Worst physical injuries

I've had a few pretty painful experiences. We have a fence of pine trees behind our house in the yard, and when I was about 12 I used to climb around in those things for fun. Decided to try and get higher up in the branches and go through the trees since they were close together. At about 30 feet off the ground, the branch I was on snapped and dropped me on every branch going down the tree which promptly broke under my weight. Knocked the wind out of me and nearly broke both my legs when I slammed them on the lowest branch which basically tried to bend them backwards. My parents were amazed I hadn't been killed because I landed on a nasty rock. Thankfully it didn't break anything in my back otherwise I could have been paralyzed.

Another painful memory would be when I was finished edging our lawn with our convertable tiller. I was changing out the blades and had to turn the machine around to do this. After a minute pulling the pins out and taking the blades off I smelled something burning, and when I looked I noticed that my knee was on the muffler and had singed off most of the skin over the bone. Thankfully it wasn't serious enough that I required going to the hospital, but I had to clean out the wound and keep it covered for over a few weeks while the skin regrew. It's never fun to smell your own flesh burning.

Jam it back in, in the dark.