[Evidence of heterogeneity in dyssegmental dysplasia]

The dyssegmental dysplasia is a lethal form of neonatal short-limbed dwarfism in which unusual facies, short neck, narrow thorax, cleft palate, and reduced joint mobility are the characteristic commonly seen. Radiologically, vertebral segmentation defects and short, thick, bowed long bones are the prominent features. To date, 30 cases have been reported. Clinical, radiographic, and histologic examination of these cases of the literature demonstrates the presence of two distinct forms of dyssegmental dysplasia, the milder form (type Rolland-Desbuquois), characterized clinically by frequent survival beyond the newborn period and by distinct radiographic changes resembling Kniest dysplasia, and the severe form (type Silverman-Handmaker), characterized by stillbirth or death within the first few days of life and by distinct and more severe radiographic changes. In both types, reports of affected sibs suggest autosomal recessive inheritance.