Hey everyone! I know its been awhile since I've posted, sorry bout that :P

Alphais, my three legged Rio Grande leopard frog, seems to have a problem.
I was out of town for a few days, she was fine before I left but now she has a lot of hard swelling in her stump. It was fat and normal size a week ago but now it's almost twice that!! Does anyone know what might have caused it? There are no external injuries whatsoever.

Thanks y'all