Here are some facts that people may not realize about dwarfism.
is characterized by short stature. This means an adult height of 4 feet 10 inches
or under, according to the advocacy group Little People of America (LPA). For children,
this means being below the height growth curve for their age, which would be less
than the 2nd percentile.
can and most often does happen in families where both parents are of average height
can be caused by any one of more than 400 conditions. Most of these are genetic
and classified as skeletal dysplasias (conditions of unusual
and bone growth).
The most common type of dwarfism is achondroplasia (prnounced:
an intellectual disability. Most people with dwarfism have normal intelligence.
a disease that requires a "cure." Most little people live long, fulfilling
a reason to assume someone is incapable. Little people go to school, work, drive
cars, marry, and raise children, just like their average-size peers.
What Causes Dwarfism?
Most types of dwarfism are caused by a genetic change (mutation) in the egg or
sperm cells before conception. Others happen because of genetic changes inherited
from one or both parents.
Depending on the type of dwarfism, two average-size parents can have a child with
short stature. It's also possible for parents who are little people to have an average-size
What Are the Types of Dwarfism?
Does everyone with dwarfism look alike? Not at all. Everyone with dwarfism is short,
but different types of dwarfism have different causes and different physical traits.
Most types of dwarfism are skeletal dysplasias (pronounced: diss-PLAY-zhee-uhs).
There are more than 400 different types of these unusual cartilage and bone growth
In general, dwarfism caused by skeletal dysplasias results in disproportionate
short stature. This means that the limbs and the trunk are not of the same
proportion as those of typically statured people.
The two types of this disproportion are short-trunk and short-limb:
People with short-trunk dwarfism have a shortened trunk with
more average-sized limbs.
People with short-limb dwarfism have a more average-sized trunk
with shortened arms and legs.
By far the most common skeletal dysplasia is achondroplasia. This
short-limb dwarfism happens in about 1 of every 25,000 babies born of all races and
ethnic groups. People with achondroplasia have a relatively long trunk and shortened
upper parts of their arms and legs. They also may have:
a larger head with a prominent forehead
a flattened bridge of the nose
shortened hands and fingers
a sway of the lower back
The average adult height for someone with achondroplasia is a little over 4 feet.
Diastrophic dysplasia is another short-limb dwarfism. It happens
in about 1 in 100,000 births. People who have this type tend to have shortened forearms
and calves (called mesomelic shortening). They might also have:
a cleft palate
ears with a cauliflower-like appearance
differently positioned thumbs (also called hitchhiker thumbs)
inward or downward pointing feet
spine curves that get worse over time
Most people with diastrophic dysplasia have joint problems that limit movement.
Along with the curved spine, this can make it hard to walk distances, especially when
they get older. Some people may need to use crutches, a scooter, or a wheelchair to
Spondyloepiphyseal dysplasias (SED) are short-trunk skeletal dysplasias
that involve the spine and the end of the bones that make up the joints (epiphyses).
Along with achondroplasia and diastrophic dysplasia, they're one of the more common
types of dwarfism. Someone with an SED also might:
have had clubfeet and/or a cleft palate at birth
have vision and/or hearing problems
have instability of the spine and/or curvatures that can get worse over time
develop reduced joint mobility and arthritis early in life
How Is Dwarfism Diagnosed?
Doctors can diagnose some cases of achondroplasia before birth by doing an ultrasound
in the later stages of pregnancy. The ultrasound can show if a baby's arms and legs
are shorter than average and if the baby's head is larger.
Different types of dwarfism can be diagnosed even earlier in pregnancy, but other
types aren't found until a baby is born. If it's thought a child may have dwarfism,
the doctor can use X-rays after birth to see if the bones are growing at an unusul
rate, or if they are shaped differently.
Possible Complications and Treatments
People with dwarfism can lead healthy, active lives. The conditions that cause
dwarfism have their own possible complications, which can change over time. But doctors
can treat many of these.
Some medical issues are treated with surgery, usually on the back, neck, leg, foot,
or middle ear. So, little people usually have more surgeries than the average-size
person, especially as children. These are done with anesthesia,
which can be more of a risk for little people because of their smaller body size and
A few extra pounds on a little person can be more of a problem than a few extra
pounds on an average-size person. Extra weight puts harmful stress on the back and
joints. Little people might have limits on the types of exercises and activities that
they can do. But it's important for them to find safe physical activities that they
enjoy to help stay fit.
What Else Should I Know?
Types of dwarfism, and their severity and complications, vary from person to person.
In general, a person's life span is not affected by being little. The Americans with
Disabilities Act protects the rights of people with dwarfism, but many members of
the short-statured community don't feel that they have a disability.
Most of the complications that happen in people with dwarfism are physical, not
intellectual. In fact, little people often find clever ways to do things in the average-size
world. They also interact with people unfamiliar with dwarfism who make assumptions
about it. While that can be tough and awkward at times, it's also an opportunity to
enlighten people who don't know much about dwarfism.