I am often asked, “What do chiropractors do?” That’s not an easy question to answer. The answer is usually expected to be, “They treat back trouble.” But as alternative medicine practitioners, chiropractors do a lot of things, and they treat a variety of ailments, based largely on a scientifically-invalid vertebral subluxation theory which proposes that nerve interference resulting from a misaligned vertebra or a dysfunctional spinal segment can affect general health.

As a co-host of the Chirobase web site, I frequently answer questions about chiropractic, some of which are published in a section titled “Consumer Strategy/Consumer Protection.” In this post, I’ll focus on these:

  • Are Subluxations Causing My Health Problems?
  • Is a Misaligned Atlas Causing My Back Pain?
  • What is that “Thumper” My Chiropractor Uses on My Back?
  • How Does a Chiropractor Locate Subluxations?
  • Should I Let a Chiropractor Adjust My Baby?
  • Why Is Every Chiropractor’s Treatment Different?
  • Can Neck Manipulation Cause a Stroke?
  • Should I Go to a Chiropractic College?
  • Are There Any Good Chiropractors?
  • Is It Possible to Reform the Chiropractic Profession?

By far, most of the questions I receive express concern about questionable methods and advice offered in the offices of chiropractors. Many questions are generated by the suspicions of patients who initially visited a chiropractor for treatment of back pain and who were then offered spinal adjustments as a treatment for health problems unrelated to the spine. Patients are often concerned about the expense involved in such care, usually extended over a long period of time, followed by “maintenance care” to correct or prevent “vertebral subluxations” after symptoms have resolved. I generally advise patients to refuse chiropractic care for anything other than a musculoskeletal problem, to seek treatment only when symptoms are present, never pay for treatment in advance, and to discontinue treatment and see an orthopedic specialist if symptoms worsen after a few days or have not subsided after a week or so.

Are subluxations causing my health problems?

No. Unfortunately, the chiropractic vertebral subluxation theory sounds plausible to medically untrained persons. When a chiropractor explains the subluxation theory, holding up a real spine and then pointing to a nerve chart showing spinal nerves connecting with all the body’s organs, along with a list of diseases caused by “nerve interference,” few lay persons are knowledgeable enough to question the theory. The truth is that spinal nerves supply musculoskeletal structures. The body’s organs are supplied by ganglia (some of which receive preganglionic fibers from the thoracolumbar portion of the spine) and plexuses in a separate autonomic nervous system located outside the spinal column and by the all-important vagus (cranial) nerves which pass down from openings in the base of the skull to supply thoracic and abdominal organs. Hearing, sight, and other functions involving structures in the head are supplied by cranial nerves which pass through openings in the skull. Autonomic fibers supplying pelvic viscera pass through solid bony openings in the sacrum at the bottom of the spine. Obviously, the well-protected autonomic nervous system, so essential to life, is not threatened by a vertebral subluxation.

A spinal nerve is rarely compressed by a misaligned vertebra. When a spinal nerve is compressed, usually by disc herniation or osteophyte formation, symptoms occur in the musculoskeletal structures supplied by the affected nerve but the body’s organs are not affected. Severance of the spinal cord at or above the 4th cervical vertebra, shutting off brain impulses to spinal nerves, can cause paralysis of muscles from the neck down while the body’s organs continue to function.

Although the original theory of chiropractic defines a subluxation as a vertebral misalignment that places pressure on a spinal nerve, more recent theories define a subluxation as a “vertebral subluxation complex” that affects nerve, blood vessel, and connective tissue structures in a spinal segment, causing nerve interference without misalignment of a vertebra. Both types of subluxations are alleged to affect general health; neither has been proven to exist. Nevertheless, it is common practice among chiropractors to treat a health problem by adjusting the spine to “realign the vertebrae” or to “remove nerve interference.”

Click to embiggen.

Click to embiggen.

This is a portion of an old Meric System chart that assigns certain vertebrae to certain organs and diseases; it ignores the cranial nerves which pass through openings in the skull. Some subluxation-based chiropractors still use this chart to determine which vertebrae to adjust when treating an organic problem. “Up-to-date” chiropractic upper cervical specialists, however, claim that simply adjusting the atlas to remove pressure on the brain stem will “restore perfect health” (

Is a misaligned atlas causing my back pain?

