Patent Description:
The embodiments are generally directed to implants for supporting bone growth in a patient.

A variety of different implants are used in the body. Implants used to stabilize an area and promote bone ingrowth provide both stability (i.e. minimal deformation under pressure over time) and space for bone ingrowth.

Spinal fusion, also known as spondylodesis or spondylosyndesis, is a surgical treatment method used for the treatment of various morbidities, such as: degenerative disc disease, spondylolisthesis (slippage of a vertebra), spinal stenosis, scoliosis, fracture, infection, or tumor. The aim of the spinal fusion procedure is to reduce instability, and thus, pain. It should be mentioned at this point that surgical treatment methods are not part of the invention, but represent background art that may be useful for understanding the invention.

In preparation for the spinal fusion, most of the intervertebral disc is removed. An implant, such as a spinal fusion cage, may be placed between the vertebrae to maintain spine alignment and disc height. The fusion (i.e., bone bridge) occurs between the endplates of the vertebrae. Further reference regarding prior art is made to <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and <CIT>.

According to the invention, the present disclosure is directed to an implant that includes a housing having a peripheral frame including an inner edge defining central opening in a central portion of the implant. The implant includes also include a blade located within the central opening, the blade having a retracted position in the housing and an extended position where the blade extends outwardly from the housing. In addition, the implant includes a blade actuating component comprising a driven shaft portion and a blade engaging portion. The blade actuating component is configured to be translated to move the blade between the retracted position and the extended position. Also, the inner edge of the peripheral frame may include a posterior edge configured to support the blade in two locations.

In another aspect, the present disclosure is directed to an implant including a housing having a peripheral frame including an inner edge defining central opening in a central portion of the implant. The implant may also include a blade located within the central opening and having a retracted position in the housing and an extended position where the blade extends outwardly from the housing. In addition, the implant may include a blade actuating component comprising a driven shaft portion and a blade engaging portion. The blade actuating component may be configured to be translated to move the blade between the retracted position and the extended position. The housing may be formed, at least in part, from polyether ether ketone (PEEK) or (PEKK). Further, at least one radiopaque marker may be embedded in a portion of the housing.

In another aspect, the present disclosure is directed to an implant including a housing having a peripheral frame including an inner edge defining central opening in a central portion of the implant. The implant may also include a blade located within the central opening, the blade having a retracted position in the housing and an extended position where the blade extends outwardly from the housing. In addition, the implant may include a blade actuating component comprising a driven shaft portion and a blade engaging portion. The blade actuating component may be configured to be translated to move the blade between the retracted position and the extended position. The housing may be formed at least in part from polyether ether ketone (PEEK). In addition, the implant may include at least one engagement portion extending from an outer surface of the peripheral frame, the engagement portion including a recess configured to receive a gripping element of an insertion tool configured to hold the implant during an implantation procedure.

In another aspect, the present disclosure is directed to an implant a housing having a peripheral frame including an inner edge defining a central opening in a central portion of the implant. The implant includes a first blade located within the central opening and having a retracted position in the housing and an extended position where the blade extends outwardly from the housing in a superior direction. In addition, the implant includes a second blade located within the central opening and having a retracted position in the housing and an extended position where the blade extends outwardly from the housing in an inferior direction. Further, the implant includes a blade actuating component comprising a driven shaft portion and a blade engaging portion, wherein the blade actuating component is configured to be translated to move the first blade and the second blade between the retracted position and the extended position. The first blade includes a first protruding portion, and the blade actuating component includes a first channel configured to receive the first protruding portion of the first blade. The first protruding portion of the first blade and the first channel in the blade actuating component are arranged at a non-zero angle with respect to a vertical axis such that translation of the blade actuating component moves the first blade from the retracted position to the extended position. In addition, the second blade includes a second protruding portion and the blade actuating component includes a second channel configured to receive the second protruding portion of the second blade. The second protruding portion of the second blade and the second channel in the blade actuating component are arranged at a non-zero angle with respect to a vertical axis such that translation of the blade actuating component moves the second blade from the retracted position to the extended position.

Other systems, methods (not claimed), features and advantages of the embodiments will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods (not claimed), features and advantages be included within this description and this summary, be within the scope of the embodiments, and be protected by the following claims. The present invention relates to an implant device as claimed hereafter. Preferred embodiments of the invention are set forth in the dependent claims.

The components in the figures are not necessarily to scale, with emphasis instead being placed upon illustrating the principles of the embodiments.

The embodiments described herein are directed to an implant for use in a spine. The embodiments include implants with a body and one or more blades. In addition to the various provisions discussed below, any embodiments may make use of any of the body/support structures, blades, actuating components or other structures disclosed in<CIT>, and titled "Interbody Fusion Device and System for Implantation," <CIT>, currently <CIT> and titled "Implant With Deployable Blades," and<CIT>, and titled "Insertion Tool For Implant And Methods of Use.

<FIG> is a schematic view of an embodiment of an implant <NUM>. For purposes of context, implant <NUM> is shown adjacent to a depiction of a spinal column <NUM> in a human body <NUM>. In <FIG>, an embodiment of implant <NUM> is shown as it is being inserted into human body <NUM> with the use of an insertion tool <NUM>. It should be understood that the relative size of implant <NUM> and insertion tool <NUM> as depicted with human body <NUM> have been adjusted for purposes of illustration. For purposes of this disclosure, implant <NUM> may also be referred to as a cage or fusion device. In some embodiments, implant <NUM> is configured to be implanted within a portion of the human body. In some embodiments, implant <NUM> may be configured for implantation into the spine. In some embodiments, implant <NUM> may be a spinal fusion implant, or spinal fusion device, which is inserted between adjacent vertebrae to provide support and/or facilitate fusion between the vertebrae. For example, referring to <FIG>, a section of spinal column <NUM> is illustrated, where implant <NUM> has been positioned between a first vertebra <NUM> and a second vertebra <NUM>. Moreover, implant <NUM> is seen to include two blades (a first blade <NUM> and a second blade <NUM>), which extend from the superior and inferior surfaces of implant <NUM>. Each of the blades has been driven into an adjacent vertebra (i.e., first vertebra <NUM> or second vertebra <NUM>) so as to help anchor implant <NUM>.

In some embodiments, implant <NUM> may be inserted using an anterior lumbar interbody fusion (ALIF) surgical procedure, where the disc space is fused by approaching the spine through the abdomen. In the ALIF approach, a three-inch to five-inch (that is ca. <NUM>,<NUM> to <NUM>) incision is typically made near the abdomen and the abdominal muscles are retracted to the side. In some cases, implant <NUM> can be inserted through a small incision in the front or anterior side of the body. In some cases, an anterior approach may afford improved exposure to the disc space to a surgeon. The anterior approach can allow a larger device to be used for the fusion, increasing the surface area for a fusion to occur and allowing for more postoperative stability. An anterior approach often makes it possible to reduce some of the deformity caused by various conditions, such as isthmic spondylolisthesis. Insertion and placement of the fusion device along the front of a human body can also re-establish the patient's normal sagittal alignment in some cases, giving individuals a more normal, inward curve to their lower back.

For purposes of clarity, reference is made to various directional adjectives throughout the detailed description and in the claims. As used herein, the term "anterior" refers to a side or portion of an implant that is intended to be oriented towards the front of the human body when the implant has been placed in the body. Likewise, the term "posterior" refers to a side or portion of an implant that is intended to be oriented towards the back of the human body following implantation. In addition, the term "superior" refers to a side or portion of an implant that is intended to be oriented towards a top (e.g., the head) of the body while "inferior" refers to a side or portion of an implant that is intended to be oriented towards a bottom of the body. Reference is also made herein to "lateral" sides or portions of an implant, which are sides or portions facing along a lateral direction of the body.

<FIG> is a schematic isometric view of an embodiment of implant <NUM>, according to an embodiment. As seen in <FIG>, implant <NUM> is understood to be configured with an anterior side <NUM> and a posterior side <NUM>. Implant <NUM> may also include a first lateral side <NUM> and a second lateral side <NUM>. Furthermore, implant <NUM> may also include a superior side <NUM> and an inferior side <NUM>.

Reference is also made to directions or axes that are relative to the implant itself, rather than to its intended orientation with regard to the body. For example, the term "distal" refers to a part that is located further from a center of an implant, while the term "proximal" refers to a part that is located closer to the center of the implant. As used herein, the "center of the implant" could be the center of mass and/or a central plane and/or another centrally located reference surface.

An implant may also be associated with various axes. Referring to <FIG>, implant <NUM> may be associated with a longitudinal axis <NUM> that extends along the longest dimension of implant <NUM> between first lateral side <NUM> and second lateral side <NUM>. Additionally, implant <NUM> may be associated with a posterior-anterior axis <NUM> (also referred to as a "widthwise axis") that extends along the widthwise dimension of implant <NUM>, between posterior side <NUM> and anterior side <NUM>. Moreover, implant <NUM> may be associated with a vertical axis <NUM> that extends along the thickness dimension of implant <NUM>, and which is generally perpendicular to both longitudinal axis <NUM> and posterior-anterior axis <NUM>.

An implant may also be associated with various reference planes or surfaces. As used herein, the term "median plane" refers to a vertical plane which passes from the anterior side to the posterior side of the implant, dividing the implant into right and left halves, or lateral halves. As used herein, the term "transverse plane" refers to a horizontal plane located in the center of the implant that divides the implant into superior and inferior halves. As used herein, the term "coronal plane" refers to a vertical plane located in the center of the implant that divides the implant into anterior and posterior halves. In some embodiments, the implant is symmetric or substantially symmetric about two planes, such as the median and the transverse plane.

<FIG> is a schematic isometric exploded view of implant <NUM> according to an embodiment. Referring to <FIG>, implant <NUM> is comprised of a body <NUM> and a cover <NUM>, which together may be referred to as a housing <NUM> of implant <NUM>. In some embodiments, a body and cover may be integrally formed. In other embodiments, a body and cover may be separate pieces that are joined by one or more fasteners. In the embodiment of <FIG>, body <NUM> and cover <NUM> are separate pieces that are fastened together using additional components of implant <NUM>.

Embodiments of an implant may include provisions for anchoring the implant into adjacent vertebral bodies. In some embodiments, an implant may include one or more anchoring members. In the embodiment of <FIG>, implant <NUM> includes a set of blades <NUM> that facilitate anchoring implant <NUM> to adjacent vertebral bodies following insertion of implant <NUM> between the vertebral bodies. Set of blades <NUM> may be further comprised of first blade <NUM> and second blade <NUM>. Although the exemplary embodiments described herein include two blades, other embodiments of an implant could include any other number of blades. For example, in another embodiment, three blades could be used. In another embodiment, four blades could be used, with two blades extending from the inferior surface and two blades extending from the superior surface of the implant. Still other embodiments could include five or more blades. In yet another embodiment, a single blade could be used.

