I've always had knee problems in the past, but usually it is cartlidge involved...
I was at the rave enjoying myself saturday night when I guess I spun on my leg wrong and all of a sudden my kneecap was twisted up and not looking anything like a knee is supposed to look, I had a bit to drink so I wasn't really feeling much pain.
Either way, I believe one of the staff members came over and relocated it and a wheel chair seemed to be following shortly there after. It seemed like a matter of minutes, to which I later confirmed it was.
That was really awesome, I can't believe how fa