Canine Hip Dysplasia Screening Within the United States: Pennsylvania Hip Improvement Program and Orthopedic Foundation for Animals Hip/Elbow Database.

Canine hip dysplasia (CHD) is a complex, polygenic disease radiographically associated with hip subluxation and development of osteoarthritis. Screening programs have been established with the goal of hip improvement, with the most common in the United States being OFA hip scoring and the PennHIP method. When evaluating the single hip-extended view used by OFA versus the 3 radiographic views and associated distraction index (DI) used by PennHIP for CHD screening, the scientific evidence supports the use of the DI and PennHIP method. OFA scoring can be used to effect hip improvement, especially when incorporated into estimated breeding values.