An implant with blades can include provisions for moving the blades with respect to a housing of the implant. In some embodiments, an implant includes a blade actuating component that engages with one or more blades to extend and/or retract the blades from the surfaces of the implant. In the embodiment shown in <FIG>, implant <NUM> includes a blade actuating component <NUM>. In some embodiments, blade actuating component <NUM> is coupled to first blade <NUM> and second blade <NUM>. Moreover, by adjusting the position of blade actuating component <NUM> within housing <NUM>, first blade <NUM> and second blade <NUM> can be retracted into, or extended from, surfaces of implant <NUM>.

An implant can include provisions for locking the position of one or more elements of the implant. In embodiments where the position of a blade actuating component can be changed, an implant can include provisions for locking the actuating component in a given position, thereby also locking one or more blades in a given position, such as through the use of a threaded fastener or other type of securing mechanism. In the embodiment shown in <FIG>, implant <NUM> includes locking screw <NUM>. In some embodiments, locking screw <NUM> can be used to lock blade actuating component <NUM> in place within implant <NUM>, which ensures first blade <NUM> and second blade <NUM> remain in an extended or deployed position, as will be shown further below.

Embodiments can also include one or more fasteners that help attach a body to a cover. In some embodiments, pins, screws, nails, bolts, clips, or any other kinds of fasteners could be used. In the embodiment shown in <FIG>, implant <NUM> includes a set of pins <NUM> that help fasten cover <NUM> to body <NUM>. In the exemplary embodiments, two pins are used, including first pin <NUM> and second pin <NUM>. In other embodiments, however, any other number of pins could be used. In another embodiment, a single pin could be used. In still other embodiments, three or more pins could be used.

Referring now to <FIG>, four views are presented of an embodiment of body <NUM>. <FIG> is a schematic isometric superior side or top-down isometric view of body <NUM>. <FIG> depicts a schematic isometric inferior side or bottom-up isometric view of body <NUM>. <FIG> is a schematic posterior or rear side view of body <NUM>. <FIG> is a schematic anterior or front side view of body <NUM>. In different embodiments, body <NUM> may provide the posterior and anterior sides of housing <NUM>, as well as at least one lateral side of housing <NUM>.

In some embodiments, the lateral sides of a body may both have a lattice-like geometry. Various openings or apertures, as will be discussed below, can help reduce the overall weight of the implant, and/or decrease manufacturing costs associated with material usage. Furthermore, in some cases, openings can increase the surface area available throughout body <NUM>, and facilitate the application of bone growth promoting materials to the implant, and/or facilitate the coupling of the implant with the insertion tool, as will be discussed further below. In some other embodiments, the lateral sides could be configured as solid walls with one or more openings. Furthermore, by providing openings in the housing of the implant, there can be improved visual clarity regarding the degree or extent of blade deployment.

In the exemplary embodiment shown in <FIG>, body <NUM> has a generally oval cross-sectional shape in a horizontal plane. Furthermore, each of superior side <NUM> and inferior side <NUM> include at least one through-hole opening. For example, in <FIG> and <FIG>, it can be seen that implant <NUM> includes a first opening <NUM> and a second opening <NUM>. Each of first opening <NUM> and second opening <NUM> extend continuously through the thickness of implant <NUM> from superior side <NUM> to inferior side <NUM> in a direction substantially aligned with vertical axis <NUM>. While the openings can vary in size, shape, and dimension in different embodiments, in one embodiment, both first opening <NUM> and second opening <NUM> each have a generally half-circle, or semi-circle, cross-sectional shape along the horizontal plane.

In addition, as shown in <FIG>, posterior side <NUM> and anterior side <NUM> of body <NUM> have a generally oblong rectangular shape. Furthermore, in <FIG>, <FIG> and <FIG>, it can be seen that a sidewall <NUM> extends around the majority of perimeter of body <NUM>, extending between superior side <NUM> to inferior side <NUM> in a direction substantially aligned with vertical axis <NUM>, forming a periphery that surrounds or defines a majority of the outer surface of the implant. In some embodiments, first lateral side <NUM> and second lateral side <NUM> are substantially similar (i.e., can include substantially similar structural features), though in other embodiments, each side can include variations. There may be additional openings formed in implant <NUM> in some embodiments. In different embodiments, sidewall <NUM> can include a plurality of side openings or apertures, though in other embodiments, sidewall <NUM> can be substantially continuous or solid.

Referring back to <FIG>, it can be seen that first lateral side <NUM> includes a first aperture <NUM>, a second aperture <NUM>, a third aperture <NUM>, a fourth aperture <NUM>, a fifth aperture <NUM>, and a sixth aperture <NUM>. Each aperture can differ in shape in some embodiments. For example, first aperture <NUM> has a substantially oblong rectangular shape, second aperture <NUM> has a five-sided or substantially pentagonal shape, third aperture <NUM> and fifth aperture <NUM> each have a four-sided or substantially trapezoidal shape, fourth aperture <NUM> has a substantially round shape, and sixth aperture <NUM> has a six-sided or substantially hexagonal shape. In other embodiments, second lateral side <NUM> can include a fewer or greater number of apertures. It should be understood that second lateral side <NUM> can also include a plurality of apertures disposed in a similar arrangement as first lateral side <NUM> in some embodiments. The shapes of the various openings are configured to permit the implant body to be manufactured in the Direct Metal Laser Sintering (DMLS) process, as well as to provide support to the inferior and superior load bearing surfaces.

As shown in <FIG>, in one embodiment, anterior side <NUM> of body <NUM> includes guide opening <NUM>. Guide opening <NUM> extends through the thickness of sidewall <NUM> in a direction substantially aligned with posterior-anterior axis <NUM>. Guide opening <NUM> includes a chamber portion ("chamber") <NUM> and a hollow grooved portion (the hollow grooved portion will be discussed further below with respect to <FIG> and <FIG>). Chamber <NUM> can be understood to be connected with the grooved portion such that some components can pass from chamber <NUM> into the grooved portion (or vice versa).

In some embodiments, as will be discussed further below and shown generally in <FIG>, a portion of blade actuating component <NUM> can be configured to extend through or be received by the chamber portion. In other words, in some embodiments, the chamber portion can be sized and dimensioned to fit or extend closely around a portion of blade actuating component <NUM>. In <FIG>, it can be seen that chamber <NUM> comprises a generally oblong four-sided opening. In one embodiment, chamber <NUM> has a substantially oblong square or rectangular cross-sectional shape in a vertical plane. In <FIG>, chamber <NUM> extends between an outwardly-facing or distally oriented surface <NUM> of sidewall <NUM> and an inwardly-facing or proximally oriented surface <NUM> of sidewall <NUM>. As chamber <NUM> approaches proximally oriented surface <NUM>, there may be additional recessed regions or diagonal slots <NUM> which expand the size of guide opening <NUM>, and can be configured to snugly receive or fit various portions of blade actuating component <NUM>, as will be discussed further below. Furthermore, it can be understood that the cross-sectional shape of the chamber portion is configured to prevent rotation of the driven shaft portion when the drive shaft portion is inserted into the chamber portion.

Body <NUM> can also include additional reinforcement structures. For example, as shown in <FIG> and <FIG>, body <NUM> includes a first inner sidewall <NUM> extending in a direction substantially aligned with posterior-anterior axis <NUM>, and a second inner sidewall <NUM> extending in a direction substantially aligned with posterior-anterior axis <NUM>. First inner sidewall <NUM> and second inner sidewall <NUM> can be substantially parallel in one embodiment. As noted above, different portions of body <NUM> can include recessed areas or apertures. In one embodiment, shown best in <FIG>, first inner sidewall <NUM> and/or second inner sidewall <NUM> include a plurality of apertures <NUM>.

Furthermore, in some embodiments, first inner sidewall <NUM> and second inner sidewall <NUM> can help define or bound a central hollow region <NUM> in body <NUM>. Central hollow region <NUM> can extend through the thickness of body <NUM>. Central hollow region <NUM> can be configured to receive the blades and the blade actuating component, as will be discussed further below. In <FIG> and <FIG>, it can be seen that central hollow region <NUM> includes a main opening <NUM> and a posterior opening <NUM>, where main opening <NUM> is connected with a posterior opening <NUM> such that some components can pass from main opening <NUM> into posterior opening <NUM>. Main opening <NUM> is located toward a center or middle portion of the body, and posterior opening <NUM> is located along the posterior periphery of the body. In one embodiment, posterior opening <NUM> is significantly narrower in width across the horizontal plane relative to the width associated with main opening <NUM>.

In different embodiments, posterior opening <NUM> can be disposed between a first end portion <NUM> and a second end portion <NUM> that are associated with posterior side <NUM> of body <NUM>. Furthermore, in some embodiments, each end portion can include a recessed region. In <FIG>, a first posterior recess <NUM> is formed within a portion of first end portion <NUM> and a second posterior recess <NUM> is formed within a portion of second end portion <NUM>. As will be discussed below with respect to <FIG> and <FIG>, first posterior recess <NUM> and second posterior recess <NUM> can be configured to receive a cover.

First end portion <NUM> and a second end portion <NUM> can be substantially similar in some embodiments. In one embodiment, first end portion <NUM> and a second end portion <NUM> are mirror-images of one another relative to a central posterior-anterior axis or midline. In some embodiments, first posterior recess <NUM> and second posterior recess <NUM> are sized and dimensioned to snugly receive a rearward cover or cap that extends between or bridges together first end portion <NUM> and second end portion <NUM> of body <NUM>, providing a substantially continuous outer periphery of the implant. In addition, in some embodiments, either or both of first end portion <NUM> and second end portion <NUM> can include pin holes (shown in <FIG> as pin holes <NUM>), which can be used to help secure the cover to the posterior side of body <NUM> (see <FIG>).

The configuration of body <NUM> shown for the embodiment of <FIG> may facilitate the manufacturing process in different embodiments. In particular, this configuration may permit 3D Printing via laser or electron beam with minimal support structures by forming a unitary piece with a plurality of openings. This design may also help to improve visibility of adjacent bony anatomy under X-ray fluoroscopy while still providing sufficient structural support and rigidity to withstand all testing requirements and the clinical loading of an implant. Other embodiments, not pictured in the figures, include round or rectangular openings in otherwise solid geometry of the anterior, posterior, or lateral sides.

