System and method for determining impingement risk in hip implant patients using image-based modeling

Abstract

Systems and methods for impingement analysis are disclosed herein. A method includes receiving a three-dimensional model of a human anatomy comprising a spinopelvic joint; receiving input related to a spinopelvic condition of a patient; determining at least one of a sacral slope or a lumbar lordosis of the patient based on the input; classifying the spinopelvic condition of the patient based on at least one of the sacral slope or the lumbar lordosis in a plurality of positions; modifying the three-dimensional model based on the spinopelvic condition and a placement of an implant; performing at least one simulation of one or more activities with the modified three-dimensional model; and displaying an impingement analysis on a display device based on the at least one simulation.

Description

Attorney Docket No. PT-6083-WO-PCT / D031202 SYSTEM AND METHOD FOR DETERMINING IMPINGEMENT RISK IN HIP IMPLANT PATIENTS USING IMAGE-BASED MODELING CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U.S. Provisional Application No. 63 / 619,495 filed on January 10, 2024, which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present disclosure relates generally to methods, systems, and apparatuses for simulating different motor activities related to the pelvis. The disclosed techniques may be applied to, for example, planning hip arthroplasties as well as other surgical interventions. More particularly, the present disclosure relates to methods, systems, and apparatuses for developing dynamic simulations of the human body modeling various spinopelvic pathological condition. BACKGROUND

[0003] Typical total hip arthroplasty (THA) planning currently consists of templating a two-dimensional frontal x-ray of the patient’s joint or using a computed tomography (CT) scan from the patient to correctly size and position implant components on the patient’s anatomy.

[0004] One of the objectives of THA is to restore normal hip function, which includes both mobility and stability. Individual patients may present varying levels of spinopelvic mobility. Limited motion at the spinopelvic joint often results in compensation at the hip, thereby increasing the range of motion at the hip and increasing the risk of impingement. Further, patients may exhibit different types of limitations to spinopelvic mobility (i.e., different spinopelvic conditions) that influence the risk of impingement differently. For example, patients exhibiting a “stuck standing” pelvis position may be more prone to anterior ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 implant impingement, whereas patients exhibiting a “stuck sitting” pelvis position may be more prone to posterior implant impingement.

[0005] Dislocation, which is often driven by impingement, is one of the leading causes for revision surgery. The risk of impingement depends on the post-operative mobility of the patient. A planning tool that can predict post-operative personalized mobility would be the ideal instrument to plan implant selection and placement to minimize the risks of impingement and dislocation.

[0006] In addition, while planning THA, a user may benefit by being informed in real time as to how impingement risk changes based on changes to implant selection and placement. Several CT-based planning tools require the user to manually check if their change produced impingement in positions of interest by either manually moving the virtual joint to the desired position or watching a motion animation. This process makes the planning workflow slow and cumbersome, thereby substantially reducing the utility of the impingement analysis.

[0007] Accordingly, accounting for spinopelvic mobility limitations may assist in optimizing acetabular cup placement by decreasing the risk of impingement in a patient- specific manner. Assessment of acetabular cup placement may be facilitated by simulations of foreseeable activities to determine a likelihood of impingement. For example, simulating activities involving high hip flexion angles (e.g., rising from a chair) may be relevant to identifying a risk of anterior impingement. SUMMARY

[0008] In some embodiments, a computer-implemented method includes receiving, by one or more processors, a three-dimensional model of a human anatomy comprising a spinopelvic joint; receiving, by the one or more processors, input related to a spinopelvic condition of a patient; modifying, by the one or more processors, the three-dimensional model ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 based on the input related to the spinopelvic condition of the patient and a placement of an implant; performing, by the one or more processors, at least one simulation of one or more activities with the modified three-dimensional model; and displaying, by the one or more processors, an impingement analysis on a display device based on the at least one simulation.

[0009] In some embodiments, the method further includes determining, by the one or more processors, at least one of a sacral slope or a lumbar lordosis of the patient based on the input; and classifying, by the one or more processors, the spinopelvic condition of the patient based on at least one of the sacral slope or the lumbar lordosis in a plurality of positions, wherein modifying the three-dimensional model is further based on the spinopelvic condition.

[0010] In some embodiments, the three-dimensional model of the human anatomy includes a plurality of segments and a plurality of joints, wherein the plurality of segments are interconnected by the plurality of joints.

[0011] In some embodiments, classifying the spinopelvic condition of the patient further includes classifying, based on a combination of a seated sacral slope and a standing sacral slope, a spinopelvic balance condition of the patient.

[0012] In some embodiments, classifying the spinopelvic condition of the patient further includes classifying, based on a combination of a standing lumbar lordosis and a flex- seated lumbar lordosis, a spinopelvic balance condition of the patient.

[0013] In some embodiments, classifying the spinopelvic condition of the patient further includes classifying, based on a combination of a standing lumbar lordosis and a relaxed-seated lumbar lordosis, a spinopelvic balance condition of the patient.

[0014] In some embodiments, classifying the spinopelvic condition of the patient further includes classifying a spinopelvic mobility condition of the patient.

[0015] In some embodiments, the spinopelvic mobility condition of the patient is selected from the group consisting of fused, stiff, hypermobile, and normal. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0016] In some embodiments, the input comprises two or more 2D images of the spinopelvic joint of the patient.

[0017] In some embodiments, determining at least one of the sacral slope or the lumbar lordosis of the patient includes identifying a plurality of landmarks in the two or more 2D images and calculating at least one of a sacral slope or a lumbar lordosis of the patient based on the plurality of landmarks.

[0018] In some embodiments, performing at the least one simulation of the one or more activities with the modified three-dimensional model includes transforming the simulation into a coordinate system based on the implant placement.

[0019] In some embodiments, performing the at least one simulation of the one or more activities with the modified three-dimensional model further includes simulating a rotation of a stem of the implant about an axis until impingement between the stem and a cup or liner of the implant occurs.

[0020] In some embodiments, the computer-implemented method further includes simulating a plurality of rotations of the stem and generating a range of motion profile for the plurality of rotations, wherein the range of motion profile indicates angles that can be reached by the stem without impingement with respect to the cup or liner.

[0021] In some embodiments, displaying the impingement analysis includes visualizing a graphical representation of a minimum distance to impingement in reference to each of the one or more activities.

[0022] In some embodiments, displaying the impingement analysis includes displaying the modified three-dimensional model; determining at least one area of bone-on-bone impingement based on the at least one simulation; and highlighting the at least one area of bone-on-bone impingement on the modified three-dimensional model. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0023] In some embodiments, displaying the impingement analysis includes displaying the modified three-dimensional model; determining at least one area of bone-on-implant impingement based on the at least one simulation; and highlighting the at least one area of bone-on-implant impingement on the modified three-dimensional model.

[0024] In some embodiments, displaying the impingement analysis includes receiving a three-dimensional model of the implant; displaying the three-dimensional model of the implant; determining at least one area of implant-on-implant impingement based on the at least one simulation; and highlighting the implant-on-implant of impingement on the three- dimensional model of the implant.

[0025] In some embodiments, the computer-implemented method further includes receiving, by the one or more processors, a modification to a parameter of the implant and updating, by the one or more processors, the at least one simulation of one or more activities with the modified three-dimensional model.

[0026] In some embodiments, the computer-implemented method further includes generating an optimal placement of the implant based on the at least one simulation of one or more activities with the modified three-dimensional model.

[0027] In some embodiments, generating an optimal placement of the implant includes determining a jump distance for the at least one simulation of one or more activities and selecting the optimal placement to maximize the jump distance.

[0028] In some embodiments, a system for impingement analysis includes an input device; a display device; at least one processor; and a non-transitory, computer-readable medium comprising instructions. When executed, the instructions can cause the at least one processor to receive a three-dimensional model of a human anatomy; receive input related to a spinopelvic condition of a patient; determine at least one of a sacral slope or a lumbar lordosis of the patient based on the input; classify the spinopelvic condition of the patient based on at ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 least one of the sacral slope or the lumbar lordosis in a plurality of positions; modify the three- dimensional model based on the spinopelvic condition and a placement of an implant; perform at least one simulation of one or more activities with the modified three-dimensional model; and display an impingement analysis on a display device based on the at least one simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the invention and together with the written description serve to explain the principles, characteristics, and features of the invention. In the drawings:

[0030] FIG. 1 depicts an operating theatre including an illustrative computer-assisted surgical system (CASS) in accordance with an embodiment.

[0031] FIG. 2A depicts illustrative control instructions that a surgical computer provides to other components of a CASS in accordance with an embodiment.

[0032] FIG. 2B depicts illustrative control instructions that components of a CASS provide to a surgical computer in accordance with an embodiment.

[0033] FIG. 2C depicts an illustrative implementation in which a surgical computer is connected to a surgical data server via a network in accordance with an embodiment.

[0034] FIG.3A illustrates example imagery in accordance with an embodiment.

[0035] FIG. 3B illustrates example poses of a three-dimensional model in accordance with an embodiment.

[0036] FIG. 4 illustrates a method of assessing hip joint kinematics of a patient in accordance with an embodiment.

[0037] FIG. 5 illustrates an exemplary computer model of the human anatomy in accordance with an embodiment. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0038] FIG. 6 depicts an illustrative example of various anatomical landmarks identified upon a two-dimensional image of the hip in accordance with an embodiment.

[0039] FIG.7A depicts a measurement of sacral slope in both the standing position and the sitting position on lateral x-ray images in accordance with an embodiment.

[0040] FIG.7B depicts a measurement of lumbar lordosis in both the standing position and the flexed-seated position on lateral x-ray images in accordance with an embodiment.

[0041] FIG.7C depicts a measurement of lumbar lordosis in both the standing position and the relaxed-seated position on lateral x-ray images in accordance with an embodiment.

[0042] FIG. 8 depicts an illustrative motion capture system in accordance with an embodiment.

[0043] FIG.9A illustrates a modeled implant coordinate system in accordance with an embodiment.

[0044] FIG. 9B illustrates an example simulated sweep in which the implant stem rotates about an axis until impingement between the stem and cup or liner occurs.

[0045] FIG. 9C illustrates an example visualization of series of sweeps in a range of motion profile in accordance with an embodiment.

[0046] FIG. 10 depicts an illustrative user interface for evaluating joint kinematic information in accordance with an embodiment.

[0047] FIG. 11 depicts an illustrative user interface for evaluating impingement in accordance with an embodiment.

[0048] FIG. 12 depicts an illustrative user interface that can be interacted with to visualize simple preset motions in one or two directions.

[0049] FIG. 13 illustrates a block diagram of an exemplary data processing system in which embodiments are implemented. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 DETAILED DESCRIPTION

[0050] This disclosure is not limited to the particular systems, devices and methods described, as these may vary. The terminology used in the description is for the purpose of describing the particular versions or embodiments only and is not intended to limit the scope.

[0051] As used in this document, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. Nothing in this disclosure is to be construed as an admission that the embodiments described in this disclosure are not entitled to antedate such disclosure by virtue of prior invention. As used in this document, the term “comprising” means “including, but not limited to.” Definitions

[0052] For the purposes of this disclosure, the term “implant” is used to refer to a prosthetic device or structure manufactured to replace or enhance a biological structure. For example, in a total hip replacement procedure a prosthetic acetabular cup (implant) is used to replace or enhance a patients worn or damaged acetabulum. While the term “implant” is generally considered to denote a man-made structure (as contrasted with a transplant), for the purposes of this specification an implant can include a biological tissue or material transplanted to replace or enhance a biological structure.

[0053] For the purposes of this disclosure, the term “real-time” is used to refer to calculations or operations performed on-the-fly as events occur or input is received by the operable system. However, the use of the term “real-time” is not intended to preclude operations that cause some latency between input and response, so long as the latency is an unintended consequence induced by the performance characteristics of the machine. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0054] For the purposes of this disclosure, the terms “distract,” “distracting,” or “distraction” are used to refer to displacement of a first point with respect to a second point. For example, the first point and the second point may correspond to surfaces of a joint. In some embodiments herein, a joint may be distracted, i.e., portions of the joint may be separated and / or moved with respect to one another to place the joint under tension. In some embodiments, a first portion of the joint be a surface of a scapula and a second portion of the joint may be a surface of a humerus such that separation occurs between the bones of the joint. In additional embodiments, a first portion of the joint may be a first portion of a humeral implant component or a humeral trial implant and a second portion of the joint may be a second portion of the humeral implant component or the humeral trial implant that is movable with respect to the first portion (e.g., a humeral component and a spacer). Accordingly, separation may occur between the portions of the humeral implant component or the humeral trial implant (i.e., intra-implant separation). Throughout the disclosure herein, the described embodiments may be collectively referred to as distraction of the joint.

[0055] Although much of this disclosure refers to surgeons or other medical professionals by specific job title or role, nothing in this disclosure is intended to be limited to a specific job title or function. Surgeons or medical professionals can include any doctor, nurse, medical professional, or technician. Any of these terms or job titles can be used interchangeably with the user of the systems disclosed herein unless otherwise explicitly demarcated. For example, a reference to a surgeon also could apply, in some embodiments to a technician or nurse.

[0056] The systems, methods, and devices disclosed herein are particularly well adapted for surgical procedures that utilize surgical navigation systems, such as the CORI® surgical navigation system. CORI is a registered trademark of SMITH & NEPHEW, INC. of Memphis, TN. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 CASS Ecosystem Overview

[0057] FIG.1 provides an illustration of an example computer-assisted surgical system (CASS) 100, according to some embodiments. As described in further detail in the sections that follow, the CASS uses computers, robotics, and imaging technology to aid surgeons in performing orthopedic surgery procedures such as total knee arthroplasty (TKA) or THA. For example, surgical navigation systems can aid surgeons in locating patient anatomical structures, guiding surgical instruments, and implanting medical devices with a high degree of accuracy. Surgical navigation systems such as the CASS 100 often employ various forms of computing technology to perform a wide variety of standard and minimally invasive surgical procedures and techniques. Moreover, these systems allow surgeons to more accurately plan, track and navigate the placement of instruments and implants relative to the body of a patient, as well as conduct pre-operative and intra-operative body imaging.

