3 week old Buff with leg issues

[bailsbfly]

I have 6 chickens that are about 3 weeks old. I don't know what happened, but I came home from work a few days ago and she was limping. She holds one leg kind of in front of her, and the toes on the other leg look kind of like they're broken. On the side with the leg she holds in front of her, she has a bony bump sticking up about 2 cm on her back where her hip is, but it doesn't feel like her leg is out of joint. She eats and drinks normally but I have no clue what to do about her legs. Help would be much appreciated.
Here is a link to the video of the injured Buff Orpington:

Thanks!