By treating back pain as a disease on its own, medicine has gone down many blind alleys. But many cases of back pain are only symptoms of disorders in other areas of the body including heart disease.
In the body, no area presents more of a problem to doctors than the back. Second only to head pain, disabling low back pain strikes 80 per cent of us during our lifetimes, causes millions of lost work days and accounts for a steady stream of presentations to general practitioners.
In spite of endless research into its diagnosis, causes and treatment, our doctors seem no nearer to understanding back pain than they ever were. Today, misdiagnosis or unproven and aggressive treatment with drugs and surgery contributes more to the problems of back pain sufferers than they do to the solutions.
Nearly 10 years ago, Prof Gordon Waddell, author of The Back Pain Revolution (Churchill Livingstone, 1998) and orthopaedic surgeon at Glasgow's Western Infirmary (and one of the experts who helped to draft the present Royal College of General Practitioners' guidelines for the treatment of back pain), noted that dramatic surgical successes were rare, applying to only 1 per cent of patients with low back (lumbar) disorders. "Our failure," he wrote, "is in the 99 per cent of patients with simple backache, for whom, despite new investigations and all our treatments,
the problem has become progressively worse (J Weinstein, S Wiesel, eds, The Lumbar Spine, Philadelphia: WB Sanders & Co, 1990)."
Chronic low back pain continues to be common, expensive and difficult to manage by conventional medical and surgical treatment (N Eng J Med, 1988; 318: 291; Clin J Pain, 1997; 13: 91-103; J Am Acad Orthop Surg, 1994; 2: 157-63).
Traditional methods of diagnosis are still very ineffective. For instance, routine x-rays to determine whether low back pain is caused by a serious condition are virtually useless. A recent study from Canada looked at whether routine lumbar radiography was both cost efficient and effective in detecting serious problems, like cancer, which could lead to low back pain.
Of the 963 patients participating, only 13 per cent of patients were referred for x-rays, of which only 5 per cent (less than 1 per cent of the 963 patients) showed degenerative changes in the back. Only one patient showed evidence of malignancy.
On the basis of these findings, the authors concluded that in the 20 to 50 year old group, the likelihood of finding a malignancy, for instance, was 1 in 2500. The likelihood of finding any disease which requires specific therapy was less than 0.2 per cent (J Am Med Assoc, 1997; 277: 1782-6).
Tracking down the cause
By treating back pain as a disease rather than a symptom, we have gone down many blind alleys of diagnosis and treatment, with many patients only suffering increased pain from inappropriate treatment.
Some doctors have suggested that conventional medicine can increase its understanding of the back and its problems by adopting a chiropractic/osteopathic understanding of back pain (Br J Gen Pract, 1997; 47: 653-5). The back then becomes part of a whole, complex structure that includes the spine, hips, pelvis, ribs and their surrounding muscles and ligaments and other supporting tissues, as well as the organs contained within those bony structures. Dysfunction or displacement of any of these parts of the structure can eventually lead to backache.
Like head pain, back pain can take many forms and has many causes: gynaecological, rheumatic, infectious or vascular. Although a large proportion of back pain appears to come on spontaneously, often it's the result of insults and traumas to the body over a period of months or years. Occasionally, the pain is caused by functional problems: slipped, ruptured or herniated discs, pinched or otherwise compromised nerve roots, or fused or deteriorating vertebrae. For a significant number, the cause of back pain is never found.
Backache may occasionally involve organs not thought to be directly related to the neck and spine. For instance, low back pain can be caused by a duodenal ulcer (Arch Phys Med Rehabil, 1998; 79: 1137-9), or acute pancreatitis (J Can Chirop Assoc, 1992; 36: 75-83).
Back pain can also be linked to heart problems. The biggest study in this area was undertaken by a group of Finnish researchers. For 13 years, they followed 8,816 Finnish farmers via a postal study. The group comprised 3,842 women and 3,648 men aged 30 to 66 with no previous history of heart problems. Men who had reported back pain, including sciatica, before they took part in the study had a significantly increased risk of dying of ischaemic heart disease during the 13 year follow up. The association remained even after adjusting for age, smoking habits, body mass index and social status (BMJ, 1994; 309: 1267-8).
