These things are mysteries until there is a necropsy in many cases.JGs normally have no predisposition to this, but I can find nor feel any injury on her. I wonder about genetics though because she is a hatchery girl and thus her heritage is unknown. But, seeing as my 14 other chooks are good, including my 2 other JGs, I really don't know if it was injury induced or if she herself may have a natural vitamin deficieny due to genetics. Yet another mystery, neurological or physical.
It is good that she is getting better