Clamp tool attachment type alignment marker for orthopedic procedures

Abstract

An exemplary system includes a clamping tool having an opposable surface configured to rest on and bear against a bone surface; and a mixed reality surgical system alignment marker attached to the clamping tool.

Description

[Technical field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 212,008, filed June 17, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to bone tracking during orthopedic surgical procedures. [Background technology]

[0003] Surgical joint repair procedures include repair and / or replacement of damaged or diseased joints. In many cases, surgical joint repair procedures, such as, for example, joint arthroplasty, involve replacing the damaged joint with a prosthesis that is implanted into the patient's bone. Properly selecting a prosthesis of appropriate size and shape and properly positioning the prosthesis to ensure optimal surgical results can be challenging. To aid in alignment, surgical procedures often include preparing the damaged bone surface and using surgical instruments to control cutting or drilling of the bone to accept the prosthesis.

[0004] Virtual visualization tools allow surgeons to use three-dimensional modeling of bone geometry to facilitate pre-operative planning of joint repair and replacement. These tools can assist surgeons in designing and / or selecting surgical guides and implants that closely match the patient's anatomy, improving surgical outcomes by customizing the surgical plan for each patient. Summary of the Invention

[0005] This disclosure describes various techniques for intraoperative surgical guidance using mixed reality (MR)-based visualization for surgical joint repair procedures. These techniques may be used independently or in various combinations to support specific stages or settings of a surgical joint repair procedure or to provide a multifaceted ecosystem that supports a surgical joint repair procedure. As described below, the alignment markers may be attached to a clamping tool, which may be attached to a patient's bone (e.g., the coracoid process of the scapula). Examples of clamping tools include, but are not limited to, a scissor-type device having two sections (e.g., a hemostat) that pivot about a pin. The clamping tool may include a surface configured to rest on and bear against a bone surface (e.g., the upper region of the glenoid cavity, etc.) to resist rotation or other movement. The clamping tool may include a component configured to lock the clamping tool in place, such as a ratchet locking mechanism. The alignment markers may provide a reference for a transformation matrix used to align virtual objects (e.g., a virtual image of the glenoid cavity, etc.) to their corresponding physical objects. By attaching the alignment marker to the bone using a clamping tool, the alignment marker can be more firmly attached to the bone, and thus the techniques of the present disclosure may improve the accuracy of surgical steps that are guided based on the position of the alignment marker.

[0006] The details of various embodiments of the disclosure are set forth in the accompanying drawings and the description below. Various features, objects, and advantages will become apparent from the description, the drawings, and the claims. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram of an orthopaedic surgical system according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a block diagram of an orthopaedic surgical system including a mixed reality (MR) system, according to one embodiment of the present disclosure. [Diagram 3]1 is a flow chart illustrating exemplary stages of a surgical life cycle. [Figure 4] 1 is a schematic diagram of a visualization device for use in a mixed reality (MR) system, according to an embodiment of the present disclosure. [Diagram 5] FIG. 1 is a block diagram illustrating example components of a visualization device for use in a mixed reality (MR) system, according to an example of the present disclosure. [Figure 6] 1 is a flow chart illustrating exemplary steps of the pre-operative phase of a surgical life cycle. [Figure 7] 1 is a flow chart showing exemplary steps in a shoulder repair surgery. [Figure 8] 1 illustrates an exemplary technique for aligning a three-dimensional virtual bone model to a patient's real bone structure observed during joint repair surgery. [Figure 9] 1 illustrates an exemplary system including an alignment marker attached to a clamping tool, according to one or more aspects of the present disclosure. [Figure 10] 1 illustrates an exemplary system including an alignment marker attached to a clamping tool, according to one or more aspects of the present disclosure. [Figure 11] 1 illustrates an example of a clamping tool according to one or more aspects of the present disclosure. [Figure 12] 1 illustrates an example of a clamping tool according to one or more aspects of the present disclosure. [Figure 13] 1 illustrates another example of a clamping tool, according to one or more aspects of the present disclosure. [Figure 14] 1 illustrates another example of a clamping tool, according to one or more aspects of the present disclosure. [Figure 15] 1 illustrates another example of a clamping tool, according to one or more aspects of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present disclosure relates to a clamping tool that attaches alignment markers to a patient's bone (e.g., scapula, etc.) to provide a reference for a transformation matrix used in a mixed reality system. The clamping tool comprises an opposable surface configured to rest on and bear against a bone surface (e.g., coracoid process of the scapula, etc.). The alignment marker may comprise a polyhedron having a pattern recognizable by a computer vision system (e.g., QR code, barcode, image, etc.) on one or more faces to facilitate alignment of the patient's orientation with the orientation of the image(s) overlaid via the mixed reality system.

[0009] The registration markers may be used in conjunction with a mixed reality (MR) visualization system to aid in the creation, execution, verification, and / or modification of a surgical plan before and during a surgical procedure. Because MR, or in some cases VR, may be used to interact with the surgical plan, the surgical plan may be referred to in this disclosure as a "virtual" surgical plan. Visualization tools other than or in addition to a mixed reality visualization system may be used in accordance with the techniques of this disclosure. For example, a surgical plan created by the BLUEPRINT™ system available from Wright Medical Group, NV, or another surgical planning platform, may include information defining various surgical procedure characteristics, such as characteristics of specific surgical procedure steps to be performed by a surgeon on a patient in accordance with a surgical plan that includes, for example, bone or tissue preparation steps and / or steps for the selection, modification, and / or placement of implant components. Such information may include, in various embodiments, the dimensions, shape, angles, surface contours, and / or orientation of the implant components selected or modified by the surgeon, the dimensions, shape, angles, surface contours, and / or orientations defined in the bone or tissue by the surgeon in a bone or tissue preparation step, and / or the locations, axes, planes, angles, and / or entry points that define the placement of the implant components by the surgeon relative to the patient's bone or tissue. Information such as the dimensions, shapes, angles, surface contours, and / or orientations of the patient's anatomical features may be obtained from imaging (e.g., x-ray, CT, MRI, ultrasound or other images), direct observation, or other techniques. In some embodiments, ... implant components may be determined by the surgeon in a method for determining the location of the implant components in the bone or tissue of the patient.

[0010] In this disclosure, the term "mixed reality" (MR) refers to the display of virtual objects such that a user sees an image that includes both real physical objects and virtual objects. Virtual objects may include text, two-dimensional surfaces, three-dimensional models, or other elements perceivable by a user that do not actually exist in the physical real-world environment in which they coexist. Additionally, virtual objects described in various embodiments of the present disclosure may include, for example, graphics, images, animations, or videos presented as 3D or 2D virtual objects. Virtual objects may also be referred to as virtual elements. Such virtual elements may or may not be analogues of real-world objects. In some embodiments, in mixed reality, a camera may capture an image of the real world and modify the image to present a virtual object within the context of the real world. In such embodiments, the modified image may be displayed on a screen that is head-mounted, handheld, or otherwise viewable by the user. In some embodiments, in mixed reality, a see-through (e.g., transparent) holographic lens, sometimes referred to as a waveguide, may enable a user to see real-world objects, i.e., real objects in a real-world environment, e.g., real anatomical structures, through the holographic lens, and simultaneously see virtual objects.

[0011] The Microsoft HOLOLENS™ headset, available from Microsoft Corporation, Redmond, Washington, is an example of an MR device with see-through holographic lenses, sometimes referred to as waveguides, that allow a user to simultaneously see real-world objects through the lenses and projected 3D holographic objects. The Microsoft HOLOLENS™ headset, or similar waveguide-based visualization devices, are examples of MR visualization devices that may be used in accordance with some embodiments of the present disclosure. Some holographic lenses may display holographic objects with some degree of transparency through the see-through holographic lenses, such that a user sees real-world objects and virtual holographic objects. In some embodiments, some holographic lenses may sometimes completely prevent a user from seeing real-world objects, instead allowing the user to see the virtual environment completely. The term mixed reality may also include scenarios in which one or more users can perceive one or more virtual objects generated by a holographic projection. In other words, "mixed reality" may include cases in which a holographic projector generates holograms of elements that appear to the user as being present in the user's actual physical environment.

[0012] In some examples, in mixed reality, the location of some or all of a presented virtual object is relative to the location of a physical object in the real world. For example, a virtual object may be tied to a table in the real world such that the virtual object is visible when the user looks in the direction of the table, but is not visible when the table is not in the user's field of view. In some examples, in mixed reality, the location of some or all of a presented virtual object is not relative to the location of a physical object in the real world. For example, a virtual item may always appear in the top right of the user's field of view, regardless of where the user is looking.

[0013] Augmented reality (AR) is similar to MR in that it is a presentation of both the real world and virtual elements, although AR generally refers to a presentation that is mostly real with some virtual additions added to "augment" the real world presentation. For purposes of this disclosure, MR is considered to include AR. For example, in AR, portions of a user's physical environment that are in shadow may be selectively illuminated without illuminating other areas of the user's physical environment. This embodiment is also an example of MR in that the selectively illuminated areas are considered virtual objects superimposed on the portions of the user's physical environment that are in shadow.

[0014] Further, in this disclosure, the term "virtual reality" (VR) refers to an immersive artificial environment experienced by a user through sensory stimuli (such as sight and sound) provided by a computer. Thus, in virtual reality, the user may not be able to see any physical objects that exist in the real world. Video games set in fantasy worlds are a common example of VR. The term "VR" also includes scenarios in which a user is presented with a completely artificial environment in which the positions of some virtual objects are based on the positions of corresponding physical objects relative to the user. A walk-through VR attraction is an example of this type of VR.

