Common signs of arthritis are:

• Favoring a limb/limping.
• Difficulty sitting or standing. Taking more time to get moving in the morning.
• Sleeping more, decreased activity and less interest in play. Reluctance to walk, climb stairs, jump, or run. Less excited to greet you when you come home.
• Weight gain.
• Attitude or behavior changes. Being less alert.
• Yelping in pain when touched. Hot or swollen joints.

Symptoms can wax and wane, so that one day a dog may play less than usual, the next day he or she will be running around like a puppy. The degree of stiffness varies with temperature, and often worsens when the weather is colder. During walks or runs, some dogs fall behind or tire more easily, while others warm into the exercise and then become sore afterwards when cooling down. Dogs may lick at very painful joints. If the limb is not being used, the muscle may start to waste away. Dogs in a lot of pain may also lose interest in food.