[0058] An Effector Platform 105 positions surgical tools relative to a patient during surgery. The exact components of the Effector Platform 105 will vary, depending on the embodiment employed. For example, for a knee surgery, the Effector Platform 105 may include an End Effector 105B that holds surgical tools or instruments during their use. The End Effector 105B may be a handheld device or instrument used by the surgeon (e.g., a CORI® hand piece or a cutting guide or jig) or, alternatively, the End Effector 105B can include a device or instrument held or positioned by a robotic arm 105A. While one robotic arm 105A is illustrated in FIG.1, in some embodiments there may be multiple devices. As examples, there may be one robotic arm 105A on each side of an operating table T or two devices on one side of the table T. The robotic arm 105A may be mounted directly to the table T, be located next to the table T on a floor platform (not shown), mounted on a floor-to-ceiling pole, or mounted on a wall or ceiling of an operating room. The floor platform may be fixed or moveable. In one particular embodiment, the robotic arm 105A is mounted on a floor-to-ceiling pole located between the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 patient's legs or feet. In some embodiments, the End Effector 105B may include a suture holder or a stapler to assist in closing wounds. Further, in the case of two robotic arms 105A, the surgical computer 150 can drive the robotic arms 105A to work together to suture the wound at closure. Alternatively, the surgical computer 150 can drive one or more robotic arms 105A to staple the wound at closure.

[0059] The Effector Platform 105 can include a Limb Positioner 105C for positioning the patient's limbs during surgery. One example of a Limb Positioner 105C is the SMITH AND NEPHEW SPIDER2 system. The Limb Positioner 105C may be operated manually by the surgeon or alternatively change limb positions based on instructions received from the Surgical Computer 150 (described below). While one Limb Positioner 105C is illustrated in FIG.1, in some embodiments there may be multiple devices. As examples, there may be one Limb Positioner 105C on each side of the operating table T or two devices on one side of the table T. The Limb Positioner 105C may be mounted directly to the table T, be located next to the table T on a floor platform (not shown), mounted on a pole, or mounted on a wall or ceiling of an operating room. In some embodiments, the Limb Positioner 105C can be used in non- conventional ways, such as a retractor or specific bone holder. The Limb Positioner 105C may include, as examples, an ankle boot, a soft tissue clamp, a bone clamp, or a soft-tissue retractor spoon, such as a hooked, curved, or angled blade. In some embodiments, the Limb Positioner 105C may include a suture holder to assist in closing wounds.

[0060] The Effector Platform 105 may include tools, such as a screwdriver, light or laser, to indicate an axis or plane, bubble level, pin driver, pin puller, plane checker, pointer, finger, or some combination thereof.

[0061] Resection Equipment 110 (not shown in FIG. 1) performs bone or tissue resection using, for example, mechanical, ultrasonic, or laser techniques. Examples of Resection Equipment 110 include drilling devices, burring devices, oscillatory sawing devices, ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 vibratory impaction devices, reamers, ultrasonic bone cutting devices, radio frequency ablation devices, reciprocating devices (such as a rasp or broach), and laser ablation systems. In some embodiments, the Resection Equipment 110 is held and operated by the surgeon during surgery. In other embodiments, the Effector Platform 105 may be used to hold the Resection Equipment 110 during use.

[0062] The Effector Platform 105 also can include a cutting guide or jig 105D that is used to guide saws or drills used to resect tissue during surgery. Such cutting guides 105D can be formed integrally as part of the Effector Platform 105 or robotic arm 105A or cutting guides can be separate structures that can be matingly and / or removably attached to the Effector Platform 105 or robotic arm 105A. The Effector Platform 105 or robotic arm 105A can be controlled by the CASS 100 to position a cutting guide or jig 105D adjacent to the patient's anatomy in accordance with a pre-operatively or intraoperatively developed surgical plan such that the cutting guide or jig will produce a precise bone cut in accordance with the surgical plan.

[0063] The Tracking System 115 uses one or more sensors to collect real-time position data that locates the patient's anatomy and surgical instruments. For example, for TKA procedures, the Tracking System may provide a location and orientation of the End Effector 105B during the procedure. In addition to positional data, data from the Tracking System 115 also can be used to infer velocity / acceleration of anatomy / instrumentation, which can be used for tool control. In some embodiments, the Tracking System 115 may use a tracker array attached to the End Effector 105B to determine the location and orientation of the End Effector 105B. The position of the End Effector 105B may be inferred based on the position and orientation of the Tracking System 115 and a known relationship in three-dimensional space between the Tracking System 115 and the End Effector 105B. Various types of tracking systems may be used in various embodiments of the present invention including, without ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 limitation, Infrared (IR) tracking systems, electromagnetic (EM) tracking systems, video or image based tracking systems, and ultrasound registration and tracking systems. Using the data provided by the tracking system 115, the surgical computer 150 can detect objects and prevent collision. For example, the surgical computer 150 can prevent the robotic arm 105A and / or the End Effector 105B from colliding with soft tissue.

[0064] Any suitable tracking system can be used for tracking surgical objects and patient anatomy in the surgical theatre. For example, a combination of IR and visible light cameras can be used in an array. Various illumination sources, such as an IR LED light source, can illuminate the scene allowing three-dimensional imaging to occur. In some embodiments, this can include stereoscopic, tri-scopic, quad-scopic, etc. imaging. In addition to the camera array, which in some embodiments is affixed to a cart, additional cameras can be placed throughout the surgical theatre. For example, handheld tools or headsets worn by operators / surgeons can include imaging capability that communicates images back to a central processor to correlate those images with images captured by the camera array. This can give a more robust image of the environment for modeling using multiple perspectives. Furthermore, some imaging devices may be of suitable resolution or have a suitable perspective on the scene to pick up information stored in quick response (QR) codes or barcodes. This can be helpful in identifying specific objects not manually registered with the system. In some embodiments, the camera may be mounted on the robotic arm 105A.

[0065] In some embodiments, specific objects can be manually registered by a surgeon with the system preoperatively or intraoperatively. For example, by interacting with a user interface, a surgeon may identify the starting location for a tool or a bone structure. By tracking fiducial marks associated with that tool or bone structure, or by using other conventional image tracking modalities, a processor may track that tool or bone as it moves through the environment in a three-dimensional model. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0066] In some embodiments, certain markers, such as fiducial marks that identify individuals, important tools, or bones in the theater may include passive or active identifiers that can be picked up by a camera or camera array associated with the tracking system. For example, an IR LED can flash a pattern that conveys a unique identifier to the source of that pattern, providing a dynamic identification mark. Similarly, one- or two-dimensional optical codes (barcode, QR code, etc.) can be affixed to objects in the theater to provide passive identification that can occur based on image analysis. If these codes are placed asymmetrically on an object, they also can be used to determine an orientation of an object by comparing the location of the identifier with the extents of an object in an image. For example, a QR code may be placed in a corner of a tool tray, allowing the orientation and identity of that tray to be tracked. Other tracking modalities are explained throughout. For example, in some embodiments, augmented reality (AR) headsets can be worn by surgeons and other staff to provide additional camera angles and tracking capabilities. In this case, the infrared / time of flight sensor data, which is predominantly used for hand / gesture detection, can build correspondence between the AR headset and the tracking system of the robotic system using sensor fusion techniques. This can be used to calculate a calibration matrix that relates the optical camera coordinate frame to the fixed holographic world frame.

[0067] In addition to optical tracking, certain features of objects can be tracked by registering physical properties of the object and associating them with objects that can be tracked, such as fiducial marks fixed to a tool or bone. For example, a surgeon may perform a manual registration process whereby a tracked tool and a tracked bone can be manipulated relative to one another. By impinging the tip of the tool against the surface of the bone, a three- dimensional surface can be mapped for that bone that is associated with a position and orientation relative to the frame of reference of that fiducial mark. By optically tracking the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 position and orientation (pose) of the fiducial mark associated with that bone, a model of that surface can be tracked with an environment through extrapolation.

[0068] The registration process that registers the CASS 100 to the relevant anatomy of the patient also can involve the use of anatomical landmarks, such as landmarks on a bone or cartilage. For example, the CASS 100 can include a 3D model of the relevant bone or joint and the surgeon can intraoperatively collect data regarding the location of bony landmarks on the patient's actual bone using a probe that is connected to the CASS. Bony landmarks can include, for example, the medial malleolus and lateral malleolus, the ends of the proximal femur and distal tibia, and the center of the hip joint. The CASS 100 can compare and register the location data of bony landmarks collected by the surgeon with the probe with the location data of the same landmarks in the 3D model. Alternatively, the CASS 100 can construct a 3D model of the bone or joint without pre-operative image data by using location data of bony landmarks and the bone surface that are collected by the surgeon using a CASS probe or other means. The registration process also can include determining various axes of a joint. For example, for a TKA the surgeon can use the CASS 100 to determine the anatomical and mechanical axes of the femur and tibia. The surgeon and the CASS 100 can identify the center of the hip joint by moving the patient's leg in a spiral direction (i.e., circumduction) so the CASS can determine where the center of the hip joint is located.

[0069] A Tissue Navigation System 120 (not shown in FIG. 1) provides the surgeon with intraoperative, real-time visualization for the patient's bone, cartilage, muscle, nervous, and / or vascular tissues surrounding the surgical area. Examples of systems that may be employed for tissue navigation include fluorescent imaging systems and ultrasound systems.

[0070] The Display 125 provides graphical user interfaces (GUIs) that display images collected by the Tissue Navigation System 120 as well other information relevant to the surgery. For example, in one embodiment, the Display 125 overlays image information ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 collected from various modalities (e.g., CT, MRI, X-ray, fluorescent, ultrasound, etc.) collected pre-operatively or intra-operatively to give the surgeon various views of the patient's anatomy as well as real-time conditions. The Display 125 may include, for example, one or more computer monitors. As an alternative or supplement to the Display 125, one or more members of the surgical staff may wear an Augmented Reality (AR) Head Mounted Device (HMD). For example, in FIG.1 the Surgeon 111 is wearing an AR HMD 155 that may, for example, overlay pre-operative image data on the patient or provide surgical planning suggestions. In one embodiment, a tracker array-mounted surgical tool could be detected by both the IR camera and an AR headset (HMD) using sensor fusion techniques without the need for any "intermediate" calibration rigs. This near-depth, time-of-flight sensing camera located in the HMD could be used for hand / gesture detection. The headset's sensor API can be used to expose IR and depth image data and carryout image processing using, for example, C++ with OpenCV. This approach allows the relationship between the CASS and the virtual coordinate frame to be determined and the headset sensor data (i.e., IR in combination with depth images) to isolate the CASS tracker arrays. The image processing system on the HMD can locate the surgical tool in a fixed holographic world frame and the CASS IR camera can locate the surgical tool relative to its camera coordinate frame. This relationship can be used to calculate a calibration matrix that relates the CASS IR camera coordinate frame to the fixed holographic world frame. This means that if a calibration matrix has previously been calculated, the surgical tool no longer needs to be visible to the AR headset. However, a recalculation may be necessary if the CASS camera is accidentally moved in the workflow. Various example uses of the AR HMD 155 in surgical procedures are detailed in the sections that follow.

[0071] Surgical Computer 150 provides control instructions to various components of the CASS 100, collects data from those components, and provides general processing for various data needed during surgery. In some embodiments, the Surgical Computer 150 is a ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 general-purpose computer. In other embodiments, the Surgical Computer 150 may be a parallel computing platform that uses multiple central processing units (CPUs) or graphics processing units (GPU) to perform processing. In some embodiments, the Surgical Computer 150 is connected to a remote server over one or more computer networks (e.g., the Internet). The remote server can be used, for example, for storage of data or execution of computationally intensive processing tasks.

[0072] Various techniques generally known in the art can be used for connecting the Surgical Computer 150 to the other components of the CASS 100. Moreover, the computers can connect to the Surgical Computer 150 using a mix of technologies. For example, the End Effector 105B may connect to the Surgical Computer 150 over a wired (i.e., serial) connection. The Tracking System 115, Tissue Navigation System 120, and Display 125 can similarly be connected to the Surgical Computer 150 using wired connections. Alternatively, the Tracking System 115, Tissue Navigation System 120, and Display 125 may connect to the Surgical Computer 150 using wireless technologies such as, without limitation, Wi-Fi, Bluetooth, Near Field Communication (NFC), or ZigBee. Robotic Arm

[0073] In some embodiments, the CASS 100 includes a robotic arm 105A that serves as an interface to stabilize and hold a variety of instruments used during the surgical procedure. For example, in the context of a hip surgery, these instruments may include, without limitation, retractors, a sagittal or reciprocating saw, the reamer handle, the cup impactor, the broach handle, and the stem inserter. The robotic arm 105A may have multiple degrees of freedom (like a Spider device) and have the ability to be locked in place (e.g., by a press of a button, voice activation, a surgeon removing a hand from the robotic arm, or other method).

[0074] In some embodiments, movement of the robotic arm 105A may be effectuated by use of a control panel built into the robotic arm system. For example, a display screen may ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 include one or more input sources, such as physical buttons or a user interface having one or more icons, that direct movement of the robotic arm 105A. The surgeon or other healthcare professional may engage with the one or more input sources to position the robotic arm 105A when performing a surgical procedure.

[0075] A tool or an end effector 105B attached or integrated into a robotic arm 105A may include, without limitation, a burring device, a scalpel, a cutting device, a retractor, a joint tensioning device, or the like. In embodiments in which an end effector 105B is used, the end effector may be positioned at the end of the robotic arm 105A such that any motor control operations are performed within the robotic arm system. In embodiments in which a tool is used, the tool may be secured at a distal end of the robotic arm 105A, but motor control operation may reside within the tool itself.

[0076] The robotic arm 105A may be motorized internally to both stabilize the robotic arm, thereby preventing it from falling and hitting the patient, surgical table, surgical staff, etc., and to allow the surgeon to move the robotic arm without having to fully support its weight. While the surgeon is moving the robotic arm 105A, the robotic arm may provide some resistance to prevent the robotic arm from moving too fast or having too many degrees of freedom active at once. The position and the lock status of the robotic arm 105A may be tracked, for example, by a controller or the Surgical Computer 150.

