Method, device, electronic device, storage medium and program product for determining the insertion direction of elbow joint suture anchor

Abstract

The present disclosure provides a method, device, electronic device, storage medium and program product for determining an insertion direction of a suture anchor in an elbow joint. The method comprises: acquiring three-dimensional image data and suture anchor data of a target patient's elbow joint; constructing a reference three-dimensional coordinate system based on preset anatomical feature points in the three-dimensional image data of the elbow joint; constructing a plurality of elbow joint models with inserted anchors according to the reference three-dimensional coordinate system based on the three-dimensional image data of the elbow joint and the suture anchor data, wherein each elbow joint model with inserted anchors is used to represent that a suture anchor is inserted into the elbow joint of the target patient along a candidate insertion direction; performing mechanical analysis and calculation on each of the elbow joint models with inserted anchors to obtain mechanical information corresponding to each elbow joint model with inserted anchors; and determining one of a plurality of candidate insertion directions corresponding to the elbow joint models with inserted anchors as a preferred insertion direction based on the mechanical information corresponding to each of the elbow joint models with inserted anchors.

Description

Technical Field

[0001] The present disclosure generally relates to the field of biomechanics technology, and more particularly, to a method, device, electronic device, storage medium, and program product for determining an insertion direction of a suture anchor in an elbow joint. Background Art

[0002] Elbow sports injuries are among the most common clinical conditions. Joint and tendon injuries caused by osteoarthritis and tennis elbow can cause pain and limited mobility, severely impacting patients' daily lives. In recent years, arthroscopic surgery has increasingly replaced traditional open surgery due to its minimal invasiveness and rapid recovery. However, arthroscopic elbow surgery presents certain technical bottlenecks, with surgical outcomes heavily dependent on the surgeon's clinical experience and lacking precise preoperative planning. Arthroscopic tendon repair surgery relies on suture anchors to repair injured tendons. During anchor placement, misalignment can lead to the anchor penetrating the cortical bone, dropping out, or entering the joint. Furthermore, anchor failure can also lead to failure of the tendon repair procedure. Causes of anchor failure include loosening, displacement, and pullout, ultimately resulting in articular cartilage damage, pain, and even secondary surgeries. Anchor strength is dependent on factors such as anchor design, patient bone density, and insertion depth and angle. Therefore, determining the optimal anchor placement direction is a key technique in elbow arthroscopic surgery.

[0003] Due to the complex anatomy of the elbow joint and individual differences in humeral structure, the direction of anchor insertion can result in significant differences in mechanical strength and clinical recovery function. However, research on anchor insertion direction is currently lacking. During elbow arthroscopy, the position and direction of anchor insertion are determined entirely by the surgeon's experience. To prevent deviations in the direction of the suture anchor, such as penetrating the cortical bone, detaching from the suture anchor, or entering the joint, repeated fluoroscopy is required, increasing surgical risk and exposing the surgeon to prolonged radiation exposure.

[0004] From the perspective of numerical analysis technology, although the existing finite element modeling technology can establish a finite element model of bone tissue with accurate appearance and similar material properties, for different samples, due to the inconsistency of the human body posture when scanning medical images such as CT (Computed Tomography) and MRI (Magnetic Resonance Imaging), the three-dimensional coordinate system of the scanned image is inconsistent, and the existing technology cannot put different samples into the same coordinate system for comparison. For elbow surgery, if the optimal insertion direction of suture anchors in elbow arthroscopic surgery is studied, the distal humeral coordinate systems of multiple elbow joint images need to be unified to describe the insertion site of the suture anchors. Therefore, realizing a modeling method for a unified distal humeral coordinate system is particularly necessary for achieving accurate preoperative planning of elbow arthroscopic surgery. Summary of the Invention

[0005] The present disclosure provides a method, device, electronic device, storage medium and program product for determining the insertion direction of an elbow joint suture anchor, which are used to solve at least one of the above problems.

[0006] According to a first aspect of an embodiment of the present disclosure, a method for determining an insertion direction of a suture anchor in an elbow joint is provided, the method comprising: acquiring three-dimensional image data and suture anchor data of a target patient's elbow joint; constructing a reference three-dimensional coordinate system based on preset anatomical feature points in the three-dimensional image data of the elbow joint; constructing, based on the three-dimensional image data of the elbow joint and the suture anchor data, a plurality of elbow joint models with inserted anchors according to the reference three-dimensional coordinate system, wherein each elbow joint model with inserted anchors is used to represent inserting a suture anchor into the elbow joint of the target patient along a candidate insertion direction, and the plurality of elbow joint models with inserted anchors correspond one-to-one to the plurality of candidate insertion directions; performing mechanical analysis and calculation on the plurality of elbow joint models with inserted anchors to obtain mechanical information corresponding to each elbow joint model with inserted anchors; and determining, based on the mechanical information corresponding to each of the plurality of elbow joint models with inserted anchors, one of the plurality of candidate insertion directions corresponding to the plurality of elbow joint models with inserted anchors as a preferred insertion direction.

[0007] Optionally, the preset anatomical feature points include the apex of the medial epicondyle, the apex of the lateral epicondyle, the lowest point of the trochlear crest, and the midpoint of the narrowest part of the distal humeral cortex, wherein the construction of a reference three-dimensional coordinate system based on the preset anatomical feature points in the three-dimensional image data of the elbow joint includes: determining the straight line where the apex of the medial epicondyle and the apex of the lateral epicondyle are located as the X-axis of the reference three-dimensional coordinate system, determining the apex of the lateral epicondyle as the origin of the reference three-dimensional coordinate system, and determining the direction where the apex of the medial epicondyle is located as the positive direction of the X-axis; determining the line perpendicular to the X-axis and passing through the line The plane passing through the lowest point of the trochlear crest is determined as the reference sagittal plane; the straight line parallel to the reference Z axis in the reference sagittal plane and passing through the origin is determined as the Z axis of the reference three-dimensional coordinate system, and the straight line perpendicular to both the X axis and the Z axis is determined as the Y axis of the reference three-dimensional coordinate system, wherein the reference Z axis is a straight line in the reference sagittal plane passing through the midpoint of the narrowest part of the distal humeral cortex and tangent to the innermost side of the cortex of the humeral body; based on the right-hand rule, the positive direction of the Y axis and the positive direction of the Z axis are determined according to the positive direction of the X axis.

