For what it is worth, I blew my left knee apart in 1975... The Dr wanted to amputate. My mother signed a form to allow be it but convinced the Dr to rebuild it and if it still needed to be amputated we would do it later.
After 9 months in a cast from the waist down (over the foot)... the Dr's said, I was lucky that my leg was saved but prepared me saying that I would be unable to walk by 30 and that I would never regain full mobility. 6 Months after the removal of the cast, I had 90 percent mobility...1 year 100 percent. Needless to say, 35 years later I am still bowling 100 percent, still full range of motion and very limited problems.
I think I was lucky. But, I was determined at 15 that it was not going to happen to me. I worked like a mad dog to rehabilitate my leg. I think the Dr's prepare everyone for the worst situation possible and then when things go better everyone is happy. I hardly followed the Dr's advice thats why I think I was lucky. But then I wonder if I had what would have been the outcome.
I wish you all the luck but you dont have to leave the game. You coach, you take your knowledge and share it. Mentor. Your profile speaks to a great bowler... teach what that means.