Rare genetic disorder, achondroplasia affects the growth of bones in the arms and legs. Achondroplasia causes short stature and disproportionate dwarfism, with the upper limbs being shorter than the lower ones. With proper care and support, people with achondroplasia can live full and healthy lives.
Mutations in the FGFR3 gene, which produces a protein involved in the development and maintenance of bones and brain tissue, cause achondroplasia. During fetal development, this protein converts cartilage into bone. However, in people with achondroplasia, the protein is overactive or defective, resulting in abnormal bone growth.
Approximately 80% of cases of achondroplasia result from mutations occurring spontaneously (de novo) in the affected person's cells. This means that their family does not have a history of achondroplasia. Achondroplasia is inherited from one parent in 20% of cases (autosomal dominant inheritance). There is a 25% chance that a child born to two achondroplasia parents will inherit two copies of the mutated gene (homozygous achondroplasia), which results in severe dwarfism and often premature death.
People with achondroplasia usually have normal intelligence levels and do not have any mental or behavioral problems. However, they may experience physical symptoms such as:
Short stature that is significantly below average for age and sex
Short arms and legs, especially the upper arms and thighs
Short fingers with an inward curvature
A large head relative to body size
A prominent forehead
A small chin
A flat nose
A narrow chest
A low back curvature (scoliosis)
Bowing of the legs (leg length discrepancy)
Excessive inward curvature of the lower back (spondylolisthesis)
Weak muscle tone (hypotonia) that may affect motor skills development
Frequent ear infections due to blocked ear canals or enlarged eustachian tubes
Snoring due to enlarged tonsils or adenoids
Sleep apnea due to enlarged tonsils or adenoids blocking the airway during sleep
Hydrocephalus due to excess fluid around the brain
Crowded teeth due to limited space for them to grow properly
Spinal stenosis due to pressure on the spinal cord from bone growth
In some cases, achondroplasia can be detected before birth through prenatal testing methods, such as ultrasound or genetic testing on amniotic fluid or blood samples.
In addition to a physical examination and medical history, chondroplasia can also be diagnosed after birth by using X-rays or other imaging techniques to measure the length of an infant's bones. A doctor will also look for signs of complications like ear infections, sleep apnea, hydrocephalus, spinal stenosis, or scoliosis.
Achondroplasia is not a condition that requires a cure or treatment. However, some people with achondroplasia may require treatment to help manage complications of the condition.
Some common treatments for achondroplasia include:
An injection of synthetic growth hormone is used as a growth hormone therapy to promote growth and development in the body. Some people with achondroplasia may benefit from growth hormone therapy to improve bone density, muscle strength, and height, but there are also potential side effects like diabetes, cancer, and joint problems that may occur.
For some people with achondroplasia, surgery may be necessary to correct deformities or complications like leg bowing, spinal curvature, or breathing difficulties. In surgery, vertebrae may be fused (spinal fusion), bones can be lengthened (osteotomy), or excess tissue removed (tracheostomy).
Achondroplasia patients may benefit from physical therapy by improving mobility, flexibility, and posture. Physical therapy may also help prevent or reduce pain, stiffness, and muscle weakness.
The aim of occupational therapy is to help people with achondroplasia perform daily tasks such as dressing, eating, writing, and working by using activities and devices. People with achondroplasia may benefit from occupational therapy to improve their independence, self-esteem, and quality of life.
Using exercises and techniques to improve speech and language skills may improve communication, social interaction, and cognitive development in people with achondroplasia.
People with achondroplasia may have dental problems such as tooth decay, gum disease, or malocclusion (misalignment of the teeth). Dental care includes regular check-ups, cleaning, fluoride treatment, braces, or surgery.
There is no sure way to prevent achondroplasia from occurring. However, some factors that may reduce the risk of having a child with achondroplasia include:
An achondroplasia genetic counselor can assist parents in making informed decisions about whether or not to undergo prenatal testing. Genetic counseling can help parents make informed decisions about whether or not to undergo prenatal testing.
An achondroplasia screening test can detect certain features of the condition before birth, such as hydrocephalus (excess fluid around the brain) or facial asymmetry. Achondroplasia screenings can help identify babies with a higher chance of having a child and who may benefit from early intervention.
For babies diagnosed with achondroplasia before they turn one year old, early intervention involves providing specialized care and support. It is possible to improve their physical development, cognitive skills, emotional well-being, and social adjustment with early intervention.
Known as achondroplasia, it causes short stature and disproportionate dwarfism in the arms and legs due to abnormal cartilage development and bone formation. Mutated copies of the FGFR3 gene, which encodes instructions for making a bone growth protein, are the cause of achondroplasia inherited from one or both parents.
It is common for people with achondroplasia to have normal intelligence levels and physical appearance, but they may also experience some health problems as a result of their bone growth disorder, such as short limbs. Additionally, they may develop joint and spinal abnormalities, sleep apnea, and heart issues. As part of treatment for achondroplasia, physical therapy and orthopedic care are provided.
