Calculation method of lower extremity force line angle in total knee arthroplasty
By establishing a matrix transformation of the skeletal and prosthesis coordinate systems during total knee arthroplasty, and using the condylar-oppositional fossa position as a transformation constraint, the problem of quantitative calculation of lower limb force line angles was solved, enabling precise adjustment of prosthesis placement and improving surgical outcomes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING TINAVI MEDICAL TECH
- Filing Date
- 2021-12-31
- Publication Date
- 2026-07-03
Smart Images
Figure CN116421368B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of medical devices, specifically to a method, apparatus, electronic device, and computer-readable storage medium for calculating the lower limb force line angle in total knee arthroplasty. Background Technology
[0002] Total knee arthroplasty (TKA) is a new technique for treating knee joint diseases. By replacing the joint surfaces of the knee joint with prosthetic components, it can effectively eliminate severe knee pain and greatly improve the quality of life for patients. For TKA, proper placement of the prosthesis according to the lower limb alignment is crucial for surgical success. On the one hand, improper prosthesis placement and failure to maintain normal lower limb alignment can lead to symptoms such as pain, limited joint mobility, loosening, wear and tear, and joint instability, affecting the surgical outcome. On the other hand, the lifespan of a TKA largely depends on the postoperative lower limb alignment.
[0003] The most commonly used indicator for evaluating lower limb alignment is the coronal plane lower limb alignment, usually expressed as the HKA angle (Hip-Knee-Ankle angle). The common method for measuring the HKA angle is as follows: On a standard full-length weight-bearing X-ray of the lower limb, determine the centers of the femoral head, knee joint, and ankle joint; define the line connecting the centers of the femoral head and knee joint as the femoral mechanical axis, and the line connecting the centers of the ankle and knee joint as the tibial mechanical axis. The angle between the femoral mechanical axis and the tibial mechanical axis is the HKA angle. The generally accepted target HKA angle for lower limb alignment after knee replacement surgery is within ±3 degrees.
[0004] Currently, the lower limb alignment angle (HKA) is mostly measured post-operatively and can only be used to assess surgical outcomes, not to guide surgical planning. In traditional total knee replacement surgery, the lower limb alignment angle is estimated by the placement of the prosthesis or by installing a trial mold after osteotomy. This relies entirely on the surgeon's experience for qualitative analysis, lacking quantitative results and making it difficult to guarantee the post-operative lower limb alignment angle. Summary of the Invention
[0005] To address the lack of quantitative calculation of lower limb alignment angles in existing total knee arthroplasty procedures, this application provides a method for calculating lower limb alignment angles in total knee arthroplasty. The calculation method includes:
[0006] Transform the first skeletal mechanical axis at its initial position in the image coordinate system to the defined first prosthesis coordinate system;
[0007] When the first bone mechanical axis in the first prosthesis coordinate system rotates with the first prosthesis to the position of the condyle under load, the first bone mechanical axis is transformed to the second prosthesis coordinate system;
[0008] Transform the first bone mechanical axis in the second prosthesis coordinate system to the image coordinate system;
[0009] The angle between the first skeletal mechanical axis and the second skeletal mechanical axis is projected onto the coronal plane to obtain the lower limb force line angle.
[0010] According to some embodiments of this application, transforming the first skeletal mechanical axis at its initial position in the image coordinate system to a defined first prosthesis coordinate system includes:
[0011] Coordinate transformation is performed based on the first coordinate system transformation matrix and the first spur pose adjustment matrix; wherein...
[0012] The first coordinate system transformation matrix is the transformation matrix from the image coordinate system to the first spur coordinate system at the initial position;
[0013] The first prosthesis pose adjustment matrix is the transformation matrix of the first prosthesis from its initial position to its adjusted position.
[0014] According to some embodiments of this application, transforming the first skeletal mechanical axis in the second prosthesis coordinate system to the image coordinate system includes:
[0015] Coordinate transformation is performed based on the second coordinate system transformation matrix and the second prosthetic pose adjustment matrix; where...
[0016] The second coordinate system transformation matrix is the transformation matrix from the image coordinate system to the second spur coordinate system at the initial position;
[0017] The second prosthesis pose adjustment matrix is the transformation matrix of the second prosthesis from its initial position to its adjusted position.
