may also have muscle weakness in your biceps, triceps, and handgrip.
You may have first noticed pain when you woke up, without any traumatic event that might have caused injury. Some patients find relief by holding their arm in an elevated position behind their head because this position relieves pressure on the nerve.
What are the causes?
Discs can bulge or herniate because of injury and improper lifting or can occur spontaneously. Aging plays an important role. As you get older, your discs dry out and become harder. The tough fibrous outer wall of the disc may weaken, and it may no longer be able to contain the gel-like nucleus in the center. This material may bulge or rupture through a tear in the disc wall, causing pain when it touches a nerve. Genetics, smoking, and a number of occupational and recreational activities lead to early disc degeneration.
Who is affected?
Herniated discs are most common in people in their 30s and 40s, although middle aged and older people are slightly more at risk if they’re involved in strenuous physical activity. Only about 8% of herniated discs occur in the neck region.
Reference:
http://www.mayfieldclinic.com/PE-HCdisc.htm