Complementary and Alternative Medicine (CAM):
Module 11: Chiropractic
Chiropractic is a hundred-year-old health profession that was developed in the United States as an alternative to the medical practices of the late nineteenth century. Central to chiropractic is the belief that the body has an inherent ability to heal itself, if nerve impulses are allowed to travel freely between the brain and the rest of the body. Manipulation of the spine is the primary means by which chiropractic is believed to free up the functioning of the nervous system. Chiropractors make up the third largest group of health care providers in the United States. As of 1998, the National Institutes of Health National Center for Complementary and Alternative Medicine has funded an eleventh research center with a focus on chiropractic. Under the direction of Dr. William C. Meeker, Director of Research at the Palmer Center for Chiropractic Research, the Consortial Center for Chiropractic Research is charged with establishing the gold standard for future, evidence based, chiropractic research and practice.
A survey conducted by the American Chiropractic Association (ACA) in 2000, lends insight into the current picture of doctors of chiropractics' practice characteristics, patient base, revenue, and referral patterns, as well as the impact of managed care on the profession. The survey, published in the February issue of the Journal of the American Chiropractic Association, polled a random sample of 4000 ACA members and 1000 non-members.
Results from the ACA survey indicate that the majority of chiropractors currently participate in managed care programs. Fifty-nine percent of respondents report that managed care has decreased the average frequency of patient contact. While only 24 percent report that managed care had decreased the average amount of time spent with patients, 41 percent maintain that managed care has decreased the quality of care that they deliver to patients.
Doctors of chiropractic medicine conducted an average of 115 patient visits per Module, with an average of 69 individual patients comprising the visits. The majority of patients were female (58 percent) and in the 17-44 age group (37 percent). Approximately 12 percent of patients were younger than 16 years, and 18 percent older than 65 years. Most patients presented with neuromusculoskeletal conditions including low back pain (43 percent), neck pain (33 percent), and headache (15.4 percent). Treatment was primarily spinal manipulative therapies/adjustments (96 percent) and adjunct physiotherapeutics (56 percent) as well as soft-tissue massage (47 percent). More than 23 percent of patients received nutritional counseling, and approximately 5 percent were treated with either acupuncture or homeopathy in the chiropractor's office.
Doctors of chiropractic medicine referred 27 percent of patients to other
providers including 16 percent to medical doctors, 2.7 percent to physical
therapists, and 3.7 percent to alternative medicine practitioners. Less
than one percent of the survey's respondents were employed by a hospital
or HMO and only 7 percent reported having hospital privileges.
Spinal manipulation has been practiced throughout history to treat muscle and joint pain. The ancient Chinese and the Greeks of Hippocrates' time had methods for manipulating the spine and extremities. Native Americans and Pacific Islanders knew the value of walking on, pummeling, and squeezing an aching back for pain relief.
Although spinal manipulation and manual therapies have been practiced throughout recorded history and in virtually all cultures, chiropractic as a profession which focuses on this form of treatment is only 100 years old. The organization of what was essentially an apprenticeship of bone-setters, lay practitioners, and maverick medical physicians into the profession of chiropractic is credited to Daniel David Palmer, a magnetic healer, who claimed his first official chiropractic spinal adjustment in 1895, and opened the first chiropractic school in Davenport, Iowa.
Over the subsequent 100 years, chiropractic has become an organized profession with licensure in every state and accredited education standards. The debate has shifted from discussion concerning the validity of chiropractic as a health care profession, to a debate whether chiropractic should now be considered mainline health care or alternative health care. The World Federation of Chiropractic has representation from 70 countries and there are now colleges of chiropractic in Canada, Australia, multiple European countries, South Africa and Brazil. In most countries outside of the United States, the colleges are associated with government sponsored universities or colleges. In the United States and in many other countries chiropractic services are paid for by Medicare, worker's compensation programs and many private insurers. There is now a pilot program to integrate chiropractic into the United States armed services and it is becoming an increasing benefit offered by major HMO's.
As recently as 1975, a workshop sponsored by the National Institute for Neurological Diseases and Stroke reported that "Specific conclusions cannot be derived for or against either the efficacy of spinal manipulative therapy, or the pathophysiologic foundation from which it is derived." In contrast, recent reports by the RAND Corporation as well as the formerly named Agency for Health Care Policy and Research (AHCPR), now known as the Agency for Health Care Quality (AHRQ) and other government commissions and agencies in Canada and the United Kingdom have included manipulation in a short list of treatment modalities that are considered established as efficacious, for neck and low back pain. One recent government commission in Canada went so far as to recommend chiropractors over other healthcare professionals as the first contact physician for patients with back pain.
The legitimization of chiropractic and its integration into the health care system has been achieved through a professional emphasis on research in an attempt to define the benefits and risks of spinal manipulation using accepted outcome measures. Spinal manipulation is a prime example of how outcome based research can overcome dogma and bias and lead to widespread acceptance of a treatment method.
Chiropractic was founded when in 1895 Daniel David Palmer, a successful self-taught healer in Davenport, Iowa, received a visit from the janitor of his office building who had been deaf for seventeen years following a straining injury. Palmer, who had a background in spinal therapeutics, physiology, anatomy, magnetic healing, and laying on of hands, examined his patient and found a prominent, painful, misaligned vertebra in his upper spine, in the area that the man had injured years before, just before he lost his hearing. Palmer administered a sharp thrust to adjust the bone, and the janitor's hearing was restored. Palmer believed that by adjusting the misaligned vertebra he had relieved pressure on a nerve that affected his hearing.
Palmer christened his new approach chiropractic, meaning "done by
hand," from the Greek words cheir for hand and praxis for practice.
In 1897 he set up a school to teach his system. Palmer's son, Bartlett
Joshua Palmer, had a flair for showmanship and brought the new profession
to prominence, by drawing the hostility of conventional medicine with
numerous inflammatory and antagonistic declarations.
Chiropractic theory as originally formulated by D.D. Palmer is not just a theory of health and illness. It is a belief system based on Palmer's central tenet that all living things are endowed with a life force, which he termed "Innate Intelligence," and that the human organism can keep itself healthy if there are no barriers to the full expression of this life force that regulates all vital functions. Palmer believed that the "innate intelligence" flows through the nervous system to all parts of the body. Because the nervous system and musculoskeletal system are intimately intertwined and interrelated, Palmer held that any distortion of the spine could cause illness in any part of the body supplied by the nerves. He asserted that by manipulating the spine and other joints through which the nervous system passes the chiropractor could remove obstacles to the full expression of the "innate intelligence" and help restore the body to health.
Critics of chiropractic, as cited in a negative Consumer Reports article in 1994, pointed out that in adjusting the spine, chiropractors have access to only part of the nervous system, namely the 26 pairs of nerves that branch out through openings in the vertebrae. Other important nerves, especially the cranial nerves, do not pass through the spine and are therefore inaccessible to spinal manipulation. In fact, even Palmer's historic adjustment of the janitor's spine to restore the man's hearing is debatable. It makes little sense since the nerves that control hearing are located in the skull and are not influenced by the spine. Cervical ganglion of the sympathetic nervous system, which plays a role in vascular perfusion to the ear, has a direct anatomical relation to the cervical spine. Also modern chiropractic theorizes pathways other than through the nervous system that accounts for some chiropractic efficacy.
Critics point out that there is no evidence for or against the assertion that manipulation of the spine can have lasting influence on distant portions of the nervous system and other organs of the body. Chiropractors, on the other hand, argue that there is an intimate relationship between the internal organs and the musculoskeletal system. Dr. William Meeker, Dean of Research at Palmer College of Chiropractic in Davenport, Iowa, has commented that while some people think of the bones and muscles as supporting the heart and lungs, chiropractors see the viscera as serving the musculoskeletal system, ensuring that it works properly, and allowing us to be mobile on the earth. Most of the body, Meeker, observes, is made up of bones, joints, and muscles, not heart, lungs, and gut. Dr. Meeker and his Center represent a more state of the art and contemporary form of chiropractic practice and research which is often far removed from the questionable past practices that elicit very negative criticisms.
In his original formulation of chiropractic theory in 1895, D.D. Palmer coined the term "subluxation" to describe misalignment or partial dislocation of the vertebrae that make up the joints of the spine. According to Palmer, subluxations put undue pressure on the spinal cord or the nerves that exit through the spine, and therefore disturb the normal neurophysiological functioning of the whole person. Because of inappropriate pressure on nerves, or "nerve reflex," caused by subluxations, bodily functions supplied by those nerves are disturbed and make the individual more vulnerable to disease. Illness, according to this theory, results from disturbances in the nervous system arising from derangements in the musculoskeletal structure.
Subluxations can occur in the course of everyday life in any culture, but our modern sedentary lifestyle makes us particularly vulnerable to subluxations because the spine does not receive the amount of daily movement it was evolved for.
Early chiropractors believed that subluxations are the case of all disease.
