Chicken Attacked, Now Limps

[Dimetrex]

A month ago I checked on my flock to find my alpha rooster lying on the ground next to the fence. He was missing some feathers, had his comb dripping in blood, and could not stand on his otherwise unaltered leg. After I gave him some antibiotics and separated him from the rest, I investigated the scene. He had scratches and bites on his body, corresponding with the blood on the side of the fence. Also, the gamma male had blood on his claws and beak but was not hurt. I hypothesize the alpha was attacked by some animal through the fence, lamed, and the other rooster took advantage of it and tried to fight him.
Within a day of the attack the hurt rooster could stand, and a week later his wounds had nearly healed. Now, a month later, he has made no more improvement. He can walk, but prefers not to, and he has quite a limp.
What might have happened to him, and what should I do? I am feeding him part adult feed, part chick feed for protien. He is inside the house in two large cages, so he can walk about if he likes. His leg was and is not dislocated, and he hates it when I touch the leg. That's all I know as far as the leg goes.