Normally, the spinal cord and spinal nerves only take up about one-third of the space around them. But as we age, this space starts to narrow. Bone spurs, thickening of the ligaments, and disc collapse all contribute to this problem.
Stenosis may be accompanied by another problem: scoliosis. This is a curvature of the spine that develops as the supporting structures of the spine degenerate. The vertebrae start to slide sideways and rotate. This can further complicate the picture.
Although stenosis can be congenital, most of the time it is acquired. This means it develops as a result of the age-related changes mentioned. Whether or not stenosis is becoming more of a problem in today's older adults compared to previous generations is unknown. Studies to determine causes and risk factors are underway.