I believe it is a typo and should be 'Leo the lion was confined to a cage that was too small and had an open, infected wound on his nose.' This means that there was an open wound on Leo's nose that was infected.

This is not correct English. I don't know who wrote that, but he/she is not a native English speaker or it is a misprint. There is no such expression in English. It maybe that it was supposed to be, "and had an open wound on his nose."

Manzana, read it again please. You are saying "gave an open" the sentence as written above says, "hand an open." So you are saying that it is correct and then changing it.

If that was true manzana it would have been wrote '... which handed an open infected wound, on his nose' as to hand is present tense, when it's talking about past tense. But this is also is wrong as it's talking about a wound which has had the time to become infected, meaning it already existed.

Hmm....