[0018] According to some embodiments of this application, the first bone is the tibia, the first prosthesis is a tibial prosthesis, the second bone is the femur, and the second prosthesis is a femoral prosthesis; or
[0019] The first bone is the femur, the first prosthesis is a femoral prosthesis, the second bone is the tibia, and the second prosthesis is a tibial prosthesis.
[0020] According to some embodiments of this application, during the transformation process, the first bone and the first prosthesis maintain a rigid connection; during the transformation process, the second bone and the second prosthesis maintain a rigid connection.
[0021] According to some embodiments of this application, the calculation method further includes:
[0022] The calculation method is performed according to the poses of the first and second prostheses after adjustment based on the lower limb force line angle, to recalculate the lower limb force line angle.
[0023] According to another aspect of this application, a calculation device for the lower limb force line angle during total knee arthroplasty is also provided, the calculation device comprising:
[0024] The first transformation module is used to transform the first skeletal mechanical axis at its initial position in the image coordinate system to the defined first prosthesis coordinate system.
[0025] The second transformation module is used to transform the first bone mechanical axis in the first prosthesis coordinate system to the second prosthesis coordinate system when the first bone mechanical axis rotates with the first prosthesis to the position of the condyle under load.
[0026] The third transformation module is used to transform the first bone mechanical axis in the second prosthesis coordinate system to the image coordinate system;
[0027] The fourth transformation module is used to project the angle between the first skeletal mechanical axis and the second skeletal mechanical axis onto the coronal plane to obtain the lower limb force line angle.
[0028] According to some embodiments of this application, the computing device further includes:
[0029] The iterative correction module is used to recalculate the lower limb force line angle based on the poses of the first prosthesis and the second prosthesis after adjustment guided by the lower limb force line angle.
[0030] According to another aspect of this application, an electronic device for calculating the lower limb force line angle during total knee arthroplasty is also provided, comprising:
[0031] One or more processors;
[0032] Storage device for storing one or more programs;
[0033] When the one or more programs are executed by the one or more processors, the one or more processors perform the above-described calculation method.
[0034] According to another aspect of this application, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed by a processor, implements the above-described calculation method.
[0035] The method for calculating the lower limb alignment angle during total knee arthroplasty provided in this application uses the condylar notch position as a transformation constraint. Through matrix transformation between the established skeletal coordinate system and the prosthesis coordinate system, the HKA angle is calculated intraoperatively, providing more accurate quantitative calculation results for total knee arthroplasty. Furthermore, based on the quantitative calculation results, the surgeon can adjust the prosthesis placement position in a timely manner during surgery; the adjusted HKA angle can be recalculated based on the adjusted prosthesis position, thus obtaining the optimal prosthesis placement position through continuous iteration, ensuring postoperative outcomes. Attached Figure Description
[0036] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings, without exceeding the scope of protection claimed by this application.
[0037] Figure 1 This illustration shows the HKA angle calculation principle according to an example embodiment of this application. Figure 1 ;
[0038] Figure 2 This illustration shows the HKA angle calculation principle according to an example embodiment of this application. Figure 2 ;
[0039] Figure 3 A schematic diagram of the femoral coordinate system according to an example embodiment of this application is shown;
[0040] Figure 4 A schematic diagram of the tibial coordinate system according to an example embodiment of this application is shown;
[0041] Figure 5 A schematic diagram showing the position of the prosthesis's "condyle-opposition socket" in a non-weight-bearing state according to an example embodiment of this application;
[0042] Figure 6 This diagram illustrates the non-weight-bearing prosthesis adjustment position according to an example embodiment of this application.
[0043] Figure 7 A flowchart of a calculation method according to a first exemplary embodiment of this application is shown;
[0044] Figure 8 A flowchart of a calculation method according to a second exemplary embodiment of this application is shown;
[0045] Figure 9 This diagram illustrates a block diagram of a computing device according to a first exemplary embodiment of this application.
[0046] Figure 10This diagram illustrates a block diagram of a computing device according to a second exemplary embodiment of this application.
[0047] Figure 11 This diagram illustrates an electronic device for calculating the lower limb force line angle during total knee arthroplasty according to an example embodiment of this application. Detailed Implementation
[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0049] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a predetermined order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.
