The invention relates to a device for the in-situ production of articularspacers from a bonecement, comprising a punch surface (1) for forming an articulation surface ofa spacer in thebone cement, whereby the bone cement is arranged on a bone surface forfixation of the spacer,whereby the punch surface (1) comprises a negative image of the articulationsurface to beproduced, and the surface forming the negative image is open on the side, atleast in part, suchthat the bone cement can be pushed towards the side, away from thearticulation surface to beformed.The invention also relates to a set comprising two of said devices, wherebythe first device isintended for forming the articulation surface of a first articular spacer andthe second device isintended for forming the articulation surface of a second articular spacer,whereby the twoarticulation surfaces touch against each other and form the sliding surfacesof the articularspacer in the patient-inserted state such that the articular spacer assumesthe function of thebones of the respective joint, preferably of a knee joint.Moreover, the invention also relates to the use of said device and a methodfor producing anarticular spacer on a bone (19), in particular the bone surface, comprisingthe followingchronological procedural steps:A) Applying a bone cement to a prepared boneB) Pressing said device onto the bone cement andC) Detaching the device from the cured bone cement.
