Our 7 year old has developed this on one of his pads. This happened very quickly, like overnight. On the bottom of his foot, it’s like the pad has separated and pushed out about an inch from the pad. I have never seen anything like it and don’t even know how to explain it. We took him to the vet and he wasn’t sure either. He was going to do more research. Meanwhile they put him on antibiotics for a week to help with any infection. It’s not overly painful, he’s still walking normally. Any help would be appreciated, I don’t even know where to start researching. He’s an indoor dog, but goes on daily walks so I don’t think it was an outdoor injury.