Bruce,

>>from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1888585/

That article references the difficulty of randomized/double blind trials in Orthopedic surgery. The authors use the term "sham surgery" to describe those who get an incision but no actual intervention as part of a randomized trial.

My question would be: if your shoulder pain and disability is bad enough to cause you to want surgery, how content are you to risk being in the sham cohort that doesn't actually get anything done at surgery? Or, if your hip pain is so severe that you want it replaced- will you risk being in the sham cohort who gets an incision and nothing else?

Ethicists cite Godwin's law re the concept of withholding a hip replacement from an old lady in pain, especially when she becomes bed bound and dies when she might have enjoyed another decade in her garden with a proper prosthesis. If you were the surgeon- could you do it?

Since this 2006 paper, minimally invasive surgery has grown substantially and it is far more feasible to perform a sham during an arthroscopy than to withhold a hip replacement from the old lady in pain. IOW for arthroscopy there *is* sham surgery underway yielding extremely useful results. E.g. we know that arthroscopy for osteoarthritis makes little if any difference. The result in the US is that arthroscopy for this purpose is not funded by insurance. IOW it is happening where ethically and professionally possible. For other interventions where double blind is not feasible, long-term research is performed. E.g. many nations have a joint registry that records the outcomes of joint replacements over decades. Whether double blind or not, there is no way to determine longevity of a prosthesis in a human without inserting it- but that is not "trial and error" as might be seen trying to solve a computing problem. It's a body of evidence from patients who almost always experience substantial benefit, but some of whose implants last longer than others.