1. This chondrodystrophy, characterized by an abnormality in conversion of cartilage to bone, is the most common form of short-limb dwarfism; characterized by short stature with rhizomelic shortening of the limbs, large head with frontal bossing and midface hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, genu varum, trident hand, characteristic radiographic skeletal findings, and neurologic symptoms complicating hydrocephalus and spinal canal stenosis. Autosomal dominant inheritance with most cases sporadic, caused by mutation in the fibroblast growth factor receptor 3 gene (FGFR3) on chromosome 4p.
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