Ethical issues in the design of randomized trials: to sham or not to sham.

The placebo effect is based on the expectations of the patient regarding the effectiveness of the treatment. The high levels of stress and rituals involved with surgery can lead to a strong placebo effect. However, the ethical principles of performing sham surgery to measure any placebo effect have been questioned, and sham-controlled surgical trials are rarely conducted. While there are a number of ethical principles that must be considered to justify the implementation of a sham-controlled surgical clinical trial, four areas deserve particular attention: equipoise, risk minimization, informed consent, and deception. Particularly in orthopaedics, where equipoise is common, sham-controlled trials may be important to ensure that inferior or ineffective treatments do not become standard practice.