[Placebo surgery: surprises and ethical questions]

Placebo has a well-known therapeutic potential and this explains why placebo-controlled trials are considered necessary for showing the efficacy (and to a lesser extent the safety) of a new drug treatment. However, there are clear examples of a potent surgical placebo-effect in several pathological fields (cardiology, osteoarthropathy, slipped disk, post-traumatic lesions, abdominal adhesions, Parkinson's disease). The efficacy of the placebo surgery would suggest the advisability of placebo-controlled studies also for some surgical treatments. This type of trials, however, raises a number of reservations and ethical questions. In particular, it is necessary to consider the possible unethical nature of placebo surgery as against the unethical nature of surgical operations lacking any evidence of "specific" efficacy (i.e. being better than placebo).