[0008] Optionally, the original three-dimensional coordinate system in the three-dimensional image data of the elbow joint includes an original horizontal plane, an original coronal plane and an original sagittal plane, wherein the plane perpendicular to the X-axis and passing through the lowest point of the trochlear crest is determined as the reference sagittal plane, including: translating and rotating the original coronal plane and the original horizontal plane to obtain an adjusted coronal plane, an adjusted horizontal plane and a corresponding adjusted sagittal plane, so that the intersection of the adjusted coronal plane and the adjusted horizontal plane coincides with the X-axis; translating the adjusted sagittal plane within the adjusted coronal plane to pass through the lowest point of the trochlear crest to obtain the reference sagittal plane; wherein the straight line parallel to the reference Z-axis line within the reference sagittal plane and passing through the origin is determined as the reference three-dimensional coordinate system. The Z axis of the reference coordinate system is determined as the Y axis of the reference three-dimensional coordinate system, and a straight line perpendicular to both the X axis and the Z axis is determined as the Y axis of the reference three-dimensional coordinate system, including: translating and rotating the adjusted coronal plane in the reference sagittal plane to obtain a reference coronal plane, so that the reference coronal plane passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost side of the cortex of the humeral body, and rotating the adjusted horizontal plane accordingly to obtain a reference horizontal plane; translating the reference horizontal plane, the reference coronal plane, and the reference sagittal plane until they intersect with each other at the origin, and determining the intersection line obtained by translating the reference coronal plane and the reference sagittal plane as the Z axis, and determining the intersection line obtained by translating the reference horizontal plane and the reference sagittal plane as the Y axis.

[0009] Optionally, constructing multiple elbow joint models with implanted anchors based on the elbow joint three-dimensional image data and the suture anchor data according to the reference three-dimensional coordinates includes: constructing the elbow joint model based on the elbow joint three-dimensional image data; determining the multiple candidate implantation directions in the three-dimensional space described by the reference three-dimensional coordinate system; for each candidate implantation direction, constructing an elbow joint model with the suture anchor implanted into the elbow joint model along the candidate implantation direction based on the suture anchor data, to obtain the multiple elbow joint models with the implanted anchors.

[0010] Optionally, the reference three-dimensional coordinate system includes a horizontal plane, a coronal plane, and a sagittal plane that are mutually perpendicular, the intersection of the horizontal plane and the coronal plane being the X-axis of the reference three-dimensional coordinate system, the intersection of the horizontal plane and the sagittal plane being the Y-axis of the reference three-dimensional coordinate system, and the intersection of the coronal plane and the sagittal plane being the Z-axis of the reference three-dimensional coordinate system. Determining the multiple candidate implantation directions within the three-dimensional space described by the reference three-dimensional coordinate system includes: rotating the horizontal plane by multiple first preset angles around the Y-axis to obtain multiple rotated horizontal planes, and rotating the coronal plane by multiple second preset angles around the Z-axis to obtain multiple rotated coronal planes; determining the direction of the intersection of a rotated horizontal plane and a rotated coronal plane as a candidate implantation direction, and determining the multiple candidate implantation directions based on the multiple rotated horizontal planes and the multiple rotated coronal planes.

[0011] Optionally, the positive direction of the Z-axis is the direction from the distal end of the humerus to the proximal end of the humerus, and the angle of rotation of the horizontal plane around the Y-axis toward the positive direction close to the Z-axis is positive, and the multiple first preset angles are all positive angles; the multiple second preset angles include 0, positive angles and negative angles.

[0012] According to a second aspect of an embodiment of the present disclosure, a device for determining the placement direction of a suture anchor in an elbow joint is provided, the device comprising: an acquisition unit configured to acquire three-dimensional image data and suture anchor data of a target patient's elbow joint; a coordinate construction unit configured to construct a reference three-dimensional coordinate system based on preset anatomical feature points in the three-dimensional image data of the elbow joint; and a model construction unit configured to construct a plurality of elbow joint models with anchors placed therein according to the reference three-dimensional coordinate system based on the three-dimensional image data of the elbow joint and the suture anchor data, wherein the elbow joint of each anchor placed therein is The model is used to represent the placement of a suture anchor into the elbow joint of the target patient along a candidate placement direction, and the multiple elbow joint models with the placed anchors correspond one-to-one to the multiple candidate placement directions; the calculation unit is configured to perform mechanical analysis and calculation on the multiple elbow joint models with the placed anchors, respectively, to obtain mechanical information corresponding to each elbow joint model with the placed anchors; and the determination unit is configured to determine, based on the mechanical information corresponding to each elbow joint model of the multiple elbow joint models with the placed anchors, one of the multiple candidate placement directions corresponding to the multiple elbow joint models with the placed anchors as the preferred placement direction.

[0013] Optionally, the preset anatomical feature points include the apex of the medial epicondyle, the apex of the lateral epicondyle, the lowest point of the trochlear ridge, and the midpoint of the narrowest part of the distal humeral cortex, and the coordinate construction unit is further configured to: determine the straight line connecting the apex of the medial epicondyle and the apex of the lateral epicondyle as the X-axis of the reference three-dimensional coordinate system, determine the apex of the lateral epicondyle as the origin of the reference three-dimensional coordinate system, determine the direction of the apex of the medial epicondyle as the positive direction of the X-axis; determine the plane perpendicular to the X-axis and passing through the lowest point of the trochlear ridge as the origin of the reference three-dimensional coordinate system. The reference sagittal plane is used as the reference plane; a straight line parallel to the reference Z axis in the reference sagittal plane and passing through the origin is determined as the Z axis of the reference three-dimensional coordinate system, and a straight line perpendicular to both the X axis and the Z axis is determined as the Y axis of the reference three-dimensional coordinate system, wherein the reference Z axis is a straight line in the reference sagittal plane that passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost side of the cortex of the humeral body; based on the right-hand rule, the positive directions of the Y axis and the Z axis are determined according to the positive direction of the X axis.

