Chick with Eye injury

[old biddy]

My chick has progressed well in that both eyes are now open and functional, it is eating and drinking on its own, and it is no longer constipated (molasses and water helped with that. However, it still cannot keep its balance. It falls forward and backward rather than off to the side. It doesn't seem to have splayed legs, though one leg appears to be more "stiff legged" than the other. Is this a symptom of some disease or illness? If not then it must be an injury that hasn't healed yet. Any ideas anyone?