[0050] In this document, the term "embodiment" means that a predetermined feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0051] As mentioned above, in order to provide more accurate data guidance for the placement of the prosthesis in total knee arthroplasty, thereby ensuring the postoperative effect of the patient and the normal use of the prosthesis, this application provides a method for calculating the lower limb force line angle in total knee arthroplasty. Based on the adjustment of the prosthesis position during the operation, the lower limb force line angle can be quickly estimated, providing a quantitative basis for adjusting the surgical plan.
[0052] Figure 1 This illustration shows the HKA angle calculation principle according to an example embodiment of this application. Figure 1 ; Figure 2 This illustration shows the HKA angle calculation principle according to an example embodiment of this application. Figure 2 .
[0053] The method for calculating the lower limb force line angle provided in this application is based on Figure 1 and Figure 2The calculation principle is shown below. Figure 1 As shown, during the intraoperative planning of total knee arthroplasty, the femur and tibia are positioned in the condylar notch in a non-weight-bearing position in the preoperative planning data package. Femoral mechanical axis l FB Tibial mechanical axis TB They are usually not on a straight line. Figure 1 Mid-femoral mechanical axis L FB Tibial mechanical axis TB On a straight line, merely for illustrative purposes. Femoral mechanical axis l FB Tibial mechanical axis TB Whether the components are collinear or not does not affect the technical solution of this application. Femoral prosthesis l F Tibial prosthesis T The initial position is used. Since the data in the preoperative planning reflects the patient's preoperative condition, the prosthesis position usually needs to be adjusted based on the patient's actual condition. See also... Figure 1 femoral prosthesis FP Tibial prosthesis L TP This is the position of the implant after adjustment.
[0054] Since the lower limb force line angle is the HKA angle when the patient is bearing weight, it is necessary to convert the femur, femoral prosthesis, tibia, and tibial prosthesis to a weight-bearing state, so that the femoral and tibial prostheses are in the condylar fossa position, and then calculate the angle between the femoral and tibial mechanical axes. In this process, the planned positions of the femur and femoral prosthesis can be kept unchanged, and the positions of the tibia and tibial prosthesis can be changed to obtain the weight-bearing condylar fossa position; alternatively, the planned positions of the tibia and tibial prosthesis can be kept unchanged, and the positions of the femur and femoral prosthesis can be changed to obtain the weight-bearing condylar fossa position; or the positions of the femur and femoral prosthesis and the tibia and tibial prosthesis can be changed simultaneously, as long as the relative positional changes of the two can be determined. Figure 2 The image shows the maintenance of the femoral mechanical axis L. FB Adjusted femoral prosthesis FP With the position unchanged, the mechanical axis of the tibia is changed. TB Adjusted tibial prosthesis TP The position is determined to obtain the condylar-oppositional fossa position during weight-bearing. During the transition, the tibial prosthesis maintains a rigid connection with the tibia; that is, the tibial prosthesis l TP Connecting the tibial mechanical axis l TB The coordinates are transformed together. After the tibia and tibial prosthesis are transformed together, the mechanical axis of the tibia is represented as L′. Tb The tibial mechanical axis, after being transformed from the tibial prosthesis coordinate system to the femoral prosthesis coordinate system, is represented as follows: The tibial mechanical axis, after being transformed from the femoral prosthesis coordinate system to the image coordinate system, is represented as follows: At this point, the tibial mechanical axis can be used. With femoral mechanical axis l FB The angle α between them is used to obtain the HKA angle.
[0055] Figure 3 A schematic diagram of the femoral coordinate system according to an example embodiment of this application is shown; Figure 4 A schematic diagram of the tibial coordinate system according to an example embodiment of this application is shown.
[0056] The above transformation process requires a series of transformation matrices during calculation. These transformation matrices can be determined by the relationships between the corresponding coordinate systems. For example... Figure 3 As shown, according to an example embodiment of this application, a femoral coordinate system can be defined in the image coordinate system based on a series of bony feature points on the femur 3 in the image, with the origin o. FB This indicates. For example, see [link to example]. Figure 3 A series of bony features on the femur may include: femoral head center 1, lateral femoral condyle 4, medial femoral condyle 5, and intercondylar fossa center 6. The line connecting femoral head center 1 and intercondylar fossa center 6 is the femoral mechanical axis 2. Femoral coordinate system o FB The establishment process is as follows: the origin is the midpoint of the line connecting the lateral femoral condyle 4 and the medial femoral condyle 5. FB ; with the direction of the femoral mechanical axis 2 as z FB axis; z FB Multiply the axis by the line connecting the lateral femoral condyle 4 and the medial femoral condyle 5 to obtain y. FB axis; z FB axis and y FB The cross product of axes yields x FB Axis. In the femoral coordinate system o PB Below, x FB o FB z FB The plane is coronal, x FB o FB y FB The surface is a cross-section, y FB o FB z FB The plane is the sagittal plane. Femoral coordinate system o FB Once established, the image coordinate system can be converted to the femoral coordinate system. FB The transformation matrix T of the femoral coordinate system F1 .