[0014] Optionally, the original three-dimensional coordinate system in the three-dimensional image data of the elbow joint includes an original horizontal plane, an original coronal plane and an original sagittal plane, and the coordinate construction unit is further configured to: translate and rotate the original coronal plane and the original horizontal plane to obtain an adjusted coronal plane, an adjusted horizontal plane and a corresponding adjusted sagittal plane, so that the intersection line of the adjusted coronal plane and the adjusted horizontal plane coincides with the X-axis; in the adjusted coronal plane, translate the adjusted sagittal plane to pass through the lowest point of the trochlear crest to obtain the reference sagittal plane; in the reference sagittal plane, The adjusted coronal plane is translated and rotated to obtain a reference coronal plane, so that the reference coronal plane passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost side of the cortex of the humeral body, and the adjusted horizontal plane is rotated accordingly to obtain a reference horizontal plane; the reference horizontal plane, the reference coronal plane and the reference sagittal plane are translated until they intersect with each other at the origin, and the intersection line obtained by translating the reference coronal plane and the reference sagittal plane is used as the Z axis, and the intersection line obtained by translating the reference horizontal plane and the reference sagittal plane is determined as the Y axis.

[0015] Optionally, the model construction unit is further configured to: construct an elbow joint model based on the three-dimensional image data of the elbow joint; determine the multiple candidate insertion directions in the three-dimensional space described by the reference three-dimensional coordinate system; for each candidate insertion direction, based on the suture anchor data, construct an elbow joint model in which the suture anchor is inserted into the elbow joint model along the candidate insertion direction, thereby obtaining the multiple elbow joint models with the insertion anchors.

[0016] Optionally, the reference three-dimensional coordinate system includes a horizontal plane, a coronal plane, and a sagittal plane that are perpendicular to each other, the intersection of the horizontal plane and the coronal plane being the X-axis of the reference three-dimensional coordinate system, the intersection of the horizontal plane and the sagittal plane being the Y-axis of the reference three-dimensional coordinate system, and the intersection of the coronal plane and the sagittal plane being the Z-axis of the reference three-dimensional coordinate system, and the model construction unit is further configured to: rotate the horizontal plane around the Y-axis by multiple first preset angles to obtain multiple rotated horizontal planes, and rotate the coronal plane around the Z-axis by multiple second preset angles to obtain multiple rotated coronal planes; determine the direction of the intersection of a rotated horizontal plane and a rotated coronal plane as a candidate implantation direction, and determine the multiple candidate implantation directions based on the multiple rotated horizontal planes and the multiple rotated coronal planes.

[0017] Optionally, the positive direction of the Z-axis is the direction from the distal end of the humerus to the proximal end of the humerus, and the angle of rotation of the horizontal plane around the Y-axis toward the positive direction close to the Z-axis is positive, and the multiple first preset angles are all positive angles; the multiple second preset angles include 0, positive angles and negative angles.

[0018] According to a third aspect of an embodiment of the present disclosure, an electronic device is provided, comprising: at least one processor; and at least one memory storing computer-executable instructions, wherein the computer-executable instructions, when executed by the at least one processor, prompt the at least one processor to execute a method for determining an elbow joint suture anchor placement direction according to an exemplary embodiment of the present disclosure.

[0019] According to a fourth aspect of an embodiment of the present disclosure, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by at least one processor, the at least one processor is prompted to execute a method for determining an elbow joint suture anchor placement direction according to an exemplary embodiment of the present disclosure.

[0020] According to a fifth aspect of an embodiment of the present disclosure, a computer program product is provided, comprising computer instructions, which, when executed by at least one processor, prompt the at least one processor to execute a method for determining an elbow joint suture anchor placement direction according to an exemplary embodiment of the present disclosure.

[0021] The technical solution provided by the embodiments of the present disclosure brings at least the following beneficial effects: According to the method and device for determining the insertion direction of the elbow joint suture anchor disclosed in the present disclosure, the reference three-dimensional coordinate system is constructed by taking the preset anatomical feature points inherent in the human body as a reference, and a unified three-dimensional coordinate system can be reliably constructed, thereby accurately quantitatively describing the insertion point and insertion direction of the suture anchor, and establishing a model of the suture anchor being inserted into the elbow joint along different insertion directions. On this basis, by analyzing the mechanical strength of the suture anchor at different insertion angles, the preferred insertion direction of the suture anchor is determined, which helps to reduce the occurrence of suture anchors penetrating the cortical bone, falling or entering the joint during surgery, and reduces the occurrence of surgical failures due to loosening, displacement, and extraction of the suture anchor after surgery. The method disclosed in the present disclosure helps to achieve accurate preoperative planning, thereby improving the safety of elbow arthroscopic surgery, reducing the surgeon's dependence on arthroscopic surgery experience, and reducing medical costs.

[0022] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the description are used to explain the principles of the present disclosure, and do not constitute an improper limitation of the present disclosure.

[0024] Figure 1 is a flow chart of a method for determining an implantation direction of an elbow joint suture anchor according to an exemplary embodiment of the present disclosure.

[0025] Figure 2is a schematic diagram of the bones of an elbow joint according to an exemplary embodiment of the present disclosure.

[0026] Figure 3 is a schematic diagram of a reference three-dimensional coordinate system according to an exemplary embodiment of the present disclosure.

[0027] Figure 4 1 is a schematic diagram of a two-dimensional image of a reconstructed image on three original planes according to a specific embodiment of the present disclosure.

[0028] Figure 5 3 is a schematic diagram of a two-dimensional image of a reconstructed image on three adjustment planes according to a specific embodiment of the present disclosure.

