Abstract: An artificial disc having a pair of opposing baseplates, for seating against opposing vertebral bone surfaces, separated by a ball and socket joint that includes a ball compression locked to a post extending from one of the baseplates. The ball is captured within a curvate socket formed in a peak of a convex structure attached to the other of the baseplates. The socket is formed by opposing curvate surfaces, one on the convex structure and one on the other of the baseplates. While the ball angulates freely in the socket, the rotation of the ball in the socket has a limited range due to interference between a protrusion on the convex structure that extends into the socket and a curvate recess on the ball. The ball and socket joint therefore permits the baseplates to rotate relative to one another through a limited range and also angulate relative to one another.

Abstract: An intervertebral spacer device includes first and second plate members, each having plate surfaces thereof, the plate members being disposed in a spaced apart relationship such that inner ones of the plate surfaces oppose one another, and external ones of the plate surfaces face in opposite directions. The device includes at least one slotted domed arch strip spring disposed between the inner surfaces of the first and second plate members for counteracting compressive load applied to the external surfaces of the plate members, one of the plate members having a ball-shaped head attached thereto and spaced from the inner surface thereof, and the at least one slotted domed arch strip spring having a central opening including a curvate volume for receiving and holding therein the ball-shaped head.

Abstract: An instrument for insertion, implanting, and removing a cylindrical intervertebral spacer member having a deep circumferential groove, including: a shaft having a proximal end and a distal end, said proximal end forming a handle and the distal end forming a spacer member engaging subassembly; said spacer member engaging subassembly including at least one selectively expanding and contracting enclosure into which a central core of the spacer member may be introduced when the engaging subassembly is in the expanded state, and which holds the spacer member so that it cannot move when the selectively expanding and contracting enclosure is rendered into the contracted state; and an actuating mechanism, extending from the proximal end to the distal end, by which the spacer member engaging subassembly may be selectively expanded and contracted.

Abstract: An apparatus for replacing at least a portion of an intervertebral disc in a spinal column includes: a first member having a first vertebral contact surface for engagement with an endplate of a first vertebral bone in the spinal column and a first articulating surface having a single saddle surface; and a second member having a second vertebral contact surface for engagement with an endplate of a second vertebral bone in the spinal column and a second articulating surface having a single saddle surface wherein: an intervertebral disc space is defined substantially between the first and second endplates of the first and second vertebral bones, and the first and second members are operable to articulate relative to one another, when disposed in the intervertebral disc space, about at least one of: (i) a first center of rotation for at least one of flexion and extension that is located above the first and second articulating surfaces outside the intervertebral disc space, and (ii) a second center of rotation for

Abstract: An apparatus for replacing at least a portion of an intervertebral disc in a spinal column includes: a first member having a first vertebral contact surface for engagement with an endplate of a first vertebral bone in the spinal column, and having a first articulation surface; and a second member having a second vertebral contact surface for engagement with an endplate of a second vertebral bone in the spinal column, and having a second articulation surface, wherein: an intervertebral disc space is defined substantially between the first and second endplates of the first and second vertebral bones, and at least one of the first and second articulation surfaces is a saddle shaped surface, and the articulation surfaces are sized and shaped to engage one another when the first and second members are disposed in the intervertebral disc space to enable the first and second vertebral bones to articulate in at least one of flexion, extension, and lateral bending.

Abstract: Spacerless artificial disc replacements (ADR) are disclosed. One preferred embodiment includes two saddle-shaped components to facilitate more normal spinal flexion, extension, and lateral bending while limit axial rotation, thereby protecting the facet joints and the annulus fibrosus (AF). Either or both of the superior and inferior components are made of a hard material such as chrome cobalt, titanium, or a ceramic including alumina, zirconia, or calcium phosphate. The articulating surfaces of the ADR are also preferably highly polished to reduce friction between the components. Metals, alloys or other materials with shape-memory characteristics may also prove beneficial.

