[Extension according to Matev in malformations of the hands (author's transl)].

Step-by-step distraction of the metacarpal I according to Matev in traumatic loss of the thumb is demonstrated in a modified form with interposition of a corticospongious bone chip. Subsequently, the article reports on the use of this method in congenital malformations of the hand on the basis of three different examples.--Firstly, monodactyly with extension of a second metacarpal as passive counter-support,--Secondly, symbrachydactyly with rudimentary metacarpal rests I to V with extension of I and then of III and IV, followed by subtotal resection of the second metacarpal stump and phalangisation, and--Thirdly, bilateral severe malformation of the hand through amniotic segmentations and exogenous syndactylies with extension of metacarpal I, ligamental transposition and commissural deepening. The results show that--provided indication is strict on account of the almost always satisfactory substitute grasping actions in congenital malformations of the hand--an effective improvement of the grasping function can be achieved in selected individual cases by means of Matev's method.