SYSTEMS AND METHODS FOR THE INCREMENTAL BENDING OF BONE FIXATION PLATES
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 63/481,834, filed on January 27, 2023, and entitled "FRAMEWORK AND METHODS FOR THE INCREMENTAL BENDING OF BONE FIXATION PLATES," the disclosure of which is hereby incorporated by reference in its entirety.
GOVERNMENT SUPPORT CLAUSE
[0002] This invention was made with government support under sponsor award 2133630 awarded by the National Science Foundation. The government has certain rights in the invention.
BACKGROUND
[0003] Often to heal significant fractures, bone removal for tumors, or other trauma, fixation plates are bent to a patient's anatomy and affixed to the bone with multiple screws. The clinical success depends to a large degree to the ability of the surgeon to match the shape of the plate to the existing bone. Often 3-dimensional models of the patient's bone structure exists from a CT scan or other imaging, but sometimes it does not. When a numerical 3-D model exists, a plate can be printed via additive manufacturing or additive manufacturing may be used to create a model that the surgeon or other technicians may use to bend a plates prior to surgery. Sometimes surgeons must bend the plates to a patient's bone structure while they are in the operating room. An example of craniofacial fractures held together by fixation plates 101 (e.g., the plates 101A, 101B, 101C, and 101D) is shown FIG. 1.
[0004] The simplest, and most common of the fixation plates 101 is shown in the included FIG. 2. They are typically made from a titanium alloy or stainless steel and have reduced cross section in some areas to facilitate bending. These plates 101 are bent to a patient's anatomy using the tool 105. Major causes of failure include excessive gaps between the plate 101 and bone, damage to the metal due to repeated reversed bending to approach fit and poor states of residual stress due to bending.
[0005] While the truly ideal solution would include solid-modeling of the patient's osteo- mechanics to provide proper stiffness and strength and ideally place screws and change the local stiffness of the plate 101, the clinical standard of care uses standard plates of varied length with a standard distance between screw insertion points. These are bent by standard tools 105, an example of which is shown in FIG. 2. Note other tools 105 are also used to curve or twist the plate.
SUMMARY
[0006] A method for the incremental bending of bone fixation plates is provided. The method includes: receiving a mathematical curve describing a desired attachment line between a bone fixation plate and the bone of a patient; receiving the linear bone fixation plate comprising a plurality of screw holes; for each screw hole of the plurality of screw holes: fixing the hole to a rigid fixture that holds the screw hold in place; and bending the fixation plate until a vector difference between the hole and a next screw hole is achieved based on the curve and the location of the screw hole and the next screw hole on the curve.
[0007] The method described above can improve the standard of care method in the following ways: 1). This can be carried out using digital data from, for example, CT Scan or other patient imaging. No need to fit the fixation plate to a patient or solid model; 2). This method can offload many hours of work from a surgeon. Several plates may be needed for a single incident; 3) This can provide much improved accuracy of fit to a patient. This reduces failures and improves outcomes; 4). This can reduce overbending or reversed bending, reducing damage to the plate; 5). If the bending sequence is controlled, the residual stress state in the plate can be controlled, improving fatigue performance; and 6). Just the right amount of over or under-bend can be used to provide appropriate forces for healing.
[0008] In some aspects, the techniques described herein relate to a method for the incremental bending of bone fixation plates including: receiving medical imaging data for a bone surface of a patient to be repaired by a computing device; based on the medical imaging data, generating a curve representing the bone surface to be repaired by the computing device; receiving a linear bone fixation plate including a plurality of screw holes by the computing device; and for each screw hole of the plurality of screw holes: attaching the linear bone fixation plate to a rigid fixture at the screw hole; calculating an amount of bend to apply to the linear fixation plate based on a desired vector difference between a location of the screw hole on the curve and a location of the next screw hole of the plurality of screw holes on the curve; and bending the linear fixation plate according to the calculated bend while the linear bone fixation plate remains attached to the ridged fixture at the screw hole.
[0009] In some aspects, the techniques described herein relate to a method, wherein the bone fixation plate includes a Y-junction.
[0010] In some aspects, the techniques described herein relate to a method, wherein generating the curve includes including drawing a continuous path in virtual space describing the bone surface of the patient and generating the curve based on the path. [0011] In some aspects, the techniques described herein relate to a method, wherein the virtual space is generated based on the medical imaging data.
[0012] In some aspects, the techniques described herein relate to a method, wherein the linear fixation plate is bent by a robot.
[0013] In some aspects, the techniques described herein relate to a method, further including performing surgery on the patient to attach the linear fixation plate to the bone surface.
[0014] In some aspects, the techniques described herein relate to a method, wherein the linear fixation plate is not further bent or modified during the surgery.
