This should not be very surprising, as there is no logical, rational or scientific reason why manipulating a patient’s spine should treat, for example, allergies. Moreover, there is no evidence that a misaligned spine can cause any of these non-musculoskeletal conditions in the first place. Indeed, if spinal misalignments caused disease, then we would expect people with back pain to be more likely to suffer with other ailments, but in 1995 Donald Nansel and Mark Szlazak at the Palmer College of Chiropractic found no sign of this in the vast body of published medical literature: ‘There is not the slightest suggestion that patients suffering from severe primary mechanical low back pain, for instance, are more prone to develop higher incidences of prostate or testicular carcinoma, colitis, ovarian cysts, endometriosis, pancreatitis, appendicitis, diabetes, melitis, or any other category of regionally or segmentally related organ disease.’ In a follow-up study published two years later, the same researchers also failed to find any evidence that these diseases were more likely in ‘patients with broken necks or broken backs, or patients with entire hips or shoulders blown apart by shotgun blasts’.
Although Ernst and Canter’s review of reviews does not cover the impact of chiropractic manipulation on every non-musculoskeletal condition, it would be reasonable to conclude that chiropractors can offer nothing to help patients suffering from non-musculoskeletal conditions in general. This is partly because chiropractic therapy has failed whenever it has been tested as a treatment for specific non musculoskeletal conditions, and it is partly because — and this is worth stressing again — there is no reason why spinal manipulation should help with conditions ranging from ear infections to irritable bowel syndrome.
This might seem obvious, but several surveys suggest that between 11 per cent and 19 per cent of American chiropractic patients suffer from non-musculoskeletal conditions. These patients are attracted to these pointless treatments by practitioners who are willing to offer them. According to one survey, 90 per cent of American chiropractors think that the therapy should not be limited to musculoskeletal conditions, and another survey suggests that 78 per cent of Canadian chiropractors share this opinion — this indicates that the majority of North American chiropractors have straight tendencies. The percentages in Europe may be similar, particularly as supposedly responsible chiropractic bodies in European countries offer misleading information about the power of chiropractic therapy. For example, the General Chiropractic Council, which oversees chiropractic therapy in Britain, publishes a leaflet entitled ‘What can I expect when I see a chiropractor?’, which states that chiropractic therapy can lead to an improvement in ‘some types of asthma, headaches, including migraine, and infant colic’. Yet it is well known that the evidence from trials fails to support these claims.
Some words of caution for patients
In short, the scientific evidence suggests that it is only worth seeing a chiropractor if you have a back problem. However, it is still important to be cautious. In particular, we will offer six pieces of advice that should be useful for anybody considering a visit to a chiropractor:
Make sure that your chiropractor is a mixer and not a straight. It would be unwise to be treated by a chiropractic fundamentalist, namely someone who believes in subluxations, innate intelligence and the ability of spinal manipulation to cure all diseases. The terms ‘straight’ and ‘mixer’ do not generally appear on a chiropractor’s business card, so the best way to identify a straight is to ask about the range of conditions that he or she claims to treat — a straight chiropractor will offer treatments for respiratory conditions, digestive disorders, menstrual problems, ear infections, pregnancy-related conditions, infectious and parasitic conditions, dermatological diseases, acute urinary conditions and many other ailments.