According to Wikipedia, Gua sha involves repeated pressured strokes over lubricated skin with a smooth edge placed against the pre-oiled skin surface, pressed down firmly, and then moved downwards along muscles or meridians.This intervention causes bleeding from capillaries and sub-cutaneous blemishing which usually last for several days. According to a recent article on Gua Sha, it is a traditional healing technique popular in Asia and Asian immigrant communities involving unidirectional scraping and scratching of the skin until ‘Sha-blemishes’ appear.
Gua Sha paractitioners make far-reaching therapeutic claims, e.g.” Gua Sha is used whenever a patient has pain whether associated with an acute or chronic disorder… In addition to resolving musculo skeletal pain, Gua Sha is used to treat as well as prevent common cold, flu, bronchitis, asthma, as well as any chronic disorder involving pain, congestion of Qi and Blood“. Another source informs us that ” Gua Sha is performed to treat systemic toxicity, poor circulation, physical and emotional stress, and migraines. Gua Sha healing promotes the flow of Qi (energy) and blood throughout the body for overall health“.
Gua Sha “blemishes” can look frightful – more like the result of torture than of treatment. Yet with our current craze for all things exotic in medicine, Gua Sha is becoming popular also in Western countries. One German team has even published several RCTs of Gua Sha.
This group treated 40 patients with neck pain either with Gua Sha or locally applied heat packs. They found that, after one week, the pain was significantly reduced in the former compared to the latter group. The same team also published a study with 40 back or neck-pain patients who either received a single session of Gua Sha or were left untreated. The results indicate that one week later, the treated patients had less pain than the untreated ones.
My favoutite article on the subject must be a case report by the same German research team. It describes a woman suffering from chronic headaches. She was treated with a range of interventions, including Gua Sha – and her symptoms improved. From this course of events, the authors conclude that “this case provides first evidence that Gua Sha is effective in the treatment of headaches”
The truth, of course, is that neither this case nor the two RCTs provide any good evidence at all. The case-report is, in fact, a classic example of drawing hilariously over-optimistic conclusions from data that are everything but conclusive. And the two RCTs just show how remarkable placebo-effects can be, particularly if the treatment is exotic, impressive, involves physical touch, is slightly painful and raises high expectations.
My explanation for the observed effects after Gua Sha is quite simple: imagine you have a headache and accidentally injure yourself – say you fall off your bike and the tarmac scrapes off an area of skin on your thigh. This hurts quite a bit and distracts you from your headache, perhaps even to such an extend that you do not feel it any more. As the wound heals, it gets a bit infected and thus hurts for several days; chances are that your headache will be gone for that period of time. Of course, the Gua Sha- effect would be larger because the factors mentioned above (exotic treatment, expectation etc.) but essentially the accident and the treatment work via similar mechanisms, namely distraction and counter-irritation. And neither Gua Sha nor injuring yourself on the tarmac are truly recommendable therapies, in my view.
But surely, for the patient, it does not matter how she gets rid of her headache! The main point is that Gua Sha works! In a way, this attitude is understandable – except, we do not need the hocus pocus of meridians, qi, TCM, ancient wisdom etc. nor do we need to tolerate claims that Gua Sha is “serious medicine” and has any specific effects whatsoever. All we do need is to apply some common sense and then use any other method of therapeutic counter-irritation; that might be more honest, safer and would roughly do the same trick.
No, I am wrong! I forgot something important: it would not be nearly as lucrative for the TCM-practitioner.