Chiropractic is a form of health care that focuses on the relationship between the body's structure, primarily of the spine, and function. Doctors of chiropractic, who also are called chiropractors or chiropractic physicians, use a type of hands-on therapy called manipulation (or adjustment) as their core clinical procedure. While there are some differences in beliefs and approaches within the chiropractic profession, this article will give you a general overview of chiropractic, discuss scientific research findings on chiropractic treatment for low-back pain, and suggest other sources of information.

What Is Chiropractic?

The word "chiropractic" combines the Greek words cheir (hand) and praxis (action) and means "done by hand." Chiropractic is an alternative medical system and takes a different approach from conventional medicine in diagnosing, classifying and treating medical problems.

The basic concepts of chiropractic can be described as follows:

• The body has a powerful self-healing ability.

• The body's structure (primarily that of the spine) and its function are closely related, and this relationship affects health.

Chiropractic therapy is given with the goals of normalizing this relationship between structure and function and assisting the body as it heals.

What Is the History of the Discovery and Use of Chiropractic?

Chiropractic is a form of spinal manipulation, which is one of the oldest healing practices. Spinal manipulation was described by Hippocrates in ancient Greece.^1-3 In 1895, Daniel David Palmer founded the modern profession of chiropractic in Davenport, Iowa. Palmer was a self-taught healer and a student of healing philosophies of the day. He observed that the body has a natural healing ability that he believed was controlled by the nervous system. He also believed that subluxations, or misalignments of the spine (a concept that had already existed in the bonesetter and osteopathic traditions), interrupt or interfere with this "nerve flow." Palmer suggested that if an organ does not receive its normal supply of impulses from the nerves, it can become diseased. This line of thinking led him to develop a procedure to "adjust" the vertebrae, the bones of the spinal column, with the goal of correcting subluxations.

Some chiropractors continue to view subluxation as central to chiropractic health care.² However, other chiropractors no longer view the subluxation theory as a unifying theme in health and illness or as a basis for their practice. Other theories as to how chiropractic might work have been developed.

Who Uses Chiropractic and For What Health Problems?

In 1997, it was estimated that Americans made nearly 192 million visits a year to chiropractors.⁴ More than 88 million of those visits were to treat back or neck pain.⁵ In one recent survey, more than 40 percent of patients receiving chiropractic care were being treated for back or low-back problems.⁶ More than half of those surveyed said that their symptoms were chronic. Conditions commonly treated by chiropractors include back pain, neck pain, headaches, sports injuries and repetitive strains. Patients also seek treatment of pain associated with other conditions, such as arthritis.⁷

Low-back pain is a common medical problem, occurring in up to one-quarter of the population each year. Most people experience significant back pain at least once during their lifetime.⁸ Several recent reviews on low-back pain have noted that in most cases acute low-back pain gets better in several weeks, no matter what treatment is used.^8-10 Often, the cause of back pain is unknown, and it varies greatly in terms of how people experience it and how professionals diagnose it.¹¹ This makes back pain challenging to study.

What Kind of Training Do Chiropractors Receive?

Chiropractic training is a four-year academic program consisting of both classroom and clinical instruction. At least three years of preparatory college work are required for admission to chiropractic schools.^12,13 Students who graduate receive the degree of Doctor of Chiropractic (D.C.) and are eligible to take state licensure board examinations in order to practice. Some schools also offer postgraduate courses, including two- to three-year residency programs in specialized fields.¹⁴

The Council on Chiropractic Education, an agency certified by the U.S. Department of Education, is the accrediting body for chiropractic colleges in the United States.¹⁴

What Do Chiropractors Do in Treating Patients?

If you become a chiropractic patient, during your initial visit the chiropractor will take your health history. He will perform a physical examination, with special emphasis on the spine, and possibly other examinations or tests such as X-rays.¹⁵ If he determines that you are an appropriate candidate for chiropractic therapy, he will develop a treatment plan.

