Depends how early you catch it. We had a filly with a bowed tendon, we kept the leg bandaged snug 24/7. It helped with the bo, and now it'sbarely noticable, however it has gone on a year now. The same goes for splints, If you catch them early enough. Another horse threw a WHOPPER of a splint, we iced him for 3days and then bandaged him 24/7 (except for in work - we used excercise bandages), its been over a year but you can't see the splint unless you know its there.
Comfrey leaves are EXCELLENT for bones, soak them in a bit of warm water and then bandage them around knees, joints, hocks, splints or any other NEW bone deformaties.
Arnica is good for bruising, you can add tablets to the feed or Arnica Oil is a wonderful massage treatment (for people too!!!)
Mint is an appetite stimulant. (fresh or dried)
Hawthorn is good for horses with foot problems.
Yeast for general condition. (In some stallion barns here they add a pint of Guinness to the feed!!! - apparently the Stallions LOVE it

men hahaha)
I've got loads more but can't think of them off hand, but I'll put them up tomorrow!!!

"But i don't want to go among mad people." Said Alice.
"Oh, you can't help that," said the cat. "We're all mad here."