The lumbar spinal canal is the space inside the lower spine that carries nerves to your legs. It is very narrow. Over the course of many years, the bone and tissue around the canal grow, causing the canal to become even more narrow over time. This narrowing is called "stenosis." As the lumbar spinal canal narrows, the nerves that go through it are squeezed. This squeezing may cause back pain, leg pain and weakness.
Arthritis, falls, accidents, and wear and tear on the spine's bones and joints can also cause lumbar spinal canal stenosis.
Lumbar spinal canal stenosis is not the same as a ruptured disk. A ruptured or "herniated" disk usually pinches 1 or 2 nerves at a time. The pain caused by a ruptured disk in the lumbar spine is usually easy to diagnose and is known as sciatica. Sciatica usually causes back pain that shoots down one leg along the path of the sciatic nerve. Sciatica can happen any time, not just when you stand up or start walking like it does with stenosis.
People who have lumbar spinal canal stenosis may have back or leg pain or numbness. Your legs might also feel cramped, tired or weak. These symptoms usually start when you are standing or walking. Often, the symptoms get better if you sit, crouch or lie in the fetal position (with your knees tucked up to your chest). It's thought that these positions "open" the lumbar canal and take the pressure off the nerves that go to the legs.
In severe cases, stenosis can cause partial or complete bowel or bladder incontinence
Although your doctor can probably tell if you have stenosis by asking you about your symptoms, sometimes the doctor may order special tests and X-rays of the spine to make the diagnosis.
If you have lumbar spinal canal stenosis, your treatment will depend on how bad your symptoms are. If your pain is mild and you haven't had it long, you can try an exercise program or a physical therapy program. This can strengthen your back muscles and improve your posture. Your doctor may also prescribe medicine to help reduce inflammation (soreness and swelling) in your spine.
If you have more severe symptoms, you may need to see a spine surgeon. The surgeon may recommend an operation to take the pressure off the nerves in your lower spine. This surgery works well for many people.
Written by familydoctor.org editorial staff