If Mickey’s knees had held up, no telling what he could have done!
While that's true and certainly today's medicine would have rendered his knees a totally different verdict, Mickey's biggest problem was his belief that he would end up like his father and die young so he didn't take care of himself. He admitted as much when he was dying from essentially self-inflicted liver cancer due to years of drinking and other abuse. But yes, what would he have done had his knees been sound his entire career.