[0077] In some embodiments, the robotic arm 105A can be moved by hand (e.g., by the surgeon) or with internal motors into its ideal position and orientation for the task being performed. In some embodiments, the robotic arm 105A may be enabled to operate in a "free" mode that allows the surgeon to position the arm into a desired position without being restricted. While in the free mode, the position and orientation of the robotic arm 105A may still be tracked as described above. In one embodiment, certain degrees of freedom can be selectively released upon input from user (e.g., surgeon) during specified portions of the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 surgical plan tracked by the Surgical Computer 150. Designs in which a robotic arm 105A is internally powered through hydraulics or motors or provides resistance to external manual motion through similar means can be described as powered robotic arms, while arms that are manually manipulated without power feedback, but which may be manually or automatically locked in place, may be described as passive robotic arms.

[0078] A robotic arm 105A or end effector 105B can include a trigger or other means to control the power of a saw or drill. Engagement of the trigger or other means by the surgeon can cause the robotic arm 105A or end effector 105B to transition from a motorized alignment mode to a mode where the saw or drill is engaged and powered on. Additionally, the CASS 100 can include a foot pedal (not shown) that causes the system to perform certain functions when activated. For example, the surgeon can activate the foot pedal to instruct the CASS 100 to place the robotic arm 105A or end effector 105B in an automatic mode that brings the robotic arm or end effector into the proper position with respect to the patient's anatomy in order to perform the necessary resections. The CASS 100 also can place the robotic arm 105A or end effector 105B in a collaborative mode that allows the surgeon to manually manipulate and position the robotic arm or end effector into a particular location. The collaborative mode can be configured to allow the surgeon to move the robotic arm 105A or end effector 105B medially or laterally, while restricting movement in other directions. As discussed, the robotic arm 105A or end effector 105B can include a cutting device (saw, drill, and burr) or a cutting guide or jig 105D that will guide a cutting device. In other embodiments, movement of the robotic arm 105A or robotically controlled end effector 105B can be controlled entirely by the CASS 100 without any, or with only minimal, assistance or input from a surgeon or other medical professional. In still other embodiments, the movement of the robotic arm 105A or robotically controlled end effector 105B can be controlled remotely by a surgeon or other medical professional using a control mechanism separate from the robotic arm or robotically controlled ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 end effector device, for example using a joystick or interactive monitor or display control device.

[0079] A robotic arm 105A may be used for holding the retractor. For example, in one embodiment, the robotic arm 105A may be moved into the desired position by the surgeon. At that point, the robotic arm 105A may lock into place. In some embodiments, the robotic arm 105A is provided with data regarding the patient's position, such that if the patient moves, the robotic arm can adjust the retractor position accordingly. In some embodiments, multiple robotic arms may be used, thereby allowing multiple retractors to be held or for more than one activity to be performed simultaneously (e.g., retractor holding & reaming).

[0080] The robotic arm 105A may also be used to help stabilize the surgeon's hand while making a femoral neck cut. In this application, control of the robotic arm 105A may impose certain restrictions to prevent soft tissue damage from occurring. For example, in one embodiment, the Surgical Computer 150 tracks the position of the robotic arm 105A as it operates. If the tracked location approaches an area where tissue damage is predicted, a command may be sent to the robotic arm 105A causing it to stop. Alternatively, where the robotic arm 105A is automatically controlled by the Surgical Computer 150, the Surgical Computer may ensure that the robotic arm is not provided with any instructions that cause it to enter areas where soft tissue damage is likely to occur. The Surgical Computer 150 may impose certain restrictions on the surgeon to prevent the surgeon from reaming too far into the medial wall of the acetabulum or reaming at an incorrect angle or orientation.

[0081] In some embodiments, the robotic arm 105A may be used to hold a cup impactor at a desired angle or orientation during cup impaction. When the final position has been achieved, the robotic arm 105A may prevent any further seating to prevent damage to the pelvis. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0082] The surgeon may use the robotic arm 105A to position the broach handle at the desired position and allow the surgeon to impact the broach into the femoral canal at the desired orientation. In some embodiments, once the Surgical Computer 150 receives feedback that the broach is fully seated, the robotic arm 105A may restrict the handle to prevent further advancement of the broach.

[0083] The robotic arm 105A may also be used for resurfacing applications. For example, the robotic arm 105A may stabilize the surgeon while using traditional instrumentation and provide certain restrictions or limitations to allow for proper placement of implant components (e.g., guide wire placement, chamfer cutter, sleeve cutter, plan cutter, etc.). Where only a burr is employed, the robotic arm 105A may stabilize the surgeon's handpiece and may impose restrictions on the handpiece to prevent the surgeon from removing unintended bone in contravention of the surgical plan.

[0084] The robotic arm 105A may be a passive arm. As an example, the robotic arm 105A may be a CIRQ robot arm available from Brainlab AG. CIRQ is a registered trademark of Brainlab AG, Olof-Palme-Str. 9 81829, München, FED REP of GERMANY. In one particular embodiment, the robotic arm 105A is an intelligent holding arm as disclosed in U.S. Patent Application No.15 / 525,585 to Krinninger et al., U.S. Patent Application No.15 / 561,042 to Nowatschin et al., U.S. Patent Application No. 15 / 561,048 to Nowatschin et al., and U.S. Patent No. 10,342,636 to Nowatschin et al., the entire contents of each of which is herein incorporated by reference. Surgical Procedure Data Generation and Collection

[0085] The various services that are provided by medical professionals to treat a clinical condition are collectively referred to as an "episode of care." For a particular surgical intervention, the episode of care can include three phases: pre-operative, intra-operative, and post-operative. During each phase, data is collected or generated that can be used to analyze ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 the episode of care in order to understand various features of the procedure and identify patterns that may be used, for example, in training models to make decisions with minimal human intervention. The data collected over the episode of care may be stored at the Surgical Computer 150 or the Surgical Data Server 180 as a complete dataset. Thus, for each episode of care, a dataset exists that includes all of the data collectively pre-operatively about the patient, all of the data collected or stored by the CASS 100 intra-operatively, and any post- operative data provided by the patient or by a healthcare professional monitoring the patient.

[0086] As explained in further detail, the data collected during the episode of care may be used to enhance performance of the surgical procedure or to provide a holistic understanding of the surgical procedure and the patient outcomes. For example, in some embodiments, the data collected over the episode of care may be used to generate a surgical plan. In one embodiment, a high-level, pre-operative plan is refined intra-operatively as data is collected during surgery. In this way, the surgical plan can be viewed as dynamically changing in real-time or near real-time as new data is collected by the components of the CASS 100. In other embodiments, pre-operative images or other input data may be used to develop a robust plan preoperatively that is simply executed during surgery. In this case, the data collected by the CASS 100 during surgery may be used to make recommendations that ensure that the surgeon stays within the pre-operative surgical plan. For example, if the surgeon is unsure how to achieve a certain prescribed cut or implant alignment, the Surgical Computer 150 can be queried for a recommendation. In still other embodiments, the pre-operative and intra-operative planning approaches can be combined such that a robust pre-operative plan can be dynamically modified, as necessary or desired, during the surgical procedure. In some embodiments, a biomechanics-based model of patient anatomy contributes simulation data to be considered by the CASS 100 in developing preoperative, intraoperative, and post-operative / rehabilitation procedures to optimize implant performance outcomes for the patient. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0087] Aside from changing the surgical procedure itself, the data gathered during the episode of care may be used as an input to other procedures ancillary to the surgery. For example, in some embodiments, implants can be designed using episode of care data. Example data-driven techniques for designing, sizing, and fitting implants are described in U.S. Patent No. 10,064,686, filed August 15, 2011, and entitled "Systems and Methods for Optimizing Parameters for Orthopaedic Procedures"; U.S. Patent No. 10,102,309, filed July 20, 2012 and entitled "Systems and Methods for Optimizing Fit of an Implant to Anatomy"; and U.S. Patent No. 8,078,440, filed September 19, 2008 and entitled "Operatively Tuning Implants for Increased Performance," the entire contents of each of which are hereby incorporated by reference into this patent application.

[0088] Furthermore, the data can be used for educational, training, or research purposes. For example, using the network-based approach described below in FIG. 2C, other doctors or students can remotely view surgeries in interfaces that allow them to selectively view data as it is collected from the various components of the CASS 100. After the surgical procedure, similar interfaces may be used to "playback" a surgery for training or other educational purposes, or to identify the source of any issues or complications with the procedure.

[0089] Data acquired during the pre-operative phase generally includes all information collected or generated prior to the surgery. Thus, for example, information about the patient may be acquired from a patient intake form or electronic medical record (EMR). Examples of patient information that may be collected include, without limitation, patient demographics, diagnoses, medical histories, progress notes, vital signs, medical history information, allergies, and lab results. The pre-operative data may also include images related to the anatomical area of interest. These images may be captured, for example, using Magnetic Resonance Imaging (MRI), Computed Tomography (CT), X-ray, ultrasound, or any other ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 modality known in the art. The pre-operative data may also comprise quality of life data captured from the patient. For example, in one embodiment, pre-surgery patients use a mobile application ("app") to answer questionnaires regarding their current quality of life. In some embodiments, preoperative data used by the CASS 100 includes demographic, anthropometric, cultural, or other specific traits about a patient that can coincide with activity levels and specific patient activities to customize the surgical plan to the patient. For example, certain cultures or demographics may be more likely to use a toilet that requires squatting on a daily basis.

[0090] FIGS. 2A and 2B provide examples of data that may be acquired during the intra-operative phase of an episode of care. These examples are based on the various components of the CASS 100 described above with reference to FIG.1; however, it should be understood that other types of data may be used based on the types of equipment used during surgery and their use.

[0091] FIG.2A shows examples of some of the control instructions that the Surgical Computer 150 provides to other components of the CASS 100, according to some embodiments. Note that the example of FIG.2A assumes that the components of the Effector Platform 105 are each controlled directly by the Surgical Computer 150. In embodiments where a component is manually controlled by the Surgeon 111, instructions may be provided on the Display 125 or AR HMD 155 instructing the Surgeon 111 how to move the component.

[0092] The various components included in the Effector Platform 105 are controlled by the Surgical Computer 150 providing position commands that instruct the component where to move within a coordinate system. In some embodiments, the Surgical Computer 150 provides the Effector Platform 105 with instructions defining how to react when a component of the Effector Platform 105 deviates from a surgical plan. These commands are referenced in FIG. 2A as "haptic" commands. For example, the End Effector 105B may provide a force to ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 resist movement outside of an area where resection is planned. Other commands that may be used by the Effector Platform 105 include vibration and audio cues.

[0093] In some embodiments, the end effectors 105B of the robotic arm 105A are operatively coupled with cutting guide 105D. In response to an anatomical model of the surgical scene, the robotic arm 105A can move the end effectors 105B and the cutting guide 105D into position to match the location of the femoral or tibial cut to be performed in accordance with the surgical plan. This can reduce the likelihood of error, allowing the vision system and a processor utilizing that vision system to implement the surgical plan to place a cutting guide 105D at the precise location and orientation relative to the tibia or femur to align a cutting slot of the cutting guide with the cut to be performed according to the surgical plan. Then, a surgeon can use any suitable tool, such as an oscillating or rotating saw or drill to perform the cut (or drill a hole) with perfect placement and orientation because the tool is mechanically limited by the features of the cutting guide 105D. In some embodiments, the cutting guide 105D may include one or more pin holes that are used by a surgeon to drill and screw or pin the cutting guide into place before performing a resection of the patient tissue using the cutting guide. This can free the robotic arm 105A or ensure that the cutting guide 105D is fully affixed without moving relative to the bone to be resected. For example, this procedure can be used to make the first distal cut of the femur during a total knee arthroplasty. In some embodiments, where the arthroplasty is a hip arthroplasty, cutting guide 105D can be fixed to the femoral head or the acetabulum for the respective hip arthroplasty resection. It should be understood that any arthroplasty that utilizes precise cuts can use the robotic arm 105A and / or cutting guide 105D in this manner.

[0094] The Resection Equipment 110 is provided with a variety of commands to perform bone or tissue operations. As with the Effector Platform 105, position information may be provided to the Resection Equipment 110 to specify where it should be located when ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 performing resection. Other commands provided to the Resection Equipment 110 may be dependent on the type of resection equipment. For example, for a mechanical or ultrasonic resection tool, the commands may specify the speed and frequency of the tool. For Radiofrequency Ablation (RFA) and other laser ablation tools, the commands may specify intensity and pulse duration.

[0095] Some components of the CASS 100 do not need to be directly controlled by the Surgical Computer 150; rather, the Surgical Computer 150 only needs to activate the component, which then executes software locally specifying the manner in which to collect data and provide it to the Surgical Computer 150. In the example of FIG. 2A, there are two components that are operated in this manner: the Tracking System 115 and the Tissue Navigation System 120.

[0096] The Surgical Computer 150 provides the Display 125 with any visualization that is needed by the Surgeon 111 during surgery. For monitors, the Surgical Computer 150 may provide instructions for displaying images, GUIs, etc. using techniques known in the art. The display 125 can include various portions of the workflow of a surgical plan. During the registration process, for example, the display 125 can show a preoperatively constructed 3D bone model and depict the locations of the probe as the surgeon uses the probe to collect locations of anatomical landmarks on the patient. The display 125 can include information about the surgical target area. For example, in connection with a TKA, the display 125 can depict the mechanical and anatomical axes of the femur and tibia. The display 125 can depict varus and valgus angles for the knee joint based on a surgical plan, and the CASS 100 can depict how such angles will be affected if contemplated revisions to the surgical plan are made. Accordingly, the display 125 is an interactive interface that can dynamically update and display how changes to the surgical plan would impact the procedure and the final position and orientation of implants installed on bone. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0097] As the workflow progresses to preparation of bone cuts or resections, the display 125 can depict the planned or recommended bone cuts before any cuts are performed. The surgeon 111 can manipulate the image display to provide different anatomical perspectives of the target area and can have the option to alter or revise the planned bone cuts based on intraoperative evaluation of the patient. The display 125 can depict how the chosen implants would be installed on the bone if the planned bone cuts are performed. If the surgeon 111 choses to change the previously planned bone cuts, the display 125 can depict how the revised bone cuts would change the position and orientation of the implant when installed on the bone.

