Maybe the itching is related to her heat cycle.
Johnny's itching and scab-like spots on the upper areas of his front legs stopped when I took him to the vet and got meds. I'm not too hopeful that this will go away after the meds stop as I've read dog allergies don't get better as the dog grows. He's on the doggie version of prednisone, not itching/biting, and the ugly scabs went away too.
He also had a bit of an infection from the itching/biting so get that checked out.
I also asked the vet about possibility of food allergy and he said that determining that becomes a major undertaking.
Good luck with solving the problem.