Acromesomelic Dysplasia

Achondroplasia is the most common disorder of short-limbed dwarfism. Affected individuals have arms and legs that are very short, while the torso is more nearly normal in size. During fetal development and childhood, cartilage? normally develops into bone, except in a few places, such as the nose and ears. In individuals with achondroplasia, something goes wrong during this process, especially in the long bones (such as those of the upper arms and thighs). The rate at which cartilage cells in the growth plates of the long bones turn into bone is slow, leading to short bones and reduced height. This syndrome is caused by specific mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Achondroplasia differs from AMD in that the upper bones of the arms and legs (the humerus and femur) are the most affected in achondroplasia, while it is the lower bones (radius and ulna in the arm, tibia, and fibula in the leg) and the hands and the feet that are the most affected in AMD. (For more information on this disorder, choose “ Achondroplasia ” as your search term in the Rare Disease Database.)

Acrodysostosis is an extremely rare disorder characterized by abnormally short, malformed bones of the hands and feet (peripheral dysostosis), abnormally short fingers and toes (brachydactyly), malformation, and shortening of the forearm bones (radius and ulna), and progressive growth retardation, resulting in short-limbed dwarfism. As children with the disorder grow older, they may experience progressively impaired and limited movements of the hands, feet, and/or elbows as well as pain? and swelling? in various joints (stiffness?, or reduced movement. সহজ বাংলা: জয়েন্টের প্রদাহ।" data-rx-term="arthritis" data-rx-definition="Arthritis means joint inflammation causing pain, swelling, stiffness, or reduced movement. সহজ বাংলা: জয়েন্টের প্রদাহ।">arthritis?) of the body. Affected individuals also exhibit characteristic malformations of the head and facial (craniofacial) area including an abnormally flat, underdeveloped (hypoplastic) “pug” nose, an underdeveloped upper jaw bone (maxillary hypoplasia), widely spaced eyes (ocular hypertelorism), and/or extra folds of skin that may partially cover the eyes’ inner corners (epicanthal folds). Intellectual disability may also be present. In most cases, acrodysostosis is thought to occur randomly, for unknown reasons (sporadic). (For more information on this disorder, choose “Acrodysostosis” as your search term in the Rare Disease Database.)

Acromicric dysplasia is another extremely rare inherited disorder characterized by abnormally short hands and feet, growth retardation, and delayed bone maturation leading to short-limbed dwarfism, and mild facial abnormalities. Craniofacial malformations may include an abnormally narrow opening between the upper and lower eyelids (palpebral fissures) and a short nose with upturned (anteverted) nostrils. In most cases, acromicric dysplasia appears to occur randomly, for unknown reasons (sporadically). However, autosomal dominant inheritance has not been ruled out. (For more information on this disorder, choose “Acromicric Dysplasia” as your search term in the Rare Disease Database.)

There are several syndromes of isolated shortening of the bones in the hands and feet, known as brachydactyly. Two of these syndromes, brachydactyly types A2 and C are also caused by mutations in the GDF5 gene.

Short stature may be the normal expression of genetic potential, in which case the growth rate is normal, or it may be the result of a condition causing growth failure with a lower-than-normal growth rate. Growth failure is the term that describes a growth rate below the appropriate growth velocity for age.

A child is considered short if he or she has a height that is below the fifth percentile; alternatively, some define short stature as a height less than 2 standard deviations below the mean, which is near the third percentile. Thus, 3-5% of all children are considered short. Many of these children have normal growth velocity. These short children include those with familial short stature or constitutional delay in growth and maturation. To maintain the same height percentile on the growth chart, growth velocity must be at least at the 25th percentile. When considering all children with short stature, only a few have a specific treatable diagnosis?, such as growth hormone deficiency or thyroid? gland makes too little hormone. সহজ বাংলা: থাইরয়েড হরমোন কম।" data-rx-term="hypothyroidism" data-rx-definition="Hypothyroidism means the thyroid gland makes too little hormone. সহজ বাংলা: থাইরয়েড হরমোন কম।">hypothyroidism?. Most of these are children with a slow growth velocity.

Symptoms