Knee arthrodesis implant with a femur nail inserted into the medullary canal of the femur bone with a nail neck and a tibia nail inserted into the medullary canal of the tibia bone with a nail neck, the nails being attached between yes rigidly by means of a connecting element, which has at least one sleeve-like module (3, 3.1, 3.2, 3.3, 3.4, 3.5) placed in the direction of the nail axis (1； 2), characterized in that the module includes at least two half-covers (6.1； 6.2) divided in the direction of the axis (LA) of the module (3； 3.1-3.6), because the half-covers (6.1； 6.2) are joined together so that they can be released and form a pin (7 ) extending axially to introduce the corresponding nail collars (4； 5) into the pin (7) and because the half-decks have recesses (10.1) to accommodate a fastener (14), arranged coaxially in the direction of the axis of the module (3； 3.1-3.6), positioned in c if necessary perpendicular to the direction of the shaft (LA) and that they correspond to each other, that after the fixation fixes the corresponding neck of the nail (4； 5) to the pin (7) exclusively by friction grip as a jaw with a sufficient torque against axial displacement and rotation.Implante de artrodesis de rodilla con un clavo de fémur introducido en el canal medular del hueso del fémur con un cuello del clavo y un clavo de tibia introducido en el canal medular del hueso de la tibia con un cuello del clavo, estando unidos los clavos entre sí rígidamente mediante un elemento de unión, que presenta al menos un módulo a modo de manguito (3, 3.1, 3.2, 3.3, 3.4, 3.5) colocado en la dirección del eje del clavo (1； 2), caracterizado porque el módulo incluye al menos dos semicubiertas (6.1； 6.2) divididas en la dirección del eje (LA) del módulo (3； 3.1-3.6), porque las semicubiertas (6.1； 6.2) están unidas entre sí tal que pueden soltarse y configuran un pasador (7) que se extiende axialmente para introducir los correspondientes cuellos de clavo (4； 5) en el pasador (7) y p
