Take Rocky OFF commercial kibble. Put him on Raw. Nature's Variety is sold in a lot of pet food supply shops and is Frozen Raw. It is already formulated with veggies and bones and comes in small frozen medallions or larger frozen patties. They also have raw bones. His diet is the weakest link right now and should be changed. You can also supplement with organic free range eggs. My dog, for instance, gets a couple of eggs, half a can of either wild salmon or mackerel and about a 1/4 cup of cottage cheese for breakfast and gets Nature's Variety thawed raw chicken medallions and some thawed dark green veggie like kale, mustard, or turnip and a dose of cod liver oil or calves or chicken livers for dinner.
If Rocky is cooperative, you can try a castor oil pack nightly on his leg. You should do it for several weeks. I'd give Rocky more than one ounce daily. I'd put at least 1/2 cup to 1 cup in his water bowl daily.