by EBSCO Medical Review Board
(Achondroplastic Dwarfism)


Achondroplasia (ACH) is a genetic bone disorder. It is the most common type of dwarfism. Key features are a large head, short limbs, a narrow chest, and short fingers.


Causes may be:

  • Changes in the FGFR3 gene
  • Advanced age of father

Risk Factors

This problem can happen in people who do not have any known risk factors.

The gene changes can also be passed through a family, though this is not as common.


Problems are often seen at birth. Key features are a large head, short limbs, a narrow chest, and short fingers.

Other problems may be:

  • Short stature—adult height will be 4 to 4½ feet
  • Bowlegs
  • Short toes
  • Underdeveloped parts of the face
  • Arms that may not be fully straight at the elbow
  • An excessive lower back curve


A prenatal ultrasound may point to ACH. Genetic testing may be done to confirm it.

ACH may also be suspected during a physical exam at birth. It can be confirmed through x-rays. Rarely, genetic testing may be done if the exam and x-rays are not certain.


There is no cure. The goal of treatment is to manage related health problems. Choices are:

  • Medicine, such as human growth hormone to increase adult height
  • Surgery to treat health problems, such as:
    • Spinal fusion to connect spinal bones to make them more stable
    • Laminectomy to remove parts of spinal bones to ease pressure on the spinal cord
    • Osteotomy to repair severe bowlegs
    • Bone lengthening to cut and divide a bone to encourage more growth
  • Counseling and support groups
Spinal Stenosis
Stenosis of spine with punched nerve
Copyright © Nucleus Medical Media, Inc.


There are no known guidelines to prevent ACH.


Healthy Children—American Academy of Pediatrics 

Little People of America 


Caring for Kids—Canadian Paediatrics Society 

Little People of Ontario 


Achondroplasia. EBSCO DynaMed website. Available at: Accessed October 29, 2020.

Achondroplasia. Genetic and Rare Diseases Information Center website. Available at: Accessed October 29, 2020.

Pauli RM, Legare JM. Achondroplasia. GeneReviews 2018 May 10.

Revision Information

  • Reviewer: EBSCO Medical Review Board James P. Cornell, MD
  • Review Date: 09/2020
  • Update Date: 04/28/2021