Hip joint sonography in skeletal dysplasias with metaphyseal involvement. Possibilities of erroneous assessments

Skeletal dysplasias with metaphyseal involvement show radiological changes which permit their classification. There are, however, changes in the cartilage which could be demonstrated by hip sonography in two children, one with Stickler's syndrome and the other with metaphyseal chondrodysplasia. The dangers of mis-diagnosis are discussed.