What is a Chiropractor?

Chiropractors are primarily mechanical providers of care (adjustments, exercise, tissue work, etc.). A spinal adjustment is a manipulation that is delivered in a specific line-of-drive. Chiropractic education emphasizes mechanical care. Chiropractors are not trained in pharmacology, and/or drugs. Those are outside of their scope of license. Yet most chiropractic patients are taking medication or drugs for their symptoms prior to initiating chiropractic care.

Spinal manipulation and chiropractic-type healthcare procedures have a long history (1, 2, 3). For at least 2,500 years, spinal manipulation has been practiced in many parts of the world, primarily to treat musculoskeletal disorders. Ancient evidence for the use of spinal manipulation has been documented in: Bohemian (Czechoslovakia), China, Egypt, England, Finland, Greece, India, Japan, Latin America, Norway, Russia, and Wales.

In 2007, a study published in The Journal of Manual & Manipulative Therapy notes (3):

“Manipulative therapy has known a parallel development throughout many parts of the world. The earliest historical reference to the practice of manipulative therapy in Europe dates back to 400 BCE.”

“Historically, manipulation can trace its origins from parallel developments in many parts of the world where it was used to treat a variety of musculoskeletal conditions, including spinal disorders.”

“It is acknowledged that spinal manipulation is and was widely practiced in many cultures and often in remote world communities such as by the Balinese of Indonesia, the Lomi-     Lomi of Hawaii, in areas of Japan, China and India, by the shamans of Central Asia, by sabodors in Mexico, by bone setters of Nepal as well as by bone setters in Russia and Norway.”

“Historical reference to Greece provides the first direct evidence of the practice of spinal manipulation.”

“Hippocrates (460–385 BCE), who is often referred to as the father of medicine, was the first physician to describe spinal manipulative techniques.”

“Claudius Galen (131–202 CE), a noted Roman surgeon, provided evidence of manipulation including the acts of standing or walking on the dysfunctional spinal region.”

“Avicenna (also known as the doctor of doctors) from Baghdad (980–1037 CE) included descriptions of Hippocrates’ techniques in his medical text The Book of Healing.”

In her 1990 book, Mutant Message Down Under, Marlo Morgan chronicles the journey of a middle-aged, white, American woman (herself) with a group of 62 desert Aborigines across the continent of Australia (1). Morgan chronicled a cultural habit, estimated to be millennia old, at the end of each day’s nomadic journey: members of the group spinal manipulating each other. Marlo Morgan notes (1):

“Evenings were a real joy with the tribal people. They told stories, sang, danced, played games, had heart to heart chats. This was a real time for sharing. There was always some activity while we waited for the food to be prepared. They did a lot of massaging and rubbing of each other’s shoulders, backs, even their scalps. I saw them manipulating necks and spines.”

For most of this history, the practitioners of manipulation were known as bonesetters (3). In the United States, in the year 1874, second-generation medical physician Andrew Taylor Still became disillusioned with medicine following the death (from disease) of three of his children.

Dr. Still conceived a theory whereby health could only be maintained and, therefore, disease defeated, by maintaining normal function of the musculoskeletal system (3). In 1892, Still established the American Osteopathic College in Kirksville, Missouri. By the time of his death in 1917, 3,000 Doctors of Osteopathy had graduated from his school.

In 1895, “natural healer” Daniel David (DD) Palmer reasoned that when a vertebra was out of alignment, it caused pressure on nerves. In 1897, Palmer opened his first college, The Palmer College of Cure, now known as Palmer College of Chiropractic, located in Davenport, Iowa (3).

History records that a major boost to the chiropractic profession occurred as a consequence of World War II (WWII) (4). At the conclusion of the war in 1945, approximately 16 million soldiers (primarily men) became instantly unemployed. Fortunately, the GI bill paid for their chiropractic college education, forever changing the profession: (4):

“The G. I. Bill at the end of World War II enabled thousands of returning soldiers to bolster the ranks of the chiropractic profession.”

“This influx seemed to provide an impetus that would propel the chiropractic profession to today’s status where it boasts 35 schools and colleges worldwide and, in the Western world at least, it is second only to the medical profession as a primary care healthcare provider.”

