Can you put her in a smaller cage or pen where she can't move around much? Sometimes they sprain something; and there is not necessarily any heat or swelling in the foot or leg. We have had them do that before and keeping them confined where their movements are fairly limited; (they can't run, or jump off a perch or spend a lot of time walking around) has helped, and eventually they have been able to walk normally again. But it takes a while, we had one that took six weeks bf she healed. Feel around the hens hips to see if they feel normal and equal to each other; they will limp and or not put weight on a leg with a dislocated hip, and the rooster can dislocate the hen's hip if he is too rough.