Systems and methods for planning and assisting orthopedic surgical procedures

Abstract

A system and method for planning and assisting an orthopaedic surgical procedure includes a computer system and a robotic surgical device. The computer system receives a plurality of surgeon preferences including target values ​​and boundary values ​​for surgical parameters of the orthopaedic surgical procedure. The surgeon uses the computer system to perform bone alignment and leg alignment registration for the patient's anatomy. The computer system determines a surgical plan for the orthopaedic surgical procedure based on the surgeon's preferences, the bone alignment, and the leg alignment registration. The surgical plan includes planned values ​​associated with the surgical parameters that are within the boundary values ​​of the surgeon's preferences. Determining the surgical plan may include automatically adjusting tibial coronal alignment, femoral coronal alignment, femoral flexion, femoral rotation, distal femur resection height, proximal tibial resection height, and / or distal femur resection height. The computer system may control the robotic surgical device according to the surgical plan.

Description

[Technical Field]

[0001] (Incorporated by reference) This application claims priority to U.S. Non-Provisional Patent Application No. 18 / 091,486, filed December 30, 2022, which is incorporated herein by reference in its entirety.

[0002] (Technical Field 18 / 091486) The present disclosure relates generally to orthopaedic surgical tools and systems, and more particularly to systems and methods for automatically planning surgical parameters for use during orthopaedic surgical procedures. [Background technology]

[0003] Joint arthroplasty is a well-known surgical procedure in which a diseased and / or damaged natural joint is replaced with an artificial joint, which may include one or more orthopedic implants. For example, in a knee replacement surgery, a patient's natural knee joint is partially or totally replaced with an artificial knee joint. A typical knee prosthesis includes a tibial tray, a femoral component, and a polymer insert or bearing positioned between the tibial tray and the femoral component.

[0004] To facilitate replacing a natural joint with a prosthetic joint, an orthopaedic surgeon may use a variety of orthopaedic surgical instruments, such as, for example, surgical saws, cutting guides, reamers, broaches, drill guides, drills, positioners, insertion tools, and / or other surgical instruments. For example, a surgeon may prepare a patient's tibia to receive a tibial tray by resecting the proximal femur with a surgical saw, and a surgeon may prepare a patient's femur to receive a femoral component by performing multiple resections of the distal femur with a surgical saw. A surgeon may use manual instruments, such as cutting blocks or other cutting guides, to perform various resections in an orthopaedic surgical procedure. Alternatively, or in addition, a surgeon may use a computer-assisted surgical navigation system, such as a robotic-assisted surgical system, to perform various resections in an orthopaedic surgical procedure. Summary of the Invention [Means for solving the problem]

[0005] According to one aspect, a method for creating a surgical plan for an orthopaedic surgical procedure may include receiving, by a computer system, a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of the orthopaedic surgical procedure. The method may further include performing, using the computer system, a bony alignment of the patient's bony anatomy. The method may also include performing, using the computer system, a leg alignment registration of the patient. Performing the leg alignment registration may include measuring a flexion gap of the patient's knee joint and measuring an extension gap of the knee joint. The method may additionally include determining, by the computer system, a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the bony alignment, and the leg alignment registration. The surgical plan may include planned values ​​associated with surgical parameters of the orthopaedic surgical procedure, the planned values ​​may be within one or more boundary values ​​associated with the surgical parameters.

[0006] In some embodiments, the method may further include presenting, by the computer system, the surgical plan to a user and receiving, by the computer system, modifications to the surgical plan in response to presenting the surgical plan. The modifications may include updated boundary values ​​associated with the surgical parameters. The method may also include determining, by the computer system, an updated surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, bone alignment, leg alignment, and the updated boundary values, wherein the updated boundary values ​​override at least one of the plurality of surgeon preferences.

[0007] In some embodiments, determining a surgical plan for the orthopaedic surgical procedure may include automatically adjusting tibial coronal alignment, automatically adjusting femoral coronal alignment in response to automatically adjusting the tibial coronal alignment, automatically adjusting femoral flexion in response to automatically adjusting femoral coronal alignment, automatically adjusting femoral rotation in response to automatically adjusting femoral flexion, and automatically adjusting a distal femoral condyle resection height in response to automatically adjusting femoral rotation.

[0008] In some embodiments, automatically adjusting the tibial coronal alignment may include determining an initial proximal tibial resection height based on surgeon preference and an estimate of cartilage loss, and iteratively decreasing the proximal tibial resection height such that the coronal angle of the patient's tibia falls within the surgeon's preferred tibial varus / valgus boundaries while the proximal tibial resection height falls within the surgeon's preferred minimum proximal tibial resection height boundaries.

[0009] In some embodiments, automatically adjusting the femoral coronal plane alignment may include determining an initial distal femoral condyle resection height based on a surgeon's preference and an estimate of cartilage loss, and iteratively increasing the distal femoral condyle resection height while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundaries and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundaries until the medial extension gap is equal to the lateral extension gap.

[0010] In some embodiments, automatically adjusting the femoral flexion can include iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundary until the total flexion gap is equal to the ideal flexion gap. The total flexion gap can include the sum of the lateral flexion gap and the medial flexion gap, and the ideal flexion gap can include the sum of the natural joint laxity in flexion and the default component height. In response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary, automatically adjusting the femoral flexion can also include iteratively adjusting the femoral component anterior / posterior shift while the posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary until the total flexion gap is equal to the ideal flexion gap.

[0011] In some embodiments, automatically adjusting the femoral flexion may further include determining a difference between the total flexion gap and the ideal flexion gap in response to the posterior femoral condyle resection height reaching a posterior femoral condyle resection height boundary. Automatically adjusting the femoral flexion may also include determining whether the difference is greater than a predetermined length. The predetermined length may be associated with a femoral component size difference. In response to determining that the difference is greater than the predetermined length, automatically adjusting the femoral flexion may further include prompting a change to the femoral component size. In response to determining that the difference is not greater than the predetermined length, automatically adjusting the femoral flexion while the proximal tibia resection height is within the proximal tibia resection height boundary may also include iteratively adjusting the proximal tibia resection height until the difference reaches the predetermined length. In response to changing the femoral component size or iteratively adjusting the proximal tibia resection height, automatically adjusting the femoral flexion may further include resetting the femoral component flexion / extension angle and the femoral component anterior / posterior shift.

[0012] In some embodiments, when the total flexion gap is greater than the ideal flexion gap, iteratively adjusting the femoral component flexion / extension angle may include increasing the femoral component flexion angle, iteratively adjusting the femoral component anterior / posterior shift may include increasing the femoral component posteriorization, prompting a change to the femoral component size may include prompting an increase in the femoral component size, and iteratively adjusting the proximal tibial resection height may include decreasing the proximal tibial resection height.

[0013] In some embodiments, when the total flexion gap is less than the ideal flexion gap, iteratively adjusting the femoral component flexion / extension angle may include decreasing the femoral component flexion angle, iteratively adjusting the femoral component anterior / posterior shift may include increasing the anteriorization of the femoral component, prompting a change to the femoral component size may include prompting a decrease in the femoral component size, and iteratively adjusting the proximal tibial resection height may include increasing the proximal tibial resection height.

[0014] In some embodiments, automatically adjusting the femoral rotation may include iteratively rotating the femoral component while the posterior femoral condyle resection height is within the posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to the target medial and lateral flexion gaps, respectively.

[0015] In some embodiments, automatically adjusting the distal femoral condyle resection height may include iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within a distal femoral condyle resection height boundary until the total extension gap is equal to the total flexion gap.

[0016] According to another aspect, an orthopaedic surgical planning system may comprise a computer system configured to: receive a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of an orthopaedic surgical procedure; obtain alignment data for a patient's knee joint, the alignment data defining a knee flexion gap and a knee extension gap; and determine a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences and the alignment data, the surgical plan including planned values ​​associated with surgical parameters of the orthopaedic surgical procedure, the planned values ​​being within one or more boundary values ​​associated with the surgical parameters.

[0017] In some embodiments, the orthopaedic surgical planning system may further comprise a registration tool configured to be positioned relative to a plurality of anatomical landmarks of the patient while being viewed by the computer system to obtain registration data. The orthopaedic surgical planning system may also comprise a robotic surgical device configured to position a cutting tool to resect bone of the patient to achieve planned values ​​of the surgical plan.

[0018] In some embodiments, the computer system may be further configured to present the surgical plan to a user; receive modifications to the surgical plan in response to presenting the surgical plan, the modifications including updated boundary values ​​associated with the surgical parameters; and determine an updated surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the alignment data, and the updated boundary values, the updated boundary values ​​overriding at least one of the plurality of surgeon preferences.

[0019] In some embodiments, the computer system may be configured to determine a surgical plan for the orthopaedic surgical procedure by automatically adjusting tibial coronal alignment, automatically adjusting femoral coronal alignment in response to automatically adjusting the tibial coronal alignment, automatically adjusting femoral flexion in response to automatically adjusting femoral coronal alignment, automatically adjusting femoral rotation in response to automatically adjusting femoral flexion, and automatically adjusting a distal femoral condyle resection height in response to automatically adjusting femoral rotation.

[0020] In some embodiments, the computer system may be configured to automatically adjust the tibial coronal alignment by determining an initial proximal tibial resection height based on the surgeon's preference and an estimate of cartilage loss, and iteratively decreasing the proximal tibial resection height until the coronal angle of the patient's tibia falls within the surgeon's preferred tibial varus / valgus boundaries while the proximal tibial resection height falls within the surgeon's preferred minimum proximal tibial resection height boundaries.

[0021] In some embodiments, the computer system can be configured to automatically adjust the femoral coronal alignment by determining an initial distal femoral condyle resection height based on the surgeon's preference and an estimate of cartilage loss, and iteratively increasing the distal femoral condyle resection height while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundaries and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundaries, until the medial extension gap equals the lateral extension gap.

[0022] In some embodiments, the computer system may be configured to automatically adjust the femoral flexion by iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundary until the total flexion gap is equal to the ideal flexion gap. The total flexion gap may comprise the sum of the lateral flexion gap and the medial flexion gap, and the ideal flexion gap may comprise the sum of the natural joint laxity in flexion and the default component height. The computer system may be further configured to automatically adjust the femoral flexion by iteratively adjusting the femoral component anterior / posterior shift in response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary until the total flexion gap is equal to the ideal flexion gap while the posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary.

[0023] In some embodiments, the computer system can be configured to automatically adjust the femoral rotation by iteratively rotating the femoral component while the posterior femoral condyle resection height is within the posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to the target medial and lateral flexion gaps, respectively.

