Sorry - have to give the ecological side again - to put it harshly, the only way that this site will stop growing is if we abandon all our social support systems and we become individually dependant on total health to gather resources in sufficient abundance to have offspring and raise them to reproductive age. Then, having a bum knee might negatively affect our ability to pass on our genes, and natural selection shouldl favour those with strong knees. Eventually, the knee should evolve into a better joint. It may take quite a few hundred thousand years or more, but that would be the evolutionary opinion.
I for one will suffer the badly designed knee and enjoy the social support!
Mirek (with tongue planted firmly in cheek)