Your Definitive Spinal Stenosis Resource
What is Spinal Stenosis?
Spinal Stenosis is the narrowing of the nerve openings either around the spinal cord or nerve roots that can cause symptoms similar to a pinched nerve; pain is described either as an aching or an electrical feeling down the arm.
Some patients are born with this narrowing, but most often spinal stenosis is the result of a degenerative condition that develops in people over the age of 50. Younger people with a spine injury or a narrow spinal canal are also at risk. Spinal stenosis is the gradual result of aging and "wear and tear" on the spine from everyday activities. Degenerative or age-related changes in our bodies can lead to compression of nerves (pressure on the nerves that may cause pain and/or damage). This crowding of nerve fibers results in pain and numbness in the back and legs when standing or walking.Your spine consists of a column of 24 bones called vertebrae that extend from your skull down to your hips. Between the vertebrae are discs of soft tissue. The vertebrae join together like links in a chain, providing support for your head and body while the discs act as cushions, or "shock absorbers." In addition to providing support, the spine encloses and protects a cylinder of nerve tissues called the spinal cord. The spinal cord is surrounded by a bony channel called the spinal canal. Normally there is space between the spinal cord and the borders of the spinal canal so that the nerves are free and are not pinched.
What causes spinal stenosis?
Your spine, or backbone, protects your spinal cord and allows you to stand and bend. Spinal stenosis causes narrowing in your spine. The narrowing can occur at the center of your spine, in the canals branching off your spine and/or between the vertebrae, the bones of the spine. The narrowing puts pressure on your nerves and spinal cord and can cause pain. Spinal stenosis is the gradual result of aging and "wear and tear" on the spine from everyday activities. Degenerative or age-related changes in our bodies can lead to compression of nerves (pressure on the nerves that may cause pain and/or damage).
As we age:
the ligaments of the spine can thicken and calcify (harden from deposits of calcium) - bones and joints may also enlarge
- bone spurs, called osteophytes, may form
- discs may collapse and bulge (or herniate)
- one vertebra may slip over another (called spondylolisthesis)
If you suffer from lumbar spinal stenosis you may feel various symptoms, including:
- dull or aching back pain spreading to your legs
- numbness and “pins and needles” in your legs, calves or buttocks
- weakness, or a loss of balance, and
- a decreased endurance for physical activities
Symptoms increase after walking a certain distance or standing for a time. Symptoms can improve when you:
- sit
- bend or lean forward (see Figure below)
- lie down, or
- put your foot on a raised rest
How would I know if I had spinal stenosis?
Diagnosing Lumbar Spinal Stenosis
Before confirming a diagnosis of stenosis, it is important for your doctor to rule out other conditions that may produce similar symptoms. In order to do this, most doctors use a combination of techniques, including:
- History - Your doctor will begin by asking you to describe any symptoms you have and how the symptoms have changed over time. Your doctor will also need to know how you have been treating these symptoms, including medications you have tried.
- Physical Examination - Your doctor will then examine you and check for any limitations of movement in your spine, problems with balance, and signs of pain. Your doctor will also look for any loss of reflexes, muscle weakness, sensory loss, or abnormal reflexes.
- Tests - After examining you, your doctor may use a variety of tests to confirm the diagnosis. Examples of these tests include:
- X-ray - shows the structure of the vertebrae and the outlines of joints.
- MRI (Magnetic Resonance Imaging) - provides a three-dimensional view of our back and can show the spinal cord, nerve roots, and surrounding spaces, as well as signs of degeneration, tumors or infection.
- CAT Scan (Computerized Axial Tomography) - depicts the three-dimensional shape and size of your spinal canal and bony structures surrounding it.
- Myelogram - highlights the spinal cord and nerves after a dye is injected into your spinal column, which appears white on an X-ray film (Precaution: Radiological evidence of stenosis must be correlated with your symptoms before the diagnosis can be confirmed.)