I have a 10 year old tabby named chunk — he is overweight hence his name. Roughly a month or two ago we noticed that he started to limp. While he isn’t holding the paw or crying while walking, it is a noticeable limp. He is still jumping up on the bed and off, walking up and down all the stairs in the house, eating, drinking, and grooming himself. We can’t touch the paw, rub on the paw, and Chunk does not react in anyway as if it hurts him. My question is, his one paw is somewhat swollen at the knuckle. Could this be arthritis? I don’t want to take him to the vet because he does not handle that well and I’m worried about giving him a heart attack or other health issue by taking him to the vet for something that might be nothing. You can see in the picture the differences in his paws. Thank you in advance!