Filipino martial arts/Japanese Karate/Budo crossover. Defense against a stick with an injured arm.

What do you do if you hurt your arm in a fight? And the other guy has a stick, "protest sign", skateboard, etc?

Here's one option. It's not an ideal situation and you have to act fast once you stop the power of the swing.

This is a common defense in many arts. Here, you can see some crossover between eskrima and budo.