Frequently, breeders want early knowledge of the hip status on puppies in a given litter. Preliminary hip evaluations may be as valuable to the owner or breeder as the final OFA evaluation. This allows early selection of dogs for use as show/performance/breeding prospects and dogs best suited for pet homes.
The OFA accepts preliminary consultation radiographs on puppies as young as 4 months of age for evaluation of hip conformation. If the dog is found to be dysplastic at an early age, the economic loss from the cost of training, handling, showing and so forth can be minimized and the emotional loss reduced. These preliminary radiographs are read by the OFA veterinary radiologists and are not sent to outside radiologists. The same hip grades are given to preliminary cases.
A recent publication* compared the reliability of the preliminary evaluation hip grade phenotype with the 2 year old evaluation in dogs and there was 100% reliability for a preliminary grade of excellent being normal at 2 years of age (excellent, good, or fair). There was 97.9% reliability for a preliminary grade of good being normal at 2 years of age, and 76.9% reliability for a preliminary grade of fair being normal at 2 years of age. Reliability of preliminary evaluations increased as age at the time of preliminary evaluation increased, regardless of whether dogs received a preliminary evaluation of normal hip conformation or HD. For normal hip conformations, the reliability was 89.6% at 3-6 months, 93.8% at 7-12 months, and 95.2% at 13-18 months. These results suggest that preliminary evaluations of hip joint status in dogs are generally reliable. However, dogs that receive a preliminary evaluation of fair or mild hip joint conformation should be reevaluated at an older age (24 months).
*Corley, EA, et al. Reliability of Early Radiographic Evaluation for Canine Hip Dysplasia Obtained from the Standard Ventrodorsal Radiographic Projection. JAVMA. Vol 211, No. 9, November 1997.