[0015] In some aspects, the techniques described herein relate to a system for the incremental bending of bone fixation plates including: one or more processors; and a computer-readable medium with computer-executable instructions stored thereon that when executed by the one or more processors cause the one or more processors to: receive medical imaging data for a bone surface of a patient to be repaired; based on the medical imaging data, generate a curve representing the bone surface to be repaired; receive a linear bone fixation plate including a plurality of screw holes; and for each screw hole of the plurality of screw holes: attach the linear bone fixation plate to a rigid fixture at the screw hole; calculate an amount of bend to apply to the linear fixation plate based on a desired vector difference between a location of the screw hole on the curve and a location of the next screw hole of the plurality of screw holes on the curve; and bend the linear fixation plate according to the calculated bend while the linear bone fixation plate remains attached to the ridged fixture at the screw hole.
[0016] In some aspects, the techniques described herein relate to a system, wherein the bone fixation plate includes a Y-junction. [0017] In some aspects, the techniques described herein relate to a system, wherein generating the curve includes including drawing a continuous path in virtual space describing the bone surface of the patient and generating the curve based on the path. [0018] In some aspects, the techniques described herein relate to a system, wherein the virtual space is generated based on the medical imaging data.
[0019] In some aspects, the techniques described herein relate to a system, wherein the linear fixation plate is bent by a robot.
[0020] In some aspects, the techniques described herein relate to a system, further including performing surgery on the patient to attach the linear fixation plate to the bone surface.
[0021] In some aspects, the techniques described herein relate to a system, wherein the linear fixation plate is not further bent or modified during the surgery.
[0022] In some aspects, the techniques described herein relate to a computer-readable medium with computer-executable instructions stored thereon that when executed by one or more processors cause the one or more processors to: receive medical imaging data for a bone surface of a patient to be repaired; based on the medical imaging data, generate a curve representing the bone surface to be repaired; receive a linear bone fixation plate including a plurality of screw holes; and for each screw hole of the plurality of screw holes: attach the linear bone fixation plate to a rigid fixture at the screw hole; calculate an amount of bend to apply to the linear fixation plate based on a desired vector difference between a location of the screw hole on the curve and a location of the next screw hole of the plurality of screw holes on the curve; and bend the linear fixation plate according to the calculated bend while the linear bone fixation plate remains attached to the ridged fixture at the screw hole. [0023] In some aspects, the techniques described herein relate to a computer-readable medium, wherein the bone fixation plate includes a Y-junction.
[0024] In some aspects, the techniques described herein relate to a computer-readable medium, wherein generating the curve includes including drawing a continuous path in virtual space describing the bone surface of the patient and generating the curve based on the path.
[0025] In some aspects, the techniques described herein relate to a computer-readable medium, wherein the virtual space is generated based on the medical imaging data.
[0026] In some aspects, the techniques described herein relate to a computer-readable medium, wherein the linear fixation plate is bent by a robot.
[0027] In some aspects, the techniques described herein relate to a computer-readable medium, further including performing surgery on the patient to attach the linear fixation plate to the bone surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying figures, which are incorporated herein and form part of the specification, illustrate a malware detection system and method. Together with the description, the figures further serve to explain the principles of the malware detection system and method described herein and thereby enable a person skilled in the pertinent art to make and use the malware detection system and method.
[0009] FIG. 1 is an illustration of example bone fixation plates;
[0010] FIG. 2 is an illustration of example bone fixation plates;
[0011] FIG. 3 is an illustration of an example system for the Incremental bending of bone fixation plates; [0012] FIG. 4 is an illustration of an example bone fixation plate showing a coordinate system;
[0013] FIG. 5 is an illustration of an example method for the Incremental bending of bone fixation plates; and
[0014] FIG. 6 shows an exemplary computing environment in which example embodiments and aspects may be implemented.
DETAILED DESCRIPTION
[0015] In the following description, specific details are set forth describing some embodiments consistent with the present disclosure. Numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that some embodiments may be practiced without some or all of these specific details. The specific embodiments disclosed herein are meant to be illustrative but not limiting. One skilled in the art may realize other elements that, although not specifically described here, are within the scope and the spirit of this disclosure. In addition, to avoid unnecessary repetition, one or more features shown and described in association with one embodiment may be incorporated into other embodiments unless specifically described otherwise or if the one or more features would make an embodiment non-functional. In some instances, well known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.
[0016] FIG. 3 is an illustration of an incremental system 300 for the Incremental bending of bone fixation plates. As shown the system 300 includes several components including a curve generator 305, a bend engine 310, and a rigid fixture 320. Other components may include a robot 340. Each of the components of the system 300 may be implemented together or separately using one or more general purpose computing device such as the computing device 600 illustrated with respect to FIG. 6.