Today, there are 18 chiropractic colleges in the United States and many more throughout the world (5). Some of the chiropractic colleges are universities that grant academic degrees in addition to the Doctor of Chiropractic degree (DC). Others only grant Doctor of Chiropractic degrees.

In the 1970s, the United States federal government took a major interest in chiropractic education in the US. The United States Department of Education now oversees chiropractic education by recognizing the Council for Chiropractic Education (CCE) (5):

“CCE maintains recognition by the United States Department of Education as the national accrediting body for Doctor of Chiropractic Programs and chiropractic solitary purpose institutions of higher education.”

All 18 of the chiropractic colleges in the United States are accredited by the Council for Chiropractic Education.

In the United States, the licensure of chiropractors is controlled by the individual states, and all 50 U.S. states officially license chiropractors, allowing them to practice with their Doctor of Chiropractic degree (DC). Chiropractors are “portal of entry” care providers, which means (in part) that the public may choose chiropractic care without requiring a referral from another health care provider.

As a result of their education and examination procedures, chiropractors are legally allowed to provide several services to their patients. These include physical therapy, exercise, tissue work, dietary advice, use of supplements, the taking of and the interpretation of x-rays, etc. But the central core of chiropractic clinical practice is the use of mechanical care, and the primary form of mechanical care is specific line-of-drive manipulation (the chiropractic adjustment).

A typical chiropractic visit involves an assessment of posture and joint motion (possibly with the use of x-rays), helping the chiropractor assess the way his/her patient exists and functions mechanically in a gravity environment. Abnormal findings are usually treated mechanically and primarily with the use of the chiropractic adjustment.

Why do People go to Chiropractors?

Spinal manipulation is one of the most ancient forms of treatment for musculoskeletal complaints, primarily for back pain and neck pain. Mechanical function in a gravity environment influences how people feel and function. Chiropractic adjusting influences mechanical integrity in a positive way, thereby improving both pain and function. Ninety-three percent of patients who chose to initially see a chiropractor do so for spinal pain complaints (6). Satisfaction among patients with these complaints is exceptionally high (6).

How Does Chiropractic Care Differ from Traditional Medical Care?

Medical providers (medical doctors) are primarily chemical providers of care (pharmacology). Government gives drug companies patents for their products, allowing for hundreds of billions of dollars in profits. Government does not grant patents on natural products, even if they work great, which is one of the reasons we hear much less about them. Media advertising is very expensive ($8 million dollars for a 30 second television advertisement during the 2026 Super Bowl). Few non-patentable products generate enough revenue to afford media advertising.

Chiropractors, as noted above, are primarily mechanical providers of care (adjustments, exercise, tissue work, etc.). Chiropractic education stresses these mechanical interventions, and it also stresses evolutionary biology.

Most chiropractors think of and consider evolutionary biology in their clinical assessment and approach. They often reference the great Ukrainian American geneticist and evolutionary biologist Theodosius Dobzhansky (d. 1975). Dr. Dobzhansky was widely published in books and in peer reviewed scientific journals. He is best known for the statement (7):

“Nothing in Biology Makes Sense Except in the Light of Evolution”

An understanding of evolutionary biology establishes the biomechanical need for mechanical-based care. The evolutionary biological basis for the need for mechanical-based care is briefly summarized here (8, 9, 10):

• All species, including humans, have to survive long enough to create the next generation (make babies).
• Throughout evolutionary history, the primary killer of humans was infections (not heart disease, stroke, and cancer which have overtaken infection in the past century).
• Humans evolved mechanisms to help them survive infections.
• The primary protective mechanism was inflammation. Inflammation served two purposes: 1) The inflammatory cascade could kill infection as part of the innate immune response. 2) The inflammation would trigger a fibrosis response that would “wall off” the infectious microbes by creating a barrier to their motion. The resolution of inflammation is fibrosis.

