That's a very tough choice to make. I'm leaning toward inside or PTS. Joints that have been damaged like that tend to get arthritic as years go by. I know having broken a bone or two during my days, that come damp, or cold weather, my broken areas downright ache. Is Kurby very young still? If so then he's more apt to heal better, and then could be put back out. I'd be concerned too about him re-damaging the area in the future. Ughhh...not easy to think about.