Chiropractic was defined by Daniel Palmer, its founder, as “a science of healing without drugs.” However, the underpinnings of chiropractic are not rooted in science. In fact, Palmer himself noted that chiropractic ideas could not be researched or subjected to experiments, and he considered chiropractic to be akin to a religion.(7)
The theory behind chiropractic is that disease is caused by spinal subluxations.(7) In medicine, subluxation is the term for a partial joint dislocation. However, this word is used differently in chiropractic, where a subluxation is a more abstract construct that refers to functional or structural changes in the musculoskeletal system. These changes are thought to compromise the integrity of the nervous system, thereby affecting the patient’s organs and health.(8) Palmer furthermore wrote of what he called innate intelligence, which is related to the body’s ability to heal itself. This innate intelligence cannot function properly in the presence of subluxations. Thus, the goal of chiropractic is to detect and correct subluxations via spinal manipulation in order to allow innate intelligence to flow freely throughout the nervous system.(7,8)
Currently, there are two basic camps of chiropractors, the so-called “straights” and the “mixers.” Straights continue to accept the ideas of Palmer, including his theories of innate intelligence, subluxation as the cause of all disease, and spinal manipulation as the cure for all disease. Thus, the straights use only spinal manipulation to treat their patients, and they do not work with conventional physicians. In contrast, mixers view themselves as more of musculoskeletal pain specialists, especially for the treatment of back pain. They use other forms of treatment along with spinal manipulation, and they are more likely to work with the medical establishment. Early in the history of chiropractic, Palmer claimed that mixers were essentially defiling its tenets, but today, mixers comprise the majority of chiropractors.(7)
Spinal manipulation, also called adjustment, is performed by applying a force to a specific joint with the intention of moving vertebrae beyond the normal range of motion, but not far enough to cause damage. These manipulations are believed to break down adhesions in joints, affect mechanoreceptors in the joints, inhibit C-fiber-mediated perception of pain, and/or modulate function of the central nervous system.(7) A clicking sound often occurs during an adjustment as the stuck joint is released.(8)
Most patients who visit chiropractors are self-referred, and many of them come to chiropractors due to the inability of conventional medicine to adequately treat their pain. Chiropractors who are mixers mainly treat chronic pain caused by musculoskeletal problems, especially back and neck pain. Along with spinal manipulation, they may also use heat, cold, electrotherapy, herbal remedies, nutritional supplements, massage, meditation, and other non-pharmaceutical therapies. Mixers may also use conventional diagnostic tools such as radiographs and blood or urine analysis. Compared to straights, mixers are more willing to acknowledge that part or even most of the effect of chiropractic is due to the placebo effect. Unlike straights, mixers are also more willing to accept the idea that immunization is beneficial.(7)
The chiropractor with whom I worked was easily identifiable as a mixer. Along with spinal manipulation, he made use of heat and cold, massage, ultrasound, electrotherapy, and herbal remedies. For example, he recommended echinacea and high dose vitamin C to one patient with bronchitis. In addition, he openly acknowledged that certain conditions were better treated by allopathic or osteopathic physicians, and noted that pharmaceuticals were necessary in some circumstances. In keeping with his general open-mindedness toward conventional medicine, he presented himself as a chiropractic physician, and even stated that he considered chiropractic to be mainstream rather than alternative medicine. Finally, he described the science coursework he had taken in great detail to one of his patients and me, particularly emphasizing his training in physics and biomechanics. If he believed in Palmer’s ideas about subluxations or innate intelligence, he did not at any point indicate that.
The patients whom this chiropractor treated were mainly chronic pain patients. At the beginning of a session, he would test each patient’s range of motion and ask the patient to rate his or her pain level on a scale of 0-10. Next, he would palpate the patient’s vertebrae one by one, asking the patient if there was any pain at each level. Then he would begin adjusting the patient’s spine. Several patients were elderly and had arthritis, especially back and joint pain. These patients were treated with a mixture of lumbar spinal manipulation, heat, cold, ultrasound, and massage. There were also a few patients who had been rear-ended in car accidents and were suffering from whiplash. The treatment for whiplash was similar, except that the chiropractor focused more on manipulating the cervical spine rather than the lumbar spine. At the end of each session, the chiropractor would again ask the patients to rate their pain on a scale of 0-10. In every case, the patient’s pain had diminished, sometimes all the way down to the zero level. The patients generally agreed that the treatments were helpful.