I was a couple hours into skating at the local park when I decided to break out my little launch ramp ( only 2' high ). After a few tries of just ollieing into a little air, I screwed up royally. Landed with my back foot ( I skate goofy ) off the tail, but front foot still firmly on the board. Heard my knee pop as it went into hyperextension and maybe worse. Waited about 30 minutes to try to shake it off, got back on my board and went to push with the damaged knee. It bent too far forward again and collapsed. I went home, iced that mother down for a day and 1/2, ate handfuls of ibuprofen and broke out the old knee brace and crutches. Set an appointment with the orthopedic doc this morning. I am hoping that I did not wreck my PCL or ( noooooo! ) my ACL. I have had this knee fixed twice ( everything but the ACL ) and it was never as bad an injury as I got this time. Lesson of the day. Launch ramps are for young knees, not 42 year old knees.