[0098] The display 125 can provide the surgeon 111 with a variety of data and information about the patient, the planned surgical intervention, and the implants. Various patient-specific information can be displayed, including real-time data concerning the patient's health such as heart rate, blood pressure, etc. The display 125 also can include information about the anatomy of the surgical target region including the location of landmarks, the current state of the anatomy (e.g., whether any resections have been made, the depth and angles of planned and executed bone cuts), and future states of the anatomy as the surgical plan progresses. The display 125 also can provide or depict additional information about the surgical target region. For a TKA, the display 125 can provide information about the gaps (e.g., gap balancing) between the femur and tibia and how such gaps will change if the planned surgical plan is carried out. For a TKA, the display 125 can provide additional relevant information about the knee joint such as data about the joint's tension (e.g., ligament laxity) and information concerning rotation and alignment of the joint. The display 125 can depict how the planned implants' locations and positions will affect the patient as the knee joint is flexed. The display 125 can depict how the use of different implants or the use of different sizes of the same implant will affect the surgical plan and preview how such implants will be positioned on the bone. The CASS 100 can provide such information for each of the planned bone resections in a TKA 27 ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 or THA. In a TKA, the CASS 100 can provide robotic control for one or more of the planned bone resections. For example, the CASS 100 can provide robotic control only for the initial distal femur cut, and the surgeon 111 can manually perform other resections (anterior, posterior and chamfer cuts) using conventional means, such as a 4-in-1 cutting guide or jig 105D.

[0099] The display 125 can employ different colors to inform the surgeon of the status of the surgical plan. For example, un-resected bone can be displayed in a first color, resected bone can be displayed in a second color, and planned resections can be displayed in a third color. Implants can be superimposed onto the bone in the display 125, and implant colors can change or correspond to different types or sizes of implants.

[0100] The information and options depicted on the display 125 can vary depending on the type of surgical procedure being performed. Further, the surgeon 111 can request or select a particular surgical workflow display that matches or is consistent with his or her surgical plan preferences. For example, for a surgeon 111 who typically performs the tibial cuts before the femoral cuts in a TKA, the display 125 and associated workflow can be adapted to take this preference into account. The surgeon 111 also can preselect that certain steps be included or deleted from the standard surgical workflow display. For example, if a surgeon 111 uses resection measurements to finalize an implant plan but does not analyze ligament gap balancing when finalizing the implant plan, the surgical workflow display can be organized into modules, and the surgeon can select which modules to display and the order in which the modules are provided based on the surgeon's preferences or the circumstances of a particular surgery. Modules directed to ligament and gap balancing, for example, can include pre- and post-resection ligament / gap balancing, and the surgeon 111 can select which modules to include in their default surgical plan workflow depending on whether they perform such ligament and gap balancing before or after (or both) bone resections are performed. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0101] For more specialized display equipment, such as AR HMDs, the Surgical Computer 150 may provide images, text, etc. using the data format supported by the equipment. For example, if the Display 125 is a holography device such as the Microsoft HoloLens™ or Magic Leap One™, the Surgical Computer 150 may use the HoloLens Application Program Interface (API) to send commands specifying the position and content of holograms displayed in the field of view of the Surgeon 111.

[0102] In some embodiments, one or more surgical planning models may be incorporated into the CASS 100 and used in the development of the surgical plans provided to the surgeon 111. The term "surgical planning model" refers to software that simulates the biomechanics performance of anatomy under various scenarios to determine the optimal way to perform cutting and other surgical activities. For example, for knee replacement surgeries, the surgical planning model can measure parameters for functional activities, such as deep knee bends, gait, etc., and select cut locations on the knee to optimize implant placement. One example of a surgical planning model is the LIFEMOD™ simulation software from SMITH AND NEPHEW, INC. In some embodiments, the Surgical Computer 150 includes computing architecture that allows full execution of the surgical planning model during surgery (e.g., a GPU-based parallel processing environment). In other embodiments, the Surgical Computer 150 may be connected over a network to a remote computer that allows such execution, such as a Surgical Data Server 180 (see FIG.2C). As an alternative to full execution of the surgical planning model, in some embodiments, a set of transfer functions are derived that simplify the mathematical operations captured by the model into one or more predictor equations. Then, rather than execute the full simulation during surgery, the predictor equations are used. Further details on the use of transfer functions are described in WIPO Publication No. 2020 / 037308, filed August 19, 2019, entitled "Patient Specific Surgical Method and System," the entirety of which is incorporated herein by reference. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0103] FIG.2B shows examples of some of the types of data that can be provided to the Surgical Computer 150 from the various components of the CASS 100. In some embodiments, the components may stream data to the Surgical Computer 150 in real-time or near real-time during surgery. In other embodiments, the components may queue data and send it to the Surgical Computer 150 at set intervals (e.g., every second). Data may be communicated using any format known in the art. Thus, in some embodiments, the components all transmit data to the Surgical Computer 150 in a common format. In other embodiments, each component may use a different data format, and the Surgical Computer 150 is configured with one or more software applications that enable translation of the data.

[0104] In general, the Surgical Computer 150 may serve as the central point where CASS data is collected. The exact content of the data will vary depending on the source. For example, each component of the Effector Platform 105 provides a measured position to the Surgical Computer 150. Thus, by comparing the measured position to a position originally specified by the Surgical Computer 150 (see FIG. 2B), the Surgical Computer can identify deviations that take place during surgery.

[0105] The Resection Equipment 110 can send various types of data to the Surgical Computer 150 depending on the type of equipment used. Example data types that may be sent include the measured torque, audio signatures, and measured displacement values. Similarly, the Tracking Technology 115 can provide different types of data depending on the tracking methodology employed. Example tracking data types include position values for tracked items (e.g., anatomy, tools, etc.), ultrasound images, and surface or landmark collection points or axes. The Tissue Navigation System 120 provides the Surgical Computer 150 with anatomic locations, shapes, etc. as the system operates.

[0106] Although the Display 125 generally is used for outputting data for presentation to the user, it may also provide data to the Surgical Computer 150. For example, ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 for embodiments where a monitor is used as part of the Display 125, the Surgeon 111 may interact with a GUI to provide inputs which are sent to the Surgical Computer 150 for further processing. For AR applications, the measured position and displacement of the HMD may be sent to the Surgical Computer 150 so that it can update the presented view as needed.

[0107] During the post-operative phase of the episode of care, various types of data can be collected to quantify the overall improvement or deterioration in the patient's condition as a result of the surgery. The data can take the form of, for example, self-reported information reported by patients via questionnaires. For example, in the context of a knee replacement surgery, functional status can be measured with an Oxford Knee Score questionnaire, and the post-operative quality of life can be measured with a EQ5D-5L questionnaire. Other examples in the context of a hip replacement surgery may include the Oxford Hip Score, Harris Hip Score, and WOMAC (Western Ontario and McMaster Universities Osteoarthritis index). Such questionnaires can be administered, for example, by a healthcare professional directly in a clinical setting or using a mobile app that allows the patient to respond to questions directly. In some embodiments, the patient may be outfitted with one or more wearable devices that collect data relevant to the surgery. For example, following a knee surgery, the patient may be outfitted with a knee brace that includes sensors that monitor knee positioning, flexibility, etc. This information can be collected and transferred to the patient's mobile device for review by the surgeon to evaluate the outcome of the surgery and address any issues. In some embodiments, one or more cameras can capture and record the motion of a patient's body segments during specified activities postoperatively. This motion capture can be compared to a biomechanics model to better understand the functionality of the patient's joints and better predict progress in recovery and identify any possible revisions that may be needed.

[0108] The post-operative stage of the episode of care can continue over the entire life of a patient. For example, in some embodiments, the Surgical Computer 150 or other ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 components comprising the CASS 100 can continue to receive and collect data relevant to a surgical procedure after the procedure has been performed. This data may include, for example, images, answers to questions, "normal" patient data (e.g., blood type, blood pressure, conditions, medications, etc.), biometric data (e.g., gait, etc.), and objective and subjective data about specific issues (e.g., knee or hip joint pain). This data may be explicitly provided to the Surgical Computer 150 or other CASS component by the patient or the patient's physician(s). Alternatively, or additionally, the Surgical Computer 150 or other CASS component can monitor the patient's EMR and retrieve relevant information as it becomes available. This longitudinal view of the patient's recovery allows the Surgical Computer 150 or other CASS component to provide a more objective analysis of the patient's outcome to measure and track success or lack of success for a given procedure. For example, a condition experienced by a patient long after the surgical procedure can be linked back to the surgery through a regression analysis of various data items collected during the episode of care. This analysis can be further enhanced by performing the analysis on groups of patients that had similar procedures and / or have similar anatomies.

[0109] In some embodiments, data is collected at a central location to provide for easier analysis and use. Data can be manually collected from various CASS components in some instances. For example, a portable storage device (e.g., USB stick) can be attached to the Surgical Computer 150 into order to retrieve data collected during surgery. The data can then be transferred, for example, via a desktop computer to the centralized storage. Alternatively, in some embodiments, the Surgical Computer 150 is connected directly to the centralized storage via a Network 175 as shown in FIG.2C.

[0110] FIG. 2C illustrates a "cloud-based" implementation in which the Surgical Computer 150 is connected to a Surgical Data Server 180 via a Network 175. This Network 175 may be, for example, a private intranet or the Internet. In addition to the data from the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 Surgical Computer 150, other sources can transfer relevant data to the Surgical Data Server 180. The example of FIG.2C shows three additional data sources: the Patient 160, Healthcare Professional(s) 165, and an EMR Database 170. Thus, the Patient 160 can send pre-operative and post-operative data to the Surgical Data Server 180, for example, using a mobile app. The Healthcare Professional(s) 165 includes the surgeon and his or her staff as well as any other professionals working with Patient 160 (e.g., a personal physician, a rehabilitation specialist, etc.). It should also be noted that the EMR Database 170 may be used for both pre-operative and post-operative data. For example, assuming that the Patient 160 has given adequate permissions, the Surgical Data Server 180 may collect the EMR of the Patient pre-surgery. Then, the Surgical Data Server 180 may continue to monitor the EMR for any updates post- surgery.

[0111] At the Surgical Data Server 180, an Episode of Care Database 185 is used to store the various data collected over a patient's episode of care. The Episode of Care Database 185 may be implemented using any technique known in the art. For example, in some embodiments, a SQL-based database may be used where all of the various data items are structured in a manner that allows them to be readily incorporated in two SQL's collection of rows and columns. However, in other embodiments a No-SQL database may be employed to allow for unstructured data, while providing the ability to rapidly process and respond to queries. As is understood in the art, the term "No-SQL" is used to define a class of data stores that are non-relational in their design. Various types of No-SQL databases may generally be grouped according to their underlying data model. These groupings may include databases that use column-based data models (e.g., Cassandra), document-based data models (e.g., MongoDB), key-value based data models (e.g., Redis), and / or graph-based data models (e.g., Allego). Any type of No-SQL database may be used to implement the various embodiments ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 described herein and, in some embodiments, the different types of databases may support the Episode of Care Database 185.

[0112] Data can be transferred between the various data sources and the Surgical Data Server 180 using any data format and transfer technique known in the art. It should be noted that the architecture shown in FIG.2C allows transmission from the data source to the Surgical Data Server 180, as well as retrieval of data from the Surgical Data Server 180 by the data sources. For example, as explained in detail below, in some embodiments, the Surgical Computer 150 may use data from past surgeries, machine learning models, etc. to help guide the surgical procedure.

[0113] In some embodiments, the Surgical Computer 150 or the Surgical Data Server 180 may execute a de-identification process to ensure that data stored in the Episode of Care Database 185 meets Health Insurance Portability and Accountability Act (HIPAA) standards or other requirements mandated by law. HIPAA provides a list of certain identifiers that must be removed from data during de-identification. The aforementioned de-identification process can scan for these identifiers in data that is transferred to the Episode of Care Database 185 for storage. For example, in one embodiment, the Surgical Computer 150 executes the de- identification process just prior to initiating transfer of a particular data item or set of data items to the Surgical Data Server 180. In some embodiments, a unique identifier is assigned to data from a particular episode of care to allow for re-identification of the data if necessary.

[0114] Although FIGS.2A-C discuss data collection in the context of a single episode of care, it should be understood that the general concept can be extended to data collection from multiple episodes of care. For example, surgical data may be collected over an entire episode of care each time a surgery is performed with the CASS 100 and stored at the Surgical Computer 150 or at the Surgical Data Server 180. As explained in further detail below, a robust database of episode of care data allows the generation of optimized values, measurements, ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 distances, or other parameters and other recommendations related to the surgical procedure. In some embodiments, the various datasets are indexed in the database or other storage medium in a manner that allows for rapid retrieval of relevant information during the surgical procedure. For example, in one embodiment, a patient-centric set of indices may be used so that data pertaining to a particular patient or a set of patients similar to a particular patient can be readily extracted. This concept can be similarly applied to surgeons, implant characteristics, CASS component versions, etc.

[0115] Further details of the management of episode of care data are described in U.S. Patent No. 11,532,402, filed April 13, 2020, and entitled "METHODS AND SYSTEMS FOR PROVIDING AN EPISODE OF CARE," the entirety of which is incorporated herein by reference. Methods of Assessing Impingement Risk in Implant Patients

[0116] Planning applications may include varying forms of spinopelvic consideration combined with an impingement analysis. Some example systems allow the user to manually input parameters measured on standing and relaxed-seated lateral x-rays. These measurements may be used to align the 3D bone models. The user may switch between standing and sitting positions. Starting from one of these two positions, the user may manually set the joint to a desired position. In some embodiments, when implant or bone impingement are present, the impinging areas in the 3D models are highlighted in a particular color, such as red.

