Instrument for use in a joint replacement surgery.

摘要

A kit for use in a surgical procedure to replace a shoulder joint, comprising: an implant component having a proximal metaphyseal part and a stem portion distal which extends beyond the proximal metaphyseal part and component trial implant comprising (i) a portion of test head which has a bearing surface test for engagement in a corresponding bearing surface of the joint, and a first part of an assembly spigot and socket, and (ii) a metaphyseal part (32) having on its upper face a second part (44) assembly spigot and socket so that the part can be mounted on the upper face of the metaphyseal part, defining the assembly pin and fossa assembly axis, in which the ratio of the length of the metaphyseal part measured between the top and bottom along the axis of the assembly with respect to its faces to nchura as the top face (34) generally along the medial-lateral axis is not more than about 1.0, in quel: a. the peripheral edge of the upper face of the metaphyseal part of the implant component test defines a first plane and the peripheral edge of the lower face of the metaphyseal part defines a second plane in which the angle between the first and second planes is not greater than 20 °, b. the metaphyseal part of the implant component test can be positioned to extend into a cavity in the resected face of the humeral in contact with the inner wall of the cavity in the metaphyseal region, and has a plurality of ribs (38, 40 , 42) extending axially along its side wall, which can be received in a corresponding groove existing in an inner wall of the humerus, to locate the metaphyseal part rotationally in the cavity, c. the ratio of surface area of ​​the metaphyseal part of the implant component, not including the ends of the ribs, on its upper face (34) relative to the surface area on its upper face (36) is not greater than about 2.0 .