Patent ID: 12245952

DETAILED DESCRIPTION

Posterior fixation constructs, comprised of implants including screws, rods, plates, rivets, nuts, bolts, set screws, connectors, etc., can be used to provide fixation for spinal anatomy during corrective techniques. Spine surgeons often perform spine surgery to relieve symptoms associated with degenerative disc disease, spinal deformity, scoliosis, or trauma, among other reasons. In spinal surgery, surgeons attempt to correct deformities, align vertebral bodies, and/or decompress the spinal cord and nerves.

Present posterior fixation device constructs are typically comprised of bone anchors (alternatively, polyaxial bone screws or pedicle screws), circular cross-section rods, and connectors. The variable position of the heads of the polyaxial screws allow for a range of special relationships between the rod and bone screws while still allowing connection between each other. There are several current issues with posterior fixation constructs including the inability to seat the rod within each of polyaxial screw bodies. In these instances, reduction techniques and instruments are used to forcibly deliver the rod the polyaxial head. As reduction force is delivered to the construct, the relationship between polyaxial screws and connected vertebral bodies becomes unpredictable. In some instances, the force delivered to the construct during surgery can cause problems, including bone screw dislodgment from the vertebral body (screw pullout) or implant fractures.

Typically, the surgeon must deliver anchors (e.g., pedicle screws, other bone screws, clips, etc.) to the vertebral bodies. Surgeons must determine a start-point, trajectory, and anchor length and anchor diameter intraoperatively. The surgeon exposes the bone in order to identify an appropriate anatomical start-point and trajectory for the pedicle screw. Using fluoroscopy, the surgeon delivers the anchor to the bone, taking care not to breach the pedicle or vertebral body. This technique exposes the patient, surgeon, and operating room staff to unnecessary radiation. In some instances, delivery of the pedicle screw results in a breach of the cortex and impingement of the nerves by the bone screw. Surgical planning (using radiographic images taken prior to surgery to determine the bone screw's start-point, trajectory, length, and shank diameter) can be used to reduce or eliminate intra-operative radiation associated with fluoroscopy. Prior to implantation the anatomy can be virtually corrected using planning software.

In deformity and degenerative surgeries, correction of malpositioned anatomy is desired. In some cases, only a partial correction is possible, but is worth achieving. In other cases, full correction is possible. One area of frustration for surgeons during delivery of a posterior fixation construct is bending the longitudinal elements (rods) and delivering and securing them to the fixation anchors (bone screws). In the present state, surgeons approximate the desired shape of the rod based on an estimate of the correction to be delivered to the patient. There is no tool or method to determine the optimal degree of correction required and the amount and degree of curvature or bends that need to be placed upon the rod. The rod bending and implantation often occurs at the end of the surgery, following the delivery of the bone screws and the associated receivers of the rod (screw head, etc.). Because this activity occurs at the end of the surgery, the surgeon may be fatigued, stressed, rushed, or otherwise operating with sub-optimal attention or energy. This critical portion of the procedure is what ultimately determines the relationship between vertebral bodies, the decompression of neural elements, and ultimate alignment of anatomy.

One objective of spine surgery is correction of a spinal deformity or re-alignment of vertebral bodies. Current practices require the surgeon to use intra-operative imaging and manipulation of implants that are fixed to the anatomy to adjust relationships between vertebral bodies to correct malalignment. The imaging tools available to the surgeon intraoperatively use radiation to assess relative position of the interested anatomy. It would be beneficial to have a tool and method to plan the surgery and determine (1) the position of implants within anatomy, (2) position of implants relative to other implants, and (3) position of vertebral bodies relative to other vertebral bodies.

These tools and methods disclosed allow the surgeon to perform a virtual surgery on a computer, tablet, smart phone, or other smart device. By planning the surgery prior to the operation, the surgeon can determine the proper three-dimensional alignment before the patient is surgically opened and/or in place on the operating room table. Pre-planning can eliminate some of the intraoperative decision making that takes valuable time while the patient is under sedation or anesthesia, and while the patient is exposed to infection in the operating room, for example with one or more open surgical incisions. Additionally, surgical planning tools and methods can help determine the proper implant selection, including but not limited to the style of implant, the model of implant, the material(s) of the implant, the quantities of implants, or the size parameters (length, width, depth, diameter, etc.) of the implant.

