Spinal Stenosis is a narrowing of the spaces in the spinal column that causes compression of the spinal cord and/or nerve roots. There are many causes. Any condition that involves structural changes or inflammation of the spine may cause compression of the spinal cord or nerve roots.
*Compression of a nerve is often referred to as a "pinched nerve."
The spinal cord (a bundle of nerves) is protected by the vertebral column (spinal column). The spinal canal refers to the space in the vertebral column for the spinal cord and its nerve roots. Nerve roots exit the spinal cord through small openings between each vertebra.
More than one area on the spine may be affected. Symptoms depend upon what area or areas of the spine are affected. There may be back pain and/or there may be pain, numbness, weakness, and cramping in the legs (when the lower spine is affected) or arms (when the neck area is affected). Symptoms often develop gradually.
Though the causes vary, this condition is most commonly caused by gradual degenerative changes in the spine that occur with aging. Spinal stenosis is most common in people over age 50. With age, bones and ligaments may thicken and disks between the vertebrae become thinner and may bulge. These structural changes may result in a narrowing of the spinal canal.
A major cause of progressive degenerative changes in the spine is osteoarthritis. In advanced osteoarthritis, bone spurs (bony growths) may form on the spinal joints and compress nerve roots. There may be inflammation in advanced osteoarthritis of the spine, narrowing the spinal canal.
An injury, a congenital narrow spinal canal, and a host of other conditions may also result in spinal stenosis. Scoliosis may cause compression of the spinal cord or nerve roots if the curve is severe.
A fracture of a vertebra can cause a piece of bone to chip off and protrude into the spinal canal. A vertebral fracture or vertebral degeneration may also result in one vertebra slipping over another (spondylolisthesis) and the misaligned vertebrae may protrude into the spinal canal.
The lower back (lumbar spine) is the area of the spine most commonly affected by spinal stenosis. Pressure on a nerve root (a "pinched nerve") in the lower spine may result in sciatica. Sciatica refers to pain along the sciatic nerve - pain that often radiates from the back, hip, or buttocks down the back of the leg and is often accompanied by numbness, tingling, or weakness in the leg and sometimes the foot.
People with spinal stenosis in the lower spine often find that leaning forward while walking or lying with knees drawn up relieves the symptoms. This is because bending forward enlarges the spaces between the vertebrae at the back of the lumbar spine and relieves pressure on the nerve roots.
If stenosis occurs in the neck area, there may be neck and shoulder pain. It may cause headaches - usually at the back of the head. There may also be numbness, weakness and tingling in the arms or hands and sometimes legs. It can also affect balance and cause an unsteady gait.
In severe cases, nerves to the bladder or bowel may be affected. A loss of bladder or bowel control warrants immediate medical attention.
Because the symptoms of spinal stenosis can be caused by other conditions, an MRI, CAT scan, or special x-ray may be required for a diagnosis.
Treatment involves treating the pain, any inflammation, and the condition that is causing the stenosis. If conservative treatment does not bring relief or there is severe neurological impairment surgery may be necessary.
If symptoms are mild, over-the-counter pain and anti-inflammatory medications may help relieve the pain. In cases of severe pain, a physician may prescribe stronger pain medications.
Back Exercises are usually recommended. A physician should always be consulted before staring an exercise program. Activities may have to be restricted if there is severe neurological impairment. Do not do too much too soon to avoid injury.
Exercises to strengthen the muscles that support the spine (back and abdominal muscles) and stretch back muscles help to keep the spine in good alignment. Shortened muscles in the lower back increase the curve in the lower back and decrease space between the back of the vertebrae, causing more pressure on the nerve roots.
Low-impact aerobic exercises are often recommended. Aerobic exercise helps keep the spine healthy. Aerobics increase circulation, spinal joint lubrication and spinal disc hydration. In most cases, degenerative changes in the spine are associated with spinal stenosis, in which case high-impact exercises are not recommended. Low-impact aerobics are easier on the joints and discs. Walking is a low-impact exercise but unfortunately walking usually increases symptoms when the stenosis is in the lumbar spine. Riding a stationary exercise bike may be preferable to walking as the bent over position increases the space between the back of the vertebrae in the lumbar spine to take pressure off nerve roots.
Some people find pain relief using complementary treatments for pain such as acupuncture, hydrotherapy, and TENS.
An epidural steroid injection, an injection of corticosteroids (powerful anti-inflammatory medication) and a local anesthetic into the epidural space (the space between the membranes covering the spinal cord and the wall of the spinal canal) may provide weeks to months of relief. The number of injections is limited due to potential side effects. Many people are frightened of corticosteroids, as they know of people who have had serious side effects from the long-term use of oral steroids such as prednisone. A local injection ensures a high dose of steroids are received where most needed while only a small amount of medication is absorbed into the blood stream. There are rare but serious risks involved with the injection itself.
The symptoms of spinal stenosis may worsen over time. If the pain becomes severe and chronic and conservative treatment does not provide relief, surgery may be recommended. Most surgery for spinal stenosis is elective surgery.
*If there great difficulty in walking or there is a sudden loss of bladder or bowel function, emergency surgery may be necessary to relieve the pressure on the spinal cord or nerves and avoid permanent nerve damage. Fortunately, this is a rare occurrence.