The cervical spine, made up of seven bones, or vertebrae, and soft spongy discs located between each vertebra, is designed for a great deal of movement. The discs have an outer tough, fibrous layer, called the annulus and a soft jelly-like portion in the center, called the nucleus. Either through trauma or poor posture and inactivity, the disc may eventually begin to break down. In this process, the outer annulus cracks and allows a portion of the nucleus to bulge out and put pressure on nearby structures, such as spinal nerves or the spinal cord, possibly creating a variety of symptoms.
Pain, generally the first symptom noticed, can originate in several different ways. First, when a disc herniates, it causes inflammation and chemical mediators in this inflammatory process can irritate nearby spinal nerves and lead to pain. A herniated disc can also put direct pressure on the nerves, blood vessels or the spinal cord and in each case, pain results. According to the Mayfield clinic, a patient with a herniated disc may feel pain that radiates down the arm and into the hand, between the shoulder blades or only in the local area of the actual herniation.
The spinal nerves travel from the neck down the arm and into the hand and provide the sensations in the skin. In the case of a cervical herniated disc, pain will often be accompanied by numbness and tingling that can radiate in the same manner as the pain does. Patients often notice numbness and tingling in the hand and fingers and sometimes can identify a pattern that can help doctors determine which nerves are compromised.
The same spinal nerves that control sensation also control muscle activity in the arm and when a herniated disc causes dysfunction in the nerves, muscle weakness can result. Often, an individual will notice that grip strength in the hand becomes compromised. According to SpineHealth.com, the muscle that is compromised depends on which nerve has pressure on it, and doctors can determine where a herniated disc has occurred by testing the various muscles of the arm.
Pressure and irritation on a spinal nerve can lead to muscle spasm. This sustained contraction commonly happens in cases of cervical herniated disc. A therapist can treat a spasm with electrical muscle stimulation, which fatigues the muscle and breaks the contraction.
Whether caused by pain, muscle spasm or shortened muscle fibers, those with a herniated cervical disc often find that the range of motion in the neck is decreased. Treatment of the underlying condition usually improves mobility.
About this Author
Dr. Blake Biddulph received his chiropractic degree from Parker College of Chiropractic in Dallas in 2007 and has been practicing as a chiropractic physician in Provo, Utah, ever since. He has a special interest in spinal rehabilitation and treats patients with a variety of neck and back conditions. He has been writing health-related articles and newsletters for several years.