Chiropractic is a health care profession concerned with the diagnosis, treatment and prevention of disorders of the neuromusculoskeletal system and the effects of these disorders on general health. It is generally categorized as complementary and alternative medicine (CAM). Although chiropractors have many attributes of primary care providers, chiropractic has more of the attributes of a medical specialty like dentistry or podiatry.
The main chiropractic treatment technique involves manual therapy, including manipulation of the spine, other joints, and soft tissues; treatment also includes exercises and health and lifestyle counseling. Traditional chiropractic assumes that a vertebral subluxation interferes with the body’s innate intelligence, a vitalistic notion ridiculed by the scientific and healthcare communities. A large number of chiropractors want to separate themselves from the traditional vitalistic concept of innate intelligence.
D.D. Palmer founded chiropractic in the 1890s, and his son B.J. Palmer helped to expand it in the early 20th century. It has two main groups: “straights”, now the minority, emphasize vitalism, innate intelligence and spinal adjustments, and consider vertebral subluxations to be the cause of all disease; “mixers”, the majority, are more open to mainstream views and conventional medical techniques, such as exercise, massage, and ice therapy.
Chiropractic is well established in the U.S., Canada and Australia and is the “third largest of the doctored health professions (behind only medicine and dentistry)”. It overlaps with other manual-therapy professions, including massage therapy, osteopathy, and physical therapy. Most who seek chiropractic care do so for low back pain.
Throughout its history, chiropractic has been controversial. For most of its existence it has battled with mainstream medicine, sustained by pseudoscientific ideas such as subluxation and innate intelligence that are not based on solid science. Despite the general consensus of public health professionals regarding the benefits of vaccination, among chiropractors there are significant disagreements over the subject, which has led to negative impacts on both public vaccination and mainstream acceptance of chiropractic. The American Medical Association called chiropractic an “unscientific cult” and boycotted it until losing an antitrust case in 1987. Chiropractic has developed a strong political base and sustained demand for services; in recent decades, it has gained more legitimacy and greater acceptance among medical physicians and health plans in the U.S., and the principles of evidence-based medicine have been used to review research studies and generate practice guidelines.
Many studies of treatments used by chiropractors have been conducted, often with conflicting results. Manual therapies commonly used by chiropractors are effective for the treatment of low back pain, and might also be effective for the treatment of lumbar disc herniation with radiculopathy, neck pain, some forms of headache, and some extremity joint conditions. The efficacy and cost-effectiveness of maintenance chiropractic care are unknown.
Chiropractic care is generally safe when employed skillfully and appropriately. Spinal manipulation is frequently associated with mild to moderate adverse effects, with serious or fatal complications in rare cases. A systematic review found that the risk of death from manipulations to the neck outweighs the benefits. This has no relevance to manipulations performed below the cervical region.
Chiropractic’s early philosophy was rooted in vitalism, spiritual inspiration and rationalism. A philosophy based on deduction from irrefutable doctrine helped distinguish chiropractic from medicine, provided it with legal and political defenses against claims of practicing medicine without a license, and allowed chiropractors to establish themselves as an autonomous profession. This “straight” philosophy, taught to generations of chiropractors, rejects the inferential reasoning of the scientific method, and relies on deductions from vitalistic first principles rather than on the materialism of science.
However, most practitioners currently accept the importance of scientific research into chiropractic, and most practitioners are “mixers” who attempt to combine the materialistic reductionism of science with the metaphysics of their predecessors and with the holistic paradigm of wellness; a 2008 commentary proposed that chiropractic actively divorce itself from the straight philosophy as part of a campaign to eliminate untestable dogma and engage in critical thinking and evidence-based research.
Although a wide diversity of ideas currently exists among chiropractors, they share the belief that the spine and health are related in a fundamental way, and that this relationship is mediated through the nervous system. Chiropractors examine the biomechanics, structure and function of the spine, along with its effects on the musculoskeletal andnervous systems and what they believe to be its role in health and disease.