[0024] In some embodiments, the computer system can be configured to automatically adjust the distal femoral condyle resection height by iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within the distal femoral condyle resection height boundary until the total extension gap equals the total flexion gap. [Brief explanation of the drawings]

[0025] The concepts described herein are illustrated by way of example, and not by way of limitation, in the accompanying drawings. For simplicity and clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. Where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding or analogous elements. The detailed description makes specific reference to the following drawings: [Figure 1] 1 is a schematic diagram of a system for planning and assisting orthopaedic surgical procedures. [Figure 2] FIG. 2 is a simplified block diagram of an environment that may be established by the surgical planning and assistance devices of the system of FIG. 1. [Figure 3] FIG. 3 is a simplified flow diagram of a method for an orthopedic surgical procedure including automated surgical planning that may be performed by the surgical planning and assistance device of FIGS. 1 and 2. [Figure 4] 3 is a schematic diagram illustrating surgeon preferences that may be collected and otherwise processed by the surgical planning and assistance device of FIGS. 1 and 2. FIG. [Figure 5] FIG. 3 is a simplified flow diagram of a method for leg alignment registration that may be performed by the surgical planning and assistance device of FIGS. 1 and 2. [Figure 6] FIG. 3 is a simplified flow diagram of a method for automated surgical planning that may be performed by the surgical planning and assistance device of FIGS. 1 and 2. [Figure 7] FIG. 3 is a simplified flow diagram of a method for automatically adjusting tibial coronal alignment that may be performed by the surgical planning and assist device of FIGS. 1 and 2. [Figure 8] FIG. 3 is a simplified flow diagram of a method for automatically adjusting femoral coronal alignment that may be performed by the surgical planning and assistance device of FIGS. 1 and 2. [Figure 9] FIG. 3 is a simplified flow diagram of a method for automatically adjusting femoral flexion that may be performed by the surgical planning and assist device of FIGS. 1 and 2. [Figure 10]FIG. 3 is a simplified flow diagram of a method for automatically adjusting femoral flexion and posteriorization that may be performed by the surgical planning and assist device of FIGS. 1 and 2. [Figure 11] FIG. 3 is a simplified flow diagram of a method for automatically adjusting femoral flexion and anteriorization that may be performed by the surgical planning and assist device of FIGS. 1 and 2. [Figure 12] FIG. 3 is a simplified flow diagram of a method for automatically adjusting femoral rotation that may be performed by the surgical planning and assist device of FIGS. 1 and 2. [Figure 13] FIG. 3 is a simplified flow diagram of a method for automatically adjusting medial and lateral distal femoral condyle resection heights that may be performed by the surgical planning and assistance device of FIGS. 1 and 2. [Figure 14] FIG. 3 is a schematic diagram of one illustrative embodiment of a graphical user interface that may be provided by the surgical planning and assistance device of FIGS. 1 and 2. DETAILED DESCRIPTION OF THE INVENTION

[0026] While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that it is not the intention of this disclosure to limit the concepts of the present disclosure to the particular forms disclosed, but rather the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure and the appended claims.

[0027] Terms denoting anatomical references, such as anterior, posterior, medial, lateral, superior, inferior, etc., may be used throughout this specification with respect to the orthopedic implants or prostheses and surgical instruments described herein, as well as with reference to a patient's natural anatomy. Such terms have well-understood meanings both in the study of anatomy and in the field of orthopedic surgery. Use of such anatomical reference terms in the written description and claims is intended to be consistent with their well-understood meanings, unless otherwise specified.

[0028] References herein to "one embodiment," "embodiment," "exemplary embodiment," etc. indicate that the embodiment being described may include a particular element, structure, or feature, but not all embodiments necessarily include that particular element, structure, or feature. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular element, structure, or feature is described in connection with one embodiment, it is believed to be within the knowledge of one of ordinary skill in the art to implement such element, structure, or feature in connection with other embodiments, whether or not explicitly described. Additionally, it should be understood that items listed in the form "at least one of A, B, and C" can mean (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C). Similarly, items listed in the form "at least one of A, B, or C" can mean (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C).

[0029] The disclosed embodiments may be implemented as hardware, firmware, software, or any combination thereof, as the case may be. The disclosed embodiments may also be implemented as instructions carried by or stored on a transient or non-transitory machine-readable (e.g., computer-readable) storage medium that may be read and executed by one or more processors. A machine-readable storage medium may be embodied as any storage device, mechanism, or other physical structure for storing or transmitting information in a form readable by a machine (e.g., a volatile or non-volatile memory, a media disk, or other media device).

[0030] In the figures, some structural or method elements may be shown in a specific arrangement and / or order. However, it should be recognized that such specific arrangement and / or order may not be required. Rather, in some embodiments, such elements may be arranged in a different manner and / or order than that shown in the illustrative figures. Additionally, the inclusion of a structural or method element in a particular figure does not imply that such element is required in all embodiments, and in some embodiments, it may not be included or may be combined with other elements.

[0031] Referring now to FIG. 1 , surgical system 100 is used during an orthopedic surgical procedure, illustratively a total knee arthroplasty (TKA) procedure. During the procedure, an orthopedic surgeon uses system 100 to align the patient's anatomy. The surgeon or other user uses surgical planning and assistance device 102 to automatically create a surgical plan based on one or more surgeon preferences (which may be created in advance) and alignment data. The surgeon may adjust one or more parameters of the surgical plan, and surgical planning and assistance device 102 automatically adjusts the remaining parameters. A robotic surgical device 104 may be controlled based on the surgical plan during the operation of the surgical procedure, for example, by robotically constraining a surgical saw 106 to one or more resection planes defined by the surgical plan.

[0032] Thus, system 100 provides improved automated surgical planning. System 100 may determine a complete surgical plan more quickly and / or with less user intervention compared to systems that require the surgeon to directly position or otherwise adjust the resection plane. Thus, system 100 may provide faster surgical planning and / or faster iteration times for surgical planning compared to typical surgical planning systems.

[0033] As shown in FIG. 1 , system 100 includes a surgical planning and assistance device 102 and a robotic surgical device 104, as well as multiple alignment targets 108. Surgical planning and assistance device 102 may be embodied as any type of computer system capable of performing the functions described herein. For example, surgical planning and assistance device 102 may be embodied as, without limitation, a workstation, a desktop computer, a laptop computer, a dedicated computing device, a server, a rack-mounted server, a blade server, a network appliance, a web appliance, a tablet computer, a smartphone, a consumer electronics device, a distributed computing system, a multiprocessor system, and / or any other computing device capable of performing the functions described herein. Additionally, while surgical planning and assistance device 102 is illustrated in FIG. 1 as being embodied as a single computer, it should be understood that surgical planning and assistance device 102 may be embodied as multiple devices cooperating with each other to facilitate the functions described below. For example, in some embodiments, system 100 may include a base station and a satellite station, or other combination of computing devices. Additionally or alternatively, in some embodiments, the surgical planning and assistance device 102 may be embodied as a "virtual server" formed from multiple computer systems distributed across a network and running in a public or private cloud.

[0034] 1 , the illustrative surgical planning and assistance device 102 includes a processor 120, an I / O subsystem 122, a memory 124, a data storage device 126, and a communications subsystem 128. Of course, the surgical planning and assistance device 102, in other embodiments, may include other or additional components, such as those typically found in a computer (e.g., various input / output devices). Additionally, in some embodiments, one or more of the illustrative components may be incorporated into or form part of another component. For example, the memory 124, or a portion thereof, may be incorporated into the processor 120 in some embodiments.

[0035] The processor 120 may be embodied as any type of processor or controller capable of performing the functions described herein. For example, the processor may be embodied as a single or multi-core processor, digital signal processor, microcontroller, or other processor or processing / control circuitry. Similarly, the memory 124 may be embodied as any type of volatile or non-volatile memory or data storage capable of performing the functions described herein. During operation, the memory 124 may store various data and software, such as an operating system, applications, programs, libraries, and drivers, used during operation of the surgical planning and assistance device 102. The memory 124 is communicatively coupled to the processor 120 via an I / O subsystem 122, which may be embodied as circuits and / or components for facilitating input / output operations by the processor 120, the memory 124, and other components of the surgical planning and assistance device 102. For example, the I / O subsystem 122 may be embodied as or may otherwise include a memory controller hub, an input / output control hub, firmware devices, communication links (i.e., point-to-point links, bus links, wires, cables, light guides, printed circuit board traces, etc.), and / or other components and subsystems for facilitating input / output operations. In some embodiments, the I / O subsystem 122 may form part of a system-on-a-chip (SoC) and may be incorporated into a single integrated circuit chip along with the processor 120, memory 124, and other components of the surgical planning and assistance device 102.

[0036] The data storage device 126 may be embodied as any type of device or devices configured for short-term or long-term storage of data, such as, for example, memory devices and circuits, memory cards, hard disk drives, solid-state drives, or other data storage devices. The communications subsystem 128 of the surgical planning and assistance device 102 may be embodied as any communications circuitry, device, or collection thereof capable of enabling communications between the surgical planning and assistance device 102 and a remote device. The communications subsystem 128 may be configured to perform such communications using any one or more communications technologies (e.g., wired or wireless communications) and associated protocols (e.g., Ethernet, Bluetooth, Wi-Fi, WiMAX, etc.).

[0037] 1 , the surgical planning and assistance device 102 includes a display 130. The display 130 may be embodied as any type of display capable of displaying digital images or other information, such as a liquid crystal display (LCD), a light emitting diode (LED), a plasma display, a cathode ray tube (CRT), or other type of display device. In some embodiments, the display 130 may be coupled to a touch screen that allows for user interaction with the surgical planning and assistance device 102.

[0038] The surgical planning and assistance device 102 further includes one or more cameras 132. Each of the cameras 132 may be embodied as a digital camera or other digital imaging device coupled to the surgical planning and assistance device 102. Each camera 132 includes an electronic image sensor such as an active-pixel sensor (APS), e.g., a complementary metal-oxide-semiconductor (CMOS) sensor, or a charge-coupled device (CCD). In an illustrative embodiment, multiple cameras 132 are arranged in an array, so that the distance to an object imaged by the camera 132 can be determined.

[0039] The robotic surgical device 104 may be embodied as any type of robot capable of performing the functions described herein. Illustratively, the robotic surgical device 104 is embodied as a robotic arm that may be attached to an operating table or otherwise positioned near a patient during an orthopedic surgical procedure. The robotic surgical device 104 includes a surgical tool 106, illustratively embodied as a surgical saw 106. In use, the robotic surgical device 104 supports the surgical saw 106 and, as described further below, may constrain movement of the surgical saw 106 within a resection plane specified in a surgical plan. A surgeon may activate and perform resections using the surgical saw 106 while the robotic surgical device 104 constrains movement of the surgical saw 106 to the resection plane. While illustrated with a surgical saw 106, it should be understood that in other embodiments, the robotic surgical device 104 may include or be used with one or more other surgical instruments, such as, for example, a surgical burr, an impactor, a reamer, and other powered surgical tools. The robotic surgical device 104 may illustratively be embodied as the VELYS™ Robotic-Assisted Solution, commercially available from DePuy Synthes Products, Inc. of Warsaw, Indiana.

[0040] The surgical planning and assistance devices 102 and the robotic surgical devices 104 may be configured to send and receive data with each other and / or with other devices in the system 100 via a network 114. The network 114 may be embodied as any number of various wired and / or wireless networks. For example, the network 114 may be embodied as or otherwise include a wired or wireless local area network (LAN), a wired or wireless wide area network (WAN), a mobile network, and / or a publicly accessible global network such as the Internet. Accordingly, the network 114 may include any number of additional devices, such as additional computers, routers, stations, and switches, to facilitate communication between the devices in the system 100.

[0041] As shown in FIG. 1 , the system 100 further includes several alignment tools 108. As described further below, in use, the surgical planning and assistance device 102 may use an array of cameras 132 to track the position of the alignment tools 108 in space. For example, each alignment tool 108 may include several hydrophobic light reflectors arranged in a predetermined pattern visible to the camera 132. Illustratively, the alignment tools 108 include multiple arrays 110 each configured to be fixed to one of the patient's bones, the robotic surgical device 104, or the surgical tool 106. Illustratively, the alignment tool 108 also includes a pointer 112 configured to be temporarily positioned by the surgeon relative to the patient's anatomical landmarks (e.g., with an end of the pointer 112 in contact with those anatomical landmarks) while the pointer 112 is observed by the camera 132. Thus, the alignment tool 108 may be used for aligning and tracking the patient's bony anatomical structures during an orthopedic surgical procedure.

[0042] 2 , in an illustrative embodiment, the surgical planning and assistance device 102 establishes an environment 200 during operation. The illustrative environment 200 includes a display manager 202, a preference manager 204, an alignment manager 206, and a surgical planner 208. The various components of the environment 200 may be embodied as hardware, firmware, software, or a combination thereof. Thus, in some embodiments, one or more of the components of the environment 200 may be embodied as a circuit or collection of electrical devices (e.g., the display manager 202, the preference manager 204, the alignment manager 206, and / or the surgical planner 208, etc.). It should be understood that in such embodiments, one or more of those components may form part of the processor 120, the memory 124, the data storage 126, and / or other components of the surgical planning and assistance device 102.

