The art of medicine in treating osteoarthritis: I will please.

The Latin word placebo literally means, ‘‘I will please’’. Until 1945 the placebo was a ‘‘morally’’ useful but innocuous management tool without curative or symptomatic consequences. When in the 1950s the double-blind randomised controlled trial (RCT) began to establish itself, the placebo was imbued with powerful therapeutic effects and its ethical use in clinical practice was being questioned. In a few years the placebo changed from what was called the ‘‘humble humbug’’ (a means of reinforcing a patient’s confidence in his recovery) to an entity with occult-like powers that could mimic potent drugs. Nowadays placebo is primarily used within the RCT setting; use in clinical practice is generally considered unethical. In the current literature placebo is described as ‘‘inert’’, ‘‘inactive’’ or ‘‘nonspecific’’ and as ‘‘dummy’’ or ‘‘sham’’ treatment in the context of a RCT. An ‘‘active’’ treatment not expected to be useful for the complaints at hand, however, might work on the same principal. When we ask experienced doctors for their opinion on observed placebo effect we receive quite some contradictory responses. Conflicting explanations such as expectation, anxiety relief, faith, patient–doctor relationship, self-perceptions, classic conditioning, symbolic processes, holistic approach, fraud and tricking patients are mentioned among others.