Opaque pricing is reducing competition and increasing the prices of artificial joints. Surgeons are being paid by joint manufacturers rather than by patients, whose interest do you think they will be acting in? Who are they really working for?
I predict that if the sales rep/surgeon relationship can be excised, the cost of surgeons will rise, but by less than the cost of joints will go down. Prices will reflect the opportunity cost of surgeons and the actual cost of joints, rather than the convoluted relationships between doctor and supplier.