Lower back pain

Almost everyone (eight out of 10 of us, at least) will endure at least one episode of back trouble before we shuffle off this mortal coil. Back problems are the second most common reason, after coughs and colds, that people seek medical advice, the most likely reason people under 45 aren’t able to enjoy their leisure activity of choice, and the third most common reason why people over 45 aren’t golfing, gardening or going for the gusto in their leisure hours.

While bad backs exact a heavy personal toll in our “off” hours, it’s in the workplace that the damage is actually measured. As Judylaine Fine notes in The Ultimate Back Book (Stoddart, 1997), back woes account for a third of all Workers’ Compensation Board claims. Once an injured worker’s been off work for six months, “the chances of his or her ever going back are only 75 per cent. After a year, those chances decline to 50 per cent; after two years, they’re more or less zero.” Incredibly, says Dr. Richard Deyo, a professor in the Department of Medicine and Health Services at the University of Washington in Seattle, “in spite of all our new diagnostic technology, surgical techniques, dissemination of professionals whtreat back pain, more and more friendly workplaces, fewer jobs that require manual labour back pain disability just keeps going up.”

So do the costs: Lost work days (some 9.5 million annually in Canada), medications, hospitalizations, rehabilitation and assorted costs, direct and indirect, due to back problems are estimated to drain $50 billion a year out of the North American economy.

The question is, why is a condition that affects so many of us individually and all of us as a society so ill treated and so little understood? That’s a question Judylaine Fine has been trying to answer since the early ’80s. That’s when she formed the Back Association of Canada (BAC), as a way of gathering information about her own trial by low back pain, an ordeal she’s been suffering from for the better part of 20 years. There were organizations scattered across the continent trying to educate people with back pain, she says, “but to this day BAC is the only registered charitable organization whose goal is to provide information from an unbiased point of view.” That’s about as far as it’s possible, Fine admits, to remain unopinionated on a subject which she, clearly is not — that’s fraught with controversy. Fine writes a monthly column on back pain for The Toronto Star, sits on the advisory board for the Vermont Back Research Center as she notes, “the only federally funded back pain research program in the entire USA” and is in growing demand as a speaker. She rarely misses an opportunity to sound off about the shortcomings in the care, research and treatment of back disorders.

Part of the reason why back pain doesn’t get more respect, Fine suggests, “is that, unless you’ve had it, it’s hard to sympathize. People still say and I hear this all the time ‘I used to think back pain was nothing, but, wow! You’re right. It’s really awful. It’s a terrible pain’.”

Try telling that to a doctor frustrated by his or her inability to put a finger on the source of your problem. Most doctors welcome new back patients about as much as a tax audit. Dr. Vert Mooney, Professor of Orthopedics at UCSD OrthoMed Center in La Jolla, Ca., described it well in the May 1995 issue of SPINE: State of the Art Review: “I, like every resident orthopedic surgeon in training, dreaded the low back clinic; the land of assumed psychological cripples presenting with unknowable disease plus endless series of returning patients who had had treatments that weren’t working.”

A patient with back pain, Deyo says, “was not a problem most doctors wanted to see. We shuddered when we saw a patient with back pain on our morning list. We had sort of a sense that these people become chronic and just don’t do well.”

The big dilemma is what doctors call non specific low back pain, a catch all term that implicitly acknowledges their inability to diagnose what is, after all, the majority of low back pain cases. At a Toronto conference, Deyo called that inability “a dirty little secret… we don’t like to talk about very much.” To put things in perspective, he quoted a number of so called experts “at meetings like these: One says 80 per cent of back pain is caused by weak or tense muscles. A second says the majority of low back pain… originates in the sacral ligaments. The next guy says 90 to 95 per cent of back pain is due to discs… Another one says an extremely high percentage have postural problems, and the final one says 50 to 70 per cent of the chronic symptoms are psychological in origin.”

Add ’em up, Deyo says, and it comes to “about 400 per cent of all patients with back problems. These are mutually exclusive statements. Somebody’s wrong. And I argue, in fact, that these are all merely hypotheses… Truth be known, we really don’t know what’s causing back pain.” There are a number of good reasons. Imaging techniques, for one thing plain x rays, CAT (computerized axial tomography) scans and MRI (magnetic resonance imaging) usually aren’t much help and often provide only contradictory evidence. On plain x rays, for example, degenerative changes to bone are ubiquitous (x rays don’t show soft tissue); by the age of 60, virtually everyone’s x ray reveals degenerative changes, yet not everyone has back pain. Among those who do, there’s no guarantee that the radiographic changes the doctor sees are the cause of the patient’s pain.