[0017] The curve generator 305 may receive medical imaging data 303 for a bone surface of patient. The medical imaging data 303 may be digital data and may include, but is not limited to, MRI data, cat scan data, and X-Ray data. Other types of medical imaging data 303 may be included.
[0018] The curve generator 305 may generate a curve 306 that represents the bone surface of the patient that is to be repaired using a fixation plate 101. In some embodiments, the curve generator 305 may generate the curve 306 by first generating a virtual space from the medical imaging data 303. The virtual space may represent the bone or bone surface of the patient. The curve generator 305 may then generate a path in the virtual space that runs along the bone surface. The curve generator 305 may then generate the curve 306 based on the path. The curve is determined by the path along the fixation plate. It is usually a representation of a plane through the solid model of the patient bone. The desired normals for the holes lie in the plane of intersection normal to the model of the patient bone.
[0019] The bend engine 310 may generate a series of bends to apply to the fixation plate 101 such that it conforms to the curve 306 and bone surface that will be applied to.
Because the fixation plate 101 is bent prior to the beginning of surgery, and not during the surgery as it is applied to the bone surface, the amount of time spent by the doctor manipulating and bending the fixation plate 101 is greatly reduced. Reducing the time spent in surgery saves time and money for the healthcare system and increases safety and medical outcomes for the patient. [0020] The overall goal of plate bending is having the plate fit the patient's anatomy with minimal gaps. That said, current standard of care only attempts to control the plate shape by bending at each of the screw holes in the plate and moving to the next. For a best possible match, a surgeon would draw a continuous path (curved line) along the bone in real or virtual space and there would be a number of points where the screws would intersect the line. These are nominally spaced equally with the pitch of the screw holes in the plate. A perfect plate 101 would have one hole at each intersection point and the normal vector to the bone at this location would be coincident with the normal vector to the perimeter of the hole, located at the center of the hole.
[0021] Assume there are n holes in the plate 101. In some embodiments, cartesian coordinate system may be defined based on the first hole of the fixation plate 101, where X is the direction down the undeformed plate, Z is upward away from the patient and Y is in the plate direction, described by the right-hand rule. Such a plate 101 is illustrated in FIG. 4. Other coordinate systems may be used.
[0022] The linear plate 101 can be described by the location of each of the centers of each of the n holes and the normal to each of them. The shape of the deformed or bent plate 101 is also adequately described the locations of the n holes and their normals, all of which can be described in this cartesian frame. The distance between holes, even after bending will be very similar to the pitch from one hole to another. With this constraint on hole-to-hole distance, the shape of the deformed plate can be defined as the vector normal directions from the center of each hole at a given Z axis location.
[0023] The bend engine 310 may calculate a shape for the fixation plate 101 that conforms the fixation plate 101 to the curve 306. In some embodiments, this shape can be created by for each hole of the fixation plate 101, fixing hole / to a rigid fixture 320 that holds its center in place and then firmly gripping hole i+1 and bending so that the right vector difference is obtained between holes / an i+1. This vector difference may be calculated by the bend engine 310 with reference to the fixation plate 101 and the curve 306. This process can be done in an iterative manner to correct for spring back. Next, the hole i+1 is fixed to the rigid fixture 320 and the right vector is provided for hole i+2 by the bend engine 310. This process may continue for n-1 holes. After this process, the whole shape of the bent or deformed fixation plate 101 may be slightly corrected for possible errors in the hole pitch by further bending.
[0024] There are many ways to carry out this algorithm. One way is fixing one hole, gripping the next hole with pliers and bending around the X, Y and Z axes to give the right normal for each pair of holes. The normal may be provided by the bend engine 310 based on the curve 306. This can be done by a multi-purpose robot 340, or a simple 3-degree of freedom system. It simply has to have enough moment that can be applied to get bends and a positional or rotational feedback system to give the final vectors of each n holes. This method can be extended to other plate topologies, with Y-junctions, bends and so forth.
[0025] FIG. 5 is an illustration of a method 500 for the Incremental bending of bone fixation plates. The method 500 may be implemented by the system 300 including the robot 340.
[0026] At 510, medical image data for a bone surface is received. The medical imaging data 303 may be received by the curve generator 305. The medical imaging data 303 may include X-rays, cat scans, MRI scans and other types of medical images. The medical imaging data 303 may be of a broken bone of a patient, for example.
[0027] At 520, a curve is generated from the medical imaging data 303. The curve 306 may be generated by the curve generator 305. In some embodiments, the curve generator 305 may generate the curve 306 by generating a virtual environment representing the bone of the patient from the medical imaging data 303. The curve generator 305 may then generate a path on the bone surface in the virtual environment. The path may be used to generate the curve 306.
[0028] At 530, a linear bone fixation plate is received. The plate 101 may be received by the robot 340. The plate 101 may have a plurality of screw holes arranged in an order.