One of the most common and exasperating questions I receive comes from chiropractic patients who have been told that misalignment of the atlas, the uppermost neck vertebra, is the cause of a great variety of ailments from the neck down, including low-back pain. Frightened by scare tactics that predict dire consequences from atlas misalignment that allegedly presses on the brain stem, patients are often reluctant to discontinue treatment they have been led to believe will prevent the development of illness.

When the atlas is not locked or fixated by injury or disease and is freely movable, its resting place is dictated by the anatomical configuration of joint surfaces and cannot be changed. When the atlas is moved by manipulation, it always returns to its normal resting place. Atlas “subluxations” found in the necks of persons who are not having a neck problem are usually the result of measuring structural asymmetry and are not significant.

Patients are always relieved to hear that their atlas is not out of place and that they do not need atlas adjustments to restore or maintain their health. An atlas misalignment is certainly not a cause of low-back pain.

What is that “thumper” my chiropractor uses on my back?

An adjusting instrument using a spring-loaded stylus.

An adjusting instrument using a spring-loaded stylus.

Once a patient has been convinced that his or her spine harbors vertebral subluxations that can cause disease or affect general health, any one of dozens of chiropractic adjustive techniques might be used to correct and prevent recurrence of such subluxations. One of the most bizarre methods of adjusting the spine uses a handheld instrument with a spring-loaded or electrically powered mallet or stylus to tap on selected vertebrae. A dubious leg-length check might be used to determine if correct alignment has been restored, a procedure so implausible that it is the subject of many of the letters I have received from chiropractic patients.

Some computerized adjusting instruments use a piezoelectric sensor that will allegedly locate and correct a vertebral subluxation by analyzing the echo of an oscillating force applied to a vertebra. Such an instrument has proved to be an effective way to sell chiropractic care and is often advertised as “advanced chiropractic technology.” While some chiropractors genuinely believe that the vertebral subluxation theory is valid, subluxation-based “chiropractic technologies” have more to do with marketing than with health care.

How does a chiropractor locate subluxations?

Chiropractors generally locate subluxations by measuring x-ray images of vertebral misalignment caused by degenerative changes or structural abnormality, such as disc degeneration or spinal curvature. Such “subluxations” are usually asymptomatic and not significant. Subluxation-based chiropractors might use such “advanced technology” as computerized surface electromyography (not the same as needle electromyography used by neurologists) that prints out brightly colored charts measuring electrical activity in muscles, alleged to indicate the presence of vertebral subluxations. Some use thermography that measures an elevation in skin temperature believed to be associated with vertebral subluxations. Applied kinesiology (not the same as the science of kinesiology) is a nonsensical way of locating subluxations by testing arm strength before and after a spinal adjustment; it is also used to detect the presence of disease and vitamin deficiency. Many chiropractors claim to be able to find vertebral subluxations by palpating the spine, that is, by using fingertips to feel vertebrae.

All such subluxation-detection devices and procedures are as dubious as the subluxation theory that prompts their use.

Remember that a real orthopedic subluxation, a partial dislocation, causes musculoskeletal symptoms and is not the same as an asymptomatic chiropractic vertebral misalignment (subluxation) or an undetectable “vertebral subluxation complex” alleged to be a cause of bad health.

Should I let a chiropractor adjust my baby?

No! When I see a chiropractor palpate the spine of an infant or a neonate in a search for subluxations, I suspect either fraud or woeful ignorance. There is no way that a chiropractor can find a subluxation by palpating the fat-padded cartilaginous spine of a newborn baby. Following up such an examination with an attempt to correct vertebral alignment by manipulating the baby’s spine is unnecessary and dangerous.

There has been some speculation that manipulating the immature spine of an infant or a small child might damage the soft, cartilaginous growth centers in the vertebrae, resulting in the development of pre-adolescent spinal deformity, such as scoliosis or Scheuermann’s kyphosis (O’Neal 2003) — a speculation worth considering since there is no reason to believe that manipulating the spine of a small child is ever helpful or indicated.

Why is every chiropractor’s treatment different?

The techniques of manual generic spinal manipulation performed by science-based practitioners are pretty much the same, no matter who does the manipulation, whether done by a chiropractor, a physical therapist, an osteopath, or a physiatrist. Spinal manipulation, called a “spinal adjustment,” performed by subluxation-based chiropractors, however, may involve dozens of different techniques, each one different from the other, some of which do not require manual manipulation of the spine, none of which are compatible with conventional manual therapy.

