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Here are some facts that people may not know about 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.
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:
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:
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:
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:
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.
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.
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:
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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