This sequence dominated human evolution for millennia. But here is the problem: tissue injury and/or chronic tissue stress also create an inflammatory cascade, and it is the same sequence triggered by infection (8, 9, 10, 11). The appropriate fibrotic response to limit infection is excessive when there is no infection. Tissue injury and stress that trigger inflammation tend to “over heal” with fibrosis, and this fibrosis is, in and of itself, harmful to the person. This aseptic inflammation and fibrosis harms people because it is weaker, stiffer, more tender, and it alters local neurology, including increasing pain.

Yet, these fibrotic changes can be remodeled (improved) with appropriately applied mechanical forces. There are no drugs that remodel these tissues. The global leader in the application of the remodeling forces is the chiropractic profession. The benefits are improved motion, greater function, and reduced pain.

How Does Chiropractic Care Differ from Traditional Physical Therapy Care?

Chiropractic and Physical Therapy are separate professions, yet they both emphasize mechanical-based care. Legally, they have different licensing requirements, testing, and different oversight boards. Yet there are many overlaps in the education of chiropractors and physical therapists. Consequently, there are overlaps in the practice of chiropractic and physical therapy. These overlaps are officially within the scope of practice of both professions.

Traditionally, physical therapy uses modalities (electrical and others), physical interventions (tissue work, massage, stretching, etc.), orthopedic appliances (braces, supports, etc.), and advice (exercise, ergonomics, etc.) to address different stages of a pathophysiological process. Chiropractors are similarly trained in the use of these modalities and approaches, and hence they are legal components of chiropractic clinical practice. However, the primary clinical emphasis of chiropractic is different than that of physical therapy. Chiropractic clinical practice emphasizes joint (primarily spinal) manipulation.

Spinal manipulation uses the vertebrae (usually the transverse and/or spinous process) as a lever to influence tissue integrity and improve the movement parameters of spinal joints. It is established that joint manipulation can influence a larger range of tissue problems than exercise or mobilization techniques. Hence, joint manipulation is able to help a larger range of musculoskeletal problems, especially in more chronic cases (12, 13, 14, 15, 16). These improvements are achieved quickly and simply, and without injury risk. The musculoskeletal benefits of joint manipulation tend to be long lasting (17, 18).

Over the decades, there have been a number of studies comparing traditional physical therapy clinical practice to traditional chiropractic clinical practice (joint manipulation), including:

••••

In 1969, a study was published in The Australian Journal of Physiotherapy, titled (19):

Low Back Pain and Pain Resulting From Lumbar Spine Conditions:
A Comparison of Treatment Results

This study used 184 subjects, half were treated with heat/massage/exercise and half were treated with mobilization/manipulation. The authors found:

“[The results] indicate that treatment of low back pain and pain resulting from low back conditions by passive movement techniques of mobilization and manipulation is a more satisfactory method than by standard physiotherapy of heat, massage, and exercise, in regards to both results and number of treatments required.”

“The survey also indicated that by using techniques of mobilization good results can be obtained with patients even if neurological signs are present.”

••••

This study by Edwards (19) was reviewed in the 1990 reference text, White and Panjabi’s Clinical Biomechanics of the Spine. Drs. White and Panjabi make the following points pertaining to the Edwards article (20):

“A well-designed, well executed, and well-analyzed study.”

“This study certainly supports the efficacy of spinal manipulative therapy in comparison with heat, massage, and exercise. The results (80–95% satisfactory) are impressive in comparison with any form of therapy.”

••••

In 1990, a study was published in the British Medical Journal, titled (21):

Low Back Pain of Mechanical Origin:
Randomized Comparison of Chiropractic and Hospital Outpatient Treatment

This study was a randomized comparison of chiropractic and hospital physical therapy outpatient treatment in the management of low back pain. The trial involved 741 patients; 84% of the hospital patients were treated with physical therapy. The patients were followed for a period between 1–3 years. The authors concluded:

“Chiropractic treatment was more effective than hospital outpatient management, mainly for patients with chronic or severe back pain.”

“There is, therefore, economic support for use of chiropractic in low back pain, though the obvious clinical improvement in pain and disability attributable to chiropractic treatment is in itself an adequate reason for considering the use of chiropractic.”

