Expandable intervertebral implant

Abstract

The intervertebral implant is configured to be implanted into an intervertebral space in a first initial configuration, and the actuator is then configured to be driven in an actuation direction to expand the implant along a first expansion direction, and once the implant is fully expanded along the first expansion direction, the actuator is further configured to be driven in the actuation direction to expand the implant in a second expansion direction perpendicular to the first expansion direction.

Description

Technical Field

[0002]

[0001] The present disclosure relates to implantable devices for orthopedics, and more particularly, to implantable devices for stabilizing the spine. Even more particularly, the present disclosure relates to an expandable and angle-adjustable intervertebral cage having a joint mechanism that enables expansion from a first insertion configuration having a reduced size to a second implanted configuration having an expanded size. The intervertebral cage is configured to adjust and conform to a lordotic angle, particularly a greater lordotic angle, while restoring the sagittal balance and alignment of the spine.

Background Art

[0002] Often, the use of implantable devices for promoting fixation between vertebral bodies, referred to as cages or spacers, is well known as a standard of care for the treatment of certain spinal disorders or diseases. For example, in one type of spinal disorder, the intervertebral disc is deteriorated or damaged due to acute injury or trauma, intervertebral disc disease, or simply the natural aging process. A healthy intervertebral disc serves to stabilize the spine, disperse the forces between vertebrae, and protect the vertebral bodies. Therefore, a weakened or damaged intervertebral disc causes an imbalance and destabilization of the forces in the spine, resulting in discomfort and pain. Typical treatments may involve surgically removing a portion or all of the diseased or damaged intervertebral disc in a process known as partial or total discectomy, respectively. Discectomy often follows the insertion of a cage or spacer to stabilize this weakened or damaged spinal region. This cage or spacer serves to reduce or suppress the mobility of the treated area to avoid further progression of the injury and / or to reduce or relieve the pain caused by the injury or trauma. Further, these types of cages or spacers function as a mechanical or structural scaffold for restoring and maintaining normal intervertebral disc height and, in some cases, may also promote bone fixation between adjacent vertebrae.

[0003] However, one of the current challenges of these types of procedures is the extremely limited working space given to the surgeon to manipulate and insert the cage within the intervertebral space being treated. Access to the intervertebral space requires navigation around constricted adjacent blood vessels and tissues such as the aorta, vena cava, dura mater, and nerve roots, leaving a very narrow pathway for access. The opening into the intervertebral space itself is also relatively small. Thus, there are physical limitations on the actual size of the cage that can be inserted without significantly damaging the surrounding tissue or the vertebral body itself.

[0004] Further complicating the problem is the fact that the vertebral bodies are not positioned parallel to each other within a normal spine. The natural curvature of the spine is due to the relative angles of the vertebral bodies. An ideal cage must be able to adapt to these angles, or the cage will not seat properly when it is inside the intervertebral space. An improperly fitted cage will become dislodged or shift, losing its effectiveness over time or further damaging already weakened areas. [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Therefore, it is desirable to provide an intervertebral cage or spacer that not only has the mechanical strength or structural integrity to restore the height of the intervertebral disc or vertebral alignment to the spinal segment being treated, but also easily passes through a narrow access path into the intervertebral space and is then configured to adapt to the angular constraints of this intervertebral space, particularly for larger lordosis angles. [Means for solving the problem]

[0006] In one example, an intervertebral implant may include an implant body defining an upper body configured to face the superior vertebra and a lower body configured to face the inferior vertebra. The implant may further include an actuator supported by the implant body, the actuator being movable within the implant body from an initial position to a first expansion position, and subsequently movable from the first expansion position to a second expansion position. Movement of the actuator from the initial position to the first expansion position causes the actuator to expand the implant body along a first expansion direction, and movement of the actuator from the first expansion position to the second expansion position causes the actuator to expand the implant body along a second expansion direction perpendicular to the first expansion direction.

[0007] The actuator may be able to translate from an initial position to a first extended position. The actuator may be able to translate further from the first extended position to a second extended position.

[0008] The actuator may be capable of distal translation from an initial position to a first extended position. The actuator may be capable of further distal translation from the first extended position to a second extended position.

[0009] The first expansion direction may be perpendicular to the distal direction. The second expansion direction may be perpendicular to both the distal direction and the first direction.

[0010] The actuator may define a head that expands the implant body along first and second expansion directions.

[0011] In some cases, the movement of the actuator from the initial position to the first expansion position does not expand the implant body along the second expansion direction.

[0012] In some cases, the movement of the actuator from the first expansion position to the second expansion position does not expand the implant body along the first expansion direction.

[0013] The first expansion direction may cause each of the upper and lower bodies to expand. The second expansion direction may cause at least one of the upper and lower bodies to move away from the other.

[0014] In some examples of intervertebral implants, 1) the implant body may define opposing inclined medial surfaces and inclined upper and lower surfaces, with at least each portion of the inclined medial upper and lower surfaces being distally separated from the inclined medial surface; 2) the actuator may ride up along the inclined medial surface to expand the implant body along a first expansion direction; and 3) the actuator may ride up along the inclined upper and lower surfaces to expand the implant body along a second expansion direction.

[0015] The inner upper and lower surfaces of the incline may be stepped.

[0016] The actuator may comprise a shaft portion and an expansion head that can extend from the shaft portion along both first and second expansion directions. The expansion head can expand the implant body along the first and second expansion directions.

[0017] The expansion of the implant body along the second expansion direction can change the lordosis angle defined by the outer upper surface of the upper body and the outer lower surface of the lower body.

[0018] Expansion of the implant body along the second expansion direction can increase the lordosis angle.

[0019] The implant body may comprise a frame including a base and upper and lower body portions that extend distally from the base.

[0020] The upper and lower body can bend around the base as the implant body expands along the second expansion direction.

[0021] In some examples of intervertebral implants, 1) the upper body may comprise a first upper body portion, a second upper body portion, and an upper expandable mesh that can connect the first upper body portion to the second upper body portion, and 2) the lower body portion may comprise a first lower body portion, a second lower body portion, and a lower expandable mesh that can connect the first lower body portion to the second lower body portion.

[0022] The expansion of the implant body along the first expansion direction may involve 1) moving at least one of the first and second upper body portions away from the other of the first and second upper body portions, and 2) moving at least one of the first and second lower body portions away from the other of the first and second lower body portions.

[0023] The upper mesh may expand as at least one of the first and second upper body parts moves away from the other. The lower mesh may expand as at least one of the first and second lower body parts moves away from the other.

