One of mine was on restricted movement early this year and it's not easy! I used a cage that was about twice the size of a cat carrier, and she was still pretty hyper. The only thing that seemed to calm her down was swapping out her wood and hay every 5 hours, so maybe you could give that a shot. You could also try leaving the TV or radio on in the room she's in. I always have something on for my guys.
Also, be sure to tell her she's a good girl a lot so that she doesn't feel like she's being punished. Since she already has a sprain, a depressed chin in an itty bitty space would be heartbreaking, so try to keep her as happy as you can.
Before you move her back into her normal cage, ask your vet whether or not you should remove the shelves and the wheel for a little longer to make sure she doesn't injure herself more.
Good luck!