I would keep an eye on her today to see if she is up walking around on it. If by this evening, she is limping badly or sitting a lot, you may want to cage her inside the chicken coop with the others with her own food and water. A dog crate is good. After a day or two, check to see if she can walk normally, and if not, keep her up for a week or two. Jumping up and down on roosts won't help it heal.
I would wait until it was dark and she goes to roost to try and catch her if you can, because that way she won't run all over the place like a crazy lady and hurt her leg more, know what I mean? But yes jumping down from the roost won't do her any favors, poor baby. Maybe she just "sprained" it. I have come to the conclusion that I just need a permanent special needs enclosure because it's always something with these chickens lol
That works too! I always wait until mine are on the roost to try and do ANYTHING to them. I think it is a lot easier on you and them. Although sometimes I lack the patience for that. Fortunately, I had plenty of chicken catchin' practice as a kid, UNfortunately, I lack my youthful reflexes LOL