Hip Dysplasia is an abnormal formation of the hip socket that, in its more severe form, can eventually cause crippling lameness and painful arthritis of the joints. It is a genetic (polygenic) trait that is affected by environmental factors.
The test for the hip screening is called "OFA Hips" and is done when the dog is (minimum) 2yrs old, although preliminary but not official screenings may be done prior. An x-ray is taken at the vet office and sent to the OFA (Orthopedic Foundation for Animals) where it is graded by multiple veterinary specialists to be excellent, good, fair, borderline, mild, moderate, or severe. (Only excellent, good, and fair are considered to be within the normal limits and given an OFA number within the OFA database).