The systems and methods described herein may be utilized to correct other physiological ailments requiring patient-specific implants. For example, wedge-shaped implants for maintaining wedge osteotomies in the spine, or other orthopedic areas such as the hip, jaw, chin or knee for arthritic or non-arthritic conditions, may be designed with the teachings of the present disclosure. Particular procedures include: high tibial osteotomy (tibia), distal femoral osteotomy (femur), Evans wedge or Cotton wedge (foot and ankle).

FIG.1illustrates a posterior fixation construct10positioned within the lumbar spine. Polyaxial pedicle screws12are inserted into the vertebral body through pedicles. The start-point, trajectory, screw length, and diameter (e.g., shank diameter) are determined by the surgeon during surgery using fluoroscopic imaging. Longitudinal elements14(e.g., rods) are used to connect screws12in a particular relationship to each other, and thus, to maintain two or more vertebrae in a particular relationship to each other. Longitudinal element14may be rods, plates, or another type of geometry. In some constructs, connectors16, are used to provide stabilization or connect elements of the construct. The connector16may connect a rod to another rod, or a screw to another screw, or a rod to a screw, or a rod to a portion of bone, or other combinations.

FIG.2illustrates a common posterior fixation construct. Polyaxial pedicle screws12typically have several components. Bone screw shank22is used to connect the polyaxial screw12to the bony anatomy. Polyaxial screw body24is typically coupled to the shank22using a spherical mechanism the allows the shank22to articulate relative to body24. This allows body24to be positioned to receive rod14. The screw body24may then be tightened to a static relationship with the shank22. Set screw20is used to secure rod14into body24. The set screw20may also be used to fix the relationship between the screw body24and the screw shank22, or another element may accomplish this task.

FIG.3illustrates a plate type of posterior fixation construct30. This construct30uses bone screws34affixed to the vertebral bodies. Plate32is used to connect bone screws34and provide a mechanism to secure the relationship between bone screws34and the attached anatomy. Plate32has features38designed to secure plate32to screw34. Nut36is threaded about screw34and used to secure screw34to plate32.

FIG.4illustrates several components of a posterior fixation construct30. Screw34has two threaded portions, the bone screw thread shank42and machine screw thread proximal post41. Bone screw thread shank42is delivered to the vertebral body through the pedicle and provides fixation to the anatomy. Machine thread41provides a mechanism to deliver fastening nut36. Nut36secures plate32to bone screw34. Washers40can be used to provide spacing (angular, axial, etc.) between screw34, plate32, and nut36. Features38provide a recess for nut36to reside after delivering compression to plate32. When constructed, plate32sits on top of the shoulder43of bone screw34. Plate32has slots33that allow for machine threaded post41to pass though. Nut36is threaded on to post41to secure plate32to screw34by compressing plate32between nut36and shoulder43.

FIG.5illustrates a posterior fixation construct and associated anatomy when view on a radiograph. In this image, plates32and screws34are visible. Also shown are bone screw thread shank42and nut36.

FIG.6illustrates an embodiment of the present invention. Fixation plate50is comprised of longitudinal segments54and nodes52. Nodes52have features that provide for receiving of a fixation element or bone screw. Length, orientation, and shape of plate50, longitudinal segments54, and nodes52can be determined by using surgical planning software.