[0024] The intervertebral implant may further comprise an expandable first lateral mesh connecting a first upper body portion to a first lower body portion. The intervertebral implant may further comprise an expandable second lateral mesh connecting a second upper body portion to a second lower body portion. The first and second lateral meshes may expand as the implant body expands along a second direction. [Brief explanation of the drawing]

[0025] The above summary, as well as the following detailed description of exemplary embodiments of this application, will be better understood when read in conjunction with the accompanying drawings. Exemplary embodiments are shown in the drawings for the purpose of illustrating the locking structures of this application. However, it should be understood that this application is not limited to the exact arrangements and means shown. [Figure 1A] The image shows a pair of intervertebral implants inserted into the intervertebral space of the first insertion configuration. [Figure 1B] Shows the intervertebral implant of FIG. 1A extended along the first expansion direction. [Figure 1C] Shows the intervertebral implant of FIG. 1B further extended along the second expansion direction. [Figure 2A] It is a first perspective view of the implant body of a pair of intervertebral implants illustrated in FIG. 1A. [Figure 2B] It is a second perspective view of the implant body illustrated in FIG. 2A. [Figure 3A] It is an exploded perspective view of one of the pair of intervertebral implants illustrated in FIG. 1A. [Figure 3B] It is a cross-sectional perspective view of the intervertebral implant illustrated in FIG. 3A. [Figure 3C] It is an exploded cross-sectional side elevation view of the intervertebral implant illustrated in FIG. 3A. [Figure 4A] It is a cross-sectional side elevation view of the intervertebral implant illustrated in FIG. 3A, showing the implant in the first or initial configuration. [Figure 4B] It is a cross-sectional side elevation view of the intervertebral implant of FIG. 4A, showing the implant extended along the first expansion direction. [Figure 5A] It is another cross-sectional side elevation view of the intervertebral implant illustrated in FIG. 4B. [Figure 5B] It is a side elevation view of the intervertebral implant illustrated in FIG. 5A, showing the implant extended along the second expansion direction. [Figure 5C] It is a side elevation view of the intervertebral implant illustrated in FIG. 5B, showing the implant further extended along the second expansion direction. [Figure 6A] Shows a lock assembly configured according to an embodiment. It is an exploded perspective view of a part of the intervertebral implant of FIG. 3A. [Figure 6B] It is an exploded perspective view of a part of the intervertebral implant of FIG. 6A, showing the lock assembly in the locked configuration.

BEST MODE FOR CARRYING OUT THE INVENTION

[0026] This disclosure provides various spinal or intervertebral implants, such as intervertebral stabilization spacers or cages, for insertion between adjacent vertebrae. The devices may be configured for use in either the cervical or lumbar region of the spine. In some embodiments, these devices are configured as PLIF cages or posterior lumbar intervertebral stabilization cages. These cages can stabilize the spine by restoring and maintaining intervertebral height in the spinal segment being treated and by restoring sagittal balance and alignment. In some embodiments, the cages may include articulation mechanisms to allow expansion and angle adjustment. These articulation mechanisms allow upper and lower plate components to slide smoothly against each other.

[0027] As shown in Figure 1A, one or more intervertebral implants 20 can be inserted into the intervertebral space 22 in a first insertion configuration featuring a first reduced-size insertion end to facilitate insertion through a narrow access passage. One or more intervertebral implants 20 can be inserted into the intervertebral space using a PLIF approach. However, it is recognized that one or more intervertebral implants 20 can be inserted along any preferred approach as needed. Although a pair of intervertebral implants 20 inserted into the intervertebral space is shown, it is also recognized that a single implant can be inserted into an intervertebral space of any preferred size and shape as desired. The intervertebral space 22 is defined by the superior and inferior vertebrae 24 and 26, which are spaced apart from each other along a transverse direction T that defines the craniocaudal direction when the intervertebral implants 20 are positioned within the intervertebral space 22. Structures, elements, devices, and method steps described in the plural as described herein are applied in the singular with equal force and effect unless otherwise indicated. For example, although a pair of intervertebral implants 20 are shown implanted in the intervertebral space 22 in Figure 1A, it is recognized that a single intervertebral implant 20 can be implanted in the intervertebral space 22 instead. Conversely, structures, elements, devices, and method steps described in the singular, as described herein, are applied in the plural with equal force and effect unless otherwise specified.

[0028] The intervertebral implant 20 is inserted with a first reduced size, as shown in Figure 1A, and can then be expanded to a second expanded configuration having an expanded size upon implantation, as shown in Figures 1B and 1C. The second expanded size is larger than the first reduced size in at least one direction. In some embodiments, the second expanded size is larger than the first reduced size along two vertical directions, each perpendicular to the insertion direction. In those second expanded configurations, the cage can stabilize the spine by maintaining appropriate intervertebral disc height and restoring sagittal balance and alignment.

[0029] For example, as shown in Figure 1B, the second expansion configuration may include the first expansion in the lateral direction A, which is oriented perpendicular to the transverse direction T. In particular, the intervertebral implant 20 can expand in the first expansion direction to achieve the first expansion along the lateral direction A. Thus, the first expansion direction can be along the lateral direction A. That is, the implant has a first width along the lateral direction A of the first reduction size, and a second width along the lateral direction A of the second expansion size, which is larger than the first width.

[0030] Furthermore, as shown in Figure 1C, the second expansion configuration may include a second expansion in the transverse direction T. In particular, the intervertebral implant 20 can expand in the second expansion direction to achieve a second expansion along the transverse direction T. Therefore, the second expansion direction can be along the transverse direction T.

[0031] As will be explained in more detail below, the intervertebral implant 20 can expand only along the first expansion direction without expanding in the second expansion direction. Subsequently, the intervertebral implant can expand only along the second expansion direction without expanding in the first expansion direction. In some examples, the implant can expand simultaneously along both the first and second expansion directions after expanding only along the first expansion direction and before expanding only along the second expansion direction. Furthermore, in some examples, the intervertebral implant 20 may be expandable in the second expansion direction only after expansion in the first expansion direction is complete.

[0032] In some embodiments, it is assumed that the intervertebral implant 20 may also be designed to expand in either or both of the first and second expansion directions in a freely selectable (or stepless) manner to reach its second expansion configuration. The intervertebral implant 20 may further be configured to allow adjustment of the lordosis angle, providing a greater lordosis angle in the second expansion configuration. Furthermore, the intervertebral implant 20 may promote fusion to further improve spinal stability by fixing adjacent vertebral bodies.

[0033] In addition, the intervertebral implant 20 may be manufactured using selective laser melting (SLM) technology, a form of additive manufacturing. The intervertebral implant 20 may also be manufactured by other equivalent technologies, such as 3D printing, electron beam melting (EBM), layer deposition, and rapid production. These production technologies make it possible to create a single, multi-component device that may have interconnected movable parts without requiring additional external fixation or attachment elements to hold the components together. Thus, the intervertebral implant 20 disclosed herein may be formed from multiple interconnected parts that do not require additional external fixation elements to hold them together.

[0034] In some examples, the intervertebral implant 20 manufactured in this manner does not have connecting seams, whereas conventionally manufactured devices have joints that connect one component to another. These connecting seams can often represent weakened areas of conventionally manufactured implantable devices, particularly when the joints of these seams wear or break over time under repeated use or stress. By manufacturing the intervertebral implant 20 of the present invention using additive manufacturing, connecting seams are completely avoided, thereby avoiding the problem.

