Ask the Doctors January 2004 Issue

Ask Dr. Marks: 01/04

I hear more and more about lumbar stenosis being a common problem with seniors. What exactly is it and what is the suggested therapy or cure if one exists?

Lumbar spinal stenosis is the narrowing of the spinal canal, which is usually the result of spinal arthritis. The spinal canal contains both the spinal cord and nerve roots, and narrowing of the spinal canal can compress these nerve roots, resulting in pain. With an aging U.S. population, it has become an increasingly prevalent problem in older individuals.

Typically, patients complain of pain radiating down their legs, which is increased with exercise and relieved by rest. The pain is made worse by bending backward, but is markedly relieved by bending forward. This is because the spinal canal will increase in size as you bend forward. Patients with spinal stenosis can only walk a limited distance and then must rest. Paradoxically, if they swim or use an exercise cycle, their endurance is markedly greater than if they stand or walk.

The diagnosis of spinal stenosis is both clinical and radiographic. The mere fact that a patient has radiographic evidence of a small spinal canal does not mean that he or she has lumbar spinal stenosis that will need treatment. The treatment of spinal stenosis has become increasingly surgical. If patients are significantly disabled from doing the things they must do or like to do, then they are candidates for surgery—the goal of which is to increase the size of the spinal canal by removing the bone around the neural elements. Occasionally, in concert with the decompression of the spinal nerves, the spine needs to be fused to prevent instability.


I've had hip replacement recently and I am now considering a knee replacement. How many years can I look forward to after undergoing either a knee or a hip replacement before experiencing pain again?

With the introduction of new plastics and ceramics, the expected length of time before revision surgery becomes necessary has increased dramatically. It was originally thought that total hip and total knee replacements would last l0 to 12 years. However, with improvements in design and materials, we can expect a total joint replacement to last 15 to 20 years or even longer. The wear characteristics of the new materials are dramatically superior to polyethylene, which was used in the 1970s and 1980s. How long they will last in an individual patient depends on many factors, the two most important being activity level and obesity. However, it is safe to say that they will last longer than previous generations of total joint replacements.


I am currently taking an angiotensin-converting enzyme (ACE) inhibitor for high blood pressure. I also take ibuprofen to relieve my arthritis pain. I'm told that the combination may cause kidney damage. Is this true?

It is true that either ACE or ibuprofen can cause acute renal failure. Ibuprofen has also been linked to chronic renal failure when used in large amounts. But the two medications do not interact to cause a disproportional risk of kidney failure. People with a prior renal disease should use these drugs with caution. Your doctor may wish to follow you more closely when these drugs are used in combination, since he or she is best positioned to weigh the risks and benefits of these medications and to monitor possible side affects.

When choosing a location, you should look for other reasons for moving rather than just the climate. If you have family or friends in the area, this is a more compelling reason for a move than merely climate.