Hip replacement is getting very common.

I assume your mum is older. They'll do a bone density test. If she has a lot of bone loss (long term calcuim trouble) it can bugger up the new hip thing.

If she is fairly old I recommend formal rehab in a rehab center. Have her stay for four weeks or so. The longer the better if you can find a good one. They'll put the hert on her to get her moving but it's worth it.

If she's in a lot of pain now she'll do well and in a few months she'll be glad she did it.