Today many chiropractors recognize that a great many factors contribute
to health and illness, and that many bodily systems work together to determine
an individual's overall health picture. Many chiropractors today still
believe that subluxations can be a major predisposing factor to illness
because they prevent the nervous system from working at its optimal level.
Their definition of subluxations, however, may be different from the classic
definition; they may use the term more generally to describe any joint
Chiropractic is a drugless and nonsurgical tradition whose primary form of treatment is manipulation of the musculoskeletal system. Manipulation means the application of physical force to bodily tissues, most often joints and muscles, usually delivered by hand, but sometimes in other ways. All muscles and joints can be manipulated, but the greatest emphasis is on those of the back. In addition, chiropractors use exercise and rehabilitation procedures, physical therapy modalities, and lifestyle advice including nutrition, hygiene, and health promotion. A significant proportion of chiropractors also use other modalities such as acupuncture or homeopathy. Nevertheless, spinal manipulation is the core of chiropractic treatment.
Today the term "adjustment" is preferred for chiropractic manipulation of the spine or other joints. Typical chiropractic adjustment is a high-velocity, low-amplitude thrust, which lasts about one-tenth of a second, in which the practitioner applies a small, highly controlled force to stretch a joint just beyond its usual range of motion. The procedure is painless when done properly, and is usually accompanied by an audible snapping or popping sound, resulting from the release of tiny gas bubbles that have built up in the joint fluid because of immobility. Properly done, the adjustment immediately produces an improvement in joint function, with increased range of movement, relief of pain, and relaxation in the area.
Spinal manipulation is not limited to the chiropractic profession. Osteopaths, allopathic doctors, and physical therapists also use it. However, according to a 1994 Rand study chiropractors perform 94 percent of manipulative procedures delivered by health practitioners in the United States.
Applications of manipulative forces can vary greatly in terms of amplitude, velocity, direction, duration, and frequency. Besides the characteristic high-velocity, low-amplitude chiropractic adjustment, there are low-velocity, variable-amplitude maneuvers, often called mobilizations. Other forms of manipulation that chiropractors use may include soft tissue manipulation, trigger point manipulation, or direct deep tissue massage. There are four distinct definitions that are frequently used to characterize manual manipulative methods overall. The term of spinal manipulative therapy is often used to encompass all types of manual techniques regardless of their anatomic focus or their discipline of origin. Mobilization is defined as passive movement of a joint within its physiologic range of motion. This roughly equates to the range of motion for a normal joint. Manipulation is passive joint movement, which takes the joint beyond its physiologic range into the "paraphysiologic" space where muscle contraction alone does not usually move a joint as far. When a joint is moved into this range, cavitation can occur which, in a synovial joint, is typified by an audible release or "pop", due to a gaseous bubble which may appear within the synovial fluid for several minutes after manipulation.
Chiropractors also use a variety of external treatments to help
relax muscle tension before making a manual adjustment, or to support
the body's healing by keeping the musculoskeletal system in its optimal
condition. Among the forms of physiotherapy that may be used by some chiropractors
are the following:
In addition, physical therapy exercises or individual exercise may be performed actively by the patient, or may be performed by the therapist on the patient. Such exercises are used to improve muscle tone, flexibility, and circulation of blood and lymph, and to prevent joint adhesions and fixations.
Postural guidelines, lifestyle counseling, and referral to educational programs or to psychotherapy to support lifestyle changes, may all be employed by chiropractors as follow-up care.
Chiropractors employ a number of variations on the basic chiropractic manipulative techniques. There are many unique features associated with chiropractic techniques including patient positioning, equipment, characteristics of pre-stressing joints and thrust.
In 1991, Bartol categorized chiropractic adjustive techniques according to their mechanical characteristics. A classification scheme used by many American and Canadian chiropractic practices distinguishes six major categories of manual articular and manual non-articular adjustments with as many as 13 subcategories. A 1993 book entitled, Guidelines for Chiropractic Quality Assurance and Practice Parameters by Haldeman and colleagues, lists upwards of 16 different, specific chiropractic techniques. Among some of these distinctions are the following:
Cranial manipulation focuses on the bones of the skull and the spinal fluid, which moves in pulse-like waves in the skull and spinal column. A chiropractor, Dr. Major B. DeJarnette, coined the terms craniopathy and sacro-occipital technique for his variations of cranial manipulation, which he learned from the osteopath Dr. William Sutherland, who developed cranial osteopathy in the 1930s.
Sacro-Occipital Technique (SOT) emphasizes the relationship of
the cranial bones and the bones of the pelvis and lower back. First, the
cranium and sacrum are adjusted based on the theory that any spinal subluxation
is a compensation for an imbalance in either the cranium or the sacrum,
or both. Once these adjustments are made, then other subluxations that
have not naturally balanced themselves are adjusted.
Activator technique, also known as nonforce adjustment, employs a small rubber-tipped instrument called an activator that is used to move the vertebrae gently and painlessly. This technique can be used along with or in place of manual adjustments.
In 1979, Network Chiropractic was developed by Dr. Donald Epstein, D.C. beginning in 1979. This is a unified system of twelve chiropractic techniques that pays special attention to their timing and works with the postulated "Innate Intelligence" of the patient. It uses light, subtle touch, combining a variety of chiropractic techniques to adjust subluxations with the precise amount and type of force suggested by clinical findings. According to Dr. Epstein, the key to this approach is the sequence of the adjustments and the networking of the various methods.
Historically, a heated philosophical debate among chiropractors has split the profession into two schools of thought, often described as the "straights," or conservatives, and the "mixers," also known as liberals. This debate has subsided in recent years but echoes of it remain in the profession.
Straight chiropractors adhere to pure chiropractic theory and limit their practice to the diagnosis and correction of subluxations to improve health through the manual manipulation of the spine. A minority, about 15 percent of chiropractors consider themselves straight practitioners today. A 1992 International Straight Chiropractic Consensus Conference summarized their approach as a "limited, primary health care profession," with responsibility "limited to the anatomy of the spine and immediate articulations, the condition of vertebral subluxation, and a scope of practice which encompasses addressing vertebral subluxations as well as educating patients and advising them about subluxations." Straight chiropractors avoid using terms employed by other health professions. Instead of "diagnosis" they say "analysis," and instead of "manipulation" they say "adjustment." Straights tend to use x-rays as a major diagnostic tool to assess skeletal misalignments.
"Mixer" is a term coined by advocates of straight chiropractic to refer to chiropractors who use a variety of natural health care therapies including heat, cold, ultrasound, electrical stimulation, massage, exercise, and nutrition in support of their adjustment therapy. Their practice extends beyond the narrow focus of vertebral subluxation, and they use a wide range of modalities and concepts from diverse health care traditions. Mixers constitute the majority of chiropractic practitioners today.
Some mixer chiropractors' practices have moved entirely away from the traditional focus on treating subluxations and toward a greater emphasis on another tradition. Because they are licensed as primary care providers, they are free to use other modalities as they choose. One of the most common adjuncts used by mixers is nutritional supplementation. They may also integrate Chinese medicine, Ayurveda, naturopathy, homeopathy, massage, bodywork, mind-body approaches, or other healing methods. Mixers may also use variations on manipulation such as craniopathy, applied kinesiology, activator technique, or bioelectrical therapy.
Related to the distinction between the straights and the mixers is a distinction between subluxation-based and medically-oriented chiropractic. Subluxation-based chiropractors use spinal adjustment as the focus of their practice, whether or not they employ other modalities from other traditions. They adhere to the principle of "innate intelligence" as the key factor in healing. According to the World Chiropractic Alliance, about 20 percent of the chiropractic profession now belongs to the growing number whose approach is becoming more allopathic in terms of diagnosing and treating disease and using allopathic procedures in their practice. Mixer chiropractic schools may train their students in general allopathic diagnosis, including magnetic resonance imaging (MRI), laboratory tests, and CAT scans, as well as chiropractic diagnostic procedures. A variety of specialty board certifications is offered by the American Chiropractic Association; perhaps another reflection of a movement toward greater alignment with allopathic approaches in chiropractic.
Although there remain remnants of this dichotomy, the distinctions among current chiropractic practices are more mixed and complex than the historical continuum. However, these philosophical differences among chiropractors can make a significant difference in the kind of treatment a patient receives. For someone with strictly spinal or skeletal misalignment, a straight chiropractor may have an advantage, since that is the area that he or she will address, but the straight practitioner will not diagnose or treat other problems. Mixers, on the other hand, may address a wide range of illnesses, employing a variety of modalities, although they may not necessarily have the specific training and qualifications to do so.
Nutritional counseling and muscle testing are two separate clinical services provided by some chiropractic practitioners. Chiropractors are legally permitted to provide nutritional advice, and many recommend vitamin and mineral supplements to correct deficiencies that may contribute to dysfunction in the neuromusculoskeletal system or other organs.
