I have a young whistler who has his back legs outstretched. He was fine this morning but this evening when I had a peek at the frogs he was lying on the bottom of the terrarium with his backlegs stretched out. I've made sure he was well hydrated and popped him in a small container to feed (although his belly was quite full) he has been interested in the fruit flies but hasn't had more than one or two, he is now moving well, even climbing up walls with just his front legs.
I haven't seen this before except in a frog i kept as a child - after it jumped into hot soap dishwater (it survived). What causes it and what can I do? Other than the back legs he seems quite normal.