111 may range from about 100 microns to about 500 microns, about 100 microns to about 150 microns, about 100 microns to about 150 microns, about 150 microns to about 200 microns, about 200 microns to about 250 microns, about 250 microns to about 300 microns, about 300 microns to about 350 microns, about 350 microns to about 400 microns, about 400 microns to about 450 microns, about 450 microns to about 500 microns, or between any two aforementioned values.

In some embodiments, endplate volume 121 serves as the primary interface that promotes boney ingrowth. In some embodiments, porosity of endplate volume 121 may be achieved by lattice structure similar that found in structural volume 111 or may be a perforated solid material such as but not limited to stainless steel alloys, titanium alloys, or cobalt-chrome alloys. In some embodiments, average pore size of endplate volume 121 may range from about 100 microns to about 500 microns, about 100 microns to about 150 microns, about 100 microns to about 150 microns, about 150 microns to about 200 microns, about 200 microns to about 250 microns, about 250 microns to about 300 microns, about 300 microns to about 350 microns, about 350 microns to about 400 microns, about 400 microns to about 450 microns, about 450 microns to about 500 microns, or between any two aforementioned values.

In some embodiments, as better seen in FIGS. 2 and 3, solid frame 102 may be configured to encompass, or encapsulate structural volume 111. In some embodiments, as seen in FIGS. 1 and 3, solid frame 102 may partially enclose the anterior portion or side BA, posterior portion or side BP, two side portions, and upper and lower endplate volume (AL and AU, respectively), i.e., endplate volume 121 of implant 100. In some embodiments, solid frame 102 may be monolithic structure or may be a connection of various modular components, e.g., a frame enclosing the perimeter of upper and lower endplate volumes 121, a first solid plate positioned at anterior side (BA) of structural volume 111 (i.e., solid body portion 101), a second solid plate positioned at posterior side (BP) of structural volume 111.

Many embodiments are principally directed to 3D printing technologies and other additive manufacturing processes. However, in some embodiments, subtractive manufacturing processes may also be applied to portions and sub-features of the disclosed implants. Various embodiments and components may be manufactured by a subtractive manufacturing process including, but not limited to, machining (e.g., machining tools, such as saws, lathes, milling, machines, drill presses, electrical discharge machining (EDM)) is used to physically remove material to achieve the desired geometry and dimensions of the lattices and pores structures. In some embodiments, surface treatment steps may be applied to provide porous structures on the implant.

In some embodiments, solid body portion 101 may comprise a threaded hole 103 configured to provide an attachment mechanism for an insertion instrument. In some embodiments threaded hole 103 may be configured to receive bone graft material that may be injected through threaded hole 103 and into a hollow, interior cavity or graft chamber 130 of cervical corpectomy implant 100. In some embodiments, threaded hole 103 may be circular and have a diameter from about 2 mm to about 6 mm, about 2 mm to about 4 mm, about 4 mm to about 6 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, or between any two aforementioned values. In some embodiments, implant 100 may comprise engagement slot 108 for an attachment of insertion instrument for installation of implant 100 to patient.

In the illustrated embodiment, graft chamber 130 extends lengthwise along longitudinal axis A1 providing a lengthwise cavity through implant 100. In some embodiments, interior cavity or graft chamber 130 may be configured to allow for bone graft material to be packed within the device. In some embodiments, solid body portion 101 may comprise one or more graft hole(s) 105 configured to accept osteogenic material, bone graft, or other bone growth and healing substances to facilitate bone growth and/or improve radiolucency of the device. In some embodiments, graft hole 105 may generally comprise circular, oval, or polygonal shape openings, including, for example, generally triangular, diamond, square, rectangular, or hexagonal shapes. In some embodiments, when graft hole 105 is circular or oval, graft hole 105 may have a diameter (or the longest distance between two points outer perimeter graft hole 105 is non-circular) of about 5 mm to about 15 mm, about 5 mm to about 7 mm, about 7 mm to about 9 mm, about 9 mm to about 11 mm, about 11 mm to about 13 mm, about 13 mm to about 15 mm, or between any two aforementioned values

