New guidelines on how to treat back pain are published today by the National Institute for Health and Clinical Excellence. They include the recommendation to use chiropractic as one of several options. It will not surprise many people – after all, chiropractors have recently fashioned themselves as "back specialists". Still, this is a far cry from the gospel of DD Palmer, the American magnetic healer who invented chiropractic on 18 September 1895. Palmer was certainly not interested in back pain. On this day, he manipulated the spine of Harvey Lillard, allegedly curing him of his deafness. His second patient was suffering from heart disease and was also cured by spinal manipulation. Thus Palmer became convinced that he had discovered a new natural phenomenon: a life energy, which he called "the innate", flowing through our spine, which, when blocked by "subluxation" of the vertebrae, makes us ill. The only hope for a cure of any disease was therefore spinal manipulation. Today we know that Palmer's theory is wrong: the innate is a figment of chiropractic imagination.
The Nice guidelines, however, recommend "offering a course of manual therapy, including spinal manipulation". This has been seen in the context of the known benefits and the possible risks of spinal manipulation. The benefits were aptly summarised in the current Cochrane review of 39 studies, which showed "no evidence that spinal manipulation is superior to other standard treatments for acute or chronic low back pain".
The risks of spinal manipulation can be considerable. In a systematic review, I summarised the data from five prospective studies. Since then there have been more, all essentially finding the same: that about half of all patients suffer from mild to moderate adverse effects after chiropractic treatments. These would typically last only a day or two, and chiropractors therefore argue that they are negligible.
But very serious complications are also on record. Several hundred patients had major problems, including stroke or death, after spinal manipulations. Chiropractors argue that not all studies have confirmed that manipulation actually caused these events, or that they are extremely rare, or that upper spinal manipulations are not relevant for lower back manipulation. My reading of the evidence is that these complications are, in fact, very likely to be caused by manipulation, that nobody really knows for sure how frequently they happen, and that chiropractors often do manipulate the upper spine, even if the pain is located in the lower back.
The promotion of poorly substantiated claims has a long tradition in chiropractic. In 2001, a team of chiropractors published an analysis which demonstrated that "the largest professional [chiropractic] associations in Canada distribute brochures that make claims for the clinical art of chiropractic that are not currently justified by available scientific evidence".
In our book, Trick or Treatment? Alternative Medicine on Trial, Simon Singh and I were less polite about chiropractors' claims. Later, Singh, in an article published in the Guardian, questioned some of the statements on the website of the British Chiropractic Association (BCA) relating to chiropractic treatment for children suffering from asthma, ear infection, colic and other non-spinal conditions. His comments annoyed chiropractors so much that the BCA decided to sue for libel.
So, will I get sued as well? After all, I do argue that the Nice guidelines overestimate the benefit of chiropractic and underestimate its risk. I certainly hope not! The courtroom is no place to settle scientific disputes, and silencing journalists, scientists or sceptics with legal threats is, in my view, cowardly. Let us rather do what we have always done, and what generates real progress; discuss the best evidence in an open and transparent fashion so that we can all learn and improve healthcare.