[0029] Figure 6 It is a schematic diagram of a two-dimensional image of a reconstructed image in an adjusted coronal plane, an adjusted horizontal plane after translation, and a reference sagittal plane according to a specific embodiment of the present disclosure.

[0030] Figure 7 It is a schematic diagram of a two-dimensional image of a reconstructed image according to a specific embodiment of the present disclosure, including an adjusted coronal plane after translation, an adjusted horizontal plane after further translation, and a reference sagittal plane.

[0031] Figure 8 3 is a schematic diagram of a two-dimensional image of a reconstructed image on three reference planes according to a specific embodiment of the present disclosure.

[0032] Figure 9 1 is a schematic diagram of two-dimensional images of three planes of a reference three-dimensional coordinate system of a reconstructed image according to a specific embodiment of the present disclosure.

[0033] Figure 10 FIG. 4 is a schematic diagram of an elbow joint model with an anchor placed according to an exemplary embodiment of the present disclosure.

[0034] Figure 11 is a schematic diagram of multiple rotating horizontal planes according to an exemplary embodiment of the present disclosure.

[0035] Figure 12 1 is a schematic diagram of multiple rotated coronal planes according to an exemplary embodiment of the present disclosure.

[0036] Figure 13 is a schematic diagram of a finite element mesh according to a specific embodiment of the present disclosure.

[0037] Figure 14 is a block diagram of an apparatus for determining an implantation direction of a suture anchor in an elbow joint according to an exemplary embodiment of the present disclosure.

[0038] Figure 15 is a block diagram of an electronic device according to an exemplary embodiment of the present disclosure.

[0039] Figure 2Description of Figure Numbers:

[0040] 10: Humerus; 11: Medial epicondyle; 12: Lateral epicondyle; 13: Capitellum; 14: Humeral trochlea;

[0041] 20: radius; 21: radial head; 22: radial tuberosity;

[0042] 30: ulna; 31: olecranon; 32: trochlear notch; 33: coronoid process. DETAILED DESCRIPTION

[0043] In order to enable ordinary persons in the art to better understand the technical solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0044] It should be noted that the terms "first," "second," and the like in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the numbers used in this manner are interchangeable where appropriate so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The implementation methods described in the following examples do not represent all implementation methods consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with certain aspects of the present disclosure as detailed in the appended claims.

[0045] It should be noted that the phrase "at least one of the items" in this disclosure includes three types of parallel situations: "any one of the items", "a combination of any multiple items of the items", and "all of the items". For example, "including at least one of A and B" includes the following three parallel situations: (1) including A; (2) including B; (3) including A and B. For another example, "performing at least one of step 1 and step 2" includes the following three parallel situations: (1) performing step 1; (2) performing step 2; and (3) performing steps 1 and 2.

[0046] Hereinafter, a method and apparatus for determining the placement direction of an elbow joint suture anchor, an electronic device, and a storage medium according to exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0047] Figure 1 The present invention is a flowchart of a method for determining the placement direction of an elbow joint suture anchor according to an exemplary embodiment of the present invention. The method can be executed on an electronic device with sufficient computing power.

[0048] Reference Figure 1 In step S101, three-dimensional image data and suture anchor data of the target patient's elbow joint are obtained.

[0049] The three-dimensional image data of the elbow joint is obtained by photographing the elbow joint of the target patient using medical equipment, and includes, for example but not limited to, CT data and MRI data.

[0050] Suture anchor data is data used to describe the suture anchor, for example, including but not limited to the structural dimension data, material property data, and insertion point data of the suture anchor. Among them, the structural dimension data and material property data are data used to describe the suture anchor itself, and the insertion point data is data used to describe the insertion point when the suture anchor is inserted into the elbow joint, specifically located near the apex of the lateral epicondyle of the humerus. For example, it can be determined by combining existing surgical experience, or by other theoretical analysis methods. The present disclosure does not limit this, and it can be fine-tuned during the subsequent modeling and analysis process.

[0051] In step S102, a reference three-dimensional coordinate system is constructed based on preset anatomical feature points in the three-dimensional image data of the elbow joint.

[0052] Anatomical feature points are inherent feature points of the human skeleton, while preset anatomical feature points are pre-selected anatomical feature points, including but not limited to the vertices of the medial and lateral epicondyles of the humerus. By using the inherent preset anatomical feature points of the human body as a benchmark to construct a reference three-dimensional coordinate system, a unified three-dimensional coordinate system can be reliably constructed, thereby accurately quantitatively describing the insertion point and insertion direction of the suture anchor. In subsequent steps, a model of suture anchors inserted into the elbow joint along different insertion directions can be established. In addition, constructing a unified three-dimensional coordinate system between different individual samples is also conducive to studying more general biological laws.

[0053] In step S103, based on the elbow joint three-dimensional image data and the suture anchor data, a plurality of elbow joint models with anchors inserted are constructed according to a reference three-dimensional coordinate system.

[0054] As the name suggests, the elbow joint model with suture anchors inserted is a model of the elbow joint with suture anchors inserted. Therefore, constructing a model requires not only the three-dimensional elbow joint image data and suture anchor data acquired in step S101, but also a specific insertion direction. Each elbow joint model with suture anchors inserted represents the insertion of a suture anchor into the target patient's elbow joint along a candidate insertion direction. Multiple elbow joint models with suture anchors correspond one-to-one to multiple candidate insertion directions, thereby enabling modeling for different candidate insertion directions.

[0055] In step S104, mechanical analysis and calculation are performed on the multiple elbow joint models with anchor pins inserted, and mechanical information corresponding to each elbow joint model with anchor pins inserted is obtained.

[0056] This step can be implemented with reference to existing mechanical analysis and calculation methods, such as, but not limited to, the finite element method. Specifically, in general, the research methods for bone tissue mainly include physical experimental methods and mathematical calculation methods. The physical experimental method has poor repeatability, high cost, and low research efficiency. For the mathematical calculation method, human bone tissue has complex geometric shapes and mechanical properties. Using traditional mathematical methods to calculate the mechanical properties of bone tissue not only makes the calculation process complicated, but also has large errors in the calculation results. As a numerical analysis method with a theoretical basis and wide application effectiveness, the finite element method can solve complex problems with irregular boundary conditions and structural shapes. The finite element method can well simulate the complex shape of bone tissue, give bone tissue different material properties, and impose various load conditions on bone tissue, so as to obtain more realistic calculation results. Before performing finite element calculations, the finite element model needs to be processed, which is the process of modeling. How to establish a finite element model that is as realistic as possible is the key to the finite element method.

