Dysmelia (from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

(), "bad" + (), "limb" + English suffix -ia) is a

congenital disorder A birth defect is an abnormal condition that is present at childbirth, birth, regardless of its cause. Birth defects may result in disability, disabilities that may be physical disability, physical, intellectual disability, intellectual, or dev ...

of a limb resulting from a disturbance in

embryonic development In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm, sperm cell (spermat ...

Types

Dysmelia can refer to * missing ( aplasia) limbs: amelia (including tetraamelia), oligodactyly, congenital amputation e.g. tibial or

radial aplasia Radial aplasia is a congenital defect which affects the formation of the radius bone in the arm. The radius is the lateral bone (thumb side) which connects the humerus of the upper arm to the wrist via articulation with the carpal bones. A child ...

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 ...

of limbs: shortening (micromelia,

rhizomelia Rhizomelia refers to either a disproportion of the length of the proximal limb, such as the shortened limbs of achondroplasia, or some other disorder of the hip or shoulder. According to Stedman's medical dictionary "rhizomelic" means "relating to ...

or mesomelia),

ectrodactyly Ectrodactyly, split hand, or cleft hand () involves the deficiency or absence of one or more central Digit (anatomy), digits of the hand or foot and is also known as split hand/split foot malformation (SHFM). The hands and feet of people with ec ...

, phocomelia, meromelia,

syndactyly Syndactyly is a condition wherein two or more digits are fused together. It occurs normally in some mammals, but is an unusual condition in humans. The term is . Classification Syndactyly can be simple or complex. * In simple syndactyly, adja ...

, brachydactyly,

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. ...

* extra limbs: polymelia,

polydactyly Polydactyly is a birth defect that results in extra fingers or toes. The hands are more commonly involved than the feet. Extra fingers may be painful, affect self-esteem, or result in clumsiness. It is associated with at least 39 genetic mut ...

, polysyndactyly * others: hemimelia, symbrachydactyly Polydactyly ECS

Occurrence rate

Birth defects involving limbs occur in 0.69 per 1000.

Causes

Dysmelia can be caused by *

Inheritance Inheritance is the practice of receiving private property, titles, debts, entitlements, privileges, rights, and obligations upon the death of an individual. The rules of inheritance differ among societies and have changed over time. Offi ...

of abnormal

genes In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

, e.g.

or brachydactyly, symptoms of deformed limbs then often occur in combination with other symptoms (

syndrome A syndrome is a set of medical signs and symptoms which are correlated with each other and often associated with a particular disease or disorder. The word derives from the Greek language, Greek σύνδρομον, meaning "concurrence". When a sy ...

s) * external causes during pregnancy (thus not inherited), e.g. via

amniotic band syndrome Constriction ring syndrome (CRS) is a congenital disorder with unknown cause. Because of the unknown cause there are many different, and sometimes incorrect, names. It is a malformation due to intrauterine bands or rings that produce deep grooves ...

teratogenic 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 ...

drugs (e.g.

thalidomide Thalidomide, sold under the brand names Contergan and Thalomid among others, is an oral administered medication used to treat a number of cancers (e.g., multiple myeloma), graft-versus-host disease, and many skin disorders (e.g., complication ...

, which causes phocomelia) or environmental chemicals * ionizing radiation (

nuclear weapon A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission or atomic bomb) or a combination of fission and fusion reactions (thermonuclear weapon), producing a nuclear exp ...

radioiodine There are 40 known isotopes of iodine (53I) from 108I to 147I; all undergo radioactive decay except 127I, which is stable. Iodine is thus a monoisotopic element. Its longest-lived radioactive isotope, 129I, has a half-life of 16.14 million ye ...

radiation therapy Radiation therapy or radiotherapy (RT, RTx, or XRT) is a therapy, treatment using ionizing radiation, generally provided as part of treatment of cancer, cancer therapy to either kill or control the growth of malignancy, malignant cell (biology), ...

