Ethical issues and doubts surrounding the acceptability of sham surgery.

Sham surgery omits the intended therapeutic procedure and aims instead to isolate the specific effects of a surgical treatment as opposed to any incidental effects, thus neutralizing the placebo effect. Sham controls have been used in many surgical trials: bilateral internal mammary artery ligation, arthroscopic procedures and transplantation of human embryonic stem cell-derived neurons in patients with Parkinson's disease. However, this experimental approach poses considerable problems for medical ethics and codes of professional conduct. Exposure to an invasive sham procedure is not without risk and can cause pain and suffering, without offering any of the advantages associated with the treatment. Moreover, what does freely given informed consent entail for patients who agree to participate in such trials? The ethical validity of placebo-controlled clinical trials is still under discussion in the international scientific community. In this paper, we argue that the use of sham surgery is unacceptable because it is invasive and dangerous and may cause physical and psychological harm.