As seen in FIGS. 1-3, in some embodiments, cervical corpectomy implant 100 may comprise a sloped or chamfered edge 107 at the edge intersection of anterior volume and upper endplate volume 121 and edge intersection of anterior volume lower endplate. In some embodiments, chamfered edge 107 provide a sloped surface for one or more cervical plate bone screws 140 to be placed adjacent to the device and allow stabilizing cervical plate 150 to be placed adjacent to the implant. Chamfered edge may provide enough clearance such that bone screw 140 does not come in contact with cervical corpectomy implant 100 or a. In some embodiments, chamfered edge 107 may be inclined at an angle α (as seen in FIG. 3), measured between upper plane α1 of implant 100 and bone screw trajectory α2. In some embodiments, angle α may range from about 15° to about 60°, about 20° to about 55°, about 25° to about 50°, about 30° to about 45°, about 35° to about 40°, about 15° to about 20°, about 20° to about 25°, about 25° to about 30°, about 30° to about 35°, about 35° to about 40°, about 40° to about 45°, about 45° to about 50°, about 50° to about 55°, about 55° to about 30°, or between any two aforementioned values, based on the position of the bone screw trajectory α2.

In some embodiments, cervical corpectomy implant 100 may comprise structural volume 111 comprising more open lattice structures configured to reduce the stiffness and radio-opacity of the implant. In some embodiments, structural volume 111 may comprise a plurality of lateral holes 113 configured for facilitating fusion between the graft chamber and adjacent bone for bone graft packing and/or to further improve radiolucency. In some embodiments, implant 100 may comprise from 1 to 5 lateral hole(s) 113 depending on the length of implant 100.

Referring now to FIGS. 4-8, various perspectives of a cervical corpectomy implant 100 showing lattice structures in structural volume 111 are shown. In various embodiments, the cervical corpectomy implant disclosed in FIGS. 4-8 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant in FIGS. 1-3.

FIGS. 4 and 5 show anterior volume 161 and posterior volume 162 of structural volume 111. FIGS. 6 and 7 show perspective views of side volumes 163 of structural volume 111. As seen in FIGS. 4-7, structural volume 111 may comprise stochastic, or random, lattice structures 160 filling the volume space of structural volume 111. As used herein, the term “lattice” refers to a repeating, grid-like pattern or matrix of interconnected elements within a 3D object that fill a volume or conform to a surface. Interconnected elements may include but are not limited to beams, surfaces, or plates interconnected to form a 3D framework. Lattice structures described in this document may be an ordered structure like a honeycomb or exhibit partial or full random, stochastic structures.

In some embodiments, lattice structures 160 may comprise a periodic or repeating lattice structure of one or more shapes including but not limited to squares, rectangles, diamonds, or other higher-dimension polygonal structures such as pentagons, hexagons, or octagons. In some embodiments, any part (e.g., anterior volume, e.g., 161; posterior volume, e.g., 162; side volume, e.g., 163; or endplate volume, e.g., 121) of structural volume 111 comprising the lattice structure 160 may each have a volume fill from about 50% to about 99%, about 50% to about 95%, about 55% to about 90%, about 60% to about 85%, about 65% to about 80% about 70% to about 75%, about 50% to about 55%, about 55% to about 60%, about 60% to about 65%, about 65% to about 70%, about 70% to about 75%, about 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, about 95% to about 99%, or between any two aforementioned values, of the volume space of structural volume 111 (or anterior volume, e.g., 161; posterior volume, e.g., 162; side volume, e.g., 163; or endplate volume, e.g., 121). As used herein, “average volume fill percentage,” “volume fill percentage,” or “volume fill %” refers to the percentage of lattice that occupies the void space within the total volume of the structure. For instance, 50% volume fill percentage in a side wall volume indicates that half of the volume is occupied by the lattice and 50% is empty or open space.

In some embodiments, anterior volume 161, posterior volume 162, and two side volumes 163 may comprise the same volume fill %. In some embodiments, upper endplate volume and lower endplate volume may comprise the same volume fill %. In some embodiments, upper endplate volume and the lower endplate volume each may comprise lower volume fill % compared to anterior volume 161, posterior volume 162, and two side volumes 163, and the second side volume.

