Hip Dysplasia is a common*, heritable disease in cavalier King Charles spaniels which can cause the dogs terrible pain and debilitation. Hip Dysplasia (HD) is a common*, heritable disease in Cavalier King Charles Spaniels which can cause the dogs terrible pain and debilitation. HD is the abnormal development of the hip, which can produce various degrees of arthritis (which also may be called degenerative joint disease, arthrosis, or osteoarthrosis). Early symptoms of hip dysplasia include bunny hopping or swiveling the hips when running, having a difficult time rising from a down position or when climbing stairs. It is not predictable as to when or even if a dog with HD will start showing signs of lameness due to pain. There are many environmental factors, including caloric intake and the level of exercise, which can affect the severity of pain and lameness. Many dysplastic dogs with severe HD can run, jump, and play as if nothing is wrong, and other dogs with barely any HD x-ray indications are severely lame.