[0057] Similarly, see Figure 4 A tibial coordinate system can be defined in the image coordinate system based on a series of bony feature points on the tibia 11, with the origin O. TB This indicates. For example, see [link to example]. Figure 4A series of bony features on the tibia 11 may include: the lowest point 7 on the posterior side of the tibial plateau, the center of the tibial intercondylar crest 8, the medial third of the tibial tuberosity 9, the lateral tibial malleolus 12, and the medial tibial malleolus 13. The line connecting the midpoint of the line connecting the lateral tibial malleolus 12 and the medial tibial malleolus 13 to the center 8 of the tibial intercondylar crest is the tibial mechanical axis 10. The line connecting the medial third of the tibial tuberosity 9 to the lowest point 7 on the posterior side of the tibial plateau is the tibial Akagi line. Tibial coordinate system O TB The establishment process is as follows: with the center of the intercondylar crest of the tibia as the origin O. TB ; with the tibial mechanical axis 10 as z TB axis; z TB x is obtained by multiplying the axis by the Akagi line of the tibia. TB axis; z TB axis and x TB The cross product of axes yields y TB Axis. Tibial coordinate system O TB Once established, the image coordinate system can be converted to the tibial coordinate system O. TB Tibial coordinate system transformation matrix T T1 .
[0058] Figure 5 This diagram illustrates the position of the prosthesis's "condylar socket" in a non-weight-bearing state according to an example embodiment of this application.
[0059] During intraoperative planning, the initial positions of the femur and tibia are in the condylar fossa position in a non-weight-bearing state, such as... Figure 5 As shown, the normal direction of the distal osteotomy surface of the femoral prosthesis 14 (i.e., perpendicular to the distal osteotomy surface of the femur) is taken as the normal direction of the femoral prosthesis 14, and the femoral prosthesis 14 is placed on the femur 3 to form a rigid connection. At this time, in the initial position of the femoral prosthesis 14, the normal direction of the femoral prosthesis 14 coincides with the mechanical axis of the femur. Thus, a femoral prosthesis coordinate system O can be established. F The directions of each coordinate axis are relative to the femoral coordinate system. FB Consistent.
[0060] Similarly, taking the normal direction of the tibial prosthesis osteotomy surface (i.e., perpendicular to the tibial osteotomy surface) as the normal direction of the tibial prosthesis 15, the tibial prosthesis 15 is placed on the tibia 11, maintaining a rigid connection during the transformation process. At this point, in the initial position of the tibial prosthesis 15, the normal direction of the tibial prosthesis 15 coincides with the mechanical axis of the tibia. Therefore, a tibial prosthesis coordinate system O can be established. T The directions of each coordinate axis are relative to the femoral coordinate system O. TB Consistent.
[0061] Figure 6 This diagram illustrates the positional adjustment of the prosthesis under non-load conditions according to an example embodiment of this application.
[0062] During surgical planning, the initial positions of the femoral and tibial prostheses are determined based on the patient's preoperative data. Typically, these preoperative data need to be corrected surgically; that is, the initial positions of the prostheses are usually adjusted during surgery based on the patient's actual condition. The adjusted positions of the femoral prosthesis 14 and tibial prosthesis 15 are shown below. Figure 6 As shown. At this time, the femoral prosthesis coordinate system O F No longer in the femoral coordinate system FB Consistent direction; Tibial prosthesis coordinate system O T No longer in tibial coordinate system O TB Consistent. Based on the adjusted position of the prosthesis, the femoral prosthesis pose adjustment matrix T from the femoral coordinate system to the adjusted femoral prosthesis coordinate system can be determined. F2 And the tibial prosthesis pose adjustment matrix T from the tibial coordinate system to the adjusted tibial prosthesis coordinate system. T2 .
[0063] Figure 7 A block diagram illustrating the composition of a calculation method according to a first exemplary embodiment of this application is shown.
