Abstract: An apparatus for testing an articulating implant includes a support structure in contact with a first part of the implant, an adapter coupled to a second part of the implant, a load assembly coupled with the adapter for applying a load onto the adapter, and a drive assembly coupled with the adapter. Operation of the drive assembly causes angulation and rotation of the adapter relative to the support structure, which in turn causes angulation and rotation of the first and second parts of the implant relative to one another.

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: An artificial disc having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by a spider spring having a plurality of spring arms extending radially from a central hub. Various spring arm embodiments disclosed include spring arms that are straight, bowed, grooved, wavy, thinning, or thickening; and spring arms with parallel sides, radially outwardly diverging sides, or radially outwardly diverging and curving sides. Various spider spring embodiments disclosed include spider springs with central hubs that are solid, bored, have curvate sockets, or have semispherical protuberances. Various plate embodiments disclosed include plates having, on inwardly facing surfaces, a curvate socket, a semispherical protuberance, a circular recess, or a flat surface.

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 solid ball mounted to protrude from one of the baseplates. The ball is captured within a curvate socket formed in a peak of a convex structure integral with the other of the baseplates. The socket is formed by opposing curvate pockets, one on vex structure and one on a cap secured to the other of the baseplates. While the ball angulates in the socket, its rotation in the socket has a limited range due to interference between an interference pin's rounded head 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: Instrumentation for distracting an intervertebral space and determining an appropriate size for an artificial intervertebral disc to be implanted therein include static trials and a static trial holder for manipulating the static trials. Each static trial is provided with at least one notch that is engaged by the static trial holder when the static trial is being manipulated thereby, to limit or prevent rotation of the static trial about a longitudinal axis with respect to the static trial holder during the manipulation.

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. The ball rotates and angulates in the socket. The ball and socket joint therefore permits the baseplates to rotate and angulate relative to one another.

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 an interference pin's rounded head 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 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 in the socket, its rotation in the socket has a limited range due to interference between a protrusion on the ball that extends into a curvate recess adjacent the curvate socket. 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 apparatus for testing an articulating implant includes a support structure in contact with a first part of the implant, an adapter coupled to a second part of the implant, a load assembly coupled with the adapter for applying a load onto the adapter, and a drive assembly coupled with the adapter. Operation of the drive assembly causes angulation and rotation of the adapter relative to the support structure, which in turn causes angulation and rotation of the first and second parts of the implant relative to one another.

Abstract: An intervertebral spacer device having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by a subassembly including a ball captured in a curvate volume, at least a portion of the curvate volume being formed in a convex element that is maintained against a first plate by a retaining wall and a retaining ring.

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 solid ball mounted to protrude from one of the baseplates. The ball is captured within a curvate socket formed in a peak of a convex structure integral with the other baseplate. The socket is formed by opposing curvate pockets, one on the convex structure and one on a cap secured to the other baseplate. While the ball angulates in the socket, its rotation in the socket has a limited range due to interference between a protrusion on the ball that extends into a curvate recess, formed by the convex structure and the cap, adjacent the curvate socket. 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 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 ball bearing and curvate recesses on the convex structure and 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 apparatus for testing an implant having first and second components coupled together by an articulating ball and socket joint includes a support structure in contact with the first component of the implant for supporting said implant, an adapter coupled to the second component of the implant, and a load assembly in contact with the adapter for applying a load onto a semispherical surface of the adapter. The apparatus includes a drive assembly coupled with the adapter having a first drive shaft having a first end connected with a center of a rotatable wheel and a second drive shaft having a first end connected with an outer region of the wheel and a second end connected to the adapter. The second drive shaft has a longitudinal axis that is at an angle relative to the longitudinal axis of the first drive shaft.

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 solid ball mounted to protrude from one of the baseplates. The ball is captured within a curvate socket formed in a peak of a convex structure integral with the other of the baseplates. The socket is formed by opposing curvate pockets, one on the convex structure and one on a cap secured to the other of the baseplates. While the ball angulates in the socket, its rotation 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 having a pair of opposing plates for seating against opposing vertebral bone surfaces, separated by a spring mechanism. The preferred spring mechanism is a multi-pronged domed 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: A wedge plate inserter/impactor instrument is provided primarily for holding, inserting, repositioning, removing, impacting, extracting, and otherwise manipulating an artificial intervertebral disc having features suitable for being manipulated thereby. A spring-loaded holding pin of the instrument can be used to engage a corresponding hole on the disc and confront the angled surfaces of the disc to enable the holding and manipulation of the disc. A forward wedge extension of the inserter/impactor has upper and lower surfaces that engage inwardly facing surfaces of the disc to hold the baseplates of the disc at a preferred lordosis angle with respect to one another. The instrument can engage the disc from a variety of surgical approach angles.

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 that is defined by a plurality of concave arcs each having a respective radius of curvature about a corresponding axis substantially perpendicular to an anterior-posterior plane of the spinal column, and a plurality of convex arcs each having a respective radius of curvature about a corresponding axis substantially perpendicular to a lateral plane of the spinal column; 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 that is defined by a plurality of convex arcs each having a radius of curvature about a corresponding axis substantially perpendicular to the anterior-posterior plane of the spinal column, an

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 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 that is defined at least by a concave arc having a radius of curvature A about a first axis substantially perpendicular to an anterior-posterior plane of the spinal column, and by a convex arc having a radius of curvature B about a first axis substantially perpendicular to a lateral plane of the spinal column; 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 that is defined at least by a convex arc having a radius of curvature C about a second axis substantially perpendicular to the anterior-posterior plane of the spinal column, and by a concave arc having a radius of curvature D about a second axis subst

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. The apparatus is operable to permit respective vertebral bones of the spinal column between which the apparatus is positioned to articulate in flexion and extension in an anterior-posterior plane of the spinal column, lateral bending in a lateral plane of the spinal column, and axial rotation through a range of angles without permitting the vertebral bones to substantially move in directions directed away from one another along a longitudinal axis of the spinal column.