[0035] In addition, by manufacturing the intervertebral implant 20 using an additive manufacturing process, all components of the intervertebral implant 20 (including both the implant body and the actuator configured to expand the implant body as described below) remain as a complete structure during both the insertion and expansion processes. That is, the multiple components of the intervertebral implant 20 are provided together as a single collective unit, so that the single collective unit can be inserted into the patient, actuated to allow expansion, and then remain in place as a single collective unit. In contrast to other implantable implants that require the insertion of a male screw or wedge for expansion, in this embodiment, the actuator does not need to be inserted into or removed from a cage at any stage in the process in some examples. This is because the actuator is manufactured to be trapped inside the implant body and, although freely movable within the cage, is already confined within the implant body, thus eliminating the need for additional insertion or removal of the actuator.

[0036] In some embodiments, the implantable implant 20 may be formed comprising part or all of an engineered cellular structure including pores, microstructures, and nanostructures to facilitate osseointegration. For example, the engineered cellular structure may include interconnected reticular tissue of pores, as well as other micro and nano-sized structures employing a mesh-like appearance. These engineered cellular structures may be provided by etching or blasting to alter the surface of the device at the nanoscale. One type of etching process may utilize, for example, HF acid treatment. In addition, these cages may also include internal imaging markers that allow the user to properly align the implantable implant 20 and generally facilitate insertion through visualization during navigation. The imaging markers are shown, for example, as solids within a mesh under X-ray, fluoroscopy, or CT scans.

[0037] Another benefit offered by the implantable implants 20 of this disclosure is that they can be specifically customized to the needs of a patient. Customization of the implantable implants 20 relates to providing the implant device with a favorable modulus of elasticity that is compatible with various qualities and types of bone being treated, such as cortical versus cancellous, epiphyseal versus cephalic, and sclerosing versus osteopenic bone, each of which has its own different compressions against structural damage data. Similarly, similar data can be generated for various implant designs, such as porous versus solid, trabecular versus non-trabecular. Such data may be from cadavers or generated computer finite elements. Clinical correlation with DEXA data, for example, may also enable the implantable device to be specifically designed for use with sclerosing, normal, or osteopenic bone. Therefore, the ability to provide customized implantable devices, such as those provided herein, enables matching of the Elastic Modulus of Complex Structure (EMOCS), which allows the implantable device to be engineered to minimize mismatch, reduce settlement, optimize healing, and thereby provide better clinical outcomes.

[0038] Referring here to Figures 2A to 3C, the intervertebral implant 20 includes an implant body 28 and an actuator 29 located within the implant body 28. The actuator 29 is configured to drive the implant body 28, and therefore the intervertebral implant 20, to expand from a first insertion configuration to a second expansion configuration. The implant body 28, and therefore the intervertebral implant 20, defines a distal end 30 and a proximal end 32 opposite the distal end 30. Thus, the distal direction is defined as the direction from the proximal end 32 toward the distal end 30. Conversely, the proximal direction is defined as the direction from the distal end toward the proximal end 32. The distal and proximal directions can be oriented along the longitudinal direction L. The longitudinal direction L can be perpendicular to the transverse direction T and the transverse direction A, respectively. The distal end 30 defines the anterior end with respect to the direction of insertion into the intervertebral cavity, and the proximal end 32 defines the posterior end with respect to the direction of insertion into the intervertebral cavity.

[0039] Referring particularly to Figures 2A and 2B, the implant body 28 includes an upper body 34 and a lower body 36 located opposite the upper body 34 along the transverse direction T. The upper body 34 defines an external upper surface 35 configured to abut against the upper vertebra 24, and the lower body 36 defines an external lower surface 37 configured to abut against the lower vertebra 26. In one example, the upper and lower bodies 34 and 36 may define projections in the form of teeth, spikes, or ridges configured to grip the upper and lower bodies 34 and 36 in order to restrict or prevent the movement of the intervertebral implant 20 within the intervertebral space.

[0040] The upper body 34 can be divided into a first upper body portion 34a and a second upper body portion 34b. The first and second upper body portions 34a and 34b can be aligned with each other along the lateral direction A. Furthermore, the first and second upper body portions 34a and 34b can be mirror images of each other. The implant body 28 may include an expandable upper mesh portion 38 extending between the first upper body portion 34a and the second upper body portion 34b. For example, the upper mesh portion 38 can extend from the first upper body portion 34a to the second upper body portion 34b. Thus, the upper mesh portion 38 connects the first upper body portion 34a to the second upper body portion 34b. The upper mesh portion 38 can extend to the distal end of the implant body 28, or it can terminate at a position spaced proximal to the distal end of the implant body 28. The upper mesh portion 38 can be oriented along the lateral direction A. Therefore, as will be described in more detail below, the upper mesh portion 38 is expandable such that, as the intervertebral implant 20 expands along the lateral direction A, one or both of the first and second upper body portions 34a and 34b move away from the other of the first and second upper body portions 34a and 34b.

[0041] The implant body 28 can define a base 40 positioned such that the first and second upper body portions 34a and 34b extend distally from the base 40. The base 40 can define the proximal end 32 of the implant body 28 and can further define an opening configured to receive an operating tool configured to apply an operating force to the actuator 29. The base 40 can be configured as an annular body that extends continuously around the periphery of the implant body 28. Thus, in one example, the base 40 can be located in a plane oriented along the transverse direction T and the lateral direction A. When the intervertebral implant 20 is in the first insertion configuration, the first and second upper body portions 34a and 34b can extend parallel to each other. Furthermore, when the intervertebral implant 20 is in the first insertion configuration, the first and second upper body portions 34a and 34b can be spaced apart from each other by a first distance. Alternatively, when the intervertebral implant 20 is in the first insertion configuration, the first and second upper body portions 34a and 34b can be adjacent to each other.

[0042] The lower body 36 can be divided into a first lower body portion 36a and a second lower body portion 36b. The first and second lower body portions 36a and 36b can be aligned with each other along the transverse direction A. Furthermore, the first and second lower body portions 36a and 36b can be mirror images of each other. The first lower body portion 36a can be aligned with the first upper body portion 34a along the transverse direction T. Similarly, the second lower body portion 36b can be aligned with the second upper body portion 34b along the transverse direction T. The implant body 28 may include an expandable lower mesh portion 42 extending from the first lower body portion 36a and the second lower body portion 36b. For example, the lower mesh portion 42 can extend from the first lower body portion 36a to the second lower body portion 36b. Thus, the lower mesh portion 42 connects the first upper body portion 34a to the second upper body portion 34b. The lower mesh portion 42 can extend further distally from the base 40. The lower mesh portion 42 can extend to the distal end of the implant body 28, or can terminate at a position proximal to the distal end of the implant body 28. The lower mesh portion 42 can be oriented along the transverse direction A. Thus, as will be described in more detail below, the lower mesh portion 42 is expandable to allow one or both of the first and second lower body portions 36a and 36b to move away from the other of the first and second upper body portions 36a and 36b as the intervertebral implant 20 expands along the transverse direction A.

[0043] The first and second lower body portions 36a and 36b can extend distally from the base 40. When the intervertebral implant 20 is in the first insertion configuration, the first and second lower body portions 36a and 36b can extend parallel to each other. Furthermore, when the intervertebral implant 20 is in the first insertion configuration, the first and second lower body portions 36a and 36b can be spaced apart by a first distance. Alternatively, when the intervertebral implant 20 is in the first insertion configuration, the first and second upper body portions 36a and 36b can be adjacent to each other.

