Bone Health

GENERAL PRINCIPLES OF SPINAL DEFORMITIES IN THE SKELETAL DYSPLASIAS What is skeletal dysplasia? The term skeletal dysplasia refers to a "bad formation" of the bones and joints. All the bones of the skeleton are affected: this differs from a skeletal dysostosis, in which a group of bones are affected while the remainder of the skeleton is normal. Patients with skeletal dysplasia are usually, though not always, of small stature. The small stature is disproportionate: the different parts of the skeleton are affected to differing degrees. For example, the trunk may be smaller than the limbs, and within the limbs, the bones of the forearm may be more deformed than the bones of the hands, which may be relatively spared. Skeletal dysplasia is a general term that includes many distinct syndromes. The most common non-lethal form is achondroplasia, while the most common potentially lethal form is osteogenesis imperfecta. These and the other principal types that characteristically affect the spine will be discussed below.

Synonyms and related keywords: skeletal dysplasia, disproportional short stature, short stature, dwarfism, osteochondrodysplasias, thanatophoric dysplasia, achondroplasia, osteogenesis imperfecta, achondrogenesis, chondrodysplasia punctata, homozygous achondroplasia, chondrodysplasia punctata, camptomelic dysplasia, congenital lethal hypophosphatasia, perinatal lethal type of osteogenesis imperfecta, short-rib polydactyly syndromes, hypochondroplasia, rhizomelic type of chondrodysplasia punctata, Jansen-type metaphyseal dysplasia, spondyloepiphyseal dysplasia congenita, atelosteogenesis, diastrophic dysplasia, congenital short femur, Langer-type mesomelic dysplasia, Nievergelt-type mesomelic dysplasia, Robinow syndrome, Reinhardt syndrome, acrodysostosis, peripheral dysostosis, Kniest dysplasia, fibrochondrogenesis, Roberts syndrome, acromesomelic dysplasia, micromelia, Morquio syndrome, Kniest syndrome, metatrophic dysplasia, spondyloepimetaphyseal dysplasia
Author: Harold Chen, MD, MS, FAAP, FACMG, Chief, Professor, Department of Pediatrics, Section of Perinatal Genetics, Louisiana State University Medical Center
Dwarfism is a commonly used term for disproportionately short stature, although a more medically appropriate term for this disorder is skeletal dysplasia. Short stature is defined as height that is 3 or more standard deviations below the mean height for age. If short stature is proportional, the condition may be due to endocrine or metabolic disorders or chromosomal or nonskeletal dysplasia genetic defects. In general, patients with disproportionately short stature have skeletal dysplasia (osteochondrodysplasia). Skeletal dysplasias are a heterogeneous group of more than 200 disorders characterized by abnormalities of cartilage and bone growth resulting in abnormal shape and size of the skeleton and disproportion of the long bones, spine, and head.

The term ‘sphondylos’ means vertebra (Greek) and ‘epiphysis’ refers to the end of long bones that is adjacent to joints. SED principally affects the spine and the ends of long bones.

Spondyloepiphyseal Dysplasia
Last Updated: September 12, 2003
Synonyms and related keywords: spondyloepiphyseal dysplasia congenita, SED congenita, SEDC, Spranger-Wiedemann, spondyloepiphyseal dysplasia tarda, SED tarda, SED tardive, X-linked SED, spondyloepiphyseal dysplasia late, SEDL, SED Maroteaux type, SED tarda Toledo, SED with brachydactyly, SED tarda Namaqualand type, NSED, pseudo-Morquio disease, pseudoachondroplasia SED, short stature, dwarfism, skeletal dysplasia, myopia, near-sighted, retinal detachment, detached retina, deafness, deaf, scoliosis, kyphosis, lordosis
Contents: Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography Authors Parikh, Crawford & Batra

Streeter dysplasia is a term used to describe a complex disorder characterized by constricting rings, acrosyndactyly, or, often, amputations of the extremities of neonates. It is analogous to constriction band or amniotic band syndrome (ABS), which was recognized as early as 300 BC. Hippocrates suggested that extrinsic pressures from a ruptured amniotic membrane lead to the formation of bands or digital amputations. In 1652, J.B. van Helmont reported on intrauterine amputations, which he attributed to the pregnant mothers having looked upon maimed soldiers. Montgomery in 1832 and Simpson in 1836 subsequently described series of amniotic band–associated deformities and discussed the differences between agenesis- and amniotic band–induced amputations.
Synonyms and related keywords: congenital constriction band syndrome, amniotic band syndrome, ABS, constricting rings, acrosyndactyly, intrauterine amputation, digital amputations, ADAM complex, limb body wall syndrome, pseudo-ainhum, pseudoainhum, hemihypertrophy, anterolateral bowing, pseudarthrosis, leg-length discrepancy, teratologic clubfeet
Twee Do, MD 2006

Extensive illustrated discussion of dwarfism and dysplasias. Conditions described include Thanatophoric dwarfism Achondroplasia Chondrodysplasia punctata Diastrophic dwarfism Dyschondrosteoses Asphyxiating thoracic dystrophy Pyknodysostosis Chondrodysplasia punctata Osteogenesis imperfecta Neurofibromatosis Mucopolysaccharide disorders Ollier disease Multiple hereditary exostoses Proximal focal femoral deficiency Cleidocranial dysostosis Osteopetrosis Osteopoikilosis Osteopathia striata Melorheostosis Camurati-Englemann disease

Multiple Epiphyseal Dysplasia, The Alfred I. duPont Institute

Skeletal Dysplasias

spondyloepiphyseal dysplasia