In one embodiment, the features are a hole53that allows for receiving of a bone screw. Holes53may be oriented orthogonal to a top or bottom surface. Alternatively, hole axis62may be oriented at an angle relative to a top or bottom surface (e.g., oriented at a non-orthogonal angle). Top surface61and/or bottom surface63may be curved or described by a radius60. Top surface61is shown inFIG.6to be concave and bottom surface63is shown as convex, but in other embodiments, bottom surface63may be concave and top surface61may be convex. In still other embodiments one or both of top surface61and bottom surface63may include one or more convex portion and one or more concave portion. Top and bottom surfaces61,63may be configured with features to provide improved locking between adjacent components (e.g., mating features including teeth, bumps, recesses). Top and bottom surfaces61,63may have a unique shape with features64that provide for accommodation of anatomical features. Top and bottom surfaces61,63may be angled relative to one another. Angle68, angle66, or arc70(FIG.6B), can be used to describe relationships between sections of top and bottom surfaces61,63. In some instances, node52can be positioned directly lateral to adjacent node52. Longitudinal segment54may be curved in three dimensions in order to locate node52in the optimal position over anatomical features.FIG.6Bshows a terminal node that could be located in an optimal location for an iliac bone anchor. The angle of the hole53, as shown inFIG.6B, can be angularly offset (e.g., non-parallel) from the primary plane67of plate50. Medial and lateral surfaces65shown inFIG.6Ccan be described as flat or contoured to fit anatomy or provide location for graft material. Surface65A is shown inFIG.6Cas flat, and surface65B is shown as contoured. Shape and topography of plate50, nodes52, holes53, and longitudinal element54can be determined using surgical planning and design software. The plate60may comprise multi-planar curves, twists, variable thicknesses, multiple sections of differing density, multiple sections of differing porosity, or multiple sections of differing flexibility/stiffness.

FIG.7illustrates another embodiment of fixation plate50. In one embodiment, node52can have features72to provide for seating against or around anatomy. When viewed in cross-section, longitudinal element74A,74B can have variable shapes to provide for mechanical performance or anatomical placement. Feature79comprising a concavity can be provided to allow for anatomical placement or mechanical performance. Surface81comprising a convexity can be provided to allow for anatomical placement or mechanical performance. Surface78can be textured to provide for anatomical placement or mechanical performance. In one embodiment, surface78can be roughened to provide for temporary fixation on the adjacent anatomy. Furthermore, surface78can be conditioned to encourage or discourage biological reactions. Surface78can be impregnated with biological agents to encourage bone growth and/or discourage bacterial growth. In one embodiment, cross-section76may be circular in shape. Thus, longitudinal elements74may either have similar cross-sectional profiles, or may have two or more different cross-sectional profiles.

FIG.8illustrates another embodiment of fixation plate50. Cross-section of nodes52are shown inFIGS.8A and8B. In one embodiment, nodes52contain holes53to provide for bone screws or another anatomical fixation element. Holes53may contain features88(e.g., teeth, grooves, bosses, keys, recesses, etc.) to allow for seating of a fastener and to provide secure relationship or lock between plate50, bone screw, and anatomy. Hole53can have a central axis62to provide communication between top and bottom surfaces. Nodes52may have top and bottom surfaces with features82to provide for anatomical placement or mechanical performance. Medial and lateral surfaces84,86can be configured to provide for anatomical placement or mechanical performance.

FIG.8Cshows another view of plate50and highlights the three-dimensionality of plate50. Lower arm55of plate50is shown to be out-of-plane relative to the upper section57. This out-of-plane nature can be applied in relation to the upper section57as a curvature representing or matching lordosis, kyphosis, or medial/lateral twisting in a target patient. In this embodiment, angles59,69and radii of curvature can be used to describe the relationship between holes53and surface of plate50. Nodes52may include different features, surfaces (e.g., medial vs. lateral, anterior vs. posterior), different hole locations and angulations, and multiple axes. Longitudinal segments54may vary in shape, length, or angulation. In some embodiments, portions of the plate50are not within the same plane as each other. In some embodiments, the plate50is asymmetric. In some embodiments, the asymmetry may be in relation to a longitudinal axis.

FIG.9illustrates another embodiment of plate50. Cross-sectional views inFIGS.9A,9B, and9Cshow that the size and density of longitudinal elements54can be varied. Mechanical performance, such as flexibility or stiffness, can be optimized by changing the shape and composition of longitudinal elements54. Furthermore, longitudinal elements can be manufactured with a porosity to provide optimized mechanical performance or biological response. Pores95can be sized to encourage biological response (e.g., adhesion) or to control/optimize flexibility, or even to increase durability or fatigue strength. The plate50may in alternative embodiments receive surface treatment to optimize biological response at the surface. First diameter90(FIG.9A) may be smaller than second diameter92or third diameter94. Feature91is configured for locking the plate50to a nut36or to a locking element113(FIG.10).

