I have an 88 year old friend that had both knees replaced. First one and about 10 years later, the other. The first wore out after 20 something years and was replaced. He got a nose bleed, went to the hospital and they patched him up but gave him an infection. Had to pull the last replaced knee out and put cement in for 4 months until the infection cleared up. They put a new knee in and in less than a year, he has another infection. Now they say they can't clear it up with the knee in and can't do another knee because there isn't enough bone left and way to much scarring, the leg has to go if the infection doesn't clear up. So far, everyone he's been to says it won't clear up with the knee in and he is going from specialist to specialist trying to save his leg. 88 and morbidly obese isn't a winning combo here. I think The Cleveland Clinic is his next stop, thank God he is rich and has the resources but it doesn't look good even with that.