The spinal canal can narrow, usually in persons over 60 (rarely 50). It’s most common in the low back (lumbar region), causing pain or discomfort, maybe numbness or tingling in the legs, maybe weakness. Usually both legs are involved, helping distinguish it from a herniated disk (only one leg). Spinal stenosis in the neck or upper back causes neurological problems more so than pain, like weakness or tingling, which can cause dangerous permanent damage.
The main clue to lumbar spinal stenosis is that pain occurs with walking or standing, and goes away with sitting or lying down. Another excellent clue is improvement with a “shopping-cart gait” — leaning over as if pushing a shopping cart. I tell older patients to go to a supermarket, get a cart, and walk around with the back straight up. If pain occurs, keep on walking but bent over. If the pain goes away even while continuing to walk, it’s likely spinal stenosis.
Diagnosis is made by MRI. But just like herniated disks, some people without any symptoms may show “spinal stenosis.” The number of false-positives may be as high as 20% – 30% in the elderly. Imagine having surgery because of a false-positive MRI!!!
Without treatment, some people get better, some get worse, & most stay the same. Physical therapy hasn’t really been proved to help, spinal injections don’t help, & pain medicines serve only to relieve pain. Surgery can help, but also runs the risks of major complications & even death. So it’s real important to outline all this to patients, and try to determine who is / is not likely to benefit or suffer from an operation:
Likely to benefit:
- younger patients
- better health & overall functioning
- worse spinal stenosis
Likely to have problems
- poorer overall health (especially heart disease)
- scoliosis (curved spine, from childhood)
- Poor overall function
The worst complication of spinal stenosis, which is uncommon, is multiple nerve damage (“cauda equina syndrome”). Patients may have new weakness in both legs, new numbness or tingling around the anus and/or genitals, and new major with urine and bowel (can’t hold any in, or can’t go at all). This requires emergency surgery to prevent paralysis.