Efforts to treat or prevent complications such as obesity, hydrocephalus, obstructive sleep apnea, middle ear infections or spinal stenosis may be required. Achondroplasia is the most common cause of dwarfism and affects about 1 in 27,500 people. Signs and symptoms
Disproportionate dwarfism
Shortening of the proximal limbs (called rhizomelic shortening)
Short fingers and toes, with "trident hands" (short hands with stubby fingers, and a separation between the middle and ring fingers – reminiscent of a trident on fetal ultrasound )
Large head with prominent forehead frontal bossing
Small midface with a flattened nasal bridge
Spinal kyphosis (convex curvature) or lordosis (concave curvature)
Varus (bowleg) or valgus (knock knee) deformities
Frequent ear infections (due to Eustachian tube blockages), sleep apnea (which can be central or obstructive), and hydrocephalus

Complications
Children
Children with achondroplasia often have less muscle tone; because of this it is common for them to have delayed walking and motor skills. It is also common for children to have bowed legs, scoliosis, lordosis, arthritis, issues with joint flexibility, breathing problems, ear infections, and crowded teeth. These issues can be treated with surgery, braces, or physical therapy. Hydrocephalus is a severe effect associated with achondroplasia in children. This condition occurs when cerebrospinal fluid is not able to flow in and out of the skull because of how the spine narrows. This fluid build up is associated with an enlarged head, vomiting, lethargy, headaches, and irritability. A shunt surgery is commonly performed to treat this condition, but an endoscopic third ventriculostomy can also be done. Adults
Adults with achondroplasia often face issues with obesity and sleep apnea.
The diagnosis can be made by fetal ultrasound by progressive discordance between the short femur length and biparietal diameter by age. The trident hand configuration can be seen if the fingers are fully extended.Another common characteristic of the syndrome is thoracolumbar gibbus in infancy. Treatment
There is no known cure for achondroplasia even though the cause of the mutation in the growth factor receptor has been found. Although used by those without achondroplasia to aid in growth, human growth hormone does not help people with achondroplasia, which involve a different hormonal pathway. Usually, the best results appear within the first and second year of therapy. After the second year of growth hormone therapy, beneficial bone growth decreases, so the therapy is not a satisfactory long-term treatment. As of December 2020, the treatment of achondroplasia with human growth hormone was approved only in Japan.An experimental drug called vosoritide has shown promise in stage 3 human trials, although its long-term effects are unknown.Limb-lengthening will increase the length of the legs and arms of someone with achondroplasia,  but little medical consensus exists regarding this practice. The age of surgery can vary from early childhood to adulthood.Research has also shown that introducing parents of children with achondroplasia to support and advocacy groups at the time of diagnosis can improve outcomes. Several patient advocacy groups exist to support people with achondroplasia and their families. Epidemiology
Achondroplasia is one of several congenital conditions with similar presentations, such as osteogenesis imperfecta, multiple epiphyseal dysplasia tarda, achondrogenesis, osteopetrosis, and thanatophoric dysplasia.