[0044] The implant body 28 may further include an expandable first lateral mesh portion 44 extending between the first upper body portion 34a and the first lower body portion 36a. For example, the first lateral mesh portion 44 may extend from the first upper body portion 34a to the first lower body portion 36a. Thus, the first lateral mesh portion 44 connects the first upper body portion 34a to the first upper body portion 34a. The first lateral mesh portion 44 may further extend distally from the base 40. The first lateral mesh portion 44 may extend to the distal end of the implant body 28, or may terminate at a position proximal to the distal end of the implant body 28. The first lateral mesh portion 44 may be oriented substantially in the transverse direction T. Therefore, as will be described in more detail below, the first lateral mesh portion 44 is expandable along the transverse direction T, allowing one or both of the first upper body portion 34a and the first lower body portion 36a to move away from the other of the first upper body portion 34a and the first lower body portion 36a as the intervertebral implant 20 expands along the transverse direction T.

[0045] The implant body 28 may further include an expandable second lateral mesh portion 46 extending between the second upper body portion 34b and the second lower body portion 36b. For example, the second lateral mesh portion 46 may extend from the second upper body portion 34b to the second lower body portion 36b. Thus, the second lateral mesh portion 46 connects the second upper body portion 34b to the second upper body portion 34b. The second lateral mesh portion 46 may further extend distally from the base 40. The second lateral mesh portion 46 may extend to the distal end of the implant body 28, or may terminate at a position proximal to the distal end of the implant body 28. The second lateral mesh portion 46 may be oriented substantially in the transverse direction T. Therefore, as will be described in more detail below, the second lateral mesh portion 46 is expandable along the transverse direction such that, as the intervertebral implant 20 expands along the transverse direction T, one or both of the second upper body portion 34b and the second lower body portion 36b move away from the other of the first upper body portion 34a and the first lower body portion 36a.

[0046] In one example, the implant body 28 can be configured such that the base 40 defines a frame 48 in combination with first and second upper body portions 34a-34b and first and second lower body portions 36a-36b. Thus, the implant body 28 can include a frame 48 and mesh portions 38, 42, 44, and 46, each of which can extend distally from the base 40. The first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b can be configured as arms extending distally from the frame 48. Furthermore, the first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b can define the respective corners of the outer circumference of the implant body in a plane oriented along the transverse direction T and the lateral direction A, respectively.

[0047] As shown, the first and second upper body portions 34a and 34b can be L-shaped in a plane oriented along the transverse direction T and the transverse direction A. That is, each of the first and second upper body portions 34a and 34b can have a first region extending laterally to define the outer upper surface 35 and a second region extending downward toward the first and second lower body portions 36a and 36b. Similarly, the first and second lower body portions 36a and 36b can be L-shaped in a plane oriented along the transverse direction T and the transverse direction A. That is, each of the first and second lower body portions 36a and 36b can have a first region extending laterally to define the outer lower surface 37 and a second region extending upward toward the first and second upper body portions 36a and 36b.

[0048] Therefore, the upper mesh portion 38 can extend from the first region of the first upper body portion 34a to the first region of the second upper body portion 34b. The lower mesh portion can extend from the first region of the first lower body portion 36a to the first region of the second lower body portion 36b. The first side mesh portion 44 can extend from the second region of the first upper body portion 34a to the second region of the first lower body portion 36a. The second side mesh portion 46 can extend from the second region of the second upper body portion 36a to the second region of the second lower body portion 36b. It is recognized that any one or more of the mesh portions, up to all of them, can be interrupted by one or more additional upper body portions, lower body portions, or side body portions.

[0049] The second regions of the first upper body portion 34a and the first lower body portion 36a can define the first and second portions, respectively, of the first side wall 50 of the implant body 28. The second regions of the second upper body portion 34b and the second lower body portion 36b can define the first and second portions, respectively, of the second side wall 52 of the implant body 28. Thus, the first and second portions of the first and second side walls 50 and 52 are continuous with the first regions of the first and second upper body portions 34a and 34b and the first and second lower body portions 36a and 36b, respectively, along their respective planes oriented, for example, along the transverse direction T and the lateral direction A. In other examples, the first and second portions of the first and second side walls 50 and 52 can be spaced apart from the first and second upper body portions 34a and 34b, and the first and second lower body portions 36a and 36b, respectively, along their respective planes oriented along the transverse direction T and the lateral direction A.

[0050] The first and second upper body portions 34a and 34b and the first and second lower body portions 36a and 36b can extend distally from the base 40. When the intervertebral implant 20 is in the first insertion configuration, the first and second lower body portions 36a and 36b can extend parallel to each other. Furthermore, when the intervertebral implant 20 is in the first insertion configuration, the first and second lower body portions 36a and 36b can be spaced apart from each other by a first distance. Alternatively, when the intervertebral implant 20 is in the first insertion configuration, the first and second upper body portions 36a and 36b can be adjacent to each other. Similarly, the first upper body portion 34a and the first lower body portion 36a can extend parallel to each other. Furthermore, when the intervertebral implant 20 is in the first insertion configuration, the first upper body portion 34a and the first lower body portion 36a can be spaced apart from each other by, for example, a first distance. Alternatively, the first upper body portion 34a and the first lower body portion 36a can be adjacent to each other when the intervertebral implant 20 is in the first insertion configuration. Similarly, the second upper body portion 34b and the second lower body portion 36b can extend parallel to each other. Furthermore, the second upper body portion 34b and the second lower body portion 36b can be spaced apart from each other by, for example, a first distance when the intervertebral implant 20 is in the first insertion configuration. Alternatively, the second upper body portion 34b and the second lower body portion 36b can be adjacent to each other when the intervertebral implant 20 is in the first insertion configuration.

[0051] The distal end 30 of the implant body 28 can be tapered to facilitate insertion of the intervertebral implant 20 into the intervertebral space. That is, each of the first and second upper body portions 34a to 34b and each of the first and second lower body portions 36a to 36b can be tapered at the distal end 30 of the implant body 28 from at least one or more of the other of the first and second upper body portions 34a to 34b and the first and second lower body portions 36a and 36b toward all of them.

[0052] Referring here to Figures 3A to 3C, the implant body 28 is configured to support the actuator 29 within the working cavity 50 of the implant body 28. In particular, the actuator 29 can be placed within the working cavity 50 manufactured by an additive manufacturing process. Therefore, in one example, the actuator 29 does not need to be separately inserted into the working cavity 50. Furthermore, the actuator 29 can be sized so that it cannot be inserted into the working cavity. However, it should be recognized that this disclosure is not limited to additive manufacturing of the intervertebral implant 20 unless otherwise indicated.