As used herein, the term “porosity” refers to the percentage of volume space in a that is occupied by pores, void spaces, or openings within the lattice structure. In some embodiments, porosity refers to the areas where the solid material is absent that made within the total volume of the structure. In some embodiments, pores may vary in size, shape, and distribution, impacting the overall structure or stochasticity of the lattice.

In some embodiments, any component (any one of anterior volume, e.g., 161; posterior volume, e.g., 162; side volume, e.g., 163; or endplate volume, e.g., 121) of structural volume 111 comprising the lattice structure 160 may have a porosity from about 30% to about 70%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, about 45% to about 50%, about 50% to about 55%, about 55% to about 60%, about 60% to about 65%, about 65% to about 70%, about 30% to about 65%, about 35% to about 60%, about 40% to about 55%, about 45% to about 55%, or between any two aforementioned values, of the volume space of structural volume 111 (independently anterior volume, e.g., 161; posterior volume, e.g., 162; side volume, e.g., 163; or endplate volume, e.g., 121).

In some embodiments, any one or more of structural volume 111 component (anterior volume, posterior volume, side volume, or endplate volume) may the same the same porosity or different porosity. In some embodiments, the upper endplate volume and the lower endplate volume may comprise greater porosity compared to anterior volume 161, posterior volume 162, and two side volumes 163. In some embodiments, anterior volume 161 and posterior volume 162 may have lower porosity compared to two side volumes 163. This configuration allows anterior volume 161 and posterior volume 162 to have a tighter lattice structure that does not allow bone to grow to the outside of device.

As used herein, the term “lattice density” refers to the degree of “tightness” of lattice structure in a given structural volume or the distribution of volume fill % throughout a given structural volume. For example, an exemplary side volume having an average of 80% volume fill, (80% of volume space is occupied by lattice structure) may have a uniform lattice density, i.e., degree of tightness is uniform throughout the volume. In this configuration the any given subsection or a portion of the structural volume will comprise the same or similar volume fill %. In another example, a structural volume having a lattice density gradient will have different volume fill % at different parts throughout the volume space. For example, a side volume (e.g., 163) having an overall or average volume fill of 80% may have higher volume fill %, i.e., 90% fill throughout the first half of the volume space in a given direction within the volume space, and have lower fill %, i.e., 70% fill throughout the remaining half of the volume space providing an average of 80% volume fill.

In some embodiments, lattice density may be uniform in a plane or cross-section along longitudinal axis A1 (see FIG. 1). In other words, given any planar cross-section of structural volume 111 along longitudinal axis A1, there is no gradient in lattice density from the bottom of the cross-section to the top of the cross-section. In some embodiments, lattice density may be uniform in a plane or cross-section along latitudinal axis B1 (see FIG. 1). In other words, given any planar cross-section of structural volume 111 along longitudinal axis B1, there is no gradient in lattice density between two side walls.

In some embodiments, lattice density may have a gradient or density in a plane or cross-section along longitudinal axis A1 (see FIG. 1). For instance, given any planar cross-section of structural volume 111 along longitudinal axis A1, the lattice density may increase, decrease, or fluctuate extending from the bottom of the cross-section to the top of the cross-section. Likewise, in some embodiments, lattice density may be uniform in a plane or cross-section along latitudinal axis B1 (see FIG. 1). For instance, given any planar cross-section of structural volume 111 along latitudinal axis B1, the lattice density may increase, decrease, or fluctuate extending between two side walls of implant 100.

The capability for any given structural volume to have varying lattice fill %, porosity, stochasticity, and lattice density allows for the disclosed corpectomy device to be tailored to fit into specific surgical areas where certain portions of the corpectomy implant may need to be stiffer to provide structural rigidity to a certain portion of the implant (by having higher lattice density and/or porosity), or may need to be less stiff to provide sufficient porosity for boney growth outside or around the device to be achieved (by having lower lattice density), all while providing an overall structural stability of the implant and maintaining higher radiolucency compared to solid metal implants.

