Prenatal sonographic evaluation of short-limbed dwarfism: an algorithmic approach.

Prenatal sonographic evaluation of short-limbed dwarfism is initiated when a significantly shortened femur is found or by referral of a patient with a family history of skeletal dysplasia. If a short femur is demonstrated, all the long bones are measured and evaluated for bowing, fractures, and mineralization. The bone dysplasia is categorized according to whether it is mesomelic, rhizomelic, or micromelic and whether bowing or fractures are present. The fetal spine, head, thorax, hands, and feet are carefully evaluated to differentiate the type of bone dysplasia and to determine whether it is lethal. Serial examinations may be necessary. This approach will provide sufficient information to counsel the family, manage the pregnancy, and direct the postnatal evaluation.