Additive manufacturing techniques such as laser sintering or electronic beam fusion can be used to build complex non-planar plates50with features to provide for anatomic seating or mechanical performance. Internal geometry particular to additive manufacturing, such as lattice, struts, or weaves may be used to create the preferred embodiment. Additive manufacturing techniques may include, but are not limited to: three-dimensional printing, stereolithography (SLA), selective laser melting (SLM), powder bed printing (PP), selective laser sintering (SLS), selective heat sintering (SHM), fused deposition modeling (FDM), direct metal laser sintering (DMLS), laminated object manufacturing (LOM), thermoplastic printing, direct material deposition (DMD), digital light processing (DLP), inkjet photo resin machining, and electron beam melting (EBM). Additive manufacturing techniques may be used in some embodiments to create a particular matrix of material/void patterns or a particular series of internal support structures of the material, thus controlling stiffness or flexibility, or the proclivity for the implant to bend in one direction more than another (e.g., more flexible along an X-Y plane than along an X-Z plane, etc.

FIG.10illustrates a plate50that has been placed in the lumbar spine. Construct110can be used to treat patients who have a degenerative or deformative condition of the spine. In one embodiment, plate50is fixed to the spine using bone screws100,102,104. Plate50can be designed to accommodate anatomy. Unique shapes or configurations of plate50can accommodate individual patient anatomy or mechanical performance. Plate50can additionally, or alternatively be configured to provide fixation to the sacrum and/or ilium. Sacral screw102and iliac screw100can provide fixation to areas outside of the spine. Surgeons using traditional fixation devices (rods, screws, connectors, etc.) recognize that bending a rod to the appropriate shape for iliac fixation is difficult and often results in the use of supplemental devices that are difficult to use.

Locking element113is configured to secure bone screw100,102,104to plate50. Longitudinal element54can be configured to (1) avoid anatomy (e.g., have a particular shape), (2) engage anatomy (e.g., grasp a particular landmark or feature, including a process or lamina), (3) have a desired mechanical performance (e.g., have particular dimensions or shape), or (4) provide a biological response (e.g., have a particular surface configuration or a particular coating). In one embodiment, locking element113can be configured to provide limited relative movement between bone screw100,102,104to encourage fusion or avoid causing or worsening adjacent segment disease (proximal junctional kyphosis). In one embodiment, locking element113acts to expand a spherical feature on the proximal end of bone anchor100,102,104. In one embodiment, locking element113and longitudinal element54can be configured to have mating features that constrict or control relative motion between components. Mating features can include teeth, grooves, bosses, reliefs, and surface finishes to allow for interdigitation and mechanical engagement between components.

FIG.11illustrates a bone anchor104and associated features. Proximal head110of bone anchor104can be spherical in shape to allow for variable angular position relative to plate50. Bone anchor shank112is configured to provide fixation to bony anatomy. In this embodiment, shank112is threaded and includes a cannulation116to facilitate implantation. In select spinal surgeries (percutaneous or minimally invasive), k-wires can be used to prepare a trajectory and depth for the bone anchor. The anchor104can be delivered over the wire to anatomy, with the wire extending through the cannulation116. Drive feature114is used to drive anchor104into bone and can be configured as hexagonal in shape, for interfacing with a mating hexagonal driving element (screwdriver, etc.).

Bone anchor104has a proximal head110that may have slits122to allow expansion (e.g., radial expansion) of proximal head110. As tapered plug123is delivered to head110, for example, by rotational threading, it causes expansion of head110. Internal threads118,120can be used to engage and retain plug123that is delivered to the head after final seating within plate50.

FIG.12illustrates a bone anchor104and plate50interface. Proximal head110can be spherical in nature and be configured to fit and be contained within pocket140of plate50. In one embodiment, pocket140can be spherical in nature.