[0117] Other example systems may use spinopelvic information within their planning software. For each patient, spinopelvic imagery may be collected. The imagery may include a CT scan and a set of lateral x-rays (e.g., standing, flexed-seated, and step-up). FIG. 3A illustrates example lateral x-rays 301-303 in accordance with an embodiment. The x-rays ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 may be used to take pelvis and spine measurements 304-306. The measurements 304-306 may be used to position a CT-derived 3D model in the poses of the x-rays (e.g., standing, flexed-seated, and step-up). FIG.3B illustrates example poses of the 3D model in accordance with an embodiment. The poses may be tested for impingement.

[0118] Further example systems may measure spinopelvic mobility on standing and relaxed-seated lateral x-rays. A 3D model may be aligned to a standing position using the pelvic tilt measured on the lateral x-ray. Additional activities of daily life (e.g., walking, sitting down, lacing shoes, etc.) may be simulated. It should be noted that in current systems the spinopelvic mobility measurements do not affect the activities of daily life motion and impingement is only detected and visualized by running the activity animation. The systems may be improved by using the spinopelvic mobility of the patient to condition activity of daily life simulations that are used to quantify risk of implant-on-implant impingement.

[0119] As discussed herein, it would be advantageous to have systems and methods for simulating different motor activities in patients exhibiting specific spinopelvic limitations as a tool to assist in planning acetabular cup placement for total hip arthroplasty procedures. Ideally, dynamic simulations of the human body performing different motor activities with different spinopelvic pathological conditions would facilitate a more appropriate assessment of range of motion for the purposes of determining implant placement.

[0120] Referring now to FIG.4, a method of assessing hip joint kinematics of a patient is depicted in accordance with an embodiment. The method includes receiving 405 a computer model of the human anatomy, receiving 410 input related to a spinopelvic condition of the patient (e.g., one or more of a spinopelvic balance and a spinopelvic mobility), classifying 415 the spinopelvic condition of the patient based on the input, conditioning 420 the computer model based on the spinopelvic condition, performing 425 at least one simulation of one or more activities of daily living with the computer model, analyzing 430 ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 impingement in the at least one simulation, and outputting 435 hip joint kinematic information based on the at least one simulation and / or the impingement analysis. In some embodiments, the hip joint kinematic information may be used to assess proposed parameters for a surgical plan for the patient including one or more implants (e.g., make, model, and / or size) and / or one or more implant placements (e.g., position and / or orientation).

[0121] Referring now to FIG.5, an exemplary computer model of the human anatomy is depicted in accordance with an embodiment. The computer model of the human anatomy may be a musculoskeletal model representing an average or generic human body. The computer model may roughly represent a portion or an entirety of the human anatomy as a series of discrete, interconnected segments. In some embodiments, the computer model may comprise a plurality of segments connected by a plurality of joints. The segments and / or joints may be simplified representations of the human anatomy and, as such, may approximate various structures. For example, a single segment (e.g., lower leg and / or lower arm) may represent a plurality of bones of the human anatomy as a single structure. In some embodiments, one or more bones of the human anatomy are excluded entirely from the computer model.

[0122] In some embodiments, the plurality of joints may be major joints of the human anatomy (e.g., hip, knee, etc.). Each joint may connect two or more adjacent segments and may specify the manner and range of movement of the adjacent segments with respect to one another. In some embodiments, the joint may specify the manner and range of movement consistent with a corresponding natural, healthy joint of the human anatomy. In some embodiments, the joint may specify the manner and range of movement consistent with a corresponding joint exhibiting one or more conditions, including but not limited to disease, damage, and / or injury. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0123] As shown in FIG.5, the human anatomy may be represented as 19 discrete segments connected by 18 joints. In some embodiments, the 19 discrete segments may include feet, lower legs, upper legs, lower torso (e.g., the pelvis and the sacral base (S1 vertebra)), central torso (e.g., lumbar portion of the spine), upper torso (e.g., thoracic portion of the spine), neck, head, scapulae, upper arms, lower arms, and / or hands. In some embodiments, the 18 joints may include ankles, knees, hips, lumbar or spinopelvic (e.g., between lower torso and central torso, representing spinopelvic articulation of one or more anatomical joints between the S1 vertebra and the L1 vertebra), thoracic (e.g., between central torso and upper torso, representing articulation of one or more anatomical joints between the L1 vertebra and the T1 vertebra), lower neck (e.g., between upper torso and neck, representing articulation of one or more anatomical joints between the T1 vertebra and the C1 vertebra), upper neck (e.g., between neck and head, imitating articulation between the C1 vertebra and the skull), scapulae (e.g., between upper torso and scapulae), shoulders (e.g., between scapulae and upper arms), elbows, and / or wrists. However, various joints and / or segments described herein may be combined, simplified, and / or omitted based on a particular purpose. For example, where the computer model is used for hip simulation, the arms may be less relevant and may thus be simplified and / or omitted.

[0124] As described above, in some cases, a joint of the computer model may represent a single anatomical joint. In other cases, a joint of the computer model may represent a plurality of anatomical joints as a single articulating joint. For example, the lumbar joint may be generally located at a position corresponding to a joint between the S1 vertebra and the L5 vertebra, but the spinopelvic joint may represent the sum of all lumbar motion of joints between the S1 vertebra and the L1 vertebra. In another example, the thoracic joint may be generally located at a position corresponding to a joint between the L1 vertebra and the T12 vertebra, but the thoracic joint may represent the sum of all motion of ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 joints between the L1 vertebra and the T1 vertebra. In another example, the lower neck joint may be generally located at a position corresponding to a joint between the T1 vertebra and the C7 vertebra, but the lower neck joint may represent the sum of all motion of joints between the T1 vertebra and the C1 vertebra. Additional anatomical joints may be combined in a single represented joint of the computer model as would be apparent to a person having an ordinary level of skill in the art.

[0125] Further, some joints and / or segments described herein may include a greater degree of detail and / or may be divided into a plurality of joints and / or segments to provide greater resolution and accuracy to specific regions of the human anatomy based on a particular purpose. For example, where the computer model is used for hip simulation, the hip joints, lumbar or spinopelvic joint, knee joints, and / or additional joints may be modified as described. For example, the spine may be divided into a greater number of segments and joints to represent the vertebrae of the spine more precisely.

[0126] In some embodiments, the computer model may further comprise ligaments and other soft tissue structures to further improve the ability of the model to predict risk of impingement and dislocation. For example, the hip capsule may be included as a combination of 1D, 2D, and / or 3D elements to represent its contribution to resistance to dislocation. In some cases, tensioning of the hip capsule may inform the surgeon regarding medialization and lateralization of the cup and / or additional implant parameters that may affect hip ligament laxity.

[0127] In some embodiments, the properties of the soft tissue structures around the simulated joint may be altered to simulate changes in state due to injury, malfunction, and / or surgery. For example, stiffness and laxity properties of the hip capsule may be altered in a particular region (e.g., anterior region) to simulate a surgical cut through the tissue and / or subsequent surgical repair. In some embodiments, the surgical cut and / or repair may simulate ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 a planned surgical approach (e.g., posterior approach) for the hip replacement procedure. Accordingly, expected post-operative conditions of the soft tissue may be accounted for to provide greater accuracy to simulated hip conditions of the computer model. The computer model may account for additional or alternative changes in soft tissue properties as would be apparent to a person having an ordinary level of skill in the art.

[0128] In some embodiments, the computer model may further comprise muscles to correctly capture their force-generating capacity and predict contact forces at the implant during the simulated activities of daily living. In some embodiments, the muscles may be included as unidimensional elements that produce force to move the segments. In some embodiments, the muscles may be included as 3D elements that additionally capture relative translation between soft tissue structures and distributed pressure on implant components. In some embodiments, muscle elements may be altered to consider the surgical approach and / or simulate muscle weakness, lack of integrity, and other conditions in a similar manner as described previously for the hip capsule.

[0129] The input related to the spinopelvic condition of the patient may take a variety of forms. In some embodiments, receiving 410 input related to the spinopelvic condition of the patient includes obtaining one or more lateral 2D images (e.g., x-rays), such as those depicted in FIG.3A, of the spinopelvic joint of the patient. For example, the input may include a lateral 2D image of the patient in a standing position and / or a lateral 2D image of the patient in a sitting position.

[0130] Based on the lateral 2D images, the spinopelvic balance and / or spinopelvic mobility of the patient may be classified 415. For example, sacral slope (also referred to as sacral tilt) and / or lumbar lordosis may be used to classify 415 the spinopelvic condition of the patient. Sacral slope (SS) or sacral tilt (ST), which is defined as the angle between the endplate of the S1 vertebra and the horizontal plane, or lumbar lordosis (LL), which is ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 defined as the curve of the lower spine, may be determined from the lateral 2D images and used to classify 815 the spinopelvic balance and / or spinopelvic mobility of the patient.

[0131] In some embodiments, a user may manually provide a classification 415 for the spinopelvic balance and / or spinopelvic mobility of the patient.

[0132] In some embodiments, sacral slope may be determined in each 2D image by landmarking the 2D images. For example, user input may be provided through an input device (e.g., a touchscreen of a mobile device displaying the 2D images) to identify a plurality of anatomical landmarks on the patient anatomy.

[0133] Referring now to FIG.6, an illustrative example of various anatomical landmarks identified upon a 2D image of the hip is depicted in accordance with an embodiment. In some embodiments, landmarking includes identifying a location of a superior / posterior S1 endplate 601 and / or a location of an inferior / anterior S1 endplate 602. In some embodiments, landmarking further includes identifying a location of one or more of a hip center 603, a posterior acetabulum 604, and an anterior acetabulum 605. Additional or alternate anatomical landmarks may be identified during landmarking as would be apparent to one having an ordinary level of skill in the art. In some embodiments, the landmarks are identified based on user input. In some embodiments, a computing device, such as a processor of the system as further described herein, may automatically identify one or more landmarks based on historical image data and machine learning techniques.

[0134] As described herein, the sacral tilt in each 2D image may be determined based on the identified landmarks. For example, an endplate orientation line 606 may be formed between the superior / posterior S1 endplate 601 and the inferior / anterior S1 endplate 602 as shown in FIG.6 to define an orientation of the S1 endplate. Thereafter, an angle between the endplate orientation line 606 and a horizontal line 607 may be measured to ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 calculate the sacral tilt. For example, in the 2D image of FIG.6, the sacral tilt (ST) is calculated as 44°.

[0135] FIG.7A depicts a measurement of sacral slope in both the standing position and the sitting position on lateral x-ray images in accordance with an embodiment. In some embodiments, spinopelvic balance may be classified as “stuck standing,” “stuck sitting,” kyphotic, or normal. However, additional medically recognized conditions related to spinopelvic balance may be included in the user input as would be apparent to a person having an ordinary level of skill in the art. Furthermore, in some embodiments, spinopelvic mobility may be classified as fused, stiff, hypermobile, or normal. However, additional medically recognized conditions related to spinopelvic mobility may be included in the user input as would be apparent to a person having an ordinary level of skill in the art.

[0136] Each of the described classifications of spinopelvic balance may be defined by the sacral slope in the standing position and / or the sitting position. In some embodiments, the “stuck standing” classification is defined by a sacral slope of greater than 30° in both the standing position and the sitting position. In some embodiments, the “stuck sitting” classification is defined by a sacral slope of less than 30° in both the standing position and the sitting position. In some embodiments, the kyphotic classification is defined by a sacral slope of less than 5° in the sitting position. In some embodiments, the normal classification is defined by any sacral slopes that do not fall in the remaining spinopelvic balance classifications. However, it is contemplated that the definitions of each classification may be varied and the methods described herein may be carried out in substantially the same manner with minor modifications as would be apparent to a person having an ordinary level of skill in the art. Accordingly, a sacral slope of the patient in a standing position and / or a sacral slope of the patient in a sitting position may be used to classify 415 the spinopelvic balance of the patient. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0137] Each of the described classifications of spinopelvic mobility may be defined by a difference or change in the sacral slope between the standing position and the sitting position. In some embodiments, the fused classification is defined by a change in sacral slope of less than or equal to 5°. In some embodiments, the stiff classification is defined by a change in sacral slope of greater than 5°, but less than or equal to 10°. In some embodiments, the hypermobile classification is defined by a change in sacral slope of greater than 30°. In some embodiments, the normal classification is defined by any change in sacral slope that does not fall in the remaining spinopelvic mobility classifications (e.g., greater than 10°, but less than or equal to 30°). However, it is contemplated that the defined ranges for each classification may be varied and the methods described herein may be carried out in substantially the same manner with minor modifications as would be apparent to a person having an ordinary level of skill in the art. Accordingly, a sacral slope of the patient in a standing position and a sacral slope of the patient in a sitting position may be used to classify 415 the spinopelvic mobility of the patient based on a change in the sacral slope. Referring once again to FIG.7A, a change in sacral slope may be deduced from lateral x-ray images to classify the spinopelvic mobility of the patient.

[0138] While sacral slopes may be determined based on imaging as described herein, the input may be received in alternative forms that directly indicate the sacral slope in the standing position and / or the sitting position, thereby simplifying the classification. In some embodiments, receiving 410 input includes receiving user input indicating one or more sacral slope angles associated with the patient. For example, the input may include a sacral slope of the patient in a standing position and / or a sacral slope of the patient in a sitting position. Accordingly, classifying 415 the spinopelvic balance and / or the spinopelvic mobility of the patient may be completed based on the sacral slopes supplied by the user input. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0139] Furthermore, while a spinopelvic balance and / or spinopelvic mobility of the patient may be determined based on sacral slope values, the input may take alternative forms that directly indicate the classification of the spinopelvic condition, thereby eliminating the need for a classifying step. In some embodiments, receiving 410 input includes receiving user input indicating a classification of the spinopelvic balance and a classification of the spinopelvic mobility of the patient. In such embodiments, the steps of receiving 410 input and classifying 415 the spinopelvic condition may be combined into a single step where the input includes an indication of the spinopelvic condition.

