Daniel David Palmer, creator of the nebulous subluxation and father of chiropractic.

Daniel David Palmer, creator of the nebulous subluxation and father of chiropractic.

When patients ask me if a chiropractor can help them with their problem, I often think to myself, “OK, do I give them the short answer or the long answer?” The difficulty is often in the fact that chiropractic is a diverse profession and it is difficult to even characterize what a “typical” chiropractor is likely to do. As a chiropractor once admitted to me – there are a great many things that happen under the umbrella of “chiropractic.”

In this article I will summarize some of the history and practice of chiropractic, highlighting what I consider to be many of the enduring problems with this profession.

The history of chiropractic

Chiropractic was founded in 1895 by Daniel David Palmer, a grocer with an intense interest in metaphysics. Prior to his “discovery” of chiropractic, D.D. Palmer was a magnetic healer. He also had interests in phrenology (diagnosing disease based on the bumps of the skull) and spiritualism. Palmer reported to have discovered the principle of chiropractic when he allegedly cured a janitor of his deafness by manipulating his neck. The fact that the nerve which conveys sound information from the ears to the brain does not pass through the neck did not seem to bother Palmer, if he was even aware of this fact.

Palmer created the term “chiropractic,” which literally means “done by hand,” to refer to his new therapy. He argued that all disease is caused by subluxated bones, which 95% of the time are spinal bones, and which disrupt the flow of innate intelligence. He did not subject his ideas to any form of research, but rather went directly to treating patients and to teaching his principles to the first generation of chiropractors.

Subluxation theory

Palmer believed in the pre-scientific vitalistic notion that health stems from the flow of a spiritual life force. Although vitalism was rapidly declining within scientific thought by the end of the 19th century, it was the centerpiece of early philosophies of health in most cultures. Palmer borrowed this ancient belief and renamed it “innate intelligence” which he claimed flowed from the brain to the rest of the body through the spinal cord and peripheral nerves. All disease, he argued, results from disruption in the flow of innate intelligence. Disruption in flow is caused by spinal subluxations, which are small misalignments in the spine that compress the spinal nerves.

Therefore, liver disease is caused by a subluxation which compresses the spinal nerve which supplies the liver with life force, depriving it of its vital innate intelligence. Palmer therefore believed he could cure by fixing these misalignments with manipulation.

This idea has remained the cornerstone of chiropractic despite advances in neurobiology and anatomy which have failed to show any evidence for innate intelligence or chiropractic subluxations. Many continue to ascribe all disease to the blockage of innate intelligence despite scientific advances in medicine which have discovered infectious, genetic, autoimmune, degenerative, nutritional, and other causes for many of the diseases which plague mankind.

Chiropractic was also not the only tradition based upon manipulating the bones. Of note, osteopathic doctors also developed an art of bone manipulation in order to heal, but they believed they were unblocking blood flow through arteries. Osteopathy and chiropractic had similar roots, but took very different paths, as we will see.

D.D. Palmer’s son, B.J. Palmer, became involved in the chiropractic movement early on, during the formative years. B.J. shared his father’s metaphysical bent (prior to chiropractic, he worked with a mesmerist and worked in the circus), his tendency to make sweeping statements about health without justification, and his ignorance of contemporary scientific knowledge. He was reported to state, for example, “When I saw there was no use for a sympathetic nervous system, I threw it out, and then just had to put something better in its place, so I discovered Direct Mental Impulse.” B.J. also “discovered” a non-existent “Duct of Palmer” connecting the spleen to the stomach. In 1907 B.J. engineered a hostile takeover of his father’s school of chiropractic.

B.J. Palmer set the tone that would later dominate the field of chiropractic. He emphasized salesmanship, advertising, and practice building. He was highly critical of medicine, stating that M.D. stands for “more death.” He continuously sought new methods for increasing revenues, such as his neurocalometer, which would pinpoint subluxations by measuring skin temperature and he decreed must be rented from him by other practitioners at exorbitant fees.

From the beginning chiropractors were also politically aggressive. They sought licensure as a protection from the growing scientific medicine with which they were completely at odds. Many legislators were reluctant to license chiropractors for this reason, but as more and more states voted in licensure, it became increasingly difficult to fight. Additionally, many legislators looked upon licensure as way of controlling the scope of chiropractic. By 1925, 32 states had instituted licenses for chiropractors. The struggle ended in 1974 when Louisiana instituted licensing.