[0064] Based on the above calculation principle and the determined femoral coordinate system transformation matrix T F1 1. Tibial coordinate system transformation matrix T T1 Femoral prosthesis pose adjustment matrix T F2 Tibial prosthesis pose adjustment matrix T T2 By performing a series of coordinate transformations, the angle between the femoral mechanical axis and the tibial mechanical axis in the weight-bearing position can be calculated in the image coordinate system, thus obtaining the HKA angle.
[0065] like Figure 7 As shown, the method for calculating the lower limb force line angle in total knee arthroplasty provided in this application includes the following steps:
[0066] Step S110: Transform the first skeletal mechanical axis at the initial position in the image coordinate system to the defined first prosthesis coordinate system. This coordinate transformation can be performed using a first coordinate system transformation matrix and a first prosthesis pose adjustment matrix. The first coordinate system transformation matrix is the transformation matrix from the image coordinate system to the first prosthesis coordinate system at the initial position; the first prosthesis pose adjustment matrix is the transformation matrix of the first prosthesis from its initial position to its adjusted position.
[0067] According to some embodiments of this application, the first bone may be the tibia, the mechanical axis of the first bone may be the tibial mechanical axis, and the first prosthesis may be a tibial prosthesis. According to other embodiments of this application, the first bone may be the femur, the mechanical axis of the first bone may be the femoral mechanical axis, and the first prosthesis may be a femoral prosthesis. Regardless of whether the first femur is the tibia or the femur, the calculation principle is the same. In this application, the tibia is used as the first bone, but it is not limited thereto.
[0068] When the first bone is the tibia, the transformation matrix of the first coordinate system is the tibial coordinate system transformation matrix T. T1 The first prosthesis pose adjustment matrix is the tibial prosthesis pose adjustment matrix T. T2 Therefore, the mechanical axis of the tibia in the image coordinate system is l TB The tibial prosthesis coordinate system is obtained by the following transformation: o T Below, represented as l TB :
[0069] l TB =(T T1 T T2 ) -1 l TB .
[0070] In step S120, when the first bone mechanical axis in the first prosthesis coordinate system rotates with the first prosthesis to the position of the condyle under load, the first bone mechanical axis is transformed to the second prosthesis coordinate system.
[0071] As shown above, when the first bone is the tibia, the first prosthesis is a tibial prosthesis, and the second prosthesis is a femoral prosthesis. Figure 2 As shown, during the transformation process, the tibial prosthesis maintains a rigid connection with the tibia. During the rotation to the weight-bearing condylar fossa position, the tibial mechanical axis rotates together with the tibial prosthesis; the tibial mechanical axis is still represented by l′. TB .
[0072] The first skeletal mechanical axis (tibial mechanical axis) in the second prosthetic coordinate system (femoral coordinate system) can be represented as: When in the condylar fossa position, the tibial prosthesis coordinate system o T coordinates with the femoral prosthesis F If the directions are the same, then:
[0073]
[0074] Step S130: Transform the mechanical axis of the first bone in the second prosthesis coordinate system to the image coordinate system. This coordinate transformation can be performed using the second coordinate system transformation matrix and the second prosthesis pose adjustment matrix. As previously shown, when the first bone is the tibia, the second bone is the femur. The second coordinate system transformation matrix is the femur coordinate system transformation matrix T. F1 The first matrix is the transformation matrix from the image coordinate system to the femoral prosthesis coordinate system at the initial position; the second prosthesis pose adjustment matrix is the femoral prosthesis pose adjustment matrix T. F2 That is, the transformation matrix of the femoral prosthesis from its initial position to its adjusted position.
[0075] Step S120 yielded the representation of the tibial mechanical axis in the femoral coordinate system. Assume the mechanical axis of the tibia is represented in the image coordinate system as follows: Through the second coordinate system transformation matrix (femoral coordinate system transformation matrix T) F1 ), second prosthesis pose adjustment matrix (femoral prosthesis pose adjustment matrix T) F2 The mechanical axis of the tibia in the image coordinate system can be obtained according to the following formula:
[0076]
[0077] Step S140: Project the angle between the first and second skeletal mechanical axes onto the coronal plane to obtain the lower limb force line angle. The tibial mechanical axis can be calculated within the same image coordinate system. With femoral mechanical axis l FB The included angle α between them is projected onto the coronal plane. Figure 3 The plane x shown FB o FB z FB This will give you the lower limb force line angle (HKA angle).
