Trick or Treatment—The Undeniable Facts about Alternative Medicine (Electronic book text)

If you have never visited a chiropractor, then the easiest way to imagine spinal manipulation is by analogy to an experiment you can do with your hand. Position your right forearm vertically upwards and hold your right hand flat, with the palm facing up — as if you are carrying a tray of drinks. Your wrist should be able to bend backwards so far that your flat hand begins to dip slightly below the horizontal — this is what we have called level-one flexibility. If you use your left hand to press steadily and firmly downwards on your right palm, then the wrist can be bent a little further down by a few degrees, which is level-two flexibility. Imagine — and please do not do this — that your left hand applied an additional short rapid thrust on your right hand, thus bending it down even further by a small amount. This would be level-three flexibility, akin to the sort of action involved in spinal manipulation via a high-velocity, low-amplitude thrust.

Because spinal manipulation is the technique that generally distinguishes chiropractors from other health professionals, it has been at the centre of efforts to establish the medical value of chiropractic therapy. Researchers have conducted dozens of clinical trials in order to evaluate spinal manipulation, but they have tended to generate conflicting results and have often been poorly designed. Fortunately, as with acupuncture and homeopathy, there have been several systematic reviews of these trials, in which experts have attempted to set aside the poor trials, focus on the best-quality trials and establish an overall conclusion that is reliable.

In fact, there have been so many systematic reviews that in 2006 Edzard Ernst and Peter Canter at Exeter University decided to take all of the current ones into account in order to arrive at the most up-to-date and accurate evaluation of chiropractic therapy. Published in the Journal of the Royal Society of Medicine, their paper was entitled ‘A systematic review of systematic reviews of spinal manipulation’. Ernst and Canter’s review of recent reviews covered spinal manipulation in the context of a large range of conditions, but for the time being we will concentrate on the most common problems dealt with by chiropractors, namely back and neck pain. In this context they took into account three reviews looking at back pain alone, two reviews looking at neck pain alone and one review that covered both neck and back pain.

The individual reviews came to varying conclusions. In the case of neck pain, two reviews concluded that spinal manipulation was ineffective, although one of them did find some evidence that chiropractic manipulation could be effective when used in combination with standard treatments. However, the combination effect is hard to dis-entangle, so it would be difficult to draw anything significant from this. The third review was more positive, concluding that spinal manipulation offered patients a moderate benefit, but it is worth noting that the lead author on this review was a chiropractor. Ernst and Canter had previously shown that chiropractors tend to generate more optimistic conclusions than scientists, perhaps because they have an emotional investment in the result. All in all, the evidence was insubstantial.

For back pain, there was more of a consensus that spinal manipulation could be effective. Each review suggested that, on average, patients received benefit from the sort of treatments offered by chiropractors, but there was disagreement over the extent of that benefit and the evidence was not conclusive. The fact that chiropractic spinal manipulation might help with back pain is not a major milestone in the history of medicine — but it is particularly noteworthy in the context of this book, because this is the most significant evidence so far that an alternative treatment might genuinely help patients.

On the other hand, this conclusion should not be interpreted as an endorsement of chiropractors or a recommendation that patients with back pain should try spinal manipulation. The key question is not merely ‘does spinal manipulation work?’, but rather ‘does spinal manipulation work better than other forms of treatment?’

Dealing with back problems is notoriously difficult, and conventional medicine has struggled to develop truly effective treatments. In terms of dealing with the underlying problem, doctors might recommend physiotherapy or exercise. And in terms of dealing with the symptoms, doctors often prescribe non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. These approaches are, however, only mildly or marginally effective. A truly life-changing cure for back pain has not yet been found.