Torn a few knee ligaments in my day as well. I know where you are coming from there. Also herniated a disk in my lower back while drunk. Not fun.
I did the 'run through field then drop on one knee' thing onto a rock while training.
Ouch.
The other knee was repeatedly hit with the edge of a car door because the 'lady' opoeniong the door thought it was funny to do so.
She thought it was funny until she had it done to her.
She no longer hits me in the knee with the car door when I am trying to be polite and open the door for her.