Overview of Chiropractic

Chiropractic was invented by D. D. Palmer, Sep 18, 1895 when he adjusted the spine of a deaf man and allegedly restored his hearing (a claim that is highly implausible based on what we know of anatomy). Based on this one case, Palmer decided that all disease was due to subluxation: 95% to subluxations of the spine and 5% to subluxations of other bones.

The rationale for chiropractic hinges on three postulates:

Bones are out of place Bony displacements cause nerve interference Manipulating the spine replaces the bones, removing the nerve interference and allowing Innate (a vitalistic life force) to restore health. There is no credible evidence to support any of these claims.

Real subluxations (partial dislocations) show up on x-ray. Chiropractic “subluxations” don’t. In view of the negative x-ray evidence, chiropractic was forced to change its definition of a subluxation from “a bone out of place” to “a complex of functional and/or structural and/or pathological articular changes that compromise neural integrity and may influence organ system and general health.”

Chiropractors are divided into straights and mixers. The straights limit themselves to chiropractic adjustments; the mixers add a variety of other methods ranging from massage to outright quackery like applied kinesiology. Upper cervical chiropractors focus on the atlas, the top cervical vertebra.

In over a century, chiropractic research has produced no evidence to support the postulates of chiropractic theory and little evidence that chiropractic treatments provide objective benefits. Research on spinal manipulation is inherently difficult, because double blind studies are impossible and even single blind studies are problematic; a placebo response is hard to rule out.

There is good evidence that spinal manipulation therapy (SMT) is effective for some patients with low back pain but that it is not superior to other treatments. There is controversial evidence of lesser quality supporting the use of manipulation for neck pain and headaches. SMT is not exclusive to chiropractic: it is also used by physical therapists, doctors of osteopathy, and others. There is no acceptable evidence that chiropractic can improve the many other health problems it claims to benefit, from colic to asthma. There is no evidence to support the practice of adjusting the spines of newborns in the delivery room or providing repeated lifelong adjustments to maintain health or prevent disease.

Up to half of patients report short-term adverse effects from manipulation, such as increased local or radiating pain; and there is a rare but devastating complication of neck manipulation: it can injure the vertebrobasilar arteries and cause stroke, paralysis, and death. Some chiropractors do not accept the germ theory of disease and only about half of them support immunization. Many of them discourage proven treatments with drugs and surgery and many want to take on the role of primary health care provider.

In their book Trick or Treatment, Simon Singh and Edzard Ernst reviewed the evidence for chiropractic and concluded: “Chiropractors… might compete with physiotherapists in terms of treating some back problems, but all their other claims are beyond belief and can carry a range of significant risks.”

From Science-Based Medicine. With permission