Achondroplasia
Condition
(Achondroplastic Dwarfism)
Definition
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
ACH may be caused by:
- Changes in the FGFR3 gene
- Advanced age of father
Risk Factors
ACH 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.
Symptoms
ACH is often seen at birth. Key features are a large head, short limbs, a narrow chest, and short fingers.
A person with ACH may also have:
- Short stature—adult height will be 4 to 4½ feet
- Bowlegs
- Short toes
- Parts of the face that are not fully developed
- Arms that may not be fully straight at the elbow
- An excessive lower back curve
Diagnosis
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.
Treatment
The goal of treatment is to manage any related health problems. There is no cure for ACH. Choices are:
- Medicine such as human growth hormone and vosoritide 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
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Prevention
ACH cannot be prevented.
Healthy Children—American Academy of Pediatrics
Little People of America
CANADIAN RESOURCES:
Caring for Kids—Canadian Paediatrics Society
Little People of Ontario
Healthy Children—American Academy of Pediatrics
Little People of America
CANADIAN RESOURCES:
Caring for Kids—Canadian Paediatrics Society
Little People of Ontario
References
- Achondroplasia. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/achondroplasia.
- Achondroplasia. Genetic and Rare Diseases Information Center website. Available at: https://rarediseases.info.nih.gov/diseases/8173/achondroplasia.
- Legare, J.M. Achondroplasia. GeneReviews, 2022. Available at: https://www.ncbi.nlm.nih.gov/books/NBK1152.
- 5/25/2022 EBSCO DynaMed Systematic Literature Surveillance https://www.dynamed.com/condition/achondroplasia: FDA approves first drug to improve growth in children with most common form of dwarfism. US Food and Drug Administration website. Available at: https://www.fda.gov/news-events/press-announcements/fda-approves-first-drug-improve-growth-children-most-common-form-dwarfism.
Contributors
- James P. Cornell, MD
(C) Copyright 2022 EBSCO Information Services
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