The first sign to look for if your dog is developing arthritis is a limp or an irregular walk. Your dog will be avoiding the aching joint and attempting to move it as little as possible. Cold or rainy weather, as well as early mornings or periods after not using the joint for extended periods of time, such as a nap, will often worsen your dog’s limp.
Throughout arthritis’s progress, he will become less mobile and enjoy his routine less and less. Activities such as leaping on the couch, playing fetch, climbing in your lap, or longer walks may become too painful for him. Often times on the leg with arthritis the muscles will deteriorate from lack of use and appear much smaller than the adjacent leg.
Also, dogs have been known to nip at the sore area to sooth the pain, and many owners will mistake this as a skin problem.