Chiropractic involves hands-on manipulation of the spine and other structures to restore and maintain proper neurophysiological functioning and biomechanical relationships among the vertebra, spinal cord, nerves, and adjacent muscles, joints and bones. Chiropractors also use other conservative management techniques such as patient education, nutritional and self-care recommendations, exercise regimens, physical therapy and rehabilitation.
Manipulation of the spine has been a part of the healing repertoires of virtually all traditional cultures from the ancient Greeks to the Pacific islanders to the Native Americans. The modern practice of chiropractic was introduced in 1895 by a lay healer, Daniel David Palmer, when he performed a spinal manipulation on a man who had been deaf for seventeen years since suffering an apparent misalignment of the vertebra in his upper spine. Palmer applied a sharp thrust, repositioning the bone, and the man’s hearing fully returned. Palmer went on to develop his theory of joint-oriented nerve interference, which he called "chiropractic" by combining the Greek "cheir" (hand) and "praxis" (practice). The first chiropractic college was formed by Palmer in 1897 and the first state licensing law was passed in 1913.
Today chiropractors are the second largest group of primary care providers in the U.S. after physicians, with over 45,000 practitioners. They receive two-thirds of all health care visits for back pain.1
As with other medical professions, chiropractic has evolved in both theory and practice. However, its core principles have remained constant: influencing function through structure. Chiropractors work primarily with musculoskeletal conditions and attempt to restore proper function and to relieve symptoms. Rather than using surgery or drugs, chiropractors use manual procedures and other conservative interventions. Although there is debate within the chiropractic community, most still refer to and treat vertebral "subluxations," a condition where one or more of the bones of the spine are misaligned, interfering with nerve transmission and causing symptoms. Subluxations can cause or perpetuate degenerative and inflammatory conditions, and chiropractors attempt, through manipulation, to correct and maintain the correction of these subluxations.
In a research summary prepared in 1997 for the federal Agency for Health Care Policy and Research, Robert D. Mootz, D.C., and Reed B. Phillips, D.C., describe two core chiropractic principles:
A chiropractic perspective on health and disease emphasizes two fundamental characteristics: 1) a testable principle suggesting that the structure and condition of the body influences how the body functions and heals and, 2) an untestable metaphor that asserts that the mind-body relationship is instrumental in maintaining health and in the healing process.3
The American Chiropractic Association defines the practice of chiropractic more broadly:
Chiropractic is a branch of the healing arts which is concerned with human health and disease processes. Doctors of Chiropractic are physicians who consider man as an integrated being and give special attention to the physiological and biochemical aspects including structural, spinal, musculoskeletal, neurological, vascular, nutritional, emotional and environmental relationships.
The practice and procedures which may be employed by Doctors of Chiropractic are based on the academic and clinical training received in and through accredited chiropractic colleges and include, but are not limited to, the use of current diagnostic and therapeutic procedures. Such procedures specifically include the adjustment and manipulation of the articulations and adjacent tissues of the human body, particularly of the spinal column. Included is the treatment of intersegmental aberrations for alleviation of related functional disorders.2
Clinical studies of chiropractic have reported benefits for a variety of musculoskeletal ailments, but by far the largest body of research concerns back and spinal disorders. For example, one study of 741 patients compared chiropractic to conventional medicine, mobilization or manipulation techniques. Chiropractic was found more effective than the conventional treatment, and its advantages were most striking for patients suffering from chronic low back pain.4
Chiropractic received an important endorsement in 1994 when the National Institutes of Health’s Agency for Health Care Policy and Research published the results of a panel to develop guidelines for treatment of acute low back problems. Based on the available research, the panel recommended chiropractic manipulation within a month of onset of acute low back pain.5
What Are the Potential Uses of Chiropractic?
The greatest strength of chiropractic is in treatment of neuromusculoskeletal conditions such as sprain or strain-type injuries of the back and adjacent structures. Conditions which potentially benefit from chiropractic include:
Low back pain
Mid and upper back pain
Neck pain/stiffness conditions, including torticollis (a twisting of the head to one side that results in abnormal carriage of the head)
In addition, conditions not directly related to the spine but still treated by some chiropractors include problems with knees, wrists, elbows, ankles, and other joints.
Who Practices Chiropractic and What Training is Necessary?
Chiropractors are licensed in every state. They must graduate from a college accredited by the Council on Chiropractic Education and pass four examinations with the National Board of Chiropractic Examiners. Next, if the state in which they desire to practice requires it, they take their individual state board exam. Finally, most states require a certain number of continuing education hours each year.
