Abstract:
Superior and/or inferior facets of one or more facet joints may be replaced by superior and/or inferior facet joint prostheses. In one embodiment, a kit of superior or inferior prostheses is provided, in which the prostheses have at least two dimensions that vary among members of the kit independently of each other. Each prosthesis may have a bone engaging surface having a surface that is polyaxially rotatable against a corresponding resection of a vertebra. Each prosthesis may also have an articulating surface shaped such that, after attachment to the spine, the replaced or partially replaced facet joints provide a larger medial-lateral range of motion when the spine is flexed than when the spine is extended. Crosslinks may be used to connect left and right prosthesis together in such a manner that they are stabilized in a position in which they are seated directly against the vertebra.
Abstract:
Superior and/or inferior facets of one or more facet joints may be replaced by superior and/or inferior facet joint prostheses. In one embodiment, a kit of superior or inferior prostheses is provided, in which the prostheses have at least two dimensions that vary among members of the kit independently of each other. Each prosthesis may have a bone engaging surface having a surface that is polyaxially rotatable against a corresponding resection of a vertebra. Each prosthesis may also have an articulating surface shaped such that, after attachment to the spine, the replaced or partially replaced facet joints provide a larger medial-lateral range of motion when the spine is flexed than when the spine is extended. Crosslinks may be used to connect left and right prosthesis together in such a manner that they are stabilized in a position in which they are seated directly against the vertebra.
Abstract:
A tool, particularly a torque-transmitting tool, such as a screwdriver or a screwdriver bit, having a shaft and a working region. In order advantageously to take up peak torques with such a tool, a damping region of lower hardness or lower torsion-bar constant than the working region is provided, associated with the shaft. For this purpose, the damping region can be subsequently annealed or have a different composition of material. The latter is preferably provided in the case of a tool of sintered metal.
Abstract:
A prosthesis for the replacement of a diseased or traumatized facet of a mammalian vertebra includes a surface that articulates with another prosthetic facet or a natural facet, a portion that replaces at least a bony portion of the diseased or traumatized spine facet which is to be replaced, and an element to attach the prosthesis to the vertebra in a manner that does not require attachment to or abutment against the posterior arch. A method of installing the prosthesis includes the steps of resecting at least a portion of a facet and attaching the prosthesis in a manner that does not require attachment or abutment against the posterior arch.
Abstract:
A prosthesis for the replacement of a diseased or traumatized facet of a mammalian vertebra includes a surface that articulates with another prosthetic facet or a natural facet, a portion that replaces at least a bony portion of the diseased or traumatized spine facet which is to be replaced, and an element to attach the prosthesis to the vertebra in a manner that does not require attachment to or abutment against the posterior arch. A method of installing the prosthesis includes the steps of resecting at least a portion of a facet and attaching the prosthesis in a manner that does not require attachment or abutment against the posterior arch.
Abstract:
Superior and/or inferior facets of one or more facet joints may be replaced by superior and/or inferior facet joint prostheses. In one embodiment, a kit of superior or inferior prostheses is provided, in which the prostheses have at least two dimensions that vary among members of the kit independently of each other. Each prosthesis may have a bone engaging surface having a surface that is polyaxially rotatable against a corresponding resection of a vertebra. Each prosthesis may also have an articulating surface shaped such that, after attachment to the spine, the replaced or partially replaced facet joints provide a larger medial-lateral range of motion when the spine is flexed than when the spine is extended. Crosslinks may be used to connect left and right prosthesis together in such a manner that they are stabilized in a position in which they are seated directly against the vertebra.
Abstract:
An apparatus is designed to attach an implant to bone in a manner that permits rotational adjustment of the implant about multiple axes prior to securement via the apparatus. The apparatus includes separate rotational and translational fasteners that can be individually locked to independently restrict rotation and translation of the implant relative to the bone. The rotational fastener includes an interpositional member, an expandable engagement member, and a rotational locking member that urges the expandable engagement member to advance along the interpositional member. The resulting expansion of the engagement member causes it to engage the implant. The rotational fastener is slidable along a fixation member implanted in the bone until the translational fastener is applied to restrict relative translation between the rotational fastener and the bone.
Abstract:
A prosthesis for the replacement of the cartilaginous structures of a spine motion segment is described. The prosthesis comprises an intervertebral disc prosthesis in combination with a facet joint prosthesis.
Abstract:
A prosthesis for the replacement of at least a portion of the bone of a facet located on a mammalian vertebra, comprising: an articulating surface that articulates with another facet; a bone contacting surface that contacts a surface of the vertebra, the articulating surface being connected to the bone contacting surface; and a fixation element that attaches the bone contacting surface to the vertebra, the fixation element being adapted for implantation into an interior bone space of a pedicle of the vertebra; wherein the prosthesis is configured so that no portion of the prosthesis contacts the posterior arch of the vertebra.
Abstract:
An injection-molded plastic handle for tools, particularly screwdrivers, having zones of plastic of different hardness, the harder plastic being nondeformable under the forces which occur as a result of the actuating load while the softer plastic permits slight elastic deformations, and having a centrally located receiving hollow space (5) for the tang of a tool blade (2), and, in order to obtain a development which is of optimized grippability and more advantageous in use, the central hollow space is located in a center part (6) having a profiled cover surface (11) around which a cover is injected, the depressions (8) resulting from the profiling of the cover surface (11) being filled with a softer plastic until obtaining an approximately circular cross-sectional shape.