FIG.13illustrates proximal features of a bone anchor104. Proximal head124can be configured to contain features that to allow expansion of head124into pocket140(FIG.12) to fix the relationship between bone anchor104and plate50. In one embodiment, cam126can be configured to expand head124upon rotation of cam126using drive feature132(e.g., driven by screwdriver, etc.). Profiled relief128can be configured to provide expansion of head124after final seating within plate50. In one embodiment, rotation of cam126causes contact between cam126and head124, and as cam126contacts profiled relief128, it causes expansion of the head124. Slits130interrupt the circumferential continuity of the head124and allow head124to expand (e.g., radially) and fix the relationship between anchor104and plate50.

FIG.14illustrates a bone anchor104and plate interface. Proximal head110and pocket140can contain several features to help secure anchor104to plate50. In one embodiment, threads41are present on the external surface of the proximal head110. As shown inFIG.14, head110, can be configured to have an arm146that can flex. Arm146extends proximally and radially simultaneously, and thus is swept-back angularly in relation to a longitudinal axis of the anchor104. When inserting anchor104through plate50and into bone, the arm146can flex inwardly to allow it to pass shoulder144. The arm146is shown inFIG.14in a position after it has passed the shoulder144. Once past the shoulder144, the arm146can be used to brace anchor against plate50. The arm146is shown inFIG.14applying a normal force against an inner surface103of the shoulder144. The arm146extends past the bottom surface142of the plate50, to the shank112. In other embodiments, the arm146may remain between the two opposing surfaces of the plate50. Proximal head threads41can be used to secure anchor104and plate50(e.g., by screwing a nut, or screwing the locking element150ofFIG.15, over the threads41such that it contacts the shoulder144at an outer surface105of the shoulder, opposite the inner surface103). In one embodiment, the anchor104is driven through plate50and proximal head110into pocket140through plate50. Locking element150(FIG.15) can be configured to be threaded onto tread41to lock anchor104to plate50.

FIG.15illustrates proximal features of a bone anchor104, plate50, and locking element features. Shown inFIG.15is plate50, longitudinal element54, proximal head110(of bone anchor104) containing drive feature154. Proximal drive feature154can be configured as hexagonal in shape and is used (with a driver) to drive anchor104through plate50and into bony anatomy. In one embodiment, locking element150can be threaded and configured to lock plate50between anchor104and locking element150. Features152on locking element150can be used to drive locking element150into plate50to secure anchor104to plate50.

Plate50, anchor100,102,104, and locking element150and features thereof can be manufactured of materials typical of medical implants, including, but not limited to, titanium, titanium alloy, Ti6Al4V, stainless steel, cobalt chrome, polymers, polyether ether ketone (PEEK), etc. Anchors100,102,104may alternatively be constructed of rivets, bolts, or other fasteners.

FIG.16illustrates a method200for utilizing a system for producing patient-specific implants. In step202three-dimensional scan data of a patient is obtained from a CT, MRI, x-ray, PET or another type of imaging modality. Step204segments the scan data into relevant and irrelevant sets. In one embodiment, relevant data set includes bony tissue. Segmentation step204can use a thresholding operation, automated filters, machine learning, or artificial intelligence to identify bony tissue based on tissue density and pixel density. The relevant data is then converted into three-dimensional volume and models in step206. In some cases, the relevant data may correspond to a diseased or deformed portion of the spine, including a particular number of successive vertebrae and the surrounding soft tissue. In some cases, the entire spine may be selected.

A computer may be used for processing and manipulation of this data. For example, the user interface associated with least one computer memory that is not a transitory signal and comprises instructions executable by at least one processor may be utilized to select a region of interest. A system containing the memory may include any number of custom stand-alone devices, or any mobile device, such as an iPhone, smart phone, ipad, tablet, laptop, desktop, or mainframe computer. The system may also be configured to access the memory remotely, for example, via internet browser access or other wireless means. The three-dimensional image can be converted into a form such that is can be manipulated by a user to measure anatomical deformities related to the disease (e.g., spine disease). The information can then be used by a medical professional or technical professional in conjunction or collaboration with a medical professional, to design (reconfigure) the optimized geometry of the corrected spine, thus allowing the design of an implant to treat the particular disease or malady.