Now referring to FIG. 8, a top-down perspective view of cervical corpectomy implant 100 is shown. As seen in FIG. 8, cervical corpectomy implant 100 may include endplate volume 121 that comprises endplate lattice 165 that includes a different lattice density as compared to the density of anterior volume 161, posterior volume 162, and side volume 163 of structural volume 111. In some embodiments, endplate lattice 165 may fill from about 50% to about 99%, about 50% to about 95%, about 55% to about 90%, about 60% to about 85%, about 65% to about 80% about 70% to about 75%, about 50% to about 55%, about 55% to about 60%, about 60% to about 65%, about 65% to about 70%, about 70% to about 75%, about 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, about 95% to about 99%, or between any two aforementioned values, of the volume space of endplate volume 121.

In some embodiments, endplate volume 121 may comprise a perforated solid material having a porosity that promotes bone ingrowth In some embodiments, average pore size of endplate volume 121 may range from about 100 microns to about 500 microns, about 100 microns to about 150 microns, about 100 microns to about 150 microns, about 150 microns to about 200 microns, about 200 microns to about 250 microns, about 250 microns to about 300 microns, about 300 microns to about 350 microns, about 350 microns to about 400 microns, about 400 microns to about 450 microns, about 450 microns to about 500 microns, or between any two aforementioned values.

In some embodiments, endplate volume 121 may comprise a plurality of anti-migration features such as teeth 123 that engage with the bottom (or top) surface of the superior (or inferior) vertebrae to prevent migration of cervical corpectomy implant 100 from an installed state. In some embodiments, cervical corpectomy implant 100 may comprise 3 to 8, or 3, 4, 5, 6, 7, or 8 anti-migration feature, e.g., teeth 123. In some embodiments as seen in FIG. 9, implant may be inserted into space between vertebra along C1 direction such that shallow angle incline 125 of teeth 123 facilitates the insertion of the implant and steep angle incline 127 reduces/prevents retropulsion, or migration after the implant is inserted.

In some embodiments, the shallow angle incline 125 (angle β) may range from about 5° to about 40°, about 10° to about 35°, about 15° to about 20°, or about 5°, about 10°, about 15°, about 20°, about 25°, about 30°, about 35°, about 40°, or between any two aforementioned values. In some embodiments, steep angle incline 127 (angle δ) may range from about 50° to about 85°, about 55° to about 80°, about 60° to about 75°, about 65° to about 70°, or about 50°, about 55°, about 60°, about 65°, about 70°, about 75°, about 80°, about 85°, or between any two aforementioned values.

Now referring to FIG. 10, a perspective view of a second example of a cervical corpectomy implant 200, is disclosed. In various embodiments, the cervical corpectomy implant 200 as disclosed in FIG. 10 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant 100 in FIGS. 1-8. In various embodiments, cervical corpectomy implant 200 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant 100. For example, cervical corpectomy implant 200 may include, but is not limited to, features such as solid body portion 201, chamfered edge 207, engagement slot 208, structural volume 211, endplate volume 221, threaded hole 203 may be and graft chamber 230 comprising the same, similar and/or substantially the same features. In some embodiments, cervical corpectomy implant 200 may comprise one or more lateral holes 213 on side of structural volume 211 similar to as seen in cervical corpectomy implant 100. In some embodiments, cervical corpectomy implant 200 may comprise one or more graft holes (not shown) on the anterior side of solid body portion 201 that are configured to accept osteogenic material, bone graft, or other bone growth and healing substances to facilitate bone growth and/or improve radiolucency of the device. In some embodiments, cervical corpectomy implant 200 may not include a solid frame (e.g., solid frame 102) that encompasses, or encapsulates structural volume 211, Instead, as seen in FIGS. 10 and 11, cervical corpectomy implant 200 may comprise anterior volume 261 and posterior volume 262. Compared to solid frame 102, anterior volume 261 and posterior volume 262 may provide additional reduction in stiffness improving flexibility, and improve radiolucency.

