Fetal Skeletal System

The prevalence of skeletal dysplasias is between 1 and 2000, and 1 and 4000 live births. While here are over 200 skeletal dysplasias approximately four disorders comprise 70% of the total: Achondroplasia, thanatophoric dysplasia, osteogenesis imperfecta, and achondrogenesis. The appropriate identification of lethal skeletal dysplasia is important not only for current pregnancy management, but also for genetic counseling concerning future pregnancies. Detection of skeletal dysplasias is usually possible by prenatal ultrasound, an accurate specific diagnosis is possible by radiologic, pathologic and molecular genetic examination. A total body ultrasound approach should include assessment of the following: Limbs, long bones and extremities, bone mineralization, any joint contractures, joint dislocations, fetal calvarium, spine and thorax.