Im sorry but she isn't fat. Remember Im only saying this is what I did over a simular situation. She has some sort of inflammation. Can you try anti-Inflammatory's I know the ones the vet can get you come with a big price last year I asked for help and it was suggested I use naproxen "alive" (I was desperate) but didnt know how much to give. What I did is crush a 220MG tablet added 6cc's of water then used 6 1cc syringes to suck it back up. gave me 6 doses 1 every 12 hours. She also got long soakes in the bathtub. Just a thought.