Abstract: Instrumentation for implanting an artificial intervertebral disc includes static trials and a dynamic trial for determining the appropriate size of disc to be implanted, static trial holders for manipulating the static trials, inserter/impactors for inserting and removing the static trials and for inserting the artificial intervertebral discs, repositioners/extractors for repositioning and extracting the static trials or the artificial intervertebral discs, and a leveler for setting the proper position of the artificial intervertebral disc. Methods for using the same are also disclosed. Features for artificial intervertebral discs and intervertebral spacer devices useful for manipulation by the instrumentation are also disclosed.

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: 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: An orthopedic spacer device comprising a spacer body having an external surface that includes at least two relative angle designation marks such that a rotational angle of the spacer body relative to a known reference is determinable.

Abstract: An intervertebral implant includes a first plate having an inner surface, an outer surface, a ball shaped protuberance projecting from the inner surface and an annular groove surrounding the ball shaped protuberance. The implant includes a second plate having an inner surface, an outer surface, a curvate socket formed in the inner surface of the second plate and a raised rim surrounding the curvate socket. The first and second plates are assembled together so that the inner surfaces of the plates oppose one another and the ball shaped protuberance is disposed in the curvate socket and the annular groove aligned with the raised rim. The assembled first and second plates angulate and rotate relative to one another.

Abstract: Artificial disc replacements (ADRs) and total disc replacements (TDRs) are based upon two, directly articulating components, resulting in a restricted-motion system that better approximates more normal spinal flexion, extension, and lateral bending. One component may have a concave articulating surface, and the other a convex articulating surface. The radius of curvature of the articulating surface may be smaller in the anterior-to-posterior direction of the ADR than the radius of curvature of the articulating surface in the left-to-right direction of the ADR. Both components are preferably made of a hard material and are highly polished to reduce friction.

Abstract: An intervertebral implant includes a first plate having an inner surface, an outer surface, a ball shaped protuberance projecting from the inner surface and an annular groove surrounding the ball shaped protuberance. The implant includes a second plate having an inner surface, an outer surface, a curvate socket formed in the inner surface of the second plate and a raised rim surrounding the curvate socket. The first and second plates are assembled together so that the inner surfaces of the plates oppose one another and the ball shaped protuberance is disposed in the curvate socket and the annular groove aligned with the raised rim. The assembled first and second plates angulate and rotate relative to one another.

Abstract: A dynamic distractor is described for distracting an intervertebral space and determining a size of an artificial intervertebral disc to be implanted in the intervertebral space.

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: An intervertebral spacer device may include first and second plates, each having inner and outer surfaces thereof, the plates may be disposed in a spaced apart relationship such that the inner surfaces face toward one another, and the outer surfaces face away from one another, the first plate including a retaining wall extending outwardly from the inner surface of the first plate; and a belleville washer, having narrow and wide ends thereof, may be disposed with said wide end contacting said inner surface of said first plate within said retaining wall, such that a compressive load applied to the outer surfaces of said plates is counteracted by said belleville washer, said belleville washer including a plurality of radially spaced concentric groove.

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: 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 a restoring force providing element disposed between the inner surfaces of the plates. The restoring force providing element includes a 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. The second plate has an annular groove formed in the inner surface of the second plate, the device including a retaining wall and a retaining ring, whereby a wide end of the belleville washer is captured by the retaining wall and the retaining ring for maintaining the wide end adjacent the inner surface of the second plate.

Abstract: Artificial disc replacements (ADRs) and total disc replacements (TDRs) are based upon two, directly articulating components, resulting in a restricted-motion system that better approximates more normal spinal flexion, extension, and lateral bending. One component has a concave articulating surface, and the other with a convex articulating surface. The radius of curvature of the articulating surface is smaller in the anterior to posterior direction of the ADR than radius of curvature of the articulating surface in the left to right direction of the ADR. The use of an articulating surface with two or more radius of curvature also limits axial rotation, thereby protecting the facet joints and the Annulus Fibrosus (AF). The two different radii used to create the articulating surfaces also naturally leads to an oval shape as seen from the top, which better fits the oval shape of the vertebral endplate better than circularly shaped ADRs.

Abstract: A distraction method including inserting a spacer element into a space between bones to be distracted, removing the spacer element from the space, inserting a wider spacer element into the space, and removing the wider spacer element from the space.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces. Each of the opposing plates has an external surface with a deflectable wire mesh thereon, into which the bone can readily grow.

Abstract: An intervertebral spacer has curvate upper and lower rough surfaces that stimulate bone growth and is formed from a porous material that facilitates bone growth thereinto. The spacer has a plurality of smooth linear grooves to facilitate insertion of the spacer into an intervertebral space using a spacer insertion tool that has a scissor-style body. Each of the insertion tool's arm's heads has an inner surface having a pair of smoothed linear protrusions that fit within the linear grooves of the spacer when the heads are closed about the spacer. When the spacer is held, spaces are present between the spacer's rough surfaces and the heads' inner surfaces so that when the protrusions are longitudinally slid from the grooves to leave the spacer in the intervertebral spacer, the rough surfaces are not disturbed.

Abstract: An instrument for inserting an implant between vertebral bodies, including a holder adapted to hold the implant during insertion of the implant between the vertebral bodies, a retractor adapted to retract the holder away from the implant after the insertion, and a guard adapted to prevent the implant from being removed from between the vertebral bodies during the retraction.

Abstract: An intervertebral spacer has curvate upper and lower rough surfaces that stimulate bone growth and is formed from a porous material that facilitates bone growth thereinto. The spacer has a plurality of smooth linear grooves to facilitate insertion of the spacer into an intervertebral space using a spacer insertion tool that has a scissor-style body. Each of the insertion tool's arm's heads has an inner surface having a pair of smoothed linear protrusions that fit within the linear grooves of the spacer when the heads are closed about the spacer. When the spacer is held, spaces are present between the spacer's rough surfaces and the heads' inner surfaces so that when the protrusions are longitudinally slid from the grooves to leave the spacer in the intervertebral spacer, the rough surfaces are not disturbed.

Abstract: An instrument for inserting an implant between vertebral bodies, including a holder adapted to hold the implant during insertion of the implant between the vertebral bodies, a retractor adapted to retract the holder away from the implant after the insertion, and a guard adapted to prevent the implant from being removed from between the vertebral bodies during the retraction.

Abstract: Instrumentation for implanting an artificial intervertebral disc includes static trials and a dynamic trial for determining the appropriate size of disc to be implanted, static trial holders for manipulating the static trials, inserter/impactors for inserting and removing the static trials and for inserting the artificial intervertebral discs, repositioners/extractors for repositioning and extracting the static trials or the artificial intervertebral discs, and a leveler for setting the proper position of the artificial intervertebral disc. Methods for using the same are also disclosed. Features for artificial intervertebral discs and intervertebral spacer devices useful for manipulation by the instrumentation are also disclosed.