Without seeing her its kind of hard to undertstand exactly what you mean but I'm assuming that some areas of her coat just aren't growing back at all. Sometimes when you clip or shave a dog, their coat won't grow back if they have a thyroid problem. Most people don't know that there is anything wrong with their dogs' thyroid and when they shave them, their coat doesn't grow back.

I've heard of post-clipping alopecia before, but really don't know anything about it or if its the same as what I described above.