Spondyloepimetaphyseal Dysplasia Research Articles

Pathogenic mechanisms in osteochondrodysplasias.

We performed histochemical, immunohistochemical, electron-microscopic, and microchemical studies on cartilage growth plates from sixty-eight patients with nineteen different forms of human osteochondrodysplasia. Cartilage biopsies were obtained during orthopaedic procedures. Postmortem specimens were obtained within a short time after death. The combined morphological and biochemical studies revealed specific abnormalities suggestive of a particular biochemical defect in several chondrodysplasias. In pseudoachondroplasia, non-collagenous protein accumulated in the rough endoplasmic reticulum of chondrocytes and a proteoglycan species that normally is present in the extracellular matrix was not detected by gel electrophoresis. The accumulated material was stained with antibodies against the core protein of proteoglycan. This strongly suggested that in this syndrome an abnormal core protein of a proteoglycan species is not properly transferred to the Golgi system. In Kniest syndrome, intracytoplasmic accumulation of metachromatic material, dilatation of rough endoplasmic reticulum, and an abnormal gel-electrophoretic pattern of cartilage proteoglycans suggested an abnormality of cartilage proteoglycan metabolism. Abnormalities that probably are related to degradative lysosomal processes of proteoglycans in chondrocytes were found in spondylometaphyseal dysplasia of the Kozlowski type. An abnormal organization of type-II collagen was found in fibrochondrogenesis. In diastrophic dysplasia, an abnormal organization of collagen was found in areas of interterritorial matrix and around many degenerated cells, but also in the lacunae of cells without ultrastructural signs of degeneration. The segment-long-spacing form of collagen prepared from cartilage of three patients with diastrophic dysplasia showed an abnormal cross-striation pattern in a portion between bands 42 and 45, corresponding to the position of the alpha 1(II) cyanogen-bromide-derived 10,5 peptide. This suggested that in this syndrome there is a structural alteration of the type-II collagen molecule. There was an accumulation of intracellular lipid in pyknodysostosis and in hypochondrogenesis, and of glycoproteins in several atypical cases of spondyloepiphyseal dysplasia. In a pair of twins with an atypical form of spondyloepiphyseal dysplasia, the presence of many multinucleated chondrocytes suggested a primary impairment of cell division. A knowledge of the pathogenic mechanisms in osteochondrodysplasias might improve the classification; aid in diagnosis, prognosis, and genetic counseling; and contribute to the understanding of normal endochondral growth.(ABSTRACT TRUNCATED AT 400 WORDS)

A new variant of spondylometaphyseal dysplasia with autosomal dominant mode of inheritance.

Clinical and radiographic evaluation of an infant boy and his father revealed findings suggesting a new variant of spondylometaphyseal dysplasia with an apparently autosomal dominant mode of inheritance. The main...

Spondylo-Metaphyseal Dysplasia

One sporadic case of the common type of spondylo-metaphyseal dysplasia and three cases of "new varieties" are reported. In the author's opinion spondylo-metaphyseal dysplasias are much more common than generally recognised. Brachyolmie represents spondylo-metaphyseal dysplasia with mild-minimal metaphyseal changes.

Spondylometaphyseal dysplasia

A family is described in which the father, son, and daughter have spondylometaphyseal dysplasia, consistent with an autosomal dominant pattern of inheritance. Radiologic changes spanning a period from 4 months to 31 years are described. Platyspondyly and metaphyseal deformity predominate. The severity of the radiologic changes is variable.

The Dyggve-Melchio-Clausen syndrome

Two families with Dyggve-Melchior-Clausen syndrome are reported. In the first family, Jews from Morocco, six of 10 siblings are affected. In the second family, a consanguineous marriage of Arabs from Gaza, two of three children are affected. A description of the skeletal changes in patients ranging in age from 4 to 25 years is presented. The radiologic signs of generalized platyspondyly with double humped end plates and the lace-like appearance of thickened iliac crests are pathognomonic and distinctive of the syndrome. The diagnostic features of the disease are compared to those of Morguio's disease, spondyloepiphyseal dysplasia tarda, and spondylometaphyseal dysplasia.

Spondylometaphyseal dysplasia: a variant form.

Spondylometaphyseal dysplasia (SMD), a heterogeneous group of chondro-osseous dysplasias with combined vertebral and metaphyseal abnormalities, is being recognized and reported more frequently. The cumulative experience with these patients suggests that the Kozlowski type of SMD is a distinct form, and transmitted as an autosomal dominant. Many other forms of SMD exist which, as yet, cannot be completely classified. A father and daughter who demonstrate a variant form of SMD, both with absence of the odontoid processes, are described and their place in the spectrum of this group of diseases is discussed.

Spondylometaphyseal dysplasia (Kozlowski). Report of affected mother and son.

Spondylometaphyseal dysplasia (Kozlowski), a specific entity within the complex group of spondyloepiphyseal-metaphyseal dysplasias, has been mentioned several times in the European literature but is less familiar to English-speaking doctors. It is inherited as an autosomal dominant and becomes manifest in early childhood with shortening of the spine and lower limbs. The major roentgenographic features are generalized platyspondyly, short femoral necks, and irregularity of the acetabula and metaphyses throughout the long bones, predominantly in the lower extremities.