[0043] The preference manager 204 is configured to receive surgeon preferences 210. The surgeon preferences 210 include a target value and one or more boundary values ​​associated with each surgical parameter of an orthopaedic surgical procedure, such as a total knee arthroplasty. The surgical parameters may include resection height, prosthetic component angle, alignment angle, or other parameters associated with the orthopaedic surgical procedure.

[0044] The registration manager 206 is configured to perform a bony registration of the patient's bony anatomy and perform a leg alignment registration of the patient. Performing the bony registration includes receiving an estimate of cartilage loss. Performing the bony registration may also include confirming a predetermined implant size. Performing the leg alignment registration includes measuring a flexion gap of the patient's knee joint and a knee extension gap. Measuring the flexion gap and extension gap may include tracking a plurality of reflective targets 108 coupled to the patient's bony anatomy using a camera 132 coupled to the surgical planning and assistance device 102.

[0045] The surgical planner 208 is configured to determine a surgical plan 212 for the orthopaedic surgical procedure based on the surgeon's preferences 210, the bone alignment, and the leg alignment alignment. The surgical plan 212 includes a planned value associated with each surgical parameter of the orthopaedic surgical procedure. Each planned value may be within one or more boundary values ​​associated with the surgical parameter from the surgeon's preferences 210. The surgical planner 208 may be further configured to determine an updated surgical plan 212 based on the surgeon's preferences 210, the leg alignment alignment, and the updated boundary values. The updated boundary values ​​override the surgeon's preferences 210. The surgical planner 208 may be further configured to control the robotic surgical device 104 to assist in achieving one or more planned values ​​of the surgical plan 212. Controlling the robotic surgical device 104 may include robotically constraining the surgical saw 106 within a geometric plane defined by the one or more planned values ​​and the bone alignment of the surgical plan 212.

[0046] Determining the surgical plan 212 for the orthopaedic surgical procedure may include automatically adjusting tibial coronal alignment, automatically adjusting femoral coronal alignment in response to automatically adjusting the tibial coronal alignment, automatically adjusting femoral flexion in response to automatically adjusting femoral coronal alignment, automatically adjusting femoral rotation in response to automatically adjusting femoral flexion, and automatically adjusting a distal femoral condyle resection height in response to automatically adjusting femoral rotation.

[0047] In some embodiments, automatically adjusting the tibial coronal plane alignment may include determining an initial proximal tibial resection height based on the surgeon's preferences 210 and an estimate of cartilage loss, and iteratively decreasing the proximal tibial resection height such that the coronal angle of the patient's tibia falls within the tibial varus / valgus boundary of the surgeon's preferences 210 while the proximal tibial resection height falls within the minimum proximal tibial resection height boundary of the surgeon's preferences 210. The proximal tibial resection height may be a medial or lateral proximal tibial resection height. In some embodiments, automatically adjusting the tibial coronal plane alignment may include determining whether the medial or lateral high side is high based on bone alignment, and decreasing the proximal tibial resection height on the side other than the high side.

[0048] In some embodiments, automatically adjusting the femoral coronal plane alignment may include determining an initial distal femoral condyle resection height based on a surgeon's preference 210 and an estimate of cartilage loss, and iteratively increasing the distal femoral condyle resection height until the medial extension gap equals the lateral extension gap while the coronal angle of the patient's femur and the distal femoral condyle resection height are within the bounds of the surgeon's preference 210. Automatically adjusting the femoral coronal plane alignment may further include determining the smaller of the medial extension gap and the lateral extension gap and increasing the distal femoral condyle resection height relative to the smaller side.

[0049] In some embodiments, automatically adjusting the femoral flexion may include iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the bounds of the surgeon's preferences 210 until the total flexion gap equals the ideal flexion gap. The total flexion gap is the sum of the lateral flexion gap and the medial flexion gap, and the ideal flexion gap is the sum of the natural joint laxity in flexion and the default component height. If the femoral component flexion / extension angle reaches the bounds, automatically adjusting the femoral flexion may include iteratively adjusting the femoral component anterior / posterior shift while the posterior femoral condyle resection height is within the bounds of the surgeon's preferences 210 until the total flexion gap equals the ideal flexion gap. If the posterior femoral condyle resection height reaches the bounds, automatically adjusting the femoral flexion may include determining the difference between the total flexion gap and the ideal flexion gap and prompting to resize the femoral component if the difference is greater than a default length. If the difference is less than or equal to a predetermined length, automatically adjusting the femoral flexion may include iteratively adjusting the proximal tibial resection height until the difference reaches a predetermined length while the proximal tibial resection height is within the bounds of the surgeon's preference 210. The femoral component flexion / extension angle and the femoral component anterior / posterior shift may be reset in response to a change in femoral component size or an iterative adjustment of the proximal tibial resection height. If the total flexion gap is greater than the ideal flexion gap, iteratively adjusting the femoral component flexion / extension angle includes increasing the femoral component flexion angle, and iteratively adjusting the femoral component anterior / posterior shift includes increasing the femoral component posteriorization. If the total flexion gap is less than the ideal flexion gap, iteratively adjusting the femoral component flexion / extension angle includes decreasing the femoral component flexion angle, and iteratively adjusting the femoral component anterior / posterior shift includes increasing the femoral component anteriorization.

[0050] In some embodiments, automatically adjusting the femoral rotation includes iteratively rotating the femoral component while the posterior femoral condyle resection height is within the bounds of the surgeon's preference 210 until the medial and lateral flexion gaps equal the target medial and lateral flexion gaps. In some embodiments, automatically adjusting the distal femoral condyle resection height includes iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within the bounds of the surgeon's preference 210 until the total extension gap equals the total flexion gap.

[0051] The display manager 202 is configured to present the surgical plan 212 to a user, such as a surgeon. The display manager 202 may be further configured to receive modifications to the surgical plan 212 in response to presenting the surgical plan 212. The modifications may include updated boundary values ​​associated with the surgical parameters. The display manager 202 may be further configured to indicate whether one or more boundaries of the surgeon's preferences 210 have been reached in response to determining the surgical plan 212.

[0052] Referring now to FIG. 3 , in use, the surgical planning and assistance device 102 may perform a method 300 for an orthopaedic surgical procedure using automated surgical planning. It should be understood that in some embodiments, the operations of the method 300 may be performed by one or more components of the environment 200 of the surgical planning and assistance device 102, such as that shown in FIG. 2 . The method 300 begins at block 302, where the device 102 receives surgeon preferences 210 for target and boundary values ​​for various surgical parameters associated with the orthopaedic surgical procedure. For example, the surgeon preferences 210 may include target values ​​for tibial and femoral resection heights, component angles, and other surgical parameters affecting the position of the prosthetic implant components. For each target value, the surgeon preferences 210 may include minimum and maximum values, tolerance ranges, or other boundary conditions. The surgeon preferences 210 may be entered into the device 102 using, for example, a touchscreen or other input device, or the surgeon preferences 210 may be received from a remote device. In some embodiments, surgeon preferences 210 may be predetermined and reused for multiple surgical procedures.

[0053] Referring now to FIG. 4, diagram 400 illustrates one potential embodiment of surgeon preferences 210 that may be received by device 102. Diagram 400 illustrates a graphical user interface for viewing and / or editing surgeon preferences 210 that may be displayed on display 130 of device 102. The surgeon preferences 210 are graphically organized into several preference groupings 402. Each preference grouping 402 includes user interface controls for one or more surgical parameters 404. For each surgical parameter 404, the surgeon may view and / or edit values ​​for a target value 406 and / or one or more boundary values ​​408. These values ​​may be edited using text box controls such as those shown in FIG. 4 or using any other suitable user interface.

[0054] Illustrative diagram 400 shows one illustrative set of surgical parameters 404 that may be associated with surgeon preferences 210. As shown, the illustrative surgeon preferences 210 include distal femoral condyle resection heights for both the medial and lateral distal condyles. Each of these resection heights may include a target value and minimum and maximum boundaries, each of which may be measured in millimeters relative to the most distal point of the most distal condyle. Similarly, the illustrative surgeon preferences 210 include posterior femoral condyle resection heights for both the medial and lateral posterior condyles. Each of these resection heights may include a target value and minimum and maximum boundaries, each of which may be measured in millimeters relative to a reference point (e.g., a point on the anterior cortex of the femur).

[0055] The illustrative surgeon's preferences 210 further include a femoral rotation angle, including a target value and minimum and maximum bounds, each of which may be measured in degrees relative to an anatomical line (e.g., the posterior condylar axis, the Whiteside line, or the transepicondylar axis). Similarly, the illustrative surgeon's preferences 210 further include a femoral component flexion angle, including a target value and minimum and maximum bounds, each of which may be measured in degrees relative to a reference axis (e.g., the sagittal mechanical axis of the femur).

[0056] The illustrative surgeon preferences 210 further include values ​​for the natural joint laxity of the knee in flexion and extension, both medially and laterally. These preferences may each include a target value measured in millimeters.

[0057] The illustrative surgeon's preferences 210 further include both medial and lateral proximal tibial resection heights. Each of these resection heights may include a target value and minimum and maximum bounds, each of which may be measured in millimeters relative to the high side of the tibia. The illustrative surgeon's preferences 210 further include a tibial slope, which illustratively includes a target value measured in degrees. In other embodiments, the surgeon's preferences 210 may include minimum and maximum bounds for the tibial slope, although these bounds are not used in the illustrative embodiment.

[0058] The exemplary surgeon's preferences 210 further include a femoral varus / valgus range, also referred to as a femoral coronal alignment range, which includes minimum and maximum bounds measured in degrees. Similarly, the exemplary surgeon's preferences 210 further include a tibial varus / valgus range, also referred to as a tibial coronal alignment range, which includes minimum and maximum bounds measured in degrees. Furthermore, the exemplary surgeon's preferences 210 further include a hip-knee-ankle (HKA) alignment range, also referred to as a mechanical alignment range, which includes minimum and maximum bounds measured in degrees.

[0059] The illustrative diagram 400 further includes a grouping 410 of calculated values ​​412. The calculated values ​​412 are generated by the device 102 based on one or more other values ​​of the surgeon's preferences 210 and, therefore, are not directly editable. Accordingly, the calculated values ​​412 are displayed using label controls or other read-only user interface elements. Illustratively, the calculated values ​​412 include ideal gap targets for the joint in flexion and extension, for both medial and lateral rotation. As described further below, these ideal gap targets are calculated based on the natural joint laxity targets of the surgeon's preferences 210.

[0060] 3 , after receiving the surgeon's preferences 210 in block 302, the device 102 may provide one or more default values ​​for the target or boundary values ​​in block 304 if the surgeon's preferences 210 are not specified. In block 306, the device 102 calculates user-defined gap target values ​​based on the surgeon's preferences 210. Illustratively, each ideal gap target is equal to the natural joint laxity provided by the user plus a predetermined value that may correspond to the type of implant being used in the surgical procedure (e.g., the thickness of the particular implant component being used). For example, the medial ideal gap in flexion may be the medial natural joint laxity in flexion (provided by the user) plus 8 millimeters or 9 millimeters (depending on the implant being used). Other ideal gap targets may be calculated similarly.

[0061] At block 308, device 102 may perform bone registration of the patient's bony anatomy. To perform bone registration, the surgeon may attach bone array 110 to each of the patient's tibia and femur. The surgeon may use pointer 112 to touch various landmarks on the patient's bony anatomy. During registration, device 102 uses camera 132 to track the position of bone array 110 and pointer 112, thus aligning the position of each landmark on the patient's bony anatomy.

[0062] As part of aligning the bones, device 102 receives cartilage loss estimates from a surgeon or other user at block 310. The surgeon may estimate the amount of cartilage lost (in millimeters) for each of the distal medial condyle, distal lateral condyle, posterior medial condyle, posterior lateral condyle, medial tibia, and lateral tibia. The surgeon or another user may enter these cartilage loss estimates into device 102, for example, using a touchscreen or other input device.