Chiropractic philosophy includes the following perspectives:
Straight chiropractors adhere to the philosophical principles set forth by D.D. and B.J. Palmer, and retainmetaphysical definitions and vitalistic qualities. Straight chiropractors believe that vertebral subluxation leads to interference with an “innate intelligence” exerted via the human nervous system and is a primary underlying risk factor for many diseases. Straights view the medical diagnosis of patient complaints (which they consider to be the “secondary effects” of subluxations) to be unnecessary for chiropractic treatment. Thus, straight chiropractors are concerned primarily with the detection and correction of vertebral subluxation via adjustment and do not “mix” other types of therapies into their practice style.
Their philosophy and explanations are metaphysical in nature and they prefer to use traditional chiropractic lexicon terminology (i.e. perform spinal analysis, detect subluxation, correct with adjustment, etc.). They prefer to remain separate and distinct from mainstream health care. Although considered the minority group, “they have been able to transform their status as purists and heirs of the lineage into influence dramatically out of proportion to their numbers.”
Mixer chiropractors “mix” diagnostic and treatment approaches from osteopathic, medical, and chiropractic viewpoints. Unlike straight chiropractors, mixers believe subluxation is one of many causes of disease, and they incorporate mainstream medical diagnostics and employ many treatments including conventional techniques ofphysical therapy such as exercise, massage, ice packs, and moist heat, along with nutritional supplements,acupuncture, homeopathy, herbal remedies, and biofeedback. Mixers tend to be open to mainstream medicine and are the majority group.
Although mixers are the majority group, many of them retain some belief in vertebral subluxation as shown in a 2003 survey of 1100 North American chiropractors, which found that 88% wanted to retain the term “vertebral subluxation complex”, and that when asked to estimate the percent of disorders of internal organs (such as the heart, the lungs, or the stomach) that subluxation significantly contributes to, the mean response was 62%.Despite this finding, a 2008 survey of 6000 American chiropractors demonstrated that most chiropractors seem to believe that a subluxation-based clinical approach may be of limited utility for addressing visceral disorders, and greatly favored non-subluxation-based clinical approaches for such conditions.
Vertebral subluxationPalmer hypothesized that vertebral joint misalignments, which he termed vertebral subluxations, interfered with the body’s function and its inborn (innate) ability to heal itself. D.D. Palmer repudiated his earlier theory that vertebral subluxations caused pinched nerves in the intervertebral spaces in favor of subluxations causing altered nerve vibration, either too tense or too slack, affecting the tone (health) of the end organ. D.D. Palmer, using a vitalistic approach, imbued the term subluxation with a metaphysical and philosophical meaning. He qualified this by noting that knowledge of innate intelligence was not essential to the competent practice of chiropractic. This concept was later expanded upon by his son, B.J. Palmer and was instrumental in providing the legal basis of differentiating chiropractic medicine from conventional medicine. In 1910, D.D. Palmer theorized that the nervous system controlled health:
“Physiologists divide nerve-fibers, which form the nerves, into two classes, afferent and efferent. Impressions are made on the peripheral afferent fiber-endings; these create sensations that are transmitted to the center of the nervous system. Efferent nerve-fibers carry impulses out from the center to their endings. Most of these go to muscles and are therefore called motor impulses; some are secretory and enter glands; a portion are inhibitory their function being to restrain secretion. Thus, nerves carry impulses outward and sensations inward. The activity of these nerves, or rather their fibers, may become excited or allayed by impingement, the result being a modification of functionality—too much or not enough action—which is disease.”
Vertebral subluxation, a core concept of traditional chiropractic, remains unsubstantiated and largely untested, and a debate about whether to keep it in the chiropractic paradigm has been ongoing for decades. In general, critics of traditional subluxation-based chiropractic (including chiropractors) are skeptical of its clinical value, dogmatic beliefs and metaphysical approach. While straight chiropractic still retains the traditional vitalistic construct espoused by the founders, evidence-based chiropractic suggests that a mechanistic view will allow chiropractic care to become integrated into the wider health care community. This is still a continuing source of debate within the chiropractic profession as well, with some schools of chiropractic still teaching the traditional/straight subluxation-based chiropractic, while others have moved towards an evidence-based chiropractic that rejects metaphysical foundings and limits itself to primarily neuromusculoskeletal conditions.