When the chiropractor treats you, he may perform one or more adjustments. An adjustment (also called a manipulation treatment) is a manual therapy, or therapy delivered by the hands. Given mainly to the spine, chiropractic adjustments involve applying a controlled, sudden force to a joint. They are done to increase the range and quality of motion in the area being treated. Other health care professionals — including physical therapists, sports medicine doctors, orthopedists, physical medicine specialists, doctors of osteopathic medicine, doctors of naturopathic medicine and massage therapists — perform various types of manipulation. In the United States, chiropractors perform more than 90 percent of manipulative treatments.¹⁶

Most chiropractors use other treatments in addition to adjustment, such as mobilization, massage and nonmanual treatments.¹

Have Side Effects or Problems Been Reported From Using Chiropractic to Treat Back Pain?

Patients may or may not experience side effects from chiropractic treatment. Effects may include temporary discomfort in parts of the body that were treated, headache or tiredness. These effects tend to be minor and to resolve within one to two days.^7,17

The rate of serious complications from chiropractic has been debated. There have been no organized prospective studies on the number of serious complications. From what is now known, the risk appears to be very low.^14,16,17 It appears to be higher for cervical-spine, or neck, manipulation (e.g., cases of stroke have been reported^18,19). The rare complication of concern from low-back adjustment is cauda equina syndrome, estimated to occur once per millions of treatments (the number of millions varies; one study placed it at 100 million¹⁶).^1,20

For your safety, it is important to inform all of your health care providers about any care or treatments that you are using or considering, including chiropractic. This is to help ensure a coordinated course of care.

Does the Government Regulate Chiropractic?

Chiropractic practice is regulated individually by each state and the District of Columbia. Most states require chiropractors to earn continuing education credits to maintain their licenses.^1,13 Chiropractors' scope of practice varies by state — including with regard to laboratory tests or diagnostic procedures, the dispensing or selling of dietary supplements, and the use of other CAM therapies such as acupuncture or homeopathy.^13,14,23 Chiropractors are not licensed in any state to perform major surgery or prescribe drugs.*

Do Health Insurance Plans Pay for Chiropractic Treatment?

Compared with CAM therapies as a whole (few of which are reimbursed), coverage of chiropractic by insurance plans is extensive. As of 2002, more than 50 percent of health maintenance organizations (HMOs), more than 75 percent of private health care plans and all state workers' compensation systems covered chiropractic treatment.¹ Chiropractors can bill Medicare, and more than two dozen states cover chiropractic treatment under Medicaid.²³

If you have health insurance, check whether chiropractic care is covered before you seek treatment. Your plan may require care to be approved in advance, limit the number of visits covered and/or require that you use chiropractors within its network.

What Has Scientific Research Found Out About Whether Chiropractic Works for Low-Back Pain?

For this article, the results of individual clinical trials and reviews of groups of clinical trials were examined. Sources were drawn from the National Library of Medicine's PubMed database; were published in English; and studied chiropractic techniques that were identified as such (e.g., "chiropractic manipulation") rather than some other forms of "manipulation" or "spinal manipulation therapy" — which, as noted above, may be delivered by certain other health care providers.

So far, the scientific research on chiropractic and low-back pain has focused on if, and how well, chiropractic care helps in relieving pain and other symptoms that people have with low-back pain. This research often compares chiropractic to other treatments.

Research Studies
Appendix I gives detailed findings from seven controlled clinical trials and one prospective observational study of chiropractic treatment for low-back pain published between January 1994 and June 2003.

Summary of the Research Findings
The studies all found at least some benefit to the participants from chiropractic treatment. However, in six of the eight studies, chiropractic and conventional treatments were found to be similar in effectiveness.^22,25-29 One trial found greater improvement in the chiropractic group than in groups receiving either sham manipulation or back school.³⁰ Another trial found treatment at a chiropractic clinic to be more effective than outpatient hospital treatment.³¹

General Reviews, Systematic Reviews and Meta-Analyses
Appendix II lists three reviews of clinical trials on chiropractic treatment for back pain, published between October 1996 and June 2003.