[0063] At block 312, the device 102 prompts the surgeon or other user to confirm the implant size to be used in the orthopaedic surgical procedure. The implant size may be predetermined during pre-operative planning or may otherwise be set to a default value. After being prompted, the surgeon or other user may select a different implant size, which is stored by the device 102 for further processing.

[0064] In block 314, device 102 performs a leg alignment registration to assess the balance of the patient's knee joint throughout the range of motion. During block 314, device 102 captures gap values ​​between the patient's femurs in multiple functional positions, including at least flexion and extension. Based on the leg alignment registration, device 102 determines an ideal flexion gap target and an ideal extension gap target. One potential embodiment of a method for leg alignment registration that may be performed by device 102 is shown in FIG. 5 and described below. If the surgeon performs soft tissue release, device 102 may repeat the leg alignment registration.

[0065] At block 316, the device 102 determines a surgical plan 212 based on the surgeon's preferences 210, bone alignment, and leg alignment registration. The surgical plan 212 includes calculated planned values ​​for each surgical parameter associated with the orthopaedic surgical procedure. As described further below, the device 102 automatically calculates the planned values ​​using an iterative algorithm that converges to planned values ​​that are within the bounds specified by the surgeon's preferences 210 (if possible). For example, the surgical plan can converge to planned values ​​equal to user-defined gap targets (e.g., medial and lateral extension and flexion gap values) or as close as possible to the user-defined gap targets where the surgical parameters are within the bounds. In some embodiments, changes to one or more surgical parameters may affect other surgical parameters, and therefore the device 102 automatically updates the planned values ​​as necessary. Potential embodiments of methods for automatically determining the surgical plan 212 are shown in FIGS. 6-13 and described below.

[0066] After generating the surgical plan 212, the device 102 presents the surgical plan 212 to the surgeon or other user in block 318. The device 102 may use any input / output device or output modality to present the surgical plan 212. In some embodiments, as represented by block 320, the device 102 may use the display 130 to display numerical dimensions of the resection height, angle, position shift, or other parameters of the surgical plan 212. In some embodiments, as represented by block 322, the device 102 may use the display 130 to graphically display the dimensions of the surgical plan 212. For example, the device 102 may graphically render a three-dimensional model of the patient's bony anatomy with prosthetic components positioned relative to the bony anatomy according to the surgical plan 212. One illustrative example of a graphical user interface that may be generated by the device 102 in blocks 320 and 322 is shown in FIG. 14 and described further below. In some embodiments, as represented by block 324, the device 102 may indicate any boundary limits reached when generating the surgical plan 212. For example, the device 102 may highlight, outline, or otherwise emphasize any boundary limits reached during the calculation of the surgical plan 212 (e.g., minimum or maximum resection height, minimum or maximum angle, etc.).

[0067] At block 326, the device 102 receives confirmation or modification of the surgical plan 212 from the surgeon. The surgeon may modify the surgical plan 212 by modifying one or more planning values ​​of the surgical plan 212. For example, the surgeon may increase or decrease a particular resection height or adjust a particular angle. As another example, the surgeon may modify the surgical plan 212 by modifying one or more boundary values ​​of the surgeon's preferences 210. For example, the surgeon may increase a maximum boundary reached or decrease a minimum boundary reached. At block 328, the device 102 determines whether a modification has been received. If not, the method 300 proceeds to block 332, described below. If a modification has been received, the method 300 proceeds to block 330.

[0068] At block 330, the device 102 overrides one or more surgeon's preferences 210 with the surgeon-provided modification values. The device 102 may, for example, override one or more boundary values ​​of the surgeon's preferences 210 to include the surgeon-specified modification values. After overriding the surgeon values, the method 300 loops back to block 316, where the device 102 redetermines the surgical plan 212 using the overridden surgeon's preferences 210.

[0069] Referring back to block 328, if no corrections were received, the method 300 branches to block 332, where the device 102 controls the robotic surgical device 104 according to the surgical plan 212 to assist the surgeon in performing the orthopaedic surgical procedure. The device 102 may transmit the surgical plan 212 to the robotic surgical device 104 or otherwise cause the robotic surgical device 104 to operate according to the surgical plan 212. Illustratively, in block 334, the robotic surgical device 104 robotically constrains the surgical saw 106 to a planned resection plane according to the surgical plan 212. For example, the robotic surgical device 104 may constrain the surgical saw 106 to a resection plane defined by the medial distal femoral condyle resection height of the surgical plan 212. The robotic surgical device 104 may locate this resection plane relative to the patient's anatomy by tracking the bone array 110 using the camera 132 of the device 102, similar to the bone registration process described above. After the surgeon completes this resection, the robotic surgical device 104 can continue to robotically constrain the surgical saw 106 for additional resections based on additional parameters of the surgical plan 212. After controlling the robotic surgical device 104, the method 300 is complete. The surgeon may continue the orthopaedic surgical procedure by, for example, attaching one or more trial components, one or more prostheses, or otherwise completing the orthopaedic surgical procedure.

[0070] Referring now to FIG. 5 , in use, the device 102 may perform a method 500 for leg alignment registration. It should be understood that in some embodiments, the operations of the method 500 may be performed in conjunction with block 314 of FIG. 3 , as described above. The method 500 begins at block 502, where the device 102 captures the patient's joint alignment / position while the patient's knee joint is moved through a range of motion. In particular, the surgeon may articulate the patient's knee joint through a range of motion while the device 102 uses the camera 132 to track the position of the bone array 110, thus aligning the relative positions of the femur 200 and tibia 202 at multiple points within the range of motion. While moving the knee joint through the range of motion, the surgeon may apply varus and valgus forces to represent the surgeon's desired final tension in the medial and collateral ligaments. In block 504, the device 102 stores the captured alignment values ​​as corrected varus / valgus alignment values.

[0071] In block 506, the device 102 compares the target varus / valgus alignment angle of the surgeon's preferences 210 with the measured corrected varus / valgus angle. In particular, the device 102 determines whether the corrected alignment angle is within the target alignment angle boundary. The device 102 may determine whether the corrected alignment angle under varus stress (HKA angle) is greater than or equal to the target HKA varus boundary (e.g., a negative number) and whether the corrected alignment angle under valgus stress (HKA angle) is less than or equal to the target HKA valgus boundary (e.g., a positive number). In block 508, the device 102 determines whether the HKA angle is correctable. The HKA angle may be correctable if the corrected varus / valgus angle is within the target varus / valgus boundary angle as determined in connection with block 506. If the alignment is correctable, the method 500 branches to block 514, described below. If the alignment is not correctable, the method 500 proceeds to block 508 .

[0072] At block 510, the device 102 prompts the surgeon or other user that a soft tissue release may be necessary. The device 102 may display a message, for example, using the display 130. At block 512, the device 102 may repeat the leg alignment registration after the surgeon performs the soft tissue release.

[0073] In block 514, the device 102 acquires gap data throughout the range of motion, including medial and lateral flexion gap information and extension gap information. For example, a surgeon may move the knee joint through its full range of motion from extension to flexion. The surgeon may apply a varus force while moving the knee through the range of motion, and the surgeon may repeatedly move the knee through the range of motion while applying a valgus force. The device 102 captures flexion and extension gap information by recording the movement of the bone array 110 using the camera 132 throughout the range of motion. Other techniques for capturing gap data throughout the range of motion may be employed, such as recording only extension and flexion.

[0074] At block 516, the device 102 determines a total flexion gap and a total extension gap. The total flexion gap is the medial flexion gap added to the lateral flexion gap; similarly, the total extension gap is the medial extension gap added to the lateral extension gap. At block 518, the device 102 determines an ideal flexion gap and an ideal extension gap. The ideal flexion gap is equal to the medial flexion gap target plus the lateral flexion gap target, and the ideal extension gap is equal to the medial extension gap target plus the lateral extension gap target. These gap values ​​are used during the automated determination of the surgical plan 212, as described further below. In some embodiments, the presence of kyphosis can be accounted for by subtracting 1.5 mm from the medial extension gap target and the lateral extension gap target. This functionality can be provided, for example, in response to a toggle switch or other user interface control that can be activated before or after the surgical plan 212 is created. After determining the ideal flexion and extension gaps, the method 500 is complete. The device 102 may continue to perform the method 300 shown in FIG. 3 and described above.

[0075] Referring now to FIG. 6 , in use, the device 102 may perform a method 600 for automatic surgical planning. It should be understood that in some embodiments, the operations of the method 600 may be performed in conjunction with block 316 of FIG. 3 , described above. The method 600 begins at block 602, in which the device 102 automatically adjusts tibial coronal alignment in the surgical plan 212. To adjust the tibial coronal alignment, the device 102 iteratively adjusts the medial and lateral proximal tibial resection heights while staying within the bounds of the proximal tibial resection height and tibial varus / valgus angle from the surgeon's preferences 210. One potential embodiment of a method for automatically adjusting tibial coronal alignment is shown in FIG. 7 and described below (see also the graphical representations 1424, 1430 of FIG. 14 ).

[0076] In block 604, the device 102 automatically adjusts the femoral coronal alignment in the surgical plan 212. To adjust the femoral coronal alignment, the device 102 iteratively adjusts the medial and lateral distal femoral condyle resection heights while staying within the boundaries of the distal femoral condyle resection height and femoral varus / valgus angle from the surgeon's preferences 210. One potential embodiment for automatically adjusting the femoral coronal alignment is shown in FIG. 8 and described below (see also the graphical representation 1402 in FIG. 14).

[0077] After adjusting the tibial and femoral coronal alignment, device 102 automatically adjusts femoral flexion in block 606. To adjust femoral flexion, device 102 iteratively adjusts femoral component flexion / extension angle and anterior / posterior shift while staying within the bounds of the flexion gap and posterior femoral condyle resection height from surgeon's preferences 210. In some circumstances, device 102 may also iteratively adjust the proximal tibial resection height previously determined as described above in connection with block 602 while also staying within the bounds of the proximal tibial resection height from surgeon's preferences 210. The particular strategy used to adjust femoral flexion and anterior / posterior shift may depend on whether the flexion gap is initially greater than ideal (i.e., too loose) or less than ideal (i.e., too tight). Potential embodiments of methods for automatically adjusting femoral flexion are shown in FIGS. 9-11 and described below (see also graphical representation 1418 in FIG. 14).

[0078] At block 608, the device 102 automatically adjusts the femoral rotation. The device 102 may iteratively adjust the femoral rotation, which may cause a corresponding change in the posterior femoral condyle resection height. Thus, the device 102 may adjust the femoral rotation while staying within the bounds of the posterior femoral condyle resection height from the surgeon's preferences 210. One potential embodiment for automatically adjusting the femoral rotation is shown in FIG. 12 and described below (see also the graphical representation 1410 of FIG. 14).

[0079] In block 610, the device 102 automatically adjusts the medial and lateral distal femoral condyle resection heights while staying within the distal femoral condyle resection height boundaries from the surgeon's preferences 210. Note that adjusting the distal femoral condyle resection heights also affects the extension gap. One potential embodiment for automatically adjusting the distal femoral condyle resection heights is shown in FIG. 13 and described below (see also the graphical representation 1410 of FIG. 14). After adjusting the distal femoral condyle resection heights, the method 600, and therefore the surgical plan 212, is complete. The device 102 may continue to present the determined surgical plan 212 as described above in connection with the method 300 of FIG. 3.

[0080] Referring now to FIG. 7 , in use, the device 102 may perform a method 700 for automatically adjusting tibial coronal alignment. It should be understood that in some embodiments, the operations of the method 700 may be performed in conjunction with block 602 of FIG. 6 , as described above. The method 700 begins at block 702, where the device 102 determines the high side of the tibia based on bone alignment. According to the bone alignment, the device 102 may identify either the medial tibial plateau or the lateral tibial plateau as the high side based on which side has the most proximal point. At block 704, the device 102 determines whether the high side is the lateral side. If so, the method 700 branches to block 708. If the high side is not the lateral side, the method 700 proceeds to block 706, where the device 102 prompts the user to verify the tibial alignment.

