Dwarfism

Dwarfism
Specialty	Medical genetics

Dwarfism (pronounced dwo[ʀ]fiz'm /ˈdwɔːˌfɪzɪm/) is a medical term describing a person of short stature, with the most widely accepted definition of a dwarf being a person with an adult height of less than 4 feet 10 inches (147cm). ^[1] Dwarfism can be caused by over 200 separate medical conditions, and as such the symptoms of individual dwarfs can vary greatly. People who are affected by dwarfism are often referred to as "little people."^[2]

Characteristics of dwarfism vary greatly in individuals. Disproportionate dwarfism is identified by one or more body parts being disproportionately large or small compared to the rest of the body, with growth abnormalities in specific areas being apparent. In cases of proportionate dwarfism the body parts are proportional to each other with a general lack of growth being apparent. Hypotonia, or a lack of muscle, is common in dwarfs, but intelligence and life span are usually normal.

The most common cause of dwarfism is achondroplasia, a bone growth disorder responsible for 70% of dwarfism cases.^[1] In cases of achondroplasia the limbs are disproportionally short compared to the trunk (abdomen area), with the head being larger than normal and unique facial features being present. Conditions in humans characterized by disproportional body parts are typically caused by one or more genetic disorders in bone or cartilage development. Forms of extreme shortness in humans characterized by proportional body parts usually have a hormonal cause such as growth hormone deficiency, once known as "pituitary dwarfism".^[2][3]

There is no universal treatment for dwarfism. Individual abnormalities such as bone growth disorders can sometimes be treated through surgery, and some hormone disorders can be treated through medication, but in most cases it is impossible to treat all of the symptoms of dwarfism. Most of the time lifestyle remedies are needed in order to cope with the effects of dwarfism. In-home devices like specialized furniture is often needed to help people who have dwarfism function normally.^[4] Many support groups also exist in order to help sufferers of dwarfism cope with the challenges they face and to help them function independently.^[5]

Dwarfism is a highly visible condition that can often carry negative connotations in society. Some believe that people afflicted with dwarfism are intellectually challenged or have personality disorders. Due to their unusual height, people with dwarfism are often used as spectacles in entertainment or portrayed with derogatory stereotypes. In popular culture dwarfs are often portrayed in roles directly related to their abnormal height. Heightism is a serious problem that can lead to ridicule as a child and discrimination as an an adult for a person with dwarfism.^[6][7]

Dwarfism is a medical disorder with the sole requirement being an adult height of under 4 feet 10 inches (147cm). It is almost always classified in regards to the underlying condition that is the cause for the short stature. Dwarfism does not necessarily have to be caused by a disease or genetic disorder, it could simply be a naturally occurring part of a person's genetics. If dwarfism is caused by a medical disorder, the person is diagnosed and referred to by the underlying disorder.

Disorders that cause dwarfism may be classified according to one of hundreds of names, which are usually permutations of the following roots:

• rhizomelic = root, e.g. bones of upper arm or thigh
• mesomelic = middle, e.g. bones of forearm or lower leg
• acromelic = end, e.g. bones of hands and feet.
• micromelic = entire limb shortened
• chondro = of cartilage
• osteo = of bone
• spondylo = of the vertebrae
• plasia = form
• trophy = growth

Examples include achondroplasia, osseous dysplasia, chondrodystrophy, and osteochondrodystrophy.^[8]

The universal defining characteristic of dwarfism is an adult height of less than 4 feet 10 inches. Since those afflicted with dwarfism have such a wide range of physical characteristics, oddities in individuals are understood by diagnosing and observing the underlying disorders.

Disproportionate dwarfism is characterized by one or more body parts being disproportionately large or small compared to the rest of the body. In achondroplasia the trunk is normally sized with the limbs being disproportionately short, the head being larger than usual, and the forehead being prominent.^[3] Facial features are often affected and individual body parts may have problems associated with them. Orthopedic problems can arise across multiple conditions such as diastrophic dysplasia and pseudoachondroplasia.

Proportionate dwarfism is marked by body parts being proportional but stunted.^[9] Height is significantly below average and there may be long periods without any significant growth. Sexual development is often delayed or impaired into adulthood. Unlike disproportionate dwarfism, mental capacity may be diminished in some cases of proportionate dwarfism. The overall stunted growth can lead to impaired intelligence when compared to the physical age.

Physical maleffects of malformed bones vary according to the specific disease. Many involve pain resulting from joint damage from abnormal bone alignment, or from nerve compression (e.g, spinal stenosis).^[2]. Early degenerative joint disease, exaggerated lordosis or scoliosis, and constriction of spinal cord or nerve roots can cause pain and disability.^[10] Reduced thoracic size can restrict lung growth and reduce pulmonary function. Some forms of dwarfism are associated with disordered function of other organs, such as the brain or liver, sometimes severely enough to be more disabling than the abnormal bone growth.^[11] As well, many dwarfs are given injections of Human Growth Hormone during their early years, but the HGH injections may cause adverse effects on the cardiac muscles, making them too large or thick to properly function, causing death through cardiac failure in the patient.^[12]

Mental effects also vary according to the specific underlying syndrome. In most cases of skeletal dysplasia, such as achondroplasia, mental function is not impaired in any way. However, there are syndromes which can affect the cranial structure and growth of the brain, severely impairing mental capacity. Growth disorders can stunt the growth of the brain in addition to the body resulting in mental impairment as well. Unless the brain is directly affected by the underlying disorder, there is little to no chance of mental impairment that can be attributed to dwarfism.

