Causes of Lumbar Spinal Stenosis

Lumbar spinal stenosis is mainly characterized by reduced space within the lumbar spinal canal, leading to compression of the nerve roots or spinal cord. The main causes include the following:

1. Degenerative factors: Prolonged sitting, working at a desk, and long-term heavy loading on the lower back can easily lead to lumbar osteophyte formation, ligament hypertrophy, and ossification, which subsequently reduce the effective volume of the lumbar spinal canal, resulting in lumbar spinal stenosis.

2. Lumbar disc herniation: A protruding intervertebral disc occupies the effective space of the spinal canal, compressing the nerves. This is also a common cause of lumbar spinal stenosis.

3. Developmental factors: Some patients, due to congenital factors such as a short anteroposterior diameter of the spinal canal or short pedicles, have a smaller effective volume in the spinal canal. Combined with degeneration and osteophyte formation, this predisposes them to develop lumbar spinal stenosis.

4. Hypertrophy of the ligamentum flavum: The ligamentum flavum connects adjacent vertebral laminae. With aging, the ligamentum flavum may thicken and protrude into the spinal canal, further reducing the available space.

5. Spondylolisthesis and instability: Lumbar spondylolisthesis or instability can also reduce the space within the spinal canal. Anterior slippage particularly reduces the anteroposterior diameter of the spinal canal directly.

6. Trauma or post-surgical changes: Severe trauma or surgery involving the lumbar spine may lead to scarring of local tissues, causing spinal canal stenosis.