[0081] At block 708, the device 102 determines initial medial and lateral proximal tibial resection heights based on the target values ​​and the estimated cartilage loss from the surgeon's preferences 210. For example, the initial medial proximal tibial resection height may be the target medial resection height minus the estimated medial tibial cartilage loss, and the initial lateral proximal tibial resection height may be the target lateral resection height minus the estimated lateral tibial cartilage loss.

[0082] At block 710, the device 102 determines the tibial varus / valgus joint line angle based on the medial and lateral proximal tibial resection heights. At block 712, the device 102 tests the varus / valgus joint line angle against the tibial varus / valgus boundaries of the surgeon's preferences 210. In particular, the device 102 may determine whether the angle is between the maximum valgus and maximum varus boundaries. At block 714, the device 102 determines whether the tibial varus / valgus joint line angle is within the boundaries. If so, the method 700 proceeds to block 722, described below. If the tibial varus / valgus joint line angle is not within the boundaries, the method 700 proceeds to block 716. In some embodiments, the presence of patellofemoral instability may be accounted for by limiting the degree of rotation, by tibial varus, and by extension. This functionality may be provided, for example, in response to a toggle switch or other user interface control that may be activated before or after the surgical plan 212 is created.

[0083] At block 716, the device 102 incrementally decreases the lower proximal tibia resection height. The device 102 may decrease the lower resection height by a small amount, such as 0.5 mm. For example, if the lateral side is the higher side, the device 102 may decrease the medial proximal tibia resection height by 0.5 mm. At block 718, the device 102 tests the lower resection height against the minimum proximal tibia resection height boundary of the surgeon's preferences 210, for example, by determining whether the lower resection height is greater than or equal to the minimum boundary. At block 720, the device 102 determines whether the lower proximal tibia resection height is within the boundary. If so, the method 700 loops back to block 710, where the device 102 continues to incrementally adjust the resection height. If the lower proximal tibia resection height is not within the boundary (e.g., less than and / or less than the minimum boundary), the method 700 proceeds to block 722.

[0084] At block 722, the device 102 records temporary or provisional medial proximal tibia resection heights and lateral proximal tibia resection heights. As described further below, these temporary or provisional values ​​may be further adjusted while determining other parameters of the surgical plan 212. After recording the medial and lateral proximal tibia resection heights, the method 700 is complete. The device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6.

[0085] Referring now to FIG. 8 , in use, the device 102 may perform a method 800 for automatically adjusting femoral coronal alignment. It should be understood that in some embodiments, the operations of the method 800 may be performed in conjunction with block 604 of FIG. 6 , as described above. The method 800 begins at block 802, where the device 102 determines initial values ​​for the medial distal femoral condyle resection height and the lateral distal femoral condyle resection height based on target values ​​from the surgeon's preferences 210 and estimated cartilage loss. For example, the medial distal femoral condyle resection height may be equal to the target medial distal femoral condyle resection height minus the estimated medial distal femoral condyle cartilage loss, and the lateral distal femoral condyle resection height may be equal to the target lateral distal femoral condyle resection height minus the estimated lateral distal femoral condyle cartilage loss. In block 804, the device 102 determines the pivot point as the opposite side of the joint from the side with the smallest extension gap. For example, if the medial extension gap is smaller than the lateral extension gap, the pivot point is lateral, and if the medial extension gap is larger than the lateral extension gap, the pivot point is medial.

[0086] In block 806, the device 102 determines whether the medial and lateral extension gaps are equal. Initial values ​​for the medial and lateral extension gaps are determined during leg alignment registration, as described above. The calculated values ​​for the medial and lateral extension gaps may be determined in response to adjustments to the distal femoral condyle extension gap. In block 808, the device 102 checks whether the medial and lateral extension gaps are equal. If so, the method 800 branches to block 822, described below. If not, the method 800 proceeds to block 810.

[0087] In block 810, the device 102 incrementally increases the distal femoral condyle resection height on the side of the joint with the smallest extension gap. The device 102 may incrementally increase the resection height by a small amount, such as 0.5 mm. For example, if the medial side has the smallest gap, the device 102 may increase the medial distal femoral condyle resection height by 0.5 mm, and if the lateral side has the smallest gap, the device 102 may increase the lateral distal femoral condyle resection height by 0.5 mm.

[0088] At block 812, the device 102 determines the femoral varus / valgus angle based on the medial and lateral distal femoral condyle resection heights. At block 814, the device 102 tests the varus / valgus angle against the femoral varus / valgus boundaries of the surgeon's preferences 210. In particular, the device 102 may determine whether the angle is between the maximum valgus and maximum varus boundaries. At block 816, the device 102 determines whether the femoral varus / valgus joint line angle is within the boundaries. If not, the method 800 proceeds to block 822, described below. If the femoral varus / valgus joint line angle is within the bounds, the method 800 proceeds to block 818, where the device 102 tests the medial and lateral distal femoral condyle resection heights against the maximum medial and lateral distal femoral condyle resection height bounds of the surgeon's preferences 210, for example, by determining whether each distal femoral condyle resection height is less than or equal to the maximum bounds. In block 820, the device 102 determines whether the medial and lateral distal femoral condyle resection heights are within the bounds. If so, the method 800 loops back to block 806, where the device 102 continues to incrementally adjust the resection heights until the medial and lateral extension gaps are equal. If the medial and lateral distal femoral condyle resection heights are not within the bounds (e.g., greater than and / or greater than the maximum bounds), the method 800 proceeds to block 822.

[0089] At block 822, the device 102 records temporary or provisional medial and lateral distal femoral condyle resection heights. As described further below, these temporary or provisional values ​​may be further adjusted while determining other parameters of the surgical plan 212. After recording the medial and lateral distal femoral condyle resection heights, the method 800 is complete. The device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6.

[0090] Referring now to FIG. 9 , in use, the device 102 may perform a method 900 for automatically adjusting femoral flexion. It should be understood that in some embodiments, the operations of the method 900 may be performed in conjunction with block 606 of FIG. 6 , described above. The method 900 begins at block 902, where the device 102 compares the total flexion gap to an ideal flexion gap. At block 904, the device 102 checks whether the total flexion gap is greater than the ideal flexion gap. If not, the method 900 proceeds to block 908, described below. If the total flexion gap is greater than the ideal flexion gap, the method 900 proceeds to block 906.

[0091] In block 906, the device 102 iteratively adjusts the femoral component flexion and posteriorization in the surgical plan 212. The device 102 maintains the femoral component flexion and posteriorization within the boundaries of the surgeon's preferences 210. Once these boundaries are met, the device 102 may also adjust the medial and lateral proximal tibial resection heights and / or the implant size in use. One potential embodiment of a method for adjusting femoral flexion and posteriorization is shown in FIG. 10 and described below.

[0092] At block 908, the device 102 determines whether the total flexion gap is less than the ideal flexion gap. If not (i.e., if the total flexion gap is equal to the ideal flexion gap), the method 900 branches to block 912, described below. If the total flexion gap is less than the ideal flexion gap, the method 900 proceeds to block 910.

[0093] In block 906, the device 102 iteratively adjusts the femoral component flexion and anteriorization in the surgical plan 212. The device 102 maintains the femoral component flexion and anteriorization within the boundaries of the surgeon's preferences 210. Once these boundaries are met, the device 102 may also adjust the medial and lateral proximal tibial resection heights and / or the implant size in use. One possible embodiment of a method for adjusting flexion and anteriorization is shown in FIG. 11 and described below.

[0094] After properly adjusting the femoral component flexion and / or anterior / posterior shift, the device 102 records the planned total flexion gap in block 912. In block 914, the device 102 records the planned medial and lateral proximal tibial resection heights, for example, in the surgical plan 212.

[0095] At block 916, the device 102 determines whether any tibial resection boundaries have been reached. For example, the device 102 may determine whether the medial proximal tibia resection height is equal to the minimum or maximum medial proximal tibia resection height, and similarly, the device 102 may determine whether the lateral proximal tibia resection height is equal to the minimum or maximum lateral proximal tibia resection height. At block 918, the device 102 checks whether either boundary has been reached. If not, the method 900 is complete. The device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6 . Referring again to block 918, if any proximal tibia resection height boundaries have been met, the method 900 proceeds to block 920, where the device 102 alerts the user that the resection boundaries have been met. After alerting the user, the method 900 is complete, and the device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6 . If desired, the user may modify the surgical plan 212 (eg, to adjust certain boundaries that have been filled), as described above in connection with FIG.

[0096] Referring now to FIG. 10 , in use, the device 102 may perform a method 1000 for automatically adjusting femoral component flexion and posteriorization. It should be understood that in some embodiments, the operations of the method 1000 may be performed in connection with block 906 of FIG. 9 , as described above. The method 1000 begins at block 1002, in which the device 102 iteratively increases the femoral component flexion angle in the surgical plan 212 until the total flexion gap equals the ideal flexion gap or reaches the flexion boundary of the surgeon's preference 210. For example, the device 102 may increase the flexion angle by a small amount (e.g., 0.5 degrees, 1 degree, or other small amount) and then update other affected parameters of the surgical plan 212, including the medial and lateral posterior femoral condyle resection heights. Based on the updated surgical plan 212, the device 102 may update the total flexion gap to equal the lateral flexion gap plus the medial flexion gap. The device 102 may test the flexion gap and surgeon preferred boundaries after incrementing femoral flexion for each iteration.

[0097] At block 1004, the device 102 checks whether the total flexion gap is equal to the ideal flexion gap. If so, the method 1000 is complete. The device 102 may continue to automatically adjust the flexion gap as described above in connection with FIG. 9. Referring again to block 1004, if the total flexion gap is not equal to the ideal flexion gap (i.e., the flexion boundary and / or minimum posterior femoral condyle resection height boundary has been reached), the method 1000 proceeds to block 1006.

[0098] In block 1006, the device 102 iteratively posteriorizes the femoral component in the surgical plan 212 until the total flexion gap equals the ideal flexion gap or reaches the posterior femoral condyle resection height minimum boundary of the surgeon's preference 210. For example, the device 102 may move the femoral component in the posterior direction a small amount (e.g., 0.5 mm) and then update other affected parameters of the surgical plan 212, including the medial and lateral posterior femoral condyle resection heights. Based on the updated surgical plan 212, the device 102 may update the total flexion gap. The device 102 may test the flexion gap and the surgeon's preference boundary after incrementing the posteriorization of the femoral component for each iteration.

[0099] At block 1008, the device 102 checks whether the total flexion gap is equal to the ideal flexion gap. If so, the method 1000 is complete. The device 102 may continue to automatically adjust the femoral flexion, as described above in connection with FIG. 9. Referring again to block 1008, if the total flexion gap is not equal to the ideal flexion gap (i.e., the minimum posterior femoral condyle resection height boundary has been reached), the method 1000 proceeds to block 1010.

[0100] In block 1010, the device 102 determines the difference between the current total flexion gap and the ideal flexion gap. If the difference is less than or equal to 3 millimeters, the method 1000 branches to block 1020, described below. If the difference is greater than 3 millimeters, the method 1000 proceeds to block 1016. While illustrated as testing the difference against 3 millimeters, it should be understood that in other embodiments, the difference may be tested against a different predetermined length. For example, the difference may be tested against the difference in anterior-posterior length between different available sizes of femoral components, which in the illustrative embodiment is 3 mm.