Embodiments can also include one or more blade retaining portions. A blade retaining portion may receive any part of a blade, including one or more edges and/or faces of the blade. In one embodiment, a body includes blade retaining portions to receive the anterior and posterior edges of each blade. As seen in <FIG>, body <NUM> includes a first blade retaining portion <NUM> positioned toward anterior side <NUM> of first inner sidewall <NUM> and a second blade retaining portion <NUM> positioned toward posterior side <NUM> of first inner sidewall <NUM>. Thus, each blade retaining portion is formed in an outer perimeter of a lateral side of main opening <NUM> of central hollow region <NUM>. First blade retaining portion <NUM> comprises a first blade retaining channel extending through the depth of body <NUM> that is configured to receive an anterior edge of the first blade (see <FIG>). Likewise, second blade retaining portion <NUM> comprises a second blade retaining channel extending through the depth of body <NUM> that is configured to receive a posterior edge of the first blade (see <FIG>).

In some embodiments, one or more channels can be oriented in a direction that is substantially diagonal relative to the horizontal plane. In one embodiment, a channel can be oriented approximately <NUM> degrees relative to the horizontal plane. In other embodiments, a channel can be oriented vertically (approximately <NUM> degrees relative to the horizontal plane) or can be oriented between <NUM> degrees and <NUM> degrees relative to the horizontal plane. The orientation of a channel can be configured to correspond to the orientation of the anterior edges and/or posterior edges of a blade in some embodiments.

Body <NUM> also includes third blade retaining portion <NUM> and fourth retaining portion <NUM> for receiving the anterior and posterior edges of the second blade. This configuration may help maximize available bone graft volume within the implant since the lateral edges of the blades serve as tracks for translation. Specifically, this limits the need for additional track members on the blade that would take up additional volume in the implant. Furthermore, the arrangement of the retaining channels and the associated blade edges results in most of the volume of the retaining channels being filled by the blade edges in the retracted position, which helps prevent any graft material or BGPM (details on the effect and use of bone growth promoting material will be discussed further below) from entering the retaining channels and inhibiting normal blade travel.

<FIG> is an isometric side view of an embodiment of blade actuating component <NUM>. A front or anterior side view of blade actuating component <NUM> is also shown in <FIG>, and a lateral side view of blade actuating component <NUM> is depicted in <FIG>. Referring to <FIG>, blade actuating component <NUM> may include a driven shaft portion <NUM> and a blade engaging portion <NUM>. Driven shaft portion <NUM> further includes a driven end <NUM> along the anterior-most end of driven shaft portion <NUM>.

In some embodiments, driven end <NUM> can include one or more engaging features. For example, driven shaft portion <NUM> can include a threaded opening <NUM> that is accessible from driven end <NUM>, as best seen in <FIG>. In some embodiments, threaded opening <NUM> may receive a tool with a corresponding threaded tip. With this arrangement, driven end <NUM> can be temporarily mated with the end of a tool (see <FIG>) used to impact blade actuating component <NUM> and drive the set of blades into adjacent vertebrae. This may help to keep both the driving tool and driven end <NUM> aligned during the impact, as well as reduce the tendency of the driving tool to slip with respect to driven end <NUM>. Using mating features also allows driven end <NUM> to be more easily "pulled" distally from implant <NUM>, which can be used to retract the blades, should it be necessary to remove the implant or re-position the blades.

In addition, driven shaft portion <NUM> can be substantially elongated and/or narrow relative to blade engaging portion <NUM>. For example, in <FIG> and <FIG>, driven shaft portion <NUM> is seen to comprise a substantially elongated rectangular prism. In other words, driven shaft portion <NUM> has a substantially rounded rectangular cross-sectional shape in the vertical plane. Furthermore, as best seen in <FIG>, blade engaging portion <NUM> has a greater width in the direction aligned with vertical axis <NUM>, and includes a generally rectangular shape with a U-shaped or wrench shaped posterior end. The size and shape of blade actuating component <NUM> allows driven shaft portion <NUM> to smoothly insert into the guide opening formed in the body (see <FIG>) while blade engaging portion <NUM> is shaped and sized to be positioned in the central opening of the body (see <FIG>) and configured to receive the blade set.

Furthermore, as will be discussed further below with respect to <FIG> and <FIG>, blade actuating component <NUM> includes provisions for securing or receiving a portion of the cover within the implant. For example, in <FIG> and <FIG>, blade actuating component <NUM> includes an actuating posterior end <NUM>, which includes a receiving portion <NUM>. Receiving portion <NUM> can be sized and dimensioned to receive, fit, or be disposed around a portion of the cover in some embodiments. In one embodiment, receiving portion <NUM> comprises a mouth <NUM> with two prongs that are spaced apart from one another along vertical axis <NUM>. In some cases, the two prongs can be spaced apart by a width that is substantially similar to the thickness of the cover.

A blade actuating component can include provisions for coupling with one or more blades. In some embodiments, a blade actuating component can include one or more channels. In the exemplary embodiment of <FIG> and <FIG>, blade engaging portion <NUM> includes a first channel <NUM> and a second channel <NUM>. First channel <NUM> may be disposed in a first side surface <NUM> of blade actuating component <NUM> while second channel <NUM> may be disposed in a second side surface <NUM> of blade actuating component <NUM>.

In addition, referring to <FIG>, it can be seen that blade engaging portion <NUM> is oriented diagonally with respect to vertical axis <NUM>. In other words, a superior end <NUM> of blade engaging portion <NUM> is offset with respect to an inferior end <NUM>, such that the two ends are not aligned relative to vertical axis <NUM> when viewed from the anterior side of the component. In some embodiments, this can allow first channel <NUM> and second channel <NUM> to be approximately aligned in the vertical direction.

<FIG> is a schematic isometric view of a distal face <NUM> of first blade <NUM>, <FIG> is a schematic isometric view of a proximal face <NUM> of first blade <NUM>, and <FIG> depicts an inferior side <NUM> of first blade <NUM>. First blade <NUM>, or simply blade <NUM>, includes an outer edge <NUM> associated with inferior side <NUM> of blade <NUM>, an inner edge <NUM> associated with a superior side <NUM>, an anterior edge <NUM> and a posterior edge <NUM>. These edges bind distal face <NUM> (i.e., a face oriented in the outwardly-facing or distal direction) and proximal face <NUM> (i.e., a face oriented in the inwardly-facing or proximal direction).

In different embodiments, the geometry of a blade could vary. In some embodiments, a blade could have a substantially planar geometry such that the distal face and the proximal face of the blade are each parallel with a common plane, as best shown in <FIG>. In other embodiments, a blade could be configured with one or more bends. In some embodiments, a blade can have a channel-like geometry (ex. "C"-shaped or "S"-shaped). In the embodiment shown in <FIG>, blade <NUM> has a U-shaped geometry with flanges. In particular, blade <NUM> a first channel portion <NUM>, a second channel portion <NUM> and a third channel portion <NUM>. Here, the first channel portion <NUM> is angled with respect to second channel portion <NUM> at a first bend <NUM>. Likewise, third channel portion <NUM> is angled with respect to second channel portion <NUM> at second bend <NUM>. Additionally, blade <NUM> includes a first flange <NUM> extending from first channel portion <NUM> at a third bend <NUM>. Blade <NUM> also includes a second flange <NUM> extending from third channel portion <NUM> at a fourth bend <NUM>. This geometry for blade <NUM> helps provide optimal strength for blade <NUM> compared to other planar blades of a similar size and thickness, and allowing for greater graft volume.

Furthermore, in some embodiments, blade <NUM> can include provisions for increasing the support or structural strength of blade <NUM>. In one embodiment, blade <NUM> includes a bridge portion <NUM> that is disposed or formed on distal face <NUM>. Referring to <FIG>, bridge portion <NUM> extends between third bend <NUM> and fourth bend <NUM>. Bridge portion <NUM> can be configured to increase the structural support of blade <NUM>. In different embodiments, bridge portion <NUM> can include features that provide a truss, brace, buttress, strut, joist, or other type of reinforcement to the curved or undulating structure of blade <NUM>. In one embodiment, bridge portion <NUM> is disposed nearer to the inner edge relative to the outer edge, such that bridge portion <NUM> is offset relative to the distal face of the blade.

In some embodiments, bridge portion <NUM> includes a relatively wide U-shaped or curved V-shaped outer sidewall <NUM>. In <FIG>, outer sidewall <NUM> extends between third bend <NUM> and fourth bend <NUM>. Furthermore, bridge portion <NUM> can have an inner sidewall (disposed on the opposite side of the bridge portion relative to the outer sidewall) that is disposed flush or continuously against the distal surfaces of first channel portion <NUM>, second channel portion <NUM>, and third channel portion <NUM>, represented in <FIG> by a U-shaped edge <NUM>. In one embodiment, the U-shape associated with the inner sidewall or edge of bridge portion <NUM> is substantially similar to the U-shape geometry of blade <NUM>.

Bridge portion <NUM> can also be substantially symmetrical in some embodiments. For example, in <FIG>, bridge portion <NUM> comprises a first triangular prism portion <NUM> joined to a second triangular prism portion <NUM> by a central curved portion. Each portion can bolster the structure of the blade, and provide resistance against the pressures applied to a blade by external forces during use of the implant. Thus, bridge portion <NUM> can improve the ability of blade <NUM> to resist external pressures and forces and/or help maintain the specific shape of blade <NUM>.

In the exemplary embodiment, the outer edge <NUM> is a penetrating edge configured to be implanted within an adjacent vertebral body. To maximize penetration, outer edge <NUM> may be sharpened so that blade <NUM> has an angled surface <NUM> adjacent outer edge <NUM>. Moreover, in some embodiments, anterior edge <NUM> and posterior edge <NUM> are also sharpened in a similar manner to outer edge <NUM> and may act as extensions of outer edge <NUM> to help improve strength and penetration. It can be understood that, in some embodiments, bridge portion <NUM> can also serve to help prevent the blades from extending further outward into a vertebra downward once they reach the desired deployment extension.

A blade can further include provisions for coupling with a blade actuating component. In some embodiments, a blade can include a protruding portion. In some embodiments, the protruding portion can extend away from a face of the blade and may fit within a channel in a blade actuating component. Referring to <FIG>, blade <NUM> includes a protruding portion <NUM> that extends from proximal face <NUM>. Protruding portion <NUM> may generally be sized and shaped to fit within a channel of the blade actuating component (i.e., first channel <NUM> shown in <FIG>). In particular, the cross-sectional shape may fit within a channel of the blade actuating component. In some cases, the cross-sectional width of protruding portion <NUM> may increase between a proximal portion <NUM> and a distal portion <NUM> allowing protruding portion <NUM> to be interlocked within a channel as discussed in detail below.