Summary of the Research Findings
Overall, the evidence was seen as weak and less than convincing for the effectiveness of chiropractic for back pain. Specifically, the 1996 systematic review reported that there were major quality problems in the studies analyzed; for example, statistics could not be effectively combined because of missing and poor-quality data. The review concludes that the data "did not provide convincing evidence for the effectiveness of chiropractic."³² The 2003 general review states that since the 1996 systematic review, emerging trial data "have not tended to be encouraging. … The effectiveness of chiropractic spinal manipulation for back pain is thus at best uncertain."³³ The 2003 meta-analysis found spinal manipulation to be more effective than sham therapy but no more or no less effective than other treatments.¹⁰

Several other points are helpful to keep in mind about the research findings. Many clinical trials of chiropractic analyze the effects of chiropractic manipulation alone, but chiropractic practice includes more than manipulation.³⁴ Results of a trial performed in one setting (such as a managed care organization or a chiropractic college) may not completely apply in other settings.^29,35 And, researchers have observed that the placebo effect may be at work in chiropractic care,³⁴ as in other forms of health care.

Are There Scientific Controversies Associated With Chiropractic?

Yes, there are scientific controversies about chiropractic, both inside and outside the profession. For example, within the profession, there have been disagreements about the use of physical therapy techniques, which techniques are most appropriate for certain conditions, and the concept of subluxations. Outside views have questioned the effectiveness of chiropractic treatments, their scientific basis, and the potential risks in subsets of patients (for example, the risks of certain types of adjustments to patients with osteoporosis or risk factors for osteoporosis, compared to patients with healthier bone structures^33,36).

Research studies on chiropractic are ongoing. The results are expected to expand scientific understanding of chiropractic. A key area of research is the basic science of what happens in the body (including its cells and nerves) when specific chiropractic treatments are given.

Is NCCAM Funding Research On Chiropractic?
Yes. For example, recent projects supported by the National Center for Complementary and Alternative Medicine, a part of the National Institutes of Health, include:

• Comparing conventional medical care for acute back pain with an "expanded benefits" package (consisting of conventional care plus a choice of chiropractic, massage or acupuncture)

• Finding out what happens (through measurement) in the lumbar portion of the spine after chiropractic positioning and adjustment

• Evaluating the effects of the speed of spinal adjustment on muscles and nerves

• Studying the effectiveness of chiropractic adjustment for a variety of conditions, including neck pain, chronic pelvic pain and temporomandibular disorders (TMD) in the jaw

National Center for Complementary and Alternative Medicine
NCCAM Clearinghouse
P.O. Box 7923
Gaithersburg, MD 20898-7923
1-888-644-6226 or (301) 519-3153
TTY: 1-866-464-3615
Fax: 1-866-464-3616
Internet: http://nccam.nih.gov
E-mail: info@nccam.nih.gov

National Institute of Arthritis and Musculoskeletal and Skin Diseases
National Institutes of Health
1-877-22-NIAMS or (301) 495-4484
Internet: www.niams.nih.gov

Agency for Healthcare Research and Quality (AHRQ)
(301) 427-1364
Internet: www.ahrq.gov

CAM on PubMed
Internet: www.nlm.nih.gov/nccam/camonpubmed.html

ClinicalTrials.gov
Internet: www.clinicaltrials.gov

The Cochrane Library
Internet: www.cochrane.org/reviews/clibintro.htm

References

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Appendix I

Research Studies of Chiropractic Treatment in Adults With Back Pain
Published From January 1994 Through June 2003

** Hurwitz et al. define chiropractic care as "spinal manipulation or another spinal-adjusting technique."

Appendix II

Reviews on Chiropractic Treatment for Back Pain in Adults
Published From October 1996 Through June 2003

***This study on spinal manipulation is included because the authors were able to break down the findings according to the profession of the manipulator, including chiropractors.

Source: National Center for Complementary and Alternative Medicine, National Institutes of Health

Updated: April 16, 2007