[0140] Referring once again to FIG.6, various additional angles may be determined in each 2D image based on the identified landmarks 601-605. In some embodiments, a pelvic incidence (PI) may be calculated as an angle formed by a first vector 608 and a second vector 609. The first vector 609 may comprise a line joining the bicoxo-femoral axis (i.e., the hip center 603) to a midpoint of the endplate orientation line 606. The second vector 609 may comprise a line perpendicular to the endplate orientation line 606. An angle between the first vector 608 and the second vector 609 may be measured to calculate the PI. For example, in the 2D image of FIG.6, the PI is calculated as 73°. In some embodiments, a pelvic femoral angle (PFA) may be calculated as an angle formed by the first vector 608 and a third vector 610 that parallels the femoral diaphysis. For example, in the 2D image of FIG.6, the PFA is calculated as 20°. In some embodiments, an anti-inclination angle (AI) may be calculated as an angle formed by an acetabular orientation line 611 (i.e., formed between the posterior acetabulum 604 and the anterior acetabulum 605) and the horizontal 607. For example, in the 2D image of FIG.6, the AI is calculated as 52°. In some embodiments, a sacral acetabular angle (SAA) may be calculated as an angle formed by an acetabular orientation line 611 and an extension of the endplate orientation line 606. For example, in the 2D image of FIG.6, the SAA is calculated as 96°. Additional or alternative angles may be calculated from the 2D ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 images as would be apparent to a person having an ordinary level of skill in the art. In some embodiments, the angles are calculated based on user input. In some embodiments, a computing device, such as a processor of the system as further described herein, may automatically calculate one or more angles based on the identified landmarks and / or machine learning techniques. The various angles may be used to classify the mobility of the patient and identify limitations thereto as would be apparent to a person having an ordinary level of skill in the art. Such mobility information may be incorporated into the computer model as described herein.

[0141] FIG.7B depicts a measurement of lumbar lordosis in both the standing position and the flexed-seated position on lateral x-ray images in accordance with an embodiment. The lumbar lordosis of the patient in a standing position and / or flex-seated position may be used to classify 415 the spinopelvic balance of the patient. The differencebetween the standing LL and flex-seated LL values ( LLf) may be calculated. In someembodiments, the LLf may be used as a classifier. For example, a LLf greater than 20° may be classified as normal and a LLf less than 20° may be classified as stiff.

[0142] FIG.7C depicts a measurement of lumbar lordosis in both the standing position and the relaxed-seated position on lateral x-ray images in accordance with an embodiment. The lumbar lordosis of the patient in a standing position and / or relaxed-seated position may be used to classify 415 the spinopelvic balance of the patient. The differencebetween the standing LL and relaxed-seated LL values ( LLr) may be calculated. In someembodiments, the LLrmay be used as a classifier. For example, a LLrless than 10° may be classified as stiff, a LLr between 10° and 30° may be classified as normal, and a LLr greater than 30° may be classified as hypermobile. Patients with stiff and / or hypermobile spines may be associated with higher rates of impingement and / or dislocation. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0143] In certain embodiments, the system may allow a user to select between different classifiers for spinopelvic mobility. The classifier options may include one or more of the classifiers illustrated in FIGS.7A-7C. As noted herein, different classifiers may require different imagery (e.g., relaxed vs. flexed seated) to be collected. In some embodiments, the system may prompt the collection of specific imagery in response to the selection of a classifier. In other embodiments, the user can supply previously captured imagery and the system may limit classifier options based on the available imagery.

[0144] In some embodiments, additional patient-specific measurements beyond the described spinopelvic measurements may be used as inputs to the computer model to condition the computer model as described further herein, thereby customizing the simulations to a specific patient. For example, input data may include measurements, dimensions, geometries, and / or landmark locations for the patient anatomy. In some embodiments, the input data may be received and / or determined based on imaging data including but not limited to, computed tomography (CT), magnetic resonance (MR), and ultrasound. In some embodiments, imaging data may be used to reconstruct bone and / or soft tissue geometries, which can be used to customize the computer model. For example, femur and pelvis geometries may be reconstructed from a CT scan of the hip and inform the computer model on patient-specific input and output variables, including, but not limited to, femur anteversion, bone-on-bone impingement, and soft-tissue impingement. Accordingly, mobility in the computer model may more accurately replicate the movement of the specific patient and account for limitations thereto in order to accurately simulate range of motion.

[0145] Referring once again to FIG.4, conditioning 420 the computer model based on the spinopelvic condition may comprise modifying the computer model to represent the spinopelvic condition of the patient (i.e., the pathological behavior associated with the classification of the spinopelvic condition of the patient). For example, conditioning 420 the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 computer model may comprise limiting the motion of the spinopelvic joint of the computer model consistent with the spinopelvic balance and the spinopelvic mobility of the patient. In some embodiments, where the input includes lateral 2D images, the motion of the spinopelvic joint may be limited to a range based on the lateral 2D images. For example, the motion of the spinopelvic joint may be limited to the range between the sacral slopes of the standing position and the sitting position based on the lateral 2D images. In some embodiments, where the input includes sacral slope values, the motion of the spinopelvic joint may be limited to a range based on the sacral slope values. In some embodiments, where the input includes classification of the spinopelvic balance and / or spinopelvic mobility, the motion of the spinopelvic joint may be limited to a range based on standard or average values for the spinopelvic balance and / or spinopelvic mobility. For example, the motion of the spinopelvic joint may be limited to a range that is typical for an individual with the indicated spinopelvic condition.

[0146] The manners of conditioning 420 the computer model as described herein may, in some instances, result in underestimating spinopelvic mobility and thus limiting motion of the spinopelvic joint to a greater degree than presented in the patient. For example, input sacral slope values and / or sacral slope values determined from lateral 2D images may not represent the maximum boundaries of motion of the spinopelvic joint. However, it may be preferable to underestimate spinopelvic mobility rather than to overestimate spinopelvic mobility, thereby accounting for a worst-case scenario in terms of hip motion and risk of impingement (i.e., by using the most limited assessment of spinopelvic mobility). Accordingly, assuming the received and / or determined sacral slope values represent maximum boundaries provides a conservative modeling approach.

[0147] Further, it should be understood that the assessment of the motion of the spinopelvic joint as discussed herein refers to motion in the sagittal plane and may not ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 account for mobility in the transverse plane and / or frontal plane. In some embodiments, where activities of daily living that occur substantially in the sagittal plane are being assessed as described herein, the computer model and the resultant joint kinematic information produced therewith may not be sensitive to mobility in the transverse plane and / or frontal plane. In some embodiments, mobility of the spinopelvic joint of the patient in the transverse plane and / or frontal plane may be fixed, left unconstrained, or limited in accordance with standard or average values for spinopelvic mobility in the respective planes. In some embodiments, additional information associated with the mobility in the transverse plane and / or frontal plane may be received and used to condition the computer model accordingly.

[0148] Referring once more to FIG.4, performing 425 at least one simulation of one or more activities of daily living with the computer model may take a variety of forms. In some embodiments, the computer model may simulate 425 activities of daily living including but not limited to sitting down, standing up, laying down, rising up from a laying position, walking on a flat surface, walking on an inclined and / or declined surface, walking up a flight of stairs, walking down a flight of stairs, crouching, bending over, and / or kneeling. Further activities of daily living may include spine motion in the sagittal plane. Examples may include twist and lateral bending of the spine such as reaching out behind, pivoting, a golf swing, and a reach to the side from a seated position.

[0149] The simulation may account for the limitations of the spinopelvic condition. For example, where the motion of the spinopelvic joint is constrained due to a specific condition (e.g., spinopelvic balance and / or spinopelvic mobility as described herein), a specific pose or motion associated with an activity of daily living may be performed by compensating with a greater range of motion at the hip joint than in a normal patient. Accordingly, the computer model may limit motion of the spinopelvic joint consistent with ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 the spinopelvic condition and simulate the activities of daily living by enacting a greater degree of motion at the hip joint.

[0150] In some embodiments, the movement of the hip joint through each activity may be assessed, i.e., a relative orientation of the pelvis segment and the upper leg segment may be determined. Accordingly, the computer model may be used to determine a range of motion associated with each activity of daily living under the limitations of the spinopelvic condition. In some embodiments, the activities of daily living selected for assessment may comprise activities that occur substantially in the sagittal plane with respect to the spinopelvic joint as described herein. However, the activities of daily living may nonetheless comprise substantial motion of the hip joint in additional planes.

[0151] In some embodiments, the at least one simulation may be performed 425 based on motion capture marker data. The simulation may rely on the motion capture data to recreate hip joint kinematics consistent with natural biomechanics of the human body under the indicated spinopelvic condition. In some embodiments, motion capture data may be collected from one or more subjects as part of an experimental setup in a motion capture laboratory. The motion capture data may be used to develop the biomechanics of the computer model based on the principles of inverse kinematics, thereby enabling the use of the computer model to simulate patient-specific biomechanics based on an indicated spinopelvic condition.

[0152] Referring now to FIG.8, an illustrative motion capture system is depicted in accordance with an embodiment. Physical markers may be fixed on the skin of one or more subjects in correspondence to known anatomical landmarks. The locations of the physical markers may be recorded by cameras or other sensors of a motion capture system. In some embodiments, the physical markers are reflective markers, and the cameras are configured to detect the light from the reflective markers. Virtual markers corresponding to each of the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 physical markers may be positioned within the computer model in correspondence to the same anatomical landmarks.

[0153] The one or more subjects may perform a variety of activities associated with daily living, e.g., sitting down, standing up, laying down, rising up from a laying position, walking on a flat surface, walking on an inclined and / or declined surface, walking up a flight of stairs, walking down a flight of stairs, crouching, bending over, kneeling, etc. The motion capture system may collect location information for each of the physical markers throughout the activities, and a mathematical algorithm (i.e., inverse kinematics algorithm) may be used to move the segments and joints of the computer model in a manner consistent with the movement of the one or more subjects by minimizing the differences in the positions of the physical markers and the corresponding virtual markers.

[0154] In some embodiments, methodologies alternative to motion capture may be used to collect patient motion data and drive the computer model simulations. For example, technologies including, but not limited to, video-fluoroscopy, stereo-radiography, goniometers, skin stretch sensors, inertial measurement units, accelerometers, and gyroscopes. Patient motion collected with these methodologies may be used to drive the whole computer model or a portion of it.

[0155] In some embodiments, in order to perform inverse kinematics, the computer model is scaled to the dimensions of each subject from the motion capture data collection. The distance between the physical markers detected by the motion capture system may be used to estimate the dimensions of segments of the computer model. For example, the distance between the marker placed at the knee and the marker placed at the ankle may be used to calculate the length of the subject's lower leg and inform the scaling of the model. In another example, the pelvis (lower torso) of the model may be scaled using the markers attached to it, which may also scale the hip joint center location. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0156] In some embodiments, the mathematical algorithm may implement “unconstrained inverse kinematics,” in which each segment of the computer model follows the movement of the virtual markers attached thereto (informed by the movement of the corresponding physical markers as detected by the motion capture system), and each segment moves independently from other segments. However, in some embodiments, the mathematical algorithm may implement “constrained inverse kinematics,” in which relative motion of segments may be constrained by the joints and thus limited to specific types of motion indicated by the joints. For example, a hip joint and / or a knee joint may limit relative motion by permitting rotation and restricting translation between the segments. Additional ways of carrying out the development of the biomechanics of the computer model are described in Lu, T. W. and O'Connor, J. J., “Bone Position Estimation from Skin Marker Coordinates Using Global Optimisation with Joint Constraints,” Journal of Biomechanics, 32(2), pp 129-134 (1999), which is incorporated by reference herein in its entirety. Accordingly, based on the computer model and informed by the motion capture data, various activities of daily living may be simulated by the computer model.

[0157] The musculoskeletal model and tracked motion capture data may simulate “normal spine” activities of daily living. In some embodiments, the lumbar spine is discretized into segments (e.g., five segments, such as one per vertebra) connected by spherical joints. The spherical rotations may be constrained in the simulation to be equal across all joints (e.g., lateral bending between L1 and L2 is constrained to be equal to lateral bending between L2 and L3, L3 and L4, and so on). In this way, the lumbar spine motion may be homogeneous across vertebral joints.

[0158] In certain embodiments, a subsequent simulation may be run in which most joints of the musculoskeletal model are constrained to the motion obtained in the first simulation (i.e., the “normal spine” simulation) with the exception of some joints (e.g., the ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 hips), which are left unconstrained, and the lumbar spine joints, which are constrained to be within a threshold range (e.g., ±20°) in each degree of freedom (e.g., the overall lumbar twist calculated between S1 and L1 cannot go outside the threshold range). These boundary conditions imply that, when the spine hits a range threshold boundary, the rest of the joints need to compensate for the lack of mobility to achieve the same activity goal. For example, when simulating reaching to the ground on the side from a seated position, the hip needs to internally rotate more than in the “normal spine” case to compensate for the lack of lateral bending of the lumbar spine.

[0159] Based on the classification 415 of the spine (e.g., normal, fused, stiff, or hypermobile), the corresponding activity of daily living kinematics may be selected and applied to the virtual implanted model of the patient’s bones. For example, hip motions for non-normal spines (e.g., fused, stiff, or hypermobile) conditions may be derived by constraining the spinopelvic joint flexion within bounds and / or translating the extra flexion into the hips.

[0160] In some embodiments, analyzing 430 impingement in the at least one simulation includes transforming the simulation into an implant coordinate system and sweeping the simulated implant through a series of motions to detect when impingement (e.g., between the stem and cup or liner) occurs.

