Stenosis is a narrowing or decreased diameter of a passage-way or an orifice in the body through which a sensitive element such as a nerve is passing. The orifice or canal may be modified and its diameter become constricted. This can cause constriction of a nerve which passes through the canal. When nerves are constricted in the spinal canal, a compression of the vessels which are supplying nourishment to the nerve get compressed. The combination of compression on the vessels and the nerve can lead to symptoms such as pain, numbness, tingling, weakness and unsteadiness.
Degeneration is thus a result of wear and tear on the spine.
With aging, the discs and ligaments of the spine become less functional. These intervertebral binders which are necessary to insure normal spinal movements to be smooth begin to decrease in function. When the disc becomes degenerated, it looses the ability to act as a shock absorber between two vertebrae as well as to be a binder bonding the two vertebrae together. The disc thickness thus decreases and its outer layer buckles or bulges. When the facet joints degenerate, the size of each facet is increased by development of bone which is formed due to cartilage wear.