Thumb hypoplasia is a spectrum of congenital abnormalities of the thumb varying from small defects to complete absence of the thumb.[1] It can be isolated, when only the thumb is affected, and in 60% of the cases[2] it is associated with radial dysplasia[1] (or radial club, radius dysplasia, longitudinal radial deficiency). Radial dysplasia is the condition in which the forearm bone and the soft tissues on the thumb side are underdeveloped or absent.[3]
In an embryo the upper extremities develop from week four of the gestation.[1] During the fifth to eighth week the thumb will further develop.[4] In this period something goes wrong with the growth of the thumb but the exact cause of thumb hypoplasia is unknown.[1]
One out of every 100,000 live births shows thumb hypoplasia.[2] In more than 50% of the cases both hands are affected, otherwise mainly the right hand is affected.[1][2]
About 86% of the children with hypoplastic thumb have associated abnormalities.[1][2] Embryological hand development occurs simultaneously with growth and development of the cardiovascular, neurologic and hematopoietic systems.[2] Thumb hypoplasia has been described in 30 syndromes wherein those abnormalities have been seen. A syndrome is a combination of three or more abnormalities. Examples of syndromes with an hypoplastic thumb are Holt–Oram syndrome, VACTERL association[1] and thrombocytopenia absent radius (TAR syndrome).[2]
^ abcdefgRiley, S.A. & Burgess, R.C. (2009). Thumb Hypoplasia. Journal of Hand Surgery, vol 34A, 1564–1573
^ abcdefAshbaugh, H. & Gellman, H. (2009). Congenital Thumb Deformities and Associated Syndromes. Journal of Craniofacial Surgery, vol 20, number 4, 1039–1044
^Manske, P.R. & Goldfarb, C.A. (2009). Congenital Failure of Formation of the Upper Limb. Hand Clinics, 25, 157–170
^Hovius, S., Foucher, G. & Raimondi, P.L. (2002). The Pediatric Upper Limb. London: Informa Healthcare [ISBN missing][page needed]
Thumbhypoplasia is a spectrum of congenital abnormalities of the thumb varying from small defects to complete absence of the thumb. It can be isolated...
Hypoplasia (from Ancient Greek ὑπo- hypo- 'under' + πλάσις plasis 'formation'; adjective form hypoplastic) is underdevelopment or incomplete development...
complete absence of the radius, radial side of the carpal bones and thumb. Hypoplasia of the distal humerus may be present as well and can lead to stiffness...
autosomal dominant congenital disorder consisting of radial hypoplasia, triphalangeal thumbs, hypospadias, and maxillary diastema. It was first identified...
patient. There are a few slightly more common diagnoses such as pulmonary hypoplasia, cryptorchidism, congenital heart defects, tracheoesophageal fistulas...
brachyonychia, nail en raquette, and racquet thumb), the nail plate is flattened, the end of the thumb is widened and flattened, and the distal phalanx...
Dysplasia-Macular Dystrophy syndrome, Ectrodactyly-Fibular Aplasia/Hypoplasia (EFA) syndrome, and Ectrodactyly-Polydactyly. More than 50 syndromes and...
metacarpal fails to sit well 'on the saddle', for example because of hypoplasia, the first CMC joint tends to be subluxated (i.e. slightly displaced)...
Estermann, and Michael Rieger: Pollicization of the index finger in hypoplasia of the thumb. Experience with the method of Buck-Gramcko and retrospective analysis...
synostosis affecting the fourth and fifth metacarpals of a left hand with thumbhypoplasia type V. Specialty Medical genetics Causes Genetic mutation Frequency...
Radial hypoplasia is related to one form of polydactyly, sometimes called patty feet or hamburger feet by cat lovers to distinguish them from thumb cat polydactyls...
attached to shortened arms and legs Prenatal growth retardation Hypomelia (hypoplasia)- the incomplete development of a tissue or organ; less drastic than aplasia...
disorder which is characterized in the hands by bilateral nail hypoplasia on the thumb, index finger, and middle finger, absence of fingernails (anonychia)...
had started in 1983. Among the claimed birth defects are clubfoot, thumbhypoplasia, hip dysplasia, congenital heart defects, structural brain damage,...
seen among the same families included duplicated, underdeveloped thumb rays, hypoplasia of the thenar muscle, and syndactyly with metacarpal synostosis...
includes abnormalities of the hands and feet, such as wide and deviated thumbs and big toes. Pfeiffer syndrome is caused by mutations in the fibroblast...
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