If that doesn't help, how about calling a hatchery? I don't know what country you are in, but McMurray's in the US is a most helpful place. McMurray Hatchery
We have approximately 30 hens and a few roosters. The most important thing you can do is to isolate your hen from the others until you know what is wrong. Also be sure to wash you hands after handling her (no brainer there!).
If you have brought her inside and standing is still a chore, I'd suggest putting a small pillow or wrapped up blanket inside, something she can lean on to remain in an upright position.