Because of spawns being limited for sticks or morphine, I suggest that some close quarters weapons could be used instead of sticks to craft a splint (baseball bats, maybe axes because the handle could be used). This would mean that a fracture wouldn't result in hours of crawling but could mean the sacrifice of a weapon. If this seems like a too easy way out of a fracture then pain could become a factor. The character could then be in pain for an extended period of time that could only be reduced with painkillers.