Is she still able to walk? Does she move her toes or legs at all when you touch or handle them? Do they seem flaccid and paralysed or spastic? I would also put on a disposable glove and lubricate it, and insert one finger into her vent to feel for some sort of blockage inside. That might include lash egg material, a tumor, or a stuck egg, that might be causing temporary lameness. After rereading your first post, it could be stuck lash material (from salpingitis) inside pressing on her sciatic nerves. Of course, hard to know for sure while she is alive. I really think a necropsy if you lose her would be very good to find out what was effecting her.