[0053] The actuator 29 may include a shaft portion 53 and an expansion head 54 extending from the shaft portion 53 along the transverse direction T and the lateral direction A. For example, the expansion head 54 may extend both upward and downward from the shaft portion 53 along the transverse direction T, and may further extend from the shaft portion 53 in the opposite lateral direction A. The expansion head 54 defines first and second lateral expansion surfaces 55 and first and second transverse expansion surfaces 57. The expansion head 54 may extend from the distal end of the shaft portion 53. When an operating force is applied to the actuator 29 along the longitudinal direction L, the implant body 28 can guide the actuator 29 to translate along the longitudinal direction L within the operating cavity. For example, the implant body 28 may include one or more guide arms 33 oriented along the longitudinal direction L and received in a slot 31 of the actuator 29, thereby guiding the actuator 29 to translate along the longitudinal direction L. As will be described in more detail below, the expansion head 54 is configured to expand the implant body 28 along the first and second expansion directions. In one example, the expansion head 54 defines the lateral and transverse expansion surfaces 55 and 57, but it should be noted that any part of the actuator 29, such as the shaft portion 53 of the actuator 29, can alternatively define the lateral and transverse expansion surfaces 55 and 57.

[0054] The implant body 28 can define first and second inner surfaces 56 and 58 that are spaced apart from each other along the transverse direction A. The inner surfaces 56 and 58 can be inclined so as they extend along the transverse direction A as they extend along the longitudinal direction L. That is, each of the first and second inner surfaces 56 and 58 can include the first and second inclined inner surfaces 60 and 62, respectively, in the transverse extension region 59 of the implant body 62. Each of the first and second inclined surfaces 60 and 62 tapers inward toward the other of the first and second inner surfaces 56 and 58 as it extends distally. The first and second inclined surfaces 60 can be mirror images of each other with respect to an intermediate plane oriented along the longitudinal direction L and the transverse direction T. Thus, the first and second inclined surfaces 60 and 62 can define equally opposite slopes in one example. Furthermore, the first and second inclined surfaces 60 and 62 can be aligned with each other along the transverse direction A. Alternatively, the slopes of the first and second inclined sides 60 and 62 can be different from each other. The first inclined side 60 can be defined by both the first upper body portion 34a and the first lower body portion 36a. Similarly, the second inclined side 62 can be defined by both the second upper body portion 34b and the second lower body portion 36b.

[0055] The implant body 28 can define an inner upper surface 64 and an inner lower surface 66 that are spaced apart from each other along the transverse direction T. The inner upper surface 64 and the inner lower surface 66 can be inclined along the transverse direction T as they extend along the longitudinal direction L in the lateral expansion region 61 of the implant body 28. That is, the inner upper surface 64 defines an upper inclined surface 65, and the inner lower surface 66 defines a lower inclined surface 67. The inclined surfaces 65 and 67 each taper inward toward the other inner upper surface 64 and inner lower surface 66 as they extend distally. In one example, the upper inclined surface 65 and the lower inclined surface 67 can define equally opposite slopes. Alternatively, the slopes of the upper and lower inclined surfaces 65 and 67 can be different from each other.

[0056] One or both of the inclined surfaces 65 and 67 can be stepped. Thus, the inclined surfaces 65 and 67 can include inclined surface segments 68 and risers 70 positioned between adjacent inclined surface segments 68. The risers 70 can have a greater gradient than the gradient of the inclined surface segments 68. Furthermore, each of the risers 70 of the upper inclined surface 65 can have the same gradient, and each of the risers 70 of the lower inclined surface 67 can have the same gradient. The risers 70 of the upper inclined surface 65 and the lower inclined surface 67 can have the same gradient as each other. The risers 70 can have a length along the longitudinal direction L that is shorter than the length of the inclined surface segments 68 along the longitudinal direction L.

[0057] The inclined surfaces 65 and 67 can be mirror images of each other with respect to an intermediate plane oriented along the longitudinal direction L and the transverse direction T. Therefore, each of the inclined surface segments 68 of the upper inclined surface 65 can have the same gradient, and each of the inclined surface segments 68 of the lower inclined surface 67 can have the same gradient. Furthermore, the inclined surface segments 68 of the upper inclined surface 65 and the inclined surface segments 68 of the lower inclined surface 67 can have the same gradient. The inclined surfaces 65 and 67 can be aligned with each other along the transverse direction T, thereby aligning the inclined surface segments 68 of the inclined surfaces 65 and 67 with each other along the transverse direction T, and aligning the risers 70 of the inclined surfaces 65 and 67 with each other along the transverse direction T.

[0058] Continuing to refer to Figure 3C, the actuator 29 may define at least one actuator ratchet tooth 72, such as a plurality of actuator ratchet teeth 72. The actuator ratchet teeth 72 may be located on one side of the actuator 29 or on the opposite side of the actuator 29. In one example, the actuator 29 includes first and second rows of actuator ratchet teeth 72 oriented along the longitudinal direction. The first and second rows of actuator ratchet teeth 72 may be opposite each other along the transverse direction T. Alternatively, the first and second rows of actuator ratchet teeth 72 may be opposite each other along the transverse direction A. Alternatively, further, the actuator ratchet teeth 72 may have a length that extends around the actuator 29 by a distance sufficient to define the first and second portions on opposite sides of the actuator 29. The actuator ratchet teeth 72 may be located on the shaft portion 53 of the actuator 29, but can alternatively be located as desired.

[0059] The implant body 28 may further define at least one implant ratchet tooth 74 configured to interlock with at least one actuator ratchet tooth 72. The ratchet teeth 72 and 74 are configured to interlock to resist the movement of the actuator 29 in both the expansion direction, which repeats the implant body 28 from a first insertion configuration to a second expansion configuration, and the contraction direction, which repeats the implant body from the second expansion configuration to the first insertion configuration. In one example, the implant body 28 may include first and second rows of at least one implant ratchet tooth 74. The first and second rows of at least one implant ratchet tooth can be aligned with first and second rows of at least one actuator tooth 72. Thus, the first and second rows of at least one implant ratchet tooth can interlock with first and second rows of at least one actuator ratchet tooth 72.

[0060] Furthermore, at least one actuator ratchet tooth 72 and at least one implant ratchet tooth 74 can cam each other as the actuator 29 translates relative to the implant body 28 along the longitudinal direction L. For example, at least one or both of the at least one actuator ratchet tooth 72 and at least one implant ratchet tooth 74 can be displaced away from the other of the at least one actuator ratchet tooth 72 and at least one implant ratchet tooth 74.

[0061] In one example, the implant body 28 includes at least one flexible arm 76 that carries at least one implant ratchet tooth 74. The at least one implant ratchet tooth 74 can be a single ratchet tooth 74 as shown, or multiple ratchet teeth 74. For example, the implant body 28 includes first and second flexible arms 76, each carrying at least one implant ratchet tooth 74. Furthermore, at least one actuator tooth 72 is configured as multiple actuator teeth 72. When the actuator 29 is translated along the distal and proximal directions, the at least one implant ratchet tooth 74 performs a cam action on the actuator teeth 72 when the flexible arm 76 selectively deflects elastically away from the actuator teeth 72. When at least one implant ratchet tooth 74 is positioned between adjacent actuator teeth 72, the teeth 72 and 74 define mechanical interference with each other to prevent unintentional movement of the actuator 29. Mechanical interference can be overcome by applying an operating force to the actuator 29 along the longitudinal direction. The actuator 29 can be guided to translate within the implant body 28 so that the actuator ratchet teeth 72 align with the implant ratchet teeth 74 along the longitudinal direction L. That is, the implant body 28 can prevent the actuator 29 from rotating relative to the implant body by an amount that does not result in longitudinal alignment of the actuator teeth 72 with the implant ratchet teeth.