[0101] At block 1014, device 102 prompts the user to increase the size of the femoral component. As described above, in the illustrative embodiment, femoral components are available in multiple pre-defined sizes, which differ from each other in 3-millimeter increments in the anterior-posterior dimension. Thus, if the difference between the current total flexion gap and the ideal flexion gap is greater than 3 millimeters, the surgeon may consider increasing the size of the femoral component to reduce the flexion gap. In response to the prompt, the surgeon or other user may instruct device 102 to increase the femoral component size, for example, using touchscreen display 130. At block 1016, device 102 checks whether the surgeon or other user has requested to change the component size. If so, method 1000 proceeds to block 1020, described below. If the user selects to increase the femoral component size, the method 1000 branches to block 1018, where the device 102 increases the femoral component size accordingly and then resets the femoral component flexion and posteriorization to default values. After resetting the femoral component flexion and posteriorization, the method 1000 loops back to block 1002 to continue automatically adjusting the femoral flexion and posteriorization.

[0102] Referring again to blocks 1012 and 1016, if the size difference is less than or equal to 3 millimeters or the user does not increase the size of the femoral component, the method 1000 proceeds to block 1020. In block 1020, the device 102 iteratively reduces the proximal tibia resection height of the surgical plan 212 until the difference between the total flexion gap and the ideal flexion gap reaches 3 millimeters or until the proximal tibia resection height minimum boundary of the surgeon's preference 210 is reached. For example, the device 102 may reduce the medial and lateral proximal tibia resection heights by a small amount (e.g., 0.5 mm) and then update the total flexion gap. The device 102 may test the flexion gap and the surgeon's preference boundary after decrementing the proximal tibia resection height for each iteration.

[0103] At block 1022, the device 102 determines whether the proximal tibia resection height has reached a minimum boundary. If not, the method 1022 branches to block 1018, where the device 102 resets the femoral component flexion and posteriorization and continues to automatically adjust flexion and posteriorization as described above. Referring back to block 1022, if the proximal tibia resection height minimum boundary has been reached, the method 1000 is complete. The device 102 may continue to automatically adjust the femoral flexion as described above in connection with FIG. 9, and the device 102 may continue to automatically determine the surgical plan 212 as described above in connection with FIG. 6. As described above, the device 102 may indicate to the surgeon that the boundary has been met, and the surgeon may update the surgeon's preferences 210.

[0104] Referring now to FIG. 11 , in use, the device 102 may execute a method 1100 for automatically adjusting femoral component flexion and anteriorization. It should be understood that in some embodiments, the operations of the method 1100 may be performed in conjunction with block 910 of FIG. 9 , as described above. The method 1100 begins at block 1102, in which the device 102 iteratively decreases the femoral component flexion angle in the surgical plan 212 until the total flexion gap equals the ideal flexion gap or reaches the extension boundary of the surgeon's preference 210. For example, the device 102 may decrease the flexion angle by a small amount (e.g., 0.5 degrees, 1 degree, or other small amount) and then update other affected parameters of the surgical plan 212, including the medial and lateral posterior femoral condyle resection heights. Based on the updated surgical plan 212, the device 102 may update the total flexion gap to equal the lateral flexion gap plus the medial flexion gap. The device 102 may test the flexion gap and surgeon preferred boundaries after decrementing the femoral flexion for each iteration.

[0105] At block 1104, the device 102 checks whether the total flexion gap is equal to the ideal flexion gap. If so, the method 1100 is complete. The device 102 may continue to automatically adjust the femoral flexion, as described above in connection with FIG. 9. Referring again to block 1104, if the total flexion gap is not equal to the ideal flexion gap (i.e., the extension boundary and / or maximum posterior femoral condyle resection height boundary has been reached), the method 1100 proceeds to block 1106.

[0106] In block 1106, the device 102 iteratively anteriorizes the femoral component in the surgical plan 212 until the total flexion gap equals the ideal flexion gap or reaches the posterior femoral condyle resection height maximum bound of the surgeon's preference 210. For example, the device 102 may move the femoral component in the anterior direction by a small amount (e.g., 0.5 mm) and then update other affected parameters of the surgical plan 212, including the medial and lateral posterior femoral condyle resection heights. Based on the updated surgical plan 212, the device 102 may update the total flexion gap. The device 102 may test the flexion gap and the surgeon's preference bound after incrementing the anteriorization of the femoral component for each iteration.

[0107] At block 1108, the device 102 checks whether the total flexion gap is equal to the ideal flexion gap. If so, the method 1100 is complete. The device 102 may continue to automatically adjust the femoral flexion, as described above in connection with FIG. 9. Referring again to block 1108, if the total flexion gap is not equal to the ideal flexion gap (i.e., the maximum posterior femoral condyle resection height boundary has been reached), the method 1100 proceeds to block 1110.

[0108] In block 1110, the device 102 determines the difference between the current total flexion gap and the ideal flexion gap. If the difference is less than or equal to 3 millimeters, the method 1100 branches to block 1120, described below. If the difference is greater than 3 millimeters, the method 1100 proceeds to block 1116. While illustrated as testing the difference against 3 millimeters, it should be understood that in other embodiments, the difference may be tested against a different predetermined length. For example, the difference may be tested against the difference in anterior-posterior length between different available sizes of femoral components, which in the illustrative embodiment is 3 mm.

[0109] At block 1114, device 102 prompts the user to decrease the size of the femoral component. As described above, in the illustrative embodiment, femoral components are available in multiple pre-defined sizes, which differ from each other in 3-millimeter increments in the anterior-posterior dimension. Thus, if the difference between the current total flexion gap and the ideal flexion gap is greater than 3 millimeters, the surgeon may consider decreasing the size of the femoral component to increase the flexion gap. In response to the prompt, the surgeon or other user may instruct device 102 to decrease the femoral component size, for example, using touchscreen display 130. At block 1116, device 102 checks whether the surgeon or other user has requested to change the component size. If so, method 1100 proceeds to block 1120, described below. If the user selects to decrease the femoral component size, the method 1100 branches to block 1118, where the device 102 decreases the femoral component size accordingly and then resets the femoral component flexion and anteriorization to default values. After resetting the femoral component flexion and anteriorization, the method 1100 loops back to block 1102 to continue automatically adjusting the femoral flexion and anteriorization.

[0110] Referring again to blocks 1112 and 1116, if the size difference is less than or equal to 3 millimeters or the user does not reduce the size of the femoral component, the method 1100 proceeds to block 1120. In block 1120, the device 102 iteratively increases the proximal tibia resection height of the surgical plan 212 until the difference between the total flexion gap and the ideal flexion gap reaches 1 millimeter or until the proximal tibia resection height maximum bound of the surgeon's preferences 210 is reached. For example, the device 102 may increase the medial and lateral proximal tibia resection heights by a small amount (e.g., 0.5 mm) and then update the total flexion gap. The device 102 may test the flexion gap and the surgeon's preference bound after incrementing the proximal tibia resection height for each iteration.

[0111] At block 1122, the device 102 determines whether the proximal tibia resection height has reached its maximum boundary. If not, the method 1122 branches to block 1118, where the device 102 resets the femoral component flexion and anteriorization and continues to automatically adjust the femoral flexion and anteriorization as described above. Referring back to block 1122, if the proximal tibia resection height maximum boundary has been reached, the method 1100 is complete. The device 102 may continue to automatically adjust the femoral flexion as described above in connection with FIG. 9, and the device 102 may continue to automatically determine the surgical plan 212 as described above in connection with FIG. 6. As described above, the device 102 may indicate to the surgeon that the boundary has been met, and the surgeon may update the surgeon's preferences 210.

[0112] Referring now to FIG. 12 , in use, the device 102 may perform a method 1200 for automatically adjusting femoral rotation. It should be understood that in some embodiments, the operations of the method 1200 may be performed in connection with block 608 of FIG. 6 , described above. The method 1200 begins at block 1202, where the device 102 compares the current medial and lateral flexion gaps to the target medial and lateral flexion gaps from the surgeon's preferences 210. The device 102 may determine the current medial and lateral flexion gaps based on the current surgical parameters of the leg alignment registration and surgical plan 212. At block 1204, the device 102 determines whether each of the medial and lateral flexion gaps is equal to the corresponding medial and lateral target flexion gap. If so, the method 1200 proceeds to block 1216, described below. If the flexion gaps are not equal to the target values, the method 1200 proceeds to block 1206.

[0113] In block 1206, the device 102 incrementally rotates the femoral component toward the target values ​​in the surgical plan 212. For example, the device 102 may adjust the femoral component rotation angle by a small amount (e.g., 0.5 degrees, 1 degree, or other small amount) in a direction that moves the medial and lateral flexion gaps closer to their target values. For example, if the medial flexion gap is larger than the target medial flexion gap, the femoral component may be rotated toward the medial side to reduce the medial flexion gap. As another example, if the medial flexion gap is smaller than the target medial flexion gap, the femoral component may be rotated away from the medial side to increase the medial flexion gap. After adjusting the femoral rotation, the device 102 updates other affected parameters of the surgical plan 212, including the medial and lateral posterior femoral condyle resection heights. In block 1208, the device 102 tests the updated medial and lateral posterior femoral condyle resection heights against the minimum and maximum posterior femoral condyle resection height bounds of the surgeon's preferences 210. In block 1210, the device 102 checks whether the medial and lateral posterior femoral condyle resection heights are within minimum and maximum bounds. If so, the method 1200 loops back to block 1202 to continue adjusting the rotation of the femoral component. If not, the method 1200 proceeds to block 1212.

[0114] In block 1212, the device 102 alerts the surgeon or other user that the ideal flexion gap target was not achieved. The device 102 may display a warning on the display 130 or otherwise alert the user. In block 1214, the device 102 indicates the failed resection boundaries, for example, the medial or lateral posterior femoral condyle resection height minimum boundary or the medial or lateral posterior femoral condyle resection height maximum boundary. In some embodiments, the surgeon may adjust the failed boundaries and regenerate the surgical plan 212 as described above.

[0115] After equalizing the medial and lateral flexion gaps or reaching the resection boundaries, the device 102 records the planned medial and lateral posterior femoral condyle resection heights in the surgical plan 212 in block 1216. After recording those resection heights, the method 1200 is complete, and the device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6. If desired, the user may modify the surgical plan 212 (e.g., to adjust certain boundaries that have been filled), as described above in connection with FIG. 3.

[0116] Referring now to FIG. 13 , in use, the device 102 may perform a method 1300 for automatically adjusting the medial and lateral distal femoral condyle resection heights. It should be understood that in some embodiments, the operations of the method 1300 may be performed in connection with block 610 of FIG. 6 , as described above. The method 1300 begins at block 1302, where the device 102 compares the current total extension gap to the planned total flexion gap, determined as described above in connection with FIG. 12 . The device 102 may determine the current total extension gap based on the leg alignment registration and current surgical parameters of the surgical plan 212. In block 1304, the device 102 determines whether the total extension gap is equal to the total flexion gap. If so, the method 1300 proceeds to block 1316, described below. If the flexion gap and extension gap are not equal, the method 1300 proceeds to block 1306.

[0117] In block 1306, the device 102 incrementally adds or subtracts the distal femoral condyle resection heights in the surgical plan 212 to adjust the extension gap toward the planned flexion gap. For example, the device 102 may adjust both the medial distal femoral condyle resection height and the lateral distal femoral condyle resection height by a small amount (e.g., another small amount of 0.5 mm) in a direction that moves the total extension gap closer to the flexion gap. For example, if the total extension gap is greater than the total flexion gap, the distal femoral condyle resection height may be reduced to reduce the total extension gap. As another example, if the total extension gap is less than the total flexion gap, the distal femoral condyle resection height may be increased to increase the medial flexion gap. In block 1308, the device 102 tests the updated medial and lateral distal femoral condyle resection heights against the minimum and maximum distal femoral condyle resection height boundaries of the surgeon's preferences 210. In block 1310, the device 102 checks whether the medial and lateral distal femoral condyle resection heights are within minimum and maximum bounds. If so, the method 1300 loops back to block 1302 to continue adjusting the extension gap. If not, the method 1300 proceeds to block 1312.

