Kniest dysplasia was initially felt to be a variant of another type of skeletal dysplasia called metatropic dysplasia. Kniest dysplasia is usually diagnosed at birth. The joints are enlarged at birth. Motor milestones are often delayed secondary to joint deformities. Progressive and painful joint enlargement can be accompanied by flexion contractures.
Cartilage obtained by biopsy feels soft.
Kniest-Like Dysplasia, Lethal from OMIM Sconyers et al. Platyspondyly, short limbs, and cleft palate were evident at birth. Other malformations included myopia, hypoplasia of abdominal musculature, abdominal and inguinal hernias, and mental retardation. In both forms the trunk is short with prominent abdomen and hydropic appearance. Micromelia is striking.