[0078] Figure 8 A block diagram illustrating the composition of a calculation method according to a second exemplary embodiment of this application is shown.
[0079] like Figure 8 As shown, according to another embodiment of this application, the method for calculating the lower limb force line angle in total knee arthroplasty further includes:
[0080] Step S150: Based on the positions of the first and second prostheses adjusted according to the lower limb force line angle, execute... Figure 7 The calculation method described herein involves recalculating the lower limb force line angle. The calculated lower limb force line angle is typically used as the basis for further pose adjustments to the prosthesis. After further adjustments to the prosthesis based on the calculated lower limb force line angle, the adjusted lower limb force line angle can be recalculated through steps S110 to S150, and the calculation can be iteratively performed continuously.
[0081] Figure 9 A block diagram of a computing device according to a first exemplary embodiment of this application is shown.
[0082] According to another aspect of this application, a device for calculating the lower limb alignment angle in total knee arthroplasty is also provided. Figure 9 As shown, the computing device 100 includes a first transformation module 110, a second transformation module 120, a third transformation module 130, and a fourth transformation module 140.
[0083] The first transformation module 110 can be used to transform the first skeletal mechanical axis at its initial position in the image coordinate system to the defined first prosthesis coordinate system.
[0084] The second transformation module 120 can be used to transform the first skeletal mechanical axis in the first prosthesis coordinate system to the second prosthesis coordinate system when the first skeletal mechanical axis rotates with the first prosthesis to the position of the condyle under load.
[0085] The third transformation module 130 can be used to transform the first bone mechanical axis in the second prosthesis coordinate system to the image coordinate system.
[0086] The fourth transformation module 140 can be used to project the angle between the first skeletal mechanical axis and the second skeletal mechanical axis onto the coronal plane to obtain the lower limb force line angle.
[0087] Figure 10 A block diagram of a computing device according to a second exemplary embodiment of this application is shown.
[0088] like Figure 10 As shown, according to another embodiment of this application, the calculation device 100 for the lower limb force line angle in total knee arthroplasty further includes an iterative correction module 150, which can be used to recalculate the lower limb force line angle based on the poses of the first prosthesis and the second prosthesis after adjustment guided by the lower limb force line angle.
[0089] Figure 11 This diagram illustrates an electronic device for calculating the lower limb force line angle in total knee arthroplasty according to an example embodiment of this application.
[0090] This application also provides an electronic device 800 for calculating the lower limb force line angle in total knee arthroplasty. Figure 11 The electronic device 800 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.
[0091] like Figure 11 As shown, the electronic device 800 is presented in the form of a general-purpose computing device. The components of the electronic device 800 may include, but are not limited to: at least one processing unit 810, at least one storage unit 820, and a bus 830 connecting different system components (including the storage unit 820 and the processing unit 810).
[0092] The storage unit 820 stores program code, which can be executed by the processing unit 810, causing the processing unit 810 to perform the method for calculating the lower limb force line angle in total knee arthroplasty according to the embodiments of this application as described in this specification.
[0093] Storage unit 820 may include a readable medium in the form of a volatile storage unit, such as random access memory (RAM) 8201 and / or cache memory 8202, and may further include a read-only memory (ROM) 8203.
[0094] The storage unit 820 may also include a program / utility 8204 having a set (at least one) of program modules 8205, including but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.
[0095] Bus 830 can represent one or more of several types of bus structures, including a memory cell bus or memory cell controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of the various bus structures.
[0096] Electronic device 800 can also communicate with one or more external devices 8001 (e.g., touchscreen, keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 800, and / or with any device that enables electronic device 800 to communicate with one or more other computing devices (e.g., router, modem, etc.). This communication can be performed via input / output (I / O) interface 850. Furthermore, electronic device 800 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 860. Network adapter 860 can communicate with other modules of electronic device 800 via bus 830. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 800, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.
[0097] This application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method for calculating and registering the lower limb force line angle in total knee arthroplasty.