[0161] FIG.9A illustrates a modeled implant 900 coordinate systems in accordance with an embodiment. In certain embodiments, the coordinate system may be defined by an orientation of the acetabular cup 904. For example, the opening of the acetabular cup 904 may define a plane (e.g., including an x axis and a y axis). The origin may be defined as the center of the circle defined by the acetabular cup’s 904 intersection with the plane. The axes of the plane may be further defined based on the orientation of the stem 906 when the ball 902 is inserted in the acetabular cup 904. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0162] FIG.9B illustrates an example simulated sweep 914 in which the stem 906 rotates about an axis until impingement between the stem 906 and cup 904 or liner 908 occurs. FIG.9B further illustrates an example of impingement 910 with the liner 908 and impingement 912 with the cup 904. A series of sweeps 924 may be visualized in a range of motion profile 920 such as the example illustrated in FIG.9C. In some embodiments, the range of motion profile 920 can visualize each sweep 924 and the corresponding sweeps 924 that impinge 926.

[0163] In some embodiments, outputting 435 hip joint kinematic information based on the at least one simulation includes outputting a range of motion associated with one or more activities of daily living. In some embodiments, the outputted range of motion may be a range of motion associated with a specific activity of daily living. In some embodiments, the outputted range of motion may be a composite range of motion associated with a plurality of activities of daily living. For example, the plurality of activities of daily living may comprise all simulated activities of daily living. However, the plurality of activities of daily living may be limited based on any known information or data. For example, where a subset of the simulated activities of daily living are known or suspected to be pertinent (e.g., based on the regular activities of a particular patient), the composite range of motion may represent one or more pertinent activities of daily living. In some embodiments, a plurality of range of motions associated with distinct activities of daily living may be outputted separately. Accordingly, the outputted range of motion may represent the required range of motion for a post-operative patient.

[0164] In some embodiments, outputting 435 hip joint kinematic information based on the at least one simulation includes an impingement analysis as described herein. The impingement analysis may be provided across a range of motion. In further embodiments, the impingement analysis can be provided across one or more activities of daily living. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0165] In some embodiments, in addition to range of motion information, the hip joint kinematic information may include muscle and / or foot-ground forces and may predict joint contact forces. Joint contact forces may be used to estimate contact point location and / or other contact outputs, including, but not limited to, contact area, contact pressure, and component wear for the implant. In some embodiments, the outputted joint contact information may be used to inform implant placement as further described herein. For example, since total hip replacement edge loading (i.e., determined by contact locations near the edge of the acetabular cup component) may lead to implant failure. Accordingly, joint contact information may be pertinent to cup and stem placement to reduce the risk of edge loading.

[0166] In some embodiments, the joint kinematic information may be outputted 435 in a computer-readable format to a local device or a remote device. In some embodiments, the joint kinematic information may be outputted 435 to a computer-readable storage medium, a computer (e.g., a laptop computer or a desktop computer), a server, a database, a surgical system (e.g., CASS 100 of FIG.1), a surgical planning system, or any other device. In some embodiments, the joint kinematic information may be outputted 435 by any known transmission means including, but not limited to, a wired connection, a wireless connection (e.g., Bluetooth, WiFi, etc.), a local area network, the Internet, and / or a cellular network.

[0167] In some embodiments, outputting 435 the joint kinematic information may comprise displaying the joint kinematic information on a display device. For example, the joint kinematic information may be displayed on a display device such as a display of a personal computer, a mobile device, a tablet, the display 125 of the CASS 100 of FIG.1, and the like. Accordingly, a user may be able to view the joint kinematic information to evaluate a surgical plan, select an implant model and / or size, select and implant position and / or orientation, and the like. For example, the joint kinematic information may include one or ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 more calculated post-operative ranges of motion depicted as values and / or as graphics for comparison with the ranges of motion required for the activities of daily living. Accordingly, the joint kinematic information may inform selection of one or more parameters (e.g., implant model, size, position, and / or orientation). In some embodiments, the parameters may be selected via the input device (e.g., a touchscreen of a mobile device, tablet, or other device displaying the joint kinematic information) and recorded.

[0168] In some embodiments, the outputted joint kinematic information may be used to assess parameters of a surgical plan, such as a position and orientation of an implant (e.g., an acetabular cup). For example, the joint kinematic information may be outputted 435 to a surgical system (e.g., CASS 100 of FIG.1). The surgical system may use proposed implant information (e.g., a make, model, and size of a proposed implant) and anatomical information of the patient to assess one or more proposed placements of the implant. For example, the system may assess one or more implant placements, where each implant placement includes an implant position and an implant orientation (i.e., relative anterior or posterior orientation), to determine a post-operative range of motion of the hip joint associated with the implant placement in the manner disclosed herein and as understood by a person having an ordinary level of skill in the art. The post-operative range of motion associated with each implant placement may be compared to the outputted joint kinematic information to determine whether the required range of motion of the patient is permitted by the implant placement and / or how much of the required range of motion of the patient is permitted by the implant placement. Accordingly, the joint kinematic information may be used to optimize and / or select an implant placement of the implant based on the required range of motion. In some embodiments, a risk of impingement and / or capsule laxity for one or more activities of daily living may be quantified based on a comparison of the required ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 range of motion with a post-operative range of motion associated with a proposed implant placement.

[0169] In addition to range of motion, joint forces calculated for each range of motion position as described herein may also be outputted (e.g., displayed as a pressure map graphic with the range of motion or a separate graphic) and used to assess each implant placement. For example, unduly high joint forces may be detrimental to joint stability. Accordingly, joint forces beyond a predetermined threshold value may be negatively weighed in the assessment of each implant placement. In some embodiments, the location of the joint forces may be factored into the assessment. For example, unduly high joint forces near an edge or lip of the acetabular cup may pose a higher risk to joint stability. Accordingly, the magnitude and the location of joint forces may be used to determine a risk associated with the joint forces and accordingly weighed in the assessment of each implant placement.

[0170] In some embodiments, a level of stability, a risk of impingement, a risk of dislocation, and / or other metrics associated with the stability of the joint may be outputted for each implant placement. For example, a stability score, an impingement risk score, and / or a dislocation risk score may be outputted along with the range of motion and / or joint force information as described herein.

[0171] FIG.10 depicts an illustrative user interface 1000 for evaluating joint kinematic information in accordance with an embodiment. The user interface may include a classification 415 of the spinopelvic condition of a patient. The user interface may include selections and / or visualizations of parameters 1004 of the implant. Example parameters include implant type, liner options, ball size, neck length and stem type. In some embodiments, the user interface can include an option to compare one or more additional sets of implant parameters 1004. The evaluation, as described herein, for the one or more additional sets of implant parameters 1004 may be concurrently displayed or selectively ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 individually displayed. In certain embodiments, a recommendation for one or more of the parameters 1004 may be provided by the surgical system (e.g., CASS 100 of FIG.1) based on the joint kinematic information.

[0172] In certain embodiments, the user interface 1000 includes placement values 1008 of the implant. In further embodiments, the placement values include a cup inclination, a cup anteversion, and a stem anteversion. In some embodiments, the user interface can include an option to compare one or more additional sets of placement values 1008. In further embodiments, the user can compare one or more sets of implant parameters each associated with a unique set of placement values.

[0173] The placement values 1008 may be customizable by the user. Additionally or alternatively, the surgical system (e.g., CASS 100 of FIG.1) may provide optimized placement values 1008 based on the joint kinematic information. For example, the user interface may provide the user with an Autocenter toggle. When Autocenter is enabled, the surgical system may be configured to calculate cup angle recommendations. Calculating cup angle recommendations may include determining an optimal cup anteversion based on the stem anteversion selected by the user and / or pre-defining changes to cup inclination and anteversion based on the spinopelvic condition of the patient. An algorithm to calculate cup angle recommendations may be configured to center the activity of daily living lines 1016 within the range of motion profile 1014 and minimize impingement. In some embodiments, the algorithm can be used to optimize implant placement and minimize impingement during activities of daily living, given a set of constraints, which may be configurable by the user.

[0174] In certain embodiments, the user interface 1000 can include a visualization of the simulated anatomy and implant 1006 based on the implant parameters 1004 and placement values 1008. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0175] In some embodiments, the user interface 1000 can depict range of motion parameters for implant impingement analysis 1010. Each combination of implant parameters 1004 and placement values 1008 may have corresponding range of motion parameters. The range of motion parameters may be displayed in a range of motion profile 1014. The range of motion profile 1014 may be calculated over a plurality of simulations that find the maximum rotation of the stem before impingement in the plurality of different directions. Optimally, the plurality of simulations is sufficiently high (e.g., 18) such that the area within the range of motion profile 1014 approximately indicates the angles that can be reached by the stem without impingement with the cup or liner.

[0176] The activity of daily living motions 1016 may be displayed on top of the range of motion profile 1014 as lines that include the hip angles achieved throughout each activity of daily life motion. If the activity of daily living motion 1016 is entirely contained by the range of motion profile 1014, the activity may be completed without impingement. In contrast, impingement may occur if the activity of daily living motion 1016 intersects the range of motion profile 1014. Within the same diagram 1010, the minimum distance between the activity of daily living lines 1016 and the range of motion profile 1014 may be calculated.

[0177] In some embodiments, the user interface 1000 can depict an activity wheel 1012 that displays a metric relevant to impingement for different activities of daily life. The activity wheel 1012 may display the minimum distance 1020 to impingement for all, or a subset of, activities of daily living. Each activity of daily living line 1018 may be represented by an arc. If the arc touches the circle representative of the minimum distance 1020, an indication of impingement may be made. For example, the arc 1018, section of the activity wheel 1012, and / or an icon representing of the activity of daily living may change color if impingement is detected. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0178] FIG.11 depicts an illustrative user interface 1100 for evaluating impingement in accordance with an embodiment. As described herein, the system may require a patient’s CT scan to derive a three-dimensional model 1102 of the patient’s hip anatomy. The three-dimensional model 1102 may be used to template the patient’s hip (i.e., selecting and positioning implant components based on the anatomy). Additionally, the three- dimensional model 1102 may also be used for bone-on-bone impingement analysis.

[0179] In certain embodiments, each activity of daily living included in the system, or a subset thereof, may have an icon 1104 that can be interacted with (e.g., clicked, double clicked, moused over, etc.). As a result of an interaction, the icon 1104 may display a corresponding animation. In some embodiments, each icon 1104 is configured to communicate to the user if impingement occurs during the activity of daily living motion. For example, the icon or a corresponding border may be color coded based on the detection of impingement. In embodiments featuring a border, the missing portion of the border can indicate how much and when impingement occurs during the activity of daily living. In some embodiments, the status of the icons 1104 may update automatically as adjustments are made to the implant parameters 1004 and placement values 1008. In certain embodiments, the icons 1104 are organized in groups that indicate whether the activity of daily living is more prone to impingement on the anterior or posterior side.

[0180] The three-dimensional model 1102 of the anatomy and / or a model of the implant 1108 (e.g., the liner) may be configured to depict impingement areas 1106 / 1110. In some embodiments, when no activity of daily living is selected (e.g., through an icon 1104), a summary of areas 1106 / 1110 impinging during the included activities of daily living is displayed on the three-dimensional model with highlighted areas (e.g., through colorization or outlining). In further embodiments, impinging patches in the three-dimensional model may be color-coded and / or shaded with a color and / or intensity indicating a degree of penetration ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 between the two impinging objects (e.g., bone or implant). In further embodiments, bone-on- bone impingement areas 1106 are displayed on the three-dimensional model 1102, and implant-on-implant impingement areas 1110 are displayed on the implant model 1108. In some embodiments, interacting with an impingement area 1106 / 1110 can present the user with the activity of daily living in which the impingement occurs (e.g., highlighting the icon(s) 1104 and / or overlaying an identifier of the activity of daily living).

[0181] In certain embodiments, an alternative impingement diagram 1010 and activity wheel 1012 may be generated that illustrate bone-on-bone impingement. The range of motion profile may be a three-dimensional diagram (i.e., instead of a planar diagram). Distance to impingement may be similarly calculated and displayed in the activity wheel 1012. In some embodiments, distance to impingement in bone-on-bone impingement can be directly calculated as a three-dimensional distance between potentially impinging objects within the three-dimensional model. In further embodiments, the distance measured with length units can be visualized within the activity wheel 1012 without generating an Impingement diagram 1010.

[0182] In certain embodiments, the implant model 1108 can present an indicator 1112 of the jump distance (i.e., the distance the head needs to travel to dislocate) when the stem impinges in a location. The indicator 1112 may include a color-coded border to the implant model. A jump distance indicator 1112 may be useful when lipped liners are used and the lip orientation is planned to have a largest jump distance corresponding with impingement. By considering jump distance, the system and / or user may maximize joint stability when impingement cannot be avoided.

[0183] Additionally or alternatively to simulating activities of daily living motions, the user may also simulate and / or analyze preset motions. FIG.12 depicts an illustrative user interface 1200 that can be interacted with to visualize simple preset motions in one or two ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 directions. For example, preset motions may include external rotation or flexion to 90° followed by internal rotation. In some embodiments, the motion stops as soon as impingement is detected. As a result, a preset motion may be not fully predefined. The range of motion (e.g., measured in degrees) before impingement may be displayed within the icon itself. Similar to activities of daily living, the data provided may update in real-time when the user makes changes to the implant parameters 1004 and placement values 1008.

[0184] It should be understood that the presently disclosed method is advantageous over conventional methods because the outputted joint kinematic information carries a reduced risk of impingement based on an approximated required range of motion that accounts for the spinopelvic conditions of the patient. Furthermore, by conservatively assessing spinopelvic mobility, the outputted required range of motion may be greater than an actual required range of motion for the post-operative patient in many cases, thereby further reducing a risk of impingement.

[0185] In additional embodiments of the present subject matter, the method 400 may be implemented in a system configured to perform each of the described steps. For example, a system may comprise at least one processor and a computer-readable storage medium comprising instructions configured to, when executed, cause the at least one processor to obtain a computer model of the human anatomy, receive input related to a spinopelvic condition of the patient, classify the spinopelvic condition of the patient based on the input, condition the computer model based on the spinopelvic condition, perform at least one simulation of one or more activities of daily living with the computer model, and output hip joint kinematic information based on the at least one simulation as described herein. In some embodiments, the system may further comprise an input device configured to receive the input related to the spinopelvic condition of the patient as user input and transmit the user ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 input to the at least one processor. The input device may be implemented in any manner as would be apparent to a person having an ordinary level of skill in the art.

