Chiropractic ("kye-roh-PRAC-tic") 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 are also 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 Research Report 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. Terms that are linked are defined in the "Definitions" section of this report.
What is chiropractic?
What is conventional medicine?
What is complementary and alternative medicine (CAM)?
The basic concepts of chiropractic can be described as follows:
What is the history of the discovery and use of chiropractic?
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?
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 typically includes12:
Coursework in anatomy, physiology, microbiology, biochemistry, pathology, nutrition, public health, and many other subjects
The principles and practice of chiropractic
Research methods and procedures
Direct experience in caring for patients
What do chiropractors do in treating patients?
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 over 90 percent of manipulative treatments.16
Most chiropractors use other treatments in addition to adjustment, such as mobilization, massage, and nonmanual treatments (see examples in the box).1
Examples of Nonmanual Chiropractic Treatments1
Heat and ice
Have side effects or problems been reported from using chiropractic to treat back pain?
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 reported18,19). 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,a
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 (to find out more, see the NCCAM fact sheet "Selecting a Complementary and Alternative Medicine Practitioner").
aMore information on the topic of complications can be found in references 1-3, 14, 21, and 22, and in scientific databases such as CAM on PubMed (see "For More Information").
Does the government regulate chiropractic?
bIn Oregon, chiropractors can become certified to perform minor surgery (such as stitching cuts) and to deliver children by natural childbirth.14,23,24
Do health insurance plans pay for chiropractic treatment?
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 (read more in the NCCAM fact sheet "Consumer Financial Issues in Complementary and Alternative Medicine").
What has scientific research found out about whether chiropractic works for low-back pain?
A clinical trial is a research study in which a treatment or therapy is tested in people to see whether it is safe and effective. Clinical trials are a key part of the process in finding out which treatments work, which do not, and why. Clinical trial results also contribute new knowledge about diseases and medical conditions. To find out more, see NCCAM's fact sheet "About Clinical Trials and Complementary and Alternative Medicine."
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.
Summary of the research findings
General reviews, systematic reviews, and meta-analyses
Summary of the research findings
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 (see Question 5).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.
This fact sheet often uses the term "adjustment" to refer to chiropractic manipulation. In Question 9 and Appendices I and II, "manipulation" is used where it is used in the source(s) on chiropractic being discussed.
Are there scientific controversies associated with chiropractic?
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?
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
For More Information
The NCCAM Clearinghouse provides information on CAM and on NCCAM. Services include fact sheets, other publications, and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
NIAMS supports research into the causes, treatment, and prevention of arthritis and musculoskeletal and skin diseases; training of scientists; and information based on research. Publications are available.
Agency for Healthcare Research and Quality (AHRQ)
AHRQ is the health services research arm of the Department of Health and Human Services. Publications that may be of interest include Chiropractic in the United States: Training, Practice, and Research (1998) and AHRQ's Clinical Practice Guideline No. 14: Acute Low-Back Problems in Adults (1994; however, this document has been archived by AHRQ and is not considered current clinical guidance).
CAM on PubMed
Web site: www.nlm.nih.gov/nccam/camonpubmed.html
CAM on PubMed, a database on the Internet developed jointly by NCCAM and the National Library of Medicine, offers citations to (and in most cases, brief summaries of) articles on CAM in scientifically based, peer-reviewed journals. CAM on PubMed also links to many publisher Web sites, which may offer the full text of articles.
Web site: www.clinicaltrials.gov
ClinicalTrials.gov is a database of information on clinical trials, primarily in the United States and Canada, for a wide range of diseases and conditions. It is sponsored by the National Institutes of Health and the U.S. Food and Drug Administration.
The Cochrane Library
The Cochrane Library is a collection of science-based reviews from the Cochrane Collaboration, an international nonprofit organization that seeks to provide "up-to-date, accurate information about the effects of health care." Its authors analyze the results of rigorous clinical trials on a given topic and prepare systematic reviews. Abstracts (brief summaries) of these reviews can be read online without charge. You can search by treatment name or medical condition. Subscriptions to the full text are offered at a fee and are carried by some libraries.
Acute pain: Pain that has lasted a short time (e.g., less than 3 weeks) or is severe.
Alternative medical system: A medical system built upon a complete system of theory and practice; these systems have often evolved apart from and earlier than the conventional medical approach used in the United States. An example from a Western culture is naturopathic medicine; from a non-Western culture, traditional Chinese medicine.
