Abstract: An intervertebral disc includes a superior endplate having an upper vertebral contacting surface and a lower bearing surface, wherein the upper vertebral contacting surface of the superior endplate has a central portion that is raised relative to a peripheral portion of the superior endplate, and wherein the lower bearing surface has a concavity disposed opposite the raised central portion. The disc includes an inferior endplate having a lower vertebral contacting surface and an upper surface, wherein the lower vertebral contacting surface of the inferior endplate has a central portion and wherein the upper bearing surface has a concavity disposed opposite the central portion. A core is positioned between the upper and inferior endplates, the core having upper and lower core bearing surfaces configured to mate with the bearing surfaces of the upper and inferior endplates.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae includes an upper plate, a lower plate and a core. The core is retained between the upper and lower plates by a retention feature in the form of central projections on the plates and a corresponding opening in the core. The retention feature is designed to allow the plates to slide over the upper and lower surfaces of the core in the anterior/posterior direction and in the lateral direction and to allow the plates to rotate with respect to each other and the core. The retention feature is also designed to prevent contact between the first and second plates during sliding movement of the plates over the core. Each central projection has a diameter that is smaller than a smallest diameter of a central opening of the core.

Abstract: A method for inserting an intervertebral disc prosthesis into a space between two vertebrae involves inserting the prosthesis partway into the space under constraint to prevent endplates of the prosthesis from articulating, releasing the prosthesis from constraint, and inserting the unconstrained prosthesis farther into the space. In some embodiments, the method involves grasping the prosthesis with a grasping device to insert the prosthesis partway under constraint, loosing the grasping device to release the prosthesis from constraint, and pushing the prosthesis farther into the disc space using the grasping device and/or one or more separate pusher devices. A system includes a grasping device, at least one separate pushing device, and optionally a vertebral spreading device and/or a vertebral midline indicator device.

Abstract: Systems and methods are provided for robotically assisted disc prosthesis selection and implantation. The system includes a 3D modeling system for creating a 3D model of first and second vertebra adjacent the intended surgical site and identifying and storing data for the positions of the first and second vertebrae. A computing system for stores and processes the 3D model and the position data. A robot connected to the computing system attaches to a plurality of instruments including sizing templates, trials, cutters or placement instruments for intervertebral disc prostheses. An interface on the computing system allows the surgeon to sequentially deliver the plurality of instruments with the robot to a registration position to improve the speed and accuracy of the surgical procedure.

Abstract: Systems and methods for robotically distracting a disc space are provided for implantation of an intervertebral prosthetic disc. The system includes a 3D modeling system for creating a 3D model of first and second vertebra adjacent the disc space and identifying positions of the first and second vertebrae. A robotic distractor precisely opens the disc space just large enough to receive a selected intervertebral disc. A computing system stores and processes the 3D model and the positions of the first and second vertebrae before and after distraction. A surgeon interface on the computing system allows the surgeon to select an intervertebral disc prosthesis to be implanted and a desired distraction distance or force to be achieved.

Abstract: A prosthetic disc for insertion between adjacent vertebrae includes a core having upper and lower curved surfaces, upper and lower plates, and peripheral restraining structure on at least one of the upper plate, the lower plate and the core. Each plate has an outer surface which engages a vertebra and an inner curved surface which slides over the curved surface of the core. The peripheral restraining structure serves to hold the core against a curved surface of at least one of the plates during sliding movement of the plates over the core.

Abstract: A dynamic intervertebral spacer includes a ring which is split on an anterior portion. A posterior portion of the ring acts as a torsion spring. After implantation, the ring is able to act as a spring between superior and inferior vertebral bodies, thus allowing dynamic bone growth in fusion procedures.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae includes upper and lower prosthesis plates locatable against respective vertebrae and having opposing concavely curved recesses therein, and a core located between the plates. The core has opposed, convexly curved surfaces received in the recesses of the plates to allow the plates to slide in articulated manner over the core. The opposed surfaces of the core and the recesses of the plates have cooperating spherical curvatures. The recess of each plate surrounds a locating peg projecting centrally from the base of the recess and is bounded by an annular rim, such that the annular rims of the plates are arranged to contact one another at a predetermined limit of sliding movement of the plates over the core. The peg locates loosely in an opening located centrally in a curved surface of the core, whereby the plates can slide over the core in all directions while the peg holds the core captive.

Abstract: Surgical instruments, systems and methods are described for selecting a size and cutting bone for inserting of an intervertebral disc prosthesis. The surgical instrument includes a combined intervertebral disc prosthesis sizing trial and a slot or channel cutter which is movable with respect to the sizing trial.

Abstract: Systems and methods for robotically preparing a disc space are provided for implantation of an intervertebral prosthetic disc. The system includes three-dimensional modeling to identify positions of vertebrae adjacent a surgical site and a disc selection interface in a computing system to allow the surgeon to select an intervertebral disc prosthesis for implantation. A bone cutting interface allows the surgeon to determine a bone cutting pattern tailored to both the three-dimensional positions of the vertebrae and the selected intervertebral disc. A robot controls a cutting device or guides a cutting device to cut the vertebral bone in the bone cutting pattern.

Abstract: A prosthetic intervertebral disc is formed of first and second end plates sized and shaped to fit within an intervertebral space and to be implanted from the back of the patient, thereby decreasing the invasiveness of the procedure. The posterior approach provides for a smaller posterior surgical incision and avoids important blood vessels located anterior to the spine particularly for lumbar disc replacements. The first and second plates are each formed of first, second and third parts are arranged in a first configuration in which the parts are axially aligned to form a low profile device appropriate for insertion through the small opening available in the TLIF or PLIF approaches described above. The three parts of both of the plates rotate and translate with respect to one another in situ to a second configuration or a deployed configuration in which the parts are axially unaligned with each other to provide a maximum coverage of the vertebral end plates for a minimum of insertion profile.

