Abstract: An intervertebral implant for implantation between an upper vertebra and a lower vertebra having a central axis. The implant may have a first member with a top surface for contacting at least a portion of the upper vertebra and a bottom surface as well as a second member with a top surface and a bottom surface for contacting at least a portion of the lower vertebra. An elastic spacer may be disposed between the first member and the second member. Contraints may be employed to to limit the amount of lateral movement between the first and second members.

Abstract: A spinal implant apparatus that is an expandable spacer including features to minimize or eliminate spacer cant or offset during and after completing the expansion process. The spacer includes a top component, a base component in engagement with the top component, and an expansion mechanism arranged to change the top component's position with respect to the base component. The mechanism for causing expansion may be a screw, a cam, a wedge or other form of distracting device. In one embodiment, the expandable spacer includes a base component with a set of towers and a top component with a set of corresponding silos, where the towers and silos are configured to minimize or eliminate tilt of the top component as it extends upwardly from the base component. In another embodiment, the spacer may include a stepped arrangement around the perimeter of the top component and the base component for engagement during height expansion with minimal canting or slippage.

Abstract: The present invention relates to an intervertebral disc prosthesis comprising at least three pieces including an upper plate, a lower plate, and a movable core at least in relation to a plate, wherein it also comprises two anatomic adaptation elements of which each has, on one hand, a surface in contact with a surface of a vertebra and, on the other hand, a face of which at least a part has a surface in contact with at least a part of the plate opposite to which the anatomic adaptation element is mounted, the anatomic adaptation elements being fixed onto the plates via fixation means.

Abstract: An expandable implant includes a structural insert to provide a robust connection between an insertion instrument and the expandable implant. The structural insert can be made from a different material than the remainder of the implant to withstand compressive, tensile, shear, and torsional loads which may be present while inserting the implant into a patient. The structural insert may be formed as part of a bottom member of the implant or may be a separate element inserted into the implant body. The structural insert may provide a threaded connection to an insertion instrument. The expandable implant may include a bone graft port in fluid communication with a bone graft opening extending through the implant body.

Abstract: Devices, systems and methods for dynamically stabilizing the spine are provided. The devices include an expandable spacer having an undeployed configuration and a deployed configuration, wherein the spacer has axial and radial dimensions for positioning between the spinous processes of adjacent vertebrae. The systems include one or more spacers and a mechanical actuation means for delivering and deploying the spacer. The methods involve the implantation of one or more spacers within the interspinous space.

Abstract: An elongate inserter has a distal end releasably connected to an expandable interbody fusion device and a proximal end including a trigger actuator. The interbody fusion device comprises a superior endplate and an inferior endplate that are movable in an expansion direction relative to each other in the intradiscal space. The inserter includes a lifting platform and an elevator that define cooperatively engaging ramps and ramps surfaces that upon operation of the trigger actuator cause the superior and inferior endplates to move relatively away from each other. A driver is supported by the inserter for pushing an insert into the expanded device between the superior and inferior endplates.

Abstract: A device for insertion into a spinal (intervertebral or intravertebral) space is expandable from a first circumference to a second circumference through axial compression of segments of the device, particularly once the device has been properly situated within a vertebral space. The interbody/intravertebral body device is characterized by a plurality of axially stacked, individual segments that are provided on a central insertion and deployment rod. Each segment includes a central plate or body to which are pivotally attached plate or leaf structures. Pivoting of the structures provides a collapsed or unexpanded position of the first circumference and an open or expanded position of the second circumference.

Abstract: A device is disclosed for reducing a vertebral compression fracture, comprising a superior end plate and an inferior end plate disposed along a vertical axis. The superior end plate and the inferior end plate are slidably separable in a vertical direction along the vertical axis. An interior chamber is provided in fluid communication with a port extending from an exterior to the interior chamber. The device is deployable within a vertebral body and expandable within the vertebral body by injecting a flowable material into the interior chamber thereby displacing the superior and inferior end plates along the vertical axis.