In step208the computer memory is utilized to apply one or more predictive correction guidelines to the spine or to the selected portion of the spine, or at least a section thereof. A number of predictive correction guidelines may be utilized, but in one embodiment a set of three predictive guidelines are applied, relating to pelvic tilt, sagittal alignment, and lumbar lordosis. The predictive guideline regarding pelvic tilt is can be the equation wherein the pelvic tilt less than 20 degrees. The predictive guideline regarding sagittal vertebral axis (SVA) can be defined by the equation wherein the C7 sagittal vertical axis is not more than 5 cm from the most posterior portion of the superior sacral endplate. The predictive guideline regarding lumbar lordosis114is defined by the equation wherein an absolute value of the difference between pelvic incidence and lumbar lordosis less than 10 degrees. Predictive guidelines may be used as described in “Current Surgical Strategies to Restore Proper Sagittal Alignment” by Luiz Pimenta, Journal of Spine, 2015, Volume 4, Number 4, (2 pages), which is incorporated herein by reference in its entirety for all purposes.

In decision point210, the computer memory is utilized to determine whether, in the current state of the spine provided by the three-dimensional image, the predictive guidelines from step208are achieved. If one or more of the predictive guidelines from step208are not true for the spine segments selected, then a user may utilize a user interface to adjust the virtual anatomy into a preferred alignment, as shown in step212. For example, if the pelvic tilt is determined to be 20° or greater, a user may input or toggle an adjustment that changes the amount of correction in order to achieve a pelvic tilt less than 20°. If it is determined that the predictive guidelines are all achieved (whether user adjustment was or was not required), the system generates three-dimensional implant(s) geometry in step214. The three-dimensional implant(s) geometry may in some cases define a single interbody device, several interbody devices, or posterior fixation plate50geometry (including node52, hole53, and longitudinal element54geometries). In some cases, the three-dimensional geometry may define one or more interbody devices for a single level of the spine, or in other cases may define one or more interbody devices from two or more levels of the spine. In one embodiment, the data creates a point cloud map, which is then converted to multiple interconnected triangles to create a surface mesh. Based on known density discrepancies between bone and tissue, the three-dimensional mesh surface is parsed for bone surface data and converted to a three-dimensional volume. The converted data is saved into memory with a readable file format, such as .STL, .OBJ, or other CAD (computer-aided design) readable file format. In this CAD readable file format, the individual spine vertebral bodies can be isolated and manipulated in the axial, coronal, and sagittal planes.

After the three-dimensional geometry is generated, the system checks in decision point216whether the particular correction is within cleared parameters. For example, within a particular amount of correction that is approved under a regulatory clearance; or, within a particular amount of correction that is approved under an IRB-controlled or FDA-controlled clinical trial. Additional to, or instead of, the amount of correction, other parameters may determine whether the three-dimensional geometry performs within cleared parameters in decision point216. For example, the thickness of longitudinal element54or node52may be controlled and many not fall below a threshold or the dimensions and density of an interbody device may not exceed a predetermined value. If the correction (or other parameters) is not within the cleared range(s), user-initiated input may be performed, as in step212. In some embodiments, the system may suggest the amount to adjust each parameter of spine alignment, allowing the user to accept this suggestion, or to choose a different value of change. In some cases, step212may not be necessary, for example, when certain procedures do not have implant-based regulatory limitations. A particular manner of validating a cleared amount of correction, is to check the three-dimensional envelope of the spine implant at both the maximum material condition and the least material condition. For example, an FDA clearance may take into account both of these conditions, in one or more patient indications.

