The perceived benefit from procedures like arthroscopic knee surgery, vertebral cement injections, shoulder procedures, and stenting for chronic stable angina is primarily due to the psychological stimulus of the intervention, not the intervention itself.

“it's not the debridement per se it's the psychological stimulus of having that done and this is true for injecting polyacrylamide cement into osteoporotic fractures of the vertebra it's true for a couple of shoulder procedures it's true for i believe stenting chronic stable angina”