That scenario was verified by a Swedish study in which researchers reviewed 10 years of film. Among x rays of those aged 20 to 50, only about one in 2,500 showed something that wasn’t already suspected on the basis of medical history and physical examination.

Nor does the latest technology, MRI which does show soft tissue changes solve all of a diagnostician’s woes. “If you do MRIs in normal people,” says Deyo, “you uncover all kinds of horrible looking things.”

Deyo cites a small MRI study that looked at “normal people off the street” who’d never had back or leg pain. From the results, researchers reported that about a quarter of people under age 60 have a herniated disc; nearly half have at least one deteriorating disc; and more than half have evidence of spinal stenosis. Over age 60, more than a third of us have herniated discs, and more than 90 per cent have degenerated discs yet none of the people in the study were actually experiencing back pain.

According to the first author of the study, Deyo says, “a diagnosis based on MRI, in the absence of objective clinical findings… may not be the cause of the patient’s pain at all. An attempt to offer correction could be the first step toward disaster. I think a growing number of people believe that these imaging tests in fact may be leading to a lot of ill advised surgery.” Electronic imaging isn’t the only source of confusion. As Hall points out in The New Back Doctor, our own central nervous systems (CNS) can cloud the picture; the CNS transmits pain signals to the brain, but, and here’s the catch, it can’t always tell from which of its branches it originated: “You may have to admit, ‘I don’t know whether the pain is coming from my calf, from behind my knee or the back of my thigh.’ When that happens, you’re experiencing the phenomenon doctors call referred pain.”

Back muscles may also create pain away from the original source by reacting to irritation felt by one of the facet joints in the spine. “When the joint irritation is translated into pain by the spinal cord,” Hall writes, “the muscles at the scene of the trouble may respond by tightening up. This is a protective reaction to immobilize the irritated area and thus prevent further irritation. Ironically… this reaction may be so severe it produces pain of its own. You may not recognize this condition for what it is a muscle spasm or cramp; you may think your whole back has ‘gone out’.”

“Ninety per cent of back pain is labeled mechanical, and of that 90 per cent, about 70 per cent is referred to as ‘non specific low back pain’,” says Dr. Jean Gillies. “So, when you’re looking at non specific low back pain which I don’t ever diagnose it is not disc problems, spinal stenosis, lateral canal stenosis, DISH, and so on.”

Gillies is a rheumatologist and back specialist at St. Paul’s Hospital in Vancouver with a rare perspective, in no small part because she was a physiotherapist for 10 years before she did her M.D. and specialty training. Essentially, she says, non specific low back pain consists of sprained ligaments and strained muscles (a sprain is a partially torn ligament; a strain is an overstretched muscle): “When you sprain your ankle, your doctor won’t say, ‘Oh, you’ve got non specific ankle pain here.’ They say, ‘You’ve sprained the anterior fibres of the lateral ligament.’ It’s quite specific.”

Back pain isn’t that easy to pin down, though generally the source of the problem is a ligament, not a muscle. “In real terms, to sprain a muscle in the back, because it’s a big, flat plane, is very rare, unless you’ve got direct trauma,” Gillies says. “But to sprain the ligaments is very common the most common of back pain, or what we call mechanical enthesitis.”

It’s finding the affected ligament, buried under the back’s layers of muscle, that’s tricky. There are clues a doctor can elicit from a medical history, symptoms and a careful physical examination, including gentle movements to stretch individual ligaments to help determine its location. Then a specific treatment can be devised.

Unfortunately, making a specific diagnosis that way is extremely time consuming, Gillies says: “Because of the number of ligaments in the back and the complexity of the problem, the average patient takes me three hours. So, it’s not cost effective for an M.D. to see these patients. That’s the major reason why this isn’t done, because there are no short cuts.”

Hall, too, is convinced that “any back problem, however complex and puzzling, can be correctly diagnosed and treated. Any specialist can do it, given the experience, the necessary determination, and full cooperation from the patient.”

Whether the professionals agree or not, it’s best to take the long view. Contrary to most people’s belief, back problems don’t become progressively worse right into old age, Hall says. “As you move into those so called senior years from, say, age 65 onward your back stiffens up; everybody’s does, whether there has been pain or not. And once your back is less mobile, its sore spots and weaknesses become less subject to strain.”

The good news? “New mechanical back trouble is uncommon after 65.”