Spondylometaphyseal dysplasia (SEMD), Sedaghatian type is a neonatal lethal form of spondylometaphyseal dysplasia characterized by severe metaphyseal chondrodysplasia, mild rhizomelic shortness of the upper limbs, and mild platyspondyly.
An abnormality of skeletal development characterized by a disturbance of the metaphysis and its histological structure with relatively normal epiphyses and vertebrae.