
Hi,
Dogs can only be hip-scored (in the UK) after the age of 12 months, so any new pup won't be scored. But the parents should have been, most particularly in breeds with a higher-than-normal incidence of hip dysplasia.
Hip dysplasia (HD) is a condition where the ball of the femur doesn't fit tightly into the socket of the pelvis, due to one or more of many factors, not all hereditary. With the condition, the socket will be shallow, the femoral head will be distorted and the joint will be slack. The scoring system measures various parts of the joint depending on its shape and structure, the lower the score, the better. Each breed has a breed average which depends not only on the condition of the hips of the dogs, but also on the numbers scored.
The best hip score will be 0:0 (both sides perfect) - the worst will be 53:53 (both sides virtually dislocated).
Of course the formation of the hip joint can be affected not only by heredity, but also by congenital deformity or accidental trauma - in the womb or later, due to the wrong feeding, exercise, etc.
Even animals with excellent hips can produce offspring with HD, but the incidence is likely to be lessened.
Hope this helps a bit.
:)
PS - forgot to say - it's all about the skeleton, not the muscles!