The various ideas and interventions that are gathered under the broad umbrella of "alternative" medicine range the spectrum from plausible but untested to demonstrable nonsense (paraphrased from Barry Beyerstein). The only thing they have in common is that they are not adequately supported by scientific evidence.
I have a fascination with the demonstrable nonsense end of the spectrum. Such beliefs tell us something interesting - not about medicine or illness, but about the power of ignorance and self-deception. They teach us about the futility of testimonials and the need for rigorous science.
Craniosacral therapy (CST) is an excellent example of a practice that is solidly in the demonstrable nonsense zone. The basic claim is that subtle manipulation of the bones of the skull can treat a variety of conditions and symptoms. It is now a classic medical pseudoscience that continues to thrive.
Like many medical pseudosciences, CST was not the product of a collaborative research program by many individuals building on each other's work, but was the flash insight of an individual (a lone genius or lone crank, depending on your perspective). Craniosacraltherapy.org explains:
While examining the bevel-shaped sutures of a sphenoid and temporal bone, Sutherland had an insight which changed the course of his life. He described how a remarkable thought had struck him like a blinding flash of light. He realized that the sutures of the bones he was holding resembled the gills of a fish and were designed for a respiratory motion. He didn’t understand where this idea came from, nor its true significance, but it echoed through his mind.
All of CST is based upon a superficial similarity between gills and the sutures of the skull. The similarity is likely not a coincidence, as both structures evolved to maximize surface area, although for different functions - the gills to exchange gases and the sutures to form a tight connection between adjacent skull bones.
Note, however, the tone of the paragraph above. It is trying to evoke the sense not just of a brilliant insight, but also of a prophetic vision. There is, of course, nothing wrong with flash insights. They play an important role in the advance of science. But as Thomas Edison said, "Genius is one percent inspiration, ninety-nine percent perspiration." The flash of insight is only 1% of scientific advance. The real work is then figuring out a way to test the insight, to see if it is real, and then listening to the evidence.
Cranks generally stop after the flash of insight. Their major malfunction is probably a combination of hubris (seeing themselves as a super-genius or prophet rather than a regular guy with an interesting idea), and a poor grasp of true scientific principles. If they undergo any further experimentation at all it is designed to confirm their insight, not to truly test it.
Osteopath William Garner Sutherland seems to fall into the prophetic crank category, rather than true scientist, and the result is CST.
Sutherland believed that the brain "breathed" with an inherent rhythm that was then transferred to the body:
The inherent life-force of the body, the Breath of Life, was seen by Dr Sutherland to be the animator or spark behind these involuntary rhythms. Alluding to the source of this phenomenon, other practitioners have referred to it as "the soul’s breath in the body". The Breath of Life is considered to carry a subtle yet powerful "potency" or force, which produces subtle rhythms as it is transmitted around the body.
This makes CST one of the many vitalistic practices - based on the vague notion of a life energy or force. Conveniently, none of the basic properties that are claimed for CST can be measured objectively - the movement of the cranial bones, the rhythm of the central nervous system, or the existence of the "inherent life-force." These notions are all unscientific and at odds with modern biology.
In modern times the most prominent proponent of CST was another osteopath, John E. Upledger. Dr. Upledger recently died, but his website is still active, and declares:
CST is a gentle, hands-on method of evaluating and enhancing the functioning of a physiological body system called the craniosacral system - comprised of the membranes and cerebrospinal fluid that surround and protect the brain and spinal cord.
Using a soft touch generally no greater than 5 grams, or about the weight of a nickel, practitioners release restrictions in the craniosacral system to improve the functioning of the central nervous system.
The "craniosacral system" as imagined by Dr. Upledger does not exist. Practitioners of CST use hands on diagnosis, because the rhythms they are feeling (like the energy fields of therapeutic touch) do not exist and cannot be detected by scientific instruments. Further, CST practitioners claim that not only can the fused cranial bones be moved, but they can be manipulated with as little as 5 grams of pressure.
Notice also the standard claims of the "alternative" practitioner - that the intervention supports and enhances the functioning of the body, that it restores balance and rhythm by releasing restrictions or blockages. This is the same language you will encounter with acupuncture, homeopathy, chiropractic, and Reiki - because it's vague, feel-good nonsense.
Yet Upledger's website claims that CST can treat: Migraine Headaches, Chronic Neck, and Back Pain, Motor-Coordination Impairments, Colic, Autism, Central Nervous System Disorders, Orthopedic Problems, Traumatic Brain and Spinal Cord Injuries, Scoliosis, Infantile Disorders, Learning Disabilities, Chronic Fatigue, Emotional Difficulties, Stress and Tension-Related Problems, Fibromyalgia and other Connective-Tissue Disorders, Temporomandibular Joint Syndrome (TMJ), Neurovascular or Immune Disorders, Post-Traumatic Stress Disorder, Post-Surgical Dysfunction.
Sutherland published his first article about CST in the 1930's, so practitioners and proponents have had about 80 years to provide convincing scientific evidence for CTS - that its underlying principles are correct, and that it is an effective treatment for specific conditions. Apparently 80 years has not been enough.
A read of the published peer-reviewed literature does not contain support for CST for any indication, or any of its underlying claims. A 2012 review of CST research concluded:
This review revealed the paucity of CST research in patients with different clinical pathologies. CST assessment is feasible in RCTs and has the potential of providing valuable outcomes to further support clinical decision-making. However, due to the current moderate methodological quality of the included studies, further research is needed.
In other words, there is little CST research and what exists is of low scientific quality. This is inexcusable. There is no legitimate excuse for a modern medical intervention to be used for 80 years without adequate study - especially when the claims are unusual and not generally accepted by the scientific community. This lack of research and broad scope of claims is consistent with medical pseudoscience, not a legitimate treatment.
CST continues to be practiced, mainly by osteopaths, chiropractors, and some physical therapists. I disagree with the reviewer quoted above in that I do not believe CST requires further research. It is demonstrable nonsense that should be discarded as a pseudoscientific idea.
Steven Novella, M.D. is the JREF's Senior Fellow and Director of the JREF’s Science-Based Medicine project.