[0057] Existing finite element model building techniques usually include the following steps:

[0058] 1. First, 3D reconstruction is performed using medical imaging data such as CT and MRI, mainly including grayscale threshold segmentation and deep learning segmentation methods. Then, the 3D model is optimized, such as smoothing, filling, cleaning, etc., to obtain a 3D bone tissue model that is more consistent with the physiological morphology.

[0059] 2. Use 3D editing software such as Solidworks and UG (Unigraphics) to assemble bone tissue or simulate surgical operations, such as partial resection and assembly of medical devices.

[0060] 3. Divide the 3D model processed in step 2 into a grid using pre-processing software such as Hypermesh.

[0061] 4. Import the mesh data into finite element simulation software such as Ansys, Abaqus, etc., assign material properties to the finite element model, add loads and boundary conditions, and finally perform finite element analysis.

[0062] It should be understood that existing finite element modeling methods, due to their lack of a unified three-dimensional coordinate system, cannot create a bone-anchor finite element model as accurate as the anchor-placed elbow joint model of the exemplary embodiment of the present disclosure. However, the exemplary embodiment of the present disclosure, based on the construction and use of a unified reference three-dimensional coordinate system, can still refer to existing finite element modeling techniques to perform model assembly operations, meshing processing, and mechanical analysis calculations.

[0063] In step S105 , based on the mechanical information corresponding to each of the multiple elbow joint models with the anchors placed, one of the multiple candidate placement directions corresponding to the multiple elbow joint models with the anchors placed is determined as a preferred placement direction.

[0064] Based on the construction of an elbow joint model with multiple anchors corresponding to multiple candidate insertion directions, the optimal insertion direction of the suture anchor is determined by analyzing the mechanical strength of the suture anchor at different insertion angles. This helps to reduce the risk of the suture anchor penetrating the cortical bone (the bone includes the cancellous bone located inside and the cortical bone covering the cancellous bone), falling or entering the joint during surgery, and reduces the risk of surgical failure due to loosening, displacement or extraction of the suture anchor after surgery. The disclosed method helps achieve accurate preoperative planning, thereby improving the safety of elbow arthroscopic surgery, reducing the surgeon's reliance on arthroscopic surgical experience, and lowering medical costs.

[0065] It should be noted that the various steps in the exemplary embodiments of the present disclosure can be executed by manually operating software or by a computer calling software through an algorithm. These are all implementation methods of the present disclosure and fall within the scope of protection of the present disclosure.

[0066] Next, the above step S102 is further introduced.

[0067] like Figure 2 As shown, the bones associated with the elbow joint include the humerus 10, the radius 20, and the ulna 30. The structures on the humerus 10 mainly include the medial epicondyle 11, the lateral epicondyle 12, the capitellum 13, and the trochlea 14. The structures on the radius 20 mainly include the radial head 21 and the radial tuberosity 22. The structures on the ulna 30 mainly include the olecranon 31, the trochlear notch 32, and the coronoid process 33. Preset anatomical feature points can be selected from the anatomical feature points of these bone structures, such as the lowest point P of the trochlea ridge on the trochlea 14. Since the above structures are mainly used in the following text, and the focus of this disclosure is on the method flow, the above structures are no longer numbered.

[0068] Regarding the construction of the reference three-dimensional coordinate system, in principle, optionally, the preset anatomical feature points include the apex of the medial epicondyle, the apex of the lateral epicondyle, the lowest point of the trochlear crest, and the midpoint of the narrowest part of the distal humeral cortex. The execution principle of step S102 is to first determine the X-axis and then determine the Z-axis, specifically including: determining the straight line connecting the apex of the medial epicondyle and the apex of the lateral epicondyle as the X-axis of the reference three-dimensional coordinate system, determining the apex of the lateral epicondyle as the origin of the reference three-dimensional coordinate system, and determining the direction where the apex of the medial epicondyle is located as the positive direction of the X-axis; The plane perpendicular to the X-axis and passing through the lowest point of the trochlear crest is defined as the reference sagittal plane. A line parallel to the reference Z-axis within the reference sagittal plane and passing through the origin is defined as the Z-axis of the reference three-dimensional coordinate system. A line perpendicular to both the X-axis and the Z-axis is defined as the Y-axis of the reference three-dimensional coordinate system. The reference Z-axis is the line that passes through the midpoint of the narrowest part of the distal humeral cortex within the reference sagittal plane and is tangent to the medialmost cortical aspect of the humeral body. Based on the right-hand rule, the positive directions of the Y and Z axes are determined based on the positive direction of the X-axis. By first determining the X-axis and its positive direction based on the apex of the medial and lateral epicondyles, the direction of extension of the sagittal plane perpendicular to the X-axis can be determined accordingly. On this basis, one of the countless sagittal planes perpendicular to the X-axis that passes through the lowest point of the trochlear crest is determined as the reference sagittal plane. This reference sagittal plane can pass through the humerus to form a clear section, and within this section, the cortical thickness of the distal humerus varies significantly. By taking the midpoint of the narrowest part of the cortex of the distal humerus in the reference sagittal plane as a reference and referring to the cortex of the humeral body, a straight line passing through the midpoint of the narrowest part of the cortex of the distal humerus and tangent to the innermost cortex of the humeral body can be determined. The direction of this straight line is determined as the reference Z-axis line, and the direction parallel to the extension direction of the Z-axis can be determined, thereby determining the Z-axis based on the position of the coordinate origin, and then determining the direction of the Y-axis and each axis, so that the reference three-dimensional coordinate system can be reliably constructed. The reference three-dimensional coordinate system finally determined using this principle is as follows: Figure 3 It should be noted that for the convenience of intuitive viewing, Figure 3 Only the positive half of the X, Y, and Z axes are drawn.

