Achondroplasia

**Definition:** An autosomal dominant disorder that is the most frequent form of short-limb dwarfism. Affected individuals exhibit short stature caused by rhizomelic shortening of the limbs, characteristic facies with frontal bossing and mid-face hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, GENU VARUM, and trident hand. (Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/Omim, MIM#100800, April 20, 2001)

**Tree numbers:** - C05.116.099.343.110 - C05.116.099.708.017 - C16.320.240.500