[0015] The term "extended reality" (XR) is a term that encompasses a variety of user experiences, including virtual reality, mixed reality, augmented reality, and other user experiences that involve the presentation of at least some perceivable elements as present in the user's environment (not present in the user's real-world environment). Thus, the term "extended reality" may be considered a species of MR and VR. XR visualizations may be presented with any of the techniques for presenting mixed reality described elsewhere in this disclosure, or may be presented using techniques for presenting VR, such as VR goggles.

[0016] Visualization tools are available that utilize patient image data to generate three-dimensional models of bone contours to facilitate preoperative planning of joint repair and replacement. These tools enable surgeons to design and / or select surgical guides and implant components that closely match the patient's anatomy. These tools can improve surgical outcomes by customizing surgical plans for each patient. One example of such a visualization tool for shoulder repair is the BLUEPRINT™ system available from Wright Medical Group, NV. The BLUEPRINT™ system provides the surgeon with a two-dimensional plan view of the bone repair area and a three-dimensional virtual model of the repair area. The surgeon can use the BLUEPRINT™ system to select, design, or modify the appropriate implant components, determine how to optimally position and orient the implant components as well as the shape of the bone surfaces that will receive the components, and design, select, or modify the surgical guide tool(s) or instruments to execute the surgical plan. The information generated by the BLUEPRINT™ system is compiled into a pre-operative surgical plan for the patient and stored in a database in an appropriate location (e.g., a server on a wide area network, local area network, or global network) that is accessible to the surgeon or other healthcare providers before and during the actual surgery.

[0017] FIG. 1 is a block diagram of an orthopaedic surgical system 100 according to an embodiment of the present disclosure. The orthopaedic surgical system 100 includes a set of subsystems. In the embodiment of FIG. 1, the subsystems include a virtual planning system 102, a planning support system 104, a manufacturing and delivery system 106, an intraoperative guidance system 108, a medical education system 110, a monitoring system 112, a predictive analytics system 114, and a communication network 116. In other embodiments, the orthopaedic surgical system 100 may include more, fewer, or different subsystems. For example, the orthopaedic surgical system 100 may omit the medical education system 110, the monitoring system 112, the predictive analytics system 114, and / or other subsystems. In some embodiments, the orthopaedic surgical system 100 may be used for surgical tracking, in which case the orthopaedic surgical system 100 may be referred to as a surgical tracking system. In other cases, the orthopaedic surgical system 100 may be generally referred to as a medical device system.

[0018] A user of the orthopaedic surgical system 100 may use the virtual planning system 102 to plan an orthopaedic surgical procedure. A user of the orthopaedic surgical system 100 may use the planning support system 104 to review a surgical plan created using the orthopaedic surgical system 100. A manufacturing and delivery system 106 may assist in the manufacturing and delivery of items necessary to perform an orthopaedic surgical procedure. An intra-operative guidance system 108 provides guidance to assist a user of the orthopaedic surgical system 100 in performing an orthopaedic surgical procedure. A medical education system 110 may assist in the education of users, such as medical professionals, patients, and other types of individuals. A pre-operative and post-operative monitoring system 112 may assist in monitoring a patient before and after the patient undergoes surgery. A predictive analytics system 114 may assist medical professionals with various types of predictions. For example, the predictive analytics system 114 may apply artificial intelligence techniques to, for example, determine a classification, e.g., diagnosis, of an orthopedic joint condition, determine what type of surgery a patient should undergo and / or what type of implant to use for the procedure, and determine the types of items that may be required during surgery.

[0019] The subsystems of the orthopaedic surgical system 100 (i.e., virtual planning system 102, planning support system 104, manufacturing and delivery system 106, intraoperative guidance system 108, medical education system 110, pre-operative and post-operative monitoring system 112, and predictive analytics system 114) may include various systems. The systems in the subsystems of the orthopaedic surgical system 100 may include various types of computer systems, computing devices, including server computers, personal computers, tablet computers, smartphones, display devices, Internet of Things (IoT) devices, visualization devices (e.g., mixed reality (MR) visualization devices, virtual reality (VR) visualization devices, holographic projectors, or other devices for presenting extended reality (XR) visualization), surgical tools, and the like. In some examples, a holographic projector may project holograms for general viewing by multiple users or a single user without a headset, rather than only by a user wearing a headset. For example, the virtual planning system 102 may comprise an MR visualization device and one or more server devices, the planning support system 104 may comprise one or more personal computers and one or more server devices, etc. A computer system is a set of one or more computer systems configured to operate as a system. In some embodiments, one or more devices may be shared between two or more subsystems of the orthopaedic surgical system 100. For example, in the previous embodiment, the virtual planning system 102 and the planning support system 104 may comprise the same server device.

[0020] 1, devices included in the subsystems of the orthopaedic surgical system 100 may communicate using a communications network 116. The communications network 116 may comprise various types of communications networks, including one or more wide area networks, such as the Internet, a local area network, etc. In some embodiments, the communications network 116 may comprise wired and / or wireless communication links.

[0021] Many variations of the orthopaedic surgical system 100 are possible in accordance with the techniques of the present disclosure. Such variations may include more or fewer subsystems than the version of the orthopaedic surgical system 100 shown in FIG. 1. For example, FIG. 2 is a block diagram of an orthopaedic surgical system 200 including one or more mixed reality (MR) systems, according to an example of the present disclosure. The orthopaedic surgical system 200 may be used to create, verify, update, modify, and / or implement a surgical plan. In some examples, the surgical plan may be created pre-operatively, such as by using a virtual surgical planning system (e.g., the BLUEPRINT™ system), and then verified, modified, updated, and displayed during surgery, for example, using MR visualization of the surgical plan. In other examples, the orthopaedic surgical system 200 may be used to create a surgical plan immediately prior to or during surgery, as needed. In some examples, the orthopaedic surgical system 200 may be used for surgical tracking, in which case the orthopaedic surgical system 200 may also be referred to as a surgical tracking system. In other cases, the orthopaedic surgical system 200 may be referred to generally as a medical device system.

[0022] In the example of Figure 2, the orthopaedic surgical system 200 includes a pre-operative surgical planning system 202, a medical facility 204 (e.g., a surgery center or hospital), a storage system 206, and a network 208 (which allows users of the medical facility 204 to access stored patient information, such as medical history, image data corresponding to injured joints or bones, and various parameters (by way of example) corresponding to a pre-operatively generated surgical plan). The pre-operative surgical planning system 202 may be equivalent to the virtual planning system 102 of Figure 1, and in some examples may generally correspond to a virtual planning system similar or identical to the BLUEPRINT™ system.

[0023] In the example of FIG. 2, the medical facility 204 includes a mixed reality (MR) system 212. In some examples of the present disclosure, the MR system 212 includes one or more processing device(s) (P) 210 to provide functionality described in more detail below. The processing device(s) 210 may also be referred to as a processor(s). Additionally, one or more users of the MR system 212 (e.g., surgeons, nurses, or other healthcare providers) may use the processing device(s) (P) 210 to generate requests for specific surgical plans or other patient information, which are transmitted to the storage system 206 over the network 208. In response, the storage system 206 returns the requested patient information to the MR system 212. In some embodiments, a user may request and receive information using other processing device(s), such as one or more processing devices that are part of the MR system 212 but not part of a visualization device, or one or more processing devices that are part of a visualization device (e.g., visualization device 213) of the MR system 212, or a combination of one or more processing devices that are part of the MR system 212 but not part of a visualization device, as well as one or more processing devices that are part of a visualization device (e.g., visualization device 213) that is part of the MR system 212.

[0024] In some embodiments, multiple users may use the MR system 212 simultaneously. For example, the MR system 212 may be used in a spectator mode with multiple users each using their own visualization device, so that the users can view the same information at the same time and from the same perspective. In some embodiments, the MR system 212 may be used in a mode with multiple users each using their own visualization device, so that the users can view the same information from different perspectives.

[0025] In some examples, the processing device(s) 210 may provide a user interface for displaying data and receiving input from a user of the medical facility 204. The processing device(s) 210 may be configured to control the visualization device 213 to present the user interface. Additionally, the processing device(s) 210 may be configured to control the visualization device 213 to present virtual images, such as 3D virtual models, 2D images, and the like. The processing device(s) 210 may comprise a variety of different processing or computing devices, such as servers, desktop computers, laptop computers, tablets, mobile phones, and other electronic computing devices, or processors within such devices. In some examples, one or more of the processing device(s) 210 may be located remotely from the medical facility 204. In some examples, the processing device(s) 210 reside within the visualization device 213. In some examples, at least one of the processing device(s) 210 is external to the visualization device 213. In some embodiments, one or more of the processing device(s) 210 reside within the visualization device 213 and one or more of the processing device(s) 210 are external to the visualization device 213.

[0026] In the example of FIG. 2, the MR system 212 also includes one or more memory or storage device(s) (M) 215 for storing data and instructions of software that may be executed by the processing device(s) 210. The instructions of the software may correspond to the functionality of the MR system 212 described herein. In some examples, the functionality of a virtual surgical planning application, such as the BLUEPRINT™ system, may also be stored and executed by the processing device(s) 210 in conjunction with the memory storage device(s) (M) 215. For example, the memory or storage system 215 may be configured to store data corresponding to at least a portion of the virtual surgical plan. In some examples, the storage system 206 may be configured to store data corresponding to at least a portion of the virtual surgical plan. In some examples, the memory or storage device(s) (M) 215 resides within the visualization device 213. In some examples, the memory or storage device(s) (M) 215 is external to the visualization device 213. In some embodiments, the memory or storage device(s) (M) 215 comprises a combination of one or more memories or storage devices within the visualization device 213 and one or more memories or storage devices external to the visualization device.

