Take her to the vet, because they will do X-rays to see if there is any
joint damage, and how extensive it is. Then they will prescribe anti-inflammatories which will help, and reduce any pain she has, and you never know...very soon, she may be running around again with the young 'uns!
Another thing that won't do any harm is to start her on Glucosamine and Chondroitin supplements. This really works, and is completely natural.