Kathleen wrote:

Hip dysplasia is a congenital malformation of the hip joint.

Minor correction he hip dysplasia is hereditary (that is, it's transmitted
through the genes) but not congenital (which means present at birth). Puppies
with hip dysplasia are born with normal joints, but they develop abnormally -
in fact, the very term "dysplasia" means abnormal development. The fact that
it's a developmental condition is the reason that we can't xray puppies at
8 weeks old and know for sure if they'll be dysplastic or not.

People often get the terms "hereditary" and "congenital" confused, but a
particular condition can be one or the other or both. For instance, there
are a number of congenital abnormalities (such as absence of a limb or
deafness) that can be caused by environmental exposures in the uterus -
those are congenital, but not hereditary. Hip dysplasia is an example of
the opposite phenomenon.

Hope that clarifies.

Dianne