Dwarfism

Dwarfism is a condition marked by unusually small size or short stature, defined in humans as an adult height of 147 centimetres (4 feet 10 inches) or less, with average height among affected people around 120 centimetres. The condition divides into disproportionate dwarfism, where limbs or torso are shortened out of typical proportion, and proportionate dwarfism, where limbs and torso are both unusually small relative to typical stature. Causes include genetic disorders, most commonly achondroplasia which accounts for about 70 percent of cases, and hyposecretion of growth hormone from the pituitary gland. Intelligence is usually normal and most people with dwarfism have a nearly normal life expectancy and retain reproductive capacity, though pregnancy carries added risks depending on the underlying condition. Treatment varies by cause: genetic disorders may be managed with surgery or physical therapy, while growth hormone deficiency can be treated with hormone therapy administered before a child's growth plates fuse.