I've had several killed or mangled bad enough that they had to be shot running bears.
I had the pleasure of talking with a colorful old coot back in the mountains of SW Virginia. He related a story where his hounds backed a big boar against a rock face. He said the bear killed or maimed almost all of his pack before he got there to shoot it. He quit running bears after that because he didn't have it in him to raise another pack from scratch.