Chiropractic: An Illustrated History, published in 1995 by Mosby-Year Book, listed 97 different chiropractic techniques, ranging from Activator Technique to Zindler Reflex Technique. When a patient goes from one chiropractor to another, each using a different technique that is claimed to be superior to the other, an apparent lack of standards would suggest that it might be best to bypass the chiropractor and seek manipulative care from a physical therapist or an orthopedic manual therapist.

Can neck manipulation cause a stroke?

Questions often arise about the safety of neck manipulation and the possibility of such treatment causing a stroke. With an increasing number of case reports associating neck manipulation with stroke caused by injury to vertebral and internal carotid arteries, there is good reason to question the use of neck manipulation, no matter who does it. When the neck is forcefully rotated in passive manipulation, the greatest amount of rotation takes place in the atlantoaxial joints in the upper cervical portion of the spine. There is reason to believe that extreme rotation of these joints during thrust manipulation can overstretch or injure the vertebral arteries and cause stroke, affecting the posterior portion of the brain.

Since there is little or no evidence that benefit outweighs risk when manipulating upper cervical structures, it is generally best to avoid such treatment. Unfortunately, many chiropractors, especially “upper cervical specialists,” manipulate the neck of every patient they treat in a misguided effort to correct alleged vertebral subluxations.

Should I go to a chiropractic college?

I occasionally receive letters from undergraduate students who are considering enrolling in a chiropractic college, asking which college is best. I also receive letters from chiropractic students who are beginning to doubt what they are being taught in chiropractic class rooms. There are a number of reasons why I generally advise against attending a chiropractic college, the first and foremost of which is the scientifically indefensible chiropractic subluxation theory that isolates the chiropractic profession from mainstream health care, keeping it marginal and controversial. Rejection by healthcare professionals in the scientific community, combined with the aggressive competition of subluxation-based chiropractors, makes it difficult to succeed in practice as an ethical, properly-limited chiropractor. Failure in private practice leads to unpaid student loans and very little opportunity for employment outside of private practice.

In January of 2012, the Health Resources and Services Administration (HRSA) reported that chiropractic schools had a much higher default rate on student loans than other health professional schools. More than half of the individuals on HRSA’s default list attended chiropractic school. Societal suspicion, refusal of accredited academic institutions to recognize chiropractic, the competition of physical therapists who now use manipulative therapy, and uniform criticism by the scientific community has had an adverse effect on chiropractic colleges and the income of chiropractors in private practice (who treat less than 10 percent of the population annually). A November 2012 Gallop Poll reported that only 38% of respondents rated the honesty and ethical standards of chiropractors as high, with a 70% rating for medical doctors.

According to the U.S. Department of Commerce, the average gross income per chiropractic office between January1992 and December 2007 rose at less than half the rate of inflation. This loss of purchasing power makes it difficult to justify the high cost of opening an office today if such an operation does not yield adequate income.

Enrollment in chiropractic colleges in the United States dropped precipitously─35 percent─between 1995 and 2002 and has since flat lined. As a result of a decline in the enrollment of students in chiropractic schools and a reduced demand for chiropractic services, a few chiropractic schools have labeled their institutions as a “University of Health Sciences,” including programs offering degrees or certificates in such subjects as acupuncture, Ayurvedic medicine, naturopathic medicine, oriental medicine, and massage, all of which, with the exception of massage, are questionable practices sheltered under the umbrella of alternative medicine.

My heart goes out to those ethical and well-meaning chiropractors who discover too late that they must suffer embarrassment and financial strain in years of struggle that may or may not lead to a successful practice. If I could have advised them beforehand, I would have suggested that they pursue a doctor of physical therapy degree, which would provide opportunity to use manipulative therapy along with other physical treatment methods, without dogma, societal suspicion, or rejection by the scientific community.

Are there any good chiropractors?

I am often asked why I am always badmouthing chiropractors and if I think that there are any good chiropractors. I always respond by saying, “Yes, but they are hard to find.” A chiropractor who limits care to musculoskeletal problems, with emphasis on the care of mechanical-type neck and back pain and related problems, can offer a service of value if he or she does not subscribe to chiropractic vertebral subluxation theory.

