It looks more like it could be a type of arthritis, perhaps mycoplasma synovitis, since there is swelling at the ankle and the hock joint together. \If not, then she injured both joints. She also looks to have some bruising spots on her legs. In what state do you live? Here is a good poultry vet locator, and you may also want to post in your states thread for answers:
http://www.poultrydvm.com/poultry-vets.php
http://www.poultrydvm.com/poultry-vets.php