A person with short stature, or restricted growth, does not grow as tall as other people of the same sex, 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 condition.
If a child’s limbs are disproportionate to their height or the child is shorter than average, this is called disproportionate short stature (DSS).
The most common cause of DSS is achondroplasia, a type of dwarfism. A caregiver can talk with the child’s doctor to verify that their height is appropriate for their age.
In many cases, early intervention can prevent future issues.
Fast facts on short stature
Here are some key points about short stature:
- Short stature can happen for many reasons, including having short parents, malnutrition, and genetic conditions, such as achondroplasia.
- Proportionate short stature (PSS) is when the person is short but all body parts are in usual proportions. In disproportionate short stature (DSS), the limbs may be short compared with the trunk.
- If short stature results from a growth hormone deficiency, 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.
Growth rate is an important indicator of overall health. Children born at the 10th percentile or less for gestational age (length of pregnancy) are said to be small for gestational age. If a child is under the 5th percentile or their growth rate is declining, a pediatrician looks for signs of failure to thrive.
The World Health Organization (WHO) developed
For example, if a child is in the 10th percentile for weight, that means 10% of other children weigh less, and 90% weigh more.
The most common cause of short stature is having parents whose height is below average, but a small percentage of children have a medical cause for their short stature.
There are several genetic conditions that can lead to short stature,
- Noonan syndrome
- Turner syndrome
- Prader-Willi syndrome
- Down syndrome
- achondroplasia
Health 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 conditions
- mitochondrial disease, which can affect the body in different ways, including growth
A lack of growth hormone (GH) can also lead to delayed or absent sexual development.
Rheumatologic diseases, such as arthritis, are also
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 linked to DSS, such as:
- achondroplasia
- mucopolysaccharide disease
- spondyloepiphyseal dysplasia
There are many types and causes of short stature. Each presents differently. Because the range of conditions is so broad, restricted growth can be classified in various ways.
One categorization is:
- proportionate short stature (PSS)
- disproportionate short stature (DSS)
Each category includes a number of causes of short stature.
Proportionate short stature (PSS)
The most common cause of short stature is normal variants of growth.
Sometimes, a related health condition restricts overall growth, but the trunk and limbs are in proportion. This is known as PSS.
In most cases of PSS, the person’s parents are also small, but sometimes it occurs because the body does not produce enough GH, or the body does not process GH properly. This is known as GH insensitivity.
Children with GH insensitivity also have short stature. GH insensitivity is a set of rare genetic conditions caused by mutations in the GH receptor, in which the body cannot use the GHs it has produced. GH treatment during childhood may help.
Hypothyroidism can lead to low hormone production. For children with juvenile hypothyroidism, short stature is
If the person’s body weight is higher than typical for their height, this can suggest a hormone problem. The problem could be hypothyroidism, excess glucorticoid production, or too little GH.
Familial short stature
Sometimes a person’s body is small but otherwise healthy. If their parents are also small, this can be called familial short stature (FSS).
The limbs and the head develop in proportion with the spine, and the person is otherwise healthy.
Growth happens throughout the body, so the legs, for example, are in proportion with the spine.
Constitutional delay in growth and adolescence
If short stature stems from a hormonal issue, it is called a constitutional delay in growth and adolescence (CDGA).
Other causes for delayed growth
A person whose body is small and whose weight is lower for their height may be experiencing malnutrition, or they may have a condition that leads to malabsorption.
Whatever the underlying reason, if it affects overall growth, it may impair development in at least one body system, so treatment is needed.
During adulthood, a person with PSS is more likely to experience:
- osteoporosis
- cardiovascular problems
- reduced muscle strength
Rarely, there may be problems with thinking. This depends on the cause of the short stature.
Genetic conditions, including Turner syndrome, Down syndrome, or Prader-Willi syndrome, can also cause PSS.
Disproportionate short stature (DSS)
DSS is linked to a genetic mutation. The parents are usually of average height. As with other types of short stature, a range of underlying causes is possible.
A person with DSS will be short in height and have different physical features, such as a disproportionately large head. These may be visible at birth, or they may develop later as the infant develops.
Most people with DSS have an average-size trunk and short limbs, but some people may have a very short trunk and shortened but disproportionately large limbs and head.
Intelligence or cognitive abilities are unlikely to be affected unless the person with DSS also has hydrocephalus, or too much fluid around the brain.
