by Donna Werner in OrthoKinetic Review magazine, January 2001

Most often caused by aging, lumbar spinal stenosis (LSS) can be managed with appropriate treatment.

OKR: What is lumbar spinal stenosis?

DR. DELAMARTER: Lumbar spinal stenosis is narrowing of the spinal canal, the region that houses all the nerve roots that innervate the lower back, buttocks, legs, and feet. When that canal narrows, it puts pressure on the nerve roots and causes a variety of problems. This condition is most often caused by simple aging, which is accompanied by changes involving bony spurring and degenerating discs in the spine. This combination narrows the canal, resulting in spinal stenosis.

DR. RASHBAUM: This narrowing can also be caused by a variety of other things including a tumor, infection, bony overgrowths, arthritis, disc herniation, or spinal deformity.

DR. DELAMARTER: Another cause can be forward slippage of the vertebrae, known as spondylolisthesis. This condition is very common and seen more often in women. While stenosis can be due to a variety of factors, most often it is the result of simple aging.

OKR: What are some of the symptoms of LSS?

DR. RASHBAUM: This is typically a diagnosis made in geriatric patients in their 60s, 70s, and 80s, and the hallmark symptom is their significant inability to walk for any distance. They may also have a perception of weakness and sometimes burning in the lower extremity, but they can sit and ride a bike forever, so you know the problem isn't in their legs.

DR. DELAMARTER: Patients often present with low back pain and pain in the buttocks, which can radiate down either one or both legs. The pain typically comes on after walking or standing and tends to get better quickly when the patient sits or lies down, and the symptoms generally lessen on forward flexion.

DR. RASHBAUM: That's right - these patients can walk around a store, as long as they are leaning on a shopping cart. That affords them just enough flexion to open up the spine, reduce pressure on the nerves, and alleviate their symptoms.

DR. DELAMARTER: However, this same patient couldn't stand upright without support for more than 30 seconds.

OKR: So this is generally a chronic condition?

DR. DELAMARTER: Correct, it generally is not an acute condition. While the patent may have acute exacerbations, for example with a fall or some other type of trauma, for the most part, the process progresses slowly over months to even years.

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OKR: How is the diagnosis of lumbar spinal stenosis made?

DR. RASHBAUM: The most reasonable way is through an MRI, since that eliminates the exposure to X-rays. We an also use a myelogram CT Scan Either of these methods shows the anatomic narrowing at various areas, depending upon the extent of the disease.

DR. DELAMARTER: A good physical exam and plain X-rays can also prove to be invaluable.

OKR: Are there different classifications of LSS?

DR. RASHBAUM: Basically its categorized as mild, moderate, or severe, depending on the amount of the actual compression. We generally consider a spinal canal of 16 to 22 millimeters to be normal. So less than 16 millimeters is considered mild and 5 to 7 millimeters is classified as severe. However, patients with very severe stenosis may or may not have symptoms. When graduated compression occurs over time, the structure - namely, the nerve root - accommodates up to a point. It's ironic - patients with small disc herniations come into our office in so much agony that they can't move, but we see patients with complete occlusion and a few symptoms and wonder how they are walking around.

OKR: What are some of the differential diagnoses for this condition?

DR. DELAMARTER: People can also get the same type of leg pain from different vascular problems, for example if they have blockage of the arterial system feeding the legs, or intermittent claudication. This often results in pain upon exercise.

DR. RASHBAUM: And you have to look at the differences between vascular claudication and spinal claudication, which produce the same symptoms. The first is just the result of decreased oxygen due to lack of blood flow to the legs, while the other is a decrease in blood flow to the nerves that innervate the muscles. Other possible differential diagnoses to look at include vitamin deficiencies, especially B6 and B12, peripheral or diabetic neuropathies, muscular dystrophy, multiple sclerosis, or even lead poisoning. These aren't common, but they are a consideration. OKR: Are there any emergency situations with LSS?

DR. DELAMARTER: Definitely. The same nerve roots affected by the stenosis also control bowel and bladder function, and when these nerves become involved, you have an emergency situation. The patient needs to seek treatment immediately. These cases are fairly rare, but they do require urgent care.

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OKR: What are the initial steps in treating LSS?

DR. DELAMARTER: Once the diagnosis is made, the majority of patients are helped immensely with conservative treatment. We start with an anti-inflammatory: an over-the-counter drug, such as Advil or Aleve or even a prescription medication like Celebrex, which is a Cox-2 inhibitor. Adding some type of physical therapy can also benefit patients. I generally start with a course of physical therapy three times per week for four to six weeks, which often improves some of the symptoms. Occasionally, I add some type of corset or low-back brace, especially if there is evidence of slippage of the vertebrae.

OKR: And what if this approach doesn't alleviate their symptoms?

DR. DELAMARTER: If we need relief beyond these more conservative measures, the next step is to become slightly invasive by injecting a steroid medication directly into the low back. This tends to settle down the inflammation and result in pretty good symptom relief.

