The invention relates to a medical tool system (1) for providing a trapezoidal recess in a joint surface of a bone, comprising a milling tool (2), which can be rotated about a tool axis (7) and which has milling edges (6) that are active on the circumferential side and milling edges (6) that are active at an axial end with respect to the tool axis (7), and comprising a template part (3), which can be fixed to the joint surface, for guiding the milling tool (2), wherein a stop (10, 19) is provided which limits a penetration depth of the milling tool (2). The medical tool system is to be designed such that the medical tool system allows a simple and reliable production of recesses with a trapezoidal cross-section in a joint surface of a bone even under spatially restricted conditions. According to the invention, this is achieved in that the template part (3) has a base element (4) with a slide guide (12) and a slide (5) which can be moved in the slide guide (12) between two end stops along a guide path lying on a guide plane. A guide channel (18), which runs diagonally to the guide plane and leads to a milling tool (2) receiving area directed transversely to the tool axis (7), is formed in the slide (5) such that the milling tool (2) can rotate freely about the tool axis (7).La invención se refiere a un sistema de herramienta médica (1) para proporcionar un rebaje trapezoidal en una superficie de la articulación de un hueso, que comprende una herramienta de fresado (2), que se puede rotar alrededor de un eje de herramienta (7) y que tiene bordes de fresado (6) que son activos en el lado circunferencial y bordes de fresado (6) que son activos en un extremo axial con respecto al eje de herramienta (7), y que comprende una parte de plantilla (3), que puede ser fijada a la superficie de la articulación, para guiar la herramienta de fresado (2), en donde un tope (10, 19) se proporciona que limita una profundidad de penetración de la herramienta de fresado (2). El sistema d
