What Distinguishes Lumbar Stenosis from Lumbar Disc Herniation?

Differences Between Lumbar Spinal Stenosis and Lumbar Disc Herniation

Many people often confuse lumbar spinal stenosis with lumbar disc herniation in their daily lives, mistakenly believing they are closely related conditions affecting the lumbar spine. However, it is crucial to understand that these two conditions are fundamentally distinct, differing in their etiology, impact on the human body, and manifested symptoms. A detailed differentiation between them is essential.

1. Different Pathogenesis

The pathogenesis of lumbar spinal stenosis and lumbar disc herniation varies significantly. Lumbar spinal stenosis arises from factors such as disc protrusion, osteoarthritis of facet joints, hypertrophy of the yellow ligament, and degenerative spondylolisthesis, which narrow the diameter of the central spinal canal, lateral spinal canal, or neural foramen. This constriction, especially during walking or prolonged standing, increases intraspinal pressure, impeding venous return and causing nerve root ischemia, leading to pain. Conversely, lumbar disc herniation pain stems from inflammatory reactions triggered by disc protrusion, rupture of the fibrous ring, and exposure of the nucleus pulposus.

2. Different Age Groups Affected

Lumbar disc herniation is more prevalent among young and middle-aged adults aged 20 to 50, with a higher incidence among males. The fourth and fifth lumbar vertebrae are the most commonly affected sites, followed by the fifth lumbar vertebra and first sacral vertebra. In contrast, lumbar spinal stenosis is more common in middle-aged individuals over 40, with a gradual onset, contrasting the sudden onset often seen in central disc protrusion. The primary symptoms of lumbar spinal stenosis include low back pain, leg pain, and intermittent claudication.

3. Different Symptoms

Patients with lumbar spinal stenosis may experience no discomfort at rest but may develop radiating pain, numbness, or weakness in the lower extremities after walking or standing for extended periods. Squatting, sitting, or lying down can alleviate or eliminate these symptoms temporarily, enabling patients to walk for a certain distance before symptoms recur. This phenomenon is medically termed neurogenic intermittent claudication, and patients often find that riding a bicycle or pushing a cart in a supermarket does not exacerbate symptoms. In contrast, the radiating pain in the lower extremities caused by lumbar disc herniation is often persistent and difficult to relieve, even with squatting or lying flat.