Lumbar spondylosis is an age-related degeneration of the vertebrae and discs of the lower back. These changes are often called degenerative disk disease and osteoarthritis. The common condition is marked by the breakdown of one or more of the disks that separate the bones of the spine. The disks provide cushioning between the vertebrae and absorb pressure put on the spine. Although most people experience some degeneration of the spine as they age, not everyone experiences back pain.