Producer's Response

The Scientific American Frontiers episode, "A Different Way to Heal" set out to examine some widely used approaches to health care in the rapidly expanding field of alternative medicine. The aim throughout the program was to ask what science has to say about these alternative approaches and their respective underlying theories.

The segment entitled "Adjusting the Joints" explored the subject of chiropractic as a healing art and science. The segment delved into the origin and theory of chiropractic, presented a number of specific techniques via trained chiropractors and their patients, and raised questions about some aspects of chiropractic, including evidence for the underlying principle of "subluxations" and the connection between spine alignment and health, methods of diagnosis, and the safety of certain forms of neck adjustment.

The segment did not claim that chiropractic is fraudulent and did not attempt to prove or disprove that chiropractic "works," but it does state that chiropractic has no basis in science. This conclusion is entirely justified by both current research and generally accepted views of human anatomy.

The underlying principle of chiropractic theory is that there is a direct association between the shape of the spine (the alignment of the vertebrae and the spine's curvature) and disease. Chiropractors claim that health problems can be caused by "subluxations," or blockages of nerve energy, which are caused by malpositioned vertebrae. By "adjusting" vertebra— manually exerting force on the spine so as to physically displace parts of the skeleton—chiropractors say they are removing the subluxation and hence allowing the body to heal itself. We felt it was important to review the scientific evidence for the existence of subluxations, as defined by chiropractors. We reviewed the scientific literature, with the guidance of a number of qualified medical sources, and concluded that there was no such evidence available in any form which would meet generally accepted scientific standards. On the contrary, there is scientific literature failing to find subluxations and associated phenomena stretching back thirty years, as was noted in the program.

Some viewers commented that the story was biased against chiropractic. We made a serious effort to give the chiropractic profession the opportunity to present their own case. Those in the segment supporting chiropractic included: the president of one of the most established and best-known chiropractic colleges in the country; three experienced and fully licensed Doctors of Chiropractic demonstrating and explaining in detail three different widely used techniques; and a patient who expressed her satisfaction with chiropractic treatment. To counter those five pro-chiropractic individuals we presented two individuals critical of chiropractic: a medical doctor and a former Doctor of Chiropractic who practiced for many years and who taught at a major chiropractic college. We allowed each of the individuals included, both pro and con, to express their own opinions. Other factual information conveyed in the segment included direct quotations from Daniel Palmer, the founder of chiropractic, and references to specific published papers in the medical literature.

Other viewers commented that the program ignored positive studies on chiropractic and included only negative studies. While it's true that there are many studies which purport to show the benefits of chiropractic, there are in fact very few which were conducted to the highest scientific standards. In reviewing research on chiropractic we held papers to those standards and looked for rigorous, well-designed studies that appeared in solid, peer-review medical journals. Our advisor in analyzing studies on chiropractic was Dr. Wally Sampson, a retired Stanford Medical School professor and editor of The Scientific Review of Alternative Medicine. In that high-quality category there are in fact very few positive papers supporting benefits of chiropractic for particular health problems. The one area where there is significant published evidence of chiropractic benefit is in treating back pain. Valid studies have shown that chiropractic can be of benefit to back pain sufferers. However, chiropractic success rates were no greater than conventional approaches like physical therapy and exercise. Since many chiropractors use procedures that are similar to those of conventional therapies, which do not require any belief in theories of subluxation and spinal displacement, the back pain studies cannot be used to validate chiropractic theory. Because we felt the subject of chiropractic and back pain was likely to be of importance for many viewers, we created an expanded discussion of the subject on the the Scientific American Frontiers Web site with the feature entitled "Keeping the Spine in Line."

On the question of chiropractic neck adjustments and stroke, some viewers questioned the statistics we used and expressed concern that stroke risk was exaggerated. Referring to a recent Canadian study, what we said was, "20% of all strokes caused by artery damage could be a result of neck manipulation. That translates into more than 1300 strokes a year in the US." We used the phrase "artery damage" to substitute for the technical term "vertibrobasilar dissection." That being said, our narration was a precise and accurate representation of the study in question. Other viewers wished that we had cited more studies on the stroke question. Indeed, we could have if not for time constraints. One British study we would have liked to discuss looked carefully at the question of under-reporting surrounding stroke and neck manipulation. In the study, neurologists who routinely treat stroke emergencies were first surveyed to see if they ever asked patients if they'd had a chiropractic neck manipulation recently. It was found that neurologists did not ask, as a rule. Then the neurologists were instructed to ask their patients as a matter of course. The incidence of chiropractic-related stroke shot up. So this wasn't just under-reporting that the study revealed — more like zero reporting. It seems that patients and neurologists have not been making connections between events which, of course, may well be days apart. The question of under-reporting — or more accurately of simply missing cause and effect — discussed in the Canadian study as well, is clearly now beginning to get more attention in academic circles.

In summary, we believe "Adjusting the Joints" was fair, accurate and balanced and, in conjunction with the other segments of "A Different Way to Heal" contributed to a more informed public understanding of a significant trend in health care today.

Chedd-Angier
June 11, 2002