Spinal stenosis is a prevalent condition characterized by the narrowing of spaces within the spinal column. This narrowing can exert pressure on the spinal cord and the nerves branching out from it. It is a widespread condition, impacting many individuals globally.
What is Spinal Stenosis?
Spinal stenosis involves the constriction of the spinal canal or the openings where nerve roots exit the spine, known as foramina. This reduction in space can compress neural structures, leading to discomfort. The condition most commonly manifests in two primary areas of the spine.
Cervical stenosis occurs in the neck region. Lumbar stenosis, found in the lower back, is the most frequently encountered form of the condition. In both instances, the underlying issue is a reduction in the available space for the spinal cord or nerves.
Global Prevalence and Demographics
Spinal stenosis affects a substantial portion of the population, with its prevalence increasing notably with age. Globally, approximately 102 to 103 million individuals are diagnosed with spinal stenosis annually. Lumbar spinal stenosis is estimated to affect 10% to 11% of the general adult population.
Degenerative changes in the spine, which can lead to stenosis, are observed in up to 95% of individuals by age 50. The prevalence of acquired spinal stenosis rises in older age groups, reaching about 47% in individuals over 60. In the United States, roughly 1 in 1,000 people over 65 and 5 in 1,000 people over 50 are likely to experience spinal stenosis.
Radiological evidence of spinal stenosis is more common than symptomatic cases. Up to 21% of individuals over 60 show lumbar stenosis on imaging, and moderate foraminal stenosis can be present in 40% of people by age 60, increasing to about 75% in those aged 80 and older. Many individuals with these imaging findings do not experience symptoms, which makes obtaining precise prevalence data challenging. Some studies suggest a higher prevalence in women, although findings can vary.
Common Contributing Factors
Spinal stenosis primarily develops due to age-related degenerative changes within the spine. Osteoarthritis is a leading cause, where cartilage cushioning the joints breaks down. This can lead to bone overgrowth, forming bone spurs that protrude into the spinal canal and narrow the space available for nerves.
Another factor is the natural aging of intervertebral discs, which can dry out, flatten, or bulge. When the soft inner material of a disc leaks out, it forms a herniated disc that can press on the spinal cord or nerves. Ligaments, the fibrous bands that hold the spine together, can also thicken and stiffen with age due to arthritis, buckling into the spinal canal and further reducing space.
While degenerative changes account for most cases, other factors can also contribute. Some individuals are born with a congenitally narrow spinal canal, making them predisposed to the condition. Spinal injuries, tumors, certain bone diseases, or complications from previous spine surgeries can also lead to the narrowing of spinal spaces.
Living with Spinal Stenosis
Spinal stenosis can significantly affect daily life, impacting the ability to perform routine activities. The pressure on the spinal cord and nerves can lead to reduced mobility and discomfort. Simple actions like walking, standing for extended periods, or bending may become challenging.
Individuals living with spinal stenosis might find that tasks requiring specific movements, such as personal care or driving, become more difficult. This limitation in physical activity can lead to a more sedentary lifestyle. The ongoing discomfort can also contribute to feelings of fatigue.