Many states then began to pass basic science board requirements for licensure, making chiropractors pass the same tests of basic science knowledge as medical and osteopathic students. This was justified by the fact that chiropractors were presenting themselves as primary practitioners. However, where roughly 86 percent of medical students passed their basic science boards between 1927 and 1953, only 23 percent of chiropractors did. Chiropractors who could not pass the boards either moved to another state without the requirement, or practiced without a license. Between 1967 and 1979 all of the basic science laws for chiropractors were repealed.

Over the years chiropractic has never ceased its tireless struggle for growth and acceptance. Despite the fact that scientific medicine has continued to progress and chiropractic has never shed its pseudoscientific origins, they have been quite successful. After licensure, they gained coverage under Medicare. They have also successfully sued the AMA to stop their antichiropractic campaign. Today they continue to lobby hard for increased coverage and access under health insurance and HMO policies.

Straights, mixers, and reformers

Almost since the beginning, chiropractic has been fraught with many internal schisms. Today there is a wide range of differences between individual chiropractors, but most can be placed within one of three basic types.

Straight chiropractors consider themselves the only true or pure chiropractors because they limit their practice to the identification and treatment of spinal subluxations. They adhere strictly to Palmer’s concept of disease and believe that all ailments can be treated through manipulation to restore the flow of innate intelligence. Once freely flowing, they believe innate intelligence has unlimited power to naturally heal the body.

Straight chiropractors are the most extreme in their anti-scientific views. They openly advocate a philosophical rather than a scientific basis for health care, calling mainstream medicine “mechanistic” and “allopathic.” They call physicians “drug pushers” and disparage the use of surgery. They are careful not to give diseases names, but none-the-less they claim to cure disease with their adjustments. They oppose vaccinations. They also openly advocate the replacement of scientific medicine with chiropractic as primary health care. The statements of Dr. Wilson A. Morgan (who just passed away earlier this month), previous Executive Officer of Life College School of Chiropractic, are typical:

Chiropractic: The health care system whose time as the official guardian of the public’s health is fast approaching!
On the other hand, it is equally appropriate for chiropractors to be viewed as generalists in that the far-reaching effects of their highly specific spinal adjustments usually are followed by the decrease and often disappearance of a very broad array of symptoms, disabilities and pathological conditions.
Unlike the medical profession, chiropractic has a very strong philosophical basis, which no doubt has contributed to its having been labeled ‘unscientific’ by the more mechanistically-oriented scientific community.
It appears that education will prove to be the best strategy in the ‘war on drugs,’ including education about the dangers of drugs available on the street and also those available from the physician as prescriptions.

Mixers, comprising the largest segment of chiropractors, may at first seem more rational. They accept that some disease is caused by infection or other causes and they do not limit their practice to fixing subluxations. Most chiropractors in this group, however, do not supplement subluxation theory with scientific medicine, but rather with an eclectic array of pseudoscientific alternative practices. Mixers commonly prescribe homeopathic and herbal remedies, practice acupuncture and therapeutic touch, diagnose with iridology, contour analysis, and applied kinesiology, and adhere to the philosophy of naturopathy. This broad use of unproven, unscientific, and fanciful so-called “alternative” practices clearly indicates an antiscience attitude, as well as a lack of scientific knowledge, on the part of those chiropractors who employ them.

The rhetoric of mixers indicates that they are attempting to become accepted into the scientific mainstream, rather than replace scientifically based medicine with a philosophy based approach. They no longer openly oppose immunization, like straights do, but they do advocate the freedom to choose whether or not to be immunized. Their appeal to freedom is emotionally effective, especially in the United States, but it fails to recognize that immunization is far less effective in eliminating or containing infectious diseases when it is not given to everyone. They also advocate a role for chiropractors as a primary care portal of entry system within HealthCare, despite the fact that they lack adequate training as generalists skilled in medical diagnosis.

A small minority of chiropractors, numbering only about 1,000, or 2% of all chiropractors (these are rough estimates because accurate figures are lacking), have been openly critical of their own field. They have called for absolute rejection of the subluxation theory of illness, disposing of pseudoscientific and unethical practices by chiropractors, and the restriction of chiropractic to treating acute musculoskeletal symptoms. They are attempting to bring their field into the scientific mainstream.

Occasionally chiropractic reformers have attempted to forge a new profession, entirely shedding the pseudoscience attached to the chiropractic brand. About ten years ago one group in Canada renamed themselves “Orthopractors,” and considered the new discipline of orthopractic as distinct from chiropractic. Orthopractic is the use of manipulation to provide symptomatic relief from uncomplicated acute back strain. They do not believe in maintenance therapy, treating medical ailments, or the use of pseudoscientific alternative practices.

