What is Achondroplastic Dwarfism?

Achondroplastic dwarfism is a type of genetic disorder that is responsible for short stature and related health complications. About 70 percent of all people with dwarfism have the achondroplastic variety. The condition is characterized by short arms and legs and an abnormally large cranium. Many individuals experience also spine problems in late childhood or as adults due to congenital deformities. With the proper medical care and support, most people with achondroplastic dwarfism are able to enjoy long, fulfilling, productive lives in society.

Doctors have identified a particular gene on chromosome four that appears to be responsible for achondroplastic dwarfism in the vast majority of cases. A mutation in the fibroblast growth factor receptor-3 gene results in abnormal bone and muscle tissue development in a fetus. The condition has an autosomal dominant pattern, meaning that a fetus can inherit the condition if just one parent carries the defective gene. Spontaneous mutations can occur as well, and many people with dwarfism have no family history of the disorder. The only well-documented risk factor for having a baby with spontaneous dwarfism is being a male over the age of 35 at the time of conceiving a child.

Infants who have achondroplastic dwarfism typically have large heads and very low muscle tone, which often makes it difficult for them to hold their necks in an upright position. Mild to severe spine curvature resulting a hunchbacked appearance is present in many cases as well. As children get older, muscle tone tends to improve, but they still have disproportionately large heads and short extremities. The legs tend to bow outward, and the elbows have limited mobility. Adults with achondroplastic dwarfism typically stand about 4 feet (122 centimeters) tall.

The main concern for doctors when confronted with achondroplastic dwarfism is correcting major spine problems. An infant with a severe curvature may need a series of surgeries to realign and fuse vertebrae together. If the degree of curvature is moderate, surgery by be delayed until adolescence, when bone development is more complete.

Some patients are treated with human growth hormone (HGH) injections during childhood to promote better bone growth. Long-term use of HGH is somewhat controversial in medicine, however, and many studies fail to show real benefits for people with achondroplastic dwarfism. An adult patient who is very concerned about his or her appearance may elect to undergo a surgical limb lengthening procedure. The surgery involves separating sections of leg and arm bone and placing metal rods and screws between them. The procedure is risky and unnecessary, so most professionals advise against it.

Dwarfism can certainly pose physical challenges and self-esteem issues, but a positive outlook and emotional support from loved ones can help a person achieve his or her life goals. Special accommodations can be arranged to make school, work, home life, and driving much easier for a person of short stature. Online and community support groups also can help people better understand their conditions, develop friendships, and learn important tips on self-sufficient living.