[0027] The network 208 may be equivalent to the network 116. The network 208 may comprise one or more wide area networks, local area networks, and / or global networks (e.g., the Internet) that connect the preoperative surgical planning system 202 and the MR system 212 to the storage system 206. The storage system 206 may comprise one or more databases that may include patient information, medical information, patient image data, and parameters that define the surgical plan. For example, medical images of a patient's diseased or injured bones are typically created preoperatively in preparation for an orthopedic surgical procedure. The medical images may include images of the relevant bone(s) taken along sagittal and coronal planes of the patient's body. The medical images may include x-ray images, magnetic resonance imaging (MRI) images, computed tomography (CT) images, ultrasound images, and / or any other type of 2D or 3D images that provide information about the relevant surgical area. The storage system 206 may also include data identifying the implant components (e.g., type, size, etc.) selected for a particular patient, the surgical guide selected for a particular patient, and details of the surgical procedure, such as entry point, cutting plane, drill axis, reaming depth, etc. The storage system 206 may, for example, be a cloud-based storage system (as shown), may be located at the medical facility 204 or the pre-operative surgical planning system 202, or may be part of the MR system 212 or visualization device (VD) 213.

[0028] The MR system 212 may be used by a surgeon prior to (e.g., pre-op) or during (e.g., intra-op) a surgical procedure to create, review, verify, update, modify, and / or implement a surgical plan. In some examples, the MR system 212 may also be used after (e.g., post-op) a surgical procedure to review the results of the surgical procedure, evaluate whether modifications are necessary, or perform other post-operative tasks. To that end, the MR system 212 may comprise a visualization device 213 that may be worn by the surgeon (as described in further detail below) and operable to display various types of information, such as a 3D virtual image of the patient's diseased, damaged, or post-operative joint, and details of the surgical plan, such as a 3D virtual image of the prosthetic implant components selected for the surgical plan, a 3D virtual image of the entry points for placing the prosthetic components, alignment axes and cutting planes for alignment cuts, or a reaming tool for shaping the bone surface, or a drilling tool for defining one or more holes in the bone surface, (for properly orienting and aligning the prosthetic components, surgical guides, and instruments, and their placement in the damaged joint in the surgical procedure), and any other information that may be useful to the surgeon in carrying out the surgical plan. The MR system 212 may create an image of this information that is perceptible to a user of the visualization device 213 before and / or during the surgical procedure.

[0029] In some embodiments, the MR system 212 includes multiple visualization devices (e.g., multiple instances of the visualization device 213) so that multiple users can simultaneously view the same images and share the same 3D scene. In some such embodiments, one of the visualization devices may be designated as a master device, and the other visualization devices may be designated as observers or bystanders. Any observer device may be redesignated as a master device at any time, depending on the desires of a user of the MR system 212.

[0030] In this manner, FIG. 2 illustrates a surgical planning system including a pre-operative surgical planning system 202 that creates a customized virtual surgical plan to repair a target anatomy of a particular patient. For example, the virtual surgical plan may include a plan for an orthopedic joint repair surgical procedure, such as one of a standard total shoulder arthroplasty or a reverse shoulder arthroplasty. In this example, the details of the virtual surgical plan may include details related to at least one of a glenoid bone preparation or a humerus bone preparation. In some examples, the orthopedic joint repair surgical procedure is one of a stemless standard total shoulder arthroplasty, a stemmed standard total shoulder arthroplasty, a stemless reverse shoulder arthroplasty, a stemmed reverse shoulder arthroplasty, an augmented glenoid standard total shoulder arthroplasty, and an augmented glenoid reverse shoulder arthroplasty.

[0031] The virtual surgical plan may include a 3D virtual model corresponding to a target anatomy of a particular patient and 3D models of one or more tools and / or 3D models of prosthetic components adapted to the particular patient or selected to repair the target anatomy. In some examples, the 3D models may include point clouds or meshes (e.g., polygonal meshes, wireframes, etc.) representing features of the corresponding objects. As an example, a 3D model of a patient's bone may include a point cloud or mesh representing a wall of the bone. As another example, the 3D model of a patient's bone may include a first point cloud or mesh representing an inner wall of the bone and a second point cloud or mesh representing an outer wall of the bone. As another example, a 3D model of a prosthetic component (e.g., an implant) may include a point cloud or mesh representing an outer surface of at least a portion of the prosthetic component (e.g., a portion to be inserted into the bone). As another example, a 3D model of an implant tool may include a point cloud or mesh representing an outer surface of at least a portion of the implant tool (e.g., a portion to be inserted into the bone).

[0032] Further, in the example of FIG. 2, the surgical planning system includes a storage system 206 that stores data corresponding to the virtual surgical plan. The surgical planning system of FIG. 2 also includes an MR system 212 that may include a visualization device 213. In some examples, the visualization device 213 is wearable by a user. In some examples, the visualization device 213 is held by a user or placed on a surface where the user can access it. The MR system 212 may be configured to present a user interface via the visualization device 213. The user interface is visually perceptible to a user using the visualization device 213. For example, in one example, a screen of the visualization device 213 may display real-world images and a user interface on the screen. In some examples, the visualization device 213 may project a virtual holographic image onto a see-through holographic lens and allow the user to see real-world objects in a real-world environment through the lens. In other words, the visualization device 213 may include one or more see-through holographic lenses and one or more display devices that present images to the user through the holographic lenses to present the user interface to the user.

[0033] In some examples, the visualization device 213 is configured to allow a user to manipulate a user interface (visually perceivable by the user when the user is wearing or otherwise using the visualization device 213) to request and view details of a virtual surgical plan for a particular patient, including a 3D virtual model of a target anatomy (e.g., a 3D virtual bone of the target anatomy) and a 3D model of a prosthetic component selected to restore the target anatomy. In some such examples, the visualization device 213 is configured to allow a user to manipulate a user interface to allow a user to intraoperatively view the virtual surgical plan, including (at least in some examples) a 3D virtual model of a target anatomy (e.g., a 3D virtual bone of the target anatomy). In some examples, the MR system 212 may operate in an augmented surgery mode in which the user can intraoperatively manipulate a user interface to allow a user to visually perceive details of the virtual surgical plan projected onto a real environment, e.g., a real anatomy of a target for a particular patient. In this disclosure, the terms real and real world may be used in a similar manner. For example, the MR system 212 may present one or more virtual objects that provide guidance for preparation of a bone surface and placement of a prosthetic implant on the bone surface. The visualization device 213 may present one or more virtual objects in a manner that the virtual objects appear to be overlaid on the patient's actual real-world anatomical objects within the real-world environment, for example, by displaying the virtual object(s) according to the actual real-world patient's anatomical structure as viewed by the user through a holographic lens. For example, the virtual objects may be 3D virtual objects that appear to exist within the real-world environment along with the actual real-world anatomical objects.

[0034] FIG. 3 is a flow chart illustrating exemplary stages of a surgical lifecycle 300. In the embodiment of FIG. 3, the surgical lifecycle 300 begins with a pre-operative phase (302). During the pre-operative phase, a surgical plan is developed. The pre-operative phase is followed by a manufacturing and delivery phase (304). During the manufacturing and delivery phase, patient-specific items, such as parts and equipment required to execute the surgical plan, are manufactured and delivered to the surgical site. In some embodiments, manufacturing of patient-specific items is not required to execute the surgical plan. The intra-operative phase is followed by a manufacturing and delivery phase (306). The surgical plan is executed during the intra-operative phase. In other words, one or more people operate on the patient during the intra-operative phase. The intra-operative phase is followed by a post-operative phase (308). The post-operative phase includes activities that occur after the surgical plan is completed. For example, the patient may be monitored during the post-operative phase for complications.

[0035] As described in this disclosure, the orthopaedic surgical system 100 (FIG. 1) may be used in one or more of the pre-operative phase 302, the manufacturing and delivery phase 304, the intra-operative phase 306, and the post-operative phase 308. For example, the virtual planning system 102 and the planning assistance system 104 may be used in the pre-operative phase 302. The manufacturing and delivery system 106 may be used in the manufacturing and delivery phase 304. The intra-operative guidance system 108 may be used in the intra-operative phase 306. Some of the systems of FIG. 1 may be used in multiple phases of FIG. 3. For example, the medical education system 110 may be used in one or more of the pre-operative phase 302, the intra-operative phase 306, and the post-operative phase 308; the pre-operative and post-operative monitoring system 112 may be used in the pre-operative phase 302 and the post-operative phase 308. The predictive analytics system 114 may be used in the pre-operative phase 302 and the post-operative phase 308.

[0036] As mentioned above, one or more subsystems of the orthopaedic surgical system 100 may include one or more mixed reality (MR) systems, such as the MR system 212 (FIG. 2). Each MR system may include a visualization device. For example, in the example of FIG. 2, the MR system 212 includes the visualization device 213. In some examples, in addition to including a visualization device, the MR system may include external computing resources that support the operation of the visualization device. For example, the visualization device of the MR system may be communicatively coupled to a computing device (e.g., a personal computer, a backpack computer, a smartphone, etc.) that provides the external computing resources. Alternatively, suitable computing resources may be provided on or within the visualization device 213 to perform the required functions of the visualization device.

