Learn more at http://www.spine-health.com/conditions/spinal-stenosis/lumbar-spinal-stenosis-a-definitive-guide
As we age, the spine changes, often leading to a degeneration of the vertebrae (bones), discs, muscles and ligaments (connective tissues) that together make up the spinal column. These changes may lead to spinal stenosis.
The term "stenosis" comes from the Greek word meaning "choking" and is often the result of degenerative conditions such as osteoarthritis and/or degenerative spondylolisthesis. When the spinal nerves in the lower back are choked, lumbar spinal stenosis occurs and most often leads to leg pain and other symptoms, as described in more detail below.