The number of phalanges and joints are key features of digit 'identity' and are central to limb functionality and evolutionary adaptation. Prior chick work indicated that digit phalanges and their associated joints arise in a different manner than the more sparsely jointed long bones, and their identity is regulated by differential signalling from adjacent interdigits. Currently, there is no ge...

Syndactyly type I is an autosomal dominant condition with complete or partial webbing between the third and fourth fingers or the second and third toes or both. We report here a previously undescribed phenotype of severe mesoaxial syndactyly and synostosis in patients born to affected parents. The characteristic features of these severe cases are (1) complete syndactyly and synostosis of the th...

This study is an analysis of the patterns of variation of the human hand, particularly the metric characters of palm, fingers and distal phalanges. Anthropometric measurements were performed on 146 Sardinian men and women, aged 21 to 31 years. The data were analyzed by inferential statistics (paired Student's t test, analysis of variance), and Principal Components Analysis. The results indicate...

Polydactyly is a common hereditary disorder in which extra or vestigial digits are present on the one or both sides of the extremities. It is ten times more frequent in Blacks than in Whites. Polydactyly occurs both in a sporadic form and in a hereditary form. In polydactyly type A, the extra digits contains phalanges, in polydactyly type B, there is no skeletal structure. The extra digit is ma...

The condition known as delta phalanx (or longitudinally bracketed epiphysis) is a rare congenital anomaly first described in 1964. The deformity consists of a triangular bone with an epiphysis running along the shortened side of the phalanx in a proximal to distal direction, making longitudinal growth of the digit impossible. Isolated hallux varus congenitus due to a delta phalanx of the proxim...

The manipulation mechanism of the giant panda (Ailuropida melanoleuca) was examined by means of CT (computed tomography) and 3-dimensional (3-D) Volume Rendering techniques. In the 3-D images of the giant panda hand, not only the bones but also the muscular system was visualised. Sections of the articulated skeleton were obtained. It was demonstrated that the hand of the panda is equipped with ...