Metaphyseal and spondylometaphyseal chondrodysplasias.

Diseases characterized by defective metaphyseal ossification, (metaphyseal chondrodysplasias) and defective spinal and metaphyseal ossification (spondylometaphyseal chondrodysplasias) constitute an important group of congenital intrinsic diseases of bones in which orthopedic treatment is of utmost interest. The most common types of metaphyseal chondrodysplasias (Jansen, Schmid, McKusick, and Metaphyseal Chondrodysplasia with Pancreatic Insufficiency and Neutropenia) and spondylometaphyseal chondrodysplasias (Kozlowski) have characteristic well-defined diagnostic features. The importance of proper diagnosis for practical reasons--appropriate medical and psychological treatment, professional training and genetic counseling--cannot be overemphasized. Elucidation of the pathogenesis in this group of diseases is bound to emerge from future histochemical and biochemical research.