Stenosis refers to a narrowing of the spinal canal, usually in the lower back (lumbar) region. This narrowing is often a result of the normal degenerative aging process. It occurs as the discs of cartilage that separate the spine’s vertebrae lose water and the space between the vertebrae becomes smaller, causing friction between the bones.

The loss of water in the discs makes them less flexible and unable to act as shock absorbers in the spine. Daily wear and tear on the spine become more significant without these shock absorbers.