[0062] Each arm 76 carries a single implant ratchet tooth 74, and the actuator 29 carries multiple actuator ratchet teeth 72 in the illustrated example, but other configurations are conceivable. For example, each row of implant bodies 28 may alternatively include multiple implant ratchet teeth 74 configured to mesh with at least one actuator ratchet tooth 72. Furthermore, each row of actuators 29 may include a single actuator ratchet tooth 72 or multiple actuator ratchet teeth 72. In addition, the actuator ratchet teeth 72 may be positioned on deflectable actuator arms as needed.

[0063] In yet another example, referring to Figures 6A and 6B, the actuator 29 can be rotatable about its central longitudinal axis. Therefore, when the actuator is in a first rotational position, the actuator ratchet teeth 72 may not be aligned with the implant ratchet teeth 74 with respect to the longitudinal direction L. Thus, the actuator 29 can be freely translated along the longitudinal direction L on the implant body 28 without the actuator ratchet teeth 72 mechanically interfering with the implant ratchet teeth 74. Once the actuator 29 is translated to a desired longitudinal position, the actuator 29 can be rotated to a second rotational position, thereby positioning at least one implant ratchet tooth 74 between adjacent actuator ratchet teeth 72. In one example, the second rotational position may be offset by 90 degrees from the first rotational position. Alternatively or additionally, at least one actuator tooth 72 may be positioned between adjacent implant ratchet teeth 74. When the actuator 29 is in the second rotational position, the mechanical interference defined by the ratchet teeth 72 and 74 prevents the actuator 29 from moving relative to the implant body 28 along the longitudinal direction L.

[0064] The operation of the intervertebral implant 20 will now be explained with reference to Figures 4A to 5C. In particular, the actuator 29 is movable in the implant body 28 from the initial position shown in Figure 4A to the first expansion position shown in Figure 4B, and thereafter from the first expansion position to the second expansion position shown in Figures 5B to 5C. The movement of the actuator 29 from the initial position to the first expansion position causes the actuator 29 to expand the implant body 28 along the first expansion direction from the first configuration shown in Figure 4A to the first expansion shown in Figure 4B. The movement of the actuator 29 from the first expansion position to the second expansion position causes the actuator 29 to expand the implant body 28 along the second expansion direction perpendicular to the first expansion direction, as shown in Figures 5B to 5C. In one example, the actuator 29 is capable of translation distally from the initial position to the first expansion position, and further from the first expansion position to the second expansion position. For example, actuator 29 can be translated distally without rotating. Alternatively, in an alternative example, actuator 29 can be configured as a screw that rotates when it is translated distally.

[0065] Referring here to Figures 4A and 4B, in particular, when the actuator 29 is in its initial position, the implant body 28 is in a first or initial configuration. When the implant body 28 is in a first or initial configuration, it defines a first width along the lateral direction A and a first height along the transverse direction T. Furthermore, when the actuator 29 is in its initial position, the expansion head 54 can be spaced proximal to the inclined sides 60 and 62. Alternatively, the expansion head 54 can be aligned with the inclined sides 60 and 62 along the lateral direction A. Thus, when the actuator 29 is in its initial position, the actuator has not yet expanded the implant body along the first expansion direction which can be defined by the lateral direction A.

[0066] When the actuator 29 is translated distally from a first or initial position to a first expanded position in the lateral expansion region 59, the lateral expansion surface 55 rides along the first and second inclined sides 60 and 62, thereby expanding the implant body 28 along lateral direction A from its initial configuration to a lateral expansion configuration that defines the first expansion. The implant body 28 defines a first lateral distance between the proximal ends of the inclined sides 60 and 62 along lateral direction A, and a second lateral distance between the distal ends of the inclined sides, which is smaller than the first lateral distance. Therefore, when the lateral expansion surface 55 rides along the first and second inclined sides 60 and 62, the lateral expansion surface 55 expands the implant body 28 along the first expansion direction to a second width along lateral direction A that is greater than the first width. The first and second widths can be measured from the outer surface of the first side wall 50 to the outer surface of the second side wall 52.

[0067] In particular, each of the upper body 34 and the lower body 36 can expand along the lateral direction A. For example, the actuator 29 can move at least one or both of the first upper body portion 34a and the second upper body portion 34b (see Figure 2A) away from the other of the first upper body portion 34a and the second upper body portion 34b along the lateral direction A. Furthermore, the actuator 29 can move at least one or both of the first lower body portion 36a and the second lower body portion 36b (see Figure 2B) away from the other of the first lower body portion 36a and the second lower body portion 36b along the lateral direction A. Furthermore, the actuator 29 can move either or both of the first side wall 50 and the second side wall 52 away from the other of the first side wall 50 and the second side wall 52. The upper and lower mesh portions 38 and 42 can expand along the lateral direction A as the implant body 28 expands along the lateral direction A.

[0068] In one example, the first and second inner surfaces 56 and 58 are inclined, but it should be noted that, alternatively or additionally, the lateral expansion surface 55 can be inclined. That is, the lateral expansion surface may taper toward each other along the lateral direction A as it extends distally. Therefore, as the actuator 29 moves distally, the lateral expansion surface 55 can expand the implant body 28 along the lateral direction A.

[0069] As described above, the first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b can each extend distally from the base 40. Therefore, as the implant body 28 expands along the first expansion direction, the first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b can bend laterally outward relative to the base 40. Thus, the width of the implant body 28 along the lateral direction A at the proximal ends of the first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b can be smaller than the width of the implant body 28 along the lateral direction A at the distal ends of the first and second upper body portions 34a-34b and the first and second lower body portions 36a-36b.

[0070] Referring here to Figures 5A to 5C, when the implant body 28 is expanded along the first expansion direction, the actuator is further translated distally from the first expansion position to the second expansion position, thereby expanding the implant to a second or expanded configuration. The second expansion position can be any position that expands the implant body 28 along the second expansion direction after expansion along the lateral direction A is completed. As described herein, the second expansion direction moves at least one or both of the upper body 34 and the lower body 36 away from the other upper body 34 and the lower body 36.

[0071] When the actuator 29 is in the first expansion position, the implant body 28 has a first height along the transverse direction T. The implant body 28 also has a first height when the actuator 29 is in the initial position and the implant body 28 is in the first or initial configuration. Furthermore, when the actuator 29 is in the first expansion position, the expansion head 54 can be spaced apart from the upper inclined surface 65 and the lower inclined surface 67 along the proximal direction. Alternatively, the expansion head 54 can be aligned with the upper and lower inclined surfaces 65 and 67 along the transverse direction T. When the actuator 29 is in the first expansion position, the actuator 29 has not yet expanded the implant body 28 along a second expansion direction that can be defined by the transverse direction T.