A 2003 survey of North American chiropractors found that 88% wanted to retain the term vertebral subluxation complex, and that when asked to estimate the percent of disorders of internal organs (such as the heart, the lungs, or the stomach) that subluxation significantly contributes to, the mean response was 62%. In 2005, the chiropractic subluxation was defined by the World Health Organization 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.” This differs from the medical definition of subluxation as a significant structural displacement, which can be seen with static imaging techniques such as X-rays.
The 2008 book Trick or Treatment states “X-rays can reveal neither the subluxations nor the innate intelligence associated with chiropractic philosophy, because they do not exist.” Attorney David Chapman-Smith, Secretary-General of the World Federation of Chiropractic, has stated that “Medical critics have asked how there can be a subluxation if it cannot be seen on x-ray. The answer is that the chiropractic subluxation is essentially a functional entity, not structural, and is therefore no more visible on static x-ray than a limp or headache or any other functional problem.” The General Chiropractic Council, the statutory regulatory body for chiropractors in the United Kingdom, states that the chiropractic vertebral subluxation complex “is not supported by any clinical research evidence that would allow claims to be made that it is the cause of disease.”
Scope of practiceChiropractors, also known as doctors of chiropractic or chiropractic physiciansin many jurisdictions, emphasize the conservative management of the neuromusculoskeletal system without the use of medicines or surgery, with special emphasis on the spine. Chiropractic combines aspects from mainstream and alternative medicine, and there is no agreement about how to define the profession: although chiropractors have many attributes of primary care providers, chiropractic has more of the attributes of a medical specialty like dentistry or podiatry.
It has been proposed that chiropractors specialize in nonsurgical spine care, instead of attempting to also treat other problems, but the more expansive view of chiropractic is still widespread. Mainstream health care and governmental organizations such as the World Health Organization consider chiropractic to be complementary and alternative medicine (CAM).
A 2008 study reported that 31% of surveyed chiropractors categorized chiropractic as CAM, 27% as integrated medicine, and 12% as mainstream medicine. Aligning with conventional medicine could give chiropractors more university affiliation and access to hospitals and long-term facilities; aligning with the CAM movement could bring more patients looking for nonmedical approaches.
Chiropractors use x-ray radiography to examine the bone structure of a patient.
The practice of chiropractic medicine involves a range of diagnostic methods including skeletal imaging, observational and tactile assessments, and orthopedic and neurological evaluation. A chiropractor may also refer a patient to an appropriate specialist, or co-manage with another health care provider. Common patient management involves spinal manipulation (SM) and other manual therapies to the joints and soft tissues, rehabilitative exercises, health promotion, electrical modalities, complementary procedures, and lifestyle counseling.
Chiropractors are not licensed to write medical prescriptions or perform major surgery in the U.S., but that recently changed when New Mexico became the first state to allow “advanced practice” trained chiropractors the ability to prescribe certain medications. Their scope of practice varies by state, based on inconsistent views of chiropractic care: some states, such as Iowa, broadly allow treatment of “human ailments”; some, such as Delaware, use vague concepts such as “transition of nerve energy” to define scope of practice; others, such as New Jersey, specify a severely narrowed scope.
States also differ over whether chiropractors may conduct laboratory tests or diagnostic procedures, dispense dietary supplements, or use other therapies such as homeopathy and acupuncture; in Oregon they can become certified to perform minor surgery and to deliver children via natural childbirth. A 2003 survey of North American chiropractors found that a slight majority favored allowing them to write prescriptions for over-the-counter drugs.
A 2010 survey found 72% of Switzerland chiropractors judged the current allowance in Switzerland to prescribing nonprescription medication as an advantage for chiropractic treatment. A related field, veterinary chiropractic, applies manual therapies to animals and is recognized in a few U.S. states, but is not recognized by the American Chiropractic Association as being chiropractic.
