Intervertebral prosthetic disc placement and removal systems

A method of removing a core from an intervertebral prosthetic disc, the method comprising:

• securing a multipart prosthetic disc to a distal end of a removal instrument by grasping at least a portion of the multipart prosthetic disc between a pair of core removal arms on the placement instrument, wherein the arms are each tapered from a thinnest portion at their distal ends to a thicker portion at some distance from the distal end;
• inserting the pair of core removal arms between two prosthetic disc plates of the intervertebral prosthetic disc to distract the plates away from one another;
• and
• removing the core from the intervertebral prosthetic disc with the removal instrument, the removal instrument including:
• a pair of distraction wedges, each wedge being tapered from a thinnest portion at a distal end of a respective one of the pair of core removal arms to a thicker portion at some distance from the distal end, the thicker portion extending outward along an axis perpendicular to an axial orientation of the pair of removal arms;
• and
• a core removal instrument handle connected to the pair of core removal arms and the distraction wedge, the handle configured to move the arms with respect to one another to grasp the core for removal and configured to advance the distraction wedge from a distal end of the core removal handle to allow the core to be removed.

A system for removing a core from an intervertebral prosthetic disc, the system comprising:

• a core removal instrument including:
• a pair of core removal arms having inner surfaces shaped to correspond substantially to a shape of an outer perimeter of a prosthetic disc core, wherein the arms are each tapered from a thinnest portion at their distal ends to a thicker portion at some distance from the distal end such that insertion of the arms between two prosthetic disc plates distracts the plates away from one another to allow the core to be removed;
• and
• an inner shaft connected to the pair of core removal arms;
• an outer shaft movable with respect to the inner shaft and including an activation mechanism for causing the arms to grasp the core for removal, the outer shaft having an axial channel shaped to slidably engage an outer surface of the pair of core removal arms at the thicker portion thereof, such that the pair of core removal arms are selectively seated within the outer shaft;
• and
• a prosthetic disc comprising:
• an upper plate and a lower plate, wherein the upper and lower plates are configured to articulate with respect to one another and wherein the pair of core removal arms are configured to grasp the upper and lower plates in the non-articulating configuration.

A system for removing a core from an intervertebral prosthetic disc, the system comprising:

• a core removal instrument including:
• a pair of core removal arms having inner surfaces shaped to correspond substantially to a shape of an outer perimeter of a prosthetic disc core;
• a pair of distraction wedges, each wedge being tapered from a thinnest portion at a distal end of a respective one of the pair of core removal arms to a thicker portion at some distance from the distal end, the thicker portion extending outward along an axis perpendicular to an axial orientation of the pair of removal arms, such that insertion of the distraction wedge between two prosthetic disc plates of the prosthetic disc distracts the plates away from one another to allow the core to be removed;
• and
• a core removal instrument handle connected to the pair of core removal arms and the distraction wedge, the handle configured to move the arms with respect to one another to grasp the core for removal and configured to advance the distraction wedge from a distal end of the core removal handle and distract the plates away from one another to allow the core to be removed;
• and
• a prosthetic disc comprising:
• an upper plate and a lower plate, wherein the upper and lower plates are configured to articulate with respect to one another and wherein the pair of core removal arms are configured to grasp the upper and lower plates in the non-articulating configuration.