Pseudoachondroplastic dysplasia in miniature poodles: clinical, radiologic, and pathologic features.

The clinical, radiologic, and pathologic features of pseudoachondroplastic dysplasia were studied in 13 affected Miniature Poodles. The disease became evident when pups were about 3 weeks old. Normal-appearing and affected pups were in the same litter, and both sexes were affected. Abnormal locomotion with abducted hindlimbs and flattened rib cages were accompanied by short, bent limbs and enlarged joints. Radiographically, areas of stippling and patchy densities were evident in the epiphyses. Histologically, these densities were identified as areas of bone associated with retarded ossification. After growth is completed, the epiphyses, ossify, but the bones are shortened and deformed. General health appears normal, except for restricted locomotion due to secondary arthritis and difficult breathing in dogs with a deformed thorax.