Right wrist: I was 2 and my parents were swinging me over a puddle. My wrist got pulled out of its socket. I don't remember it happening, but I do remember the splinty cast thing I had to wear and that I used to bang it on stuff.
Left arm and wrist: Early 1997, I was 11 years old, and I was sleeping over my gram and pop's house. I was walking down the steps and I missed a step at the bottom, and fell. My left arm was extended, elbow locked, and I landed on my hand. The pain shot right through me but I thought it was just a sprain, so pop and I wrapped it and iced it and I was fine.
I went to see STAR WARS in theaters the next day, for the 20th anniversary. My mom, brother, and I were in line for like an hour and a half lulz, and my brother and I were fighting and he hit my arm or something. It hurt more after that, and we went home and had dinner after the movie, then I asked my mom to take me to the hospital. Turns out a couple growth plates in my wrist were broken, as well as one of the bones in my lower arm (I forget which one). Had a purple cast up to my bicep.
Right arm: Summer/fall of 2007. I'm at a local park with two of my closest friends. It's being remodeled and there's a pile of dirt in one section. These little 9-ish year old boys are jumping it with their bikes. So my friends and I are all like, "we're bigger than them, we can do that too." We decide that I'll go first.
Yeah I don't know if I picked up too much speed or what, but I sailed right off the top of that pile, lost my bike in mid air, landed on the basketball court, slid a couple feet, then my bike landed on top of me. The first thing that hurt was my hip, because I scraped all up and down my right side. But when I tried to use my right arm to help me up, I knew it was broken. One of my friends lived across the street and we went over and I called my dad to take me to the hospital. He laughed at me.

Yellow cast up to my elbow, so at least I could still bend my arm this time! I was also able to slide the cast off to scratch and wash my arm because I had pulled a bunch of the padding out after my arm swelled.
I've also had two concussions, once from falling down the stairs when I was like 16 or 17, and once sometime when I was a kid. But I've NEVER had stitches!!