Spinal stenosis (or narrowing) is a common condition that affects many adults 50 yrs old and older. This occurs when the small spinal canal, containing the nerve roots and spinal cord, becomes constricted or compressed. This can lead to a number of problems, depending on which nerves are affected. In general, spinal stenosis can cause cramping, pain or numbness in the legs, back, neck, shoulders and/or arms; a loss of sensation in the extremities; and sometimes, in rare cases, problems with bladder or bowel function. In general, spinal narrowing is caused by osteoarthritis, or "wear and tear" arthritis, of the spinal column. This results in a "pinching" of the spinal cord and/or nerve roots.
People suffering from spinal stenosis may have trouble walking any significant distance, and usually must sit or lean forward over a grocery cart, countertop or assistive device such as a walker.
Typically, a person with spinal stenosis complains about developing tremendous pain in the legs or calves and lower back after walking. Pain occurs more quickly when walking up hills. This is usually very reproducible and is almost immediately relieved by sitting down or leaning over. When the spine is flexed forward, more space is available for the spinal cord, causing a reduction in symptoms.
What causes it?
Spinal stenosis is usually caused by progressive degenerative changes in the spine. This is usually called "acquired spinal stenosis" and can occur from the narrowing of space around the spinal cord due to bony overgrowth (bone spurs) from osteoarthritis, combined with thickening or calcification of one or more ligaments in the back. Stenosis can also be caused by a bulge or herniation of the intervertebral discs. This must be differentiated from the stenosis caused by the bony overgrowth that can occur on the vertebral bodies, or facet joints. Spinal decompression therapy may not be appropriate in moderate to severe cases of spinal stenosis with many spurs and thickened ligaments. On the other hand, if the stenosis of the central canal is primarily from bulging discs, or herniated discs, then non-surgical spinal decompression may be very successful.
Sometimes people are born with a smaller spinal canal. This is called "congenital spinal stenosis" and may become problematic at an earlier age.
Who gets it?
The risk of developing spinal stenosis increases in those who:
- Are born with a narrow spinal canal
- Are female
- Are 50 years of age or older
- Have had previous injury or surgery of the spine
Conditions that can cause spinal stenosis include:
- Osteoarthritis and osteophytes (bone spurs) associated with aging
- Inflammatory spondyloarthritis
- Spinal tumors
- Paget's disease of the bone
- Previous surgery
How is it treated?
Typically, spinal stenosis is treated with conservative non-surgical therapies. One important therapy is exercise. Keeping the muscles of the hip, back, and legs toned allows for improved stability and will improve walking.
Medications such as nonsteroidal anti-inflammatories (NSAIDs) also may be appropriate and helpful in pain relief. Cortisone injections into the epidural space, the area around the spinal cord, may provide temporary relief to people suffering from this disorder.
Non-surgical spinal decompression therapy may help those with herniated or bulging discs, lateral canal stenosis, and facet syndrome.
Under severe and rare circumstances, surgery to correct this disorder may be appropriate. In these severe cases, nerves to the bladder or bowel may be affected, leading to partial or complete urinary or fecal incontinence. If you experience either of these problems, seek immediate medical care! Decompression laminectomy, which is the removal of a build-up of bony spurs or increased bone mass in the spinal canal, can free up space for the nerves and the spinal cord. However, adequate decompression of the neural elements and maintenance of bony stability are necessary for a good surgical outcome for patients with spinal stenosis.
Several studies report that surgical treatment produces better outcomes than non-surgical treatment in the short term. However, these results tend to deteriorate over time. In addition, lumbar decompressive surgery can be complicated by epidural hematoma, deep venous thrombosis, dural tear, infection, nerve root injury and recurrence of symptoms.