[0037] FIG. 4 is a schematic diagram of a visualization device 213 for use in an MR system, such as the MR system 212 of FIG. 2, according to one example of the present disclosure. As shown in the example of FIG. 4, the visualization device 213 may comprise various electronic components found in a computer system, including one or more processor(s) 514 (e.g., a microprocessor or other type of processing unit) and memory 516, which may be mounted on or within a frame 518. Additionally, in the example of FIG. 4, the visualization device 213 may comprise a transparent screen 520 that is positioned at eye level when the visualization device 213 is worn by a user. In some examples, the screen 520 may comprise one or more liquid crystal displays (LCDs) or other types of display screens through which a surgeon wearing or otherwise using the visualization device 213 may perceive images through the screen 520. Examples of other displays include organic light emitting diode (OLED) displays. In some examples, the visualization device 213 may operate to project a 3D image onto the user's retina using techniques known in the art.

[0038] In some embodiments, the screen 520 may comprise a see-through holographic lens, sometimes referred to as a waveguide, which allows the user to see real-world objects through (e.g., beyond) the lens and also to see a holographic image projected within the lens and onto the user's retina by a display, such as a liquid crystal on silicon (LCoS) display device, sometimes referred to as a light engine or projector, operating as an example of a holographic projection system 538 in the visualization device 213. In other words, the visualization device 213 may comprise one or more see-through holographic lenses to present virtual images to the user. Thus, in some embodiments, the visualization device 213 may operate to project a 3D image onto the user's retina, for example, via the screen 520 formed by the holographic lens. In this manner, the visualization device 213 may be configured to present a 3D virtual image to the user within the real-world view observed by the screen 520, such that, for example, the virtual image appears to form part of the real-world environment. In some examples, the visualization device 213 may be a Microsoft HOLOLENS™ headset available from Microsoft Corporation (Redmond, Washington, USA), or a similar device, such as a similar MR visualization device including a waveguide. The HOLOLENS™ device may be used to display 3D virtual objects through holographic lenses or waveguides, while allowing a user to see real objects in a real-world scene, i.e., in a real-world environment, through the holographic lenses.

[0039] 4 shows the visualization device 213 as a head-mounted device, the visualization device 213 may have other forms and form factors. For example, in some embodiments, the visualization device 213 may be a handheld smartphone or tablet.

[0040] The visualization device 213 may generate a user interface (UI) 522 visible to the user, for example, as a holographic image projected onto a see-through holographic lens as described above. For example, the UI 522 may include various selectable widgets 524 that allow the user to interact with a mixed reality (MR) system, such as the MR system 212 of FIG. 2. The images presented by the visualization device 213 may include, for example, one or more 3D virtual objects. Details of examples of the UI 522 are described elsewhere in this disclosure. The visualization device 213 may include a speaker or other sensory device 526 that may be positioned adjacent the user's ear. The sensory device 526 may communicate auditory or other perceptible information (e.g., vibration) to assist the user of the visualization device 213.

[0041] The visualization device 213 may also include a transceiver 528 for connecting the visualization device 213 to the processing device 510 and / or the network 208 and / or the computing cloud via a wired communication protocol or a wireless protocol, such as Wi-Fi, Bluetooth, etc. The visualization device 213 also includes various sensors for collecting sensor data, such as one or more optical camera(s) 530 (or other optical sensors) and one or more depth camera(s) 532 (or other depth sensors) mounted on or within the frame 518. In some examples, the optical sensor(s) 530 are operable to scan the geometry of the physical environment (e.g., an operating room) in which a user of the MR system 212 is located and collect two-dimensional (2D) optical image data (either monochrome or color). The depth sensor(s) 532 are operable to provide 3D image data, such as by using time-of-flight, stereo, or other known or future developed techniques to determine depth and thereby generate three-dimensional image data. Other sensors may include motion sensors 533 (eg, inertial mass unit (IMU) sensors, accelerometers, etc.) that assist in tracking motion.

[0042] The MR system 212 may process the sensor data to define geometric landmarks, environmental landmarks, texture landmarks, etc. (e.g., corners, edges or other lines, walls, floors, objects) in the user's environment or "scene" and may detect motion within the scene. As an example, different types of sensor data may be combined or fused so that a user of the visualization device 213 may perceive a 3D image that can be positioned or fixed and / or moved within the scene. When fixed in the scene, the user may walk around the 3D image, view the 3D image from different viewpoints, and manipulate the 3D image within the scene using hand gestures, voice commands, gaze line (or direction), and / or other control inputs. As another example, the sensor data may be processed to enable a user to place 3D virtual objects (e.g., bone models) on observed physical objects (e.g., surfaces, real bones of a patient, etc.) in the scene and / or orient the 3D virtual object with other virtual images displayed in the scene. As yet another example, the sensor data may be processed so that a user may place and anchor a virtual representation of a surgical plan (or other widgets, images, or information) to a surface, such as a wall in a surgical room. Additionally, the sensor data may be used to recognize surgical instruments and the location and / or positioning of those instruments.

[0043] The visualization device 213 may include one or more processors 514 and memory 516, for example, within the frame 518 of the visualization device. In some embodiments, one or more external computing resources 536 process and store information, such as sensor data, instead of or in addition to the in-frame processor(s) 514 and memory 516. In this manner, data processing and storage may be performed by one or more processors 514 and memory 516 within the visualization device 213 and / or some of the processing and storage requirements may be offloaded from the visualization device 213. Thus, in some embodiments, one or more processors that control the operation of the visualization device 213 may be present within the visualization device, for example as processor(s) 514. Alternatively, in some embodiments, at least one of the processors that control the operation of the visualization device 213 may be external to the visualization device, for example as processor(s) 210. Similarly, in some embodiments, the operation of the visualization device 213 may be controlled in part by a combination of one or more processors 514 within the visualization device and one or more processors 210 external to the visualization device.

[0044] For example, in some embodiments, when visualization device 213 is in the context of FIG. 2, processing of sensor data may be performed by processing device(s) 210 associated with memory or storage device(s) (M) 215. In some embodiments, processor(s) 514 and memory 516 mounted on frame 518 may provide sufficient computing resources to process sensor data collected by cameras 530, 532 and motion sensor 533. In some embodiments, sensor data may be processed using Simultaneous Localization and Mapping (SLAM) algorithms, or other known or future developed algorithms, to process and map 2D and 3D image data and track the position of visualization device 213 in the 3D scene. In some embodiments, image tracking may be performed by one or more sensors and processor 514 in visualization device 213 using sensor processing and tracking capabilities provided by the Microsoft HOLOLENS™ system, e.g., substantially conforming to a Microsoft HOLOLENS™ device or similar mixed reality (MR) visualization device.

[0045] In some examples, the MR system 212 may also include user-operated control device(s) 534 that enable a user to operate the MR system 212, use the MR system 212 in a spectator mode (as a master or observer), interact with the UI 522, and / or otherwise provide commands or requests to the processing device(s) 210 or other systems connected to the network 208. By way of example, the control device(s) 234 may comprise a microphone, a touch pad, a control panel, a motion sensor, or other type of control input device with which a user can interact.

[0046] FIG. 5 is a block diagram illustrating exemplary components of a visualization device 213 for use in an MR system. In the example of FIG. 5, the visualization device 213 includes a processor 514, a power supply 600, a display device(s) 602, a speaker 604, a microphone(s) 606, an input device(s) 608, an output device(s) 610, a storage device(s) 612, a sensor(s) 614, and a communication device 616. In the example of FIG. 5, the sensor(s) 616 may include a depth sensor(s) 532, an optical sensor(s) 530, a motion sensor(s) 533, and an orientation sensor(s) 618. The optical sensor(s) 530 may include a camera, such as a red-green-blue (RGB) video camera, an infrared camera, or other type of sensor that forms an image from light. The display device(s) 602 may display an image to present a user interface to a user.

[0047] In some examples, the speaker 604 may form part of the sensory device 526 shown in FIG. 4. In some examples, the display device 602 may include the screen 520 shown in FIG. 4. For example, as discussed with reference to FIG. 4, the display device(s) 602 may include a see-through holographic lens combined with a projector, which allows the user to see real-world objects in the real-world environment through the lens and also to see virtual 3D holographic images projected, for example, by a holographic projection system, onto the lens and onto the user's retina. In this example, the virtual 3D holographic objects may appear to be located within the real-world environment. In some examples, the display device 602 includes one or more display screens, for example, an LCD display screen, an OLED display screen, etc. The user interface may present a virtual image of details of a virtual surgical plan for a particular patient.

[0048] In some examples, a user may interact with and control visualization device 213 in a variety of ways. For example, microphone 606 and associated voice recognition processing circuitry or software may recognize voice commands spoken by the user and, in response, perform any of a variety of actions, such as selecting, activating, or deactivating various functions associated with surgical planning, intra-operative guidance, and the like. As another example, one or more cameras or other optical sensors 530 of sensor 614 may detect and interpret gestures to perform the actions described above. As a further example, sensor 614 may sense a direction of gaze and perform various actions as described elsewhere in this disclosure. In some examples, input device 608 may receive manual input from a user, for example via a handheld controller including one or more buttons, a keypad, a touch screen, a joystick, a trackball, and / or other manual input media, and perform the various operations described above in response to the manual user input.