Seventy-four percent of some 2400 chiropractors surveyed by a leading chiropractic newspaper in 1988 reported that they used nutritional supplements in their practice. As reported in a 1994 Consumer Reports article, in a National Board of Chiropractic Examiners (NBCE) survey, 84 percent of responding chiropractors said they had provided nutritional counseling, treatment, or supplements within the last two years. Many supplement companies sell their products exclusively through chiropractic offices, and some critics argue that these supplements are overpriced and may not be helpful.
Applied Kinesiology (AK), is a system for diagnosing and treating illness based on the belief that every organ dysfunction is accompanied by a specific muscle weakness. The technique is based on the theory that complementary muscles can indicate the strength or weakness of the other muscles as well as corresponding organ systems. Skilled practitioners say they can use AK to test organ systems and determine whether a supplement is effective and at what dosage. In the NBCE survey, 37 percent of chiropractors surveyed said that they used AK.
Many critics argue that such unorthodox approaches as AK and some forms of nutritional counseling go beyond the appropriate scope of chiropractic practice, and that chiropractors would do better to confine their activities to the use of manipulative techniques, which have traditionally been the core of their practice.
An initial visit with a chiropractor begins with a discussion of the patient's history, with particular attention to the current problem and symptoms. Chiropractors are trained to do a standard physical examination, although state laws vary as to whether the physical exams are acceptable for legal purposes. In addition to the standard physical, the chiropractor observes how the patient walks, bends, and sits. The chiropractor conducts a posture analysis, and palpates the spine to determine whether there are any muscle imbalances or subluxations. After the case has been assessed for appropriateness, a treatment plan is devised.
Chiropractic treatment usually involves a series of visits. In an uncomplicated low back condition, improvement should be noted within twelve visits. If a disc is bulging or protruding, it may take longer, but there should be some substantial change within twelve visits. In addition to the treatment of acute problems, some chiropractors advocate aligning the spine on a regular basis as a preventive measure in order to keep it free from subluxations.
In the past chiropractors commonly took full spine x-rays, often repeatedly, to locate and follow the progress of subluxations. Such x-rays are not only expensive, but also unnecessarily expose the body to excessive levels of harmful radiation, and can rarely be justified for diagnostic purposes. Today few chiropractors insist that x-rays are necessary to show subluxations. Nevertheless, according to a 1991-92 publication of the American Chiropractic Association, nearly 17 percent of x-rays done by chiropractors were still of the full-spine variety.
Most chiropractors today use more focused regional x-rays to
rule out problems that would preclude manipulation such as fracture, structural
anomalies, or cancer that has metastasized to the bone.
An initial chiropractic visit generally takes 45 to 60 minutes, and may cost from $50 to $150 or higher. Costs are generally lower in rural areas. Some practitioners give a free initial consultation. Subsequent treatments may range from $20 to $50 for a 10-25 minute visit. Supplements might cost an additional $10 to $200 or more per visit.
Approximately 75 percent of insurance companies, including Medicare,
pay for chiropractic care, and workers compensation plans in all states
cover chiropractic treatment. In 1997, New York Governor George E. Pataki
signed into law a bill, that for the first time requires health insurance
companies in New York to pay for most services provided by chiropractors.
This new law requires insurance companies and HMOs to pay for up to 15
chiropractic visits each year and this 15-visit cap will end in two years.
Whether or not this new law will increase or decrease the number of patients
seeking chiropractic and resulting medical costs is yet to be determined.
This legislation marks a significant step in the recognition of, and access
to chiropractic care in a bellwether state.
Chiropractic's greatest strength is in the treatment of neuromusculoskeletal conditions, such as sprains or strains of the back and related structures. Such problems account for more than 90 percent of the chiropractic caseload.
Back pain is second only to the common cold as a reason for visits to doctors' offices and second only to childbirth as a reason for hospitalization. Current estimates are that chiropractors treat about 40 percent of patients seeking care for low back pain in the United States. Other conditions for which patients commonly seek chiropractic care include upper back, neck, and head pain, and extremity, joint, and muscle problems.
A much smaller proportion of patients seek chiropractic care for non-musculoskeletal conditions, often of a chronic or visceral nature. According to chiropractic theory, chiropractic manipulation has a general health-enhancing effect, and there exist clinical anecdotes and case reports that support this point of view. According to chiropractor Dr. Chester Wilk of Chicago, who has written several books on the subject, chiropractic care has been successful in treating such non-musculoskeletal ailments as respiratory problems, gastrointestinal disorders, sinusitis, bronchial asthma, heart trouble, high blood pressure, and the common cold.
In its highly critical survey of chiropractic in 1994, Consumer Reports cited pro-chiropractic advertising and patient-education materials indicating that chiropractors were prepared to take on all sorts of medical problems. Pamphlets with titles such as "Heart Disease and Chiropractic," "Prostate, Impotency, and Chiropractic," "Allergies and Chiropractic," "Seizures, Epilepsy, and Chiropractic" are sold to chiropractors for educating their patients. According to Consumer Reports, these pamphlets are "filled with misinformation about standard medical care," and promote the traditional chiropractic belief that correcting spinal misalignments helps the body heal itself.
The American College of Addictionology and Compulsive Disorders (ACACD) in Miami has chosen chiropractic as the profession of choice for board certification in Addictionology. Chiropractic is favored because it is a drugless approach, and chemically dependent people need to avoid mood-altering substances throughout their lives in a manner consistent with accepted medical care as well as variants of the Alcoholics Anonymous model.
Children have been another focus of chiropractic outreach, a trend which is alarming to critics of the profession as well as many within chiropractic medicine. Approximately ten percent of chiropractic patients, or as many as two million, are 17 or younger. However, according to Dr. Meeker in 1997, patients younger than 18 do not comprise such a large percentage of chiropractic practices. Childhood problems such as otitis media and asthma comprise less than 1% of reported diagnoses. In some states the profession is conducting campaigns to convince schools and parents that correct posture, maintained through regular chiropractic treatment, contributes to overall health in youngsters. Chiropractors have also claimed success in treating such childhood problems as epilepsy, asthma, bedwetting, and learning disabilities.
One reason that critics oppose chiropractic care for children is that the profession has historically been opposed to immunization. It wasn't until 1993 that the American Chiropractic Association came out in support of routine childhood vaccinations. The World Chiropractic Alliance, a small traditional group, continues to oppose mandatory immunization through a public information campaign. As far as more mainstream chiropractic, this stance is not supported. In fact there is a Chiropractic Health Section of the American Public Health Association, which explicitly endorses immunizations, as well as a host of other positive public health measures such as smoking cessation.
Chiropractors do not prescribe medications, perform major surgery, or treat fractures. They cannot provide emergency care or deal with life-threatening illnesses. While all chiropractors are trained in obstetrics and gynecology and can deliver babies, most states limit their ability to do so. Fewer than half a dozen chiropractors still deliver babies in the United States with the most in Oregon. Rural states tend to allow a wider scope of practice.
There are few published reports of serious complications arising from spinal manipulation, but such complications may be underreported since complications are often not adequately documented in most clinical practices whether conventional or chiropractic. In 1993, a survey of literature reported in the journal Neurosurgery found 138 cases of complications in English-language journals, all the reports coming from conventional physicians who had been called in to treat the problem. They found only 112 published case reports of complications due to neck manipulation over a period of some 65 years. Documented risks of chiropractic manipulation range from increased pain to ruptured disks, and paralysis. Manipulation of the neck tends to produce the most serious injuries such as stroke or other neurological problems.
Chiropractors have among the lowest malpractice insurance premiums of
all physician specialties, and the percentage of chiropractic physicians
who have been sued for malpractice is lower than the percentages of medical
and legal professionals, according to Brady in 1994 and the Medical Liability
Monitor in 1996. Malpractice premiums do not necessarily provide an accurate
measure of risk, they do reflect the relative number and severity of complications
and problems arising from care. Overall, chiropractic procedures appear
to be comparatively safe, although potential side effects, complications,
and contraindications to adjusting have been identified. Claims data from
Canada revealed that between January 1986 and December 1990, there were
a total of 159 claims made against chiropractors with the most common
complaints being for lumbar spine injury, rib fracture, soft tissue injury,
and cervical spine injury. Cerebrovascular accidents accounted for 6-8%
of the claims in the early 1990s. According to claims data from the National
Chiropractic Mutual Insurance Company for 1990, the most common cause
of malpractice claims were for disc problems, failure to diagnose, fracture,
and soft tissue injury.
Another major contraindication is progressive neurological deficit. A delay in diagnosis in patients who are deteriorating is a contraindication to manipulation, or, for that matter any treatment except emergency care. In the same light a marked and sustained response to a similar form of manipulation in the past would constitute a contraindication, as is the case in any treatment until further investigation is undertaken. Patients, however, can experience transient increase in symptoms that can last up to 48 hours, which do not contraindicate further manipulation.
