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Medical information - Achondroplasia
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Achondroplasia is a rare, genetic condition, but one of the most common types of restricted growth with disproportionate short stature. Achondroplasia is mainly a physical condition with affected people having normal intelligence.
Many practical difficulties can be overcome with a little imagination and there is no reason why someone with achondroplasia should not participate in most activities. It is important that the person themselves is able to find their own limits and boundaries and that these are not imposed by society.
Achondroplasia literally means 'no cartilage growth,' but in reality it refers to poor bone growth resulting in shortened limbs. The tissues around the limbs are not affected and continue to grow leading to bulky arms and legs. Growth charts designed specifically for children with achondroplasia should be used to monitor growth.
People with achondroplasia have a range of characteristics including:
- A near normal trunk length with shorter arms and legs
- A large head with prominent forehead and flattened bridge of the nose
- An increased curvature of the lower spine (lumbar lordosis)
- Bowing of the lower legs
- Possible crowded teeth
- Short, broad feet and hands with separation between middle and ring fingers (the 'trident' hand)
- Exceptionally flexible joints
Babies with achondroplasia may develop motor skills and mobility more slowly than normal because of the combination of a heavier head and shorter arms and legs, but ultimately development is within the expected normal range.
Some medical complications are associated with achondroplasia:
- Glue ear / hearing impairment
- Glue ear / hearing impairment
- Breathing problems in young children
- Hydrocephalus
- Spinal stenosis leading to compression of nerves to the limbs
- Joint problems due to leg bowing
Most of these affect only a minority of people with the condition.
People with achondroplasia have a normal life expectancy.
Most people with achondroplasia are born to average size parents. Achondroplasia is due to a change in the gene that codes for Fibroblast Growth Factor Receptor 3. (FGFR3). In almost all cases the single base change is exactly the same. The estimated prevalence is 1 in 25,000.
Average size parents of a child with achondroplasia have very small chance of having another child with the condition.
In adults with achondroplasia the inheritance pattern is autosomal dominant.
Ultra sound scans may detect disproportionately short limbs at around 25 weeks of pregnancy. For couples where one or both has the condition, a chorionic villus sampling test is available at 12 weeks of pregnancy.
Disclaimer: The information on this website is to be used for informational and educational purposes only and is not to be used to replace personal consultation with a qualified health professional that is familiar with your individual medical needs. Always consult with a doctor, health-care provider, or therapist before making any medical decisions.