[0049] As described above, the surgical lifecycle 300 may include a pre-operative phase 302 (FIG. 3). One or more users may use the orthopaedic surgical system 100 in the pre-operative phase 302. For example, the orthopaedic surgical system 100 may include a virtual planning system 102 to assist one or more users in creating a virtual surgical plan that may be customized to a target anatomy of a particular patient. As described herein, the virtual surgical plan may include a three-dimensional virtual model corresponding to the target anatomy of a particular patient and a three-dimensional model of one or more prosthetic components that are adapted to the particular patient or selected to restore the target anatomy. The virtual surgical plan may also include a three-dimensional virtual model of guidance information to guide a surgeon in performing a surgical procedure, for example, in preparing bone surfaces or tissues and placing implantable prosthetic hardware relative to such bone surfaces or tissues.

[0050] 6 is a flow chart illustrating example steps of the pre-operative phase 302 of the surgical lifecycle 300. In other embodiments, the pre-operative phase 302 may include more, fewer, or different steps. Additionally, in other embodiments, one or more of the steps of FIG. 6 may be performed in a different order. In some embodiments, one or more of the steps may be performed automatically within a surgical planning system, such as virtual planning system 102 (FIG. 1) or 202 (FIG. 2).

[0051] In the example of FIG. 6, a model of the region of interest is generated (800). For example, a scan (e.g., a CT scan, an MRI scan, or other type of scan) of the region of interest may be performed. For example, if the region of interest is the patient's shoulder, a scan of the patient's shoulder may be performed. The virtual planning system may generate a virtual model (e.g., a three-dimensional virtual model) of the region of interest based on the scan. Further, pathology in the region of interest may be classified (802). In some examples, the pathology of the region of interest may be classified based on the scan of the region of interest. For example, if the region of interest is a user's shoulder, a surgeon may determine a shoulder problem of the patient based on the scan of the patient's shoulder and provide a shoulder classification to indicate a diagnosis such as, for example, primary glenohumeral osteoarthritis (PGHOA), rotator cuff tear arthropathy (RCTA) instability, significant rotator cuff tear (MRCT), chronic rheumatoid arthritis, post-traumatic arthritis, and osteoarthritis.

[0052] Further, a surgical plan may be selected based on the pathology (804). The surgical plan is a plan that addresses the pathology. For example, in an embodiment where the area of ​​interest is the patient's shoulder, the surgical plan may be selected from an anatomical shoulder arthroplasty, a reverse shoulder arthroplasty, a post-traumatic shoulder arthroplasty, or a modification to a previous shoulder arthroplasty. The surgical plan may then be tailored to the patient (806). For example, tailoring the surgical plan may include selection and / or sizing of surgical items required to perform the selected surgical plan. Further, the surgical plan may be tailored to the patient to address patient-specific issues, such as the presence of osteitis. As described in detail elsewhere in this disclosure, one or more users may use the mixed reality system of the orthopaedic surgical system 100 to tailor the surgical plan to the patient.

[0053] The surgical plan may then be reviewed (808). For example, the attending surgeon may review the surgical plan before it is executed. As described in detail elsewhere in this disclosure, one or more users may use a mixed reality (MR) system of the orthopaedic surgical system 100 to review the surgical plan. In some examples, the surgeon may modify the surgical plan using the MR system by interacting with the UI and displayed elements, for example, to select a different procedure, change the sizing, shape or placement of an implant, or change the angle, depth or amount of cutting or reaming of the bone surface to accommodate the implant.

[0054] 7 illustrates an exemplary surgical process for shoulder surgery in which virtual images can be aligned to physical space using alignment markers attached to a clamping tool. The surgeon may wear or otherwise use a visualization device 213 during each step of the surgical process. In other examples, shoulder surgery may include more, fewer, or different steps. For example, shoulder surgery may include adding bone grafts, adding cement, and / or other steps. In some examples, the visualization device 213 may present virtual guidance to guide a surgeon, nurse, or other user through the steps of the surgical workflow.

[0055] In the embodiment of Figure 7, a surgeon performs a dissection process (1900). During the dissection process, the surgeon makes a series of incisions to expose the patient's shoulder joint. In some embodiments, an MR system (e.g., MR system 212, MR system 1800A, etc.) may assist the surgeon in performing the dissection process, for example, by displaying a virtual guidance image that indicates how and where to make the incisions.

[0056] Further, in the example of FIG. 7 , the surgeon may perform a humerus resection process (1902). During the humerus resection process, the surgeon may remove a portion of the humeral head of the patient's humerus. Removing the portion of the humeral head may allow the surgeon to access the patient's glenoid. Further, removing the portion of the humeral head may allow the surgeon to subsequently replace the portion of the humeral head with a humeral implant that is compatible with the glenoid implant that the surgeon plans to implant in the patient's glenoid.

[0057] As described above, the humerus creation process may provide the surgeon with access to the patient's glenoid. In the example of Figure 7, after performing the humerus creation process, the surgeon may perform an alignment process (1904) to align the virtual glenoid object with the patient's actual glenoid bone in a field of view presented to the surgeon by the visualization device 213.

[0058] 8 illustrates an example of a technique 2500 for aligning a 3D virtual bone model to a patient's actually observed bone structure using physical markers (e.g., any combination of passive and active physical markers). In other words, FIG. 8 is an example of a process flow performed in a mixed reality system, such as the mixed reality system 212 of FIG. 2, for aligning a virtual bone model to an observed bone, performed, for example, by the visualization device 213. The 3D virtual bone model may be a model of all or part of one or more bones. The process flow of FIG. 8 may be executable as part of the alignment process of step 1904 of FIG. 7.

[0059] During operation, the practitioner may place one or more physical markers at specific locations (e.g., alignment markers 900 in FIGS. 9, 11A and 11B below). In some examples, the MR system 212 may output instructions on where the practitioner should place the physical markers. For example, the physical markers may be positioned to rest and bear on the upper surface of the glenoid cavity. The predetermined locations may correspond to specific locations on the virtual model that correspond to the observed bone structure.

[0060] The MR system 212 may utilize data from one or more sensors (e.g., one or more sensors 614 of the visualization device 213 of FIG. 5) to identify (2510) the location of the alignment marker(s) (e.g., the alignment marker 900 of FIGS. 9, 11A, and 11B below). For example, the MR system 212 may use data generated by any combination of the depth sensor 532 and / or the optical sensor 530 to identify a specific location (e.g., coordinates) of the alignment marker(s). As one particular example, the MR system 212 may use optical data generated by the optical sensor 530 to identify a center of gravity of the alignment marker. The MR system 212 may then utilize the depth data generated by the depth sensor 532 and / or the optical data generated by the optical sensor 530 to determine the location and / or orientation of the identified center of gravity. The MR system 212 may determine the distance between the center of gravity and the attachment point of the alignment marker. Based on the determined distance (ie, between the center of gravity and the attachment point) and the determined position / orientation of the center of gravity, the MR system 212 can determine the position / orientation of the attachment point.

[0061] The MR system 212 may register the virtual model and the observed anatomical structure based on the identified position of the registration marker(s) (2512). For example, if the registration marker(s) are placed on the observed bone structure at a location corresponding to a specific location(s) on the virtual model corresponding to the observed bone structure, the MR system 212 may generate a transformation matrix between the virtual model and the observed bone structure 212. This transformation matrix may allow translation along the x-, y-, and z-axes and rotation about the x-, y-, and z-axes of the virtual model, which may enable achieving and maintaining registration between the virtual and observed bones. In some examples, once the registration is completed, the MR system 212 utilizes the results of the registration to perform simultaneous localization and mapping (SLAM) to maintain the alignment of the virtual model to the corresponding observed object.

[0062] In some examples, the practitioner can remove the physical markers (e.g., after alignment is complete). For example, after the MR system 212 completes the alignment process using the physical markers, the MR system 212 may output an indication that the physical markers can be removed. In examples in which the physical markers are removed, the MR system 212 may continue to maintain alignment of the virtual bone model to the observed bone using virtual markers or any other suitable tracking technique.

[0063] In some examples, the practitioner may not remove the physical markers until a later point in the surgical procedure, for example, the practitioner may not remove the physical markers until alignment of the virtual model to the observed bone is no longer required (e.g., after all virtual guidance using alignment has been displayed and the corresponding surgical steps have been completed).

[0064] In some examples, the MR system 212 may be able to maintain alignment between the virtual bone model and the observed bone (e.g., glenoid, humerus, or other bone structure) throughout the procedure. In some cases, however, the MR system 212 may lose or otherwise be unable to maintain alignment between the virtual bone model and the observed bone. For example, the MR system 212 may lose track of the alignment marker(s). This loss may be the result of a number of factors, including, but not limited to, bodily fluids (e.g., blood) occluding the marker, detachment of the marker (e.g., a physical marker moving out of position), etc. Thus, the MR system 212 may periodically determine whether alignment has been lost (2516).

[0065] In some examples, the MR system 212 may determine that alignment has been lost if the confidence distance between the virtual point and the corresponding physical point exceeds a threshold confidence distance (e.g., a clinical value). The MR system 212 may periodically determine the confidence distance as a value representative of the accuracy of the current alignment. For example, the MR system 212 may determine that the distance between the virtual point and the corresponding physical point is less than 3 mm.