[0069] It should be understood that the core of the present disclosure is to use anatomical feature points as a benchmark to construct a reference three-dimensional coordinate system. In addition to the exemplified points of the medial epicondyle apex, the lateral epicondyle apex, the lowest point of the trochlear crest, and the midpoint of the narrowest part of the distal humeral cortex, other anatomical feature points can also be used as preset anatomical feature points, and a reliable reference three-dimensional coordinate system can be constructed accordingly. The present disclosure does not limit this. In addition, these preset anatomical feature points can be marked manually or automatically by a computer using a reasonable algorithm, such as but not limited to the PCA (Principal Component Analysis) method based on point cloud and the deep learning method based on the UNet network. The present disclosure does not limit this.

[0070] The steps for marking the vertices of the medial and lateral epicondyles using the point cloud-based PCA method include:

[0071] 1. Obtain point cloud data. This step uses the point cloud data of the distal humerus to represent its surface shape.

[0072] 2. Perform PCA analysis. This step uses PCA to extract the principal axis direction of the point cloud data, resulting in the following three mutually perpendicular principal component vectors: the first principal component vector (denoted as PC1) is along the direction of maximum variance in the data, i.e., the direction of the humeral shaft (parallel to the Z axis); the second principal component vector (denoted as PC2) is perpendicular to PC1 and along the direction of the second largest variance, i.e., the line connecting the vertices of the medial and lateral epicondyles (in the X axis direction); the third principal component vector (denoted as PC3) is perpendicular to the first two principal component vectors.

[0073] 3. Determine the feature points. This step projects all point clouds onto the plane formed by PC1 and PC2 (coronal plane). The two outermost points are the vertices of the medial and lateral epicondyles.

[0074] The steps for marking the vertices of the medial and lateral epicondyles using a deep learning method based on a UNet network include:

[0075] 1. Sample labeling: In this step, for each elbow joint 3D image data sample, the 3D coordinates of the vertices of the medial epicondyle and the lateral epicondyle are manually labeled.

[0076] 2. Network Design. This step uses a standard UNet network to extract features through downsampling (Encoder) and reconstruct spatial information through upsampling (Decoder). The network input is 3D voxels, and the output is the position coordinates of the vertices of the medial and lateral epicondyles.

[0077] 3. Model training: This step trains the UNet network using a supervised training method, and the loss function uses MSE (Mean Squared Error).

[0078] 4. Use the trained model to predict the coordinates of the medial and lateral epicondyle vertices.

[0079] For the several preset anatomical feature points and the corresponding coordinate construction principles shown above, appropriate operation steps can be flexibly selected when performing specific operations.

[0080] As an example, since the three-dimensional image data of the elbow joint can usually be viewed and processed in medical image processing software, such as but not limited to using MPR (MultiPlanar Reconstruction) technology to reconstruct the three-dimensional image data of the elbow joint, the three-dimensional image data of the elbow joint can be converted into a two-dimensional image displayed on three different planes: the horizontal plane (a plane that divides the human body into upper and lower parts), the coronal plane (a plane that divides the human body into front and back parts), and the sagittal plane (a plane that divides the human body into left and right parts). Based on this, these three types of planes can be translated and rotated in the medical image processing software to finally obtain the corresponding three planes that conform to the reference three-dimensional coordinate system, and then the reference three-dimensional coordinate system is determined by combining the origin, the X-axis, and the direction of the X-axis. Specifically, when reconstructing the three-dimensional image data of the elbow joint, the medical image processing software will provide an original three-dimensional coordinate system, and the horizontal plane, the coronal plane, and the sagittal plane in the original three-dimensional coordinate system will be recorded as the original horizontal plane, the original coronal plane, and the original sagittal plane, respectively. When executing step S102, these three original planes can be translated and rotated.

[0081] Optionally, the operation of determining the plane perpendicular to the X-axis and passing through the lowest point of the trochlear crest as the reference sagittal plane in step S102 includes: translating and rotating the original coronal plane and the original horizontal plane to obtain an adjusted coronal plane, an adjusted horizontal plane, and a corresponding adjusted sagittal plane, so that the intersection of the adjusted coronal plane and the adjusted horizontal plane coincides with the X-axis; within the adjusted coronal plane, translating the adjusted sagittal plane to pass through the lowest point of the trochlear crest to obtain a reference sagittal plane. This operation method can quickly determine the reference sagittal plane by first adjusting the original three planes based on the X-axis, and then translating the adjusted sagittal plane based on the three adjusted planes and the plane passing through the lowest point of the trochlear crest as a reference. It should be understood that the "corresponding adjusted sagittal plane" refers to a plane that is perpendicular to both the adjusted coronal plane and the adjusted horizontal plane. It should also be understood that when adjusting the sagittal plane by translation, the coronal plane may be adjusted by translation synchronously or not, which does not affect the extension direction of the sagittal plane. The present disclosure does not impose any restrictions on this. Similar translation operations on one of the planes below are the same and will not be explained one by one.