[0072] As the actuator 29 translates distally from the first expansion position toward the second expansion position, the transverse expansion surface 57 rides along the upper inclined surface 65 and the lower inclined surface 67, thereby expanding the implant body 28 along the transverse direction T. The implant body 28 defines a first distance between the proximal ends of the upper and lower inclined surfaces 65 and 67 along the transverse direction T, and a second transverse distance between the distal ends of the upper and lower inclined surfaces 65 and 67, which is smaller than the first transverse distance. Therefore, as the transverse expansion surface 57 rides along the upper and lower inclined surfaces 65 and 67, the transverse expansion surface 57 expands the implant body 28 to a second height along the transverse direction T that is greater than a first height along the transverse direction A. In particular, the actuator 29 separates at least one or both of the upper body 34 and the lower body 36 (see Figure 2A) from the other along the transverse direction T. The first and second lateral mesh portions 44 and 46 can expand along the transverse direction as the implant body 28 expands along the transverse direction T. The mesh portions 38, 42, 44, and 46 can be constructed according to any preferred embodiment as needed. In one example, the mesh portions may include a plurality of interconnected links that are movable relative to each other, allowing the mesh portions to expand along their respective directions.

[0073] As shown in Figure 5C, when the implant 20 is fully expanded along the second expansion direction, the upper inclined surface 65 and the lower inclined surface 67 can transition from the above inclination to a second orientation with a smaller angle with respect to the longitudinal direction L. For example, at least one or more of the upper and lower inclined surfaces 65 and 67 can be oriented substantially along the longitudinal direction L, such as within ±5 degrees of the longitudinal direction L.

[0074] As described above, the upper and lower bodies 34 and 36 can each extend distally from the base 40. Therefore, as the implant body 28 expands along the second expansion direction, the upper and lower bodies 34 and 36 can bend outward relative to the base 40 along the transverse direction T. Thus, the height of the implant body 28 along the transverse direction T at the proximal ends of the upper body 34 and lower body 36 can be less than the height of the implant body 28 along the transverse direction T at the distal ends of the upper body 34 and lower body 36. As a result, expansion of the implant body 28 along the second expansion direction can change, for example, increase, the lordosis angle defined by the outer upper surface 35 and outer lower surface 37. Further expansion of the implant body 28 along the second expansion direction can further change the lordosis angle.

[0075] As described above, the inclined surfaces 65 and 67 may include inclined surface segments 68 and risers 70 positioned between adjacent inclined surface segments 68. Thus, as the actuator 29 is translated distally, the transversely extended surface 57 alternately rests along the inclined surface segments 68 and risers 70. The implant body 28 can achieve a fully extended height when the actuator 29 has been translated to a position where the actuator 29 can no longer be translated distally. Furthermore, as described above, the implant body 28 and the actuator 29 include respective ratchet teeth 72 and 74 configured to engage with each other to lock the implant body 28 into a second or extended position. When the ratchet teeth 72 and 74 are engaged with each other, the actuator 29 can be prevented from translating proximal to the implant body 28. In particular, at least one of the proximal surface of the implant ratchet tooth 74 and the distal surface of the actuator ratchet tooth 72 can be oriented to prevent the ratchet teeth 72 and 74 from camming each other proximal to each other. Therefore, the actuator 29 can be prevented from translating proximal to the implant body 28.

[0076] As a result, the actuator 29 can be translated distally to a position where the transversely expanded surface 57 engages with the respective inclined surfaces 65 and 67. The engagement with the ratchet teeth 72 and 74 prevents the actuator 29 from translating proximal, which causes the implant to collapse along the transverse direction T. Thus, the implant can be expanded to a position with a height along the transverse direction T that is smaller than the fully expanded height. Furthermore, the ratchet teeth 72 and 74 can be engaged when the actuator 29 is in the first expanded position. Thus, the implant 28 can be locked in a laterally expanded configuration to prevent contraction of the implant 28 along the transverse direction A without expanding along the transverse direction T. Furthermore, the implant 28 can be locked in a laterally expanded configuration and in a transversely expanded configuration having an expanded height smaller than the fully expanded height. Thus, the expansion of the implant 20 along the transverse direction T can be controlled after the implant 20 has been fully expanded along the transverse direction A.

[0077] The first and second inner surfaces 56 and 58 in the transverse expansion region 61 can be oriented along the respective planes defined by the transverse direction T and the longitudinal direction L when the implant 20 achieves a first expansion. Therefore, the lateral expansion surface 55 rides along the first and second inner surfaces 56 and 58 as the actuator is translated by distal translation of the actuator 29 in the transverse expansion region 61, so the lateral expansion surface 55 does not expand the implant body 28 along the lateral direction A. Thus, distal translation of the actuator head 54 in the transverse expansion region 61 causes the implant to expand along the transverse direction T without expanding along the lateral direction A. Alternatively, the first and second inner surfaces 56 and 68 can be sloped inward toward each other along the lateral direction A as they extend distally. Thus, distal translation of the actuator 29 in the transverse expansion region 61 allows the lateral expansion surface 55 of the actuator 29 to further expand the implant body 28 along the lateral direction A. In one example, the gradients of the first and second inner surfaces 56 and 68 can be smaller than the gradients of the inclined inner surfaces 60 and 62.

[0078] In one example, the upper surface 64 and the lower surface 66 are respectively It should be recognized that, although inclined, the transverse expansion surface 57 can be inclined alternatively or additionally. That is, the transverse expansion surface 57 can taper toward each other along the transverse direction T as it extends distally. Therefore, as the actuator 29 moves distally, the transverse expansion surface 57 can expand the implant body 28 along the transverse direction T.

[0079] As described above, at least a portion to up to the entirety of the transverse expansion region 61 can be positioned distal to the lateral expansion region 59. Therefore, at least a portion to up to the entirety of each of the upper and lower inclined surfaces 65 and 67 can be positioned distal to the inclined sides 60 and 62. Thus, in one example, the movement of the actuator 29 from the initial position to the first expansion position does not expand the implant body 28 along the second expansion direction. Alternatively, a portion of the vertical expansion region 61 can partially overlap with the lateral expansion region 59. Thus, the implant body 28 can expand further along the lateral direction A as it expands along the transverse direction T. In both examples, at least a portion of the vertical expansion region 61 extends distal to the lateral expansion region 59, and the implant is expandable along the transverse direction T without expanding along the lateral direction A.

[0080] As described above, the first expansion direction can be along the lateral direction A, and the second expansion direction can be along the transverse direction T. Alternatively, the first expansion direction can be along the transverse direction T, and the second expansion direction can be along the lateral direction A. In this regard, at least a portion of the lateral expansion region 59 can be located distal to the transverse expansion region 61.

[0081] It should be understood that the examples and discussions of embodiments shown in the figures are for illustrative purposes only and should not be construed as limiting the disclosure. Those skilled in the art will understand that this disclosure is intended to encompass a variety of embodiments. In addition, it should be understood that the concepts described above, along with the embodiments described above, may be used alone or in combination with any of the other embodiments described above. Unless otherwise specified, it should be further understood that the various alternative embodiments described above with respect to one of the exemplary embodiments may be applied to all embodiments described herein.

