DEVICE FOR COMPRESSION SCREWING

摘要

Device for compression screwing fractures of the femural neck, consisting of a plate of a sleeve, the sleeve being hollow and cylindrical in shape, the plate of the sleeve beign attached by screws to the femur shaft and of a bone screw being located within the sleeve which is provided with a female thread on its head side into which compression screw having a respective male thread fits, whereby the compression screw is supported by means of the bottom edge of its head or by a respective, especially conical contact surface for the limitation of its movement against a fixing ring being located within the sleeve in such a way that it can be displaced, sliding with its surface along the inner surface of the sleeve and having a conical surface in an acial direction that is adapted to the bottom edge of the head of the compression screw and the cone angle of which is sized in such a way that the adhesive friction between the outer surface of the fixing ring and the inner surface of the sleeve is greater than the compressional force acting in the longitudinal direction of the screw.