[0066] In some examples, the MR system 212 may output a representation of the trust distance. As one example, the MR system 212 may cause the visualization device 213 to display a numerical value of the trust distance. As another example, the MR system 212 may cause the visualization device 213 to display a graphical representation of the trust distance relative to a threshold trust distance (e.g., displaying a green circle if the trust distance is less than half the threshold trust distance, a yellow circle if the trust distance is between half the threshold trust distance and the threshold trust distance, and a red circle if the trust distance is greater than the threshold trust distance).

[0067] In some embodiments, the MR system 212 may utilize the same threshold confidence distance throughout the entire surgical procedure. In some embodiments, the MR system 212 may utilize different threshold confidence distances for various parts of the surgical procedure. For example, the MR system 212 may utilize a first threshold confidence distance for a first set of work steps and a second threshold confidence distance (different from the first threshold confidence distance) for a second set of work steps.

[0068] If the alignment is not lost ("No" branch of 2516), the MR system 212 may continue to display the virtual guidance (2514). However, if the MR system 212 loses the alignment ("Yes" branch of 2516), the MR system 212 may perform one or more operations to realign the virtual bone model to the observed bone. As an example, the MR system 212 may attempt to perform the alignment process automatically without further action from the practitioner. For example, if the physical marker has not been removed. The MR system 212 may perform the alignment process using the physical marker. Alternatively, if the physical marker has been removed (or not placed), the MR system 212 may output a request for the practitioner to place the physical marker. Thus, the MR system 212 may be considered to periodically align the virtual model to the observed bone.

[0069] In some examples, rather than automatically attempting re-registration if alignment is lost, the MR system 212 may selectively perform re-registration based on whether alignment is still needed (2518). In some examples, the MR system 212 may determine that alignment is still needed if additional virtual guidance is displayed. If the MR system 212 determines that alignment is no longer needed (the "No" branch of 2518), the MR system 212 may end the alignment procedure.

[0070] As mentioned above, the MR system 212 may utilize any combination of virtual and physical markers to enable alignment of the virtual model to the corresponding observed structures. The MR system 212 may use any markers to perform the initial alignment, and if necessary, the MR system 212 may use any markers to perform a realignment. The markers used for the initial alignment may be the same or different from the markers used for any realignment.

[0071] In some embodiments, during the initialization phase of the registration process, to improve the accuracy and quality of the registration, the MR system 212 may calculate and display spatial constraints on the user's head pose and orientation. These constraints may be calculated in real time and may depend on the user's position and / or the direction and / or the distance to the observed bone and / or the depth camera characteristics. For example, the MR system 212 may prompt the user to move closer to the observed bone, adjust the head position so that the user's gaze line is perpendicular to the target surface of the observed bone, or make any other adjustments that may help improve the registration process, which may depend on the particular surgical application and / or the attributes of the particular target anatomical structure and / or the characteristics of the optical and depth sensors used in the MR system 212.

[0072] In some embodiments, the depth camera(s) 532 detect distance using structured light or time of flight of an optical signal having an appropriate wavelength. Typically, the wavelength of the optical signal is selected to minimize penetration of the surface of the observed anatomical structure by the optical signal transmitted by the depth camera(s) 532. However, it should be understood that other known or future developed techniques for detecting distance may also be used.

[0073] As described below, the registration techniques described herein may be performed for any pair of virtual models and observed objects. As an example, the MR system may use the registration techniques to register a virtual model of a bone to an observed bone. As another example, the MR system may use the registration techniques to register a virtual model of an implant to an observed implant. The MR system may use the registration techniques to register a virtual model of a tool to an observed tool.

[0074] In some examples, the MR system may perform the registration technique once for a particular pair of virtual model and observed object (e.g., within a particular surgical procedure). For example, the MR system may register a virtual model of the glenoid to the observed glenoid and use this registration to provide virtual guidance for multiple steps of the surgical procedure. In some examples, the MR system may perform the registration technique multiple times for a particular pair of virtual model and observed object (e.g., within a particular surgical procedure). For example, the MR system may first register a virtual model of the glenoid to the observed glenoid and use this registration to provide virtual guidance for one or more steps of the surgical procedure. Then, for example, after material has been removed from the glenoid (e.g., by reaming), the MR system may register another virtual model of the glenoid (accounting for the removed material) to the observed glenoid and use the subsequent registration to provide virtual guidance for one or more other steps of the surgical procedure.

[0075] The registration process may be used in combination with the virtual planning process and / or intraoperative guidance described elsewhere in this disclosure. Thus, in one embodiment, a virtual surgical plan is created or otherwise acquired to repair a target anatomical structure of a particular patient (e.g., a shoulder joint of a particular patient). In the case where a virtual surgical plan is acquired, another computer system creates the virtual surgical plan, and the MR system (e.g., MR system 212) or another computer system acquires the virtual surgical plan from a computer-readable medium, such as a communication medium or a non-transitory storage medium. In this embodiment, the virtual surgical plan may include a 3D virtual model of the target anatomical structure generated based on preoperative image data and prosthetic components selected for the particular patient to repair the target anatomical structure. Further, in this embodiment, a user may perform the virtual surgical plan using the MR system (e.g., MR system 212). In this embodiment, as part of using the MR system, a user may request a virtual surgical plan for a particular patient.

[0076] In addition, the user may view a virtual image of the surgical plan projected into the real environment. For example, the MR system 212 may present 3D virtual objects such that the objects appear to be present in the real environment, e.g., in the patient's real anatomy, as described in various embodiments of this disclosure. In this embodiment, the virtual image of the surgical plan may include one or more of a 3D virtual model of the target anatomy, a 3D model of the prosthetic components, and a virtual image of a surgical workflow for repairing the target anatomy. Furthermore, in this embodiment, the user may align the 3D virtual model with the target real anatomy of a particular patient. The user may then execute the virtually created surgical plan to repair the target real anatomy based on this alignment. In other words, in the augmented surgical mode, the user may use the visualization device to align the 3D virtual model of the target anatomy with the target real anatomy.

[0077] In some examples, as part of registering the 3D virtual model with the target real anatomy, the 3D virtual model may be aligned (e.g., by a user) with the target real anatomy, and a transformation matrix may be generated between the 3D virtual model and the target real anatomy based on the alignment. The transformation matrix provides a coordinate system for transforming the virtually created surgical plan to the target real anatomy. For example, the registration process may allow the user to view a step of the virtual surgical plan projected onto the target real anatomy. For example, the registration of the 3D virtual model with the target real anatomy may generate a transformation matrix that allows the user to view a step of the virtual surgical plan projected onto the target real anatomy (e.g., identifying an entry point for placing a prosthetic implant to repair the target real anatomy).

[0078] Continuing to refer to FIG. 7, after performing the alignment process, the surgeon may perform a reaming axis drilling process (1906). During the reaming axis drilling process, the surgeon may drill a reaming axis guide pin hole in the patient's glenoid to receive the reaming guide pin. At a later stage of the shoulder surgery, the surgeon may insert the reaming axis pin into the reaming axis guide pin hole. In some examples, the MR system (e.g., MR system 212, MR system 1800A, etc.) may present a virtual reaming axis to assist the surgeon in performing the drilling in alignment with the reaming axis, so that the reaming guide pin may be placed in the correct location and orientation.

[0079] The surgeon may perform the reaming axis drilling process in one of a variety of ways. For example, the surgeon may perform a guide-based process to drill the reaming axis pin hole, where a physical guide is placed in the glenoid to guide the drilling of the reaming axis pin hole. In other examples, the surgeon may perform a guide-less process, such as presenting a virtual reaming axis to guide the surgeon to drill the reaming axis pin hole in the proper alignment. The MR system (e.g., MR system 212, MR system 1800A, etc.) may assist the surgeon in performing any of these processes to drill the reaming axis pin hole.

[0080] 7, the surgeon may perform a reaming shaft pin insertion process (1908). During the reaming shaft pin insertion process, the surgeon inserts a reaming shaft pin into a reaming shaft pin hole drilled in the patient's scapula. In some examples, the MR system (e.g., MR system 212, MR system 1800A, etc.) may present virtual guidance information to assist the surgeon in performing the reaming shaft pin insertion process.

[0081] After performing the reaming shank insertion process, the surgeon may perform a glenoid reaming process (1910). During the glenoid reaming process, the surgeon reams the patient's glenoid. Reaming the patient's glenoid may create a suitable surface for installation of a glenoid implant. In some embodiments, to ream the patient's glenoid, the surgeon may attach a reaming bit to a surgical drill. The reaming bit defines an axial cavity along a rotational axis of the reaming bit. The axial cavity has an inner diameter corresponding to an outer diameter of the reaming shank pin. After attaching the reaming bit to the surgical drill, the surgeon may align the reaming bit such that the reaming shank pin is located within the axial cavity of the reaming bit. Thus, during the glenoid reaming process, the reaming bit may spin about the reaming shank pin. In this manner, the reaming shank pin may prevent the reaming bit from wandering during the glenoid reaming process. In some embodiments, multiple tools may be used to ream the patient's glenoid. The MR system (e.g., MR system 212, MR system 1800A, etc.) may present virtual guidance to assist a surgeon or other user in performing a glenoid reaming process. For example, the MR system may assist a user, such as a surgeon, in selecting a reaming bit to use in the glenoid reaming process. In some embodiments, the MR system presents virtual guidance to assist the surgeon in controlling the depth to which the user reams into the glenoid. In some embodiments, the glenoid reaming process includes a paleo-reaming step and a neo-reaming step (reaming various portions of the patient's glenoid).