As seen further in FIG. 10, cervical corpectomy implant 200 may comprise anti-migration features on endplate volume 221, e.g., conical spike(s) 223, to prevent migration of cervical corpectomy implant 200 from an installed state. In some embodiments, cervical corpectomy implant 200 may comprise 3 to 8, or 3, 4, 5, 6, 7, or 8 anti-migration feature 123 In some embodiments, any anti-migration feature disclosed in the present disclosure may be used with any cervical corpectomy implant disclosed in this document.

As seen in FIG. 11, in some embodiments, lattice density or degree of randomness (stochastic property) may be different between anterior volume 261, posterior volume 262, and side volume 263 to control or modulate bone ingrowth/graft packing to certain directions. In some embodiments, anterior volume 261 and posterior volume 262 may have a tight lattice structure that does not allow bone to grow to the outside of the device along the anterior and the posterior directions. In some embodiments, lattice structures of anterior volume 261 and posterior volume 262 may independently fill from about 70% to about 99%, about 70% to about 75%, about 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, about 95% to about 99%, or between any two aforementioned values, of the volume space of anterior volume 261 and posterior volume 262.

In some embodiments, average pore size of anterior volume 261 and posterior volume 262 may independently range from about 100 microns to about 500 microns, about 100 microns to about 150 microns, about 100 microns to about 150 microns, about 150 microns to about 200 microns, about 200 microns to about 250 microns, about 250 microns to about 300 microns, about 300 microns to about 350 microns, about 350 microns to about 400 microns, about 400 microns to about 450 microns, about 450 microns to about 500 microns, or between any two aforementioned values. In some embodiments, porosity of anterior volume 261 and posterior volume 262 may independently range from about 70% to about 99%, about 70% to about 75%, about 75% to about 80%, about 80% to about 85%, about 85% to about 90%, about 90% to about 95%, about 95% to about 99%, or between any two aforementioned values, of the volume space of anterior volume 261 and posterior volume 262.

Now referring to FIG. 12, a perspective view of a third example of a cervical corpectomy implant 300, is disclosed. In various embodiments, cervical corpectomy implant 300 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant 100 or 200 such as threaded hole 303 that may be configured to provide an attachment mechanism for an insertion instrument. As seen in FIG. 12, cervical corpectomy implant 300 may comprise one or more grooves 305 that is configured to provide clearance for cervical bone screw trajectory 307. Such grooves 305 may be indents or relief areas such that the cervical bone screw does not make contact with grooves 305. In other embodiments, such indents or relief areas of grooves 305 may make contact with the cervical bone screw. As seen in FIG. 12 and the exploded view in FIG. 13, cervical corpectomy implant 300 may comprise outer shell 309 enclosing the interior implant lattice. In some embodiments, cervical corpectomy implant 300 may comprise sagittal window frame 311 to provide bone ingrowth and injection of bone graft materials. In some embodiments, sagittal window frame 311 may comprise circular shape openings and/or various polygonal shape openings, including, for example, triangular, diamond, square, rectangular, or hexagonal shapes. In some embodiments, the interior of cervical corpectomy implant 300 may comprise core lattice 313 which is configured to provide bone ingrowth and reduce stiffness and radiolucency. In some embodiments, cervical corpectomy implant 300 may comprise end cap lattice 315 comprises different lattice density and/or stochastic properties compared to core lattice 313. In some embodiments, outer shell 309 may be fabricated from materials such as stainless steel alloys, commercially pure titanium, titanium alloys, Grade 5 titanium, super-elastic titanium alloys, cobalt-chrome alloys, superelastic metallic alloys (e.g., Nitinol, super elasto-plastic metals, such as GUM METAL®), ceramics and composites thereof such as calcium phosphate (e.g., SKELITE™), thermoplastics such as polyaryletherketone (PAEK) including polyetheretherketone (PEEK), polyetherketoneketone (PEKK) and polyetherketone (PEK), carbon-PEEK composites, PEEK-BaSO₄polymeric rubbers, polyethylene terephthalate (PET), fabric, silicone, polyurethane, silicone-polyurethane copolymers, polymeric rubbers, polyolefin rubbers, hydrogels, semi-rigid and rigid materials, elastomers, rubbers, thermoplastic elastomers, thermoset elastomers, elastomeric composites, rigid polymers including polyphenylene, polyamide, polyimide, polyetherimide, polyethylene, epoxy, bone material including autograft, allograft, xenograft or transgenic cortical and/or corticocancellous bone, and tissue growth or differentiation factors, partially resorbable materials, such as, for example, composites of metals and calcium-based ceramics, composites of PEEK and calcium based ceramics, composites of cPEEK with resorbable polymers, totally resorbable materials, such as, for example, calcium based ceramics such as calcium phosphate, tri-calcium phosphate (TCP), hydroxyapatite (HA)-TCP, calcium sulfate, or other resorbable polymers such as polyketide, polyglycolide, polytyrosine carbonate, polycaprolactone, polylactic acid or polylactide and their combinations.

