Lumbar spinal stenosis is narrowing of the canal through which the nerves pass, due to age-related changes. It causes pain, numbness and fatigue in the legs when walking, relieved by sitting or bending forward.
What is lumbar spinal stenosis?
With age, disc wear, enlargement of the facet joints (arthritis) and thickening of the ligament at the back of the canal (ligamentum flavum) can narrow the spinal canal through which the nerves pass. This is called lumbar spinal stenosis and usually occurs over the age of 50.
As the canal narrows, the nerves become compressed, especially when standing and walking. Because bending forward slightly widens the canal, patients feel relief when they sit down or lean forward.
Symptoms
- Leg pain, numbness and fatigue that worsen with walking and ease with stopping, sitting or bending forward (neurogenic claudication)
- Progressively shorter walking distance
- Lower back pain
- Weakness and unsteadiness in the legs
- Impaired bladder control in advanced cases
Diagnosis
Lumbar MRI shows the degree and level of narrowing. Flexion-extension X-rays may be taken to assess any associated slippage or instability. It is important to distinguish it from leg pain caused by vascular disease (vascular claudication).
Treatment Approach
For mild to moderate symptoms, medication, physiotherapy, exercise and, in suitable patients, interventional pain treatments are used.
Surgical decompression is recommended for patients whose walking distance is markedly reduced, whose daily life is limited or who develop weakness. The operation widens the canal by removing the bone and ligament compressing the nerves (laminectomy or the more limited laminotomy). If there is associated slippage or instability, fixation with screws and rods (fusion) may be added.