Abstract: A surgical inserter for use in inserting an implant into a vertebral space may include: (a) a handle; (b) a gripper having one end attached to the handle and a second end having a pair of arms; and (c) a grip activator having an opening that threadingly receives the gripper. The grip activator can be rotated in a first direction with respect to the gripper to cause the arms to move toward each other to grip the inserter and in a second direction with respect to the gripper to cause the arms to move away from each other to release the inserter. In one embodiment a compression force activator is used to deploy the implant and in another embodiment a tension force activator is used to deploy the implant.

Abstract: Some embodiments of the invention provide an apparatus that (1) delivers a fusion member between two vertebral bodies after at least a portion of the fibrocartilaginous disc between the vertebral bodies has been removed, and (2) affixes the fusion member to the vertebral bodies. In some embodiments, the apparatus includes (1) a fusion member that is delivered and positioned between the vertebral bodies, (2) a delivery mechanism that delivers and positions the fusion member between the vertebral bodies, and (3) an anchoring member that affixes the fusion member to the vertebral bodies.

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: The present invention relates to an expandable prosthetic implant device for engagement between vertebrae generally comprising an inner member, outer member, and gear member positioned coaxial with respect to each other such that the inner and outer members are moveable relative to each other along an axis. The gear member is axially fixed to the outer member and freely rotatable with respect to the outer member and the gear member threadedly engages a threaded portion of the inner member to translate inner member along the axis. The implant is configured to engage the vertebrae in a predetermined alignment and the gear member includes gear teeth exposed to the exterior and configured to be accessible by a tool member at a plurality of angular positions around the perimeter of the implant device.

Abstract: This invention concerns a vertebral body replacement element to be inserted into an intervertebral space, thus supporting the spinal column of a patient. The vertebral body replacement element has a hollow upper member and a hollow lower member, with the upper member and lower member engaging in a telescopic manner and establishing a cavity between the two members when assembled. Spacers may be inserted in the cavity to lengthen the vertebral body replacement element. The present invention further concerns a system and method for expanding and distracting a vertebral body replacement element into and within the spinal column of a patient.

Abstract: A four-component artificial intervertebral disc may provide six degrees of movement: flexion, extension, lateral bending, axial rotation, axial deflection, and anterior/posterior translation. The disc may include a superior endplate, a superior core, an inferior core, and an inferior endplate. The superior endplate may include a concave mating surface, and the inferior endplate may include a spherical mating surface. The superior endplate may roll across the superior core to provide flexion, extension, and lateral bending. The superior endplate may twist or rotate atop the superior core to provide axial rotation, and the superior endplate may slide over the superior core to provide anterior/posterior translation. The superior core may be connected to the inferior core, and the inferior core may be connected to the inferior endplate. The inferior core may be made from a flexible material that may enable the artificial disc to expand or compress vertically.

Abstract: Intervertebral devices and systems, and methods of their use, are disclosed having configurations suitable for placement between two adjacent vertebrae, replacing the functionality of the disc therebetween. Intervertebral devices and systems contemplated herein are implantable devices intended for replacement of a vertebral disc, which may have deteriorated due to disease for example. The intervertebral devices and systems are configured to allow for ample placement of therapeutic agents therein, including bone growth enhancement material, which may lead to better fusion between adjacent vertebral bones. The intervertebral devices and systems are configured for use in minimally invasive procedures, if desired.

Abstract: An intervertebral prosthesis for insertion between adjacent vertebrae, in one embodiment, includes upper and lower prosthesis plates and a movable core. The prosthesis plates and optionally the core are formed of polyaryletherketone (PAEK) for improved imaging properties. A metallic insert is provided on each of the PAEK prosthesis plates providing a bone ongrowth surface.

Abstract: An endplate for an intervertebral prosthesis includes a generally planar base plate, a first elevated region, or dome, within the base plate periphery, and a second elevated region, or dome, within the boundary of the first elevated region. The antero-posterior and side-to-side (medial-lateral) dimensions of the first elevated region are made to be unequal in order to provide resistance to torsional stresses, and the laterally opposite sidewalls of the first elevated region are defined by arcs that terminate in sagittal planes of the endplate, and are symmetrical with respect to a coronal plane of the endplate. A bone rasp and a groove cutter for use in implanting the prosthesis are also provided.

