Chiropractic has come a long way since its invention in 1895, but where is it going? Its inventor, Daniel David Palmer, was a grocer and magnetic healer who didn’t have the benefit of x-rays and didn’t know about the germ theory of disease. Based on pseudoscientific and metaphysical ideas, chiropractic has been trying to establish scientific respectability for well over a century but has failed. The evidence for its safety and effectiveness remains questionable, yet it has developed into perhaps the most widely accepted form of alternative medicine, and new chiropractic offices are popping up everywhere. Critics have called for it to be abolished, and some chiropractors say they are trying to reform it from within. What will the future bring?
Anyone can try to predict the future, but predictions are notoriously fallible. I think it is safe to predict that complementary and alternative medicine (CAM) will always be with us, as long as humans display human nature. After all, homeopathy is still thriving despite being thoroughly discredited by Oliver Wendell Holmes as early as 1842, despite being tested and proven not to work, and despite being totally incompatible with well-established scientific knowledge. So I expect chiropractic to persist. But in what form? There are many possible paths that chiropractic might follow. Will it still be as widespread a century from now; and if so, what will it look like?
D.D. Palmer believed that all body functions were controlled by a vitalistic spirit he called Innate. He proclaimed that spinal subluxations caused 95% of all disease by interfering with Innate, and that subluxations of other bones caused the remaining 5%. He said his inspiration for chiropractic was received from “the other world” and it was bolstered by his belief that he had restored a deaf janitor’s hearing by adjusting his spine. He was wrong on all counts.
Chiropractic was soon divided into two camps. The “straights” are purists who follow D.D. Palmer’s original ideas and limit themselves to correcting subluxations. The “mixers” are open to other ideas and have adopted conventional techniques from physical therapy such as exercise, massage, ultrasound, and moist heat. Some mixers adopt techniques from alternative medicine such as nutritional supplements, acupuncture, homeopathy, and herbal remedies. And today we have other variations like craniosacral therapy and upper cervical chiropractic (which claims to correct everything downstream by adjusting the top vertebra in the neck).
The subluxation myth
The concept of subluxation underlies chiropractic theory. Medical subluxations are real. They are partial dislocations of a joint and are readily seen on x-ray. Originally chiropractors thought they were correcting “chiropractic subluxations” that were actual bones out of place (BOOP); they assumed they would be obvious on x-ray and they convinced themselves they could identify them on x-rays. But two chiropractors would identify subluxations at different levels on the same x-ray. They couldn’t agree, and they had to admit that the bones were not really out of place; so they had to develop a new definition of subluxation.
The World Health Organization (WHO) defines the chiropractic vertebral subluxation as “A lesion or dysfunction in a joint or motion segment in which alignment, movement integrity and/or physiological function are altered, although contact between joint surfaces remains intact. It is essentially a functional entity, which may influence biomechanical and neural integrity.” And the National Board of Chiropractic Examiners stated in 2014, “The specific focus of chiropractic practice is known as the chiropractic subluxation or joint dysfunction. A subluxation is a health concern that manifests in the skeletal joints, and, through complex anatomical and physiological relationships, affects the nervous system and may lead to reduced function, disability or illness.” And other organizations have come up with other equally vague definitions. Real medical illnesses are usually much better defined. Anyone can diagnose diabetes on the basis of blood sugar measurements or anemia on the basis of hemoglobin levels in the blood. But you would have to be a chiropractor to use these definitions of subluxation to diagnose a subluxation. They amount to gobbledygook designed to provide an excuse for chiropractors to “adjust” the spine of any patient they want to treat.
Eventually even some chiropractors came to question the existence of the chiropractic subluxation. In 2005, a group of chiropractic researchers reviewed all the published scientific evidence. They concluded, “No supportive evidence is found for the chiropractic subluxation being associated with any disease process or of creating suboptimal health conditions requiring intervention. Regardless of popular appeal this leaves the subluxation construct in the realm of unsupported speculation. This lack of supportive evidence suggests the subluxation construct has no valid clinical applicability.”
In an ideal, rational world, perhaps this would have been the death knell of chiropractic; but of course, it wasn’t. There are too many chiropractors whose livelihood depends on it, and patients have been trained to expect their chiropractor to find a misalignment of the spine and correct it. And there are regulatory constraints: the word subluxation is enshrined in legislation for Medicare reimbursement and in health insurance company policy. Chiropractic has become so widely accepted that even the government is hiring; chiropractic clinics have been established in VA and military medical facilities.
