The closest I got to breaking a bone is when I landed my left elbow hard when I was in grade school. We were playing tag, I slipped and fell elbow-first on hard concrete. I heard a pop and a slight crack. When I looked at my left arm, I was horrified to see that it was almost hanging loose from my elbow and it was in a weird position.
When we reached the nearest hospital, the doctor's diagnosis and x-rays revealed I almost completely tore off my tendon (about half of it was torn already), left arm dislocation, bone splinters in the elbow area, and slight cracks were visible on some lower areas of the bones closest to the left elbow.
It took me 9 months to regain my left arm's mobility, and 6 months more before I was able to carry heavy things with my left hand.