Abstract: An implant having a base with a first contact surface and a hinged element, hingedly interconnected with a first portion of the base, providing a second contact surface. The first portion of the base is displaceable relative to a second portion so that the base can be shortened from an initial length towards a second length. A linking segment is hingedly connected to both the second portion of the base and to the hinged element so that shortening of the base causes the linking segment to push a region of the hinged element away from the base, thereby changing an angle of the second contact surface relative to the first contact surface.

Abstract: An expandable implant device (100) for insertion between two vertebrae (400) is disclosed. The device (100) has an upper body (20), a lower body (40) and an external retainer band (60). The external retainer band (60) holds the upper body (20) and lower body (40) and has an inner surface having a plurality or set of upper ratchet teeth (80U) sloped for allowing upward movement and a plurality or set of lower ratchet teeth (80L) for allowing downward movement. The ratchet teeth (80) of the upper body (20) are mated or fitted to the upper teeth (80) of the retainer band (60) and the ratchet teeth (82) of the lower body (40) are mated or fitted to the lower ratchet teeth (82) of the retainer band (60). The height of the device (100) is increased by upward movement of the upper body (20) and downward movement of the lower body (40).

Abstract: An expandable anterior lumbar interbody fusion device comprises a deformable monolithic body having posterior and anterior ends, an upper bone contact structure and a lower bone contact structure. The body is expandable along a height axis between a first smaller height to a second larger height. The body comprises a pair of opposed side structures, each including a translatable center section being movable in a direction transverse to the height axis, a first locator arm adjacent the posterior end, a second locator arm adjacent the anterior end and a pair of formable load-bearing columns supported by the upper bone contact structure, the lower bone contact structure and the center section. The columns are not formed at the first height but are operative upon expansion of the body to the second height to form load-bearing columns along the height axis between the upper and lower bone contact structures.

Abstract: Prosthetic intervertebral discs and methods for using the same are described. The subject prosthetic discs include upper and lower endplates separated by a compressible core member. The prosthetic discs described herein include one-piece, two-piece, three-piece, and four-piece structures. The subject prosthetic discs exhibit stiffness in the vertical direction, torsional stiffness, bending stiffness in the sagittal plane, and bending stiffness in the front plane, where the degree of these features can be controlled independently by adjusting the components of the discs. The interface mechanism between the endplates and the core members of several embodiments of the described prosthetic discs enables a very easy surgical operation for implantation.

Abstract: An expandable intervertebral implant is provided for insertion into an intervertebral space defined by adjacent vertebrae. The expandable intervertebral implant includes a pair of outer sleeve portions and an inner core disposed between the outer sleeve portions. Movement of the inner core relative to the outer sleeve portions causes the outers sleeve portions to deflect away from each other, thereby engaging the expandable intervertebral implant with the vertebrae and adjusting the height of the intervertebral space.

Abstract: An expandable implant for inserting within a skeletal space is provided, and a method for using the implant to expand the skeletal space. The implant is preferably designed to be inserted into an intervertebral space to replace at least part of an intervertebral disc between adjacent vertebral bodies. The expandable implant contains at least one first expansion compartment and at least one second expansion compartments, which compartments can be inflatable balloons that are inflated by a catheter. Inflating the first expansion compartment expands the implant in a first direction and inflating the second expansion compartment expands the implant in a second direction.

Abstract: An expandable intervertebral implant (10) includes a first member (20), a second member (40), and a collar operatively associated with the first and second members, wherein the collar includes a threaded mechanism so that rotation of the collar causes the second member to axially move with respect to the first member. The implant includes a ratchet mechanism (50, 80) so that when at least a predetermined amount of force is applied, the second member moves with respect to the first member in an axial, ratchet-type manner. The collar preferably includes a drive ring (60) rotatably attached to the first member and a ratchet ring (80) operatively associated with the drive ring. The ratchet ring includes an inner bore having at least one corresponding ratchet thread tooth form formed thereon for engaging a ratchet thread tooth form formed on the second member.

