Achondroplasia
Of the estimated 200 types of dwarfism, achondroplasia is by far the most common, accounting for approximately half of all cases of profound short stature. Achondroplastic dwarfism is characterized by an average-size trunk, short arms and legs, and a slightly enlarged head and prominent forehead. Most achondroplastic dwarfs are born to average-size parents, and account for somewhere between one in 26,000 and one in 40,000 births. Adults, on average, are four feet tall. Young children, especially, should be examined for such potential problems as central apnea, obstructive apnea, and hydrocephalus.

Q: What is the definition of dwarfism?

A: Little People of America (LPA) defines dwarfism as a medical or genetic condition that usually results in an adult height of 4'10" or shorter, among both men and women, although in some cases a person with a dwarfing condition may be slightly taller than that.

Q: What are the most common types of dwarfism?

A: By far the most frequently diagnosed cause of short stature is achondroplasia, a genetic condition that results in disproportionately short arms and legs. (The term "disproportionate" is meant only as a point of comparison with people who do not have achondroplasia or any other type of skeletal dysplasia. The arms and legs of a person with achondroplasia are perfectly appropriate for someone with that genetic condition.) The average height of adults with achondroplasia is 4'0". Other genetic conditions that result in short stature include spondyloepiphyseal dysplasia congenita (SED), diastrophic dysplasia, pseudoachondroplasia, hypochondroplasia, and osteogenesis imperfecta (OI). As one might expect from their names, pseudoachondroplasia and hypochondroplasia are conditions that are frequently confused with achondroplasia; diastropic dysplasia occasionally is, too. OI is characterized by fragile bones that fracture easily.

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Powerpoint Presentation on Dwarfism

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