Chiropractic education requires four years of full-time study, with a minimum of 4200 hours of course work. Many of the textbooks are the same as those used in conventional medical schools. The curriculum includes anatomy, biochemistry, physiology, microbiology, pathology, public health, physical, clinical and laboratory diagnosis, gynecology, obstetrics, pediatrics, geriatrics, dermatology, otolaryngology, roentgenology (x-ray), psychology, dietetics, orthopedics, physical therapy, first aid and emergency medicine, spinal analysis, principles and practice of chiropractic, adjustive techniques, and research methods and procedures.
Is Chiropractic Safe?
The risks of complications or adverse effects arising from chiropractic manipulation are generally regarded as quite low.6 An estimate of the risks was offered in a 1992 review of chiropractic research by a team of researchers from The Rand Corporation, the UCLA Schools of Medicine and Public Health, the Department of Veterans' Affairs Medical Center in West Los Angeles, the Consortium for Chiropractic Research, and Value Health Sciences, Los Angeles. Based on the collective findings of twenty-five controlled clinical trials of lumbar spinal manipulation, the authors concluded that the risk of serious complication following lumbar manipulation could be estimated at less than one case per 100 million manipulations.7
Chiropractic manipulation is contraindicated in cases that involve aneurysm, vertebral artery narrowing, bone tumors, bone infection and fracture.8
What to Expect in a Practitioner’s Office
A practitioner will first take a patient’s history, and then will perform a physical exam. The extent of the exam will depend on the presenting problem, but it usually involves hands-on palpation of the spine to determine its condition. It may also include orthopedic, neurological or physical examination. In some cases, an x-ray may be taken. The patient usually lies or sits on a treatment table for both examinations and treatments.
There are a variety of forms of treatment used, but the primary form involves hands-on manipulation of the musculoskeletal system. This can include all muscles and joints, but the greatest emphasis is on those of the back. Following are descriptions of the main treatments.
Adjustment or manipulation is a high-velocity, low amplitude thrust that lasts about a tenth of a second. The practitioner quickly applies a small, highly controlled force to the body in an effort to restore normal joint motion. Done properly, adjustments are usually painless. There is usually an audible snapping or popping sound, caused by the release of tiny gas bubbles that have built up within the fluid-filled space in the joint, as a result of its immobility.
Electrical stimulation involves introducing an electrical current through a pad placed on an area of the body. The stimulation acts as a form of deep tissue massage, helping move body fluids from the tissue around a sprain to relieve the edema (swelling) that has built up around it.
Ice packs may be used for pain control. Heat packs may be applied to relax muscles and for sedation. Ultrasound is a form of micro-massage that directs sound vibrations into the tissue, stimulates circulation, or helps remove toxins, edema, and electrolytes that have built up around an injury. This is especially useful in "frozen shoulder," bursitis, and tendinitis.
Traction is conducted in a variety of ways to stretch or lengthen the spine and relieve pressure on subluxations (misalignments of vertebrae).
Some chiropractors also use cranial manipulation, the gentle manipulation of the bones of the skull. This may be employed to adjust skull bones or jaw bones that are out of alignment, or to influence the circulation of cerebrospinal fluid.
Also included within the scope of chiropractic practice is muscle therapy (massage), and exercise and nutrition counseling.
William Collinge, Ph.D., M.P.H. and David S. McWaters, Pharm.D., J.D.
1. Shekelle P et al. The Appropriateness of Spinal Manipulation for Low-Back Pain, Project Overview and Literature Review. Santa Monica, VA: Rand Publication R-4025/2-CCR/FCER, 1991
3. Chiropractic in the United States: Training, Practice, and Research. Research Summary. Agency for Health Care Policy and Research, Rockville, MD. AHCPR Publication No. 98-N002, December, 1997.
4. Meade TW; Dyer S; Browne W et al. Low back pain of mechanical origin: randomised comparison of chiropractic and hospital outpatient treatment. British Medical Journal, 300(6737):1431-7 1990 Jun 2
5. Agency for Health Care Policy and Research, Public Health Service. Acute Low Back Problems in Adults. Guideline No.14. U.S. Department of Health and Human Services, 1994
6. Gatterman M. Contraindications and complications of spinal manipulative therapy. ACA J Chiro 18:S75-S86 1981
7. Shekelle P; Adams A; Chassin M et al. Spinal manipulation for low-back pain. Annals of Internal Medicine, 117(7):590-8 1992
8. Gatterman M. Chapter 4: Complications of and contraindications to spinal manipulative therapy. In: Gatterman M, ed. Chiropractic Management of Spine-Related Disorders. Baltimore: Williams & Wilkins, 1990:55-9