Unfortunately, this reform effort died because “orthopractic” did not exist as a legal entity. This also partly explains why the “chiropractic” label persists and covers such a wide range of philosophy and practice – because it exists as a recognized licensed profession. It has a regulatory inertia that is hard to combat.

To further complicate things, spinal manipulation exists outside of the chiropractic profession, and not all manipulation is chiropractic manipulation. Some physiatrists, sports medicine doctors, and osteopaths legitimately employ manipulative therapy to relieve muscle strain, mobilize joints, and improve function. Chiropractors do this as well. But some chiropractors also do chiropractic manipulation designed to realign the spine and reduce imaginary chiropractic subluxations.

The evidence: Subluxations

In the past 100 years, there has been very little research conducted into the basic principles of straight chiropractic. There is no research that indicates the existence of innate intelligence or that such a force plays any role in health and disease. Further, the evidence strongly suggests that chiropractic subluxations are a figment of the chiropractic imagination. And it also seems that spinal manipulation is not capable of realigning the vertebra of the spine.

A study carried out by Edmund Crelin, Ph.D. investigated the amount of force necessary to displace vertebral bones of the spine in order to cause impingement of a spinal nerve. The study was carried out on six corpses within 8 hours after death. His conclusion was that the amount of force necessary to actually displace the vertebra was great enough to break the spine, arguing strongly that chiropractic manipulation cannot significantly affect spinal alignment, and that misaligned spines do not caused pinched nerves.

Pinched or impinged spinal nerves do occur, but they are caused by herniated discs, fractures, tumors, or overgrowth of the vertebral bones. When spinal nerves are impinged they cause pain, numbness, and tingling and may cause a decrease or loss of deep tendon reflexes and weakness of the muscles supplied by the affected nerve. Impinged nerves are not caused by subluxations nor do they result in diseases of the organs. Believers in subluxation theory must claim, implausibly, that nerve impingement causes only a blockage of innate intelligence without causing any of the known signs and symptoms of such impingement.

Ironically, spinal manipulation is contraindicated in cases of actual nerve impingement and should not be performed. In medical studies of manipulation, such as the RAND study, often cited by chiropractors as evidence for manipulation, spinal nerve impingement was considered a reason not to have manipulation and therefore was a criterion for exclusion from the study.

Another source of evidence that the chiropractic theory of subluxations and innate intelligence is completely false comes from the unfortunate victims of spinal trauma. There are many victims of complete transection, or disruption, of the cervical spinal cord in the neck. Such a complete injury leaves its victim quadraplegic, unable to move the arms or legs. If the injury is high enough in the spinal cord the victim may not even be able to breath on their own. In such victims no impulses from the brain are able to travel below the spinal cord in the neck, and therefore most of the communication between the brain and the body is interrupted. Certainly, this is a much more dramatic and complete interference of nerve flow than that of an impinged spinal nerve.

Yet, in these patients, the organs continue to work without difficulty and diseases do not develop at any higher rate than those without such an injury. Of course, there are some effects from the disruption of the autonomic nervous system, that part of the nervous system which regulates the bladder, the degree of bowel motility, and other functions. But all effects of spinal cord damage are caused by known neurological injury. If subluxation theory were correct, then patients with high spinal cord injuries would be ravaged by every conceivable disease.

So chiropractors cannot realign the spine to fix imaginary subluxations and restore the flow of nonexistent innate intelligence. Subluxation theory is pure pseudoscience, like homeopathy or therapeutic touch, and has no place in a 21st century scientific health care system.

Despite the extreme scientific implausibility of subluxation theory, specific applications have been tested with clinical research – with predictable results. For example, many chiropractors will use manipulation to treat asthma is children. The results of this research are soundly negative – chiropractic does not work on asthma.

Despite this many chiropractors persist in treating asthma. This led Simon Singh to write in The Guardian in 2008 that the British Chiropractic Association, which does advocate chiropractic for childhood asthma, “promotes bogus therapies.” In response to this statement the BCA notably did not provide the evidence that Singh claimed was missing. Rather, they sued him for libel (the case is ongoing).

Next week I will cover the evidence for musculoskeletal uses of chiropractic.





  • Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also has produced two courses with The Great Courses, and published a book on critical thinking - also called The Skeptics Guide to the Universe.

Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also has produced two courses with The Great Courses, and published a book on critical thinking - also called The Skeptics Guide to the Universe.