What Is Dwarfism?

Here are some facts that people may not know about dwarfism.

• Dwarfism is characterized by short stature caused by changes in bone and cartilage growth.
• According to Little People of America (LPA), an advocacy group for people with dwarfism and their families, individuals with dwarfism reach a final height of 4 feet 10 inches or shorter.
• Most often, people with dwarfism are born to average-height parents.
• The most common type of dwarfism is achondroplasia (ay-kon-dreh-PLAY-zyuh).
• Most people with dwarfism have typical intelligence.
• Dwarfism is not a disease that requires a "cure." Just like their average-height peers, people with dwarfism go to college, drive cars, find meaningful jobs, get married, and have children.

What Causes Dwarfism?

There are over 700 different forms of skeletal dysplasia caused by genetic changes (mutations) that affect bone and cartilage growth. Many of these conditions result in short stature or dwarfism. Most often, genetic changes associated with various forms of dwarfism happen randomly, either before pregnancy (in the sperm or egg) or at the start of pregnancy (conception). Sometimes, dwarfism happens because a child inherited a genetic change(s) from one or both parents There is nothing a parent could do before or during pregnancy to prevent this change.

A genetic counselor can help determine someone's chances of having a child with dwarfism.

What Are the Types of Dwarfism?

Individuals with dwarfism all have short stature. But there are many different causes of dwarfism. Each has their own unique features and physical traits.

In general, dwarfism is caused by a skeletal dysplasia that results in disproportionate short stature. This means that the limbs (arms and legs) and the trunk are not of the same proportion as those of average-height individuals.

The two types of this disproportion are short-trunk and short-limb:

• Short-trunk dwarfism: The torso is shortened when compared with the limbs.
• Short-limb dwarfism: The limbs are shortened when compared with the trunk.

Achondroplasia is the most common form of dwarfism. It happens in about 1 in 25,000 people of all races and ethnic groups. People with achondroplasia have a relatively long trunk and shortened arms and legs. This is most noticeable in the upper parts of their arms and legs (called rhizomelic shortening).

Other common features may include:

• a larger head with a prominent forehead
• a flattened bridge of the nose
• shortened hands and fingers
• a sway of the lower back
• bowed legs

The average adult height for someone with achondroplasia is around 4 feet tall.

Diastrophic dysplasia is another form of short-limb dwarfism. It happens in about 1 in 100,000 births. Shortening is most noticeable in the bones in the lower parts of the arms and legs (called mesomelic shortening).

Other common features can include:

• cleft palate
• changes in the outer ear (also known as a cauliflower-like appearance)
• differences in thumb position (also called hitchhiker thumbs)
• clubfeet (inward or downward pointing feet)
• spine curves that can change over time

Most people with diastrophic dysplasia have joint changes that limit movement. People with diastrophic dysplasia often benefit from mobility aids, such as crutches, a scooter, or a wheelchair to get around.

Spondyloepiphyseal dysplasias (SED) are short-trunk skeletal dysplasias that involve the spine and the end of the bones that make up the joints (epiphyses). In one type of SED, the short trunk may not be noticed until the child is school age. Other types are seen at birth.

Other common features can include:

• clubfeet
• cleft palate
• vision and/or hearing differences
• instability of the spine and/or curves in the spine that change over time
• reduced joint mobility and arthritis early in life

How Is Dwarfism Diagnosed?

Most pregnant women have a prenatal ultrasound to measure the baby's growth at around 20 weeks. At that stage, features of achondroplasia aren't yet noticeable. Doctors sometimes suspect achondroplasia before birth if an ultrasound late in a pregnancy shows that a baby's arms and legs are shorter than average and the head is larger. But many children with achondroplasia aren't diagnosed until after birth.

Doctors can recognize some other types of skeletal dysplasia earlier in pregnancy. Others aren't noticed until the first few months or years of life, when a child's growth slows. A health care provider may take X-rays after birth to check for bone changes. Doctors also may use genetic testing before or after birth to confirm the diagnosis.

Possible Problems and Treatments

Each condition that causes dwarfism has its own possible medical complications, which can change over time. 

Individuals with dwarfism may receive care from doctors who specialize in orthopedics, neurosurgery, ENT, pulmonology, and genetics/skeletal dysplasia. Some medical concerns  require surgery. It is important that surgery be performed at a children’s hospital with access to pediatric anesthesiologists if complications were to occur.

Because of their shorter stature and differences in bone growth, children with dwarfism often learn to roll over, sit up, and walk at different ages than average-height children. These are not considered delays, but developmental differences. Children with dwarfism figure out how to do these things in their own time and in their own way.

People with dwarfism should try to keep a healthy weight. A few extra pounds can put harmful stress on the back and joints.

How Can Parents Help?

People with dwarfism can lead healthy, active lives. The Americans with Disabilities Act protects their rights.

Types of skeletal dysplasia and the severity of medical needs vary from person to person. In general, with proper medical care, life span is not affected by having dwarfism.

It is important to promote a sense of independence and self-esteem right from the start.

Here are some general tips to keep in mind:

• Treat your child according to their age, not their size, and encourage others to do the same. A 2-year-old shouldn't use a bottle, even if they're the size of a 1-year-old. If you expect your 6-year-old to clean up their room, do not make an exception because your child is small.
• Make changes to your child's environment to promote independence. Simple, inexpensive options include light switch extenders or a step-stools.
• Treat your child's skeletal dysplasia as a difference, not a problem. Your attitude and expectations can greatly influence your child's self-esteem.
• Ask how your child wants to refer to their dwarfism. Some people prefer "little person" or "person of short stature."
• Try your best to stay calm and positive when responding to other people's reactions. Address questions or comments as directly as possible, then point out something special about your child. Your child will see that you notice the qualities that make them unique. This helps prepare your child for responding to these situations when you're not there.
• If your child is teased at school, don't overlook it. Talk to teachers and administrators to make sure your child is getting support they need. Offer to work with the school to educate others about dwarfism.
• Help your child learn about their condition and possible health care needs as your child gets older and more independent.
• Encourage your child to find a hobby or activity to enjoy. Check with your doctor about any sports to avoid. Music, art, computers, writing, or photography are also wonderful options to explore.
• Stay active together as a family. If needed, choose or adapt the activity so your child can join.
• Refer family and friends to websites that can help them learn about dwarfism, such as:
  • Understanding Dwarfism
  • Little People of America
• Find support from groups like Little People of America. Getting to know other people with dwarfism — both as peers and mentors — can show kids how much they can achieve.