May also be called: Achondroplastic Dwarfism; Skeletal Dysplasia

What Is Achondroplasia?

Achondroplasia (ay-kon-druh-PLAY-zhee-uh) is a genetic disorder that that limits bone growth. It’s the most common cause of dwarfism (short stature).

As a baby develops in the womb, most of the skeleton is made up of a tough, flexible tissue called cartilage. Normally, cartilage  turns into bone by a process called ossification.

With achondroplasia, the body has a problem turning cartilage into bone, especially in the long bones of the arms and legs. This causes shorter bones —making kids shorter in height — and can also lead to a large head with a wide forehead. It can also cause knock-knees, bow-legs, or a curved lower back (lordosis or kyphosis).

What Else Should I Know?

Kids with this condition are more likely to develop hydrocephalus (fluid collecting around the brain), obesity, spinal stenosis (narrowing of the spinal canal), and other health conditions.

Regularly seeing a doctor or specialist is important for kids with achondroplasia to make sure they get the care they need to stay healthy.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.