[0118] In block 1312, the device 102 alerts the surgeon or other user that the ideal extension gap target was not achieved. The device 102 may display a warning on the display 130 or otherwise alert the user. In block 1314, the device 102 indicates the failed resection boundaries, for example, the medial or lateral distal femoral condyle resection height minimum boundary or the medial or lateral distal femoral condyle resection height maximum boundary. In some embodiments, the surgeon may adjust the failed boundaries and regenerate the surgical plan 212 as described above.

[0119] After equalizing the extension and flexion gaps or reaching the resection boundaries, the device 102 records the planned medial and lateral distal femoral condyle resection heights in the surgical plan 212 at block 1316. After recording those resection heights, the method 1300 is complete, and the device 102 may continue to automatically determine the surgical plan 212, as described above in connection with FIG. 6. If desired, the user may modify the surgical plan 212 (e.g., to adjust certain boundaries that have been filled), as described above in connection with FIG. 3. In some embodiments, the surgical plan 212 may be presented to the user, and the user may modify the surgical plan 212 using a graphical user interface, as described below.

[0120] 14 , an illustrative embodiment of a graphical user interface 1400 that may be provided by device 102 using touchscreen display 130 is shown. Device 102 may provide user interface 1400, for example, to allow a surgeon or other user to view and / or modify surgeon preferences 210. Accordingly, user interface 1400 includes a number of user interface controls that allow a surgeon or other user to view and edit the values ​​of surgeon preferences 210. As shown in FIG. 14 , user interface 1400 also includes a graphical representation of the current surgical plan 212 in relation to the patient's anatomy.

[0121] The user interface 1400 includes a graphical representation 1402 of an anterior view of the femoral component superimposed on the femur in extension, illustrating femoral coronal alignment. This portion of the user interface 1400 also includes controls 1404, 1406 for medial and lateral distal femoral condyle resection heights, respectively. A user may input target values ​​for the distal femoral condyle resection heights by tapping or otherwise activating the associated user controls 1404, 1406. Additionally, in some embodiments, a user may input boundary values ​​(e.g., maximum and minimum resection heights) using the user controls 1404, 1406, for example, by activating one or more pop-up windows or other user interface controls. As the user edits one or more of the distal femoral condyle resection heights, the corresponding lines shown in the graphical representation 1402 may be updated accordingly. Similarly, user interface 1400 also includes a control 1408 that can be used to edit the boundaries (e.g., minimum and maximum angles) of the femoral varus / valgus range. Additionally, the content of control 1408 and / or the dashed line in representation 1402 can be updated to indicate the femoral varus / valgus angle based on the target value of the distal femoral condyle resection height.

[0122] The user interface 1400 further includes a graphical representation 1410 of the femoral component superimposed on a flexed femur, illustrating femoral rotation. This portion of the user interface 1400 also includes controls 1412, 1414 for medial and lateral posterior femoral condyle resection heights, respectively. A user may input target values ​​for the posterior femoral condyle resection heights by tapping or otherwise activating the associated user controls 1412, 1414. Additionally, in some embodiments, a user may input boundary values ​​(e.g., maximum and minimum resection heights) using the user controls 1412, 1414, for example, by activating one or more pop-up windows or other user interface controls. As a user edits one or more of the posterior femoral condyle resection heights, the corresponding line shown in the graphical representation 1410 may be updated accordingly. Similarly, the user interface 1400 also includes a control 1416 for femoral rotation. Control 1416 can also be used to edit the boundaries of femoral rotation (e.g., minimum and maximum angles). Additionally, the contents of control 1416 can be updated based on changes to the posterior femoral condyle resection height in controls 1412, 1414, and vice versa.

[0123] User interface 1400 also includes a graphical representation 1422 of a lateral view of the femoral component superimposed on the femur in extension, illustrating femoral flexion and anterior / posterior shift. This portion of user interface 1400 includes controls 1420 that allow the user to view and / or edit the femoral flexion and may be used to edit the femoral flexion boundaries (e.g., minimum and maximum values). Control 1422 allows the user to view, and in some embodiments, edit, the femoral component anterior / posterior shift (i.e., anteriorization). In some embodiments, the content of control 1422 may be updated in response to changes in the posterior femoral condyle resection height from controls 1412, 1414, or vice versa.

[0124] As shown, the user interface 1400 further includes a graphical representation 1424 of an anterior view of the tibia illustrating the tibial resection height component of the tibial coronal alignment. This portion of the user interface 1400 also includes controls 1426, 1428 for the medial tibial resection height and the lateral tibial resection height, respectively. A user may input a target value for the tibial resection height by tapping or otherwise activating the associated user control 1426, 1428. Additionally, in some embodiments, a user may input boundary values ​​(e.g., maximum and minimum resection heights) using the user controls 1426, 1428, for example, by activating one or more pop-up windows or other user interface controls.

[0125] The user interface 1400 includes a graphical representation 1430 of another anterior view of the tibia illustrating the varus / valgus angle components of the tibial coronal alignment. User controls 1432 can be used to edit the boundaries (e.g., minimum and maximum angles) of the tibial varus / valgus range. Additionally, the content of the controls 1432 and / or the dashed lines in the representation 1430 can be updated to indicate the tibial varus / valgus angle based on the target value of the tibial resection height.

[0126] User interface 1400 further includes a graphical representation 1434 of a lateral view of the tibia illustrating the slope of the tibia. User controls 1434 can be used to view and edit the target value of the tibial slope, and in some embodiments, to edit the boundary values ​​(e.g., minimum and maximum angles) of the tibial slope.

[0127] The user interface 1400 may also include additional user interface elements that provide additional information and / or enable a surgeon or other user to perform additional functions. For example, the illustrative user interface 1400 includes a control group 1438 that allows a user to specify an implant type and / or size. Updates to the implant type or size may be reflected in the various graphical representations 1402, 1410, 1418, 1424, 1430, 1434 of the user interface 1400. The illustrative user interface 1400 further includes a balance graph 1440 that may be updated based on values ​​derived from bone alignment, leg alignment, and / or surgeon preferences 210.

[0128] While certain illustrative embodiments have been set forth in detail in the drawings and foregoing description, it is understood that such illustration and description are merely exemplary in nature and should not be regarded as limiting, but merely have illustrated and described illustrative embodiments, and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.

[0129] The present disclosure has multiple advantages based on various features of the methods, apparatus, and systems described herein. It should be noted that alternative embodiments of the methods, apparatus, and systems of the present disclosure may not include all of the described features, but still benefit from at least some of the advantages of such features. Those skilled in the art will readily be able to independently implement methods, apparatus, and systems that incorporate one or more of the features of the present invention and are within the spirit and scope of the present disclosure as defined in the appended claims.

[0130] [Embodiment] (1) A method for generating a surgical plan for an orthopedic surgical procedure, comprising: receiving, by a computer system, a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of the orthopaedic surgical procedure; performing a bony registration of the patient's bony anatomy using the computer system; performing a leg alignment registration of the patient with the computer system, the leg alignment registration including measuring a flexion gap of the patient's knee joint and measuring an extension gap of the patient's knee joint; determining, by the computer system, a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the bone alignment, and the leg alignment alignment, wherein the surgical plan includes planned values ​​associated with the surgical parameters of the orthopaedic surgical procedure, and the planned values ​​are within the one or more boundary values ​​associated with the surgical parameters. (2) presenting the surgical plan to a user by the computer system; and receiving, by the computer system, modifications to the surgical plan in response to presenting the surgical plan, the modifications including updated boundary values ​​associated with the surgical parameters; 2. The method of claim 1, further comprising determining, by the computer system, an updated surgical plan for the orthopedic surgical procedure based on the preferences of the plurality of surgeons, the bone alignment, the leg alignment registration, and the updated boundary values, wherein the updated boundary values ​​override at least one of the preferences of the plurality of surgeons. (3) determining the surgical plan for the orthopedic surgical procedure; automatically adjusting the tibial coronal alignment; automatically adjusting a femoral coronal alignment in response to automatically adjusting the tibial coronal alignment; automatically adjusting femoral flexion in response to automatically adjusting the femoral coronal alignment; automatically adjusting femoral rotation in response to automatically adjusting the femoral flexion; and 2. The method of claim 1, further comprising automatically adjusting a distal femoral condyle resection height in response to automatically adjusting the femoral rotation. (4) automatically adjusting the tibial coronal plane alignment; determining an initial proximal tibial resection height based on the surgeon's preference and an estimate of cartilage loss; 4. The method of claim 3, further comprising iteratively decreasing the proximal tibia resection height while the proximal tibia resection height is within the surgeon's preferred minimum proximal tibia resection height boundary until the coronal angle of the patient's tibia falls within the surgeon's preferred tibial varus / valgus boundary. (5) automatically adjusting the femoral coronal plane alignment; determining an initial distal femoral condyle resection height based on the surgeon's preference and an estimate of cartilage loss; 4. The method of claim 3, comprising iteratively increasing the distal femoral condyle resection height until the medial extension gap is equal to the lateral extension gap while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundary and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundary.

[0131] (6) automatically adjusting the femoral flexion, iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundaries until a total flexion gap equals an ideal flexion gap, wherein the total flexion gap comprises the sum of a lateral flexion gap and a medial flexion gap, and the ideal flexion gap comprises the sum of natural joint laxity in flexion and a predetermined component height; The method of embodiment 3, comprising iteratively adjusting the femoral component anterior / posterior shift in response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary while the posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary until the total flexion gap is equal to the ideal flexion gap. (7) automatically adjusting the femoral flexion, determining a difference between the total flexion gap and the ideal flexion gap in response to the posterior femoral condyle resection height reaching the posterior femoral condyle resection height boundary; determining whether the difference is greater than a predetermined length, the predetermined length being associated with a femoral component size difference; prompting a change to the size of the femoral component in response to determining that the difference is greater than the predetermined length; and in response to determining that the difference is not greater than the predetermined length, iteratively adjusting the proximal tibia resection height while the proximal tibia resection height is within a proximal tibia resection height boundary until the difference reaches the predetermined length; The method of embodiment 6, further comprising resetting the femoral component flexion / extension angle and the femoral component anterior / posterior shift in response to changes in the size of the femoral component or repeated adjustments to the proximal tibia resection height. (8) when the total flexion gap is greater than the ideal flexion gap, (i) iteratively adjusting the femoral component flexion / extension angle includes increasing the femoral component flexion angle, (ii) iteratively adjusting the femoral component anterior / posterior shift includes increasing posteriorization of the femoral component, (iii) prompting a change to the size of the femoral component includes prompting an increase in the size of the femoral component, and (iv) iteratively adjusting the proximal tibial resection height includes decreasing the proximal tibial resection height; The method of embodiment 7, wherein when the total flexion gap is smaller than the ideal flexion gap, (i) iteratively adjusting the femoral component flexion / extension angle comprises decreasing the femoral component flexion angle, (ii) iteratively adjusting the femoral component anterior / posterior shift comprises increasing the anteriorization of the femoral component, (iii) encouraging a change to the size of the femoral component comprises encouraging a decrease in the size of the femoral component, and (iv) iteratively adjusting the proximal tibial resection height comprises increasing the proximal tibial resection height. (9) The method of embodiment 3, wherein automatically adjusting the femoral rotation includes iteratively rotating the femoral component while the posterior femoral condyle resection height is within the posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to the target medial and lateral flexion gaps, respectively. (10) The method of embodiment 3, wherein automatically adjusting the distal femoral condyle resection height comprises iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within a distal femoral condyle resection height boundary until the total extension gap is equal to the total flexion gap.

