Asymmetric and symmetric long bone bowing in two sibs: an apparently new bone dysplasia.

We describe 2 sibs, one with congenital asymmetric long bone bowing and one with congenital symmetric long bone bowing. Other bony abnormalities in these sibs include beaten metal appearance of the skull, dolichomacrocephaly, ocular hypertelorism, and anterior beaking and bone-within-bone appearance of vertebrae. A differential diagnosis including campomelic dysplasia, kyphomelic dysplasia, hypophosphatasia, Grant syndrome, and osteogenesis imperfecta, and a discussion of potential mechanisms of long bone bowing are presented. The condition that these sibs have shares some characteristics of the above bone disorders, but appears to be a separate entity which to our knowledge has not been described previously.