Once the three-dimensional geometry is accepted by the user, and, if applicable, by the limitations of step216, the implant(s) may be manufactured. The patient prescription containing volumes of implant(s) may comprise one or more three-dimensional files that are used in additive manufacturing, including, but not limited to: .AMF, .X3D, Collada (Collaborative Design Activity), .STL, .STP, .STEP, or .OBJ. The patient prescription may alternatively comprise one or more three dimensional files, including, but not limited to: .IGS, .STP, .STEP, .3ds, .blend, .dae, .ipt, ,skp, .fbx, .lwo, .off, .ply, .sldprt, .sldasm, and .X_T. In some cases, the patient prescription may also include one or more two-dimensional files, for example, to map or guide the surgical treatment, or to stage the utilization of each implant. The two-dimensional files may include, but are not limited to: .dwg, .dwf, .dxf, .pdf, or .acis.

The step218may include using the three-dimensional files to manufacture the implant(s) using one or more additive manufacturing or subtractive (traditional) manufacturing methods. Additive manufacturing methods include, but are not limited to: three-dimensional printing, stereolithography (SLA), selective laser melting (SLM), powder bed printing (PP), selective laser sintering (SLS), selective heat sintering (SHM), fused deposition modeling (FDM), direct metal laser sintering (DMLS), laminated object manufacturing (LOM), thermoplastic printing, direct material deposition (DMD), digital light processing (DLP), inkjet photo resin machining, and electron beam melting (EBM). Subtractive (traditional) manufacturing methods include, but are not limited to: CNC machining, EDM (electrical discharge machining), grinding, laser cutting, water jet machining, and manual machining (milling, lathe/turning). The additive (or subtractive) manufacturing may be used to construct the plate50, or the anchors100,102,104, or the locking elements150.

Following the manufacture of the implant, a bone-friendly scaffold is created for fusion to one or more vertebrae. The implant may comprise one or more of the following materials: titanium, titanium alloy, titanium-6AL-4V, tantalum, and PEEK (polyether ether ketone). The implant may also comprise/be coated with a biologic material. Examples of potential biological materials may include, but are not limited to, hydroxylapetite (hydroxyapetite), recombinant human bone morphogenic proteins (rhBMP-2, rhBMP-7), bioactive glass, beta tri-calcium phosphate, human allograft (cortical and/or cancellous bone), xenograft, other allograft, platelet rich plasma (PRP), stem cells, and other biomaterials. In addition, synthetic ceramics having osteogenic properties may be utilized.

The manufacture of the implant may be further guided by patient information, including patient age, patient weight, BMI, activity level, DEXA score, bone density, or prior patient surgical history. For example, a patient with a high BMI (body mass index) can require a stiffer or stronger implant. The lattice structure forming the implant can be optimized to meet the patient's biomechanical needs for stability. Additionally, a patient with a low BMI and/or with osteoporotic bone or osteopenia (low DEXA score) can benefit from an implant having lower stiffness, thus helping to reduce the risk of poor performance. Furthermore, a patient having a previously failed fusion may be at risk for adjacent level disc disease and/or proximal joint kyphosis. An implant can be tailored to alleviate this particular situation.

The implant is packaged and sterilized in step220. The implant is shipped in sterile form to the surgical site (operating room of a hospital or surgery center) in step222. In some embodiments, step220may be performed at the site of surgery, thus making step222unnecessary. The implant is implanted within a patient in step224.

The method200may be used to simulate and construct any portion or characteristic of the plate50, including node locations, hole locations, hole angles, longitudinal segment shape, longitudinal segment thickness, or longitudinal segment density. The method200may utilize any of the steps and techniques disclosed in co-pending U.S. patent application Ser. No. 16/207,116, filed on Dec. 1, 2018, and entitled “Systems and Methods for Multi-Planar Orthopedic Alignment,” which is incorporated by reference in its entirety for all purposes.

The ranges disclosed herein also encompass any and all overlap, sub-ranges, and combinations thereof. Language such as “up to,” “at least,” “greater than,” “less than,” “between,” and the like includes the number recited. Numbers preceded by a term such as “approximately,” “about,” and “substantially” as used herein include the recited numbers (e.g., about 10%=10%), and also represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount.

While embodiments have been shown and described, various modifications may be made without departing from the scope of the inventive concepts disclosed herein.