Spinal stenosis occurs when one or more bony openings (foramina) within the spine begin to narrow and reduce space for the nerves in the spinal canal. This process can occur within the spinal canal (where the spinal cord runs down the center) and/or in the intervertebral foramina where spinal nerves exit the spinal canal. Depending on the location and how much narrowing occurs over time, a spinal nerve or the spinal cord could become compressed and cause pain, tingling, numbness, and/or weakness. 

This condition is often caused by age-related wear and tear. Some symptoms, if they occur, include pain, numbness, muscle weakness, and impaired bladder or bowel control. Treatment include medication, physical therapy, and possibly surgery.