A protruding portion may be oriented at an angle on a blade so as to fit with an angled channel in a blade actuating component. In the embodiment of <FIG>, protruding portion <NUM> may be angled with respect to inner edge <NUM> such that the body of blade <NUM> is vertically oriented within the implant when protruding portion <NUM> is inserted within the first channel. In other words, the longest dimension of protruding portion <NUM> may form a protruding angle <NUM> with inner edge <NUM>.

Although the above discussion is directed to first blade <NUM>, it may be appreciated that similar principles apply for second blade <NUM>. In particular, in some embodiments, second blade <NUM> may have a substantially identical geometry to first blade <NUM>. Furthermore, while reference is made to a superior side and inferior side with respect to the first blade, it will be understood that, in some embodiments, the orientation of the second blade can differ such that the inner edge is associated with the inferior side and the outer edge is associated with the superior side.

As noted above, each blade may be associated with the blade engaging portion of the blade actuating component. In <FIG>, an exploded isometric view is shown with blade actuating component <NUM>, first blade <NUM>, and second blade <NUM>, and in <FIG>, first blade <NUM> and second blade <NUM> are assembled within blade actuating component <NUM>. It can be seen that protruding portion <NUM> of first blade <NUM> fits into first channel <NUM>. Likewise, protruding portion <NUM> of second blade <NUM> fits into second channel <NUM>. Referring to <FIG> and <FIG>, blade engaging portion <NUM> may comprise a superior surface <NUM>, an inferior surface <NUM>, a first side surface <NUM>, and a second side surface <NUM>. Here, first side surface <NUM> may be a first lateral side facing surface and second side surface <NUM> may be a second lateral side facing side surface.

Each channel that is formed in blade engaging portion <NUM> is seen to extend at an angle between superior surface <NUM> and inferior surface <NUM> of blade engaging portion <NUM>. For example, as best seen in <FIG>, first channel <NUM> has a first end <NUM> open along superior surface <NUM> and a second end <NUM> open along inferior surface <NUM>. Moreover, first end <NUM> is disposed further from driven shaft portion <NUM> than second end <NUM>. Likewise, second channel <NUM> includes opposing ends on superior surface <NUM> and inferior surface <NUM>, though in this case the end disposed at superior surface <NUM> is disposed closer to driven shaft portion <NUM> than the end disposed at inferior surface <NUM>.

In different embodiments, the angle of each channel could be selected to provide proper blade extension for varying implant sizes. As used herein, the angle of a channel is defined to be the angle formed between the channel and a transverse plane of the blade actuating component. In the embodiment of <FIG> and <FIG>, first channel <NUM> forms a first angle with transverse plane <NUM> of blade actuating component <NUM>, while second channel <NUM> forms a second angle with transverse plane <NUM>. In the exemplary embodiment, the first angle and the second angle are equal to provide balanced reactive forces as the blades are deployed. By configuring the blades and blade actuating component in this manner, each blade is deployed about a centerline (e.g., transverse plane <NUM>) of the blade actuating component, which helps minimize friction and binding loads between these parts during blade deployment. Additionally, the arrangement helps provide balanced reaction forces to reduce insertion effort and friction.

In different embodiments, the angle of each channel could vary. In some embodiments, a channel could be oriented at any angle between <NUM> and <NUM> degrees. In other embodiments, a channel could be oriented at any angle between <NUM> and <NUM> degrees. Moreover, in some embodiments, the angle of a channel may determine the angle of a protruding portion in a corresponding blade. For example, protruding angle <NUM> formed between protruding portion <NUM> and inner edge <NUM> of blade <NUM> (see <FIG>) may be approximately equal to the angle formed between first channel <NUM> and transverse plane <NUM>. This keeps the outer penetrating edge of blade <NUM> approximately horizontal so that the degree of penetration does not vary at different sections of the blade.

Furthermore, as seen in <FIG>, each channel has a cross-sectional shape that facilitates a coupling or fit with a corresponding portion of a blade. As an example, channel <NUM> has an opening <NUM> on first side surface <NUM> with an opening width <NUM>. At a location <NUM> that is proximal to opening <NUM>, channel <NUM> has a width <NUM> that is greater than opening width <NUM>. This provides a cross-sectional shape for channel <NUM> that allows for a sliding joint with a corresponding part of first blade <NUM>. In the exemplary embodiment, first channel <NUM> and second channel <NUM> are configured with dovetail cross-sectional shapes. In other embodiments, however, other various cross-sectional shapes could be used that would facilitate a similar sliding joint connection with a correspondingly shaped part. In other words, in other embodiments, any geometry for a blade and a blade actuating component could be used where the blade and blade actuating component include corresponding mating surfaces of some kind. In addition, in some embodiments, blade engaging portion <NUM> may be contoured at the superior and inferior surfaces to resist subsidence and allow maximum blade deployment depth. This geometry may also help to keep the blade engaging portion <NUM> centered between vertebral endplates. As an example, the contouring of superior surface <NUM> and inferior surface <NUM> in the present embodiment is best seen in the enlarged cross-sectional view of <FIG>.

Each channel may be associated with a first channel direction and an opposing second channel direction. For example, as best seen in <FIG>, first channel <NUM> may be associated with a first channel direction <NUM> that is directed towards superior surface <NUM> along the length of first channel <NUM>. Likewise, first channel <NUM> includes a second channel direction <NUM> that is directed towards inferior surface <NUM> along the length of first channel <NUM>.

With first protruding portion <NUM> of first blade <NUM> disposed in first channel <NUM>, first protruding portion <NUM> can slide in first channel direction <NUM> or second channel direction <NUM>. As first protruding portion <NUM> slides in first channel direction <NUM>, first blade <NUM> moves vertically with respect to blade actuating component <NUM> such that first blade <NUM> extends outwardly on a superior side of the implant to a deployed position (see <FIG>). As first protruding portion <NUM> slides in second channel direction <NUM>, first blade <NUM> moves vertically with respect to blade actuating component <NUM> such that first blade <NUM> is retracted within housing <NUM> of implant <NUM> (see <FIG>). In a similar manner, second protruding portion <NUM> of second blade <NUM> may slide in first and second channel directions of second channel <NUM> such that second blade <NUM> can be extended and retracted from implant <NUM> on an inferior side (see <FIG>). By using this configuration, blade actuating component <NUM> propels both blades in opposing directions, thereby balancing the reactive loads and minimizing cantilevered loads and friction on the guide bar.

As shown in the cross section of <FIG>, the fit between each blade and the respective channel in blade actuating component <NUM> may be configured to resist motion in directions orthogonal to the corresponding channel directions. For example, with first protruding portion <NUM> inserted within first channel <NUM>, first blade <NUM> can translate along first channel direction <NUM> or second channel direction <NUM>, but may not move in a direction <NUM> that is perpendicular to first channel direction <NUM> and second channel direction <NUM> (i.e., blade <NUM> cannot translate in a direction perpendicular to the length of first channel <NUM>). Specifically, as previously mentioned, the corresponding cross-sectional shapes of first channel <NUM> and first protruding portion <NUM> are such that first protruding portion <NUM> cannot fit through the opening in first channel <NUM> on first side surface <NUM> of blade actuating component <NUM>.

In some embodiments, each protruding portion forms a sliding dovetail connection or joint with a corresponding channel. Using dovetail tracks on the blade actuating component and corresponding dovetail features on the posterior and anterior blades allows axial movement along the angle of inclination while preventing disengagement under loads encountered during blade impaction and retraction. By preventing disengagement under loads, the dovetail connection provides a substantially rigid continuity between the superior blade, the blade actuating component, and the inferior blade. This substantially rigid continuity may provide strength, stability, and resistance to fatigue in compression, sheer, and torsion. Accordingly, this substantially rigid continuity between the superior blade, the blade actuating component, and the inferior blade may provide the similar structural benefits as a plate screwed to the vertebral bodies bridging the annulotomy, as is commonly used for spinal fusion procedures.

In <FIG>, first protruding portion <NUM> forms a sliding dovetail joint with first channel <NUM>. Of course, the embodiments are not limited to dovetail joints and other fits/joints, where the opening in a channel is smaller than the widest part of a protruding portion of a blade could be used. For example, in some embodiments, a T-shaped protrusion and corresponding slot may be used (see, e.g., <FIG>). As a further alternative, a rectangular shaped protrusion and corresponding slot may be used (see, e.g., <FIG>).

It may be appreciated that in other embodiments, the geometry of the interconnecting parts between a blade and a blade actuating component could be reversed. For example, in another embodiment, a blade could comprise one or more channels and a blade actuating component could include corresponding protrusions to fit in the channels. In such embodiments, both the protruding portion of the blade actuating component and the channels in the blades could have corresponding dovetail geometries.

As discussed above with respect to <FIG>, embodiments of implant <NUM> can include a cover <NUM> that is configured to close or bridge the posterior opening of body <NUM> and help secure the various components of implant <NUM> together. <FIG> is a schematic isometric superior-side view of an embodiment of cover <NUM>, and is a schematic isometric inferior-side view of an embodiment of cover <NUM>. Referring to <FIG>, cover <NUM> includes one or more openings for engaging different parts of implant <NUM>. For example, cover <NUM> may include a first pin hole <NUM> and a second pin hole <NUM> that are configured to receive a first pin and a second pin, respectively (see <FIG>). Each pin hole can comprise a through-hole that extends from the superior surface to the inferior surface of cover <NUM>, though in other embodiments pin holes can be blind holes. Moreover, first pin hole <NUM> and second pin hole <NUM> (shown in <FIG>) of cover <NUM> may be aligned with corresponding holes in the body, as discussed below.

<FIG> is a schematic isometric exploded view of body <NUM> and cover <NUM>. <FIG> is a schematic isometric assembled view of body <NUM> and cover <NUM>, together forming housing <NUM> of implant <NUM>. Specifically, in some embodiments, cover <NUM> can be inserted into the recesses associated with a posterior end <NUM> of body <NUM>. In addition, first pin hole <NUM> and second pin hole <NUM> shown in <FIG> can be aligned with the pin receiving openings of body <NUM> comprising between two and four through-hole channels in posterior end <NUM>. In <FIG>, first end portion <NUM> includes a third pin hole <NUM> in a superior portion of first end portion <NUM> and a fourth pin hole <NUM> in an inferior portion of first end portion <NUM>. Similarly, second end portion <NUM> includes a fifth pin hole <NUM> in a superior portion of second end portion <NUM> and a sixth pin hole <NUM> in an inferior portion of second end portion <NUM>. When cover <NUM> is received by body <NUM>, as shown in <FIG>, third pin hole <NUM> and the fourth pin hole are aligned with the first pin hole of cover <NUM>, and fifth pin hole <NUM> and the sixth pin hole are aligned with the second pin hole of cover <NUM>. Other embodiments may have a fewer or greater number of pin holes. In some embodiments, body <NUM> may only include third pin hole <NUM> and fifth pin hole <NUM>, for example. Once cover <NUM> has been inserted into body <NUM>, first pin <NUM> and second pin <NUM> (see <FIG>) can be inserted into the two sets of pin holes to fasten or secure the body to the cover.