[0082] Further, in the surgical process of FIG. 7, the surgeon may perform a glenoid implant installation process (1912). During the glenoid implant installation process, the surgeon installs the glenoid implant into the patient's glenoid. In some instances, when the surgeon is performing an anatomical shoulder arthroplasty, the glenoid implant has a concave surface that acts as a replacement for the user's natural glenoid. In other instances, when the surgeon is performing a reverse shoulder arthroplasty, the glenoid implant has a convex surface that acts as a replacement for the user's natural humeral head. In this reverse shoulder arthroplasty, the surgeon may install a humeral implant with a concave surface that slides over the convex surface of the glenoid implant. As with other steps of the shoulder surgery of FIG. 7, the MR system (e.g., MR system 212, MR system 1800A, etc.) may present virtual guidance to assist the surgeon in performing the glenoid installation process.

[0083] In some embodiments, the glenoid implantation process includes securing the glenoid implant to the patient's scapula (1914). In some embodiments, the process of securing the glenoid implant to the patient's scapula includes drilling one or more anchor holes or one or more screw holes in the patient's scapula, placing anchors, such as one or more pegs or keels of the implant, in the anchor hole(s), and / or inserting screws, possibly using cement or other adhesive, through the glenoid implant and screw holes. The MR system (e.g., MR system 212, MR system 1800A, etc.) may present virtual guidance to assist the surgeon in the process of securing the glenoid implant to the glenoid bone, including, for example, virtual guidance indicating which anchor or screw holes to drill or otherwise form in the glenoid and the placement of the anchors or screws in the holes.

[0084] Further, in the example of FIG. 7, the surgeon may perform a humerus preparation process (1916). During the humerus preparation process, the surgeon prepares the humerus for attachment of a humerus implant. If the surgeon is performing an anatomical shoulder arthroplasty, the humerus implant may have a convex surface that acts as a replacement for the patient's natural humeral head. The convex surface of the humerus implant slides within the concave surface of the glenoid implant. If the surgeon is performing a reverse shoulder arthroplasty, the humerus implant may have a concave surface and the glenoid implant has a corresponding convex surface. As described elsewhere in this disclosure, the MR system (e.g., MR system 212, MR system 1800A, etc.) may present virtual guidance information to assist the surgeon in performing the humerus preparation process.

[0085] 7, the surgeon may perform a humerus graft attachment process (1918). During the humerus implant attachment process, the surgeon attaches the humerus implant to the patient's humerus. As described elsewhere in this disclosure, the MR system (such as MR system 212) may present virtual guidance to assist the surgeon in performing the humerus preparation process.

[0086] After performing the humeral implant attachment process, the surgeon may perform an implant alignment process to align the attached glenoid implant with the attached humeral implant (1920). For example, in an instance where the surgeon is performing an anatomical shoulder arthroplasty, the surgeon may nest the convex surface of the humeral implant with the concave surface of the glenoid implant. If the surgeon is performing a reverse shoulder arthroplasty, the surgeon may nest the convex surface of the glenoid implant with the concave surface of the humeral implant. The surgeon may then perform a wound closure process (1922). During the wound closure process, the surgeon may reconnect tissues that were cut during the incision process to close the wound in the patient's shoulder.

[0087] For shoulder arthroplasty applications, the registration process may be initiated by the virtualization device 213 presenting to the user, for example, a 3D virtual bone model of the patient's scapula and glenoid cavity, generated by the surgical planning system 102 from preoperative images of the patient's anatomy. The user may then manipulate the 3D virtual bone model in a manner that aligns and orients the 3D virtual bone model with the patient's real scapula and glenoid cavity that the user is observing in the surgical environment. Thus, in some embodiments, the MR system may receive user input to assist with the initialization and / or registration. However, as noted above, in some embodiments, the MR system may perform the initialization and / or registration process automatically (e.g., without receiving user input to align the 3D bone model). For other types of arthroplasty, such as knee, hip, foot, ankle, or elbow, different relevant bone structures may be displayed as virtual 3D images and aligned and oriented in a similar manner to the patient's actual real anatomy.

[0088] Regardless of the particular type of joint or anatomical structure involved, the selection of the augmented surgical mode initiates a procedure in which a 3D virtual bone model is aligned to the observed bone structures. In general, the alignment procedure can be considered as a classical optimization problem (e.g., minimization or maximization). In the case of a shoulder arthroplasty procedure, the known inputs to the optimization (e.g., minimization) analysis are the 3D geometry of the observed patient's bone (derived from sensor data from the visualization device 213, including depth data from the depth camera(s) 532) and the 3D virtual bone geometry derived during the virtual surgical planning state (such as by using the BLUEPRINT™ system). Other inputs include details of the surgical plan (derived during the virtual surgical planning stage, such as by using the BLUEPRINT™ system), such as the location and orientation of the entry point, the cutting plane, the reaming and / or drilling axis, and the reaming or drilling depth to shape the bone structure, the type, size and shape of the prosthetic components, and the location and orientation where the prosthetic components will be placed, or in the case of a fracture, the way in which the bone structures will be reconstructed.

[0089] Once a particular patient is selected from the welcome page of the UI presented by the MR system 212 (FIG. 4), the surgical planning parameters associated with this patient are connected to the patient's 3D virtual bone model, for example by one or more processors of the visualization device 213. In the augmented surgery mode, the visualization device 213 enables the surgeon to visualize a virtual representation of the patient's surgical planning parameters by aligning the 3D virtual bone model (with the connected pre-planning parameters) to the observed bones.

[0090] The optimization (e.g., minimization) analysis performed to achieve alignment of the 3D virtual bone model with the real bones is generally performed in two phases: an initialization phase and an optimization (e.g., minimization) phase. During the initialization phase, the user uses gaze direction, hand gestures and / or voice commands to align and orient or otherwise adjust the placement of the virtual bones with the observed real bones to achieve approximate alignment of the 3D virtual bone model with the patient's real bones. The initialization phase is described in more detail below. During the optimization (e.g., minimization) phase, an optimization (e.g., minimization) algorithm is executed, as also described in more detail below. This uses information from the optical camera(s) 530 and / or depth camera(s) 532 and / or any other acquisition sensors (e.g., motion sensor 533) to further improve the alignment of the 3D model with the observed anatomical structure of interest. In some embodiments, the optimization (e.g., minimization) algorithm may be any known or future developed minimization algorithm, including, for example, an Iterative Closest Point algorithm or a genetic algorithm.

[0091] Thus, in one embodiment, the mixed reality surgical planning method includes creating a virtual surgical plan for repairing a target anatomy of a particular patient. The virtual surgical plan, including a 3D virtual model of the target anatomy, is created based on preoperative image data and prosthetic components selected for the particular patient to repair the target anatomy. Further, in this embodiment, the method includes using an MR visualization system to perform the virtual surgical plan. In this embodiment, using the MR system may include requesting a virtual surgical plan for the particular patient. Using the MR system also includes displaying a virtual image of the surgical plan projected into the real environment. For example, the visualization device 213 may be configured to present one or more 3D virtual images of the details of the surgical plan projected into the real environment, such that, for example, the virtual image(s) appear to form part of the real environment. The virtual image of the surgical plan may include a 3D virtual model of the target anatomy, a 3D model of the prosthetic components, and a virtual image of a surgical workflow for repairing the target anatomy. Using the MR system may include registering the 3D virtual model with the real anatomical structure of interest of a particular patient. Further, in this example, using the MR system may include executing the virtually created surgical plan to restore the real anatomical structure of interest based on the registration.

[0092] In some embodiments, the method further includes aligning the 3D virtual model with the real anatomical structure of interest without using virtual or physical markers. The method may also include using the alignment to track the movement of the real anatomical structure of interest during the performance of the virtual surgical plan on the real anatomical structure of interest. The movement of the real anatomical structure of interest may be tracked without using tracking markers. In some cases, aligning the 3D virtual model with the real anatomical structure of interest may include aligning the 3D virtual model with the real anatomical structure of interest and generating a transformation matrix based on the alignment between the 3D virtual model and the real anatomical structure of interest. The transformation matrix provides a coordinate system for transforming the virtually created surgical plan to the real anatomical structure of interest. In some embodiments, the aligning may include virtually aligning a point of interest on a surface of the 3D virtual model within a corresponding region of interest on a surface of the real anatomical structure of interest; and adjusting an orientation of the 3D virtual model such that a virtual surface shape associated with the point of interest is aligned with a real surface shape associated with the corresponding region of interest. In some examples, the aligning may further include rotating the 3D virtual model about the user's line of gaze. The region of interest may be an anatomical landmark of the anatomical structure of interest. The anatomical structure of interest may be a shoulder joint. In some examples, the anatomical landmark is a central region of the glenoid fossa.

[0093] In some embodiments, after the registration process is completed, a tracking process may be initiated that continuously and automatically verifies the registration between the 3D virtual bone model and the observed bone structure during the augmented surgery mode. During a surgical procedure, many events may occur (e.g., patient motion, instrument motion, loss of tracking, etc.) that may disturb the registration between the 3D anatomical model and the corresponding observed patient anatomical structure or may impede the ability of the MR system 212 to maintain the registration between the model and the observed anatomical structure. Thus, by performing a tracking function, the MR system 212 may continuously or periodically verify the registration and adjust the registration parameters as necessary. If the MR system 212 detects an improper registration (e.g., patient motion above a threshold), the user may be requested to restart the registration process.