) * infections * metabolic imbalance

Syndromes with dysmelia

* 2p15-16.1 microdeletion syndrome * Achard syndrome * Ackerman syndrome * Acrocallosal syndrome * Acropectoral syndrome * Adams–Oliver syndrome * Aglossia adactylia *

Amniotic band syndrome Constriction ring syndrome (CRS) is a congenital disorder with unknown cause. Because of the unknown cause there are many different, and sometimes incorrect, names. It is a malformation due to intrauterine bands or rings that produce deep grooves ...

Apert syndrome Apert syndrome is a form of acrocephalosyndactyly, a congenital disorder characterized by malformations of the skull, face, hands and feet. It is classified as a branchial arch syndrome, affecting the first Pharyngeal arch, branchial (or pharyn ...

* Autosomal recessive Robinow syndrome * Basel–Vanagaite–Sirota syndrome ( Microlissencephaly- Micromelia syndrome) * Campomelic dysplasia * Cardiofaciocutaneous syndrome * Catel–Manzke syndrome * Cenani–Lenz syndrome * Corneodermatoosseous syndrome * Diploid triploid mosaic * Ectrodactyly–ectodermal dysplasia–cleft syndrome *

Edwards syndrome Edwards may refer to: People * Edwards (surname), an English surname * Edwards family, a prominent family from Chile * Edwards Barham (1937–2014), American politician * Edwards Davis (1873–1936), American actor, producer, and playwright * Edwa ...

* Ellis–Van Creveld syndrome * Fibular dimelia diplopodia syndrome (Leg duplication mirror foot syndrome) *

Greig cephalopolysyndactyly syndrome Greig cephalopolysyndactyly syndrome is a disorder that affects development of the limbs, head, and face. The features of this syndrome are highly variable, ranging from very mild to severe. People with this condition typically have one or more ...

* Haas syndrome * Hanhart syndrome *

Holt–Oram syndrome Holt–Oram syndrome (also called atrio-digital syndrome, atriodigital dysplasia, cardiac-limb syndrome, heart-hand syndrome type 1, HOS, ventriculo-radial syndrome) is an autosomal dominant disorder that affects bones in the arms and hands (th ...

* Humeroradial synostosis * Johnson–Munson syndrome *

Joubert syndrome Joubert syndrome is a rare autosomal recessive genetic disorder that affects the cerebellum, an area of the Human brain, brain that controls balance and coordination. Joubert syndrome is one of the many genetic syndromes associated with syndromic ...

McKusick–Kaufman syndrome McKusick–Kaufman syndrome (MKS) is a rare genetic condition caused by mutations in the '' MKKS'' gene, which affect how cells develop and function. It is named after Dr. Robert L. Kaufman and Victor McKusick, who studied the condition and helped ...

* Mermaid syndrome * Mesomelia-Synostoses syndrome (8q13 microdeletion syndrome) * Microgastria * Myhre syndrome * Nager acrofacial dysostosis * Neu–Laxova syndrome *

Patau syndrome Patau syndrome is a syndrome caused by a chromosomal abnormality, in which some or all of the cells of the body contain extra genetic material from chromosome 13. The extra genetic material disrupts normal development, causing multiple and co ...

Pfeiffer syndrome Pfeiffer syndrome is a rare genetic disorder, characterized by the premature fusion of certain bones of the human skull, skull (craniosynostosis), which affects the shape of the head and face. The syndrome includes abnormalities of the hands an ...

* Poland syndrome *

Radial aplasia Radial aplasia is a congenital defect which affects the formation of the radius bone in the arm. The radius is the lateral bone (thumb side) which connects the humerus of the upper arm to the wrist via articulation with the carpal bones. A child ...

* Roberts SC-Phocomelia syndrome (Phocomelia syndrome) * Rubinstein–Taybi syndrome * Silver–Russell syndrome * Split-hand split-foot malformation (SHFM) * TAR syndrome (thrombocytopenia with absent radius) * Tetra-amelia syndrome * Ulbright–Hodes syndrome * VACTERL association * Wallis–Zieff–Goldblatt syndrome

References

External links

DysNet: An organisation for people affected by Dysmelia (congenital limb difference)

Reach: Association for Children with Upper Limb Deficiency)
{{Congenital malformations and deformations of musculoskeletal system Congenital disorders of musculoskeletal system Supernumerary body parts