The Orthopedic Foundation for Animals rates hip dysplasia in seven categories with ratings of excellent, good and fair being considered normal. The British Veterinary Association uses a numeric scale of 0 to 53 with 18 or less being considered normal. German shepherds average a 13 on the BVA scale.
The OFA and BVA assign their grades based on a number of criteria, including how well the hip socket is formed, how well the femoral head is seated in the socket, and whether or not irregularities are found in the joint. For breeding purposes, a German shepherd should have a normal hip, have at least 75 percent siblings with normal hips and come from bloodlines that consistently have normal hips.