This website is intended for residents of the U.S. interested in achondroplasia

A Closer Look at Achondroplasia

Bones play an important role in mobility, daily functioning, and overall health. In achondroplasia, bone growth is slowed or inhibited. Explore how achondroplasia occurs, the different ways it can affect individuals throughout life, and how you can support healthy development with the right care.

WHAT IS ACHONDROPLASIA?

Achondroplasia is the most common type of skeletal dysplasia, with about 250,000 people diagnosed worldwide. Skeletal dysplasias are rare genetic conditions that affect bone and cartilage development.

A rare genetic condition that inhibits bone growth

Bone growth

Most bones begin as cartilage. The process of cartilage developing into bone is known as endochondral bone growth.

Growth plates

Located at the ends of bones, growth plates are where endochondral bone growth takes place. They remain open from before birth until late adolescence or early adulthood (around ages 15 to 20 years). Once growth plates close, endochondral bone growth stops.

Inhibited bone growth

In achondroplasia, endochondral bone growth is inhibited in over 90% of bones in the body during developmental years.

The most significant bone growth in the skull, spine, and chest happens during a child’s first 7 years—especially from birth to 5 years old.

HOW DOES INHIBITED BONE GROWTH AFFECT HEALTH?

When bone growth is inhibited, there’s less space inside the body for organs and nerves. For some people with achondroplasia, this can lead to developmental and health issues that have a lasting impact.

Inhibited bone growth can affect health in different ways

  • Smaller ear canals
    Can cause frequent ear infections, leading to hearing issues and speech delay
  • Smaller opening at the base of the skull
    Can cause compression of the spinal cord, leading to nerve or breathing issues (foramen magnum stenosis)
  • Narrow airways
    Can contribute to sleep apnea
  • A smaller ribcage
    Can affect the lungs and breathing
  • A narrow backbone
    Can cause compression of the spinal cord (spinal stenosis)
  • Shorter limbs and stature
    Can impact daily function

See care recommendations

FIND SPECIALIZED CARE

Because achondroplasia is rare, it may be difficult to find doctors with the experience you need. Feel confident you’re finding specialized care for your child.

FIND CARE NEAR YOU

SUPPORT EVERY STEP OF THE WAY

Over the course of their life, your child may develop unique needs that require additional consideration from their pediatrician or other specialists. Working closely with your healthcare team and keeping an open dialogue can help you be prepared and provide the right support at the right time.

Photo of a child with a healthcare provider

Tracking physical development

During your child’s visits to their pediatrician, their growth and development should be tracked using achondroplasia-specific growth charts. If certain physical measures like weight or head size are not within the expected range outlined in these charts, your child’s doctor may recommend some additional care and support considerations.

Photo of an infant with Achnodroplasia playing with a ball

Monitoring language and motor skills

All children grow at their own pace, which means they may reach certain milestones at different times. Most children with achondroplasia will meet expected language milestones; however, frequent ear infections due to inhibited bone growth in ear canals can lead to hearing issues and delay speech development.

Similarly, children with achondroplasia may experience delayed motor skills (such as rolling over, sitting, crawling, and walking) or develop these skills in their own way (moving with the support of their head or bottom, army crawling, rolling, scooting, and more).

Photo of a child with Achondroplasia cooking in a kitchen

Promoting independence

With guidance from your healthcare team, you can help your child become more self-sufficient. Support their independence by creating an environment that’s accessible, safe, and tailored to their specific needs. Learn more about adaptions and tips that can help your child at home, school, and out in the world.

Achondroplasia growth charts

An important tool to track, predict, and evaluate growth.

Download charts

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