Patent ID: 9211192
Filing Date: 2015-12-15
Classification: A61F

Abstract:
1. A kit-of-parts comprising: an artificial joint comprising: a first base element and a second base element that are pivotally connected to an intermediate body; a first protrusion having an elongated shape and extending from the first base element, the first protrusion having an end that is furthest away from the first base element, a length, and an outer circumferential surface; and a second protrusion having an elongated shape and extending from the second base element, the second protrusion having an end that is furthest away from the second base element, a length, and an outer circumferential surface; a first screw device that comprises a head and an axial, circular center hole, having a length formed to receive a protrusion, whereby the first screw device may be anchored to a first bone member, and wherein the center hole includes a gradual taper over at least a portion of its length with the taper of the hole having a larger diameter nearer the head; and a second screw device that comprises a head and an axial, circular center hole, having a length formed to receive a protrusion, whereby the second screw device may be anchored to a second bone member, and wherein the center hole includes a gradual taper over at least a portion of its length with the taper of the hole having a larger diameter nearer the head; wherein the first protrusion and the second protrusion are press-fitted into the holes of the first and second screw devices, respectively, thereby gripping each protrusion in place in its respective screw device, and wherein each protrusion comprises a plurality of elongated and spaced-apart protuberances arranged at its end and located on its circumferential surface such that each protuberance extends away from the respective base element in the same direction as the respective protrusion on which it is located extends away from the base element, the protuberances extending outwardly and being located at positions on the length of the protrusion that comes into contact with the taper of its respective screw device during the press-fit of each protrusion into the hole of the respective screw device such that the protuberances are deformed thereby increasing the grip between the respective protrusion and respective screw device which provides increased resistance to rotational movement of the protrusion in the screw device and provides increased resistance to longitudinal movement of the protrusion in the screw device.