[0132] (11) An orthopedic surgery planning system, comprising: 1. A computer system comprising: receiving a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of the orthopaedic surgical procedure; acquiring alignment data for a patient's knee joint, the alignment data defining a flexion gap of the knee joint and an extension gap of the knee joint; 1. An orthopaedic surgical planning system comprising: a computer system configured to: determine a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences and the alignment data, the surgical plan including planned values ​​associated with the surgical parameters of the orthopaedic surgical procedure, the planned values ​​being within the one or more boundary values ​​associated with the surgical parameters. (12) The system of embodiment 11, further comprising a registration tool configured to be positioned relative to a plurality of anatomical landmarks of the patient while being observed by the computer system to obtain the registration data. (13) The system of embodiment 11, further comprising a robotic surgical device configured to position a cutting tool to resect bone of the patient to achieve the planned value of the surgical plan. (14) The computer system presenting the surgical plan to a user; receiving, in response to presenting the surgical plan, a modification to the surgical plan, the modification including updated boundary values ​​associated with the surgical parameters; The system of embodiment 11, further configured to determine an updated surgical plan for the orthopedic surgical procedure based on the preferences of the plurality of surgeons, the alignment data, and the updated boundary values, wherein the updated boundary values ​​override at least one of the preferences of the plurality of surgeons. (15) The computer system automatically adjusting the tibial coronal alignment; automatically adjusting a femoral coronal alignment in response to automatically adjusting the tibial coronal alignment; automatically adjusting femoral flexion in response to automatically adjusting the femoral coronal alignment; automatically adjusting femoral rotation in response to automatically adjusting the femoral flexion; and The system of claim 11, wherein the system is configured to determine the surgical plan for the orthopedic surgical procedure by automatically adjusting a distal femoral condyle resection height in response to automatically adjusting the femoral rotation.

[0133] (16) The computer system determining an initial proximal tibial resection height based on the surgeon's preference and an estimate of cartilage loss; The system of embodiment 15, wherein the system is configured to automatically adjust the tibial coronal alignment by iteratively decreasing the proximal tibial resection height while the proximal tibial resection height is within the surgeon's preferred minimum proximal tibial resection height boundary until the coronal angle of the patient's tibia falls within the surgeon's preferred tibial varus / valgus boundary. (17) The computer system determining an initial distal femoral condyle resection height based on the surgeon's preference and an estimate of cartilage loss; The system of embodiment 15, configured to automatically adjust the femoral coronal plane alignment by iteratively increasing the distal femoral condyle resection height while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundary and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundary, until the medial extension gap is equal to the lateral extension gap. (18) The computer system iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundaries until a total flexion gap equals an ideal flexion gap, wherein the total flexion gap comprises the sum of a lateral flexion gap and a medial flexion gap, and the ideal flexion gap comprises the sum of natural joint laxity in flexion and a predetermined component height; The system of embodiment 15, wherein the system is configured to automatically adjust the femoral flexion by iteratively adjusting the femoral component anterior / posterior shift in response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary until the total flexion gap is equal to the ideal flexion gap while the posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary. (19) The system of embodiment 15, wherein the computer system is configured to automatically adjust the femoral rotation by iteratively rotating the femoral component while the posterior femoral condyle resection height is within the posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to the target medial and lateral flexion gaps, respectively. (20) The system of embodiment 15, wherein the computer system is configured to automatically adjust the distal femoral condyle resection height by iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within a distal femoral condyle resection height boundary until the total extension gap is equal to the total flexion gap.

Claims

1. 1. An orthopedic surgical planning system comprising:

1. A computer system comprising: receiving a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of the orthopaedic surgical procedure; acquiring alignment data for a patient's knee joint, the alignment data defining a flexion gap of the knee joint and an extension gap of the knee joint; 1. An orthopaedic surgical planning system comprising: a computer system configured to: determine a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences and the alignment data, the surgical plan including planned values ​​associated with the surgical parameters of the orthopaedic surgical procedure, the planned values ​​being within the one or more boundary values ​​associated with the surgical parameters.

2. 10. The system of claim 1, further comprising a registration tool configured to be positioned relative to a plurality of anatomical landmarks of the patient while being viewed by the computer system to obtain the registration data.

3. The system of claim 1 , further comprising a robotic surgical device configured to position a cutting tool to resect bone of the patient to achieve the planned values ​​of the surgical plan.

4. the computer system, presenting the surgical plan to a user; receiving, in response to presenting the surgical plan, a modification to the surgical plan, the modification including updated boundary values ​​associated with the surgical parameters; 10. The system of claim 1, further configured to: determine an updated surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the registration data, and the updated boundary values, wherein the updated boundary values ​​override at least one of the plurality of surgeon preferences.

5. the computer system, automatically adjusting the tibial coronal alignment; automatically adjusting a femoral coronal alignment in response to automatically adjusting the tibial coronal alignment; automatically adjusting femoral flexion in response to automatically adjusting the femoral coronal alignment; automatically adjusting femoral rotation in response to automatically adjusting the femoral flexion; and 10. The system of claim 1, configured to determine the surgical plan for the orthopaedic surgical procedure by: automatically adjusting a distal femoral condyle resection height in response to automatically adjusting the femoral rotation.

6. the computer system, determining an initial proximal tibial resection height based on the surgeon's preference and an estimate of cartilage loss; 6. The system of claim 5, wherein the system is configured to automatically adjust the tibial coronal alignment by iteratively decreasing the proximal tibial resection height while the proximal tibial resection height remains within the surgeon's preferred minimum proximal tibial resection height boundary until the patient's tibia coronal angle falls within the surgeon's preferred tibial varus / valgus boundary.

7. the computer system, determining an initial distal femoral condyle resection height based on the surgeon's preference and an estimate of cartilage loss; 6. The system of claim 5, wherein the system is configured to automatically adjust the femoral coronal alignment by iteratively increasing the distal femoral condyle resection height while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundaries and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundaries until a medial extension gap equals a lateral extension gap.

8. the computer system, iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundaries until a total flexion gap equals an ideal flexion gap, wherein the total flexion gap comprises the sum of a lateral flexion gap and a medial flexion gap, and the ideal flexion gap comprises the sum of natural joint laxity in flexion and a predetermined component height; 6. The system of claim 5, wherein the system is configured to automatically adjust the femoral flexion by iteratively adjusting a femoral component anterior / posterior shift in response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary until the total flexion gap is equal to the ideal flexion gap while a posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary.

9. 6. The system of claim 5, wherein the computer system is configured to automatically adjust the femoral rotation by iteratively rotating the femoral component while a posterior femoral condyle resection height is within a posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to target medial and lateral flexion gaps, respectively.

10. 6. The system of claim 5, wherein the computer system is configured to automatically adjust the distal femoral condyle resection height by iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within distal femoral condyle resection height boundaries until a total extension gap equals a total flexion gap.

11. 1. A method for generating a surgical plan for an orthopedic surgical procedure, comprising: receiving, by a computer system, a plurality of surgeon preferences including target values ​​and one or more boundary values ​​associated with surgical parameters of the orthopaedic surgical procedure; performing a bony registration of the patient's bony anatomy using the computer system; performing a leg alignment registration of the patient with the computer system, the leg alignment registration including measuring a flexion gap of the patient's knee joint and measuring an extension gap of the patient's knee joint; determining, by the computer system, a surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the bone alignment, and the leg alignment alignment, wherein the surgical plan includes planned values ​​associated with the surgical parameters of the orthopaedic surgical procedure, and the planned values ​​are within the one or more boundary values ​​associated with the surgical parameters.

12. presenting the surgical plan to a user by the computer system; receiving, by the computer system, modifications to the surgical plan in response to presenting the surgical plan, the modifications including updated boundary values ​​associated with the surgical parameters; 12. The method of claim 11, further comprising determining, by the computer system, an updated surgical plan for the orthopaedic surgical procedure based on the plurality of surgeon preferences, the bone alignment, the leg alignment registration, and the updated boundary values, wherein the updated boundary values ​​override at least one of the plurality of surgeon preferences.

13. determining the surgical plan for the orthopaedic surgical procedure; automatically adjusting the tibial coronal alignment; automatically adjusting a femoral coronal alignment in response to automatically adjusting the tibial coronal alignment; automatically adjusting femoral flexion in response to automatically adjusting the femoral coronal alignment; automatically adjusting femoral rotation in response to automatically adjusting the femoral flexion; and and automatically adjusting a distal femoral condyle resection height in response to automatically adjusting the femoral rotation.

14. automatically adjusting the tibial coronal alignment; determining an initial proximal tibial resection height based on the surgeon's preference and an estimate of cartilage loss; 14. The method of claim 13, comprising iteratively decreasing the proximal tibia resection height while the proximal tibia resection height is within the surgeon's preferred minimum proximal tibia resection height boundary until the coronal angle of the patient's tibia is within the surgeon's preferred tibial varus / valgus boundary.

15. automatically adjusting the femoral coronal alignment; determining an initial distal femoral condyle resection height based on the surgeon's preference and an estimate of cartilage loss; 14. The method of claim 13, comprising iteratively increasing the distal femoral condyle resection height while the coronal angle of the patient's femur is within the surgeon's preferred femoral varus / valgus boundaries and while the distal femoral condyle resection height is within the surgeon's preferred maximum distal femoral condyle resection height boundaries until a medial extension gap equals a lateral extension gap.

16. automatically adjusting the femoral flexion; iteratively adjusting the femoral component flexion / extension angle while the femoral component flexion / extension angle is within the surgeon's preferred femoral component flexion / extension boundaries until a total flexion gap equals an ideal flexion gap, wherein the total flexion gap comprises the sum of a lateral flexion gap and a medial flexion gap, and the ideal flexion gap comprises the sum of natural joint laxity in flexion and a predetermined component height; 14. The method of claim 13, comprising: in response to the femoral component flexion / extension angle reaching the femoral component flexion / extension boundary, iteratively adjusting a femoral component anterior / posterior shift while a posterior femoral condyle resection height is within the surgeon's preferred posterior femoral condyle resection height boundary until the total flexion gap is equal to the ideal flexion gap.

17. automatically adjusting the femoral flexion; determining a difference between the total flexion gap and the ideal flexion gap in response to the posterior femoral condyle resection height reaching the posterior femoral condyle resection height boundary; determining whether the difference is greater than a predetermined length, the predetermined length being associated with a femoral component size difference; prompting a change to the size of the femoral component in response to determining that the difference is greater than the predetermined length; and in response to determining that the difference is not greater than the predetermined length, iteratively adjusting the proximal tibia resection height while the proximal tibia resection height is within a proximal tibia resection height boundary until the difference reaches the predetermined length; 17. The method of claim 16, further comprising resetting the femoral component flexion / extension angle and the femoral component anterior / posterior shift in response to changes in the size of the femoral component or iterative adjustments to the proximal tibia resection height.

18. When the total flexion gap is greater than the ideal flexion gap, (i) iteratively adjusting the femoral component flexion / extension angle comprises increasing the femoral component flexion angle, (ii) iteratively adjusting the femoral component anterior / posterior shift comprises increasing posteriorization of the femoral component, (iii) prompting a change to the size of the femoral component comprises prompting an increase in the size of the femoral component, and (iv) iteratively adjusting the proximal tibial resection height comprises decreasing the proximal tibial resection height.

18. The method of claim 17, wherein when the total flexion gap is less than the ideal flexion gap, (i) iteratively adjusting the femoral component flexion / extension angle comprises decreasing the femoral component flexion angle, (ii) iteratively adjusting the femoral component anterior / posterior shift comprises increasing anteriorization of the femoral component, (iii) prompting a change to the size of the femoral component comprises prompting a decrease in the size of the femoral component, and (iv) iteratively adjusting the proximal tibial resection height comprises increasing the proximal tibial resection height.

19. 14. The method of claim 13, wherein automatically adjusting the femoral rotation comprises iteratively rotating the femoral component while a posterior femoral condyle resection height is within a posterior femoral condyle resection height boundary until the medial and lateral flexion gaps are equal to target medial and lateral flexion gaps, respectively.

20. 14. The method of claim 13, wherein automatically adjusting the distal femoral condyle resection height comprises iteratively adjusting the distal femoral condyle resection height while the distal femoral condyle resection height is within a distal femoral condyle resection height boundary until a total extension gap equals a total flexion gap.

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