Now referring to FIGS. 14A and 14B, a side view and a top-down perspective view of cervical corpectomy implant 300 are shown. As stated above, cervical corpectomy implant 300 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant 100 or 200 for example, anti-migration feature 323 (corresponding to anti-migration features 123 and 223). In some embodiments, cervical corpectomy implant 300 may comprise interior lattice structure 325 which is configured to effectively reduce the device stiffness and improve radiolucency (x-ray effectiveness) by reducing the density of the material, as compared to solid material which requires the entire space volume to be filled with materials. In some embodiments, cervical corpectomy implant 300 may comprise an undercut along plane D1 that provides extra clearance for the spinal cord such that cervical corpectomy implant 300 may be installed conforming with the curvature of the spinal cord.

Now referring to FIGS. 15A-15C, a front perspective view, a rear perspective view, and a top-down perspective view of a cervical corpectomy implant 400 are shown. In various embodiments, cervical corpectomy implant 400 may have the same, similar and/or substantially the same features and functionality as explained above with respect to cervical corpectomy implant 100, 200, or 300 such as threaded hole 403 that may be configured to provide an attachment mechanism for an insertion instrument. In some embodiments, cervical corpectomy implant 400 may comprise outer shell 409 enclosing the interior implant lattice. In some embodiments, cervical corpectomy implant 400 may comprise sagittal window frame 411 to provide bone ingrowth and injection of bone graft materials. In some embodiments, cervical corpectomy implant 400 may comprise anti-migration feature(s) 423 that reduces/prevents retropulsion, or migration after the implant is inserted. In some embodiments, cervical corpectomy implant 400 may comprise further interior lattice structure 425 configured to effectively reduce the device stiffness and improve radiolucency (x-ray effectiveness). In some embodiments, cervical corpectomy implant 400 may comprise bone screw 417 that is inserted through the corpectomy implant to engage the vertebral endplates.

In FIGS. 16A and 16B, interior lattice structure 525 of an embodiment of cervical corpectomy implant 500 is shown. In some embodiments, cervical corpectomy implant 500 may be the same, as similar to, or substantially the same as cervical corpectomy implants 100, 200, 300 or 400. As seen in FIGS. 16A and 16B, interior lattice structure 525 may comprise an open cell lattice in a periodic, repeating structure rather than a stochastic or random lattice. In this configuration, bone growth and bone graft packing may be more uniform and evenly distributed in the periodic structure, and the interior of cervical corpectomy implant is easier to clean.

In some embodiments, any one of implants 100, 200, or 300 as disclosed in FIGS. 1-16B of may be modified to be an interbody implant, for example, for use in the disc space in the cervical spine, by reducing the height to be able to fit between the disc space. Such interbody implant would comprise the same, similar and/or substantially the same features as any one of implants as disclosed in FIGS. 1-16B. In some embodiments, any one of implants 100, 200, or 300 may be modified along various planes, e.g., X-Y, Y-Z, or X-Z, to accommodate various cavity size of adjacent boney structures between vertebrae in a patient's spine. In some embodiments, any one of implants 100, 200, or 300