Spinal Cord

The spinal cord consists of millions of nerve fibers that transmit sensory and motor signals to and from the brain. Together with the brain, the spinal cord is part of the central nervous system (CNS). It runs from the base of the skull to about the L1-L2 level of the lumbar (lower back) region of the spine, and is about the diameter of a human finger.

Anatomy of the Spinal Cord

The spinal cord is encased in three layers of membrane known as the meninges and is protected by surrounding liquid called cerebrospinal fluid. Along the length of the cord, 31 pairs of nerve roots exit through openings between the vertebrae, serving as conduits for electrical signals to and from the limbs, the trunk, and other parts of the body. At the base of the spine, the spinal cord branches off into the cauda equina, which is a horse-tail shaped cluster of nerves that innervate the lower body.

How Degenerative Conditions Affect the Spinal Cord

The spinal cord also is surrounded by the other anatomical components of the spine, including the vertebrae, ligaments, tendons, and intervertebral discs. As we age, these components begin to degenerate. This deterioration can lead to anatomical abnormalities, such as bone spurs and herniated discs, which present a potential threat to the spinal cord and nerve roots. Compression of the spinal cord or nerve roots can produce neurological symptoms including localized pain, radiating pain, tingling, numbness, and muscle weakness. These symptoms typically respond well to conservative treatment such as pain medication, exercise, and stretching, but surgery may become an option if chronic symptoms persist for several weeks or months.