Cause is not yet known but disease has been linked to excesses of protein and Vitamin D or calcium, to a deficiency of Vitamin A, or to liver problems. Consult your avian veterinarian. Good hygiene practices will keep mites in check. Cage should be thoroughly cleaned, and all wooden toys, and perches discarded to prevent re-infestation. Consult your avian veterinarian for treatment.
Infection usually results from a previous injury or by using sandpaper perches.
Poor nutrition and poor sanitation can contribute. This is transmissible to other birds if they come in contact with infected bird's discharge. If left untreated, it can be very serious resulting in loss of toes, foot or even life as disease progresses. Llameness, obvious inflammation of the joints, and loss of function of joint. Make food cups and perches easy to reach.