As noted above, the embodiments described herein provide an implant that can move from a first position (the "insertion position"), which allows the implant to maintain a low profile, to a second position (the "impaction position" or the "deployed position"), that deploys the blades and inserts them into the proximal superior and inferior vertebral bodies. While the implant is in the first (insertion) position, the blades of the device may be retracted within the body of the implant (i.e., the blades may themselves be in a "retracted position"). In the second (deployed) position of the implant, the blades extend superiorly (or cranially) or inferiorly (or caudally) beyond the implant and into the vertebral bodies to prevent the implant from moving out of position over time. Thus, the blades themselves may be said to be in an "extended position" or "deployed position". When the blades are deployed, the implant resists left to right rotation and resists flexion and/or extension. It may be appreciated that, although the blades may approximately move in vertical directions (i.e., the superior and inferior directions), the actual direction of travel may vary from one embodiment to another. For example, in some embodiments the blades may be slightly angled within the implant and may deploy at slight angles relative to a vertical direction (or to the inferior/superior directions).

<FIG>, <FIG>, and <FIG> illustrate several views of implant <NUM> in different operating modes or operating positions. Specifically, <FIG> is a schematic isometric anterior side view of implant <NUM> in an insertion position.

<FIG> is a schematic isometric posterior side view of implant <NUM> in the same insertion position of <FIG>. Referring to <FIG>, in the insertion position, driven end <NUM> of blade actuating component <NUM> may be disposed distal to the chamber portion of body <NUM> (i.e., a portion of blade actuating component <NUM> is disposed or extends through the chamber portion). With implant <NUM> in the insertion position, first blade <NUM> and second blade <NUM> are retracted within housing <NUM>. Thus, as best seen in <FIG> and <FIG>, neither first blade <NUM> nor second blade <NUM> extend outwardly (distally) from superior side <NUM> or inferior side <NUM>, respectively, of implant <NUM>. In this insertion position, implant <NUM> has a compact profile and can be more easily maneuvered into place in the excised disc space between adjacent vertebrae.

<FIG> is a schematic isometric view of implant <NUM> in a deployed position. <FIG> is a schematic anterior side view of implant <NUM> in the same deployed position of <FIG>. <FIG> is a schematic lateral side view of implant <NUM> in the same deployed position of <FIG>. Referring to <FIG>, in the deployed position, driven end <NUM> of blade actuating component <NUM> may be disposed proximally to an anterior opening <NUM> formed in the outer periphery of body <NUM> (i.e., the entirety of blade actuating component <NUM> is disposed within implant <NUM>). With implant <NUM> in the deployed position, first blade <NUM> and second blade <NUM> are extended outwards from superior side <NUM> and inferior side <NUM>, respectively, so as to be inserted into adjacent vertebral bodies. Furthermore, each blade remains positioned in the central hollow region of the body in both the retracted and extended positions. For example, an inner edge of each blade is disposed in a central hollow region of the housing in the retracted position, and the inner edge of the blade remains in the central hollow region in the extended position.

In some embodiments, one or more blades could be deployed at a slight angle, relative to the normal directions on the superior and inferior surfaces of the implant. In some embodiments, one or more blades could be oriented at an angle between <NUM> and <NUM> degrees. In other embodiments, one or more blades could be oriented at an angle that is greater than <NUM> degrees. In the exemplary embodiment shown in <FIG>, first blade <NUM> and second blade <NUM> are both oriented at a slight angle from normal axis <NUM>. Specifically, first blade <NUM> forms a first angle <NUM> with normal axis <NUM> and second blade <NUM> forms a second angle <NUM> with normal axis <NUM>. In one embodiment, first angle <NUM> and second angle <NUM> are both approximately <NUM> degrees. Angling the blades in this way may help keep first blade <NUM> and second blade <NUM> approximately centered in the adjacent vertebrae upon deployment. In an exemplary embodiment, the common anterior implant blade angle is chosen to keep the blades close to the centerline of the vertebral body to minimize rotational loads on the vertebral bodies during blade deployment, and also to provide an optional cover plate screw clearance. In addition, it can be seen in <FIG> that the outer edge of each blade is positioned toward a central region of the implant when the blade is deployed, such that the outer edge is positioned centrally relative to the housing in the extended position.

The extension of each blade could vary in different embodiments. In some embodiments, a blade could extend outwardly by a length between <NUM>% and <NUM>% of the depth of an implant. In still other embodiments, combined blade height could extend outwardly by a length between <NUM>% and <NUM>% of the depth of an implant. In the exemplary embodiment shown in <FIG>, first blade <NUM> and second blade <NUM> combined may be coverable of extending outwardly from implant <NUM> by an amount equal to <NUM>% of the depth of implant <NUM>. This can be done while still keeping the blades fully retracted within implant <NUM> since the blades are guided by two robust parallel tracks in body <NUM> and also by angled cross channels in blade actuating component <NUM>, thus constraining all six axes of motion. In other embodiments, the combined blade height at deployment could be less than <NUM>%. In one embodiment, the implant could be designed so that the combined blade height is less than <NUM> to reduce the risk of fracturing the adjacent vertebral bodies. In another embodiment, the implant has a combined blade height of <NUM> or less.

Furthermore, as disclosed in the "Implant With Deployable Blades" application, in some embodiments, implant <NUM> can use a three-point attachment configuration for each of first blade <NUM> and second blade <NUM>. Specifically, each blade is received along its lateral edges by two blade retaining portions, and also coupled to blade actuating component <NUM>, using the dovetail connection described above. In other words, anterior edge <NUM> of first blade <NUM> is received within the first blade retaining channel of first blade retaining portion <NUM>. Posterior edge <NUM> of first blade <NUM> is received within a second retaining channel of second blade retaining portion <NUM>. Moreover, distal face <NUM> of first blade <NUM> remains unattached to any other elements of implant <NUM>. Not only does first blade <NUM> remain unattached along distal face <NUM>, but the entirety of distal face <NUM> between anterior edge <NUM> and posterior edge <NUM> is spaced apart from (i.e., not in contact with) all other elements of implant <NUM>. Further, second blade <NUM> is likewise attached at its lateral edges to corresponding blade retaining portions, and also coupled to blade actuating component <NUM> using a sliding dovetail connection. Thus, first blade <NUM> and second blade <NUM> are held in implant <NUM> using a three-point attachment configuration that may limit unwanted friction on first blade <NUM> and second blade <NUM> during impaction. It may be appreciated that the fit between each blade and each blade retaining channel may provide sufficient clearance to allow for translation of the blades along the retaining channels. In other words, the fit may not be so tight as to impede movement of the lateral edges within the retaining channels.

In different embodiments, the cross-sectional geometry of channels in one or more blade retaining portions could vary. In some embodiments, the cross-sectional geometry could be rounded. In the embodiments disclosed herein, first blade retaining portion <NUM> (see <FIG>) has a rectangular blade retaining channel. This rectangular geometry for the blade tracks or channels and tolerance allows for precise axial travel without binding from actuation ramp angular variations. In some embodiments, the posterior edge and anterior edge of each blade may remain in the tracks or channels of each blade retaining portion while the blades are retracted to prevent bone graft material from restricting free deployment of the blades.

Using an interlocking joint, such as a dovetail sliding joint, to connect the blades and a blade actuating component helps prevent the blades from decoupling from the blade actuating component during impact. Additionally, with an interlocking joint the blade actuating component can be used to retract the blades.

<FIG> illustrate several schematic views of implant <NUM> during an impact sequence (<FIG>) as well as during a step of retracting the blades (<FIG>). In <FIG>, housing <NUM> of implant <NUM> is shown in phantom to better show blade actuating component <NUM>, first blade <NUM> and second blade <NUM>. Also, each of <FIG> include cross-sectional views of a section of blade actuating component <NUM>, first blade <NUM> and second blade <NUM> to better illustrate the coupling between these parts during actuation.

In <FIG>, implant <NUM> is in the insertion position, with first blade <NUM> and second blade <NUM> fully retracted within housing <NUM>. Next, as seen in <FIG>, an impacting force <NUM> is applied to driven end <NUM> of blade actuating component <NUM>. As blade actuating component <NUM> is translated towards posterior side <NUM> of implant <NUM>, blade actuating component <NUM> applies forces to first blade <NUM> and second blade <NUM> along first channel <NUM> and second channel <NUM>, respectively. Specifically, the orientation of first channel <NUM> is such that first blade <NUM> is forced towards the inferior side of implant <NUM>. Likewise, the orientation of second channel <NUM> is such that second blade <NUM> is forced towards the superior side of implant <NUM>. However, in other embodiments, the channel orientations can be switched such that first blade <NUM> is forced towards the inferior side of implant <NUM> and second blade <NUM> is forced towards the superior side of implant <NUM>.

Furthermore, the interlocking connection between first protruding portion <NUM> and first channel <NUM> (as well as between second protruding portion <NUM> and second channel <NUM>) means that both blades remain coupled to the motion of blade actuating component <NUM> at all times. It should be noted that since both blades are restricted from moving in a longitudinal direction, the resulting motion of each blade is purely vertical. Moreover, using the dovetail-shaped protruding portions for each blade means the protruding portions are both lifting at the center line to limit any cocking force or rotational moments that could result in increased (friction) resistance to motion or binding of these moving parts.

Using this configuration, the forces deploying the blades are balanced through the blade actuating component <NUM> in order to minimize friction and binding between driven shaft portion <NUM> and the guide opening in body <NUM> (see <FIG>), which helps to guide blade actuating component <NUM> and keep its motion restricted to directions parallel to the longitudinal axis (see <FIG>).

In <FIG>, implant <NUM> has been placed in the fully deployed position, with both first blade <NUM> and second blade <NUM> fully extended from implant <NUM>. As seen in the cross-sectional view, both first blade <NUM> and second blade <NUM> remain coupled with blade actuating component <NUM> when implant <NUM> is in the fully deployed position. Because of this coupling, the motion of blade actuating component <NUM> can be reversed to retract first blade <NUM> and second blade <NUM>, as shown in <FIG>.

