I am so sorry to hear about your chicken! She sounds like she is doing well given the circumstances. Two of our hens got attacked today...by miniature pischers (not ours!). They are pretty badly injured, but I think they will pull through as well. For small dogs, they sure did some damage.
As for the shock collars. We have three dogs (who were in our room sleeping when our drama occurred...otherwise I think our dogs would have protected the chickens). While two of our dogs adapted to the chickens well, one of our dogs (a pit mix) was a bit too curious (though not necessarily aggressive). After a short while with the shock collar, she learned to be nice to the chickens. When we are gone the chickens are locked in their run, but when we are home the chickens, dogs and cat all roam the backyard together...no problems! While I don't expect most people are able to have this much luck, I do believe the shock collar will help. The most important piece of advice I can give though is put the collar on for a few days first. That way the dog does not associate the shock with you. Also, when disciplining the dog with the shock collar, do not yell at the dog. This will also associate you and the shock together. Good luck and hope your chicken does well.
I must also add, that I do not advocate shock collars in all cases. A very aggressive dog or a very sensitive dog are probably not the types of dogs that I'd recommend shock collars for.