[0082] [Implementation Method] (1) Intervertebral implants, An implant body defining an upper body configured to face the upper vertebra and a lower body configured to face the lower vertebra, The device comprises an actuator supported by the implant body, wherein the actuator is movable within the implant body from an initial position to a first expanded position, and subsequently from the first expanded position to a second expanded position. An intervertebral implant, wherein the actuator expands the implant body along a first expansion direction by moving the actuator from the initial position to the first expansion position, and the actuator expands the implant body along a second expansion direction perpendicular to the first expansion direction by moving the actuator from the first expansion position to the second expansion position. (2) The intervertebral implant according to Embodiment 1, wherein the actuator is capable of translation from the initial position to the first expanded position, and further from the first expanded position to the second expanded position. (3) The intervertebral implant according to Embodiment 2, wherein the actuator is capable of translation distally from the initial position to the first expansion position, and further distally from the first expansion position to the second expansion position. (4) The intervertebral implant according to Embodiment 1, wherein the first expansion direction is perpendicular to the distal direction, and the second expansion direction is perpendicular to the distal direction and the first direction. (5) The intervertebral implant according to Embodiment 1, wherein the actuator defines a head that expands the implant body along the first expansion direction and the second expansion direction.

[0083] (6) The intervertebral implant according to Embodiment 1, wherein the movement of the actuator from the initial position to the first expansion position does not expand the implant body along the second expansion direction. (7) The intervertebral implant according to Embodiment 6, wherein the movement of the actuator from the first expansion position to the second expansion position does not expand the implant body along the first expansion direction. (8) The intervertebral implant according to Embodiment 1, wherein the movement of the actuator from the first expansion position to the second expansion position does not expand the implant body along the first expansion direction. (9) The intervertebral implant according to Embodiment 1, wherein the first expansion direction expands each of the upper body and the lower body, and the second expansion direction moves at least one of the upper body and the lower body away from the other of the upper body and the lower body. (10) The intervertebral implant according to Embodiment 1, wherein 1) the implant body defines opposing inclined inner surface and inclined upper and lower surfaces, and at least each portion of the inclined inner upper and lower surfaces is spaced distally from the inclined inner surface, 2) the actuator rides along the inclined inner surface to expand the implant body in the first expansion direction, and 3) the actuator rides along the inclined inner upper and lower surfaces to expand the implant body in the second expansion direction.

[0084] (11) The intervertebral implant according to embodiment 10, wherein the inclined medial upper and lower surfaces are stepped. (12) The intervertebral implant according to Embodiment 10, wherein the actuator comprises a shaft portion and an expanding head extending from the shaft portion in both the first and second expansion directions, and the expanding head expands the implant body in both the first and second expansion directions. (13) The intervertebral implant according to Embodiment 1, wherein the expansion of the implant body along the second expansion direction changes the lordosis angle defined by the outer upper surface of the upper body and the outer lower surface of the lower body. (14) The intervertebral implant according to embodiment 13, wherein the expansion of the implant body along the second expansion direction increases the lordosis angle. (15) The intervertebral implant according to Embodiment 1, wherein the implant body comprises a base and a frame including an upper body and a lower body, each extending distally from the base.

[0085] (16) The intervertebral implant according to embodiment 15, wherein the upper body and the lower body bend around the base when the implant body expands along the second expansion direction. (17) The intervertebral implant according to Embodiment 1, wherein the upper body comprises a first upper body portion, a second upper body portion, and an upper expandable mesh connecting the first upper body portion to the second upper body portion, and the lower body portion comprises a first lower body portion, a second lower body portion, and a lower expandable mesh connecting the first lower body portion to the second lower body portion. (18) The intervertebral implant according to Embodiment 17, wherein the expansion of the implant body along the first expansion direction causes 1) at least one of the first upper body portion and the second upper body portion to move away from the other of the first upper body portion and the second upper body portion, and 2) at least one of the first lower body portion and the second lower body portion to move away from the other of the first lower body portion and the second lower body portion. (19) The intervertebral implant according to embodiment 18, wherein the upper mesh expands when at least one of the first upper body portion and the second upper body portion moves away from the other of the first upper body portion and the second upper body portion, and the lower mesh expands when at least one of the first lower body portion and the second lower body portion moves away from the other of the first lower body portion and the second lower body portion. (20) Further comprising an expandable first side mesh connecting the first upper body portion to the first lower body portion, and an expandable second side mesh connecting the second upper body portion to the second lower body portion, The intervertebral implant according to embodiment 19, wherein the first lateral mesh and the second lateral mesh expand as the implant body expands along the second direction.

Claims

1. 1. An intervertebral implant comprising: an implant body defining an upper body configured to face the superior vertebra and a lower body configured to face the inferior vertebra; an actuator supported by the implant body, the actuator being movable within the implant body from an initial position to a first expanded position and subsequently from the first expanded position to a second expanded position; An intervertebral implant, wherein movement of the actuator from the initial position to the first expanded position causes the actuator to expand the implant body along a first expansion direction, and movement of the actuator from the first expanded position to the second expanded position causes the actuator to expand the implant body along a second expansion direction perpendicular to the first expansion direction.

2. The intervertebral implant of claim 1 , wherein the actuator is translatable from the initial position to the first expanded position and from the first expanded position to the second expanded position.

3. The intervertebral implant of claim 2 , wherein the actuator is translatable distally from the initial position to the first expanded position and further translatable distally from the first expanded position to the second expanded position.

4. The intervertebral implant of claim 1 , wherein the first direction of expansion is perpendicular to the distal direction and the second direction of expansion is perpendicular to the distal direction and the first direction.

5. The intervertebral implant of claim 1 , wherein the actuator defines a head that causes the implant body to expand along the first direction of expansion and the second direction of expansion.

6. The intervertebral implant of claim 1 , wherein movement of the actuator from the initial position to the first expanded position does not cause the implant body to expand along the second expansion direction.

7. 7. The intervertebral implant of claim 6, wherein movement of the actuator from the first expanded position to the second expanded position does not cause the implant body to expand along the first expansion direction.

8. 10. The intervertebral implant of claim 1, wherein movement of the actuator from the first expanded position to the second expanded position does not cause the implant body to expand along the first expansion direction.

9. 2. The intervertebral implant of claim 1, wherein the first direction of expansion expands each of the upper body and the lower body, and the second direction of expansion moves at least one of the upper body and the lower body away from the other of the upper body and the lower body.

10. 2) the actuator rides along the inclined inner sides to expand the implant body along the first expansion direction; and 3) the actuator rides along the inclined inner upper and lower sides to expand the implant body along the second expansion direction.

11. The intervertebral implant of claim 10 , wherein the sloping inner upper and lower surfaces are stepped.

12. 11. The intervertebral implant of claim 10, wherein the actuator comprises a shaft portion and an expansion head extending from the shaft portion along both the first expansion direction and the second expansion direction, the expansion head causing the implant body to expand along the first expansion direction and the second expansion direction.

13. 10. The intervertebral implant of claim 1, wherein expansion of the implant body along the second expansion direction changes a lordotic angle defined by the outer superior surface of the upper body and the outer inferior surface of the lower body.

14. 14. The intervertebral implant of claim 13, wherein expansion of the implant body along the second expansion direction increases the lordosis angle.

15. The intervertebral implant of claim 1 , wherein the implant body comprises a frame including a base and each of the upper and lower bodies extending distally from the base.

Images