I see these celebrations often and in every sport. These are professional players that are extremely passionate about what they do and sometimes they get caught up in the moment. I usually cringe when I see these types of celebrations due to risk of injury and yes, sometimes the players get hurt. It happens. Accidents happen.
Pet peeve of mine, too. While coaching high school softball, you'd run into this sort of horseplay every now and than, and I (atypically, I might add) would bark pretty loudly at the instigator. Why? Because this particular high school team had two, count 'em, two all-conference players injured late in the season over the previous five years, doing this sort of nonsense.
Neither injury was long-term, but, in both cases, it hurt the team short-term. Since players' time on a high-school varsity team is usually no more than two or three years, the kids don't remember what happened three, four, five years ago: coaches do.
