I can't speak to Murray, but for me I was playing in a tournament and ruptured 2 discs in my lower back.
No matter how hard I worked I was never the same and my career was on the clock.
After that I was in a cycle of play a season or two -> tweak the injury again -> 3 months of rehab -> play a season or two -> tweak the injury again -> 3 months of rehab and eventually body and mind just erodes until you arent even close to the same goalie because in the back of your mind every single save could be the one that puts you back on the shelf. I played about 5-6 years where I was not the same goalie - sure i'd have brief stretches where i could hit that level again, and even won a title, but it was always a time bomb.
As a non pro I hung on to the game way longer than I should have, I can only imagine how battered some of these guys must be and what they must be going through to stay in the game.