Oh, where to begin.
Lessee…
Must have been about 10. Was trying to take the broken pedal off my bike and it wouldn’t cooperate. I got really pissed and figured I needed to break it off. I looked for a sledgehammer, but not finding one, I used the next closest thing; a splitting maul. for the uninformed, it looks like a sledgehammer on one end and an axe on the other. I hit it, and it promptly bounced back into my knee – right to the bone.
At Boy Scout camp, my bunkmate in the tent left his swiss army knife open on his bed. I heard a noise outside, and jumped on his bunk to lok out the tent flap. Got a nice ride to the local hospital for that one, and two stitches in my left knee. Looks like a little alligator.
Then, I had just gotten my very own swiss army knife for my birthday a few months prior. My parents were in the other room, and I decided I wanted tocarve the back of the pumpkin on the windowsill. Unfortunately, the pumpkin was mostly rotten and I put too much force into it. I’ve got a nice scar above my left knee from that one.
There was the time I was in high school, and riding a bike no handed as I had done many times before. Except this time, I decided I needed to take my sweatshirt off. Again, which I had done many times before while riding no-handed. Except this time, this sweatshirt sleeve promptly got caught in the front wheel, which decided to stop moving. I went head over heels and slammed down on my forearms. They were tingly for a week.
Or the time I was in college, climbing a tree to take an aerial view of my girlfriend. I was about 40 feet up standing between two trees, when one limb snapped. Down I went through all the tree branches, slamming flat on my back. When I came to, I looked over to my right and there was an iron pipe sticking out of the ground not a foot away. I walked hunched over for a week, and have a nice scar on my @ss from it.
Also in college, I was working at a restaurant. When the trash can got full, we always climbed up and jumped onit to push it down. This time, it was too close to the vent hood for the fryers and when I jumped up I hit my head. Didn’t think much of it, till I touched it and it was bleeding. A LOT. It bled for about a week, off and on. Didn’t bother with the hospital. Got a bump and a scar from that one.
Playing with my four wheeler, I got too close to the edge of a ravine and it rolled over. Many times. I was thrown free after it rolled over me twice. I got up, swearing, and rolled it right side up and rode it back up the hill.
Snowstorm. Driving my old 2wd Toyota truck. Slipped on the ice, the truck spun, caught the soft shoulder, and rolled. When I came to, I was upside down. Had to get out my Leatherman ™ and cut my seatbelt, crashing down on the roof. Have a nice scar on my head form that one, too.
We were building an addition onto the house. There was a piece of plywood with a few boards underneath that was serving as a set of stairs / ramp. I walked up it barefoot, as I had done many times before. This time, however there was a lot of sand on the plywood. My left foot slipped and the top of my foot ran down the edge of the plywood, opening up my foot for four inches ina nice jagged pattern. Thank god for butterfly bandages. I’ve got a good scar from that one too.
Of course, I saved the best for last. I was cutting down small saplings with my cousin on his new property, as we’d done before; 3-4 inch trees. So you sort of slash with the chainsaw and go onto the next one. We were making good progress until the wind suddenly picked up, and the tree I was cutting bent back, kicking the running chainsaw into my right knee. Severed several tendons and cut meat out completely down to the bone. Ever cut a log with a chainsaw and stop about halfway? that nice 3/8" gap it leaves where there was once wood? That was my knee. The Dr. wouldn’t let me look at it, but when he left the room, I did 
I’ve got a nice scar on my knee and bone growth that looks like a second kneecap slightly below the first. The Dr.'s said I’d never gain full mobility again. WRONG. I’d counter that it can handle at least as much weight as my"good" knee.
I think that’s about it. It’s amazing I’m still alive, as I’m so accident prone.