Oh yeah and about how to prevent knee injuries that was a good point by blackened. If you ride in chop get a medium to soft flex board. Non carbon. Makes a huge difference.
Don't look at pros as an example. They push limits and getting seriously hurt is part of the game. I also had ACL surgery. Broke both of my ankles. Twice. And almost all my toes. Ribs, shoulder, back and so on. But they heal. Im still kiting and biking strong in my late 40s.
If you are a casual rider non of these can probably happen to you, but on the other hand, you are human. You break. You heal. Its part of the game. Accept it. Digg it. You are excercising an extreme sport. Things can go wrong.
Do you drive a car? I guess yes, so you know you have more chances of getting serioussly hurt in a car accident or even die, right? You drive everyday? Just saying