Achondroplasia is the cause of
Features of DSS include:
- an average-size trunk
- short limbs
- short fingers, possibly with a wide space between the middle and ring fingers
- limited mobility in the elbows
- a large head with a prominent forehead and flattened nose bridge
- bowed legs
- lordosis, which is a progressive development of a swayed lower back
- average adult height of 4 feet (122 centimeters)
Hypochondroplasia is a
Achondroplasia and hypochondroplasia also result from a genetic mutation.
Doctors can diagnose some types of short stature at birth. In other cases, routine visits to a pediatrician can reveal any atypical growth pattern.
During a routine visit, a pediatrician will record the child’s head circumference, height, and weight.
If they suspect restricted growth, they will do a physical examination, look at the child’s medical and family history, and possibly order some tests.
These tests may include:
- X-ray: This imaging test assesses for problems with bone development.
- Insulin tolerance test: This test checks for a deficiency in insulin-like growth factor-1 (IGF-1). In this test, insulin is injected into a vein, causing blood glucose levels to drop. Normally, this would trigger the pituitary gland to release GH. If GH levels are lower than normal, there may be a GH deficiency.
Other tests include:
- a thyroid-stimulating hormone test to check for hypothyroidism
- a complete blood count to test for anemia
- metabolic tests to assess liver and kidney function
- erythrocyte sedimentation and C-reactive protein tests to assess for inflammatory conditions
- urine tests to check for enzyme deficiency disorders
- tissue transglutaminase and immunoglobulin A tests to check for celiac disease
- other imaging scans, such as an MRI, to detect problems with the pituitary gland or hypothalamus
- bone marrow or skin biopsies to help confirm conditions associated with short stature
Treatment depends on the cause of the short stature.
Malnutrition
If there are signs of malnutrition, the child may need nutritional supplements. In some cases, they may need treatment for a bowel disease or other condition that is preventing their body from absorbing nutrients.
Hormonal issues
If growth is restricted or delayed because of a hormonal problem, GH treatment may be necessary.
Pediatric hormone treatment
In children who produce too little GH, a daily injection of hormone treatment may stimulate physical growth later in life. Medications, such as somatropin, may eventually add 4 inches (10 centimeters) to adult height.
Adult hormone treatment
GH treatment after growth is complete will not increase an adult’s height. However, treatment can help protect against complications, such as cardiovascular disease and low bone mineral density.
Somatropin, also known as recombinant GH, might be recommended for adults who:
- have a severe GH deficiency
- experience impaired quality of life
- are already receiving treatment for another pituitary hormone deficiency
Adults can generally self-inject the medication daily.
Side effects of somatropin include:
- headache
- muscle pain
- edema
- fluid retention
- problems with eyesight
- joint pain
- vomiting
- nausea
The person may also receive treatment to manage chronic conditions, such as heart disease, lung disease, and arthritis.
Treatment for DSS
Because DSS often stems from a genetic condition, treatment focuses on managing any symptoms and complications.
Some people with very short legs may undergo leg lengthening surgery. During the surgery, the leg bone is broken and then fixed into a special frame. The frame is adjusted daily to lengthen the bone.
This does not always work, though. It also takes a long time, and there is a risk of complications, including:
- pain
- the bone forming badly or at an inappropriate rate
- infection
- deep vein thrombosis (DVT)
Other possible surgical treatments include:
- use of growth plates, where metal staples are inserted into the ends of long bones where growth takes place to help bones grow in the right direction
- inserting staples or rods to help the spine form the right shape
- increasing the size of the opening in the bones of the spine to reduce pressure on the spinal cord
Regular monitoring from a doctor can reduce the risk of complications.
Complications from DSS include:
- arthritis later in life
- delayed mobility development
- dental problems
- bowed legs
- hearing problems and otitis media
- hydrocephalus, or too much fluid in the brain cavities
- hunching of the back
- limb problems
- swaying of the back
- narrowing of the channel in the lower spine during adulthood and other spine problems
- sleep apnea
- weight gain
- speech and language problems
In PSS, people may have poorly developed organs, which can cause pregnancy complications, such as respiratory problems. Cesarean delivery is likely if a person is pregnant.
Most people with short stature have a normal life expectancy.
The chance of a child with short stature reaching a typical adult height depends on the cause of the short stature. For conditions responsive to GH, GH treatment may help attain a taller height in adulthood, but it may be expensive and may have side effects.
In other cases, a typical adult height will not be reached due to conditions such as Prader-Willi syndrome or Down syndrome.
A person with achondroplasia can also expect a normal life span.
If a person has any questions about managing health conditions related to short stature, they can reach out to a doctor for advice and support.