Senior Dog Muscle Wasting. Signs of muscle atrophy include weight loss and weakness. The medical term for loss of muscle mass in dogs legs is muscle atrophy, which depicts the gradual wasting seen in a dog's muscles.
Read on for signs to help you determine whether or not your dog is suffering, and if so, what to do about it. Muscle atrophy is when the muscle basically wastes away and reduces in size and strength. An aging dog can experience atrophy of muscles.