It may be appreciated that in some embodiments a blade actuating component (e.g., blade actuating component <NUM>) may function to support adjacent vertebral bodies. This is can be accomplished by using a blade actuating component with a height similar to the height of the outer support structure so that the superior and inferior surfaces of the blade actuating component may come into contact with the vertebral bodies following implantation. Since the blade actuating component functions as a load bearing structure within the implant, this may free up additional space in the implant otherwise occupied by additional support structures, thereby increasing the internal volume available for bone graft or BGPMs.

Referring to <FIG>, driven end <NUM> of blade actuating component <NUM> may be pulled in an opposing direction to the motion shown in <FIG>. For example, in some embodiments a delivery tool can be coupled to driven end <NUM> using a threaded connector. Then, as the tip of the delivery tool is retracted, a retracting or pulling force <NUM> may be applied to drive end <NUM>. As blade actuating component <NUM> (and specifically, blade engaging portion <NUM>) is pulled towards anterior side <NUM> of implant <NUM>, blade actuating component <NUM> applies forces to first blade <NUM> and second blade <NUM> along first channel <NUM> and second channel <NUM>, respectively. Specifically, the orientation of first channel <NUM> is such that first blade <NUM> is forced towards the superior side of implant <NUM>. Likewise, the orientation of second channel <NUM> is such that second blade <NUM> is forced towards the inferior side of implant <NUM>. Although not shown, applying sufficient force at driven end <NUM> may result in full retraction of first blade <NUM> and second blade <NUM> so that implant <NUM> is returned to the insertion position shown in <FIG>.

As noted above, body <NUM> may include guide opening <NUM> that receives a portion of blade actuating component <NUM>. When the implant is in the deployed position, the driven shaft portion can be disposed securely in the chamber portion. In some embodiments, the chamber portion of guide opening <NUM> may have a shape that matches the cross-sectional shape of a driven shaft portion of a blade actuating component. In some embodiments, both the chamber portion and the driven shaft portion of the blade actuating component have rectangular cross-sectional shapes (see <FIG> and <FIG>). This configuration may allow axial motion, but control rotational and angular loads that could result during blade impaction.

<FIG> illustrate two schematic views of locking screw <NUM>, according to an embodiment. Locking screw <NUM> can be a type of threaded fastener in some embodiments. In <FIG>, locking screw <NUM> includes a flanged head <NUM> with a threaded segment portion <NUM> and further includes a substantially smooth and elongated body portion <NUM>. Threaded segment portion <NUM> is sized and dimensioned to engage with the grooved portion of the body (see <FIG> below). Flanged head <NUM> can also include a receiving recess <NUM> which can engage with a driving tool in order to secure the locking screw within the implant. Thus, although body portion <NUM> is disposed within threaded opening of the blade actuating component when the screw lock is secured, body portion <NUM> need not engage or lock with the threading associated with the threaded opening.

Implant <NUM> can include provisions for securing the implant <NUM> in the deployed position. Referring to the exploded isometric view of <FIG>, guide opening <NUM> can include a grooved portion <NUM> that is formed directly adjacent to the chamber portion. Grooved portion <NUM> can have a round cross-sectional shape in the vertical plane, and has a wider diameter relative to the diameter or width of the chamber portion. The diameter of grooved portion <NUM> can be configured to mate with the diameter of the flanged head. In one embodiment, grooved portion <NUM> is disposed directly adjacent to the outermost anterior periphery of guide opening <NUM>. As locking screw <NUM> is inserted into the anterior side of guide opening <NUM> (see <FIG>), threaded segment portion <NUM> that extends around flanged head <NUM> of locking screw <NUM> can engage with grooved portion <NUM>, securing locking screw <NUM> to body <NUM>. When in this position, body portion <NUM> of locking screw <NUM> can also be disposed through the passageway of threaded opening <NUM> of blade actuating component <NUM>. As shown best in the partial cross-sectional view of <FIG>, when implant <NUM> is in the deployed position, a portion of driven shaft portion <NUM> is disposed within chamber <NUM> of guide opening <NUM>, primarily comprising the portion of driven shaft portion <NUM> that includes threaded opening <NUM>. Furthermore, flanged head <NUM> of locking screw <NUM> extends from anterior opening <NUM> through grooved portion <NUM>, and body portion <NUM> of locking screw <NUM> extends through threaded opening <NUM> of driven shaft portion <NUM>. Flanged head <NUM> is prevented from moving further into guide opening <NUM> because of the larger diameter of flanged head <NUM> relative to body portion <NUM>. Thus, it can be understood that the insertion of the implant and the deployment of the blades of the implant occur through the engagement of an insertion tool within only a single guide opening <NUM>, improving surgical efficiency and safety.

In different embodiments, an implant can utilize different types of components to provide the features and functions described herein. In some embodiments, the features of a blade actuating component can be adjusted in order to facilitate the use of an implant with a variety of surgical requirements. For example, in some embodiments, an alternate embodiment of a second blade actuating component ("second actuating component") <NUM> can be placed within the housing of the body, as shown in <FIG>. In <FIG>, second actuating component <NUM> is configured with a receiving portion <NUM> with a mouth <NUM> that is greater in width than the embodiment of the actuating blade component presented above. Adjustments to the size of a mouth in the receiving portion of a blade actuating component can correspond to changes in the dimensions or shape of a cover, bridge piece, or cap that is used in the implant.

In addition, to allow an implant to withstand varying forces and work with different blade types, the height and/or other dimensions of the blade engaging portion can be increased or decreased. For example, in <FIG>, blade actuating component <NUM> has a first maximum height <NUM>, and in <FIG>, second actuating component <NUM> has a second maximum height <NUM>. First maximum height <NUM> is less than second maximum height <NUM>, such that blade actuating component <NUM> can be inserted into a smaller region of the human body. However, when the blades being used must be increased in size, the greater height of second actuating component <NUM> provides the structural support to the device. In addition, second actuating component <NUM> includes diagonal portions <NUM> disposed toward the center of the actuating component that can extend the length of channels <NUM> and support additional blade weight. In some embodiments, diagonal portions <NUM> are integrally formed with second actuating component <NUM>. In addition, diagonal portions <NUM> can add a curved or sloped interface to the actuating component relative to blade actuating component described earlier (see <FIG>) in which the intersection between drive shaft portion <NUM> and blade engaging portion <NUM> is substantially perpendicular.

In order to provide greater detail with respect to the initial insertion position and the deployed position, <FIG> and <FIG> provide two cross-sectional views of the implant prior to the application of an impacting force (see <FIG>) and subsequent to the application of the impacting force. It should be noted that while <FIG> and <FIG> employ second actuating component <NUM>, the general operation and transition from insertion to deployment of implant <NUM> remains substantially the same to the process described above with respect to blade actuating component <NUM>. In <FIG>, second actuating component <NUM> is disposed such that driven end <NUM> extends distally outward and away from an anterior end <NUM> of body <NUM>. The remainder of second actuating component <NUM> is positioned such that it is offset relative to the interior space of the implant along posterior-anterior axis <NUM>. In other words, the majority of blade engaging portion <NUM> is disposed nearer to anterior end <NUM> than to posterior end <NUM> of body <NUM> in the insertion position.

However, when an impacting force is applied to driven end <NUM>, the substantial entirety of second actuating component <NUM> can be disposed within the internal space of the body. Furthermore, actuating posterior end <NUM> can move translationally from the main opening of the central hollow region in body <NUM> toward the posterior opening. It can be seen that a portion of posterior opening <NUM> is filled with or bridged by a central portion of cover <NUM>. As actuating posterior end <NUM> approaches the posterior opening, receiving portion <NUM> comprising the two-pronged mouth shown in <FIG> can slide or be positioned above the superior surface and below the inferior surface of cover <NUM>, helping to secure the assembly in place and forming a continuous outer surface.

Furthermore, as noted above, in <FIG> it can be seen that threaded opening <NUM> of driven shaft portion <NUM> can be configured to receive a threaded driving tool. In addition, as shown in <FIG>, threaded flanged head <NUM> of the locking screw engages with grooved portion <NUM> formed in the structure of body <NUM>, and the locking screw body is smoothly inserted within the channel provided by threaded opening <NUM>. Driven end <NUM> can be positioned directly adjacent to the posterior end of grooved portion <NUM> when implant <NUM> is in the deployed position. In other words, once implant <NUM> is in the deployed position, driven end <NUM> is disposed such that it is spaced apart from the outer opening formed in body <NUM> by the region comprising grooved portion <NUM>.

As noted above, embodiments of implant <NUM> can make use of features or structures disclosed in the "Insertion Tool For Implant And Methods of Use" application. In some embodiments, implant <NUM> can be configured for use with a single tool that can significantly facilitate the implantation process. For example, whether a surgeon approaches the disc space from an anterior approach can be dependent on how comfortable the surgeon is with the anterior approach and operating around the aorta and vena cava. By approaching a patient from the anterior side, there can be a risk of vessel injury, as the aorta and vena cava lie in front of the spine. However, the benefits of added stability and fusion area very often outweigh the risks of the extra surgery, and the process of deployment provided herein can help lower such risks.

In some embodiments, body <NUM> may include attachment points for an insertion instrument. In <FIG> and <FIG>, a portion of an insertion tool <NUM> is shown with implant <NUM>. In <FIG>, insertion tool <NUM> is shown as it holds or grasps implant <NUM>. In <FIG>, the same view of <FIG> is shown in a partial cross-section to reveal the engagement of a threaded driver <NUM> in guide opening <NUM>.

Body <NUM> may include provisions for interacting with insertion tool <NUM>. For example, as seen in <FIG>, body <NUM> may include a first cavity <NUM> and a second cavity <NUM> (where first cavity <NUM> refers to first aperture <NUM> as identified in <FIG>). Each of first cavity <NUM> and second cavity <NUM> may receive the ends of an insertion tool <NUM> to improve the grip of the tool on implant <NUM> during insertion into (or removal from) between the vertebrae of the spine. Furthermore, the same insertion tool <NUM> can be utilized to transition implant <NUM> from the insertion position to the deployed position. As shown in <FIG> and <FIG>, insertion tool <NUM> can be used to grasp the implant body. While the implant body is grasped by two gripping jaws <NUM>, the blade actuating component can be controlled and/or driven by threaded driver <NUM>. This arrangement can maintain the blades in a retracted position during implant insertion and transfers the impact loads from the surgeon when the threaded cover is removed from the proximal end. Thus, the insertion step, deployment step, and locking screw insertion step can occur through the use of a single tool, and through interaction primarily with only the anterior facing side of the implant. Furthermore, as blade actuating component is pushed inward or outward, there is rotation associated with the threaded driver. The use of insertion tool <NUM> and the single guide opening <NUM> allows the rotation to be generally enclosed or shielded within the jaws of the insertion tool. This process can serve to reduce the risks associated with the insertion of various foreign objects into the patient.

