I would say that Noah has had more flukes, than just being injury prone. Big men rarely make 82 games, so any big that can make it 70+ games a year without some reoccurring injury is pretty damn healthy in my book. Thats exactly where I expect Joakim to be for the next so many years of his career, between 70-80 games played.
Roy though, it's not about being injury prone. Roy's career is pretty much over. There's a big difference there IMO. He's going to come back again, give it a try, have a few solid games, but get hurt again. Unfortunately sports medicine isn't quite that advanced to save his career