Lumbar spinal stenosis is a narrowing of the space surrounding the spinal cord and spinal nerves in the lower back. The spinal cord runs through a hollow space in the bones of the spine (vertebrae) called the spinal canal, beginning at the base of the brain and going to the upper part of the lower back. Spinal nerves leave the spinal cord through openings called foramen to go to other parts of the body.
If the spinal canal becomes narrowed, it’s called central stenosis or spinal canal stenosis. If the foramen becomes narrowed, it’s called foraminal stenosis.
Spinal Stenosis Causes
The most common reason for the changes that cause lumbar stenosis is degenerative arthritis due to aging. Arthritis causes the spinal joints and ligaments to become larger, making the area for the spinal cord and nerves smaller.
Other causes of spinal stenosis include:
- calcium deposits on the spinal ligaments
- inherited conditions, such as a small spinal canal or a curved spine
- Paget’s disease
- rheumatoid arthritis
- spinal tumors
- trauma, including injury and previous back surgery
Spinal Stenosis Symptoms
Many people over age 50 have signs of lumbar spinal stenosis on an X-ray but have no symptoms. Spinal lumbar stenosis becomes a problem only if the narrowing leads to pressure on the nerves or spinal cord, causing inflammation. The following symptoms may start slowly and get worse over time:
- foot problems
- loss of coordination
- numbness, weakness, cramping, or pain in the legs
- pain in the low back
- Pain going down the leg
- trouble walking long distances
One type of lumbar spinal stenosis called cauda equine syndrome is serious and requires emergency (often surgical) treatment. A person who has any of the above symptoms and also experiences loss of bowel or bladder control or has problems having sex should contact a doctor immediately.
Spinal Stenosis Treatment
According to the American College of Rheumatology, exercise is the most important lumbar spinal stenosis treatment. Keeping the muscles of the hips and legs strong helps increase stability and the ability to walk. The College suggests focusing on flexion-based exercise, along with some walking or swimming. A physical therapist can develop an exercise program tailored to specific needs.
In addition to exercise, anti-inflammatory drugs can reduce swelling and pain, and analgesics can relieve pain. Other treatments that may help include chiropractic, massage therapy, and acupuncture.
In severe cases, cortisone injections can help reduce swelling and pain. However, an injection usually only gives temporary relief and is not recommended repeatedly because of potential side effects, including the breakdown of surrounding tissue.
If other treatments do not work and the symptoms of stenosis interfere with walking, cause problems with bowel or bladder function, or cause nervous system problems, spinal stenosis surgery may become necessary. The goal of surgery is to relieve pressure by widening the spinal canal.