Dwarfism can result from a myriad of different medical conditions, each with their own separate symptoms and causes. The most recognizable and most common form of dwarfism is achondroplasia, which accounts for 70% of dwarfism cases and produces rhizomelic short limbs, increased spinal curvature, and distortion of skull growth. Achondroplasia is an autosomal dominant disorder caused by a faulty allele being present in a person's genome. If a pair of achondroplasia alleles are present, the result is fatal. Achondroplasia is a mutation in the fibroblast growth factor receptor gene 3 (FGFR3), which is an inhibitor that regulates bone growth. In cases of achondroplasia, the FGR3 gene is too aggressive, negatively impacting bone growth. ^[13]

Other relatively common types include spondyloepiphyseal dysplasia congenita (SED), diastrophic dysplasia, pseudoachondroplasia, hypochondroplasia, and osteogenesis imperfecta (OI). Severe shortness with skeletal distortion also occurs in several of the mucopolysaccharidoses and other storage.

Dwarfism is often diagnosed in childhood due to the visible nature of the condition. A physical examination can usually diagnose a type of dwarfism, but genetic testing and diagnostic imaging may be used to deduce the exact condition present. ^[14] In a person's youth, growth charts that track height can be used to diagnose subtle forms of dwarfism that have no striking physical characteristics.

Short stature or stunted growth as a youth is usually what brings the condition to medical attention. Skeletal dysplasia is usually suspected because of obvious physical features (e.g., unusual configuration of face or shape of skull), because of an obviously affected parent, or because body measurements (arm span, upper to lower segment ratio) indicate disproportion. Bone x-rays are often the key to diagnosis of a specific skeletal dysplasia, but they are not the sole tool to identify dysplasias. Most children with suspected skeletal dysplasias will be referred to a genetics clinic for diagnostic confirmation and genetic counseling. In the last decade, genetic tests for some of the specific disorders have become available.^[15]

During the initial medical evaluation for shortness, the absence of disproportion and the other clues above usually indicates other causes than bone dysplasias. Extreme shortness with completely normal proportions sometimes indicates growth hormone deficiency (pituitary dwarfism).^[16]

Short stature alone, in the absence of any other abnormalities, may be the result of the distribution of offspring height from short-statured parents, rather than a symptom of any medical condition.^[17]

Traditionally ambiguous, the appropriate term for describing a person of particularly short stature (or specifically with the genetic condition achondroplasia) has developed euphemistically over the past few centuries.

"Midget," whose etymology indicates a "small sandfly,"^[18] came into prominence in the mid-1800s after Harriet Beecher Stowe used it in her novels Sunny Memories of Foreign Lands and Oldtown Folks where she described children and an extremely short man, respectively.^[19] Later, the word was deemed highly offensive because it was the term used to describe P.T. Barnum's dwarfs used for public amusement during the freak show era. ^[2] It is also not considered accurate as it is not a medical diagnosis, though it is sometimes used to describe those who are particularly short but still proportional.^[20]

The term "dwarf" became used to describe those with achondroplasia first notably by the Brothers Grimm in their famous fairy tale Little Snow White, ^[21] although it was used in Jonathan Swift's Gulliver's Travels to describe a giant who was only 20ft tall compared to his 40ft peers.^[22] Dwarf too has been condemned as inaccurate and insensitive because of its mystical and fairy tale history.^[2]

The LPA (Little Peoples of America) deems "little people" the most appropriate description.^[2]

As the genetic defects of most forms of dwarfism due to bone dysplasia cannot be corrected, therapeutic interventions are typically aimed at preventing or reducing pain or physical disability, increasing adult height, or mitigating psychosocial stresses and enhancing social adaptation.^[5]

Forms of dwarfism associated with the endocrine system may be treated through hormonal therapy. If the cause is prepubescent hyposecretion of growth hormone, supplemental growth hormone may correct the abnormality. If the receptor for growth hormone itself has been affected then the condition may be harder to treat. Hypothyroidism is another possible cause of dwarfism that can be treated through hormonal therapy. Injections of thyroid hormone can mitigate the effects of the condition, but physical complications may be permanent.

