Narrowing of the spinal canal which can result in compression of the nerves contained within the canal is called spinal stenosis. It is usually a degenerative condition, that is, a condition caused by years of wear and tear on the mobile elements of the spine. It is thus a condition associated with aging. Thickening of the ligaments, bulging of the discs, and bone spurs arising from the facet joints can all contribute to spinal stenosis. Typical symptoms are pain, numbness, and weakness in the legs brought on by standing and walking and relieved by sitting or lying. The condition is often progressive, and can lead to severe disability and inability to walk more than short distances.

Lumbar stenosis is diagnosed by symptoms and imaging studies of the spine (X-rays, CT, MRI), and ruling out other contributory conditions such as vascular impairment or peripheral neuropathy. Mild cases can often be treated with proper exercise and posture. Steroid injections into the spinal canal (epidural injections) are usually helpful for a period of time. Decompressive surgery (laminectomy) is indicated in severe cases unresponsive to conservative management. Often these operations may necessitate a fusion of the spine, depending on the individual circumstances of the condition.