Abstract: Improved methods and apparatuses for vertebral body distraction and fusion in accordance with various embodiments of the present invention employ one or more coaxial screw gear sleeve mechanisms. In various embodiments, coaxial screw gear sleeve mechanisms include a post with a threaded exterior surface and a corresponding sleeve configured to surround the post, the corresponding sleeve having a threaded interior surface configured to interface with the threaded exterior surface of the post and a geared exterior surface. A drive mechanism can be configured to interface with the geared exterior surface of the sleeve, causing the device to distract.

Abstract: Systems and methods for distracting an intervertebral disc space are provided. The systems use a staged, bilaterally expandable trial. The systems and methods of distracting an intervertebral space are provided in a manner that addresses the problem of subsidence. The method includes inserting the trial into the intervertebral space in a collapsed state and, once inserted, the trial is then used for distracting the intervertebral space using an expansion that includes a first stage and a second stage. The first stage includes expanding the trial laterally toward the peripheral zones of the top vertebral plate and the bottom vertebral plate, and the second stage includes expanding the trial vertically to distract the intervertebral space.

Abstract: The subject disclosure is directed to systems, apparatuses, devices and methods for vertebral and spinal correction. In some embodiments, an expandable implant is provided which may be inserted inside the vertebral body and/or between two vertebrae, for instance, for maintenance and/or restoration of a space therein or there between. In certain embodiments, the implant includes a mechanical resistance that prevents the expandable implant from contracting once it has been expanded. Methods of treatment and methods of use of such implants for the alleviation of back pain (for example) are also provided herein.

Abstract: An expandable interbody fusion device includes superior and inferior endplates that are configured to receive a sequentially inserted stack of expansion members or wafers in interlocking engagement. The expansion members are formed to each have a generally U-shaped rearward facing opening. The superior and inferior endplates have openings through their outer surfaces in at least partial alignment and communication with the rearward facing openings of the expansion members. The inferior endplate has a fully bounded cavity for telescoping receipt of the superior endplate. The inferior endplate also has a fully bounded channel extending through the rear endwall thereof in direct communication with the rearward facing opening of at least one expansion member for the receipt of bone graft material into the device to promote fusion between opposing vertebral bodies of the spine.

Abstract: An intervertebral implant includes first and second implant bodies, which extend along a longitudinal direction of the implant, and a threaded member. The bodies include first and second proximal and distal ends movable longitudinally relative to each other. The threaded member is rotatably seated in the first implant body and has a proximal end accessible from outside the implant.

Abstract: An expandable interbody fusion device includes superior and inferior endplates that are configured to receive a sequentially inserted stack of interlocking expansion members or wafers. The like-configured wafers include features on their top and bottom surfaces that interlock the wafers in multiple degrees of freedom so that the wafer stack is not disrupted when the fusion device is fully expanded. One of the interlocking features includes a plurality of prongs projecting from an upper surface of the wafers and into a recess defined in the lower surface of an adjacent previously inserted like-configured wafer. The prongs and recesses are configured to prevent retrograde movement of each new wafer in a direction opposite the direction of insertion. Other interlocking features prevent movement in the direction of insertion, transverse to the insertion direction and vertically within the stack.

Abstract: Systems and methods for distracting an intervertebral disc space are provided. The systems use a staged, bilaterally expandable trial. The systems and methods of distracting an intervertebral space are provided in a manner that addresses the problem of subsidence. The method includes inserting the trial into the intervertebral space in a collapsed state and, once inserted, the trial is then used for distracting the intervertebral space using an expansion that includes a first stage and a second stage. The first stage includes expanding the trial laterally toward the peripheral zones of the top vertebral plate and the bottom vertebral plate, and the second stage includes expanding the trial vertically to distract the intervertebral space.

