Cats instintfully go for a spine bite. They don't always break it, but they damage enough nerves to cripple.
I had a BIG long haired yellow Tom cat. He was a railer. Couple of teeth snapped short and scars all over his face and ears.
He got older, but not smarter. He ran across a younger, faster cat that put a full four fang bite around two inches up from the base of his tail. He dragged himself home by his front legs. I'd prop him up so he could eat and drink, and clean him up when he relived himself. Did that a for a couple of weeks and seriously debated about giving him a long rifle to the ear. Just about the time I had hardened my heart enough to do it, he actually got up and pogoed on his hine legs. A couple months of that, and he could walk, but not very good. A few months later and he was doing fine, but his fighting days were over.
Eight deer out back tonight. They've gone though 50 pounds of corn in the last three days. Sure is good to see 'em back.