[0029] At 540, the bone fixation plate is attached to a rigid fixture at the screw hole. The bone fixation plate 101 may be attached to rigid fixture 320 at the screw hole by the robot 340. Depending on the embodiment, the rigid fixture may be part of the robot 340. The rigid fixture 320 may hold the plate 101 at the selected screw hole so that the plate 101 may be bent in the x, y, and z directions by the robot 340. The screw hole may be the screw hole that has not yet be considered by the bend engine 310.
[0030] At 550, a bend is calculated for the next screw hole of the fixation plate. The bend may be calculated by the bend engine 310. In some embodiments, the bend may be such that the next screw hole (and the attached screw hole) and both normal to the calculated curve 306. In some embodiments, the bend engine 310 may calculate a vector difference between the location of the next screw hole on the curve 306 and the location of the attached screw hole on the curve 306.
[0031] At 560, the plate is bent according to the calculated bend. The fixation plate 101 may be bent by the robot 340.
[0032] At 570, whether there are any remaining screws in the plate is determined. If there are no remaining screw holes, then the method 500 may continue at 580. Else, a next screw hole is selected and the method 500 may return to 540 when the plate 101 will continue to be bent. [0033] At 580, surgery is performed on the patient using the bent fixation plate. The surgery may be performed by one or more doctors. Because the plate 101 was bent before the surgery began, the doctor should not have to make any more adjustments to the fixation plate 101 before attaching to the portion of the bone surface modeled using the curve 306.
[0015] FIG. 6 shows an exemplary computing environment in which example embodiments and aspects may be implemented. The computing device environment is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality.
[0016] Numerous other general purpose or special purpose computing devices environments or configurations may be used. Examples of well-known computing devices, environments, and/or configurations that may be suitable for use include, but are not limited to, personal computers, server computers, handheld or laptop devices, multiprocessor systems, microprocessor-based systems, network personal computers (PCs), minicomputers, mainframe computers, embedded systems, distributed computing environments that include any of the above systems or devices, and the like.
[0017] Computer-executable instructions, such as program modules, being executed by a computer may be used. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Distributed computing environments may be used where tasks are performed by remote processing devices that are linked through a communications network or other data transmission medium. In a distributed computing environment, program modules and other data may be located in both local and remote computer storage media including memory storage devices. [0018] With reference to FIG. 6, an exemplary system for implementing aspects described herein includes a computing device, such as computing device 600. In its most basic configuration, computing device 600 typically includes at least one processing unit 602 and memory 604. Depending on the exact configuration and type of computing device, memory 604 may be volatile (such as random access memory (RAM)), non-volatile (such as read-only memory (ROM), flash memory, etc.), or some combination of the two. This most basic configuration is illustrated in FIG. 6 by dashed line 606.
[0019] Computing device 600 may have additional features/functionality. For example, computing device 600 may include additional storage (removable and/or nonremovable) including, but not limited to, magnetic or optical disks or tape. Such additional storage is illustrated in FIG. 6 by removable storage 608 and non-removable storage 610.
[0020] Computing device 600 typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by the device 600 and includes both volatile and non-volatile media, removable and nonremovable media.
[0021] Computer storage media include volatile and non-volatile, and removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Memory 604, removable storage 608, and non-removable storage 610 are all examples of computer storage media. Computer storage media include, but are not limited to, RAM, ROM, electrically erasable program read-only memory (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computing device 600. Any such computer storage media may be part of computing device 600.
[0022] Computing device 600 may contain communication connection(s) 612 that allow the device to communicate with other devices. Computing device 600 may also have input device(s) 614 such as a keyboard, mouse, pen, voice input device, touch input device, etc. Output device(s) 616 such as a display, speakers, printer, etc. may also be included. All these devices are well known in the art and need not be discussed at length here.
[0023] It should be understood that the various techniques described herein may be implemented in connection with hardware components or software components or, where appropriate, with a combination of both. Illustrative types of hardware components that can be used include Field-programmable Gate Arrays (FPGAs), Application-specific Integrated Circuits (ASICs), Application-specific Standard Products (ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), etc. The methods and apparatus of the presently disclosed subject matter, or certain aspects or portions thereof, may take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, or any other machine-readable storage medium where, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for practicing the presently disclosed subject matter.
[0024] Although exemplary implementations may refer to utilizing aspects of the presently disclosed subject matter in the context of one or more stand-alone computer systems, the subject matter is not so limited, but rather may be implemented in connection with any computing environment, such as a network or distributed computing environment. Still further, aspects of the presently disclosed subject matter may be implemented in or across a plurality of processing chips or devices, and storage may similarly be affected across a plurality of devices. Such devices might include personal computers, network servers, and handheld devices, for example.
[0025] Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.