Abstract: The present invention relates to an intervertebral disc prosthesis preferably comprising at least three pieces including an upper plate (1), a lower plate (2) and a mobile core (3) at least in relation to the lower plate (2), co-operation means (23, 33) allowing to limit or eliminate the movements of the core (3) in relation to the lower plate (2), in translation and in rotation, respectively, about an axis substantially parallel to the lower plate (2) and about an axis substantially perpendicular to the lower plate (2), at least one part of the surface of at least one plate being concave and complementary with a convex surface (30) of the core (3), with which it is in contact, wherein the tip (31) of the convex surface (30) of the core (3) is off center, in at least one direction, in relation to the center (32) of this convex surface (30).

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: An intervertebral implant comprises first and second parts having outer surfaces engaging adjacent vertebral surfaces. An insert between these parts provides relative movement therebetween. The first and/or second parts may have engagement means in the form of apertures for engagement with insertion instruments. The first and second parts may nest together, in the absence of the insert, for insertion into the intervertebral space. The boundaries of the implant may form a working space which would include insertion instruments therein. A detent and detent recess may be provided for engagement of the insert and one of said first and second parts.

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: An expandable housing for an interbody fusion system has movable tapered external helical threaded members that travel along tracking to operably engage against the top and bottom shell members, urging them apart to cause expansion in the height of the housing. In an embodiment, the tapered members are disposed in a dual arrangement such that independent engagement of the tapered members along lateral portions of the top and bottom shells cause an angular tilt to the exterior surface of the housing when the tapered members are moved to different degrees. This function permits adjustment in the angular relationship between adjacent vertebrae and assists the lordotic adjustment of the patient's spine. When the functions of the device are used in combination by the surgeon, the device provides an effective tool for in situ adjustment when performing lateral lumbar interbody fusion.

Abstract: An expandable spinal implant configured for positioning within a space between adjacent vertebral bodies includes an upper body, a lower body, and first and second pins. The lower body is adapted to slidably receive the upper body. Grooves are disposed on opposing side surfaces of the upper body, and grooves are disposed on an inner surface of a bore defined through the lower body. Corresponding first and second apertures are defined through an end surface of the lower body thereby permitting advancement of the first and second pins within the first and second apertures, grooves of the lower body, and a corresponding pair of grooves of the upper body to secure the position of the upper body relative to the lower body. A method of performing spinal surgery is also disclosed.

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 spinal implant which is configured to be deployed between adjacent vertebral bodies. The implant has at least one extendable support element with a retracted configuration to facilitate deployment of the implant and an extended configuration so as to expand the implant and effectively distract the disc space, stabilize the motion segments and eliminate pathologic spine motion. Angular deformities can also be corrected, and natural curvatures restored. Preferably, the implant has a minimal dimension in its unexpanded state that is smaller than the dimensions of the neuroforamen through which it typically passes to be deployed within the intervertebral space. The implant is provided with a locking system preferably having a plurality of locking elements to lock the implant in an extended configuration. Bone engaging anchors also may be provided to ensure secure positioning.

Abstract: An intervertebral disc prosthesis comprises a structure having a rigid upper plate, a rigid lower plate, and a core inserted between said plates, the structure being made from thermoplastic material, the core further comprising a thermoplastic monomaterial having graduated elastic and damping properties. According to one alternative, the core is composed of an elastomeric central nucleus surrounded by one or more rings which are referred to as rings having ranks j relative to the core, and which are more rigid.

Abstract: An intervertebral implant that can be surgically introduced between adjacent vertebrae and expanded in situ to occupy an optimal space between the vertebrae. The implant is inserted into the evacuated disc space obliquely and then oriented so as to extend laterally across the anterior adjacent vertebrae with its outer ends of the implant supported by the cortical rims on the opposite sides of the vertebrae. The implant has two body members with a space therebetween so the implant may be then distracted and a spacer of predetermined thickness that may be inserted within the space between the body members so as to maintain a desired amount of distraction. The upper and lower surfaces of the implant may have a desired lordotic angle. A method of using an implant is disclosed which permits endoscopic visualization of the disc space.