[0082] Optionally, in step S102, determining a line parallel to the reference Z axis in the reference sagittal plane and passing through the origin as the Z axis of the reference three-dimensional coordinate system, and determining a line perpendicular to both the X axis and the Z axis as the Y axis of the reference three-dimensional coordinate system includes: translating and rotating the adjusted coronal plane in the reference sagittal plane to obtain a reference coronal plane, such that the reference coronal plane passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost cortex of the humeral body, and rotating the adjusted horizontal plane accordingly to obtain a reference horizontal plane; translating the reference horizontal plane, the reference coronal plane, and the reference sagittal plane until they intersect at the origin, determining the intersection of the translated reference coronal plane and the reference sagittal plane as the Z axis, and determining the intersection of the translated reference horizontal plane and the reference sagittal plane as the Y axis. Since, in the three-dimensional coordinate system, the line on which the Z axis lies is the intersection of the coronal and sagittal planes, the projection line of the coronal plane in the sagittal plane can be used to represent the Z axis. Based on this, by implementing the determination operation of the reference Z axis as a translation and rotation operation of the adjustment coronal plane in the reference sagittal plane, the axis determination can be conveniently achieved through surface operation. Specifically, the adjustment coronal plane can be first translated to the midpoint passing through the narrowest part of the distal humeral cortex, and then the translated adjustment coronal plane can be rotated with this point as the center to be tangent to the innermost cortex of the humeral body. Similarly, the straight line where the Y axis is located is the intersection of the horizontal plane and the sagittal plane, and the horizontal plane needs to remain perpendicular to the coronal plane. Therefore, by making the adjustment horizontal plane rotate synchronously with the adjustment coronal plane and determining the Y axis accordingly, the axis determination can also be conveniently achieved through surface operation.

[0083] Next, combine Figures 4 to 9 A method for constructing a reference three-dimensional coordinate system according to a specific embodiment of the present disclosure is introduced.

[0084] The three-dimensional image data of the elbow joint in this embodiment is CT data. The image reconstruction is realized by using MPR technology, and the construction of the reference three-dimensional coordinate system is realized by translating and rotating the original three planes. Figure 4 As shown, it is determined by the CT shooting angle. Figure 4 In the figure, the image in the upper left corner is the two-dimensional image of the reconstructed image in the original horizontal plane, and the image in the lower left corner is the two-dimensional image of the reconstructed image in the original coronal plane. Among these two-dimensional images, the image in the upper right corner is the two-dimensional image of the reconstructed image in the original sagittal plane. The red straight line, green straight line, and orange straight line represent the horizontal plane projection, coronal plane projection, and sagittal plane projection, respectively. By translating and rotating the two straight lines in the figure in the two-dimensional image of any plane, operations on the two planes corresponding to the two straight lines can be achieved, and the two-dimensional image of the operated plane will change accordingly. Figures 5 to 9 Similarly, I will not explain them one by one.

[0085] First, through Figure 4The original horizontal plane (red straight line) and the original coronal plane (green straight line) in the image are translated and rotated so that the line connecting the vertices of the medial epicondyle and the lateral epicondyle is located on the intersection of the coronal plane and the horizontal plane, and the following is obtained: Figure 5 The adjusted horizontal plane (upper left corner), adjusted coronal plane (lower left corner), and adjusted sagittal plane (upper right corner) are shown, where the red marked points at the upper and lower parts of the adjusted horizontal plane are the vertices of the lateral epicondyle and the vertices of the medial epicondyle, respectively; the red marked points at the lower right and upper left parts of the adjusted coronal plane are the vertices of the lateral epicondyle and the vertices of the medial epicondyle, respectively; the line connecting the vertices of the medial and lateral epicondyles is the X-axis, and the vertices of the lateral epicondyle are the origin, and the vertices of the medial epicondyle are located on the positive side of the X-axis.

[0086] Second, in Figure 5 In the adjusted coronal plane (lower left corner) shown, the adjusted horizontal plane (red straight line) and the adjusted sagittal plane (orange straight line) are translated so that the intersection line of the horizontal plane and the sagittal plane (the intersection of the red and orange straight lines) passes through the lowest point of the trochlear crest, as shown in FIG. Figure 6 As shown in the adjusted coronal plane in the lower left corner, the sagittal plane obtained at this time is the reference sagittal plane.

[0087] Third, in Figure 6 In the reference sagittal plane (upper right corner) shown in the figure, the adjusted horizontal plane (red straight line) and the adjusted coronal plane (green straight line) are translated so that the intersection of the horizontal plane and the coronal plane (the intersection of the red and green straight lines) passes through the midpoint of the narrowest part of the distal humeral cortex, as shown in the figure. Figure 7 The reference sagittal plane is shown in the upper right corner.

[0088] Fourth, in Figure 7 In the reference sagittal plane (upper right corner), the translated coronal plane (green line) is rotated around the midpoint of the narrowest part of the distal humeral cortex so that it is tangent to the innermost cortex of the humeral body, as shown in Figure 2. Figure 8 As shown in the reference sagittal plane in the upper right corner, the horizontal plane and coronal plane obtained at this time are the reference horizontal plane and reference coronal plane, respectively.

[0089] Fifth, after determining the reference horizontal plane, reference coronal plane, and reference sagittal plane, the extension directions of the coronal plane, sagittal plane, and horizontal plane have been determined, and the intersection of the three planes will be used as the origin of the coordinate system. Therefore, it is only necessary to translate the three reference planes to modify the origin to the apex of the lateral epicondyle. The three planes of the reference three-dimensional coordinate system finally constructed are as follows: Figure 9 shown.

[0090] Next, the above step S103 is further introduced.

[0091] Optionally, step S103 includes: constructing an elbow joint model based on the three-dimensional image data of the elbow joint; determining multiple candidate insertion directions based on the reference three-dimensional coordinate system; for each candidate insertion direction, constructing an elbow joint model with the suture anchor inserted into the elbow joint model along the candidate insertion direction based on the suture anchor data, and obtaining multiple elbow joint models with the suture anchor inserted. The operations of constructing the elbow joint model and constructing the elbow joint model with the anchor inserted for a specific candidate insertion direction can refer to the existing finite element modeling technology to perform assembly operations on the model (for example, including but not limited to removing part of the bone tissue and inserting the suture anchor), meshing processing and mechanical analysis calculations. The elbow joint model with the anchor inserted that is finally constructed is, for example Figure 10 shown.