Chiropractic textbooks clearly describe the contraindications to spinal manipulation, and they are an important part of chiropractic practice guidelines. Occasionally in the case of undiagnosed cancer, for example, chiropractic adjustment could be harmful if the patient goes to a chiropractor with back or neck pain from an undiagnosed metastasis to the spine.
Spinal manipulation is also not recommended in the presence of such problems as fractures, rheumatoid arthritis, severe osteoporosis, bleeding disorders, infection or inflammation of the spine. Manipulation of the neck can be relatively risky, especially if the patient is taking oral contraceptives or blood-thinning medications, or has high blood pressure or other risk factors for stroke.
Another risk cited in the 1994 Consumer Reports, that may attend chiropractic care is that it may keep some patients from seeking appropriate medical treatment in a timely manner. While it is not known how often this may happen, there exist reports of patients receiving inappropriate chiropractic treatment for serious medical problems. In 1992, according to The Journal of Pediatrics doctors at a Wisconsin clinic reported 18 children who received chiropractic treatment for problems including cancer, diabetes, kidney disease, and school phobia.
Another concern among some critics is the profession's antipathy to prescription drugs, and the fear that chiropractors may try to use manipulation where medication might be more appropriate.
Manipulation of the cervical spine, for the purpose of relieving neck and back pain and increasing range of motion, although generally considered safe, has raised concerns in the medical community. Reports of complications range from discomfort to brainstem lesions, stroke, and death. Few systematic efforts have been made to document injuries or to understand their cause so that they might be prevented in the future. One manipulation that is associated with the most serious complications is rotational movement of the upper body.
In 2001 two studies on the safety of spinal manipulation (SM) suggested that concerns about adverse outcomes associated with this therapy may be warranted. Reporting in the Journal of Pain and Symptom Management, Ernst conducted a systematic literature review of all prospective investigations into the safety of SM. Five prospective studies were found that used either mailed questionnaires, or interviews to collect data. Results indicated that as many as half of those treated with SM experienced adverse reactions, mostly of a mild and transient nature. While mild effects were frequent, the rate of serious adverse effects could not be evaluated based on fragmentary data. "The remarkable popularity of SM is contrasted by a disappointing lack of prospective investigations into its safety." Ernst concluded that considering the high degree of regularity with which case reports of serious adverse events of SM continue to be reported, this seems to constitute a serious omission of research.
A survey published in the Journal of the Royal Society of Medicine, also
concludes that "concern about neurological complications following
cervical spine manipulation appears to be justified." All 323 members
of the U.K. Association of British Neurologists were asked to report cases
referred to them, pertaining to neurological complications occurring within
24 hours of cervical spine manipulation in a 12-month period. Responses
from 239 members (79 percent) reported 35 cases of serious complications,
including stroke, myelopathy, and cervical radiculopathy-an underestimate,
the investigators believe. Dr. C. Stevinson concluded that although a
precise estimate of the incidence is not possible from current data, there
is sufficient information to suggest that the subject requires direct
Historically chiropractic has not had an adequate basis in scientific and academic research. Effectiveness of chiropractic treatment has generally been evaluated on the basis of the subjective experience of the patient and the judgment of the practitioner.
In recent years the chiropractic profession has attempted to respond to increasing demands for scientific evidence of the efficacy and cost-effectiveness of its treatment by undertaking a number of research efforts. One result was the establishment in 1985 of the Consortium for Chiropractic Research, a nonprofit organization made up of 26 chiropractic colleges, professional associations, and insurance companies which, along with the American Chiropractic Association's Foundation for Chiropractic Education and Research, has taken a lead in attempting to document a scientific basis for chiropractic. Research is currently under way at chiropractic schools to study the effects of chiropractic care on a variety of conditions.
The strongest chiropractic research is in the treatment of low back pain, and in studies of patient satisfaction and cost-effectiveness. The emphasis in the following discussion will be on studies evaluating outcomes of care that used randomized clinical trial designs, but other study designs will also be referred to as needed. Research to be discussed focuses on the outcome of spinal manipulation, which constitutes the core of chiropractic treatment. Some chiropractors use other therapies as well, but these would need to be evaluated separately.
There are more than 30 randomized controlled clinical trials studying the effectiveness of spinal manipulation in the relief of spinal pain, the majority of which have looked at acute low back pain. These studies have been subjected to a number of meta-analyses which have consistently demonstrated a beneficial effect of manipulation on the duration and severity of low back pain. Manipulation has been compared to most non-surgical treatment modalities including placebo, ultrasound, traction, exercise, bed rest, analgesics and corsets.
There are eleven published studies on the effectiveness of manipulation on chronic low back pain. Each of these studies reported short-term positive results in one or more parameters of pain disability. There is a smaller number of studies on the effectiveness of manipulation in patients with sciatica and/or radiculopathy. The quality of these studies tends to be less than those for acute low back pain and the results are more variable. Furthermore, the long term studies suggest that a short-term period of manipulation probably does not have substantial long term effects on pain.
There are a growing number of randomized controlled clinical trials on patients with neck pain and headaches, most of which show a beneficial effect, although a few studies show no difference from controls. A 1996 meta-analysis by Hurwitz and colleagues suggested that there was a modest improvement following manipulation. There are no studies on the effectiveness of manipulation in patients with cervical radiculopathy.
In the past 5 years, spinal manipulation has been the focus of evidence-based literature syntheses and meta-analyses performed by both medical and chiropractic researchers. A formal meta-analysis of the literature in 1992 concluded that spinal manipulation was of short-term benefit for patients with uncomplicated acute low back pain, but that there was insufficient evidence for or against manipulation for patients with nerve root pain or chronic back pain. A 1991 blinded systematic literature review by Koes of 35 randomized clinical trials concluded that although the results were promising, the efficacy of manipulation had not yet been convincingly demonstrated. Although only five of the randomized trials involved manipulation by a chiropractor, the findings of these literature syntheses provided some scientific evidence that spinal manipulation is at least as effective for low back pain as most standard medical treatments.
There are at least 36 randomized clinical trials in the clinical literature comparing manipulation to some other form of treatment for various forms of low back pain (LBP), as well as a larger number of observational studies. Twenty-four of the randomized trials favored manipulation, while twelve did not, but in no case was the comparison treatment found to be more effective than manipulation. It should be noted that the most commonly used, conventional treatments for back pain, including muscle relaxants and various forms of physical therapy, lack evidence of research efficacy, largely due to the absence of research into these currently acceptable treatments in widespread use.
These LBP trials can be broken down into acute and chronic categories; chronic includes subacute, and refers to low back pain that has existed for more than six Modules.
Twelve trials evaluated patients with acute LBP. Manipulation was given either as the sole treatment, or in combination with other treatments, and was compared with physical therapy modalities such as exercise, back school, diathermy, infrared, electrical stimulation, and massage, as well as pain-killing drugs in some studies. Six of the studies found better rates of recovery, pain reduction, and improvement in physical functioning with manipulation; three studies found no statistically significant differences between the comparison groups; and three trials found statistically significant differences in a subgroup of the study sample only.
Eight trials focused on patients with chronic or subacute low back pain. Manipulation was given either alone or in combination with other treatments, and was compared with a variety of conservative modalities including physical therapy, bedrest, pain killers, and sham manipulation. Five studies reported better results with manipulation, and two reported no additional benefit from manipulation. One did not draw a statistical conclusion.
Twelve trials included a mixture of acute, subacute, and chronic LBP patients. Eight reported results favoring manipulation, and one reported a favorable result in a subgroup. Eleven of these trials included a comparison with some form of placebo therapy, such as detuned diathermy or sham manipulation. In seven of these studies, manipulation was more effective than the placebo, which appears to argue against the possibility that the effects of manipulation are due to some nonspecific mechanism such as suggestion.
Among the positive reports of chiropractic efficacy is a 1995 study by Meade and colleagues in the British Medical Journal. This study was conducted at the Medical College of St. Bartholomew's Hospital in London and compared the long-term effectiveness of chiropractic versus hospital outpatient management for low back pain.1
Besides the individual randomized studies of treatment of low back pain with manipulation, there are a large number of collective reviews of the original research data. In a paper by Assendelft, published in a 1995 issue of the Journal of the American Medical Association, a group of Dutch epidemiologists from Vrije University in Amsterdam looked at 51 such reviews, of which 34 concluded that the evidence favored spinal manipulation for low back pain, while 17 were neutral. The reviews were coded for quality and scholarship. Nine of the ten highest-rated reviews were in favor of manipulation. Other factors related to a conclusion in favor of manipulation were the inclusion of a manipulator on the study team and a more comprehensive literature review.
One of the most noteworthy of the literature reviews is an analysis of research on spinal manipulation for the treatment of low back pain published in the Annals of Internal Medicine in 1992. These reviews were conducted by a team of researchers at the RAND Corporation in cooperation with the Consortium for Chiropractic Research, the UCLA Schools of Medicine and Public Health, the Department of Veterans Affairs Medical Center in West Los Angeles, and Value Health Sciences of Los Angeles. They evaluated 25 controlled clinical trials of spinal manipulation for low back pain, in a meta-analysis and concluded that, with manipulation there was a 17 percent greater likelihood of recovery from uncomplicated acute low back, within three Modules, than without it. Since the recovery rate without manipulation in these trials is about 50 percent, manipulation increased the probability of recovery in three Modules, by about a third. This study concluded that manipulation hastened recovery from acute low back pain, but for chronic back pain results were insufficient to draw conclusions.
