A dislocated elbow: a player jumped to rebound, lost his balance and fell just on his elbow. Terrible to see. I said to just cover him and call an ambulance.
It was before a doctor was required at every major game in Italy; some leagues now require also an ambulance with a defibrillator.
Another strange injury was to my partner in a wheelchair basketball game: his foot went under a wheel.
He couldn't finish the game, but fortunately he had no big damage. I learnt how painful it can be: don't try.
Ciao