Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

What is the primary cause of spinal stenosis?

1. Tumor growth

2. Degeneration and remodeling due to normal aging/arthritis

3. Trauma to the spine

4. Inflammatory diseases

The correct answer is: Degeneration and remodeling due to normal aging/arthritis

The primary cause of spinal stenosis is degeneration and remodeling due to normal aging and arthritis. As individuals age, the spine undergoes natural wear and tear, which can include changes in the intervertebral discs, thickening of the ligaments, and the formation of bone spurs. These age-related changes can lead to a narrowing of the spinal canal and the foramina, where nerves exit the spine. This narrowing can compress the spinal cord and nerve roots, resulting in symptoms such as pain, numbness, and weakness in the limbs. While tumors, trauma, and inflammatory diseases can also lead to spinal stenosis, they are less common contributors compared to the degenerative processes associated with aging. Tumor growth can indeed compress the spinal canal but usually represents a more specific and less frequent cause. Trauma can result in acute injuries but does not generally lead to the chronic, gradual narrowing seen in degenerative spinal stenosis. Inflammatory diseases, such as ankylosing spondylitis, can cause stenosis as well, but they are not as prevalent as the degenerative changes associated with aging and arthritis. Thus, degenerative changes are the most common and overarching cause of spinal stenosis.