Lumbar spinal stenosis is a narrowing of the spine in the lower part of your back. Stenosis, which means narrowing, happens when your vertebrae, or the bones of your back, put pressure on your spinal cord or the nerves that pass out from your spinal cord to your muscles. Your spinal cord is a bundle of nerves that runs through a tunnel formed by your vertebrae called the spinal canal.
Spinal stenosis can happen in any part of your spine but is most common in the lower back. This part of your spine is called your lumbar area. Five lumbar vertebrae connect your upper spine to your pelvis.
If you have lumbar spinal stenosis, you may have trouble walking distances or find that you need to lean forward to relieve pressure on your lower back. You may have pain or numbness in your legs, or you may have difficulty controlling your bowel and bladder. There is no cure for lumbar spinal stenosis, but you have many treatment options.
The most common cause of spinal stenosis is osteoarthritis, the gradual wear and tear that happens to your joints over time. Spinal stenosis is common because osteoarthritis begins to cause changes in most people’s spine by age 50. That's why most people who develop symptoms of spinal stenosis are 50 or older. Women have a higher risk of developing spinal stenosis than men.
Besides osteoarthritis, other conditions or circumstances can cause spinal stenosis:
Narrow spinal canal
Injury to the spine
Certain bone diseases
Past surgery of the spine
Lumbar spinal stenosis can affect the spine in three ways:
The spinal cord can be squeezed in the spinal canal.
The space between vertebrae can decrease and put pressure on the nerves leaving the spine.
The bony canals that the nerves pass through when leaving the spine can become narrowed.
A combination of any of these conditions may cause symptoms of spinal stenosis.
Early lumbar spinal stenosis may have no symptoms. In most people, symptoms develop gradually over time. Common symptoms may include:
Pain in the back
Burning pain going into the buttocks and down into the legs (sciatica)
Numbness, cramping, or weakness in the legs
Loss of sensation in the feet
A weakness in a foot that causes the foot to slap down when walking ("foot drop")
Loss of sexual ability
Pressure on nerves in the lumbar region can also cause more serious symptoms known as cauda equine syndrome. If you have any of these symptoms, you need to get medical attention right away:
Loss of bowel or bladder control
Severe or increasing numbness between your legs, inner thighs, and back of the legs
Severe pain and weakness that spreads into one or both legs, making it hard to walk or get out of a chair
To diagnose lumbar spinal stenosis, your doctor probably will ask you questions about your symptoms and do a complete physical examination. During the physical examination your doctor will look for signs of spinal stenosis such as loss of sensation, weakness, and abnormal reflexes.
These tests help make a diagnosis:
X-rays of your lumbar spine. These may show bone growths called spurs that push on spinal nerves and/or narrowing of the spinal canal.
Imaging tests. A CT scan or MRI scan can give a more detailed look at the spinal canal and nerve structures.
Other studies. Your doctor might order a bone scan, myelogram (a CT taken after injecting dye), and EMG (an electrical test of muscle activity).
If you have lumbar spinal stenosis, many kinds of medical practitioners can help you, such as arthritis specialists, nerve specialists, surgeons, and physical therapists. Treatment can include medication, physical therapy, and surgery. Except in emergency situations, such as cauda equine syndrome, surgery is usually the last resort.
Medications may include nonsteroidal anti-inflammatory drugs, which relieve pain and swelling, and steroid injections that reduce swelling.
Physical therapy may include exercises to strengthen your back, abdominal, and leg muscles. Learning how to do activities safely, using braces to support your back, stretching, and massage may also be helpful.
Surgical treatments include removing bone spurs and widening the space between vertebrae. The lower back may also be stabilized by fusing together some of the vertebrae.
Acupuncture and chiropractic care are among the other treatments that may be helpful for some people.
Because almost everyone has some osteoarthritis of the spine by age 50, you can’t really prevent lumbar spinal stenosis. But you may be able to lower your risk. Here are some ways to keep your spine healthy:
Get regular exercise. Exercise strengthens the muscles that support your lower back and helps keep your spine flexible. Aerobic exercises like walking, swimming, cycling, and weight training are all good for your back.
Maintain good posture. Learn how to safely lift heavy objects. Also, sleep on a firm mattress and sit in a chair that supports the natural curves of your back.
Maintain a healthy weight. Excess weight puts more stress on your back and can contribute to developing symptoms of lumbar spinal stenosis.
The best way to manage lumbar spinal stenosis is to learn as much as you can about your disease, work closely with your medical team, and take an active role in your treatment.
Keep your lower back as healthy as possible by maintaining a healthy weight, practicing good body mechanics, and getting regular exercise.
Simple home remedies like an ice bag, heating pad, massage, or a long, hot shower can help. The nutritional supplements glucosamine and chondroitin have been recommended as nutritional supplements for osteoarthritis, but recent studies have been disappointing. Ask your heath care provider if you should try any nutritional supplements and discuss any alternative treatments or medications you’re thinking about trying.