In different embodiments, the size of an implant could vary. In some embodiments, an implant could have any length. Embodiments could have lengths ranging from <NUM> to <NUM>. In some cases, a manufacturer could provide multiple implant options with lengths varying between <NUM> and <NUM> in <NUM> increments. In some embodiments, an implant could have any height. Embodiments could have a height ranging from <NUM> to <NUM>. In some cases, a manufacturer could provide implants with heights varying from <NUM> to <NUM> in <NUM> increments. Embodiments could have widths (i.e., size along the posterior-anterior axis) of <NUM>, <NUM>, <NUM> as well as other sizes.

Embodiments can also be constructed with various lordosis angles, that is, angles of incline between the posterior and anterior sides. Embodiments could be configured with lordosis angles of <NUM>, <NUM> and <NUM> degrees, for example. In other embodiments, other lordosis angles could be used for an implant. Furthermore, in some embodiments, the blades can be angled to accommodate additional implants or other implanted devices in the spine that are located at adjacent levels, fostering stabilization in the patient's system.

Embodiments may optionally include one or more alignment features. Exemplary alignment features include, but are not limited to, windows for fluoroscopy positioning, windows for blade deployment validation, windows for aligning a blade actuating component with one or more blades, as well as various other kinds of alignment features. Referring to <FIG>, body <NUM> of implant <NUM> includes a central alignment window (referred to as fourth aperture <NUM> in <FIG>). Additionally, as shown in <FIG>, blade <NUM> includes an alignment window <NUM>. Alignment window <NUM> may align with the central alignment window when blade <NUM> is fully retracted. Moreover, blade actuating component <NUM> includes an actuating alignment window <NUM>, as shown in <FIG>. Actuating alignment window <NUM> may align with the implant body center line when the first blade and the second blade are fully deployed or fully retracted. One or more of these windows (i.e., the central alignment window or actuating alignment window <NUM>) may also facilitate fluoroscopy positioning and may be used to confirm blade deployment. For example, in some cases, when the first blade and the second blade are fully deployed, the blades may clear actuating alignment window <NUM> of blade actuating component <NUM>.

In some embodiments, the dovetail connections can help to more precisely control the blade position in both directions. Some embodiments of the implant may also include one or more stroke limiting stops. For example, there may be two stroke limiting stops formed on blade actuating component <NUM>. These stops may help to prevent over travel of blade actuating component <NUM>. Specifically, a stroke limiting stop may contact the internal surfaces of body <NUM>. In other words, the blade actuating component has a limited stroke dictated by the length of its distal portion and the inside depth of the implant, measured from the inside of the implant proximal wall and the inside surface of the cover that is pinned in place.

Some embodiments may use a bone growth promoting material, including bone graft or bone graft substitute material. As used herein, a "bone growth promoting material" (BGPM) is any material that helps bone growth. Bone growth promoting materials may include provisions that are freeze dried onto a surface or adhered to the metal through the use of linker molecules or a binder. Examples of bone growth promoting materials are any materials including bone morphogenetic proteins (BMPs), such as BMP-<NUM>, BMP-<NUM>, BMP-<NUM>, BMP-<NUM>, and BMP-<NUM>. These are hormones that convert stem cells into bone forming cells. Further examples include recombinant human BMPs (rhBMPs), such as rhBMP-<NUM>, rhBMP-<NUM>, and rhBMP-<NUM>. Still further examples include platelet derived growth factor (PDGF), fibroblast growth factor (FGF), collagen, BMP mimetic peptides, as well as RGD peptides. Generally, combinations of these chemicals may also be used. These chemicals can be applied using a sponge, matrix or gel.

Some bone growth promoting materials may also be applied to an implantable prosthesis through the use of a plasma spray or electrochemical techniques. Examples of these materials include, but are not limited to, hydroxyapatite, beta tri-calcium phosphate, calcium sulfate, calcium carbonate, as well as other chemicals.

A bone growth promoting material can include, or may be used in combination with a bone graft or a bone graft substitute. A variety of materials may serve as bone grafts or bone graft substitutes, including autografts (harvested from the iliac crest of the patient's body), allografts, demineralized bone matrix, and various synthetic materials.

Some embodiments may use autograft. Autograft provides the spinal fusion with calcium collagen scaffolding for the new bone to grow on (osteoconduction). Additionally, autograft contains bone-growing cells, mesenchymal stem cells and osteoblast that regenerate bone. Lastly, autograft contains bone-growing proteins, including bone morphogenic proteins (BMPs), to foster new bone growth in the patient.

Bone graft substitutes may comprise synthetic materials including calcium phosphates or hydroxyapatites, stem cell containing products which combine stem cells with one of the other classes of bone graft substitutes, and growth factor containing matrices such as INFUSE® (rhBMP-<NUM>-containing bone graft) from Medtronic, Inc.

It should be understood that the provisions listed here are not meant to be an exhaustive list of possible bone growth promoting materials, bone grafts or bone graft substitutes.

In some embodiments, BGPM may be applied to one or more outer surfaces of an implant. In other embodiments, BGPM may be applied to internal volumes within an implant. In still other embodiments, BGPM may be applied to both external surfaces and internally within an implant.

The various components of an implant may be fabricated from biocompatible materials suitable for implantation in a human body, including but not limited to, metals (e.g. titanium, titanium alloy, stainless steel, cobalt-chrome, or other metals), synthetic polymers (e.g. PEEK or PEKK), ceramics, and/or their combinations, depending on the particular application and/or preference of a medical practitioner.

Generally, the implant can be formed from any suitable biocompatible, non-degradable material with sufficient strength. Typical materials include, but are not limited to, titanium, biocompatible titanium alloys (e.g. Titanium Aluminides (including gamma Titanium Aluminides), Ti<NUM>-Al<NUM>-V ELI (ASTM F <NUM> and ASTM F <NUM>), or Ti<NUM>-Al<NUM>-V (ASTM F <NUM>, ASTM F <NUM>, and ASTM F <NUM>) and inert, biocompatible polymers, such as polyether ether ketone (PEEK) (e.g. PEEK-OPTIMA®, Invibio Inc. , Zeniva®, Solvay Inc. , or others). Optionally, the implant contains a radiopaque marker to facilitate visualization during imaging when constructed of radiolucent biomaterials.

In different embodiments, processes for making an implant can vary. In some embodiments, the entire implant may be manufactured and assembled via traditional and CNC machining, injection-molding, cast or injection molding, insert-molding, co-extrusion, pultrusion, transfer molding, overmolding, compression molding, <NUM>-Dimensional (<NUM>-D) printing, dip-coating, spray-coating, powder-coating, porous-coating, milling from a solid stock material and their combinations.

In one embodiment, body <NUM> may be produced by additive manufacturing. Specifically, body <NUM> may be produced using Direct Metal Laser Sintering (DMLS) using powder Ti-6Al-4V ELI, and then traditional or CNC machining in specific locations to precise dimensions. Moreover, in one embodiment, as shown in <FIG>, blade actuating component <NUM>, first blade <NUM>, second blade <NUM>, cover <NUM>, pins <NUM> and locking screw <NUM> may also be made of a material including titanium.

<FIG> is a schematic perspective anterior view of an implant according to another embodiment. In some cases, the implant shown in <FIG> may be formed at least in part from polyether ether ketone (PEEK). Because PEEK has different physical properties than metals, such as titanium, the PEEK components of the implant can be reinforced to provide the desired structural characteristics. In some embodiments, the peripheral frame of the implant may be a solid body, as opposed to a lattice or truss structure. Also, in some embodiments, additional portions of the peripheral frame may be configured to abut the blades to resist expulsion forces. Also, the implant may include one or more radiopaque markers disposed in the PEEK sections of the implant. Such radiopaque markers may be formed of any suitable radiopaque material. In some embodiments, the radiopaque markers may be formed of tantalum. Further, the insertion tool receiving recesses may be formed in portions of the implant that are reinforced. For example, in some embodiments, a lip portion for engaging the insertion tool may have a thickness that has substantially the same dimension as the recess.

<FIG> shows an intervertebral fusion implant <NUM>. Implant <NUM> may include a housing <NUM>. Housing <NUM> may have a peripheral frame <NUM>. Peripheral frame <NUM> may include an inner edge <NUM> defining a central opening <NUM> in a central portion of implant <NUM>. As shown in <FIG>, Implant <NUM> may have an anterior side <NUM>, a posterior side <NUM>, a first lateral side <NUM>, a second lateral side <NUM>, a superior side <NUM>, and an inferior side <NUM>.

Implant <NUM> may also include extendable blades configured to engage with vertebrae adjacent to implant <NUM> when implanted. The extendable blades may have a configuration similar to the blades in other embodiments discussed above. As shown in <FIG>, the blades may include a first blade <NUM> located within central opening <NUM>. First blade <NUM> may have a retracted position in housing <NUM>, in which first blade <NUM> does not extend beyond superior side <NUM>. First blade <NUM> may also have an extended position where first blade <NUM> extends outwardly from housing <NUM>. Implant <NUM> may include a blade actuating component <NUM> configured to be translated to move the blades between the retracted position and the extended position. The blade actuating component <NUM> may include a driven shaft portion and a blade engaging portion (see <FIG>, and discussion above regarding the blade actuating component in other embodiments).

As shown in <FIG>, peripheral frame <NUM> may include a first end (e.g., anterior side <NUM>) having a threaded opening <NUM> and a guide opening adjacent threaded opening <NUM>. The guide opening may receive a driven end of blade actuating component <NUM>. Implant <NUM> may include a locking screw <NUM>, which may be secured within threaded opening <NUM>. Locking screw <NUM> can be rotated between an unlocked rotational stop position, in which the driven end of blade actuating component <NUM> can pass through the guide opening, and into a locked rotational stop position, in which the drive end of blade actuating component <NUM> is prevented from moving through the guide opening.

