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What is Poland syndrome and explain in detail?
Poland syndrome is a birth defect characterized by an underdeveloped chest muscle and short webbed fingers on one side of the body. There may also be short ribs, less fat, and breast and nipple abnormalities on the same side of the body. Typically, the right side is involved. Those affected generally have normal movement and health.The cause of Poland syndrome is unknown. One theory is that it is due to disruption of blood flow during embryonic development. It is generally not inherited from a persons parents, and no genes that contribute to the disorder have been identified. Diagnosis of Poland syndrome is based on its symptoms. Often, those with the syndrome remain undiagnosed, and some may not realize they have it until puberty.Treatment of Poland syndrome depends on its severity and may include surgical correction. The syndrome affects about 1 in 20,000 newborns, and males are affected twice as often as females. It is named after English surgeon Sir Alfred Poland, who described the condition when he was a student in 1841.

Signs and symptoms
A list of the common side effects broken down by frequency.Very frequent

Abnormal gastrointestinal tract
Absent pectoral muscles
Brachydactyly (Short fingers)
Dextrocardia
Diaphragmatic hernia/defect
Humerus absent/abnormal
Liver/biliary tract anomalies
Maternal diabetes
Oligodactyly/missing fingers
Radius absent/abnormal
Rhizomelic micromelia (relatively shorter proximal segment of the limbs compared to the middle and the distal segments)
Sparsity or abnormality of axillary hair on affected side
Syndactyly of fingers (webbing)
Ulna absent/abnormal
Upper limb asymmetry
Abnormal rib
Simian crease on affected sideFrequent

Hypoplastic/absent nipples
Scapula anomalyOccasional

Agenesis/hypoplasia of kidneys
Encephalocele/exencephaly
Abnormal morphology of hypothalamic-hypophyseal axis
Abnormal function of hypothalamic-hypophyseal axis
Microcephaly
Preaxial polydactyly
Ureteric anomalies (reflux/duplex system)
Vertebral segmentation anomalyIt is usually considered a unilateral condition. Some have claimed that the term can be applied in bilateral presentation, but others recommend using alternate terminology in those cases.

Causes
The cause of Poland syndrome is unknown. However, an interruption of the embryonic blood supply to the arteries that lie under the collarbone (subclavian arteries) at about the 46th day of embryonic development is the prevailing theory.The subclavian arteries normally supply blood to embryonic tissues that give rise to the chest wall and hand. Variations in the site and extent of the disruption may explain the range of signs and symptoms that occur in Poland syndrome. Abnormality of an embryonic structure called the apical ectodermal ridge, which helps direct early limb development, may also be involved in this disorder.

Diagnosis
Poland syndrome is usually diagnosed at birth, based upon the physical characteristics. Imaging techniques such as a CT scan may reveal the extent to which the muscles are affected. The syndrome varies in severity and as such is often not reported until puberty, when lopsided growth becomes apparent.

Treatment
Technique
The complete or partial absence of the pectoralis muscle is the malformation that defines Poland syndrome. It can be treated by inserting a custom implant designed by CAD (computer aided design). A 3D reconstruction of the patients chest is done using an implant shaped from a medical scan and designed to be perfectly adapted to the anatomy. The implant is made of medical grade silicone rubber. The treatment is purely cosmetic and does not restore the patients imbalanced upper body strength.The Poland syndrome malformations are morphological, so correction by custom implant is the first-line treatment. This technique allows a wide variety of patients to be treated with good outcomes. Poland Syndrome can be associated with bones, subcutaneous and mammary atrophy: the first, as for pectus excavatum, is successfully corrected by a custom implant, while the others can require surgical intervention such as lipofilling or silicone breast implant, in a second operation.

Surgery
The surgery takes place under general anaesthesia and lasts less than 1 hour. The surgeon prepares the locus to the size of the implant after performing an 8-centimetre (3.1 in) axillary incision, then inserts the implant beneath the skin. The closure is made in two planes.The implant replaces the pectoralis major muscle, thus enabling the thorax to be symmetrical and, in women, the breast as well. If necessary, especially in the case of women, a second operation will complement the result by the implantation of a breast implant and / or lipofilling.Lipomodelling is progressively used in the correction of breast and chest wall deformities. In Poland syndrome, this technique appears to be a major advance that will probably revolutionize the treatment of severe cases. This is mainly due to its ability to achieve previously unachievable quality of reconstruction with minimal scarring.

Epidemiology
Poland syndrome affects males three times as often as females and affects the right side of the body twice as often as the left. The incidence is estimated to range from one in 7,000 to one in 100,000 live births.

History
It was named in 1962 by Patrick Clarkson, a New Zealand-born British plastic surgeon working at Guys Hospital and Queen Marys Hospital, London. He noticed that three of his patients had both a hand deformity and an underdeveloped breast on the same side. He discussed this with his colleague at Guys Hospital, Dr Philip Evans, who agreed that the syndrome was "not widely appreciated". Clarkson found a reference to a similar deformity published by Alfred Poland, an English surgeon, over a hundred years earlier in Guys Hospital reports, in 1841