You go in when the risk of the operation is lower than the pain of not getting it. A new knee is major surgery, but not without risk.
I recently requested a stress test from my Dr at the VA. I have no symptoms, I just wanted one to see if I had something that I could fix before it's too late. The Dr said no, because if they find something, they will fix it. Otherwise, why go?
If I need a stent, there is a 2% chance or dying. And I willing to take the risk, when I have no symptoms now?
FIRE no later than 7/5/2016
at 56 (done), securing '16 401K match (done), getting '15 401K match (done), LTI Bonus (done), Perf bonus (done), maxing out 401K (done), picking up 1,000 hours to get another year of pension (done), July 1st benefits (vacation day, healthcare) (done), July 4th holiday. 0 days left. (done) OFFICIALLY RETIRED 7/5/2016!!