Originally published in Massage Today
June, 2006, Vol. 06, Issue 06

Have you noticed how buzz words and key phrases are emerging from the powers that be in the increasingly regulated application of health care? Evidence-based medicine is one of these and there’s a lot to be said about this topic – but not in this article.

Another phrase that is emerging is informed consent. At its heart, this phrase, and what it entails, simply tells us that patients need to know what a particular form of treatment involves, as well as the drawbacks, possible side effects, success rates, etc.

How could anyone take exception to this you might ask? Surely it’s everyone’s right to know if there is a risk attached to a treatment method, so they can make an informed decision to accept or decline? The risk-benefit ratio can only be considered once the relative benefits, as well as potential risks, are made available to the patient/client in the form of objective information.

I would say the answer to this question is not as clear-cut as it may seem. Let’s look at this in relation to manual forms of treatment. The most invasive form of manual therapy is arguably the high velocity, low amplitude (HVLA) thrust technique, as used by chiropractors, osteopaths and increasingly by physical therapists, to manipulate (adjust) joints.

Many experts have suggested there are risks attached to this form of treatment,1 particularly when applied in the cervical region. The most serious possible negative effect is stated as being a risk of stroke (vertebral artery dissection). The problem with the statistics used to demonstrate damage from manipulation of this sort is that they seldom make clear just what type of manipulation is involved, and they seldom describe the competence of the individuals applying the manipulation.

Gibbon and Tehan,2 in regards to this very issue, report that in a study of Australian Manipulative Physiotherapists, who are required to undertake specific postgraduate study in manipulative therapy, there were no major complications in 4,601 physiotherapist years of manipulative practice. Despite allegations3 the evidence actually is that a causal connection between cervical HVLT manipulation and subsequent stroke is unproven, and when applied carefully the risk is virtually nil.4,5

To be absolutely clear, there are risks in all treatment (even massage), but these risks reduce to the point where they become statistically invisible when the methods are used safely, by well-trained people, in the correct situation (for the patient)! But in the informed consent model, every patient about to receive such treatment would need to be informed that there is a defined and explained risk (and in some countries would be required to sign a form saying they had been informed, and have consented to the treatment).6 Ask yourself whether such a protocol is likely to be conducive to the individual staying calm and relaxed during the procedure? In many instances is it not likely to result in a refusal of extremely effective modes of treatment?

Despite these reservations, I am bound (in the U.K.), by a legal requirement to obtain such informed consent before manipulating any part of the body. This also is true of application of soft tissue manipulation methods, including muscle energy techniques and neuromuscular techniques. And all this takes valuable (to the patient and to me) time, and creates (I believe) unnecessary bureaucratic management burdens, as well as anxiety for the patient.

This preamble brings me to what I really wanted to discuss in this article – the meaning of symptoms, including “reactions” to treatment (such as soft tissue manipulation). I would imagine there is very little disagreement with the basic premise that all healing is endogenous (i.e., the body is self-regulating and treatment, of whatever sort, is designed to either enhance that process or to remove obstacles to it). All treatment of the body demands an adaptive response.

Whether the response is helpful and health-enhancing or not, depends on whether it’s appropriate for that particular individual/condition, at that particular time.

If a “therapeutic response” is forthcoming following treatment – manual or otherwise – there is bound to be some degree of a sense of change, as homeostatic modifications work their way through the systems, and these likely are to be reported as “symptoms,” or “reactions.”

In many therapeutic traditions, a “therapeutic response” is regarded as desirable, as evidence of self-regulating processes in action. It’s easy enough to recognize that without inflammation, we would not recover from injury (and also that excessive or inappropriate inflammation is harmful). It’s also not hard to grasp the idea that if you have ingested contaminated food, the rather undignified and unpleasant symptoms of vomiting and diarrhea are life-savers (or that excessive elimination of these types can be dangerous).

Understanding that effects of (or reactions to) treatment might fall into the category of “good symptoms” should be something that can easily be explained to patients. In homeopathy, the “law of cure” suggests that recovery of health occurs in a reverse order, so the most recent symptoms are likely to be the first to go. Reactions and response to homeopathic remedies are therefore keenly assessed and are seen as positive indications of healing in process. In naturopathy, the self-regulating responses looked for as treatment is initiated (e.g., fasting, nutritional reform or supplementation, botanical medicine, hydrotherapy, physical medicine) are thought of as being representative of the “healing power of nature.” These changes are commonly eliminative, and are not considered to be “side effects” but are evidence of healing in action.

In chiropractic and osteopathy, similar processes to those mentioned in the homeopathy discussion may occur, as symptoms reappear and are then normalized by the body itself, in reverse order to their original appearance. In many forms of psychotherapy, and in somatic branches of those methods such as somatic experiencing, reintegration of dysfunctional adaptive states might well involve the reappearance of symptoms as part of the process of normalization, discharge of the effects of trauma, and restoration of health. These “side effects” are not side effects at all but signify change, part of the body/mind’s adaptation towards a more balanced state.

In the “informed consent” model, we likely are to spend a great deal of time having to explain these concepts. My main concern is that people might not grasp the concept of “symptoms being good for you” or “symptoms as evidence of healing in action,” and might decline what they need most once they have been “informed.” Even worse, having been informed there is a risk of stroke following manipulation of the neck, what will go through a person’s mind when normal responses to treatment such as deep tissue massage, or neuro-muscular technique, or trigger point deactivation, or muscle energy stretching (a degree of discomfort for 24 hours for example, or a slight degree of light-headedness perhaps) are experienced? A phone call to me (or you) at 2 a.m. might be the patient’s reaction. I’m not sure what mine will be when that happens though. What do you think?


  1. LeBoeuf-Yde C et al. Side effects of chiropractic treatment J Manip Physiol. Ther. 1997, 20:511-515.
  2. Gibbons P Tehan P HVLA Thrust techniques: What are the risks? International J Osteopathic Medicine, 2006 9:4-12.
  3. Cagnie B Vinck E et al. How common are side effects of spinal manipulation and can these be predicted. Manual Therapy 2004, 9:151-156.
  4. Breen A Manipulation of the Neck and stroke-time for more rigorous evidence Med J Australia, 2002, 176:364-365.
  5. Rivett D Neurovascular comprtomiser complicating cervical spine manipulation. J Manual Manipulative Ther. 1995, 3:144-151.
  6. Clubb D Cervical manipulation and vertebral artewry injury. A literature review. Jnl Manual Manipulative Ther. 2002, 10:11-16.