I tore some stuff in mine, I have the medical report somewhere at home. Forget now.
But the only option given to me was surgery. I didn't want surgery. And not to scare you, but it scared the crap out of me. My cousin who was 23 went in for a standard knee surgery, she got out of the hospital and fell over dead with a blood clot. I said no surgery for me!
Squatting about killed me, omg. I'd have to fall over, straighten my leg back out, and lay there before trying to get back up. I babied it for over a year. Watching what I was doing, moving carefully, not running(which wasn't hard to avoid). Now its fine. Only bothers me when its REALLY damp out, or REALLY cold.