A person with short stature, or restricted growth, does not grow as tall as other people of the same gender, age, and ethnicity. The person’s height is below the 3rd percentile.
Short stature can be a variant of normal growth, or it may indicate a disorder or condition.
Growth rate is an important indicator of overall health. Children who do not reach the 5th percentile by the age of 5 years are said to be small for gestational age (SGA). A pediatrician will look out for signs of “failure to thrive.”
Early intervention can prevent future problems in many cases.
Normally, at 8 years of age, a child’s arm span is around the same as their height. If these measurements are out of proportion, this may be a sign of disproportionate short stature (DSS), sometimes known as “dwarfism.”
Fast facts on short stature
Here are some key points about short stature. More detail is in the main article.
Short stature can happen for a wide range of reasons, including having small parents, malnutrition, and genetic conditions such as achondroplasia.
Proportionate short stature (PSS) is when the person is small, but all the parts are in the usual proportions. In disproportionate short stature (DSS), the limbs may be small compared with the trunk.
If short stature results from a growth hormone (GH) deficiency, GH treatment can often boost growth.
Some people may experience long-term medical complications, but intelligence is not usually affected.
Growth depends on a complex range of factors, including genetic makeup, nutrition, and hormonal influences.
Short stature can run in families or it can result from a hormone deficit or a genetic change.
The most common cause of short stature is having parents whose height is below average, but around 5 percent of children with short stature have a medical condition.
Conditions that can underlie short stature include:
undernutrition, due to a disease or lack of nutrients
hypothyroidism, leading to a lack of growth hormone
a tumor in the pituitary gland
diseases of the lungs, heart, kidneys, liver, or gastrointestinal tract
conditions that affect the production of collagen and other proteins
some chronic diseases, such as celiac disease and other inflammatory disorders
Sometimes, an injury to the head during childhood can lead to reduced growth.
A lack of growth hormone can also lead to delayed or absent sexual development.
Rheumatologic diseases, such as arthritis, are linked to short stature. This may happen because of the disease, or as a result of the glucocorticoid treatment, which can affect the release of growth hormone.
Disproportionate short stature (DSS) usually stems from a genetic mutation that affects the development of bone and cartilage and undermines physical growth.
The parents may not have short stature, but they may pass on a condition that is linked to DSS, such as achondroplasia, mucopolysaccharide disease, and spondyloepiphyseal dysplasia (SED).
Disproportionate short stature can result from a genetic condition.
An individual with DSS will be small in height, and they will have other unusual physical features. These may be visible at birth, or they may develop in time as the infant develops.
Most individuals will have an average-sized trunk and short limbs, but some people may have a very short trunk and shortened, but disproportionately large limbs. Head size may be disproportionately large.
Intelligence or cognitive abilities are unlikely to be affected unless the person has hydrocephalus, or too much fluid around the brain.
Achondroplasia underlies around 70 percent of cases of DSS. It affects around 1 in 15,000 to 1 in 40,000 people.