The link between heart and back isn't so farfetched. The muscles in the back have a vital role to play in helping to pump the blood back into the heart. As they contract, they squeeze blood out of the surrounding tissues. In a back which has been injured, for example, the muscles may stay in a continuous state of spasm even without symptoms. Unable to pump efficiently over a period of years, this damage can build up and adversely affect heart function (see Dr P Sherwood, The Heart Revolution, Arrow, 1994).
The connection between the heart and the back, however, runs both ways. There is some evidence, for instance, that a poorly functioning vascular system is linked to chronic back pain. If the large veins that supply blood and nutrients to the spinal column and related joints are not functioning properly, degeneration can occur. Poor blood supply to the muscles in the lower back may also contribute
(J Spinal Disord, 1999; 12: 162-7; Ann Rheum Dis, 1997; 56: 591-5).
Muscles elsewhere that are either poorly toned or hyper-toned may also be a contributing factor.For instance, abdominal muscles are known to play a part in maintaining back health. In a small Australian study, those with lower back pain were the least able to contract their abdominal muscles effectively. The authors suggested that this type of neuromuscular dysfunction may have a role to play in back pain (Aust J Physiother, 1997; 43: 91-8). When back muscles are weak, a series of back exercises has also been shown to be effective in relieving backache (Spine, 1990; 15: 120-3; 1995; 20: 469-72).
Tight, shortened hamstrings are also a contributory factor. In one study, men with low back pain had greater stiffness in the hamstrings and lower trunk flexibility than the control group, who did not have back pain (Clin Biomech, 1996; 1: 16-24).
In too many instances, backache is the sad result of medical meddling. Research shows that surgery causes more pain than it cures (WDDTY, 1993, vol 4 no 8). In fact, patients with chronic back pain often find that their symptoms improve when they're taken off drugs
(J Musculoskel Med, 1990; 7: 17; Spine, 1980; 5: 356).
Many women who have given birth under epidural anaesthesia know only too well the long term cost of meddling with short term, self limiting pain. Although vehemently disputed by anaesthetists (BMJ, 1997; 314: 1062-3), the accumulated evidence suggests that the link between back pain and epidurals cannot be ignored. When the data of the four main studies into obstetric epidural and backache (BMJ, 1995; 311: 1336-9; BMJ, 1990; 301: 9-12; BMJ, 1993; 306: 1299-303; Anaesthesiology, 1994; 81: 29-34) are combined even taking into account that the different authors reached different conclusions the fact emerges that 1 in 12 women who have epidurals are likely to suffer long term back pain (BMJ, 1996; 312: 581).
Cures that work
The relatively new notion in medicine of treating the back holistically was summed up in an editorial in the British Medical Journal (1996; 313: 1343-4), written in response to the most recent guidelines on back pain issued by the Royal College of General Practitioners (Clinical guidelines for the management of acute low back pain, London: RCGP, 1996). "The era of routine radiography, strict bed rest, corsets, and traction has passed," it said, ". . . replaced by parsimonious imaging, early return to normal activities, and a greater emphasis on exercise to prevent recurrences or to treat chronic pain."
Publishing new guidelines, of course, doesn't guarantee that individual doctors will take them up. In a recent study of 251 UK general practices, the availability of only one of eight recommended services for back pain sufferers had improved, and then only slightly. Physical therapy (encompassing physiotherapy, osteopathy and chiropractic) was more often available in fundholding practices (which have more influence over purchasing decisions) than non fundholding practices (BMJ, 1999; 318: 919-20).
Another study showed that when funding for such services was made available, GPs did make good use of them and their back pain patients benefited they took less drugs, had fewer certified sick days and made fewer trips to the GP (J Manip Physio Ther, 1998; 21: 14-8).
High on the list of the most effective cures are the physical therapies (J Manip Physio Ther, 1999; 22: 87-90). Unfortunately, guidelines for the referral of patients to physical therapy or spinal manipulation do not differentiate between chiropractic, osteopathy and physical therapy. This lack of a precise, common language may be at the root of continuing disagreements over which type of physical therapy is best for which type of backache. Medical research has not helped to clarify the issue; indeed, researchers may deliberately misuse terms such as "chiropractic" in their research.