Abstract: A prosthetic disc for insertion between adjacent vertebrae includes upper and lower plates, a core disposed between the plates, and at least one projection extending from at least one of the upper and lower curved surfaces of the core into at least one recess of one of the inner surfaces of the plates. The recess is oversize with respect to the projection to allow sliding movement of the plate over the core while retaining the core between the plates during such sliding movement. The projection(s) may include a rod extending through an axial hole in the core, multiple surface features of the core, or the like.

Abstract: An intervertebral spacer is designed particularly for patients who are not candidates for total disc replacement. The spacer maintains disc height and prevents subsidence with a large vertebral body contacting surface area while substantially reducing recovery time by eliminating the need for bridging bone. The intervertebral spacer or fusion spacer includes a rigid spacer body sized and shaped to fit within an intervertebral space between two vertebral bodies. In one embodiment, the spacer body has two opposed metallic vertebral contacting surfaces, at least one fin extending from each of the vertebral contacting surfaces and configured to be positioned within slots cut into the two vertebral bodies. Holes, if present, cover less than 40 percent of the entire vertebral body contacting surfaces to provide increased bone ongrowth surfaces and to prevent subsidence.

Abstract: An intervertebral disc is provided having an upper plate, a lower plate, and a core. The upper and lower plates include outer vertebral body contacting surfaces which are provided with attachment enhancing features to ensure bone integration. The attachment enhancing features shown include one or more fins, serrations and teeth. An opposite surface of the plates from the vertebral body contacting surfaces is formed with a recess which serves as a bearing surface for the core. In order to form an intervertebral disc with a lower disc height, at least one of the recesses is provided opposite a corresponding dome shaped portion on the vertebral body contacting surfaces. This allows the plates to be formed with a thinner profile for a smaller overall disc height. In addition to providing a lower overall height to the artificial disc, the dome shaped portion of the plates also provides a more anatomically shaped outer vertebral body contacting surface.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae includes upper and lower prosthesis plates locatable against respective vertebrae and having opposing, concavely curved recesses therein, and a core located between the plates. The core has opposed, convexly curved surfaces received in the recesses of the plates to allow the plates to slide in articulated manner over the core. The opposed surfaces of the core and the recesses of the plates have cooperating spherical curvatures. The recess of each plate surrounds a locating peg projecting centrally from the base of the recess and is bounded by an annular rim, such that the annular rims of the plates are arranged to contact one another at a predetermined limit of sliding movement of the plates over the core. The peg locates loosely in an opening located centrally in a curved surface of the core, whereby the plates can slide over the core in all directions while the peg holds the core captive.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae includes an upper plate, a lower plate and a core. The core is retained between the upper and lower plates by a retention feature in the form of central projections on the plates and a corresponding opening in the core. The retention feature is designed to allow the plates to slide over the upper and lower surfaces of the core in the anterior/posterior direction and in the lateral direction and to allow the plates to rotate with respect to each other and the core. The retention feature is also designed to prevent contact between the first and second plates during sliding movement of the plates over the core.

Abstract: A prosthetic intervertebral disc is formed of first and second end plates sized and shaped to fit within an intervertebral space and to be implanted from the back of the patient, thereby decreasing the invasiveness of the procedure. The posterior approach provides for a smaller posterior surgical incision and avoids important blood vessels located anterior to the spine particularly for lumbar disc replacements. The first and second plates are each formed of first, second and third parts are arranged in a first configuration in which the parts are axially aligned to form a low profile device appropriate for insertion through the small opening available in the TLIF or PLIF approaches described above. The three parts of both of the plates rotate and translate with respect to one another in situ to a second configuration or a deployed configuration in which the parts are axially unaligned with each other to provide a maximum coverage of the vertebral end plates for a minimum of insertion profile.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae includes upper and lower prosthesis plates locatable against respective vertebrae and having opposing, concavely curved recesses therein, and a core located between the plates. The core has opposed, convexly curved surfaces received in the recesses of the plates to allow the plates to slide in articulated manner over the core. The opposed surfaces of the core and the recesses of the plates have cooperating spherical curvatures. The recess of each plate surrounds a locating peg projecting centrally from the base of the recess and is bounded by an annular rim, such that the annular rims of the plates are arranged to contact one another at a predetermined limit of sliding movement of the plates over the core. The peg locates loosely in an opening located centrally in a curved surface of the core, whereby the plates can slide over the core in all directions while the peg holds the core captive.

Abstract: A prosthesis system comprises plates that can be positioned against vertebrae and a selected resilient core that can be positioned between the plates to allow the plates to articulate. The selected resilient core can be chosen from a plurality of cores in response to patient characteristics, such as age and/or intervertebral mobility, such that the prosthesis implanted in the patient is tailored to the needs of the patient. The plurality of cores may comprise cores with different resiliencies, and one of the cores can be selected such that the upper and lower plates articulate with the desired shock absorbing resiliency and/or maximum angle of inclination when the one selected core is positioned between the plates.

Abstract: An intervertebral prosthetic disc placement instrument is provided for implantation of an intervertebral prosthetic disc. The placement instrument shaft has a distal end and a proximal end and an instrument handle on the proximal end having an activation mechanism. A pair of grasping jaws on the distal end of the instrument shaft are configured to move with respect to one another to grasp a multipart prosthetic disc in a non-articulating configuration. The grasping jaws are movable from a tightened to a released position by the activation mechanism. A prosthetic disc ejector on the distal end of the instrument shaft moves distally with respect to the pair of grasping jaws when the grasping jaws are in the released position and the ejector is configured to contact the prosthetic disc to fully disengage the prosthetic disc from the placement instrument.