Behind the kid with the amputated leg....I have had some pretty good ones....
My big bro quadrupple bounced me, and on the 4th I came down on the rim with my heel, shattered my ankle.
Landed in the springs on a big spin, now I have a permanent crease in my heel bone...i can feel it if i roll my foot back and forth
Finally, the doozie:  Training on professional Trampolines, going literally about 20 feet above the bed, doing HUGE backflips....it was late in the training session and I decided to stop.  But, when I went to stop bouncing, the rebound in the trampoline sent me about 10 feet in the air because I did not do it right.  In the air, i kept flipping farther and farther back, and came down with 100% of my weight on the back of my neck...i couldn't do anything about it.  My whole body went numb, and I couldn't feel a thing for about a minute and a half.  I couldn't move, open my eyes, everything just went black.  Everyone thought I had broken my neck. Luckly, all feeling soon came back and I could move again.  I got up, and sat in a chair, but literally could not move my neck.  Couldn't move my neck for 3 weeks, but I still can walk....so I am thankful!