A deformity, dysmorphism, or dysmorphic feature is a major abnormality of an organism that makes a part of the body appear or function differently than how it is supposed to.
Causes
Deformity can be caused by a variety of factors:
*
Arthritis
Arthritis is a general medical term used to describe a disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, Joint effusion, swelling, and decreased range of motion of ...
and other rheumatoid disorders
*Chronic application of external forces, e.g.
artificial cranial deformation
Artificial cranial deformation or modification, head flattening, or head binding is a form of body alteration in which the skull of a human being is deformed intentionally. It is done by distorting the normal growth of a child's skull by apply ...
*Chronic
paresis
In medicine, paresis (), compound word from Greek , (πᾰρᾰ- “beside” + ἵημι “let go, release”), is a condition typified by a weakness of voluntary movement, or by partial loss of voluntary movement or by impaired movement. Whe ...
,
paralysis
Paralysis (: paralyses; also known as plegia) is a loss of Motor skill, motor function in one or more Skeletal muscle, muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory d ...
or
muscle imbalance, especially in children, e.g. due to
poliomyelitis
Poliomyelitis ( ), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe ...
or
cerebral palsy
Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, spasticity, stiff muscles, Paresis, weak muscles, and tremors. There may b ...
*Complications at
birth
Birth is the act or process of bearing or bringing forth offspring, also referred to in technical contexts as parturition. In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the f ...
*Damage to the
fetus
A fetus or foetus (; : fetuses, foetuses, rarely feti or foeti) is the unborn offspring of a viviparous animal that develops from an embryo. Following the embryonic development, embryonic stage, the fetal stage of development takes place. Pren ...
or
uterus
The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the hollow organ, organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic development, embryonic and prenatal development, f ...
*Fractured bones left to heal without being properly
set
Set, The Set, SET or SETS may refer to:
Science, technology, and mathematics Mathematics
*Set (mathematics), a collection of elements
*Category of sets, the category whose objects and morphisms are sets and total functions, respectively
Electro ...
(
malunion
A malunion is when a fractured bone does not heal properly. Some ways that it shows is by having the bone being twisted, shorter, or bent. Malunions can occur by having the bones improperly aligned when immobilized, having the cast taken off t ...
)
*Genetic
mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, ...
*Growth or hormone disorders
*
Skin disorders
*Reconstructive surgery following a severe injury, e.g.
burn injury
Deformity can occur in all organisms:
*
Frogs
A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough skin texture due to ...
can be mutated due to ''
Ribeiroia'' (
Trematoda
Trematoda is a class of flatworms known as trematodes, and commonly as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is a mol ...
) infection.
*
Plants
Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars f ...
can undergo irreversible
cell deformation
*
Insects
Insects (from Latin ') are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed ...
, such as
honeybees
A honey bee (also spelled honeybee) is a eusocial flying insect within the genus ''Apis'' of the bee clade, all native to mainland Afro-Eurasia. After bees spread naturally throughout Africa and Eurasia, humans became responsible for the cur ...
, can be affected by
deformed wing virus
*
Fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
can be found with
scoliosis
Scoliosis (: scolioses) is a condition in which a person's Vertebral column, spine has an irregular curve in the coronal plane. The curve is usually S- or C-shaped over three dimensions. In some, the degree of curve is stable, while in others ...
due to environmental factors
Mortality

In many cases where a major deformity is present at birth, it is the result of an underlying condition severe enough that the baby does not survive very long. The mortality of severely deformed births may be due to a range of complications including missing or non-functioning vital organs, structural defects that prevent necessary function, high susceptibility to injuries, abnormal facial appearance, or infections that eventually lead to death.
In some cases, such as that of
twins
Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of Twin Last Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two e ...
, one fetus is brought to term healthy, while the other faces major, even life-threatening defects. An example of this is seen in cattle, referred to as
amorphous globosus.
In mythology
There are many instances of
mythological
Myth is a genre of folklore consisting primarily of narratives that play a fundamental role in a society. For scholars, this is very different from the vernacular usage of the term "myth" that refers to a belief that is not true. Instead, the ...
characters showing signs of a deformity.
* Descriptions of
mermaids
In folklore, a mermaid is an aquatic creature with the head and upper body of a female human and the tail of a fish. Mermaids appear in the folklore of many cultures worldwide, including Europe, Latin America, Asia, and Africa.
Mermaids are ...
may be related to the symptoms of
sirenomelia.
* The
Irish mythology
Irish mythology is the body of myths indigenous to the island of Ireland. It was originally Oral tradition, passed down orally in the Prehistoric Ireland, prehistoric era. In the History of Ireland (795–1169), early medieval era, myths were ...
includes the
Fomorians
The Fomorians or Fomori (, Modern ) are a supernatural race in Irish mythology, who are often portrayed as hostile and monstrous beings. Originally they were said to come from under the sea or the earth. Later, they were portrayed as sea raider ...
, who are almost without exception described as being deformed, possessing only one of what most have two (
eyes
An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system.
In higher organisms, the ey ...
,
arms
Arms or ARMS may refer to:
*Arm or arms, the upper limbs of the body
Arm, Arms, or ARMS may also refer to:
People
* Ida A. T. Arms (1856–1931), American missionary-educator, temperance leader
Coat of arms or weapons
*Armaments or weapons
**Fi ...
,
legs, etc.) or having larger than normal limbs.
*
Hephaestus
Hephaestus ( , ; wikt:Hephaestus#Alternative forms, eight spellings; ) is the Greek god of artisans, blacksmiths, carpenters, craftsmen, fire, metallurgy, metalworking, sculpture and volcanoes.Walter Burkert, ''Greek Religion'' 1985: III.2. ...
, of
Greek Mythology
Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of ancient Greek folklore, today absorbed alongside Roman mythology into the broader designation of classical mythology. These stories conc ...
, was born with a
club foot
Clubfoot is a congenital or acquired defect where one or both feet are supinated, rotated inward and plantar flexion, downward. Congenital clubfoot is the most common congenital malformation of the foot with an incidence of 1 per 1000 births. ...
.
See also
*
Birth defect
A birth defect is an abnormal condition that is present at birth, regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth de ...
*
Body dysmorphic disorder
Body dysmorphic disorder (BDD), also known in some contexts as dysmorphophobia, is a mental disorder defined by an overwhelming preoccupation with a perceived flaw in one's physical appearance. In BDD's delusional variant, the flaw is imagined ...
*
Congenital abnormality
*
Disfigurement
Disfigurement is the state of having one's appearance deeply and persistently harmed medically, such as from a disease, birth defect, or wound. General societal attitudes towards disfigurement have varied greatly across cultures and over time ...
*
Genetic variation
Genetic variation is the difference in DNA among individuals or the differences between populations among the same species. The multiple sources of genetic variation include mutation and genetic recombination. Mutations are the ultimate sources ...
*
Malformation
A birth defect is an abnormal condition that is present at birth, regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth de ...
*
Monstrous birth
*
Phocomelia
*
Polymelia
*
Teratology
Teratology is the study of abnormalities of physiological development in organisms during their life span. It is a sub-discipline in medical genetics which focuses on the classification of congenital abnormalities in dysmorphology caused by ...
References
Further reading
*
{{Authority control
Human appearance
Anatomy
Developmental biology