Very interesting research. Thank you, but you can most likely do far better yourself, as I got that quotation after only about 30 seconds of searching online. A more time-intensive search will provide much better information.
I can only imagine that the quote of $4000 to $6000 is only for the actual hip. It's the extras that mount up - anesthetist, post op. care, hospital stay; pain meds. etc.
If that's true, then the company posting those figures is nothing more than a pack of liars and thieves, which of course may be true.
I think there is at least one zero missing from that figure of $6000.
Let's hope not! A hip replacement without complications shouldn't be "that" bad.
However, if it is correct, please share your source as I have a friend about to have both hips replaced and she would love to have the jobs done for $12,000.