Ultrasound may reveal long bones that are shortened. There are several possibilities, including short-limbed dwarfism. Seen here is a radiograph demonstrating short, curved femora and humeri, along with prominent platyspondyly of the vertebrae. This is thanatophoric dysplasia. As the name implies, this is a lethal condition, but it occurs sporadically. Achondroplasia is another form of short-limbed dwarfism that is an autosomal dominant condition which is lethal in the homozygous form.

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