Abstract: A method for replacing at least a portion of an intervertebral disc in a spinal column includes: removing the portion of the intervertebral disc from the spinal column; and inserting an apparatus for replacing the portion of the intervertebral disc into an intervertebral disc space defined substantially between adjacent vertebral bones of the spinal column, and positioning the apparatus between the vertebral bones, wherein the apparatus is operable to permit the adjacent vertebral bones to articulate relative to one another about at least one of: (i) a first center of rotation for at least one of flexion and extension that is located outside the intervertebral disc space, and (ii) a second center of rotation for lateral bending that is located outside the intervertebral disc space.

Abstract: A method for replacing at least a portion of an intervertebral disc in a spinal column includes: removing the portion of the intervertebral disc from the spinal column; and inserting an apparatus for replacing the portion of the intervertebral disc into an intervertebral disc space defined substantially between adjacent vertebral bones of the spinal column, and positioning the apparatus between the vertebral bones, wherein the apparatus is operable to permit the adjacent vertebral bones to articulate relative to one another about at least one of: (i) a first center of rotation for at least one of flexion and extension that is located outside the intervertebral disc space, and (ii) a second center of rotation for lateral bending that is located outside the intervertebral disc space.

Abstract: A method for replacing at least a portion of an intervertebral disc in a spinal column includes: removing the portion of the intervertebral disc from the spinal column; and inserting an apparatus for replacing the portion of the intervertebral disc into an intervertebral disc space defined substantially between adjacent vertebral bones of the spinal column, and positioning the apparatus between the vertebral bones, wherein the apparatus is operable to permit the adjacent vertebral bones to articulate relative to one another about at least one of: (i) a first center of rotation for at least one of flexion and extension that is located outside the intervertebral disc space, and (ii) a second center of rotation for lateral bending that is located outside the intervertebral disc space.

Abstract: An intervertebral spacer device includes first and second plates disposed in a spaced apart relationship, each plate having an inner surface and an outer surface, the inner surfaces of the opposing plates facing one another. The device also includes at least one restoring force providing element disposed between the inner surfaces of the plates, wherein a compressive load applied to the outer surfaces of the first and second plates is counteracted by the at least one restoring force providing element. The at least one restoring force providing element includes at least one slotted belleville washer having a convex shape when unloaded and a flatter shape when loaded, whereby one or more slots of the belleville washer widen when compressively loaded, and whereby the at least one slotted belleville washer is unloaded when no load is applied to the outer surfaces of the first and second plates, and is loaded when the compressive load is applied to the outer surfaces of the first and second plates.

Abstract: An intervertebral device includes a first plate having an outer face and an inner face, and a second plate juxtaposed with the first plate, the second plate having an outer face, an inner face that opposes the first plate and a concavity that opposes the first plate. The device includes an elongated member extending from the first plate toward the second plate, the elongated member having a distal end with a spherical surface that is engageable with the concavity of the second plate for providing an articulating joint between the first and second plates. The device also includes a resilient member in contact with the elongated member for counteracting compressive loads on the plates, the resilient member being surrounded by the concavity of the second plate.

Abstract: A porous intervertebral spacer having a flexible wire mesh as a vertebral body contact surface, the flexible wire mesh preferably being a convex titanium mesh laser-welded at its perimeter to the spacer. The mesh is domed in its initial undeflected conformation, but deflects as necessary during insertion of the spacer between vertebral bodies, and, once the spacer is seated between the vertebral bodies, deforms as necessary under anatomical loads to reshape itself to the concave surface of the vertebral endplate, providing gripping and holding strength upon initial implantation, and an osteoinductive surface through which the bone may ultimately grow, making the fixation of the spacer between the vertebral bodies secure.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by a spring mechanism. The preferred spring mechanism is a slotted domed arch strip spring which is coupled to the upper plate by set screws. The spring includes a socket formed in the peak thereof and mounts onto a ball-shaped head extending outwardly from the lower plate. The spring and post members are thereby flexibly coupled such that the upper and lower plates may rotate relative to one another.