The studies of spinal manipulation surveyed in the RAND review do not necessarily prove or disprove the value of chiropractic adjustments per se. Other practitioners besides chiropractors use spinal manipulation, such as orthopedists, osteopaths, physical therapists, physiatrists, and specially trained physicians. Since a variety of different practitioners applied a wide range of manipulation techniques, it is possible to generalize these findings or to attribute outcome to any one discipline's approach to musculoskeletal manipulation.
A systematic qualitative review by Koes pertaining to spinal manipulation for low back pain was reported in Spine in 1996. For this review, Koes and associates reviewed 36 randomized trials and scored them for quality. They found that eight of the ten best studies favored manipulation.
Despite the weakness of many studies, the existing evidence for the effectiveness of manipulation for treating low back pain is compelling, in light of recent research that has shown that allopathic medicine has little to offer, in the way of conservative treatments, for this very common ailment. In up to 90 percent of cases of uncomplicated back pain, the symptoms subside within two to twelve Modules, whether any treatment is given or not. As noted in the above-cited studies, spinal manipulation is currently one of the few conservative treatments for LBP that has been found in randomized trials to speed recovery. In fact, some widely used allopathic treatments have been demonstrated not to be effective, such as corticosteroid injections and transcutaneous electrical nerve stimulation. Extended bed rest, traction, and corsets are also of little help, according to a study at the University of Washington Schools of Medicine and Public Health, reported in Consumer Reports in 1994.
Existing evidence from clinical trials has been sufficient to cause government-sponsored groups of experts to arrive at the consensus that spinal manipulation should be recommended as a treatment for back pain. After reviewing 4000 studies, the U.S. Agency for Health Care Policy and Research (AHCPR), now known as the Agency for Health Care Quality (AHRQ)) concluded that the expensive tests and treatments used in conventional medicine to treat low back pain are largely useless and possibly harmful. A 1996 government-sponsored study conducted in the United Kingdom by the Clinical Standards Advisory Group also recommended in favor of spinal manipulation.
In October of 1998, Dr. Daniel C. Cherkin and his colleagues at the University of Washington provided new data in a study published in the New England Journal of Medicine. They assigned 321 people with low back pain that had lasted for at least a Module to nine visits with a chiropractor, a similar number of sessions with a physical therapist, or no special treatment other than an educational booklet on back pain. Both the chiropractic and physical therapy groups recovered at the same rate, which was slightly faster than that of the control group. There was no difference among the three groups in terms of missed work, reduced activity, or recurrent episodes of low back pain during the subsequent year.
In summary, there is sufficient published evidence to support the efficacy of spinal manipulation for low back pain, especially within the first three months. While some studies have reported favorable long-term results, the data are insufficient to draw reliable conclusions.
Manipulation of the cervical spine for neck pain and headache has also been evaluated in randomized clinical trials. Evidence for the effectiveness of manipulation for neck pain is still more limited than that for low back pain. However, this fact should be viewed in context: There is a surprising lack of evidence for most treatments of musculoskeletal conditions-even commonly accepted ones. For example, one recent review of conservative therapies for neck pain concluded that the available evidence supports the use of manual therapies in combination with other treatments for short-term relief of neck pain. It also concluded, little or no scientific evidence exists for other therapies, including such commonly used treatments as medication, rest, and exercise.
Few studies have been done to determine which specific neck conditions are most amenable to manipulative treatment. However, anecdotal evidence and consensus documents suggest that uncomplicated acute or subacute neck pain without neurological involvement is most responsive. Manipulation is also often useful in chronic cases of neck stiffness, crepitation, and aching (often diagnosed as osteoarthritis).
The most serious potential complication from cervical manipulation is the possibility of vertebrobasilar stroke. In very rare cases, cervical manipulation may damage the vertebral arteries as they course through the upper cervical vertebrae and into the upper cervical vertebrae and into the base of the brain, resulting in ischemic insult to the brainstem. The best estimate of the risk of a cerebrovascular incident from neck manipulation is about 0.5 to 2.0 per million manipulations (Coulter et al; Dabbs and Lauretti). This risk is significantly less than the risk of gastrointestinal complications.
Contraindications to neck manipulation include the presence of a tumor, fracture, or bone infection in the cervical spine, or severe osteoporosis. A suspected mild cervical disc herniation or disc bulge is not necessarily a contraindication to manipulation, unless it is accompanied by signs of true radiculopathy such as progressive muscle weakness or sensory changes like numbness. Special care should be taken with patients who complain of headache or neck pain accompanied by confusion, visual disturbances, nausea, or alteration in consciousness. In such cases, vertebrobasilar insufficiency should be ruled out before attempting high velocity manipulation to the neck. These contraindications are well described in the chiropractic literature and covered in the curriculum of every chiropractic college.
Even in cases in which a contraindication to high velocity manipulation is present, a referral to a chiropractor may not be inappropriate. Almost all chiropractors are also trained in non-manipulative conservative methods such as soft tissue massage, physiological therapeutics, or low-force manual techniques.
A meta-analysis performed in 1996 by Hurwitz and associates at RAND found 67 studies that dealt with the outcomes of manipulation of the cervical spine. Fourteen were randomized trials, which were reviewed for quality and results. These randomized studies on neck pain varied widely in quality, but were essentially similar to those already discussed on low back pain. As with those studies, none indicated that the comparison treatment was more effective than manipulation; however, not all the studies found a statistically significant difference in favor of manipulation. They included nine trials of conservative treatment for acute, subacute, and chronic neck pain, including spinal manipulation. While most of these studies showed results that tended to favor manipulation, not all of them were statistically significant.
Analyzing the same nine studies on neck pain that had been studied at RAND, another team of investigators concluded in the British Medical Journal in 1996 that there was more evidence to support manipulation than any other common treatments for neck pain.
A landmark government sponsored study by chiropractor Dr. David Cassidy on "whiplash-associated disorders" appeared in Spine in 1995. After reviewing the literature on neck pain and its treatment, a blue-ribbon panel concluded that there was a dearth of high-quality research on the topic, but did single out spinal manipulation and mobilization as having at least weak cumulative evidence to support their efficacy. Their consensus recommendation from the Quebec Taskforce was that a short regimen of spinal manipulation and mobilization could be used for whiplash associated disorders.
In summary, randomized clinical trials, along with meta-analysis of the collective research, support the efficacy of spinal manipulation for acute and chronic neck pain, even though the findings are not always statistically significant.
In the 1996 RAND study on cervical spinal manipulation, Hurwitz and associates reviewed five randomized trials that assessed the effectiveness of spinal manipulation for headache. One trial focused on migraine, and the rest on muscle tension headache. Actually the highest-quality study on muscle tension headache by Boline in 1995 compared chiropractic manipulation with low-dose amitriptyline over six Modules. Four Modules after the end of treatment patients who had received manipulation maintained their improvement, while the patients on amitriptyline did not. Statistically significant differences were found in headache intensity and frequency, medication use, and functional status. Significant differences in favor of manipulation were found in the three other tension headache studies as well.
In the one randomized trial on migraine headaches by Parker in 1978, patients who received chiropractic manipulation were found to have significantly less pain intensity than those who received manipulation and mobilization by a physical therapist or M.D. There were no statistically significant differences in frequency or duration of headaches.
In a 1995 study by Nilsson, cervical spine manipulation was compared with low-level laser and deep friction massage for treating headaches. Patients receiving manipulation showed greater improvement in all variables, but not at statistically significant levels. In summary, the clinical trial data supporting the efficacy of spinal manipulation for headache appears promising, but is insufficient to draw strong conclusions
Throughout chiropractic's century-long history, chiropractors and their patients have reported clinical benefits from manipulation for a variety of conditions other than spinal pain syndromes. While there is a wealth of clinical anecdotes, there is great debate about whether or not spinal manipulation can produce significant effects beyond pain relief and increased function in the activities of daily life.
A small body of published clinical evidence now exists to suggest that spinal manipulation might affect some non-musculoskeletal health problems. A wide range of conditions have been reported to respond to manipulative procedures, including fibromyalgia, high blood pressure, asthma, menstrual pain, infantile colic, otitis media, childhood enuresis, dizziness and vertigo, chronic pelvic pain, and others. Published randomized trials on infantile colic by Wilberg and colleagues in 1999, and on premenstrual syndrome by Walsh and Polus in 1999, has shown reduction in these symptoms after chiropractic treatment. On the other hand, a study by Balon in 1998 failed to find a significant improvement in children with asthma when compared with simulated chiropractic treatment.
