What Is Dwarfism?
Here are some facts that people may not realize about dwarfism.
- is characterized by short stature. According to Little People of America (LPA), an advocacy group for people with dwarfism and their families, this means a final height of 4 feet 10 inches or less.
- can and most often does happen in families where both parents are of average height
- is often caused by one of over 400 skeletal dysplasias (diss-PLAY-zhee-uhs). These affect bone and growth, and often lead to disproportional short stature.
The most common type of dwarfism is achondroplasia (ay-kon-dreh-PLAY-zyuh).
Dwarfism is not:
- an intellectual disability. Most people with dwarfism have typical intelligence.
- a disease that requires a "cure." Most individuals with dwarfism live long, fulfilling lives.
- a reason to assume someone is incapable. Individuals with dwarfism go to school, work, drive cars, marry and raise children, just like their average-height peers.
What Causes Dwarfism?
Most types of dwarfism are caused by a genetic change (mutation) in an egg or sperm cell that happens before the start of pregnancy (conception). Others happen because of a genetic change(s) inherited from one or both parents. Genetic changes happen randomly. There is nothing a parent could do before or during pregnancy to prevent this change from happening. A genetic counselor can help determine the chances of having a child with dwarfism.
Depending on the type of dwarfism, two average-height parents can have a child with short stature. It's also possible for two parents with dwarfism to have an average-height child.
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 caused by a skeletal dysplasia results in disproportionate short stature. This means that the limbs (arms and legs) and the trunk are not of the same proportion as 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.
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 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 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
- changes in the outer ear (also known as a cauliflower-like appearance)
- differently positioned thumbs (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). Along with achondroplasia and diastrophic dysplasia, they're one of the more common types of dwarfism. In one type of SED, the short trunk may not be noticed until the child is school age. Other types are seen at birth.
Kids with an SED also might:
- be born with clubfeet and/or cleft palate
- have vision and/or hearing differences
- have instability of the spine and/or curves in the spine that change over time
- develop 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 Complications and Treatments
Each condition that causes dwarfism has its own possible medical complications, which can change over time. But doctors can treat many of these.
Children with dwarfism are cared for by doctors who specialize in orthopedics, neurosurgery, ENT, and pulmonology. Some medical concerns are treated with surgery. These are done with anesthesia, which can be more of a risk for little people because of their smaller body size and airways.
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 it in their own time and in their own way.
People with dwarfism should try to keep a healthy weight. A few extra pounds can puts harmful stress on the back and joints. It's important for them to find safe and enjoyable physical activities.
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 dwarfism.
Parents can help their kids lead the best life possible by building their 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 and developmental level, not their size. A 2-year-old should not still use a bottle, for example, even if she's the size of a 1-year-old. And, if you expect a 6-year-old to clean up his room, don't 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:
- 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.
- Dwarfism: Emily's Story (Video)
- Prenatal Tests: FAQs
- Genetic Testing
- Newborn Screening Tests
- Physical Therapy
- Dwarfism Factsheet (for Schools)
- Occupational Therapy