Bonesetter: A health care practitioner (not necessarily a licensed physician) whose occupation is setting fractured or dislocated bones.
Cauda equina syndrome: A syndrome that occurs when the nerves of the cauda equina (a bundle of spinal nerves extending beyond the end of the spinal cord) are compressed and damaged. Symptoms include leg weakness; loss of bowel, bladder, and/or sexual functions; and changes in sensation around the rectum or genitalia.
Chronic pain: Pain that has lasted a long time (more than 3 months).
Clinical trial: A clinical trial is a research study in which a treatment or therapy is tested in people to see whether it is safe and effective. Clinical trials are a key part of the process in finding out which treatments work, which do not, and why. Clinical trial results also contribute new knowledge about diseases and medical conditions.
Complication: A secondary disease or condition that develops in the course of a primary disease or condition, or as the result of a treatment.
Controlled clinical trial: A clinical study that includes a comparison (control) group. The comparison group receives a placebo, another treatment, or no treatment at all.
General review: An analysis in which information from various studies is summarized and evaluated; conclusions are made based on this evidence.
Hippocrates: A Greek physician born in 460 B.C. who became known as the founder of Western medicine.
Homeopathy: Also known as homeopathic medicine. It is an alternative medical system that was invented in Germany. In homeopathic treatment, there is a belief that "like cures like," meaning that small, highly diluted quantities of medicinal substances are given to cure symptoms, when the same substances given at higher or more concentrated doses would actually cause those symptoms.
Manipulation: Passive joint movement beyond the normal range of motion. The term adjustment is preferred in chiropractic.
Massage: A therapy in which muscle and connective tissue are manipulated to enhance function of those tissues and promote relaxation and well-being.
Meta-analysis: A type of research review that uses statistical techniques to analyze results from a collection of individual studies.
Mobilization: A technique, used by chiropractors and other health care professionals, in which a joint is passively moved within its normal range of motion.
Myofascial therapy: A type of physical therapy that uses stretches and massage.
Naturopathic medicine: Also known as naturopathy. It is an alternative medical system in which practitioners work with natural healing forces within the body, with a goal of helping the body heal from disease and attain better health. Practices may include dietary modifications, massage, exercise, acupuncture, minor surgery, and various other interventions.
Observational study: A type of study in which individuals are observed or certain outcomes are measured. No attempt is made to affect the outcome (for example, no treatment is given).
Orthopedist: Doctor of Medicine (M.D.) who is a surgeon specializing in disorders of the musculoskeletal system.
Osteopathic medicine: Also known as osteopathy. It is a form of conventional medicine that, in part, emphasizes diseases arising in the musculoskeletal system. There is an underlying belief that all of the body's systems work together, and disturbances in one system may affect function elsewhere in the body. Most osteopathic physicians practice osteopathic manipulation, a full-body system of hands-on techniques to alleviate pain, restore function, and promote health and well-being.
Osteoporosis: A reduction in the amount of bone mass, which can lead to breaking a bone after a minor injury, such as a fall.
Placebo: Resembles a treatment being studied in a clinical trial, except that the placebo is inactive. One example is a sugar pill. By giving one group of participants a placebo and the other group the active treatment, the researchers can compare how the two groups respond and get a truer picture of the active treatment's effects. In recent years, the definition of placebo has been expanded to include other things that could affect the results of health care, such as how a patient feels about receiving the care and what she expects to happen from it.
Prospective study: A type of research study in which participants are followed over time for the effect(s) of a health care treatment.
Randomized clinical trial: A study in which the participants are assigned by chance to separate groups that compare different treatments; neither the researchers nor the participants can choose which group. Using chance to assign people to groups means that the groups will be similar and that the treatments they receive can be compared objectively. At the time of the trial, it is not known which treatment is best. It is the patient's choice to be in a randomized trial.
Review: See general review, systematic review, or meta-analysis.
Sham: A treatment or device that is a type of placebo. An example would be positioning the patient's body and placing the chiropractor's hands in a way that mimics an actual treatment, but is not a treatment.
Subacute pain: Pain that has lasted somewhat longer than acute pain (for example, more than a few days or weeks) but is not yet chronic pain.
Systematic review: A type of research review in which data from a set of studies on a particular question or topic are collected, analyzed, and critically reviewed.