Chiropractic: A Profession at the Crossroads of Mainstream and Alternative Medicine

Chiropractic is the largest, most regulated, and best recognized of the professions that have traditionally functioned outside of mainstream medical institutions and, in the new lexicon, have fallen into the category of complementary and alternative medicine. It is unique in the United States as the most widely disseminated indigenous U.S. system of healing. Its steadily increasing acceptance and use by the public and payers indicate that chiropractic is no longer the marginal or deviant profession it was once considered to be (1). According to surveys of patients seeking alternative care, chiropractors are used more often than any other alternative provider group (2), and the satisfaction with chiropractic care is very high (3, 4). The number of chiropractors is growing: The current number of 60 000 is expected to reach 100 000 by 2010 (5). Although some observers suggest that the profession may be entering the health care mainstream (6, 7), chiropractic remains a young profession; in 1995, it celebrated its 100th anniversary. Until the mid-1970s, chiropractic was considered to be outside mainstream medicine, often an outcast, and most chiropractors viewed themselves as differing in philosophy and practice from other health care practitioners (8). During the past two decades, there has been a marked change in the manner in which chiropractic is viewed, not only by mainstream medical practitioners (9) and institutions (10, 11) but also by members of the profession itself (12). Examining the factors that led to this change in attitude and the legitimization of chiropractic as a method of treatment and as a profession, as well as the conflicting emotional discussion that has accompanied these changes, is an interesting and informative exercise in health care sociology (13). The changes in the chiropractic (and medical) profession are, however, still in the transitional phase, and the acceptance and even the future role of chiropractic in the overall health care system remain controversial (14, 15). The Origins and History of Chiropractic Chiropractors have designated 18 September 1895, when Daniel David Palmer reportedly gave his first spinal adjustment, as the origin of the chiropractic profession; however, spinal manipulation is one of the oldest and most widely practiced healing methods. References to spinal manipulation, and even the term subluxation, can be traced back as far as Hippocrates and Galen (16), and manual and manipulative procedures have been depicted in the art and writings of most ancient cultures. Although manipulation has been part of orthopedic medical practice for centuries, most nonmedical practitioners of spinal manipulation in the 19th century were bonesetters who had learned their skills primarily by apprenticeship and observation (17). The early and middle years of chiropractic were dominated by charismatic and authoritarian figures who often disagreed with one another. Many of the early schisms around the theory and scope of practice from this period still exist in some form (9, 17). Daniel David Palmer, who originally practiced as a lay magnetic healer, is credited with professionalizing the practice of spinal manipulation. He integrated popular natural health and scientific models of the day to present a unique theory of chiropractic. He did this by incorporating the concept of an inherent healing ability of the body, which he named innate intelligence, into concepts drawn from contemporary knowledge about anatomy and physiology. He eschewed the use of drugs and surgery as unnatural invasions to the body and focused on what he perceived as normalizing the function of the nervous system as the key to health (17). From the beginning, chiropractors understood that professional self-regulation and independent legal status were crucial to survival. This stormy history of the first century of chiropractic includes many milestones on the march to professionalization, some of which are listed in Table 1. Although chiropractic originated in the United States (the primary training ground and theoretical inspirational source for chiropractors), it took less than 10 years for chiropractors to immigrate and begin practice in other countries. In 1923, the province of Alberta in Canada became the first jurisdiction to license chiropractic outside of the United States; in 1939, the canton of Zrich in Switzerland was the first to license the profession outside of North America. Today, chiropractors are licensed and regulated in many countries throughout the world (18) and are permitted to practice in most countries, pursuant to general law. Table 1. Events in the Historical Development of Chiropractic Chiropractic in Health Care One indicator of chiropractic mainstreaming is the steadily increasing use by patients in the United States, which has tripled in the past two decades from about 3.6% according to a 1980 survey (19) to an estimated 11% according to a 1997 national random telephone survey (2). This translates to an estimated 190 million patient visits to chiropractors in a year, or about 30% of visits to all complementary and alternative practitioners (2). One recent survey of family physicians and chiropractors in North Carolina (20) found that two thirds of the medical physicians felt moderately or very informed about chiropractic. Furthermore, 65% admitted referring patients to chiropractors, and 98% of chiropractors made routine referrals to physicians. Payments for chiropractic care historically came directly from patients' pockets until chiropractic services were included in Medicare in the 1970s. In the past few decades, chiropractic has been included in a substantial proportion of private and public insurance plans, all state workers-compensation systems, and all forms of managed care (including health maintenance organizations). More than 50% of health maintenance organizations and more than 75% of private health insurance plans now offer chiropractic services (21). Under order of the U.S. Congress, the military health care system has initiated a series of demonstration projects to investigate the feasibility of providing chiropractic care to military personnel. Chiropractic Training and Licensure From many proprietary schools hastily established during the first part of the 20th century, a stable number of chiropractic training institutions have emerged in the United States. Unlike in the United States, where all but one college are privately funded, chiropractic education in Australia, South Africa, Denmark, one college in Canada, and two in Great Britain is provided at established government-sponsored universities and colleges. Most colleges in the United States are accredited by the Council on Chiropractic Education, an agency certified by the U.S. Department of Education. Each college requires at least 4 academic years of professional education before students can qualify for licensure examinations. A minimum of 60 units of prescribed college-level courses (increasing to 90 units by 2002), mostly in the sciences, is required before admission to chiropractic college. Approximately 50% of students enter chiropractic training with a baccalaureate degree. A recent study described U.S. chiropractic curricula as an average of 4820 classroom and clinical hours, with about 30% spent in the basic sciences and 70% in clinical sciences and internship (22). Medical school curricula average about 4670 hours with a similar breakdown. Compared with medical students, chiropractic students spend more hours in anatomy and physiology but fewer in public health. Both programs have similar hours in biochemistry, microbiology, and pathology. Chiropractic curricula provide relatively little instruction in pharmacology, critical care, and surgery but emphasize biomechanics, musculoskeletal function, and manual treatment methods. Medical education has more than twice as many hours in actual clinical experience but 1000 fewer hours in didactic and workshop-like clinical courses. All chiropractic colleges maintain busy training clinics that deliver chiropractic care in settings similar to typical chiropractic practice. Specialty training is available in 2- to 3-year postgraduate residency programs in radiology, orthopedics, neurology, sports, rehabilitation, and pediatrics. Coursework leads to eligibility for accredited specialty board competency examinations, which confer diplomate or certified status. Forty-six states either recognize or require passage of examinations administered by the National Board of Chiropractic Examiners in the areas of basic science, clinical science, and clinical competency before granting a graduate a license to practice. Most states also require annual proof of continuing education credits for ongoing license renewal. Chiropractic Health Care and Practice Characteristics Chiropractic is an evolving health profession with functions, values, traditions, and training institutions similar to those of other professions. As envisioned by its founder, chiropractic was to be a revolutionary system of healing based on the premise that neurologic dysfunction caused by impinged nerves at the spinal level was the cause of most dis-ease and that spinal manipulation (adjustment) removed the interference to a full and healthy expression of life. Modern chiropractic theory and practice have moved away from the original monocausal theory, and research is gradually redefining the nature of the discipline and its education. Many still think chiropractic is synonymous with spinal manipulation, but as described below, this is only partially accurate. With the advent of the category complementary and alternative medicine (CAM), chiropractors themselves are divided about how to define the profession; many do not want to be termed CAM practitioners (23). Chiropractors have many of the attributes of primary care providers and often describe themselves as such (24). Others point out that chiropract