Youre right, he didnt deserve to get his ankle broken. What he actually deserved was to have both his legs broken, leaving him with a life long limp and a constant reminder of just how big a (insert various words) he is.
He walked upto a kid, and punched him in the face, for no reason. Im certainly against violence, but im even more against bullying. He had every right to snap, who knows how many times he has had to put up with that kind of thing happening. The little scrat deserved everything he got, and to be honest...although dropping someone like that is dangerous, the bullied kid was hardly thinking about that at the time, and nor should he have to. If im totally honest, I dont think I would feel sympathetic in the slightest if the kid had been paralysed.
I hope the bullied kid can finally get on and just enjoy his days at school without the constant worry of waking up every morning!