Spinal stenosis is a narrowing of the spinal canal, which can put pressure on your spinal cord and the nerves that travel through the spine. Spinal stenosis occurs most often in the neck and lower back. Narrowing occurs when the growth of bone or tissue reduces the size of the openings in the spinal bones. This narrowing can squeeze and irritate the nerves that branch out from the spinal cord. It can also squeeze and irritate the spinal cord itself. This may cause pain, numbness, stiffness, or weakness, in the legs, feet, or buttocks. It may also cause problems with bladder or bowel function.