Thank you all for your imput!
I put Skipper in the hospital pen this afternoon. That alone will help her, she can have her own food & water dishes without being bumped away by her flockmates. Plus there won't be any big pesky roosters trying to mate with her, poor dear, when they do she can't hold herself up and they squash her flat.
I found all sorts of helpful medications at the feed store, the only problem is that they come in horse-sized containers with price tags to match. I cannot justify the expense to treat a chicken, so we'll see how much we can help using more economical materials.
Tonight I soaked some cotton squares in epsom salted water, then tied it to her hock with an old sock. Tomorrow after church I will attempt to lance & drain the infection using the syringe I bought today. Then I'll put regular antibiotic ointment on it & pray fervently for her recovery.
Speckledhen, I'll look for those posts about your rooster Zane. What do you mean, he can't walk? Can he get around by hopping? If I can't help Skipper to use both legs I'll have to find someone who wants a house or caged chicken. I free range my flock every afternoon & I fear a blond hen with a pronounced limp will be awfully attractive to the hawks.
Please keep Skipper in your prayers, and me too as I try to remedy her injury. I really dislike all this icky business with bodily discharges, wish I could phone it in or do the job using 10-foot poles instead...