• Dwarfism: an intellectual disability, Abnormally short stature. Some
forms are hereditary. The Little People of America (LPA) define
dwarfism as an adult height of 148 cm (4 feet 10 inches) or less. Also
known as nanism. Dwarfism is now more correctly called short stature.
What Causes Dwarfism?
•It is a genetic disorder, usually from inheritance
•a random genetic mutation in either the father's
sperm or the mother's egg
•most common type, accounting for 70% of all cases
of short stature, is called achondroplasia.
•Dwarfism has other causes, including metabolic or
hormonal disorders in infancy or childhood
•There is more then 200 causes of dwarfism
•Dwarfism is a very rare disease
•Therefore it affects less then 200,000 people
•Gene frequency is estimated to be 1/16,000 and 1/35,000 (ref).
There are about 5,000 achondroplasts in the U.S.A. and 65,000 on
Earth (Warkany, 1971).
The prevalence rate for achondroplasia is between 0.5 and 1.5 in
Signs and symptoms
•large head with frontal bossing, depressed nasal bridge,
midfacial hypoplasia, narrow nasal passages, prognathism, and
•Generalized joint hypermobility, especially the knees
•Short fingers and bowed legs
-Large head of the affected infant may cause obstetrical problems
and also creates an increased risk of intracranial bleeding during
delivery (Hall et al, 1982).
-Marked obstetrical difficulties secondary to very narrow pelvis of
-Neurological complications including, small foramen
magnum, cervicomedullary junction compression causing sudden
unexpected death in infants with achondroplasia (Pauli et
al, 1984), apnea, communicating hydrocephalus, spinal
stenosis, paraparesis, quadriparesis, and infantile hypotonia
-Osteoarthropathy of the knee joints
Associations & support groups
•The Restricted Growth Association
•Little People of America group
•Association of Dwarfism