RELIABILITY OF EARLY RADIOGRAPHIC EVALUATIONS FOR CANINE HIP-DYSPLASIA OBTAINED FROM THE STANDARD VENTRODORSAL RADIOGRAPHIC PROJECTION

Objective-To determine reliability of preliminary evaluations for cani ne hip dysplasia (CHD) performed by the Orthopedic Foundation for Anim als on dogs between 3 and 18 months of age. Design-Retrospective analy sis of data from the Orthopedic Foundation for Animals database. Anima ls-2,332 Golden Retrievers, Labrador Retrievers. German Shepherd Dogs, and Rottweilers for which preliminary evaluation had been performed b etween 3 and 18 months of age and for which results of a definitive ev aluation performed after 24 months of age were available. Procedure-Ea ch radiograph was evaluated, and hip joint status was graded as excell ent, good, fair, or borderline phenotype or mild, moderate, or severe dysplasia. Preliminary evaluations were performed by 1 radiologist; de finitive evaluations were the consensus of 3 radiologists. Reliability of preliminary evaluations was calculated as the percentage of defini tive evaluations (normal vs dysplastic) that were unchanged from preli minary evaluations. Results-Reliability of a preliminary evaluation of normal hip joint phenotype decreased significantly as the preliminary evaluation changed from excellent (100%) to good (97.9%) to fair (76. 9%) phenotype. Reliability of a preliminary evaluation of CHD increase d significantly as the preliminary evaluation changed from mild (84.4% ) to moderate (97.4%) CHD. Reliability of preliminary evaluations incr eased significantly as age at the time of preliminary evaluation incre ased, regardless of whether dogs received a preliminary evaluation of normal phenotype or CHD. Clinical implications-Results suggest that pr eliminary evaluations of hip joint status in dogs are generally reliab le. However, dogs that receive a preliminary evaluation of fair phenot ype or mild CHD should be reevaluated after 24 months of age.