A to Z: Achondroplasia

May also be called: Achondroplastic Dwarfism; Skeletal Dysplasia

Achondroplasia (ay-kon-druh-PLAY-zhee-uh) is a genetic disorder that interferes with bone growth and causes dwarfism (short stature).

More to Know

During a baby's development in the womb, much of the skeleton is made up of a tough, flexible tissue called cartilage. Normally, cartilage is converted to bone by a process called ossification. With achondroplasia, the body has a problem growing cartilage and converting it to bone, especially in the long bones of the arms and legs. This results in shorter bones, short stature, and often a large head with a prominent forehead. It can also cause knock-knees, bow-leggedness, or excessive curving of the lower back (lordosis or kyphosis).

Achondroplasia is the most common cause of dwarfism. It happens because of a mutation in a gene that develops and maintains bone tissue. Achondroplasia can be inherited from a parent, but in most cases, the mutation in the gene happens at random. Most people with achondroplasia have normal-sized parents.

Since achondroplasia is due to a genetic mutation, those who have it may pass it on to their children. It can be diagnosed prenatally by ultrasound or genetic testing. There is no specific treatment for achondroplasia, but treatment might be necessary if it leads to complications such as hydrocephalus (fluid collecting around the brain), obesity, or spinal stenosis (narrowing of the spinal canal).

Keep in Mind

There is no cure for achondroplasia, but it does not affect a person's intellectual ability or life span.

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