What is Spinal Stenosis?
Spinal stenosis is a narrowing of the spinal canal. There are many potential causes for spinal stenosis including aging, heredity and changes in the blood flow to the lumbar spine. The most common cause of spinal stenosis is aging combined with osteoarthritis. Spurs may develop on the bones and into the spinal canal. With heredity, if the spinal canal is too small at birth, symptoms may show up in a relatively young person.
What Are the Symptoms?
When narrowing places pressure on the spinal cord or nerve roots, there may be a slow onset and progression of symptoms. You may feel pain and difficulty when walking aggravated by activity, numbness, tingling, hot or cold feelings, weakness, or a heavy and tired feeling in the legs. People with more severe stenosis may experience abnormal bowel and bladder function as well as foot disorders.
How is It Diagnosed?
Your doctor may order one or more special tests to help confirm your diagnosis, rule out other problems and pinpoint the source of your back pain.
X-rays show the general condition of your vertebrae (bones), and are very helpful in determining the cause of pain. Although X-rays cannot reveal a ruptured disc, for instance, they may reveal a narrowed disc space that can be an indication of trouble in that area of the spine.
MRIs (magnetic resonance imaging) and CTs (computed tomography) produce detailed computer images of soft tissues and bones.
What Do X-rays Show?
- X-rays show the bony spurs and narrowing of the inside of the canal. However, X-rays do not show nerve problems or the internal structure of the spinal cord.
- MRIs are especially beneficial for the study of soft-tissue abnormalities such as disc degeneration, protrusion or rupture. CT scans give a cross-section view of the spine and can show a bulging or ruptured disc.
- EMGs (electromyography) measure the electrical activity of your muscles' contractions and detect nerve or muscle irritation and damage.
- Bone scans can reveal abnormal bone activity.
What Other Tests Are Needed?
CT scans and MRI scans are used to reveal the relationship between nerves and the bony structure of the spine. If nerve damage or nerve irritation is suspected, EMG (electromyography) and nerve conduction studies are very helpful. Information from these tests help to locate the specific vertebrae and spinal nerves involved, allowing a diagnosis and an appropriate treatment program.