“Chiropractic was particularly effective in those with fairly intractable pain-that is, those with a history of severe pain.”

“Patients treated by chiropractors were not only no worse off than those treated in hospital but almost certainly fared considerably better and that they maintained their improvement for at least two years.”

“The results leave little doubt that chiropractic is more effective than conventional hospital [physical therapy] out patient treatment.”

This observation led to an editorial follow-up in a different journal, The Lancet, which stated (22):

Chiropractors and Low Back Pain

“[The study] showed a strong and clear advantage for patients with chiropractic.”

The advantage for chiropractic over conventional hospital treatment was “not a trivial amount” and “reflects the difference between having mild pain, the ability to lift heavy weights without extra pain, and the ability to sit for more than one hour, compared with moderate pain, the ability to lift heavy weights only if they are conveniently positioned, and being unable to sit for more than 30 minutes.”

“This highly significant difference occurred not only at 6 weeks, but also for 1, 2, and even (in 113 patients followed so far) 3 years after treatment.”

“Surprisingly, the difference was seen most strongly in patients with chronic symptoms.”

“The trial was not simply a trial of manipulation but of management” as 84% of the hospital-managed patients had [physiotherapy] manipulations.

“Chiropractic treatment should be taken seriously by conventional medicine, which means both doctors and physiotherapists.”

“Physiotherapists need to shake off years of prejudice and take on board the skills that the chiropractors have developed so successfully.”

••••

In 1996, a study was published in the journal Injury, titled (23):

Chiropractic Treatment of Chronic ‘Whiplash’ Injuries

This was a retrospective study that was undertaken to determine the effects of chiropractic spinal manipulation in a group of 28 patients who had been referred with chronic ‘whiplash’ syndrome. These patients had all initially been treated with anti-inflammatories, soft collars, and physiotherapy. They were subsequently referred for chiropractic spinal manipulation.

Following chiropractic care, 93% of the patients had improved. These authors state:

“The results of this retrospective study would suggest that benefits can occur in over 90% of patients undergoing chiropractic treatment for chronic whiplash injury.”

••••

In 2002, a study was published in the Annals of Internal Medicine, and titled (24):

Manual Therapy, Physical Therapy, or Continued Care by a General Practitioner for Patients with Neck Pain:
A Randomized Controlled Trial

The authors defined “manipulation” as:

“Orthopedic manipulative (manual) therapy is a specialization within physical therapy and provides comprehensive conservative management for pain and other symptoms of neuro-musculo-articular dysfunction in the spine and extremities.”

The authors compared the effectiveness of manual therapy, physical therapy, and care by a general practitioner physician in the treatment of neck pain, using a randomized controlled trial design. The study involved 183 patients. These authors concluded:

“Manual therapy scored consistently better than the other two interventions on most outcome measures.”

“In daily practice, manual therapy is a favorable treatment option for patients with neck pain compared with physical therapy or continued care by a general practitioner.”

“The success rates for manual therapy were statistically    significantly higher than those for physical therapy.”

“Manual therapy scored better than physical therapy on all  outcome measures…”

“Patients receiving manual therapy had fewer absences from work than patients receiving physical therapy or continued care.”

“Manual therapy seems to be a favorable treatment option for patients with neck pain.”

“Primary care physicians should consider manual therapy when treating patients with neck pain.”

••••

In 2004, a study was published in the Journal of Whiplash & Related Disorders titled (25):

Manipulative Treatment vs. Conventional Physiotherapy Treatment in Whiplash Injury:
A Randomized Controlled Trial

The authors are trained as physical therapists. They state that the goal of joint manipulation is to restore maximal, pain-free movement of the musculoskeletal system. The aim of this clinical trial is to compare the results obtained with a manipulative protocol with the results obtained with a conventional physiotherapy treatment in patients suffering from whiplash injury. The study included 380 acute whiplash injured subjects. The authors concluded:

“Patients who had received manipulative treatment needed fewer sessions to complete the treatment than patients who had received physiotherapy treatment.”

“Results showed that the manipulative group had more benefits than the physiotherapy group.”