DR. RASHBAUM: We start with a series of fluoroscopic epidural cortisone injections - one every two weeks for a period of six weeks; about half the patients do well with these. We can repeat this course as soon as five to six months after the first series without any adverse effects. If patients do not get relief after this we look at what is the most appropriate type of surgery.

OKR: At what point do you resort to surgery?

DR RASHBAUM: First, we have to consider quality of life issues. The need for surgery is always dependent on the patient's ability to respond to conservative care, and the demands of these patients often are not significant. If I have a 75-year-old patient, she may just want to be able to walk to her daughter's house to play with her grandchildren. So in most cases, we try not to operate. While surgery can be quite beneficial, the age of most of these patients make its fraught with problems, putting us in a catch-22 situation. The bone may be so soft that the metal appliances won't hold and fusion won't be successful; then we just end up trading one type of pain for another. Surgery can result in incredible instability in some patients. Now on the other hand, if you have a robust 75-year-old, surgery is a very reasonable alternative.

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OKR: Dr. Delamarter, when do you consider surgery necessary?

DR. DELAMARTER: There are two main considerations for surgery: symptoms and neurological manifestations. First, we generally move toward surgery when the patients' symptoms become incapacitating. Once their lifestyle is significantly affected - they can't do the activities they want to do, they can't walk or stand without significant pain, and conservative measures just are not helping any longer help - then surgery is an excellent option. On the other hand, if the patient is starting to exhibit significant neurological problems, such as progressive numbness and tingling in the lower extremities, or bladder or bowel dysfunction, we move to surgery immediately.

DR. RASHBAUM: One procedure that's minimally invasive is spinal-cord stimulation. We introduce a wire through a needle to an internalized generating system. A neurological pacemaker - which is an implantable device - sends out electrical signals that block the transmission of pain to the spinal cord. Its internalized battery may fail after a certain amount of time, and then a new battery is implanted. If we need to go to full-blown surgery, there are two flavors: decompression of the stenotic area with, or without, spinal fusion.

OKR: What is involved in decompression?

DR. DELAMARTER: Microsurgical decompression uses a small incision in the lumbar region and then a microscope to remove bone spurs, thus alleviating pressure on the roots. This procedure is safe and quick and only takes about an hour to an hour and a half with minimal blood loss. Most patients go home within a day or two and can begin walking almost immediately. If they have a desk job, they can generally return to work within seven to 10 days. The majority of spinal stenosis patients can be handled in this fashion.

OKR: What about more extensive surgery?

DR: RASHBAUM: With a laminectomy - or when we "take the root off" - we make a long incision and the process involves a lot of bone work. This is typically not a walk in the park for several reasons. The patient's dura can attenuate, meaning it can become flimsy and tear. You also have the risk of infection and severe instability depending on the quality of the patient's bone. Another significant operation is spinal fusion where we use metallic appliances to weld the bone together and maintain alignment as the fusion bone mass consolidates.

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DR. DELAMARTER: While a smaller number of patients need to be handled in this manner, we see the need for fusion more often when slippage is involved. Fusion can affect two vertebrae or extend to as many as three or four segments. We follow up at about six weeks, and by six months after surgery, patients are generally back to normal. Only about 10 percent have a recurrence of stenosis and require further intervention.

OKR: So you would advise patients that this condition is fairly manageable?

DR RASHBAUM: The real take-home message with LSS is that patients and practitioners really have to weigh the risks versus the benefits of surgical treatment. Sometimes as surgeons, we do things for very good reasons, which may result in an inappropriate result. Treatment can be risky in some patients due to their age, so keep in mind when you're working in these gardens, the plants don't have good roots, so to speak. If patients can be managed by pain control without significantly affecting their lifestyle, that may be the best approach.

About the Interviewees
Rick B. Delamarter, MD, a board-certified orthopedic surgeon, is medical director of The Spine Institute in Santa Monica, California, a premier facility for the treatment of neurospinal disorders. Dr. Delamarter has authored more than 200 articles, book chapters, and abstracts on spinal disorders, and is the recipient of several national and international research awards, including the 1991 Volvo Award from the International Society for the Study of the Lumbar Spine; the 1991 New Investigator Recognition Award from the Orthopedic Research Society; and the 1991 Acromed Award from the North American Spine Society.

Ralph F. Rashbaum, MD, a board-certified orthopedic surgeon, specializes in spinal surgery and the treatment of patients with chronic pain. He is the medical director and cofounder of the Texas Back Institute, one of the largest, freestanding spine facilities in the country, which offers a full spectrum of services to treat neck and back pain. In addition to developing several new surgical protocols and technologies for spinal disorders, Dr. Rashbaum has authored numerous research papers and is actively involved in TBI's spine fellowship program.

About the Author
Donna Werner is a contributing writer for OrthoKinetic Review.

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