Abstract: An artificial disc is disclosed. The artificial disc may include a superior endplate having a bi-convex superior surface and a concave inferior surface, and an inferior endplate having a bi-convex inferior surface. The artificial disc may also include a core assembly disposed between the superior endplate and the inferior endplate, and a support assembly disposed on outer surfaces of both the superior endplate and the inferior endplate. The support assembly may be configured to couple the superior endplate to the inferior endplate.

Abstract: The present invention provides artificial disc prostheses, methods and instrumentation for implantation and revision thereof. Each prosthesis may comprise superior and inferior end plates and a nucleus positioned between articular surfaces of the end plates. The end plates may have planar bone engagement surfaces with a plurality of self-cutting teeth. The articular surfaces of the end plates may be planar or include a flattened portion. The nucleus includes superior and inferior articular surfaces which may comprise flattened portions such that when the articular surfaces of the nucleus and the end plates are placed in cooperation in a preferred orientation, the flattened and/or planar portions are aligned. Each prosthesis may provide flexion/extension, anterior/posterior translation, lateral bending, and/or axial rotation degrees of freedom.

Abstract: This disclosure relates to an intervertebral disc prostheses that comprise at least three pieces including an upper plate, a lower plate, and a mobile core, the upper surface of the core being in contact with at least a part of the lower surface of the upper plate, limit stops allowing friction to be limited, while limiting or preventing the movements of the core relative to the lower plate, in translation and in rotation, respectively, along an axis substantially parallel to the lower plate and about an axis substantially perpendicular to the lower plate. Instrumentation for insertion of the prostheses into intervertebral spaces is also described.

Abstract: An expandable intervertebral cage adapted to be implanted into an intervertebral disc space in a patient's body, the expandable intervertebral cage including first and second base plates having outer surfaces configured to interface with vertebra in the intervertebral disc space, a first, second and third arm assembly hingedly connected to first and second base plates, and first and second actuation members, wherein rotation of the first actuation member pulls the second arm assembly towards the first arm assembly and rotation of the second actuation member pulls the third arm assembly towards the second arm assembly, the first actuation member and the second actuation member capable of being actuated independently of each other.

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: A stabilization system for a human spine is provided. The stabilization system may include two dynamic interbody devices and/or one or more dynamic posterior stabilization systems. The dynamic interbody devices may be inserted into a disc space using a posterior approach. The dynamic interbody devices may allow for coupled axial rotation and lateral bending of vertebrae adjacent to the dynamic interbody devices. The dynamic posterior stabilization systems may provide resistance to movement that mimics the resistance provided by a normal functional spinal unit.

Abstract: A device for insertion into a spinal (intervertebral or intravertebral) space is expandable from a first circumference to a second circumference through axial compression of segments of the device, particularly once the device has been properly situated within a vertebral space. The interbody/intravertebral body device is characterized by a plurality of axially stacked, individual segments that are provided on a central insertion and deployment rod. Each segment includes a central plate or body to which are pivotally attached plate or leaf structures. Pivoting of the structures provides a collapsed or unexpanded position of the first circumference and an open or expanded position of the second circumference.

Abstract: An expandable implant for engagement between vertebrae includes an inner member, an outer member, and a gear member positioned coaxial with respect to each other such that the inner and outer members are moveable relative to each other along an axis. The inner member includes a longitudinal groove configured to engage a pin extending through the outer member such that the pin prevents the inner member from translating completely through the outer member and aids in alignment and limits rotation of the second endplate. Portions of the implant may be provided with a series of markings such that when the markings are aligned, the implant is aligned in a specific configuration and for a specific implantation approach.

Abstract: The invention relates to an expandable implant (11) with an upper plate (12) and a lower plate (16) which extend in the xy plane, which serve for anchoring on/in the vertebral support surfaces, and at least three gears (20, 25, 30) which are coupled to each other, wherein the gears (20, 25, 30) serve to expand the implant (11), and each gear (20, 25, 30) has a threaded spindle (21, 25, 31) and a threaded sleeve with corresponding inner thread (22, 27, 32), wherein the pitch of one thread (31, 32) is different from the pitch of the other threads (21, 22; 26, 27). The invention also relates to an operating instrument (80) for this implant.