[0098] The method for calculating the lower limb alignment angle during total knee arthroplasty provided in this application uses the condylar notch position as a transformation constraint. Through matrix transformation between the established skeletal coordinate system and the prosthesis coordinate system, the HKA angle is calculated intraoperatively, providing more accurate quantitative calculation results for total knee arthroplasty. Furthermore, based on the quantitative calculation results, the surgeon can adjust the prosthesis placement position in a timely manner during surgery; the adjusted HKA angle can be recalculated based on the adjusted prosthesis position, thus obtaining the optimal prosthesis placement position through continuous iteration, ensuring postoperative outcomes.
[0099] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. Furthermore, any changes or modifications made by those skilled in the art based on the ideas of this application, and on the specific implementation methods and application scope of this application, are all within the scope of protection of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for calculating a lower extremity mechanical axis angle in total knee arthroplasty, characterized by, include: The first skeletal mechanical axis at its initial position in the image coordinate system is transformed to a defined first prosthesis coordinate system. The transformation includes coordinate transformation based on a first coordinate system transformation matrix and a first prosthesis pose adjustment matrix. The first coordinate system transformation matrix is the transformation matrix from the image coordinate system to the first prosthesis coordinate system at the initial position. The first prosthesis pose adjustment matrix is the transformation matrix of the first prosthesis from its initial position to its adjusted position. When the first bone mechanical axis in the first prosthesis coordinate system rotates with the first prosthesis to the position of the condyle under load, the first bone mechanical axis is transformed to the second prosthesis coordinate system; The first skeletal mechanical axis in the second prosthesis coordinate system is transformed to the image coordinate system. The transformation includes coordinate transformation based on the second coordinate system transformation matrix and the second prosthesis pose adjustment matrix. The second coordinate system transformation matrix is the transformation matrix from the image coordinate system to the second prosthesis coordinate system at the initial position. The second prosthesis pose adjustment matrix is the transformation matrix of the second prosthesis from the initial position to the adjusted position. The angle between the first and second skeletal mechanical axes is projected onto the coronal plane to obtain the lower limb force line angle.
2. The calculation method according to claim 1, characterized in that, The first bone is the tibia, the first prosthesis is a tibial prosthesis, the second bone is the femur, and the second prosthesis is a femoral prosthesis; or The first bone is the femur, the first prosthesis is a femoral prosthesis, the second bone is the tibia, and the second prosthesis is a tibial prosthesis.
3. The calculation method according to claim 1, characterized in that, During the transformation process, the first bone and the first prosthesis maintain a rigid connection; During the transformation process, the second bone and the second prosthesis remain rigidly connected.
4. The computational method of claim 1, wherein, Also includes: Based on the positions of the first and second prostheses adjusted according to the lower limb force line angle, the steps of the calculation method of claim 1 are performed to recalculate the lower limb force line angle.
5. A device for calculating a lower extremity mechanical axis angle in total knee arthroplasty, comprising: include: The first transformation module is used to transform the first skeletal mechanical axis at the initial position in the image coordinate system to the defined first prosthesis coordinate system. The transformation includes coordinate transformation based on the first coordinate system transformation matrix and the first prosthesis pose adjustment matrix. The first coordinate system transformation matrix is the transformation matrix from the image coordinate system to the first prosthesis coordinate system at the initial position. The first prosthesis pose adjustment matrix is the transformation matrix of the first prosthesis from the initial position to the adjusted position. The second transformation module is used to transform the first bone mechanical axis in the first prosthesis coordinate system to the second prosthesis coordinate system when the first bone mechanical axis rotates with the first prosthesis to the position of the condyle under load. The third transformation module is used to transform the first skeletal mechanical axis in the second prosthesis coordinate system to the image coordinate system. The transformation includes coordinate transformation based on the second coordinate system transformation matrix and the second prosthesis pose adjustment matrix. The second coordinate system transformation matrix is the transformation matrix from the image coordinate system to the second prosthesis coordinate system at the initial position. The second prosthesis pose adjustment matrix is the transformation matrix of the second prosthesis from the initial position to the adjusted position. The fourth transformation module is used to project the angle between the first skeletal mechanical axis and the second skeletal mechanical axis onto the coronal plane to obtain the lower limb force line angle.
6. The computing device of claim 5, wherein, Also includes: The iterative correction module is used to recalculate the lower limb force line angle based on the poses of the first prosthesis and the second prosthesis after adjustment guided by the lower limb force line angle.
7. An electronic device, characterized in that, include: One or more processors; Storage device for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the computation method according to any one of claims 1-4.
8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the calculation method according to any one of claims 1-4.