Cervical radiculopathy, commonly called a "pinched nerve", occurs when a nerve in the neck is compressed or irritated where it branches away from the spinal cord. This may cause pain that radiates into the shoulder, as well as muscle weakness and numbness that travels down the arm and into the hand.
Cervical radiculopathy is often caused by "wear and tear" changes that occur in the spine as we age, such as arthritis. In younger people, it is most often caused by a sudden injury that results in a herniated disk.
Cervical radiculopathy most often arises from degenerative changes that occur in the spine as we age or from an injury that causes a herniated, or bulging, intervertebral disk. As the disks in the spine age, they lose height and begin to bulge. They also lose water content, begin to dry out, and become stiffer. This problem causes settling, or collapse, of the disk spaces and loss of disk space height. As the disks lose height, the vertebrae move closer together. The body responds to the collapsed disk by forming more bone, called bone spurs, around the disk to strengthen it. These bone spurs contribute to the stiffening of the spine. They may also narrow the foramen, the small openings on each side of the spinal column where the nerve roots exit, and pinch the nerve root.