Her bones are showing? I think you're battling something way bigger than most of us can help with over a forum. If bones are showing you're talking much more than a minor injury that can be fixed with some topical ointment and time.
With bones showing you really are going to be having a bird in major pain and have huge risk of infection. Its not really common for chickens to just eat themselves because they like the taste.
I hate to be blunt but do you have a vet involved? Reason I ask is pain medication and anti biotics are likely going to be needed to help this bird survive and the issue of bones showing will have to be addressed. There is a lot of pain and suffering that will happen with a wound of this degree and I know a lot of people can't pay the expensive vet costs so sometimes the best option is to humanely put them down.
hoping for the best!
