Hello, welcome to BYC!
So sorry about your hen, good luck with her.
I would treat her for shock, and do as @Jenbirdee said. Make sure you thoroughly check her over for injuries.
You may want to treat her with some vitamins to help with her balance and legs, to see if it'll help. Every day, give 1/2 a tablet of vitamin B Complex and one vitamin E 400IU. Give her some eggs too, to help her absorb the vitamin E more.

So sorry about your hen, good luck with her.

You may want to treat her with some vitamins to help with her balance and legs, to see if it'll help. Every day, give 1/2 a tablet of vitamin B Complex and one vitamin E 400IU. Give her some eggs too, to help her absorb the vitamin E more.