Consider LASIK eye surgery. That is a medical prodecure that is handled somewhat through the market place. Since it's been done that way, it's become routine, the quality has improved, and the prices have fallen.
If that can be done for eye surgery, there's no reason it can't be done for knee surgery or heart surgery or any other medical prodecure -- other than people, who have a disdain for the marketplace, standing in the way of it.