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.

Diminished length of one or more metacarpal bones in relation to the others of the same hand or to the contralateral metacarpal.