As shown in <FIG>, implant <NUM> may further include a pin <NUM> that extends through peripheral frame <NUM> and engages with a rotation constraining groove <NUM> of locking screw <NUM>. The threaded portion of locking screw <NUM> may include a rotation constraining groove <NUM>, wherein rotation constraining groove <NUM> includes a first groove end and a second groove end. Rotation constraining groove <NUM> may extend less than one full rotation around the circumference of the threaded portion of locking screw <NUM>. Pin <NUM> may extend partially through peripheral frame <NUM> and engage rotation constraining groove <NUM> to prevent removal of locking screw <NUM> in order to secure blade actuating component <NUM> within peripheral frame <NUM> of implant <NUM>. The configuration of pin <NUM> and locking screw <NUM> is further shown and described in <CIT>, currently <CIT> and titled "Implant With Deployable Blades,".

In some embodiments, the implant may be provided with a significant lordotic angle. That is, the housing may be formed with a lordotic angle configured for implantation between vertebrae. Intervertebral implants can be subjected to forces that drive the implant in an anterior direction. As these forces drive the implant in a direction that would expel the implant from its location between the vertebrae, these are referred to as "expulsion forces. " The extendable blades disclosed herein may anchor the implant in place to prevent expulsion of the implant from its implanted location.

Implants having lordotic angles increase the magnitude of the expulsion forces imparted on the implant. The greater the lordotic angle, the greater the expulsion forces tend to be. <FIG> is a schematic lateral view of the implant shown in <FIG>. As shown in <FIG>, implant <NUM> may have a lordotic angle <NUM>. In some embodiments, the implant may have a lordotic angle in the range of <NUM>-<NUM> degrees. In some embodiments, the implant may have a lordotic angle of greater than <NUM> degrees. <FIG> also shows a second blade <NUM> extending from inferior side <NUM> of implant <NUM>.

Under expulsion loading, an intervertebral implant is driven in an anterior direction, while the blades remain held in place, as they are anchored in the adjacent vertebrae. Accordingly, the extendable blades are loaded in a posterior direction with respect to the peripheral frame of the implant. Therefore, expulsion forces push the blades against the posterior edge of the central opening in the peripheral frame.

It may be desirable to configure the PEEK housing of the implant to distribute the loading between the blades and the peripheral frame due to expulsion forces. Further, in some embodiments, the disclosed implant may have larger lordotic angles. The configuration of the PEEK peripheral frame may also distribute the increased loading due to the larger lordotic angles. In some embodiments, the tolerances between the peripheral frame and the blades may be configured to facilitate contact with a greater surface area of the blades under expulsion loading. The greater contact area may distribute the forces on the PEEK housing, thus reducing the pressure applied to the housing.

In order to distribute expulsion forces applied to the housing, additional portions of the peripheral frame may be configured to abut the blades. <FIG> is a schematic perspective posterior view of the implant shown in <FIG>. As shown in <FIG>, first blade <NUM> may include a first portion having a posterior facing surface <NUM> extending in a lateral direction and a second portion extending perpendicular to the first portion in a posterior direction to a posterior terminal end <NUM>. In some embodiments, the inner edge of peripheral frame <NUM> may include a posterior edge <NUM> configured to support first blade <NUM> against expulsion forces in two locations. For example, as shown in <FIG>, posterior edge <NUM> is configured to support first blade <NUM> at posterior facing surface <NUM> of the first portion and posterior terminal end <NUM> of the second portion of first blade <NUM>. As shown in <FIG>, contact between posterior edge <NUM> and posterior facing surface <NUM> of first blade <NUM> occurs at a first interface <NUM>. As further shown in <FIG>, contact between posterior edge <NUM> and posterior terminal end <NUM> of first blade <NUM> occurs at a second interface <NUM>.

<FIG> is a schematic superior view of a posterior portion of the implant shown in <FIG>. <FIG> shows first interface <NUM> and second interface <NUM> from a superior, enlarged view.

In some embodiments in which the housing is formed of PEEK, the implant may include one or more radiopaque markers. As shown in <FIG>, implant <NUM> may include at least one radiopaque marker <NUM> embedded in a portion of housing <NUM>.

As further shown in <FIG>, in some embodiments, first radiopaque marker <NUM> may be located in peripheral frame <NUM> of housing <NUM>. For example, first radiopaque marker <NUM> may be disposed proximate a peripheral edge <NUM> of implant <NUM>.

In some embodiments, the PEEK material surrounding the radiopaque marker may be enlarged in order to reinforce the surrounding structure. As also shown in <FIG>, peripheral frame <NUM> may have larger thickness proximate radiopaque marker <NUM> than adjacent to radiopaque marker <NUM>. For example, as shown in <FIG>, peripheral frame <NUM> may have a first thickness <NUM> proximate radiopaque marker <NUM> and a second thickness <NUM> adjacent to radiopaque marker <NUM>. As shown in <FIG>, this thicker area may be a rib <NUM>, such that first radiopaque marker <NUM> may be aligned with rib <NUM>. Rib <NUM> may extend in a superior-inferior direction (i.e., a substantially vertical direction) and may be disposed on a surface of the peripheral frame that faces radially inward toward a center of implant <NUM>. In some embodiments, rib <NUM> may extend the full height of implant <NUM>, from superior side <NUM> to inferior side <NUM>.

<FIG> is a schematic inferior view of implant <NUM>. As shown in <FIG>, implant <NUM> may include a second radiopaque marker <NUM> and a third radiopaque marker <NUM>. <FIG> is a schematic cross-sectional view of an implant taken as indicated in <FIG>. As shown in <FIG>, implant <NUM> may include a fourth radiopaque marker <NUM>.

As shown in <FIG>, first radiopaque marker <NUM> may be disposed proximate a superior surface (i.e., at superior side <NUM>) of implant <NUM> at first lateral side <NUM>. Second radiopaque marker <NUM> may be disposed proximate an inferior surface (i.e., at inferior side <NUM>) of implant <NUM> at first lateral side <NUM>. Third radiopaque marker <NUM> may be disposed proximate the inferior surface and at second lateral side <NUM>. Fourth radiopaque marker <NUM> may be diposed proximate the superior surface and at second lateral side <NUM>. Thus, as illustrated in <FIG>, the radiopaque markers are located at the four corners of the implant when viewed in the anterior-posterior direction. This may facilitate radiographic observation of the orientation and location of the implant when implanted.

In some embodiments, the radiopaque markers may be spherical, as shown in <FIG>. However, in other embodiments, the radiopaque markers may have any suitable shape.

The implant may include reinforced insertion tool engagement portions. <FIG> is a schematic enlarged view of a first tool engagement portion <NUM> (also referred to as simply first engagement portion) of implant <NUM>. (See also <FIG>. ) Implant may also include a second tool engagement portion (See <FIG>. ) As shown in <FIG>, first tool engagement portion <NUM> may extend from an outer surface of peripheral frame <NUM>. First engagement portion <NUM> may include a recess <NUM> configured to receive a gripping element of an insertion tool configured to hold the implant during an implantation procedure. In addition, first engagement portion <NUM> may include a protruding lip <NUM>. As shown in <FIG>, protruding lip <NUM> may have a thickness <NUM>. As also shown in <FIG>, recess <NUM> may have a depth <NUM>. In some embodiments, thickness <NUM> of protruding lip <NUM> and depth <NUM> of recess <NUM> of first engagement portion <NUM> may be substantially the same. With such a configuration, the amount of material removed from the housing to create the recess may be replaced in the protruding lip, thus maintaining substantially the same amount of material in the housing, and limiting any loss of structural integrity caused by hollowing out the recess to receive the insertion tool. The protruding lip also reinforces the gripping recess undercut to provide for a stronger connection with the insertion tool during extraction, if needed.

<FIG> is a schematic assembled view of opposing blades and a blade actuating component joined using T-shaped slots. <FIG> shows a similar view to that of <FIG>, but wherein the channels in the blade actuating component have a T-shaped cross-sectional shape. Specifically, <FIG> shows an inferior blade <NUM> and a superior blade <NUM>. As also shown in <FIG>, a blade actuating component <NUM> may be configured to deploy inferior blade <NUM> and superior blade <NUM>.

Superior blade <NUM> may include a first protruding portion <NUM> having a T-shaped cross-sectional shape. Inferior blade <NUM> may have a second protruding portion <NUM> having a T-shaped cross-sectional shape. First protruding portion <NUM> and second protruding portion <NUM> may be configured to be received by corresponding T-shaped channels in blade actuating component <NUM>. This T-shaped connection between the blades and the blade actuating component may provide more resistance to disengagement than the dovetail connection shown in <FIG>.

<FIG> is a schematic assembled view of opposing blades and a blade actuating component joined using rectangular-shaped slots. <FIG> shows a similar view to that of <FIG>, but wherein the channels in the blade actuating component have a rectangular cross-sectional shape. Specifically, <FIG> shows an inferior blade <NUM> and a superior blade <NUM>. As also shown in <FIG>, a blade actuating component <NUM> may be configured to deploy inferior blade <NUM> and superior blade <NUM>.

Superior blade <NUM> may include a first protruding portion <NUM> having a substantially rectangular cross-sectional shape. Inferior blade <NUM> may have a second protruding portion <NUM> having a substantially rectangular cross-sectional shape. First protruding portion <NUM> and second protruding portion <NUM> may be configured to be received by corresponding rectangular shaped channels in blade actuating component <NUM>. This rectangular-shaped connection between the blades and the blade actuating component may be easier to manufacture than the dovetail connection shown in <FIG> and the T-shaped connection shown in <FIG>.

Claim 1:
An implant (<NUM>), comprising:
a housing (<NUM>);
a blade (<NUM>), the blade (<NUM>) having a retracted position in the housing (<NUM>) and an extended position where the blade (<NUM>) extends outwardly from the housing (<NUM>); and
a blade actuating component (<NUM>), the blade actuating component (<NUM>) comprising a driven shaft portion (<NUM>) and a blade engaging portion (<NUM>);
wherein the blade actuating component (<NUM>) can move the blade (<NUM>) between the retracted position and the extended position;
the housing (<NUM>) including a first end (<NUM>), the first end (<NUM>) including a guide opening (<NUM>), the guide opening (<NUM>) comprising a hollow grooved portion (<NUM>) and a chamber portion (<NUM>), the hollow grooved portion (<NUM>) being connected to the chamber portion (<NUM>) and configured to receive a threaded fastener (<NUM>); and
the chamber portion (<NUM>) receiving a portion of the driven shaft portion (<NUM>) of the blade actuating component (<NUM>); and
the chamber portion (<NUM>) is configured to receive the driven shaft portion (<NUM>), wherein the cross-sectional shape of the chamber portion (<NUM>) in a plane transverse to the direction of travel of the blade actuating component (<NUM>) is configured to prevent rotation of the driven shaft portion (<NUM>).