Achondroplasia In Children: Causes And Characteristics

Achondroplasia in children is one of the most common forms of dwarfism. For every 25,000th child born, one of them has a genetic bone disorder.

According to studies,  we know that 75% of cases of achondroplasia in children are due to new genetic mutations during fetal development,  while the remaining 25% are related to inherited genes. This genetic mutation is responsible for 70% of cases of dwarfism.

Achondroplasia in children is classified as a form of disproportionate dwarfism. The condition affects the development of the long bones, while the development of the spine is normal. This leads to disproportionate growth.

Achondroplasia in children occurs due to a change in the cellular DNA. This change affects the receptors for growth factor 3 present in fibroblasts. This leads to an anomaly in the formation of cartilage, and later it blocks the normal bone growth.

There is an increased risk of death in childhood, due to the compression of the medulla, and there may also be an obstruction in the respiratory system.

Probability of achondroplasia

The probability that a child whose parents do not have this disorder will suffer from achondroplasia is 1/25000. This rate increases to 50% if one parent has the disorder and 75% if both parents have.

Furthermore, there is a 2.5% probability that a child will have homozygous achondroplasia if both parents have the disorder.

Signs of achondroplasia in children

Signs of achondroplasia can be assessed, based on a diagnosis during fetal development. It can be deduced from bone measurements,  but after birth it can be diagnosed with certainty.

Treatment for achondroplasia in children

There is no pharmacological treatment for achondroplasia. Despite the fact, they have been able to identify the gene that acts as the carrier of chromosome 4.P and 16.3, known  as the short branch of chromosome 4. 

Intellectual capacity and physical characteristics

Children with achondroplasia have a normal intellectual capacity. However, the physical characteristics are quickly identifiable. The average adult height for a person with this disorder is 1.20 meters.

The long bones, such as the femur and humerus,  are shorter compared to the forearm (radius and ulna) and the lower leg. The head is larger, compared to body size, with a large forehead and a flattened septum in the nose.

In some cases, there are dental problems, which involve clogged or twisted teeth. In general, the feet can be wider, with narrow toes and flat soles. Muscle tone is weak, which causes babies to develop more slowly in the beginning.

They may also have what is known as a three-forked hand, where there is more space between the middle finger and the ring finger. 

Associated disorders

In addition to the physical characteristics, children with achondroplasia can get associated diseases as they develop. However, as long as these are monitored, a child can lead a normal life and develop into an adult.

• Apnea:  when babies stop breathing for a few seconds.
• Ear Inflammation: Children with achondroplasia often suffer from repeated ear infections, which can lead to greater damage if left untreated.
• Compression of the spine:  this is a condition that occurs when the canal connecting the skull to the spine is very small. It compresses the spine and creates breathing problems.

• Hydrocephalus:  when fluid accumulates in the baby’s head, it can result in a rapid abnormal growth of the head. The size of the head should be closely monitored.
• Kyphosis:  this is a small hump that takes shape on the upper back. Generally, it occurs before the baby starts walking and it disappears later.
• Curve of the spine:  an inward curve at the lower back. This often occurs after the baby starts walking. It can be treated with special exercises.