A 1999 study by Walsh in the Journal of Manipulative and Physiological Therapeutics suggested that PMS symptoms can be reduced by chiropractic treatment. In the prospective, randomized, placebo-controlled, crossover clinical trial, 16 women received spinal manipulation plus soft tissue therapy two to three times in the Module before menstruation for at least three cycles. Nine subjects received a placebo treatment with a spring-loaded adjusting instrument. Patients switched treatment groups after a one-cycle washout period. PMS symptoms appeared to lessen during chiropractic treatment when compared with placebo treatment, but no further improvement in symptoms occurred in the group receiving placebo treatment before chiropractic.
Fibromyalgia was the focus of a 1997 pilot study of 21 rheumatology patients aged 25 to 70. This Canadian study was published in the Journal of Manipulative and Physiological Therapeutics. They used a randomized control with a crossover design and showed that chiropractic treatment improved patient's cervical and lumbar ranges of motion, straight leg rise, and reported pain levels.
In a study comparing chiropractic treatment with medical treatment of otitis media (middle ear infection) in children, preliminary findings suggest that chiropractic adjustment had a significantly beneficial effect. How chiropractic manipulation might help otitis media is open to speculation. Perhaps it improves the nerve supply to the inner ear, or enhances immune function. Further study is needed to explore these possibilities.
One controlled study by Brennan in 1991 that may be relevant to this
question was conducted by researchers at the National College of Chiropractic
in Lombard, Illinois and published in the Journal of Manipulative and
Physiological Therapeutics. Ninety-nine chiropractic students were assigned
randomly to groups that received either sham spinal manipulation, thoracic
spinal manipulation, or soft tissue manipulation. Researchers found significant
increases in blood levels of substance P, an immune-stimulating chemical,
and monocyte responsiveness which is an immune cell measure in those who
received the true adjustment. Such research suggests that there may be
a pathway of influence between spinal manipulation and immune functioning.
It is also possible that spinal adjustments may help to relieve a state
of chronic stress that would tend to depress immune functioning.
In October 1998, the special CAM issue of the Journal of the American Medical Association reported that spinal manipulation by a chiropractor failed to alleviate tension headache in a Danish study. Finally, in 1998 a second New England Journal of Medicine reported study included chiropractors from the Canadian Memorial Chiropractic College. In this study 80 children with asthma were randomized into chiropractic treatment versus a stimulated or placebo treatment. The researchers concluded that in children with mild or moderate asthma, the addition of chiropractic spinal manipulation to usual medical care provided no benefit.
Writing an editorial in the New England Journal of Medicine that contained these studies, noted researcher, Dr. Paul G. Shekelle at the West Los Angeles Veterans Affairs Medical Center concluded, that nearly 20 years after a similar editorial by Dr. Arnold Relman, that there appears to be little evidence to support the value of spinal manipulation for non musculoskeletal conditions.
Other research on non-musculoskeletal disorders has been equivocal. A 1992 comparison by Kokjohn of manipulation and sham manipulation in the treatment of dysmenorrhea (menstrual pain) found no difference between the two treatment groups, with a similar reduction in endometrial prostaglandins, which are associated with cramp-like pain in both groups.
Two studies of hypertension yielded conflicting findings. In one study manipulation was found to have no effect on high blood pressure. While in the other study there was a reduction in blood pressure in the group receiving active treatment, as opposed to placebo and no-treatment groups.
A randomized study of patients with chronic asthma in 1995 found no significant difference between the group receiving manipulation and that receiving sham manipulation, although both groups reported a 36 percent improvement in their asthma symptoms.
Given the controversies regarding the adverse effects of long-term use of ß2-agonists and inhaled corticosteroids, a nonpharmaceutical approach that reduces the need for medication would be valuable. A substantial number of patients with breathing difficulties-including asthma-already receive chiropractic care, according to several surveys. Two studies of chiropractice treatment of asthma - one in adults, the other in children - both randomized, blinded, placebo-controlled studies with objective and subjective outcome measures found no objective improvement. Perceived benefit was equivalent between treatment and sham groups and thus could not be attributed to the spinal manipulation. The children reported primarily diminished asthma symptoms and ß-agonist use. The 36% improvement in adult bronchial hyperreactivity and 34% improvement in patient-reported asthma severity come strikingly close to the 30% placebo effect noted in most drug trials.
There are design limitations, however. What is important to note, is
that only mild to moderately severe asthma was examined. The absence of
oral steroid-dependent asthmatics prevents any statement regarding chiropractic
manipulation in severe asthma. Neither treatment was long term or frequent,
raising the possibility that a different schedule might reveal positive
effects not appreciated here. On the other hand, a major positive feature
of both studies was inclusion of a sham treatment group to control for
time spent with the physician and the experience of a hands-on procedure.
These studies can serve as a model for assessing body work modalities
and acupuncture with meaningful data interpretation.
A systematic review by Brontfort in 1996, of the clinical evidence supporting
spinal manipulation for non-musculoskeletal conditions was presented at
the 1996 International Conference on Spinal Manipulation in Bournemouth,
England. It concluded that manipulation seemed not to be efficacious in
the treatment of hypertension and chronic asthma of moderate severity,
but that the evidence was not strong enough to rule out conclusively the
use of manipulation for these conditions. Because of the small number
and poor quality of the studies, the reviewers concluded that there was
not enough evidence to recommend for or against the use of manipulation
in the treatment of vertigo, nocturnal childhood enuresis, dysmenorrhea,
chronic obstructive pulmonary disease, duodenal ulcer and infantile colic.
Further research is certainly needed in these areas.
There are very few systematic prospective studies of complications arising from spinal manipulation. Information about the potential harm from spinal manipulation is largely derived from case reports, series of cases, and cohort studies. The 1996 RAND study on cervical manipulation extensively discussed the benefits and risks of manipulation of the cervical spine, and found 118 cases of complications arising from this procedure in the English-language literature. Most were cerebrovascular accidents (strokes); twenty-one patients died and 52 survived with serious impairment, usually neurological. In an attempt to calculate the risk of cervical spinal manipulation, the RAND authors assumed that the published cases represent only one-tenth of the actual incidence. On this basis the risk for a complication of any sort was estimated at one per one million manipulations. Using the same assumptions, the rates of serious complications and death from cervical spine manipulation were estimated at 6 per 10 million and 3 per 10 million manipulations respectively.
Complications from lumbar spine manipulations appear to be quite rare. In the 1992 RAND study on low back pain, Dr. Paul G. Shekelle and associates estimated the risk of serious complications from lumbar manipulation as less than one case per 100 million manipulations. A comprehensive review by Assendelft published in Family Practice in 1996 surveyed reports in addition to those published in English, yielding 295 cases of complications from all types of spinal manipulation. This review also noted that no complications had been reported in any of the randomized clinical trials of spinal manipulation to date.
A 1996 retrospective cohort study in Denmark by Klougart examined the incidence of stroke after manipulation of the cervical spine. Treatments covered the period 1978-88, representing the experience of 99 percent of the practicing chiropractors in the country. Five cases of stroke were identified, one resulting in a fatality, yielding an average risk of approximately one case for every one million cervical manipulations.
Studies that have looked at the degree of satisfaction in patients seeking manipulative therapy or chiropractic care have demonstrated much higher patient satisfaction scores compared to other forms of treatment and other professions. There appears to be an overwhelming preference of patients with back pain for manual treatment. The difference is not as great when manipulation is compared to massage. This may be due to the time spent by chiropractors with a patient, the simply laying on of hands, the personal attention offered patients by most chiropractors or the frequency of visits which tend to be higher than for other treatments. A study by Dr. Pope demonstrated increased satisfaction the longer the care continued which suggests the latter may be part of the answer.
Patients who go to chiropractors tend to be more satisfied with their care than those who receive medical care for the same conditions. Patient satisfaction is a measurable concept that includes not only effectiveness of the treatment, but also the manner and setting in which it is given. Although satisfaction is not an outcome that is generally looked for in clinical trials, it is an important indicator of how the public perceives its health care professionals.
A study by Cherkin of the Group Health Cooperative of Puget Sound, in
1989 found the satisfaction levels of patients receiving chiropractic
care for low back pain were three times higher than in patients receiving
allopathic care. Other studies reported by Collinge in 1996 have found
that patients being treated by a variety of practitioners including chiropractors
for low back pain were least satisfied with conventional practitioners.
The importance of cost as an outcome measure is increasingly important in all areas of health care. There are 20 studies looking at the relative costs of chiropractic treatment in patients receiving workers' compensation. Fourteen of the studies demonstrated a lower cost compared to traditional care. Johnson and colleagues demonstrate the mean durability compensation pain to workers with back and neck injury was $264 compared to $618 for those treated by physicians. Jarvis et al compared treatment costs for identical diagnoses and noted treatment cost to be $527 for chiropractors and $684 for physicians. The number of treatments, however, was higher for the chiropractic patients who were also seen for longer periods of time.
