The hand of the musician: the kinematics of the bidigital finger system with anatomical restrictions.

Tendons of the fingers are frequently interconnected by anatomic structures that limit the displacements of these tendons relative to each other. In this paper a bidigital finger system in which such interconnections between tendons are present is kinematically modelled. Using this model, an exhaustive description of the effects on finger movement of connections between the different tendons of the fingers is given. The study provides a context for the interpretation of typical difficulties of finger coordination in musicians, especially in pianists and string players.