Abstract: A pedicle screw is provided. The pedicle screw includes a threaded shaft portion and a head portion that is supported on the threaded shaft portion for pivoting movement relative to the threaded shaft portion. A yoke portion is supported on the head portion for linear sliding movement relative to the head portion.

Abstract: A double-headed pedicle screw is provided. The double-headed pedicle screw includes a threaded shaft portion and a plurality of yoke assemblies supported by the threaded shaft portion. Each of the yoke assemblies includes a recess configured to receive a portion of a rod, alignment structure, or immobilization structure therein. Each of the yoke assemblies is configured for pivoting movement relative to the threaded shaft portion independent of the pivoting movement of the other yoke assemblies.

Abstract: A double-headed pedicle screw is provided. The double-headed pedicle screw includes a threaded shaft portion and a plurality of yoke assemblies supported by the threaded shaft portion. Each of the yoke assemblies includes a recess configured to receive a portion of a rod, alignment structure, or immobilization structure therein. Each of the yoke assemblies is configured for pivoting movement relative to the threaded shaft portion independent of the pivoting movement of the other yoke assemblies.

Abstract: A disc prosthesis comprising an upper cover provided with a cavity and a curved surface; a bearing member comprising an outer surface, on which the upper cover can rotate and received by the cavity, and at least one mount; a movement member which is provided with an outer surface compatible with an inner surface of the mount, and which is received by the mount so as to move concurrently with the upper cover; a lower cover provided with a cavity to receive said mount and a curved surface; and a connection member extending from the cavity towards the lower cover and being mounted to the movement member by being passed through a channel which extends along the bearing member and is in connection with said mount so as to connect the bearing member to the upper cover.

Abstract: A pedicle screw is provided. The pedicle screw includes a threaded shaft portion and a head portion that is supported on the threaded shaft portion for pivoting movement relative to the threaded shaft portion. A yoke portion is supported on the head portion for linear sliding movement relative to the head portion.

Abstract: A disc prosthesis comprising an upper cover provided with a cavity and a curved surface; a bearing member comprising an outer surface, on which the upper cover can rotate and received by the cavity, and at least one mount; a movement member which is provided with an outer surface compatible with an inner surface of the mount, and which is received by the mount so as to move concurrently with the upper cover; a lower cover provided with a cavity to receive said mount and a curved surface; and a connection member extending from the cavity towards the lower cover and being mounted to the movement member by being passed through a channel which extends along the bearing member and is in connection with said mount so as to connect the bearing member to the upper cover.