[0094] As described above, the MR system 212 first aligns the observed bone structure with the 3D virtual bone model using the registration markers. The MR system 212 may continue to track the positions of the registration markers and utilize the tracked positions to guide the surgical steps. For example, the MR system 212 may output virtual axes for display at positions relative to the positions of the registration markers. Thus, if the registration markers are rotated or otherwise moved during the procedure, the surgical steps guided by the MR system 212 based on the positions of the registration markers may be performed with less precision. For example, if the registration markers are pushed or rocked away and rotated during the procedure, the MR system 212 may display the virtual axes in an incorrect position on the bone, even though the virtual axes are still displayed in the correct relative position to the registration markers. Thus, it may be desirable to maintain a fixed, non-rotating reference to facilitate providing a stable alignment with minimal interruption to the procedure.

[0095] According to one or more aspects of the present disclosure, the alignment marker may be attached to the bone via a clamping tool. For example, as discussed in more detail below, the clamping tool may include an opposable surface configured to rest against and bear against a surface of the bone. The alignment marker may be attached to the clamping tool. Using the clamping tool to attach the alignment marker to the bone may more firmly attach the alignment marker to the bone. Thus, the techniques of the present disclosure may improve the accuracy of a surgical step that is guided based on the position of the alignment marker.

[0096] 9 and 10 show an example system including an alignment marker attached to a clamping tool, according to one or more aspects of the present disclosure. FIGS. 11 and 12 show an example of a clamping tool, according to one or more aspects of the present disclosure. As shown in FIGS. 9 and 10, the system 900 may include a clamping tool 902 and an alignment marker 904. The clamping tool 902 may be configured to be rigidly attached to a bone. For example, as shown in FIG. 9, the clamping tool 902 may be attached to the coracoid process 906 of the scapula 914.

[0097] The clamping tool 902 may include two sections configured to pivot about an axis. For example, as shown in FIGS. 9 and 10, the clamping tool 902 may include sections 906A and 906B (collectively, "sections 906"). Each section 906 includes a surface configured to rest against and bear against a surface of a bone. For example, section 906A may include face 908A, and section 906B may include face 908B. When section 906 pivots about an axis, face 908A may be considered to be an opposable surface to face 908B. One or both of faces 908A and / or 908B (collectively, "faces 908") may be textured (e.g., to improve grip on bone). For example, as shown in FIGS. 9 and 10, face 908 may include "teeth," although other textures are possible.

[0098] In some embodiments, the clamp tool 902 may include one or more components 912 configured to lock the section 906 of the clamp tool 902 in place. The components 912 may include any components that inhibit movement of the sections 906 to maintain pressure of the surface 908 against the bone. As shown in the embodiments of FIGS. 9 and 10, the components 912 may include a ratchet locking mechanism.

[0099] The alignment marker 904 may comprise multiple markers on multiple surfaces. The markers may facilitate locating the center of gravity of the alignment marker 900 and / or the orientation of the alignment marker 900 in space. The alignment marker 904 may be a polyhedron with markers (e.g., fiducial markers) on one or more sides (e.g., 2, 3, 4, 5 sides, etc.) to facilitate the MR system in establishing relative three-dimensional axes (e.g., x-axis, y-axis, and z-axis). In the example of Figs. 9 and 10, only one marker is shown for simplicity. The marker may be readable by a computer vision system, which in some examples is decodable (e.g., QR code, barcode, image, etc.) to facilitate determining the orientation and position of the alignment marker 904. In some examples, one or more markers may include marks indicative of aspects regarding their location on the alignment marker 904. As an example, a first marker may encode an indication that it is in front of the alignment marker 904. As another example, the second marker may encode an indication that it is on top of the alignment marker 904 .

[0100] In some embodiments, the system 900 may include a secondary attachment mechanism 910. The secondary attachment mechanism 910 may be configured to stabilize the clamp tool 902 (e.g., to further reduce relative movement between the alignment marker 904 and the scapula 914).

[0101] 9 and 11, the auxiliary attachment mechanism 910 may include a pin 918 attached directly to the scapula 914 and a clamping tool 902. The pin 918 may be bent (e.g., a 90 degree bend) such that a first end of the pin 918 is embedded in the bone (e.g., embedded in a separately drilled hole or the pin 918 may be impacted into unprepared bone) and a second end of the pin 918 may be attached directly to the clamping tool 902 (e.g., aligned with the axis about which the section 906 pivots).

[0102] As another example, as shown in Figures 10 and 12, the secondary attachment mechanism 910 may include a body 920 defining a passageway (e.g., passageway 926 in Figure 12) configured to receive a pin 922. The pin 922 itself may be attached directly to the bone (e.g., in a separately drilled hole or the pin 922 may be impacted into unprepared bone). The pin 922 may be attached before or after the clamping tool 902 is attached to the bone. For example, the pin 922 may be drilled into the scapula 914, the secondary attachment mechanism 910 with the clamping tool 902 may be slid under the pin 922, and the section 906 may be adjusted to clamp to the bone.

[0103] In operation, the alignment markers 904 may provide a reference for a transformation matrix used to align virtual objects (e.g., virtual images of a glenoid, etc.) to their corresponding physical objects. For example, an MR system (e.g., MR system 212) may utilize the alignment markers 904 as a reference for outputting intraoperative surgical guidance for a surgical step of a joint repair procedure. The alignment markers may be attached to the bone more securely using a clamping tool to attach the alignment markers to the bone. Thus, the techniques of the present disclosure may improve the accuracy of a surgical step that is guided based on the position of the alignment markers.

[0104] While the present technology has been disclosed with respect to a limited number of examples, those skilled in the art having the benefit of this disclosure will appreciate numerous modifications and variations therefrom. For example, it is contemplated that any reasonable combination of the described embodiments may be implemented. It is therefore intended that the appended claims cover all such modifications and variations that fall within the true spirit and scope of the present invention.

[0105] It should be appreciated that, depending on the embodiment, certain activities or events of any of the techniques described herein may be performed in a different order, or may be added, combined, or omitted entirely (e.g., not all described activities or events are required for the practice of the techniques). Furthermore, in certain embodiments, activities or events may be performed simultaneously rather than sequentially, for example, through multithreading, interrupt processing, or multiple processors.

[0106] In one or more embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted as one or more instructions or codes on a computer-readable medium and executed by a hardware-based processing unit. A computer-readable medium may include a computer-readable storage medium corresponding to a tangible medium, such as a data storage medium, or a communication medium, including any medium that facilitates the transmission of a computer program from one place to another, for example according to a communication protocol. Thus, a computer-readable medium may generally correspond to (1) a non-transitory, tangible computer-readable storage medium, or (2) a communication medium, such as a signal or carrier wave. A data storage medium may be any available medium that can be accessed by one or more computers, or one or more processors, to retrieve instructions, codes, and / or data structures for implementing the techniques described in this disclosure. A computer program product may include a computer-readable medium.

[0107] By way of example, and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if instructions are transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of the medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media, but instead relate to non-transitory, tangible storage media. Disks and magnetic disks as used herein include compact disks (CDs), laser disks, optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks, which usually reproduce data magnetically while disks reproduce data optically by means of a laser. Combinations of the above should also be included within the scope of computer readable media.

[0108] The operations described in this disclosure may be performed by one or more processors, which may be implemented as fixed-function processing circuits, programmable circuits, or a combination thereof, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. A fixed-function circuit refers to a circuit that provides a specific function and is preset to executable operations. A programmable circuit refers to a circuit that can be programmed to perform various tasks and provide flexible functionality to executable operations. For example, a programmable circuit may execute instructions specified by software or firmware, such that the programmable circuit operates in a manner defined by the software or firmware instructions. Although a fixed-function circuit may execute software instructions (e.g., to receive parameters or output parameters), the types of operations that a fixed-function circuit performs are generally immutable. Accordingly, the terms "processor" and "processing circuitry" as used herein may refer to any of the above structures or any other structure suitable for implementing the techniques described herein.

[0109] Various embodiments have been described. These and other embodiments are within the scope of the following claims.

Claims

1. a clamping tool having an opposable surface configured to rest against and bear against a surface of a bone; a mixed reality surgical system alignment marker attached to the clamp tool.

2. The system of claim 1 , wherein the clamping tool has two sections configured to pivot about an axis.

3. The system of claim 1 or claim 2, further comprising an auxiliary mounting mechanism configured to stabilize the clamping tool.

4. The system of claim 3 , wherein the auxiliary attachment mechanism comprises a pin configured to be attached directly to the bone and the clamp tool.

5. The system of claim 3 , wherein the secondary attachment mechanism defines a passageway configured to receive a pin attached directly to the bone.

6. The system of any of claims 2 to 5, wherein the clamping tool further comprises one or more components configured to lock the two sections of the clamping tool in position.

7. The system of claim 6 , wherein the one or more components configured to lock the two sections together comprises a ratcheting assembly.

8. The system of any preceding claim, wherein the alignment marker comprises multiple markers on multiple surfaces.

9. The system of claim 8 , wherein each of the markers comprises a different fiducial marker.

10. The system of any preceding claim, wherein the alignment marker is removable from the clamping tool.

11. The system of any one of claims 1 to 10, wherein the bone is a scapula.

12. The system of claim 11 , wherein the opposable surface is configured to rest against and bear against a surface of the coracoid process of the scapula.

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