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Spinal Stenosis

What Is Spinal Stenosis?

Spinal stenosis is a narrowing of the spinal canal, the cavity within the vertebral column through which the spinal cord and nerves pass. Nerves leaving the spinal cord are called nerve roots; they pass through the vertebral column via small canals. Arthritic changes that cause overgrowth of vertebral bones may compress the spinal cord or the nerve roots, impairing sensation and muscle strength in the affected portion of the body. Most common among people in their 50s and 60s, spinal stenosis affects the lumbar (lower back) portion of the spine more than the cervical (neck) region. Symptoms include pain, numbness, and weakness in the neck, arms, lower back, and legs. As a result of leg weakness, people are prone to falls. Because the nerves controlling the bladder emerge from the lower spine, spinal stenosis may also cause urinary incontinence.

Who Gets Spinal Stenosis?

In the United States, back pain is reported to occur at least once in 85% of adults below the age of 50. Nearly all of them will have at least one recurrence. It is the second most common illness-related reason given for a missed workday and the most common cause of disability. Work-related back injury is the number one occupational hazard.

Spinal stenosis is most common in people over the age of 50. However, it may occur in younger people who are born with a narrowing of the spinal canal or who experience an injury to spine.


  • Back pain that may radiate to the buttocks and legs. Pain worsens with activity.

  • Numbness in the buttocks and legs.

  • Weakness in the legs when walking.

  • Back pain with loss of or changes in bowel or bladder function.

  • Balancing problems.

  • Pain in the legs exacerbated by walking/activity, signaling neurogenic claudication (inflammation of the nerves emanating from the spinal cord).

  • Insensitivity and losing sensation in back, neck, arms, and shoulders.

  • Cramping.

  • Foot disorders.

  • Less pain when leaning forward (such as on a shopping cart) or sitting.

Causes/Risk Factors

  • Disorders that involve arthritic degeneration and abnormal overgrowth of bone tissue, such as osteoarthritis or Paget’s disease, may cause spinal stenosis.
  • Age or aging of the body causes spinal stenosis.
  • Spinal stenosis can be hereditary.
  • Disc protrusions can contribute to stenosis.


  • Patient history and physical examination. Reflexes in the legs are tested to assess nerve involvement.

  • X-rays, rarely with injected dyes (myelography).

  • CT (computed tomography) scans or MRI (magnetic resonance imaging).

  • Electromyogram (EMG) and nerve conduction studies.


  • Losing weight and toning the abdominal muscles with exercise may reduce pressure on the spine. Check with your doctor before beginning any weight-loss program or new exercise regimen.

  • A lumbosacral support (a corset available at some pharmacies and medical-supply stores) may discourage motion that causes pain and help ease walking and exercise. It should not be worn all day, however.

  • Sitting in a forward-leaning position, which flexes the lower spine and relieves some of the pressure on the nerves, may be more comfortable than sitting upright.

  • Anti-inflammatory drugs or acetaminophen (Tylenol) may relieve pain.

  • Some success has been reported with the use of caudal epidural blocks—injections of pain relievers and a steroid directly into the base of the spine.

  • Acupuncture can help to relieve some of the pain for mild cases of spinal stenosis.

  • If pain prevents normal activities despite self-care and medication, surgery to relieve pressure on the nerves (decompression surgery) may be warranted. The surgeon opens the spinal column where narrowing has occurred and removes the constricting bone or fibrous tissue. The opening through which nerve roots pass may be widened; if an excessive amount of bone is removed, the affected vertebrae may be fused together to increase spinal stability. Physical therapy may aid rehabilitation.

  • Older adults with spinal stenosis may have other health conditions, such as heart disease or arthritis, that increase the risk of surgical complications. These conditions do not necessarily rule out surgery as a treatment option, however.


There is no way to prevent spinal stenosis.

When To Call Your Doctor

Call a doctor if you have persistent pain, numbness, or weakness in the back, legs, or neck, or if back pain accompanies changes in bowel or bladder function.

Reviewed by Andrew W. Piasecki, M.D., Camden Bone and Joint, LLC, Orthopaedic Surgery/Sports Medicine, Camden, SC. Review provided by VeriMed Healthcare Network.