Many dogs have what I call a "kicking spot" (when you scratch it, they kick their leg) When I was a kid, our dog had a few, the dog I have now has 2 or 3, the dog I used to have had two, and if we scratched his belly at both sides, sometimes he wouldn't even be able to stand up! He'd try to kick both legs at once! This was very funny, and it didn't hurt him at all. In fact he was built like a mini-tank, with a strong back and strong legs.
Has yours always done this? That's the question. If she's done this all of her life, it may just be she has a big "kicking spot" -and nothing at all to worry about...
But if this is a recent development, then it needs checking out, I think. Any changes are always best to get checked out with a vet, just in case something might be wrong with her back.
She's just started doing this in the past few weeks.
Right...then it sounds like there is definitely some sudden sensitivity in her back. I would get this checked out in case it could be a prolapsed disk.
It may not be...but best to get her checked.