Pain and disability may be ameliorated by physical therapy, by braces or other orthotic devices, or by surgical procedures.^[5] The only simple interventions that increase perceived adult height are dress enhancements such as shoe lifts or hairstyle. Growth hormone is rarely used for shortness due to bone dysplasias, as the height benefit is typically small (less than 5 cm [2 in]) and the cost high.^[4] The most effective means of increasing adult height by several inches is limb-lengthening surgery, though availability is limited and cost is high in terms of money, discomfort, and interruption of life. Most people with dwarfism do not avail themselves of this, and it remains controversial.^[2] For other types of dwarfism, surgical treatment is not possible.

When depicted in art, literature, or movies, dwarfs are rarely depicted as "regular people who are very short" but often as a species apart. Novelists, artists, and moviemakers attach special moral or aesthetic significance to the "apartness" or the misshapenness.

Artistic representations of dwarfism can be found on Greek vases and other ancient artefacts, including ancient Egyptian art. Documentation of dwarfs can also be found on European paintings and many pictures. Many European paintings (especially Spanish) of the 16th–19th centuries depict dwarfs by themselves or with others. In the Talmud, it is said that the second born son of the Egyptian Pharaoh of the Bible was a dwarf.^[23] Recent scholarship has indicated that the ancient Egyptians esteemed dwarfs. ^[24] Several important traditional mythological figures of the North American Wyandot nation are portrayed as dwarfs.^[25]

Several works of literature have treated dwarfism as a major theme, although not necessarily realistically:

• The Tin Drum (Die Blechtrommel) by Günter Grass. The protagonist, Oskar Matzerath, refuses to grow up and as such goes through many large events in history with the stature of a small child. ^[26]
• Stones from the River by Ursula Hegi. Trudi Montag is a dwarf who tries to survive in a small town during World War II.^[27]
• The Dwarf by Pär Lagerkvist. The entire novel is based around a dwarf protagonist and his life in an Italian city-state. ^[28]
• A Prayer for Owen Meany by John Irving. Owen Meany, the friend of the narrator and major focus of the story, is a dwarf with a fixed voicebox.^[29]
• Hop-Frog, or The Eight Chained Ourang-Outangs by Edgar Allan Poe. The titular character Hop-Frog and his friend Tripetta are both dwarfs. ^[30]
• A Song of Ice and Fire series by George R.R. Martin. One of the main characters, Tyrion Lannister, is a dwarf who struggles with acceptance by "normal" people. ^[31]
• Maybe the Moon, by Armistead Maupin, has as its protagonist Cadence Roth, a Jewish dwarf actress. The character was based on Maupin's friend Tamara De Treaux, who played the title role in the movie E.T.. ^[32]

The actor and stunt man Verne Troyer has become famous playing the character "Mini-Me" in two Austin Powers movies^[33]. Fellow stuntman Jason "Wee-Man" Acuña^[34] has also achieved fame as one of the Jackass cast-members.

In the mid-1970s, Sid and Marty Krofft built an indoor theme park in Atlanta, Georgia called The World of Sid and Marty Krofft. This had a live stage production that was at that time the largest gathering of "little people" since the filming of The Wizard of Oz in 1937-38 as well as being the largest indoor theme park built to that time. The facility that was built to house this theme park is today the studios of CNN, the Cable News Network, and CNN Headline News.^[35]

Actor Peter Dinklage played the lead role of Finbar McBride in the highly acclaimed 2003 film The Station Agent. The movie won Sundance Film Festival awards that year. (Best Drama, Audience Award; Best Screenplay, Tom McCarthy).

In the 1990s, Seinfeld featured a dwarf character, Mickey Abbott, in seven episodes; Mickey was played by actor Danny Woodburn. He got into several physical altercations with 6-foot (1.8 m)-plus Kramer. In one episode, he was ostracized by his dwarf peers for using lifts in his shoes to make him look taller.

The actor Warwick Davis has found success in several notable fantasy franchises, including Star Wars, Harry Potter, Willow, Leprechaun, Gulliver's Travels, The 10th Kingdom,The Hitchhiker's Guide to the Galaxy (film) and The Chronicles of Narnia (both the 1989 television serial and again in the 2008 film version of Prince Caspian).^[36] Actor Tony Cox has appered in several movies like Friday, Bad Santa, and Date Movie. Deep Roy is another fellow actor with dwarfism. Roy has acted in many movies such as Star Wars as an Ewok and in his most famous role, all of the Oompa Loompas in Charlie and the Chocolate Factory.^[37].

Since 2006, Dylan Postl has appeared on WWE programming as Hornswoggle, a wrestling leprechaun.

• Ellis-van Creveld syndrome
• List of people with dwarfism
• Primordial dwarfism
• Psychogenic dwarfism
• Gigantism
• Laron syndrome
• Mulibrey nanism
• Midget

Look up dwarf in Wiktionary, the free dictionary.

• Wheeless Textbook of Orthopedics online has general medical information about various disorders of cartilage and bone formation
• Little People of America
• Restricted Growth Association UK
• Little People: A Father Reflects on His Daughter's Dwarfism — and What It Means to Be Different, by Dan Kennedy. Critically acclaimed book in a free online edition.