<unk>  is a skeletal condition which exhibits a 'partial fusion or premature closing of the epiphysis with the distal phalanx of the thumb', according to Goodman et alia (1965). J.K. Breithenbecher (1923) found that distal phalanges of stub thumbs were one-half the length of full-length thumbs, while R.M. Stecher (1957) claimed that it is approximately two-thirds. The condition may either be unilateral (affecting one thumb) or bilateral (affecting both).
Brachydactyly type D
Cenani–Lenz syndactylism
Congenital contractural arachnodactyly
Ectrodactyly
Synpolydactyly
Camptodactyly
Acrocephalosyndactylia
Congenital clasped thumb