Often the tendon will appear lumpy, there may be some minor swelling and the horse could be a little lame or severely lame. If they bow the tendon, it will appear that the tendow is arched backwards from the knee.
Bandage bruising will come up either as tender spots, patches of missing hair, and can get to the point of open, weeping wounds. You want to avoid bandage bruising at all costs, it is a horror to get rid of.
I use open fronted tendon boots, which are desgined to support the tendons but also offer some protection from brushing. I add bell boots for jumping and fast work.
I'm trying to wean his owner off she sheepkin liners as his legs get so hot by the time you take the boots off! I also always make sure the boots are the last things on and the first things off.
At home, my horse wears brushing boots every time we ride, and when we compete cross country he wears fetlock boots on his fronts too. When competing on the flat he doesn't tend to wear anything, or for working hunter or show jumping, although I would consider getting a nice pair of tendon boots for show jumping in the future.