A treatment table at a chiropractic office.
Chiropractic overlaps with several other manual-therapy professions, including massage therapy, osteopathy, physical therapy, and sports medicine. Chiropractic is autonomous and competitive with mainstream medicine, and osteopathy outside the U.S. remains primarily a manual medical system; physical therapists work alongside and cooperate with mainstream medicine, and osteopathic medicine in the U.S. has merged with the medical profession. Members distinguish these competing professions with rhetorical strategies that include claims that, compared to other professions, chiropractors heavily emphasize spinal manipulation, tend to use firmer manipulative techniques, and promote maintenance care; that osteopaths use a wider variety of treatment procedures; and that physical therapists emphasize machinery and exercise.
Treatment techniquesSpinal manipulation, which chiropractors call “spinal adjustment” or “chiropractic adjustment”, is the most common treatment used in chiropractic care. Spinal manipulation is a passive manual maneuver during which a three-joint complex is taken past the normal range of movement, but not so far as to dislocate or damage the joint. Its defining factor is a dynamic thrust, which is a sudden force that causes an audible release and attempts to increase a joint’s range of motion.
Neck manipulations are high-velocity, short-lever thrusts with rotation beyond the physiological range of motion. High-velocity, low-amplitude spinal manipulation (HVLA-SM) thrusts have physiological effects that signal neural discharge from paraspinal muscle tissues, depending on duration and amplitude of the thrust are factors of the degree in paraspinal muscle spindles activation. Clinical skill in employing HVLA-SM thrusts depends on the ability of the practitioner to handle the duration and magnitude of the load. More generally, spinal manipulative therapy (SMT) describes techniques where the hands are used to manipulate, massage, mobilize, adjust, stimulate, apply traction to, or otherwise influence the spine and related tissues.
There are several schools of chiropractic adjustive techniques, although most chiropractors mix techniques from several schools. The following adjustive procedures were received by more than 10% of patients of licensed U.S. chiropractors in a 2003 survey:[Diversified technique (full-spine manipulation, employing various techniques), extremity adjusting, Activator technique (which uses a spring-loaded tool to deliver precise adjustments to the spine), Thompson Technique (which relies on a drop table and detailed procedural protocols), Gonstead (which emphasizes evaluating the spine along with specific adjustment that avoids rotational vectors), Cox/flexion-distraction (a gentle, low-force adjusting procedure which mixes chiropractic with osteopathic principles and utilizes specialized adjusting tables with movable parts), adjustive instrument, Sacro-Occipital Technique (which models the spine as a torsion bar), Nimmo Receptor-Tonus Technique, Applied Kinesiology (which emphasises "muscle testing" as a diagnostic tool), and cranial. Medicine-assisted manipulation, such as manipulation under anesthesia, involves sedation or local anesthetic and is done by a team that includes an anesthesiologist; a 2008 systematic review did not find enough evidence to make recommendations about its use for chronic low back pain.
Many other procedures are used by chiropractors for treating the spine, other joints and tissues, and general health issues. The following procedures were received by more than one-third of patients of licensed U.S. chiropractors in a 2003 survey: Diversified technique (full-spine manipulation; mentioned in previous paragraph), physical fitness/exercise promotion, corrective or therapeutic exercise, ergonomic/postural advice, self-care strategies,activities of daily living, changing risky/unhealthy behaviors, nutritional/dietary recommendations, relaxation/stress reduction recommendations, ice pack/cryotherapy, extremity adjusting (also mentioned in previous paragraph),trigger point therapy, and disease prevention/early screening advice.
A 2010 study describing Belgium chiropractors and their patients found chiropractors in Belgium mostly focus on neuromusculoskeletal complaints in adult patients, with emphasis on the spine. The diversified technique is the most often applied technique at 93%, followed by the Activator mechanical-assisted technique at 41%. A 2009 study assessing chiropractic students giving or receiving spinal manipulations while attending a U.S. chiropractic college found Diversified, Gonstead, and upper cervical manipulations are frequently used methods.