The differences are less evident in the private insurance arena, and depend on the treatments to which chiropractic is being compared. A study by Carey in 1995, suggested that the costs for chiropractic care were similar to the costs of orthopedic care and less than the care by an HMO family practice physician. Patients showed much greater satisfaction with the chiropractic treatment than the comparative treatments.
Most studies on the economic variables in chiropractic care compared with other forms of care do not focus on spinal manipulation as such, but rather on general differences between chiropractic and medical providers. In randomized clinical trials in Great Britain by Meade in 1990 and 1995, chiropractic care was compared with hospital outpatient management, including traction and physical therapy. Researchers concluded that the routine use of chiropractic care in the British health system would save considerable money. Patients randomly assigned to chiropractic care had better reduction in pain and recovery from disability, even at two- and three-year follow-ups.
A number of retrospective actuarial studies have attempted to compare the cost of medical care and chiropractic care, usually for low back pain. A study by Canadian health economist Pran Manga, funded by the Ontario Ministry of Health in 1993, reviewed the clinical and economic literature with respect to chiropractic. It concluded that the evidence is overwhelmingly in favor of much greater use of chiropractic care in the management of low back pain, in terms of safety, efficacy, and cost-effectiveness, as compared with medical management of low back pain. However, other experts have looked at the same body of literature that Manga reviewed and questioned whether his conclusions were justified by the available data.
A 1996 study by Mosely in a managed-care setting concluded that chiropractic care reduced the use of expensive technology, maintained a high level of patient satisfaction, and did so at a lower cost. Health economist Miron Stano compared 6,183 patients with cases of comparable severity who received either chiropractic care or medical care in a large insurance-related database in 1995. Chiropractic episodes were less costly, largely because of lower hospital costs. Although, the chiropractic cases involved a longer period of care, this was not associated with higher costs. Chiropractors also retained a higher proportion of patients returning with recurrent episodes than conventional physicians.
Several studies have shown that patients receiving spinal manipulation have an overall reduction in work time loss compared to other forms of treatment. With one exception the literature reports reduction in disability days and shortened periods of symptoms in 17 studies comparing chiropractic or manipulation to other treatment methods. In 1991, Nyiendo and Lamm report that there was also a higher frequency of early return to work following chiropractic care. Also, in a 1991 review of workers compensation claims in Utah, Jarvis and associates compared the cost of medical and chiropractic claims for patients with the same diagnosis, and found that patients who received medical treatment cost ten times more in compensation costs than the average chiropractic patient for the treatment of low back pain, even though the chiropractic patients tended to pay a little more per individual treatment.
Not all published research confirms that chiropractic treatment is more cost-effective than allopathic care. Carey and associates in the New England Journal of Medicine in 1995 compared North Carolina patients with low back pain who went to urban and rural chiropractors and orthopedists, and those who presented to primary-care physicians in a managed-care setting. There was no statistically significant difference in clinical outcomes between providers, but chiropractic treatment was found to be the most expensive care followed by orthopedists. Patients, however, reported being more satisfied with chiropractic care.
In summary, the evidence is equivocal as to whether chiropractic care
is more cost-effective than medical care, and it is a hotly debated issue.
While some studies have tended to favor the cost-efficiency of chiropractic,
others suggest that it is as expensive as other forms of treatment. At
a time when the health care reimbursement system is rapidly changing,
a challenging opportunity exists for researchers and economists to conduct
additional studies on the relative cost-effectiveness of chiropractic
Chiropractic is arguably the most successful and integrated of the "alternative" professions in the United States. By some criteria it could be considered a "mainstream" health profession.
There are approximately 50,000 licensed Doctors of Chiropractic (DC) in the United States, making chiropractors the fourth largest group of health care professionals, behind physicians, nurses, and dentists. Within chiropractic there is an ongoing professional identity debate between being musculoskeletal specialists versus primary care providers. Approximately 15 to 20 million Americans visit chiropractors each year, at an estimated cost of at least $5 billion. The number of people using chiropractic in this country has doubled since 1980.
Almost all chiropractic training takes place in privately supported, freestanding institutions designed expressly for that purpose. Very few chiropractors can be found in non-chiropractic academic settings, although this is gradually changing. There are 16 chiropractic colleges in the United States, all accredited by the federally recognized Council on Chiropractic Education (CCE) which is an accrediting organization recognized by the U.S. Department of Education. Admission to a chiropractic college requires at least two years of undergraduate study, but does not necessarily require a bachelor's degree although six states require it for licensure. Between one-third and one-half of chiropractic students have received undergraduate degrees or higher before beginning chiropractic training reported.
Chiropractic colleges have a 4-5 year professional curriculum similar in content and structure to medical education. Many of the basic science textbooks are the same as those used in allopathic medical schools. In fact chiropractic students have more classroom hours in anatomy and radiology than most allopathic doctors. In addition, chiropractic students are trained in chiropractic techniques and philosophy.
Although chiropractors generally describe themselves as holistic, natural healers, critics argue that they do not have adequate training to function as family doctors. Perhaps the most notable deficiency in chiropractic education is in clinical training. According to a comparison of schools published in the Journal of Chiropractic Education in 1990, medical students average 2825 clinic hours, while chiropractic students have only about 800 hours, mostly dealing with musculoskeletal problems. Moreover, after medical school most physicians spend several years in supervised clinical training, whereas newly graduated chiropractors tend to enter into practice immediately upon graduation.
In spite of such criticisms, chiropractic has gained increasing acceptance among a modest percentage of the conventional medical community. More and more chiropractors have hospital staff privileges, are recruited by health maintenance organizations, work at multispecialty back centers, are appointed to workers compensation medical examination boards, and are commissioned as health care providers in the armed forces.
Integration of chiropractic into most medical and healthcare delivery systems has led to the necessity of communication between medical and chiropractic physicians. More and more chiropractors are willing to write consultation reports and follow-up notes to keep primary care or family physicians informed of a patient's progress and treatment recommendations. This is more likely to occur, however, if their physician requests such a report and is willing to communicate back to the chiropractor any recommendations, concerns or other treatments the doctor may be considering.
One of the concerns of patients is that they will be criticized by their medical physician for going to a chiropractor and by their chiropractor for simultaneously taking medication. This can be more serious than any philosophical disagreements that the professions may have with each other. Many of the negative and potentially harmful effects and concerns about chiropractic can be eliminated if there is communication between all health professionals treating a patient, and the realization that such communication exists by the patient.
Chiropractic medicine is licensed in all fifty states and in the District of Columbia. To be licensed as a chiropractor one must have graduated from an accredited chiropractic college, and also must pass three to four examinations given by the National Board of Chiropractic Examiners. In addition, in several states chiropractors must pass a state board exam. All but six states also require that they get a certain number of continuing education hours each year.
The majority of chiropractors are generalists and do not practice a specialty, but there is extensive postgraduate training available for chiropractors. Such programs may take up to three years, leading to board certifications in areas such as radiology, sports injuries, orthopedics, nutrition, internal medicine, and neurology.
Spinal manipulative therapy should serve as an example to proponents of other treatment methods. Proper outcome studies are the primary tool for clinicians to legitimize their favorite methods of managing patients with back pain. The outcomes, which have to be satisfied, are pain relief, objective physical changes, cost effectiveness, reduced disability, and patient satisfaction. Chiropractors have not proved conclusively that they can satisfy all these requirements for every condition they claim to treat. They, however, have gone further than proponents of most other alternative or complementary treatment methods in the time and research they have dedicated towards this goal.
A recent survey of CAM coverage of employers by Price, Waterhouse, Coopers found that chiropractic was the most widely covered complementary therapy and is a typical rather than exceptional benefit. Various surveys show that up to 85 percent of employers, depending on the size of their firm, offer some chiropractic coverage.
The current ambivalent status of chiropractic may presage challenges in the nascent integration of other therapies and providers. The position of chiropractic is described below.
Chiropractic is nominally included, but there is little MD referral. That "control" is the correct verb to use with regards to the medical establishment and chiropractic is apparent when the following finding is considered. When health plan members are required to get a note from their medical doctors prior to seeing chiropractors, utilization shrinks by 75 percent. Comparison of chiropractic utilization in managed Medicare vs. direct-access, fee for service Medicare shows an even steeper drop- 90 percent, according to 1999 data, from the formerly named Health Care Financing Administration (HCFA), now known as the Centers for Medicare & Medicaid Services (CMS)."
Accepted use is only a fraction of the licensed scope. Even if chiropractors were full-fledged players in integrated teams for care of low back pain, the profession would remain in a quandary. Most chiropractors and their patients would argue that allowing chiropractic only for treatment of lower back pain understates the value of chiropractic and shrinks the licensed scope of practice.
