HEALTH / Second Opinion

ALMOST everyone has backache at some time. (The 10 per cent or so who never do, like the 10 per cent of people who never have headaches, are a mystery). Sufferers may be incapacitated for weeks by crippling pain combined with an inability to bend the lower spine. In Western countries back pain is second only to the common cold as a reason for people asking for help from their doctors: yet the medical profession is still groping in the dark for an explanation of what goes wrong and how to put things right. The doctor's examination is usually directed at finding evidence of pressure on a nerve causing unarguable signs such as altered reflexes and weakened muscles. If there are no such signs then the pain is attributed to 'lumbago' or 'acute back strain' and the treatment recommended may be total rest (old-fashioned) or exercises (the currently accepted approach).

Chiropractors and osteopaths claim that much backache is caused by small misalignments of the joints in the spine which can be corrected by manipulation, but research studies have shown that while manipulation may sometimes ease symptoms more quickly than pain-relieving drugs the final outcome is much the same. Most people with backache eventually get better, but how long this will take is still very difficult to forecast.

The hope had been that newer ways of investigating the spine would make diagnosis more precise. Certainly magnetic resonance imaging, which does not use X-rays and carries no health risks, gives beautifully clear images of the bones of the spine, the cartilage disc between them, and the spinal cord. Sadly, however, the abnormalities shown up on MRI scans have proved less helpful than had been hoped. People with severe backache may have normal scans; and people with abnormal scans may have no problems at all with their backs.

A report in the New England Journal of Medicine has shown how confusing the picture has become. Researchers in California found that just over half (52 per cent) of 98 people without back pain who volunteered for MRI scans showed a bulging disc and 27 per cent had a more severe protrusion. Only one-third had entirely normal spines.

Specialists are now very concerned that people with 'ordinary' backache will have a scan done and will be told that there is disc protrusion even though there is no evidence that it is doing any harm. This knowledge is likely to slow the normal process of recovery, says the New England Journal, adding that 'a diagnosis based on magnetic resonance imaging in the absence of clinical findings . . . could be the first step to disaster', by which they mean unnecessary surgery.

The problem is a growing one in many branches of medicine. Diagnostic tests have become so sensitive that no one is entirely 'normal', and if a careful search is made not only the spine but most internal organs will be found to vary from the medical ideal. For backache the consensus seems to be that such sophisticated tests should not be considered unless pain has persisted for six weeks or there is clear evidence of pressure on nerves. But in our time-conscious society how do doctors persuade people in pain to wait six weeks to see how things turn out?