EARLY DIAGNOSIS OF HIP-DYSPLASIA - A STRESS-RADIOGRAPHIC STUDY

Presently, the diagnosis of hip dysplasia is based on a single pelvic radiographic examination of the dog at the age of 12 to 24 months. How ever, by this method, only a static appearance of the coxofemoral join t is evaluated. The purpose of our study was to diagnose hip dysplasia in young dogs and consequently, we included a radiographic evaluation of the dynamic appearance of the coxofemoral joint. A stress-radiogra phic examination was applied to 23 German Shepherd Dogs at the age of six and 12 months to obtain maximal reduction and maximal dislocation of the coxofemoral joint. Finally, at the age of 12 months, the hips w ere examined radiographically using the conventional criteria for hip dysplasia. At the age of six months, dogs with hip dysplasia showed si gnificantly greater joint laxity and lateral dislocation of the femora l head than normal dogs. However, some predysplastic dogs, with latera l dislocation of the femoral head, developed normal hips and would be approved for breeding. Based on these findings, we conclude that stres s-radiographic examinations of young dogs provide important, hitherto unrecognized, information of relevance in the future screening program mes to reduce the incidence of hip dysplasia.