“Our clinical experience with these [whiplash-injured] patients has demonstrated that manipulative treatment gives better results than conventional physiotherapy treatment.”

“This clinical trial has demonstrated that head and neck pain decrease with fewer treatment sessions in response to a manipulative treatment protocol as compared to a physiotherapy treatment protocol among patients diagnosed with acute whiplash injury.”

“Manipulative treatment is more effective in the management of whiplash injury than conventional physiotherapy treatment.”

••••

In 2016, a study was published in the Journal of Occupational Rehabilitation titled (26):

Association Between the Type of First Healthcare Provider and the Duration of Financial Compensation for Occupational Back Pain

The objective of this study was to compare the duration of financial compensation and the occurrence of a second episode of compensation for back pain among injured workers seen by three types of first healthcare providers (physicians, chiropractors, and physiotherapists). The study used a cohort of 5,511 injured workers who were followed for a period of two years. The authors found:

“Physiotherapists showed the longest duration of compensation, and chiropractors showed the shortest.”

Over the first 149 days, the “workers who first sought care from a chiropractor had a significantly greater hazard of ending their compensation episode compared with the workers who first consulted a physician and those who first consulted a physiotherapist.”

“Physiotherapists were associated with higher odds of a second episode of financial compensation.”

“In accordance with our findings, workers who first sought chiropractic care were less likely to be work-disabled after 1 year compared with workers who first sought other types of medical care.”

“Chiropractic patients experience the shortest duration of compensation, and physiotherapy patients experience the longest.”

“The physiotherapy patients were also more likely to experience a second episode of compensation. Our results raised concerns regarding the use of physiotherapists as gatekeepers of Ontario’s worker’s compensation system.”

“These differences raise concerns regarding the use of physiotherapists as gatekeepers for the worker’s compensation system.”

Summary

Mechanical providers of care have helped patients for millennia. Since 1895, in the United States and other countries around the world, the primary providers of mechanical care are chiropractors. Despite many obstacles and often strong headwinds, the chiropractic profession has held steadfast to its mechanical-based care roots. For more than a century, chiropractic clinicians and scientists have continued to explore and refine their mechanical applications of care, especially as related to musculoskeletal pain syndromes.

REFERENCES:

1. Morgan M; Mutant Message Down Under; 1990.
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19. Edwards BC; Low Back Pain and Pain Resulting From Lumbar Spine Conditions: A Comparison of Treatment Results; The Australian Journal of Physiotherapy; September 1969; Vol. 15; No. 3; pp. 104-110.
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21. Meade TW, Dyer S, Browne W, Townsend J, Frank OA; Low back pain of mechanical origin: Randomized comparison of chiropractic and hospital outpatient treatment; British Medical Journal; Vol. 300; June 2, 1990; pp. 1431-1437.
22. editorial; Chiropractors and Low Back Pain; Lancet; July 28, 1990; p. 220.
23. Woodward MN, Cook JCH, Gargan MF, Bannister GC; Chiropractic Treatment of Chronic ‘Whiplash’ Injuries; Injury; November 1996; Vol. 27; No. 9; pp. 643-645.
24. Hoving JC, Koes BW, de Vet HCW, van der Windt DAWM, Assendelft WJJ, Mameren H, Devillé WLJM; Manual Therapy, Physical Therapy, or Continued Care by a General Practitioner for Patients with Neck Pain; A Randomized Controlled Trial; Annals of Internal Medicine; May 21, 2002; 136; No. 10; pp. 713-722.
25. Fernández-de-las-Peñas C, Fernández-Carnero J, Palomeque del Cerro L; Manipulative Treatment vs. Conventional Physiotherapy Treatment in Whiplash Injury: A Randomized Controlled Trial; Journal of Whiplash & Related Disorders; 2004; Vol. 3; No. 2.
26. Blanchette AM, Rivard M, Dionne CE, Hogg-Johnson S, Steenstra I; Association Between the Type of First Healthcare Provider and the Duration of Financial Compensation for Occupational Back Pain; Journal of Occupational Rehabilitation; September 17, 2016; Vol. 27; No. 3; pp. 382-392.