Abstract: An intervertebral spacer device includes first and second plates having plate surfaces, the first and second plates being spaced from one another with inner ones of the plate surfaces opposing one another and external ones of the plate surfaces facing in opposite directions. The spacer device includes at least one domed arch strip spring disposed between the inner surfaces of the first and second plate members for counteracting compressive loads applied to the external surfaces of the first and second plates. The at least one domed arch strip spring has lateral ends that are coupled with the first plate and a curvate central portion that is maintained adjacent the inner surface of the second plate.

Abstract: An artificial disc having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by at least one spring mechanism. The preferred spring mechanism is at least one spirally slotted belleville washer, and in some embodiments the belleville washer is also radially thinning or thickening. Various illustrated embodiments use two washers or one washer. For double washer embodiments, the wide ends of the washers seat against respective opposing plates, in some embodiments each being maintained thereagainst by a retaining wall and ring or a circular recess and retaining shield. For single washer embodiments, the narrow end of the washer can be modified to have a curvate socket for rotatably mounting onto a semispherical protuberance extending from one of the plates.

Abstract: An articulating joint implant for use in the cervical spine includes a pair of opposing upper and lower elements having nested articulation surfaces providing a center of rotation of the implant above the adjacent vertebral body endplate surfaces in one mode of motion lateral bending and a center of rotation of the implant below those surfaces in flexion/extension, and that further permit axial rotation of the opposing elements relative to one another about the longitudinal axis of the spinal column through a range of angles without causing them to move in opposing directions along the longitudinal axis within that range. In preferred embodiments, the articulation surfaces further cause such opposite movement of the opposing elements beyond that range.

Abstract: An intervertebral spacer device includes a first plate having a bone engaging face and an inner face, and a second plate having a second bone engaging face and a second inner face, the first and second plates being juxtaposed with one another so that the first inner face of the first plate opposes the second inner face of the second plate. The spacer device also includes a belleville washer disposed between the first inner face of the first plate and the second inner face of the second plate for counteracting compressive loads applied to the first and second plates. The belleville washer has at least one concentric groove and at least one spiral slot, whereby the at least one concentric groove has a depth and a width, with at least one of the widths and the depths varying along the length of the at least one concentric groove.

Abstract: Instrumentation for implanting a cervical disc replacement device includes cervical disc replacement trials for determining the appropriate size of replacement device to be implanted, an insertion plate for maintaining the elements of the replacement device in fixed relation to one another for simultaneous manipulation, an insertion handle for attachment to the insertion plate for manipulation of the elements, an insertion pusher for releasing the insertion handle from the insertion plate, a drill guide that cooperates with the insertion plate to guide the drilling of tap holes for bone screws to be placed through bone screw holes in the flanges of the replacement device, clips that are applied to the flanges after placement of the bone screws to resist screw backout, and a clip applicator for applying the clips to the flanges.

Abstract: A surgical treatment for restoring proper anatomical spacing and alignment to vertebral bones including: determining an angular misalignment associated with adjacent vertebral bones; sequentially inserting and removing a series of progressively wider spacer elements into the corresponding intervertebral space between the adjacent vertebral bones until the proper anatomical spacing between the adjacent vertebral bones is restored; for each intervertebral space, inserting a tapered porous spacer element into the intervertebral space between the corresponding adjacent vertebral bones; rotating the tapered porous spacer element such that the rotational orientation of the tapered porous spacer element introduces the appropriate counter offset to the intervertebral space of the previously misaligned scoliotic vertebral bones, thereby restoring the proper anatomical alignment of the vertebral bones; and stabilizing the adjacent vertebral bones to permit infused growth of bone into the tapered porous spacer element.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by a spring mechanism. The preferred spring mechanism is a domed arched strip spring which is coupled to the upper plate by set screws. The spring includes a socket formed in the peak thereof and mounts onto a ball-shaped head extending outwardly from the lower plate. The spring and post members are thereby flexibly coupled such that the upper and lower plates may rotate relative to one another.