Believing that chiropractors are back specialists, patients sometimes request referral to a chiropractor. It has been my observation that physicians are often receptive to referral of a back-pain patient to a properly-limited chiropractor who offers appropriate manipulative therapy that is not readily available in local physical therapy establishments. The availability of a good chiropractor can provide physicians with a way to steer their patients away from the nonsensical, pseudoscientific services of subluxation-based chiropractors.

A physician can sometimes identify a competent chiropractor by personal correspondence that includes an exchange of office notes. Unfortunately, it seems that few chiropractors will publicly renounce the anti-medical subluxation theory that places chiropractors in competition with physicians, making it necessary to generally advise against chiropractic care.

Strip used with permission granted by Bill Janocha c/o Mort Walker. Click to embiggen.

Strip used with permission granted by Bill Janocha c/o Mort Walker. Click to embiggen.

Is it possible to reform the chiropractic profession?

I gave up trying to reform the chiropractic profession many years ago. My primary concern has long been to separate appropriate use of generic spinal manipulation from subluxation-based chiropractic. It will continue to be necessary for good chiropractors to publicly identify themselves as opponents of chiropractic subluxation theory if they are to receive any support from the scientific community. If chiropractic is ever to be developed as a properly limited musculoskeletal specialty, it must discard subluxation theory and alternative medicine practices that embrace a broad scope of ailments and then make the changes needed to specialize in conservative care for mechanical-type neck and back problems, offering a physical treatment armamentarium that includes use of spinal manipulative therapy as a treatment option.

At the present time, with state laws defining chiropractic as a method of correcting vertebral subluxations to restore and maintain health, change for the better does not seem likely anytime soon. Chiropractors who back away from subluxation theory might use alternative medicine procedures along with spinal adjustments in order to expand their scope of practice. According to National University of Health Sciences, a leading chiropractic college, “National University is a leader in the growing field of integrative medicine. We set the standard in training for careers in health care and prepare students to become first-contact, primary care physicians who are fully qualified to diagnose, treat and manage a wide range of conditions.”

It appears that chiropractors generally prefer to use spinal adjustments or a combination of spinal adjustments and alternative healing methods to treat non-musculoskeletal conditions as well as musculoskeletal problems as primary care providers rather than specialize in the care for back pain and related musculoskeletal problems, despite the fact that back pain and musculoskeletal problems are the No. 1 and No. 2 causes of disability worldwide (Vos et al. 2012).

The bottom line

When the National Board of Chiropractic Examiners published its updated version of Practice Analysis of Chiropractic in 2010, a pre-publication bulletin stated that “…the 2009 survey questionnaire did not ask about the use of applied kinesiology or any of the subluxation-based ‘adjustive procedures’ that place chiropractic in an unfavorable light.” The updated report, describing chiropractic as “the nation’s third largest primary health care profession,” stated, however, that “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.”

Chiropractic continues to be based primarily on subluxation theory, with increasing use of a variety of alternative healing methods. The question “What do chiropractors do?” continues to be difficult to answer. Persons who are not familiar with the controversial aspects of chiropractic care might simply assume that chiropractors are back specialists since they work on the back. A visit to a chiropractic office for back-pain treatment, however, where spinal adjustments or some other alternative medicine procedure might be offered as a treatment for “a wide range of problems” would suggest that chiropractic is certainly not properly limited and is not a specialty or subspecialty in the care of back pain.


Sam Homola is a retired chiropractor who has been expressing his views about the benefits of appropriate use of spinal manipulation (as opposed to use of such treatment based on chiropractic subluxation theory) since publication of his book Bonesetting, Chiropractic, and Cultism in 1963. He retired from private practice in 1998. His many posts for are archived here.




  • Samuel Homola is a retired chiropractor who has been expressing his views about the benefits of appropriate use of spinal manipulation (as opposed to use of such treatment based on chiropractic subluxation theory) since publication of his book Bonesetting, Chiropractic, and Cultism in 1963. He retired from private practice in 1998. His 15 published books include Inside Chiropractic, published by Prometheus Books in 1999.

Posted by Sam Homola

Samuel Homola is a retired chiropractor who has been expressing his views about the benefits of appropriate use of spinal manipulation (as opposed to use of such treatment based on chiropractic subluxation theory) since publication of his book Bonesetting, Chiropractic, and Cultism in 1963. He retired from private practice in 1998. His 15 published books include Inside Chiropractic, published by Prometheus Books in 1999.