Hello,
Rest and time is the best medicine at this point, the swim may help as well. As she is weightless in water it will give her a opportunity to get some movement and exercise the leg. (Just watch her closely if she appears tired, go ahead and limit her).
For now you can use warm compresses to help alleviate the stiffness. Towels placed in the dyer to warm up can be laid over the leg or on her bedding to allow it to keep it from stiffing up.
This will take some time to heal fully, but continue with the nightly walks to help keep it moving as well.
Walter
Breeder
Breeder and pet health consultant. Have spent a number of years with dog rescue, training and health