The diagnostic efficiency of screening examinations for patella luxation in dog toy breeds

A standard classification for patella luxation has been established in Swit zerland and was presented to private veterinarians in a series of continuin g education courses. The diagnostic efficiency, sensitivity and specifity h as been evaluated. The success rate of 88 % agreement between the diagnosis made by the participants and the references of the University Veterinary T eaching Hospital in Zurich is quite satisfying. Difficulties were mainly se en in the diagnosis of patella luxation grade 1 and 4. The test performed b y the participants showed that when a medial and a lateral patella luxation were present in the same stifle, quite often the lateral luxation was miss ed and only the medial luxation was diagnosed. Fortunately this has no cons equences for the breeding selection of toy breeds, because the medial patel la luxations are of higher grade.