In one important paper, the ways in which bias creeps into back pain research were highlighted (J Manip Physiol Ther, 1995; 18: 203-10). In a study of papers on adverse effects of spinal manipulation, the researchers found that when there was an adverse effect, it was more often attributed to "chiropractic" (often regardless of whether the original paper cited chiropractic involvement). When there was no adverse effect, the therapy was usually referred to as "spinal manipulation". As the authors note, "In many cases, this is not accidental; the authors had access to original reports that identified the practitioner involved as a non chiropractor."
Another problem is the quality of the studies. One review of randomised, controlled trials from 1966 to 1995 concluded that the studies of chiropractic are of "uneven quality" (Alt Ther Health Med, 1997; 3: 111-2). Another, often quoted review of 36 randomised clinical trials comparing spinal manipulation to other treatments concluded that out of a possible 100 points (indicating the highest quality studies), the highest score achieved by studies of spinal manipulation was 60 (Spine, 1996; 21: 2860-71). Nevertheless, the review showed a significant number of positive results for spinal manipulation, which clearly justified more and better research into the field.
One trial, however, did seek to compare chiropractic directly with conventional outpatient treatment. In what was considered a high quality trial, authors TW Meade and his colleagues examined the study group twice and found good evidence for the use of chiropractic over the longer term (BMJ, 1990, 300: 1431-7; BMJ, 1995; 311: 349-51) . Other reviews have demonstrated the effectiveness of manipulative therapy in the treatment of back pain (Clin Invest Med, 1992; 15: 527-35), at least for short term pain relief.
More treatment options
Pain is both a physical and psychological event. Research suggests a link between psychological unease and back pain (Psychosomatics, 1991; 32: 309-16). Factors such as stress may cause pain by increasing local muscle tension, which eventually becomes painful because of the accumulation of waste products in the muscle (Pain Mgmt, 1991; 4: 24-7; Am Pain Soc J, 1994; 3: 119-27).
Some conventional practitioners now recommend that techniques such as meditation, hypnosis, biofeedback and cognitive behavioural therapy be integrated into back pain management (Spine, 1996; 21: 2851-9). This view has recently been upheld by America's National Institutes of Health (NIH Technology Assessment Conference Statement, Bethesda, MD: NIH, 16-17 Oct 1995).
In one very small study, such techniques, reinforced through group support, resulted in lower stress levels, a decrease in pain of 47 per cent, a decrease in visits to the doctor of 37 per cent and a rise in the ability to cope with pain by 73 per cent. Physical activity among group members also increased on average 47 per cent (J South Orthop Assoc, 1998; 7: 81-5).
Doctors also need to address the question of whether some back pain is self limiting. Certainly one major study concluded that it is; for more than 90 per cent of patients, the problem will usually resolve itself within six weeks, whatever the treatment in this case either primary care from a GP or chiropractic (N Eng J Med, 1995; 333: 913-7).
However, a smaller study from Manchester suggests that caution is needed when interpreting such findings. While most back pain sufferers did indeed stop going to their doctors within three months, back pain
and related disability continued to be a feature in their lives (BMJ, 1998; 316: 1356-9).
Only 25 per cent of the patients who consulted about low back pain had fully recovered 12 months later. Clearly, it was not the pain but their faith in their doctors' ability to do anything about it which had changed.
The difference may be due to the length of the studies. While short term follow up suggests that back pain is self limiting, long term follow up shows that back pain runs a recurrent course, characterised by variation and change (Spine, 1996; 21: 2833-7). There may also be significant variations in the study groups. Those suffering from long term backache are often the most difficult to cure. But when back pain comes on suddenly for no discernible reason, it may well be self limiting, and the best initial treatment may be no treatment at all.
When French doctors looked at a group of 103 patients with sudden, unexplained backache and no previous history of back problems, some 90 per cent of them recovered within two weeks a much higher recovery rate than in other studies. During the three month course of the study, there was a decrease in pain every day (BMJ, 1994; 308: 577-80).
Finnish researchers have come to much the same conclusion.When they compared three treatment options bed rest, back exercises or ordinary activity it was ordinary activity, within the limits permitted by the pain, which led to a more rapid recovery, suggesting that general mobilisation may be as useful as joint mobilisation
(N Eng J Med, 1995; 332: 351-5).