Thanks for the additional information. It is helpful. I am so sorry this little girl was subjected to such abuse at such a young age. It is a shame. I do worry that it might have led to some long term pain issues from the pins and repairs done. Often dogs will develop arthritis and aches from severe injuries that remain long after the bones have healed. This might be a contributing factor to he seemingly jekyll and hyde act. She may allow some petting but if she is in pain, it becomes too much and she lashes out to stop you from petting her. There are some medical conditions that can cause sudden aggression as well as pain and those may be a factor. Unfortunately, these would not be able to be ruled out without testing.
Another part of this is a dominance issue. She is indeed trying to boss the humans around and it seems to be working. As long as she is ok with what you are doing, everything is fine, but then she become tired of being touched and just wants to lay there undisturbed and when you continue, she lashes out. Over time, YOU learn that when she growls, you stop petting or leave her alone. This is behavior we see with dominant dogs.
Many dominant dogs are described as well behaved until you try to get them to do something they do not want to do, and then they reprimand you either with a growl or bite if you don't heed the growl. Things like taking away something they want, making them move when they don't want to, waking them up, etc can cause them to reprimand (bite) you. Seems that this should be familiar to you.
Dogs that are allowed on furniture (even if put on the furniture) tend to feel that since they are elevated to your level or higher if on your lap, they mentally feel elevated as well in the pack order and thus are the boss. Keeping them on the floor can help lower them mentally back to a submissive position in the pack. So the first thing is to not allow her higher that the humans or even on the same level. If she insists on getting up on the furniture or lap, attach a leash and use it to remove her from the furniture. Give a correction in the form of a short tug and firm "NO" when ahe attempts to get on and a treat when she starts not trying to get on the furniture. Thus you are providing negative reinforcement for the getting on the furniture and positive reinforcement for the desired behavior (not attempting to get on the furniture). The leash stops her from biting you when attempting to move her.
There are other ways to regain the dominant position in the house as well. The best way is to start obedience training. While a formal training class is great, you need to do a lot of work at home with her. Practice what you learn in class at home.
Training works best if you train at least 30 minutes a day (two 15 minute sessions). I would start making your dog work via the Nothing in life is free program (NILF). It is outlined below.
Obedience training helps by making the humans the bosses and lower members do not reprimand the boss, and it also helps a dog gain self confidence by teaching them what humans expect of them when they give a command, so it helps with fear biting as well. It really is an all around great behavior modifier for various situation.
You want to keep a short leash on her to get her attention when she needs a reprimand. If she disobeys in any way including growling at you or your husband, use the leash and a verbal reprimand. I know not letter her on the furniture may be difficult for you, but you have to at least for a few weeks after she stops trying. After that, make her obey a command in order to EARN the privilege of coming on the couch for some affection. Once YOU decide it has been long enough, give the command for her to get off the couch. Some use OFF, other use GO. She respect you more and be less likely to try to reprimand you since the obedience work and lowering her in the pack will make you the boss and you don't reprimand the boss. Only the boss reprimands. Now it won't help for pain related attacks.
So you have already started on the most important part of correcting the situation with the obedience training. So just add the daily practice, and keep her off the furniture and make her work for the basics in life. It is not cruel. Additonally, if you are giving her attention by petting her when she is displaying unwanted behavior, you are actually encouraging the behavior. I know it is hard to be firm with a dog when you know they have had a horrible start in life, but they tend to put that behind them quicker than humans do.
In addition, if the situation is not improving using the techniques I describe, you may have to consult a professional behaviorist. You can usually find a behaviorist by asking your Vet for a recommendation or you may be able to find one using the following site.
I hope this information is helpful to you and you are satisfied with my response. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have .