I haven't although it's likely my shoulder will need done at some point, it's been a problem forever (cracked the socket aged 15, it healed slightly "too big" so dislocates easily and will probably deteriorate more at some point). Also still likely to need my ankle fused at some point

.
A friend of mine had both knees done really young (about 22) and is likely to need them replaced a few times over her lifespan.
As Slim says, the physio/rehab being good is as important as the operation going well, if not moreso... and takes some discipline to keep it going properly. I've had physio exercises for my foot since October, I do them most days but honestly not as often as I should, and if I neglect it even for a day I end up with pain/discomfort (above and beyond the usual).