Spinal manipulation therapy
Chiropractic’s main claim to fame is spinal manipulation therapy (SMT). But SMT is not uniquely chiropractic; it is also used by physical therapists, Doctors of Osteopathic Medicine (DO’s), and some medical doctors (physiatrists, physical medicine and rehabilitation specialists). SMT is somewhat effective for low back pain, but it is not more effective than other standard treatments such as analgesics, physical therapy care, exercises, and back school. So it is a reasonable choice, but can’t be recommended as the superior treatment of choice.
For neck pain, SMT combined with exercise has been shown to benefit some patients, but manipulating the neck carries a risk of stroke, paralysis, and even death from a tear in a neck artery. Chiropractors deny the risk, and it is certainly very small, but there is credible evidence including “smoking gun” cases where the patient suddenly developed symptoms of an arterial dissection on the chiropractor’s table during neck manipulation. Gentle mobilization can be effective and is much less likely to cause a stroke.
Claims that SMT benefits conditions other than low back pain and neck pain are not supported by scientific evidence. It is not effective for asthma, infant colic, ear infections, sleep and feeding problems, health maintenance, or indeed for any non-musculoskeletal condition.
Chiropractors treat children whose spines have not yet fully developed. They sometimes treat infants immediately after birth, in the delivery room. There is no accepted indication for offering chiropractic treatments to young children, and many experts consider it a form of child abuse.
Osteopathic medicine developed around the same time as chiropractic, but it evolved very differently. It was also based on spinal manipulation therapy; but unlike chiropractors, doctors of osteopathic medicine (DO’s) have accepted modern scientific medicine. They have joined the mainstream and are considered equivalent to MD’s. Schools of osteopathy teach SMT, but DO’s take the same residencies and specialty training and have to pass the same exams as MD’s, and many of them seldom use SMT after graduation.
Chiropractors who go beyond chiropractic
Since chiropractic is not a science-based practice, many chiropractors’ education has not prepared them to understand science. The research published in chiropractic journals tends to be of low quality. And many chiropractors show poor judgment in gullibly adopting every new quackery that comes along, such as spinal decompression machines, electrodermal diagnostic machines, and untested stem cell treatments. A large percentage of American chiropractors use applied kinesiology, a bogus muscle-testing procedure. A long list of questionable diagnostic and treatment practices used by chiropractors is available on the Chirobase website at https://www.chirobase.org
Chiropractors have tried to expand their scope of practice. Some have set themselves up as allergy specialists, using the bogus Nambudripad Allergy Elimination Technique (NAET) devised by a chiropractor who is also an acupuncturist. Some run clinics to treat diabetes, even claiming to “reverse” diabetes. Some offer advice on nutrition and all aspects of wellness. Some have tried to re-brand themselves as primary care physicians, a role their training does not equip them to fill. Some want to do sports physicals and act as team physicians.
It seems to me all this amounts to a tacit admission that they have realized chiropractic is inadequate.
Can chiropractic be reformed?
Some chiropractors are trying to reform. They are doing their best to follow scientific principles. They reject the subluxation concept and limit their practice to short-term evidence-based treatment of selected musculoskeletal problems. They would like to make us think there is a reform movement underway, but I haven’t seen any indication that chiropractic as a whole is trying to follow their lead. From reviewing chiropractic websites, it seems that most chiropractors are firmly ensconced in the old ways and embrace one or more quack methods.
If they were serious about reform, chiropractic organizations could start by disciplining any of their members who treat young children, who claim to be correcting subluxations, who use applied kinesiology, or who fail to support immunizations. There have been some promising developments in Australia: for instance, the Chiropractic Board of Australia has advised chiropractors not to use spinal manipulation under the age of two pending an independent review of the evidence. That’s a start, but there’s much more that could be done.
The problem with reforming chiropractic is that it becomes indistinguishable from what physical therapists do (except that physical therapists’ training and scope of practice are more extensive). I see no reason to prefer a reformed chiropractor to a good physical therapist who offers SMT. So why do we need chiropractors? They are often very skilled in SMT, so perhaps they could be re-trained with a new title, becoming physical therapists for the spine.
I won’t try to predict what will happen with chiropractic, but I can confidently predict that skeptics will never stop supporting science and critical thinking.
For more information, see the Chirobase website operated by Quackwatch’s Dr. Stephen Barrett and skeptical chiropractor Samuel Homola https://www.chirobase.org and my video lecture on chiropractic on YouTube at https://www.youtube.com/watch?v=MO84J8xtOxI
This article was originally published in Skeptical Inquirer as a Reality Is the Best Medicine column.