A recent review by Dr. McCroy and researchers from Duke University that looked at treatments for headache suggests that the therapeutic benefits of chiropractic may extend beyond the alleviation of low back pain. A Dutch study conducted by Leboeuf and colleagues suggests that the potential of chiropractic, if appropriately utilized, may not be limited to the spine. In their study, an average of 21 to 25 percent of chiropractic patients reported nonstructural benefits ranging from improved vision, easier breathing, and better digestion.
Whether or not chiropractic has even made limbo status is questionable, considering two recent developments. First, when the Joint Commission on Accrediation of Healthcare Organizations issued clarifying comments on pain guidelines neither chiropractic nor manipulation were among the half-dozen CAM therapies listed as "nonpharmacological" approaches which may assist people in reducing pain. Chiropractic's peculiar relationship with mainstream delivery is also evident in a survey of 28 hospital-sponsored "integrative clinics." This survey found that just five clinics had chiropractors in their service mix. Many have informally suggested that the exclusion is due to opposition from orthopedic specialists in the sponsoring system.
No single chiropractic organization has a majority of members, and many practitioners do not belong to any organization. Among the current organizations are: the International Chiropractors Association (ICA) founded by Bartlett Joshua Palmer, the son of the founder of chiropractic, Daniel David Palmer. It is the oldest of the chiropractic organizations with 5 to 10% of United States chiropractors as members. Membership includes both straight and mixer chiropractors, but straight chiropractors predominate. The ICA promotes the subluxation approach to chiropractic and has a more traditional orientation. It publishes the ICA Review, and can supply a list of licensed members who practice in a given area.
The American Chiropractic Association (ACA) has the largest membership and includes as many as 25% of United States chiropractors. Each state has a chapter. Today the ACA publishes the Journal of the American Chiropractic Association. Mixers constitute the majority of this organization, but the exact proportion of mixers to straights is unclear.
Finally, the World Chiropractic Alliance is an international association of chiropractors with a single emphasis on the vertebral subluxation approach. It publishes two periodicals, True Health and The
Chiropractic Journal. Both the WCA and the National Association of Chiropractic Medicine are proprietary organizations and have small memberships in the hundreds.
The formerly named Association for Network Chiropractic
is now known as the Association for Network Care, and its focus is on
the release of subluxations. Membership requires training in Network Chiropractic,
consisting of four Moduleend seminars. It publishes a directory of Network
Chiropractic practitioners, over 500 nationwide.
Since the settlement of the chiropractors' antitrust suit against the
AMA in 1987, relations between chiropractic and allopathy have steadily
improved. Almost all chiropractors today have reciprocal referral relationships
with physicians, and chiropractors are often included in interdisciplinary
Chiropractic can be integrated with other medical traditions, as evidenced by the growing number of chiropractors who include nutritional counseling, homeopathy, and other natural therapies in their practice. Some chiropractors do not employ manipulation at all, using their broad mandate as licensed health professionals to concentrate on other complementary health modalities.
A review of chiropractic published in Consumer Reports in 1994 maintained the same skeptical stance that it took in 1975, when it conducted a major investigation of the profession. In their first report, the magazine reported that chiropractors were likely to use unnecessary x-rays, perform manipulations on infants and children, and propose unnecessarily lengthy courses of treatment, as well as advocate chiropractic manipulation for serious problems that needed medical attention. A great deal of reform has taken place in the profession since that time, with improvements in education, research, and collaboration with other health care providers. Nevertheless, Consumer Reports in 1994 continues to argue that the chiropractic profession may still be hampered by its adherence to an outmoded belief system and unscientific practices.
Much of D.D. Palmer's notions of health and disease do not hold up in
the light of modern scientific knowledge. Research oriented chiropractors
believe that it is time to evolve beyond the old chiropractic philosophy
and maintain a professional focus on the scientific treatment of musculoskeletal
Beyond the research efforts described in the preceding section, which focused on randomized trials, the chiropractic profession has taken significant steps to develop a research infrastructure, including the creation of the aforementioned Consortium for Chiropractic Research, defining and prioritizing research topics, linking with non-chiropractic research centers, designing and executing pilot studies, establishing peer-reviewed and indexed journals, and cultivating sources of funding. Among other future directions would be to compare different types of spinal manipulation with conventional physical treatments that are already in common use, such as McKenzie physical therapy and massage.
In 1994 the Bureau of Health Professions of the U.S. Health Resources and Services Administration (HRSA) initiated a Chiropractic Demonstration Grants Program, which for the first time gave chiropractic institutions an opportunity to compete for funds, to do studies on back and spinal related pain, in collaboration with medical institutions. Three chiropractic schools were awarded grants. In addition, the Palmer College of Chiropractic received a series of contracts to evaluate the role of chiropractors in interdisciplinary training on rural health and geriatrics.
Another HRSA contract funded the first interdisciplinary Conference to Develop the Chiropractic Research Agenda in 1996. Participants in the resulting conference created position papers and annotated bibliographies summarizing the state of the art in chiropractic-related research, and made specific recommendations for further research.
As of 1998, the National Institutes of Health NCCAM initiated funding of chiropractic research efforts. This was based on the OAM releasing a request for applications to establish a Center for Chiropractic Research. Dr. William Meeker and Palmer College of Chiropractic received funding, and it was the first time that the NIH had formally recognized chiropractic as a significant research topic.
In 2002, Dr. Fayez Ghishan and Dr. Andrew Weil headed up the CAM Pediatric Research Center at the University of Arizona School of Medicine in Tucson. The goal of this Center is to study integrative approaches in pediatrics. Three Phase II trials investigate the role of alternative approaches to very common pediatric problems for which there are currently no good conventional medical therapies:
Chiropractic research has acquired further legitimacy by gaining recognition
from the American Public Health Association that voted in 1995, to establish
a full-fledged Chiropractic Health Section, which could present research
at its organization's meetings. Chiropractic research is also presented
regularly at professional meetings of the North American Spine Society
and American Back Society, as well as at international conferences. Recent
sessions of the International Conference on Spinal Manipulation and the
World Federation of Chiropractic included presentations on at least a
dozen ongoing randomized clinical trials of chiropractic procedures for
a variety of musculoskeletal and non-musculoskeletal conditions.
Most significantly with regard to the future of chiropractic research and clinical practice is the NIH funding of the Consortial Center for Chiropractic Research, under the direction of Dr. William C. Meeker, to create the gold standard for evidence based chiropractic. Also, in keeping with a robust future for chiropractic, in the mainstreaming of CAM practices into conventional health care is a report for the United States Agency for Health Care Policy and Research (formerly
AHCPR, now AHRQ). The report was established under the working title of Chiropractic in the United States: Training, Practice and Research, and was funded through an AHCPR grant by Dr. Daniel C. Cherkin of the Group Health Cooperative of Puget Sound and Dr. Robert D. Mootz of the Washington State Department of Labor and Industries. This report is the best analytic summary of the state of the science undergirding chiropractic medicine. It serves as a major landmark in establishing evidence based chiropractic care, and it serves as a beacon for its future research and clinical standards and practices.
There is sufficient evidence from clinical research to conclude that
spinal manipulation is effective for some forms of common low back and
neck pain, and is probably effective for at least some headache patients,
but additional research is required in the latter area. There is a dearth
of strong randomized clinical trial research on the effectiveness of spinal
manipulation for non-musculoskeletal disorders.
Chiropractic patients generally report greater satisfaction with their
care than, do patients who go to allopathic practitioners. While the components
of patient satisfaction are not readily quantified, it is a measure of
treatment outcome that deserves closer scrutiny.
What are the potential benefits and risks of chiropractice care for older Americans?
1. The legitimization of chiropractic and its integration into the health care system has been achieved through a professional emphasis on research, in an attempt to define the benefits and risks of spinal manipulation, using accepted outcome measures.
2. The central tenets of chiropractic are that all living things are endowed with a life force that regulates all vital functions termed "innate intelligence", and that the human organism can keep itself healthy if there are no barriers to the full expression of this. It is believed that the "innate intelligence" flows through the nervous system to all parts of the body. Due to the fact that the nervous system and musculoskeletal system are intimately intertwined and interrelated, any distortion of the spine could cause illness in any part of the body supplied by the nerves. By manipulating the spine and other joints through which the nervous system passes, the chiropractor can remove obstacles to the full expression of the "innate intelligence" and help restore the body to health.
3. Chiropractic's greatest strength is in the treatment of neuromusculoskeletal conditions, such as sprains or strains of the back and related structures.
4. Few published reports of serious complications arising from spinal manipulation exist. Whether conventional or chiropractic, these may be underreported, since complications are not often documented adequately in most clinical practices.
5. Almost all chiropractic training takes place in privately supported, freestanding institutions designed exclusively for training in chiropractic medicine. Chiropractic colleges have four to five year professional curriculums, similar in content and structure to the allopathic medical education. Typically, chiropractic students have more classroom hours in anatomy and radiology than most allopathic medical students.
6. The most notable deficiency in chiropractic education is in clinical
training. Allopathic medical students typically average 2,825 clinical
hours, while chiropractic medical students average 800 clinical hours.