Elbow calluses are common in dogs and large breeds seem to be more susceptible to this problem. They are thought to be the result of pressure when the dog lies on a hard surface. Mild calluses are usually not harmful. If the callus is large or becomes infected, veterinary treatment is usually necessary. The best prevention is providing soft bedding or padding for the dog's resting place, provided the dog is not inclined to chew and swallow bedding material. Choose material that can be replaced or washed frequently for sanitary purposes.