An articulated medical instrument (100) comprising: a substantially straight proximal segment (130, 510)； a substantially straight distal segment (140, 530) connected to the proximal segment (130)； an articulation mechanism for changing an articulation angle (135) between the proximal and distal segments and providing a straight configuration in which the proximal and distal segments form a substantially straight line and at least one articulated configuration in which the proximal and distal form an articulation angle of less than 180 degrees between the segments, the articulation mechanism being configured to increase or reduce the articulation angle； and one or more drive mechanisms (150, 220, 320, 420, 520, 580) configured to transfer a rotating movement from the proximal segment to the distal segment, characterized in that said at least one mechanism (150, 220, 320, 420, 520 , 580) of drive for transferring a rotating movement is contained in the segments in the straight configuration, wherein at least a portion of said at least one driving mechanism for transferring the rotating movement is external to at least a portion of at least a segment adjacent to the connection between the segments in the articulated configuration.Un instrumento médico articulado (100) que comprende: un segmento proximal sustancialmente recto (130, 510)； un segmento distal sustancialmente recto (140, 530) conectado con el segmento proximal (130)； un mecanismo de articulación para cambiar un ángulo (135) de articulación entre los segmentos proximal y distal y proporcionar una configuración recta en la que los segmentos proximal y distal forman una línea sustancialmente recta y al menos una configuración articulada en la que los segmentos proximal y distal forman un ángulo de articulación inferior a 180 grados entre los segmentos, estando configurado el mecanismo de articulación para aumentar o reducir el ángulo de articulación； y uno o más mecanismos (150, 220, 320, 420, 520, 580) de ac
