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Achondroplasia - Achondroplasia symptom, treatment, causes

Achondroplasia is an inherited disorder in which the growth plate of cartilage near the ends of the long bones of the limbs is converted to bone too early in childhood, resulting in shortened arms and legs but a normal skull and spine - a type of DWARFISM. Achondroplasia is a disorder of bone growth. Although achondroplasia literally means "without cartilage formation," the problem in achondroplasia is not in forming cartilage but in converting it to bone, particularly in the long bones.

Achondroplasia is a distinctive condition that usually can be noted at birth. It is a common cause of dwarfism. Children with this condition have a tendency towards middle-ear infections this may happen until five or six years of life, this may be due to abnormal drainage from the tube that leads from the middle ear to the throat. Achondroplasia is a result of an autosomal dominant mutation in the fibroblast growth factor receptor gene 3, which causes an abnormality of cartilage formation. People with this condition have short stature, usually reaching a full adult height of around 4 feet or 1.2 meters. People with achondroplasia have one normal copy of the fibroblast growth factor receptor 3 gene and one mutant copy. Two copies of the mutant gene are invariably fatal before, or shortly after birth. Only one copy of the gene needs to be present for the disorder to occur. It is the most common cause of short stature with disproportionately short limbs.

A family history of achondroplasia should alert parents to the possibility of having an affected child. There are two other syndromes with a genetic basis similar to achondroplasia: hypochondroplasia and thanatophoric dysplasia. Because of short stature, obesity is often associated with the disease. Weight control is a frequent and lifelong problem for many people with this disorder. Both children and adults must be careful of their nutrition because they are prone to add excess weight. Infants and children with achondroplasia should be thoroughly evaluated for skeletal abnormalities by a doctor experienced with the disorder. The genetic defect can be passed from a parent to his or her child. There is no specific treatment for achondroplasia. Related abnormalities, including spinal stenosis and spinal cord compression, should be treated when they cause problems.

When a child with Achondroplasia is born to normal parent, the abnormallity has arisen from a gene mutation that is past on to half of the affected person's children. The majority of achondroplasia cases (80 percent), however, are the result of a new mutation in the family - the parents are of average height and do not have the abnormal gene. Achondroplasia may be inherited as an autosomal dominant trait, which means that if a child gets the defective gene from one parent, the child will have the disorder.

Symptoms of Achondroplasia

Here is the list of some of the common sign and symptoms of Achondroplasia. The symptoms of achondroplasia may resemble other problems or medical conditions. Always consult your child's physician for a diagnosis.

• Short stature
• Short limbs (upper arm and thigh)
• Skeletal (limb) abnormalities
• Abnormal hand appearance
• Marked kyphosis and lordosis (spine curvatures)
• Waddling gait
• Prominent (conspicuous) forehead (frontal bossing)
• Disproportionately large head-to-body size difference
• Hypotonia
• Polyhydramnios
• Bowed legs
• Spinal stenosis

Treatment of Achondroplasia

There is no treatment for Achondroplasia but life expectancy, intelect and sexual development are generally normal. The most serious complication of achondroplasia is the narrowing of the spinal canal called "spinal stenosis." The canal houses the spinal cord and such narrowing can lead to a compression of the cord and severe neurological problems. Patients with achondroplasia have a short stature, a long trunk, and shortened limbs which are noticeable at birth. Adults usually reach a height of between 42 and 56 inches. Surgical decompression of the cord is needed to relieve the pressure on it. This is done by opening the canal at the affected levels in a procedure called a "laminectomy." Related abnormalities, including spinal stenosis and spinal cord compression, should be treated when they cause problems.