What Is Cartilage Hair Hypoplasia?

Cartilage hair hypoplasia is a skeletal dyplasia. Skeletal dysplasias are conditions that cause problems with how and bone grow.

Cartilage hair hypoplasia (hye-poe-PLAY-zhuh) also leads to problems with the immune system (the body’s germ-fighting system).

With regular medical care, most kids with cartilage hair hypoplasia can live a full, healthy life.

What Are the Signs & Symptoms of Cartilage Hair Hypoplasia?

The symptoms of cartilage hair hypoplasia include:

• dwarfism (height less than 4 feet, 10 inches [145 cm] as an adult)
• fine, sparse, light-colored hair, eyebrows, and eyelashes
• short bones in the arms and legs
• sternum (breastbone) that sticks out
• elbows that won’t go completely straight
• flexible joints
• bow legs (knees curve out)
• knock-knees (knees curve in)
• scoliosis (curved backbone)
• immunodeficiency (a weak immune system)
• gastrointestinal problems
• increased risk of skin cancer and blood cancer

Cartilage hair hypoplasia does not affect thinking and learning abilities.

What Causes Cartilage Hair Hypoplasia?

Cartilage hair hypoplasia happens because of a gene mutation (change). Many different mutations can lead to the condition, and each causes different symptoms.

Cartilage hair hypoplasia is an inherited condition. Children who have it got one changed gene from each parent. Children who get one gene from one parent don’t have symptoms, but they can pass the changed gene to their children.

A genetic counselor can help families understand how the condition can run in families.

How Is Cartilage Hair Hypoplasia Diagnosed?

Most children with cartilage hair hypoplasia are diagnosed around their first birthday. To make a diagnosis, doctors do an exam and might order tests such as:

• X-rays to look for bone problems
• blood tests to check the immune system
• genetic testing

How Is Cartilage Hair Hypoplasia Treated?

A team of medical specialists cares for people who have cartilage hair hypoplasia. They can include:

• an orthopedic surgeon: to treat bone and joint problems with bracing and surgery
• a neurologist/neurosurgeon: for brain, spinal cord, and nerve problems
• a genetics doctor: to help families understand the genetic changes
• an immunologist: to watch for and treat immune problems
• a hematologist: to check for blood problems
• a dermatologist: to check the skin regularly for skin cancer
• a pediatrician: for routine care
• a physical therapist: for help with muscle strength and joint motion
• an occupational therapist: for help with writing, eating, and other everyday activities

How Can Parents Help?

Children with cartilage hair hypoplasia can have symptoms that range from mild to severe. Regular medical care can help your child stay well and manage any problems. Be sure to:

• Go to all doctor visits.
• Give any medicines as prescribed.
• Call your doctor as instructed.

Also:

• Treat your child according to their age, not their size, and encourage others to do the same.
• Talk about cartilage hair hypoplasia as a difference rather than a problem. Your attitude can help your child develop good self-esteem.
• Find ways to adapt. For example, get a light switch extender and a stepstool so your child can turn the lights on and off. Encourage your child’s school to make similar changes to help your child, such as lower chairs and/or feet support.
• Answer questions as simply as possible. If someone asks why your child is short, for example, say, “Jason is shorter because he has a problem with his bones.” Then, mention something special about your child. For example, “Nothing holds Jason back. He loves to sing.” This shows your child that many things make them special.
• Teach your child that being teased or bullied is not OK. If your child is teased or bullied at school, work with your child, teachers, and administrators to end it.
• Encourage your child to find a hobby or activity to enjoy. Help your child try different activities like music, art, computers, writing, and photography.

What Else Should I Know?

To find support, talk to anyone on the care team or a hospital social worker about resources that can help you and your child.

Support groups also can be helpful for kids and their families. Ask the care team for recommendations. You also can find support and more information online at:

• Little People of America
• Genetic Alliance