[0186] The devices, systems, and methods as described herein are not intended to be limited in terms of the particular embodiments described, which are intended only as illustrations of various features. Many modifications and variations to the devices, systems, and methods can be made without departing from their spirit and scope, as will be apparent to those skilled in the art.

[0187] While the devices, systems, and methods are generally described herein as focusing on the hip joints, it should be understood that the methods may be limited to one specific hip joint of interest, e.g., an operative hip joint for which a surgical procedure is being planned. It should also be understood that the devices, systems, and methods described herein may be adapted to assess required ranges of motion of additional joints (e.g., knee joints) that may be impacted.

[0188] In some embodiments, motion capture data may be collected from the patient in order to input patient-specific motion information for building and conditioning the computer model in a customized manner. In some embodiments, the patient may be instructed through a series of poses and assessed in an office, a clinic, a laboratory, or other setting with a motion capture system as described herein to collect motion capture data. In some embodiments, in addition to sitting and standing poses, additional poses may be assessed with the motion capture system in order to provide data pertinent to other activities of daily living. Accordingly, the additional data may be used to condition the computer model to categorize the patient with greater accuracy.

[0189] While the use of lateral x-rays is generally described, it should be understood that additional types of 2D or 3D images depicting the spinopelvic joint of a patient in the sagittal plane may be used, including but not limited to CT, MRI, and ultrasound imaging. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 Further, additional views of the spinopelvic joint (e.g., anterior, posterior, and / or oblique) may be incorporated to provide additional information, such as mobility in the transverse plane and / or frontal plane. In some embodiments, the spinopelvic characterization (e.g., sacral slope angles and / or spinopelvic classification) may be generated or determined without the use of imaging. For example, an adequately sensitive motion capture system may be configured to determine sacral slope angles at one or more poses of the patient. In some embodiments, the motion capture system may be a camera-based motion capture system as described. In some embodiments, the motion capture system may additionally or alternatively use inertial or electromagnetic sensors to capture motion with adequate sensitivity to determine sacral slopes. Accordingly, the resulting characterization may be provided as input as described herein to condition the computer model.

[0190] While user input is generally described herein, it should be understood that the process may be further automated by excluding user input. For example, in some embodiments, a system as described herein may retrieve images of the spinopelvic joint of the patient and / or additional information associated with the patient from a variety of sources, e.g., a remote device or a local storage medium. In some embodiments, determining sacral slopes from images may be semi-automated (e.g., using identification of anatomical landmarks by a user to determine the sacral slopes) or entirely automated. Data Processing Systems for Implementing Embodiments Herein

[0191] FIG.13 illustrates a block diagram of an exemplary data processing system 1000 in which embodiments are implemented. The data processing system 1300 is an example of a computer, such as a server or client, in which computer usable code or instructions implementing the process for illustrative embodiments of the present invention are located. In some embodiments, the data processing system 1300 may be a server computing device. For example, the data processing system 1300 may be implemented in a ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 server or another similar computing device operably connected to a surgical system 100 as described above. The data processing system 1300 may be configured to, for example, transmit and receive information related to a patient and / or a related surgical plan with the surgical system 100.

[0192] In the depicted example, the data processing system 1300 may employ a hub architecture including a north bridge and memory controller hub (NB / MCH) 1301 and south bridge and input / output (I / O) controller hub (SB / ICH) 1302. A processing unit 1303, a main memory 1304, and a graphics processor 1305 may be connected to the NB / MCH 1301. The graphics processor 1305 may be connected to the NB / MCH 1301 through, for example, an accelerated graphics port (AGP).

[0193] In the depicted example, a network adapter 1306 connects to the SB / ICH 1302. An audio adapter 1307, a keyboard and mouse adapter 1308, a modem 1309, a read only memory (ROM) 1310, a hard disk drive (HDD) 1311, an optical drive (e.g., CD or DVD) 1312, a universal serial bus (USB) ports and other communication ports 1313, and PCI / PCIe devices 1314 may connect to the SB / ICH 1302 through a bus system 1316. The PCI / PCIe devices 1314 may include Ethernet adapters, add-in cards, and / or PC cards for notebook computers. The ROM 1310 may be, for example, a flash basic input / output system (BIOS). The HDD 1311 and the optical drive 1312 may use an integrated drive electronics (IDE) or serial advanced technology attachment (SATA) interface. A super I / O (SIO) device 1315 may be connected to the SB / ICH 1302.

[0194] An operating system may run on the processing unit 1303. The operating system may coordinate and provide control of various components within the data processing system 1300. As a client, the operating system may be a commercially available operating system. An object-oriented programming system, such as the JavaTMprogramming system, may run in conjunction with the operating system and provide calls to the operating system ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 from the object-oriented programs or applications executing on the data processing system 1300. As a server, the data processing system 1300 may be an IBM® eServerTMSystem®running the Advanced Interactive Executive operating system or the Linux operating system. The data processing system 1300 may be a symmetric multiprocessor (SMP) system that includes a plurality of processors in the processing unit 1303. Alternatively, a single processor system may be employed.

[0195] Instructions for the operating system, the object-oriented programming system, and applications or programs are located on storage devices, such as the HDD 1311, and are loaded into the main memory 1304 for execution by the processing unit 1303. The processes for embodiments described herein may be performed by the processing unit 1303 using computer usable program code, which can be located in a memory such as, for example, main memory 1304, ROM 1310, or in one or more peripheral devices.

[0196] A bus system 1316 may comprise one or more busses. The bus system 1316 may be implemented using any type of communication fabric or architecture that provides for a transfer of data between different components or devices attached to the fabric or architecture. A communication unit such as the modem 1309 or the network adapter 1306 may include one or more devices that can be used to transmit and receive data.

[0197] Those of ordinary skill in the art will appreciate that the hardware depicted in FIG. 10 may vary depending on the implementation. Other internal hardware or peripheral devices, such as flash memory, equivalent non-volatile memory, or optical disk drives may be used in addition to or in place of the hardware depicted. Moreover, the data processing system 1300 can take the form of any of a number of different data processing systems, including but not limited to, client computing devices, server computing devices, tablet computers, laptop computers, telephone or other communication devices, personal digital assistants, and the like. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 Essentially, data processing system 1300 can be any known or later developed data processing system without architectural limitation.

[0198] While various illustrative embodiments incorporating the principles of the present teachings have been disclosed, the present teachings are not limited to the disclosed embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of the present teachings and use its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which these teachings pertain.

[0199] In the above detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the present disclosure are not meant to be limiting. Other embodiments may be used, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that various features of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.

[0200] The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various features. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202

[0201] With respect to the use of substantially any plural and / or singular terms herein, those having skill in the art can translate from the plural to the singular and / or from the singular to the plural as is appropriate to the context and / or application. The various singular / plural permutations may be expressly set forth herein for sake of clarity.

[0202] It will be understood by those within the art that, in general, terms used herein are generally intended as “open” terms (for example, the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” et cetera). While various compositions, methods, and devices are described in terms of “comprising” various components or steps (interpreted as meaning “including, but not limited to”), the compositions, methods, and devices also can “consist essentially of” or “consist of” the various components and steps, and such terminology should be interpreted as defining essentially closed-member groups.

[0203] In addition, even if a specific number is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (for example, the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, et cetera” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (for example, “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, et cetera). In those instances where a convention analogous to “at least one of A, B, or C, et cetera” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (for example, “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 alone, A and B together, A and C together, B and C together, and / or A, B, and C together, et cetera). It will be further understood by those within the art that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the description, sample embodiments, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

[0204] In addition, where features of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0205] As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, et cetera. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, et cetera. As will also be understood by one skilled in the art all language such as “up to,” “at least,” and the like include the number recited and refer to ranges that can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 cells refers to groups having 1, 2, or 3 cells. Similarly, a group having 1-5 cells refers to groups having 1, 2, 3, 4, or 5 cells, and so forth.

[0206] The term “about,” as used herein, refers to variations in a numerical quantity that can occur, for example, through measuring or handling procedures in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of compositions or reagents; and the like. Typically, the term “about” as used herein ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 means greater or lesser than the value or range of values stated by 1 / 10 of the stated values, e.g., ±10%. The term “about” also refers to variations that would be recognized by one skilled in the art as being equivalent so long as such variations do not encompass known values practiced by the prior art. Each value or range of values preceded by the term “about” is also intended to encompass the embodiment of the stated absolute value or range of values. Whether or not modified by the term “about,” quantitative values recited in the present disclosure include equivalents to the recited values, e.g., variations in the numerical quantity of such values that can occur, but would be recognized to be equivalents by a person skilled in the art.

[0207] Various of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments. ACTIVE\1605978092.2

Claims

Attorney Docket No. PT-6083-WO-PCT / D031202 CLAIMS What is claimed is:

1. A computer-implemented method comprising: receiving, by one or more processors, a three-dimensional model of a human anatomy comprising a spinopelvic joint; receiving, by the one or more processors, an input related to a spinopelvic condition of a patient; modifying, by the one or more processors, the three-dimensional model based on the input related to the spinopelvic condition of the patient and a placement of an implant; performing, by the one or more processors, at least one simulation of one or more activities with the modified three-dimensional model; and displaying, by the one or more processors, an impingement analysis based on the at least one simulation on a display device.

2. The computer-implemented method of claim 1, further comprising: determining, by the one or more processors, at least one of a sacral slope or a lumbar lordosis of the patient based on the input; and classifying, by the one or more processors, the spinopelvic condition of the patient based on at least one of the sacral slope or the lumbar lordosis in a plurality of positions; wherein modifying the three-dimensional model is further based on the spinopelvic condition.

3. The computer-implemented method of claim 1, wherein the three-dimensional model of the human anatomy comprises a plurality of segments and a plurality of joints, wherein the plurality of segments are interconnected by the plurality of joints. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 4. The computer-implemented method of claim 2, wherein classifying the spinopelvic condition of the patient further comprises classifying, based on a combination of a seated sacral slope and a standing sacral slope, a spinopelvic balance condition of the patient.

5. The computer-implemented method of claim 2, wherein classifying the spinopelvic condition of the patient further comprises classifying, based on a combination of a standing lumbar lordosis and a flex-seated lumbar lordosis, a spinopelvic balance condition of the patient.

6. The computer-implemented method of claim 2, wherein classifying the spinopelvic condition of the patient further comprises classifying, based on a combination of a standing lumbar lordosis and a relaxed-seated lumbar lordosis, a spinopelvic balance condition of the patient.

7. The computer-implemented method of claim 1, wherein classifying the spinopelvic condition of the patient further comprises classifying a spinopelvic mobility condition of the patient.

8. The computer-implemented method of claim 7, wherein the spinopelvic mobility condition of the patient is selected from the group consisting of fused, stiff, hypermobile, and normal.

9. The computer-implemented method of claim 2, wherein the input comprises two or more 2D images of the spinopelvic joint of the patient. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 10. The computer-implemented method of claim 9, wherein determining at least one of the sacral slope or the lumbar lordosis of the patient comprises: identifying a plurality of landmarks in the two or more 2D images; and calculating at least one of a sacral slope or a lumbar lordosis of the patient based on the plurality of landmarks.

11. The computer-implemented method of claim 1, wherein performing at the least one simulation of the one or more activities with the modified three-dimensional model comprises transforming the simulation into a coordinate system based on the implant placement.

12. The computer-implemented method of claim 11, wherein performing the at least one simulation of the one or more activities with the modified three-dimensional model further comprises simulating a rotation of a stem of the implant about an axis until impingement between the stem and a cup or liner of the implant occurs.

13. The computer-implemented method of claim 12, further comprising: simulating a plurality of rotations of the stem; and generating a range of motion profile for the plurality of rotations, wherein the range of motion profile indicates angles that can be reached by the stem without impingement with respect to the cup or liner.

14. The computer-implemented method of claim 12, wherein displaying the impingement analysis comprises visualizing a graphical representation of a minimum distance to impingement in reference to each of the one or more activities. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 15. The computer-implemented method of claim 1, wherein displaying the impingement analysis comprises: displaying the modified three-dimensional model; determining at least one area of bone-on-bone impingement based on the at least one simulation; and highlighting the at least one area of bone-on-bone impingement on the modified three- dimensional model.

16. The computer-implemented method of claim 1, wherein displaying the impingement analysis comprises: displaying the modified three-dimensional model; determining at least one area of bone-on-implant impingement based on the at least one simulation; and highlighting the at least one area of bone-on-implant impingement on the modified three-dimensional model.

17. The computer-implemented method of claim 1, wherein displaying the impingement analysis comprises: receiving a three-dimensional model of the implant; displaying the three-dimensional model of the implant; determining at least one area of implant-on-implant impingement based on the at least one simulation; and highlighting the implant-on-implant of impingement on the three-dimensional model of the implant. ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 18. The computer-implemented method of claim 1, further comprising generating an optimal placement of the implant based on the at least one simulation of one or more activities with the modified three-dimensional model.

19. The computer-implemented method of claim 18, wherein generating an optimal placement of the implant comprises: determining a jump distance for the at least one simulation of one or more activities; and selecting the optimal placement to maximize the jump distance.

20. A system for impingement analysis, the system comprising: an input device; a display device; at least one processor; and a non-transitory, computer-readable medium comprising instructions that, when executed, cause the at least one processor to: receive a three-dimensional model of a human anatomy; receive an input related to a spinopelvic condition of a patient; determine at least one of a sacral slope or a lumbar lordosis of the patient based on the input; classify the spinopelvic condition of the patient based on at least one of the sacral slope or the lumbar lordosis in a plurality of positions; modify the three-dimensional model based on the spinopelvic condition and a placement of an implant; ACTIVE\1605978092.2Attorney Docket No. PT-6083-WO-PCT / D031202 perform at least one simulation of one or more activities with the modified three-dimensional model; and display an impingement analysis on a display device based on the at least one simulation. ACTIVE\1605978092.2

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