Introduction Osteogenesis imperfecta (OI), a disorder of bone characterized by hypomineralization of the skeleton, was the first disorder proposed to be due to a defect in collagen. It is characterized by life-long bone fragility and fracture predisposition. Other features, depending…
Introduction Hypophosphatasia (HPP) is an autosomal recessive disorder that is characterized by poor mineralization of bones and teeth. There are at least six phenotypes, which are distinguished from each other by age at diagnosis, inheritance pattern, and prognosis. The primary…
Introduction Fibroblast growth factor receptor 3 (FGFR3) disorders compromise of a spectrum of disorders that include thanatophoric dysplasia, achondroplasia, and hypochondroplasia, among other rare disorders such as severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN), and craniosyntoses syndromes. They…
Introduction Diastrophic dysplasia (DTD) is an autosomal, recessively inherited skeletal dysplasia characterized by short limbs, normal-sized skull, cleft palate in one-third of patients, characteristic swelling of the pinnae cartilage, contractures of the large joints with deformities, spinal abnormalities (scoliosis, exaggerated…
Introduction Chondrodysplasia punctata refers to a group of skeletal dysplasias that are characterized primarily by punctate calcifications in cartilage (calcific stippling). These disorders are characterized by short-limb dwarfism, spinal abnormalities, facial dysmorphisms, joint contractures, skin lesions, and occasionally cardiac malformations.…
Introduction Campomelic dysplasia (CD) is a skeletal dysplasia characterized by abnormal facies, multiple congenital anomalies, a typical pattern of skeletal abnormalities, and frequent male-to-female sex reversal. Newborns with CD often die as a result of respiratory insufficiency and congenital anomalies.…
Introduction Atelosteogenesis (AO) refers to a group of lethal short-limb skeletal dysplasias characterized by an abnormal, characteristic facies and hypoplastic or dysplastic tubular bones. Specific radiographic abnormalities, distinct histopathology, and differing inheritance patterns distinguish the three well-recognized types of AO.…