So the rpg's premise is that sleeping kills you, and you, with other characters, are trying to stay awake, while fighting off the horrors.
Anyways, a character getting injuries doesn't translate well to the health system, which is mostly tracking fatigue, and your likelihood of sleeping. The health system does not track physical health. As of now, the health system doesn't directly affect your ability to complete tasks. So I think that having injuries as a sort of condition based system that lowers the chances of success for certain actions would be the best way.
The two things I want to hear suggestions on the most is a system for the character to be impeded by injuries, and a system to resolve those injuries.
To help with the first point, the current action resolution is by rolling dice pools, sized from 1d6 to 5d6, depending on the stat used in the action. If you get any sixes, then the action succeeds. I will adjust this eventually, since the probablity of success is pretty low as it stands right now.