Brachydactyly

Brachydactyly ( from Ancient Greek βραχύς brachys, short ' and δάκτυλος daktylos, finger' ) medically referred to the congenital malformation of the limbs ( dysmelia ) the Kurzfingrigkeit (common name ), a contraction of one or more fingers or toes.

The Kurzfingrigkeit is a dysmelia in the fingers and sometimes the metacarpal bones are reduced to varying degrees. In each family, different hereditary forms with very similar characteristics. Some forms of Kurzfingrigkeit are very rare. Most frequently found type A3 (only pinky affected) with a frequency in the different populations of between 3.4 % and 21 %. A special rate of 21% was observed in Japanese school children. Quite often, there is also type D ( only end member of the thumb affected) with a frequency in the different populations of between 0.41% and 4.0 %. Often reductions occur laterally symmetrical, sometimes missing entire phalanges. Using a special form of autosomal dominant inheritance in humans has been demonstrated. It is believed that the autosomal dominant mode of inheritance applies to all types of Kurzfingrigkeit.

We distinguish several types with various other features in the fingers or toes members, as well as isolated ( = sole ) appearance or in combination with malformations of other organs. Other malformations of fingers or toes are polydactyly, oligodactyly, syndactyly and polysyndactyly.

Overview of brachydactyly types

The various forms of brachydactyly can be classified according to the following scheme.

Brachydactyly type D as the most common form

As brachydactyly type D, the shortening of the last thumb member and the fingernail is called. This form of Kurzfingrigkeit occurs frequently on both sides, but also in many cases, occurs only on one side. In many cases, at the same time the big toe shortened. Brachydactyly type D occurs with a probability of 0.41 % to 4.0 % depending on the population. In male carriers of the genetic defect a reduced penetrance is observed (about 62% ).

Whether this form was already described the anomaly of the thumb in antiquity, is not known. In the literature it occurs relatively late. The name is probably brachydactyly 1896 Hector Louis François Leboucq back. The field of Brachyphalangie 1898 founded Pfitzner. Another name of the genetic defect is 1923 on JK Width cup back.

Other names are: Brachymegalodactylism ( Hefner 1924) and Ossificatio praecox hereditaria (O. Thomsen 1927). Heinrich Hoffmann ( Senior Physician at the Department of Dermatology Univ. Tübingen) referred to this anomaly as 1924 Hereditary piston thumb and 1928 as Brachyphalangie, although R. Pol in 1921 the name brachydactyly used.