[0092] It should be noted that, as mentioned above, the three-dimensional image data of the elbow joint can be viewed and processed in the medical image processing software to realize the construction of the reference three-dimensional coordinate system, but the constructed coordinate system can usually only be viewed in the medical image processing software. In other words, the elbow joint model constructed based on the three-dimensional image data of the elbow joint may not have a coordinate system mark. Based on this, the coordinates of the key points of the reference three-dimensional coordinate system can be marked in the medical image processing software. The key points include, for example, but are not limited to the vertex of the medial epicondyle and the vertex of the lateral epicondyle (used to determine the origin, the X-axis, the positive direction of the X-axis), and any two points on the Z-axis or the Y-axis (used to determine the Z-axis or the Y-axis). As long as they can be used to determine the reference three-dimensional coordinate system, when constructing the elbow joint model, these key points can be used to re-determine the reference three-dimensional coordinate system in the model.

[0093] It should be understood that since different elbow joint models for anchor placement differ primarily in the use of different candidate placement directions, step S103 focuses on how to determine multiple candidate placement directions. Specifically, the reference three-dimensional coordinate system includes mutually perpendicular horizontal, coronal, and sagittal planes. The intersection of the horizontal and coronal planes is the X-axis of the reference three-dimensional coordinate system, the intersection of the horizontal and sagittal planes is the Y-axis of the reference three-dimensional coordinate system, and the intersection of the coronal and sagittal planes is the Z-axis of the reference three-dimensional coordinate system.

[0094] In some embodiments, optionally, the operation of determining multiple candidate implantation directions based on the reference three-dimensional coordinate system includes: determining multiple candidate implantation directions in the horizontal plane of the reference three-dimensional coordinate system, and / or determining multiple candidate implantation directions in the coronal plane of the reference three-dimensional coordinate system, to obtain multiple candidate implantation directions. Figure 3 In the embodiment of the reference three-dimensional coordinate system shown, since the suture anchor needs to be placed in the humerus, and the sagittal plane perpendicular to the X-axis has only one intersection with the humerus, namely the vertex of the medial epicondyle, there is no need to determine the candidate placement direction in the sagittal plane.

[0095] In other embodiments, optionally, determining multiple candidate insertion directions based on a reference three-dimensional coordinate system includes determining the multiple candidate insertion directions within a three-dimensional space described by the reference three-dimensional coordinate system. By determining the candidate insertion directions within three-dimensional space, rather than solely within a two-dimensional plane, a richer and more accurate description of the insertion directions can be achieved, facilitating accurate preoperative planning and thereby improving the safety of elbow arthroscopic surgery.

[0096] In some other embodiments described above, optionally, the operation of determining multiple candidate placement directions in the three-dimensional space described by the reference three-dimensional coordinate system includes: referring to Figure 3 The horizontal plane (i.e., the XOY plane) is rotated about the Y axis by multiple first preset angles to obtain multiple rotated horizontal planes, and the coronal plane (i.e., the XOZ plane) is rotated about the Z axis by multiple second preset angles to obtain multiple rotated coronal planes. The direction of the intersection of a rotated horizontal plane and a rotated coronal plane is determined as a candidate implantation direction. Based on the multiple rotated horizontal planes and the multiple rotated coronal planes, multiple candidate implantation directions are determined. By first determining multiple rotated horizontal planes (equivalent to determining multiple implantation directions within the coronal plane) and multiple rotated coronal planes (equivalent to determining multiple implantation directions within the horizontal plane), and then pairing these multiple rotated horizontal planes with the multiple rotated coronal planes, the direction represented by the vector sum of the unit vector of an implantation direction within the coronal plane and the unit vector of an implantation direction within the horizontal plane is determined as a candidate implantation direction. This method can clearly and logically obtain multiple candidate implantation directions in three-dimensional space (the number of which is the product of the number of rotated horizontal planes and the number of rotated coronal planes).

[0097] Alternatively, refer to Figure 3 The reference three-dimensional coordinate system shown in FIG. 1 is a reference three-dimensional coordinate system. The origin of the reference three-dimensional coordinate system is located on one side of the distal end of the humerus (e.g., the vertex of the lateral epicondyle described above). The positive direction of the Z axis is from the distal end of the humerus to the proximal end of the humerus. The X axis runs transversely through the humerus. The positive direction of the X axis is from one side of the humerus to the other side of the humerus. For the first preset angle, as shown in FIG. Figure 11 As shown, the angle of rotation of the horizontal plane around the Y-axis toward the positive direction close to the Z-axis is positive, and multiple first preset angles are all positive angles, so that the insertion direction pointing to the inside of the humerus can be determined in the coronal plane. For the second preset angle, the multiple second preset angles include 0, positive angles and negative angles. Since the coronal plane passes through the humerus, no matter which direction it deflects in the horizontal plane, it can point to the inside of the humerus, so that the insertion direction pointing to the inside of the humerus can be determined in the horizontal plane. Of course, the specific absolute value of the angle needs to be reasonably determined to ensure that the insertion direction points to the inside of the humerus. As an example, Figure 11 As shown, the first preset angles include 15°, 30°, and 45°. Figure 12As shown, the multiple second preset angles include -10°, 0°, and 10°, that is, the initial coronal plane before rotation of the reference three-dimensional coordinate system is also used as a rotated coronal plane, while the initial horizontal plane before rotation is not used as a rotated horizontal plane.

[0098] Next, a method for determining the placement direction of an elbow joint suture anchor according to a specific embodiment of the present disclosure is introduced. This specific embodiment does not separately describe the step of initially acquiring data (ie, step S101).

[0099] Step 1: Construct a unified reference three-dimensional coordinate system of the distal humerus based on the medical imaging data (corresponding to the operation of obtaining the three-dimensional imaging data of the elbow joint in S101 and step S102).

[0100] The target patient's elbow joint CT image data was obtained as 3D elbow joint image data based on computed tomography (DICOM) images. The DICOM-formatted 3D elbow joint image data was then imported into the medical image processing software MIMICS 21.0 for processing.

[0101] During the processing, the three-dimensional image of the elbow joint was first reconstructed by MPR, and the line connecting the vertices of the medial and lateral epicondyles was selected as the X-axis (the vertices of the lateral epicondyle were the origin, and the vertices of the medial epicondyle were located on the positive side of the X-axis); the original coronal plane, the original horizontal plane, and the original sagittal plane were translated and rotated to obtain the adjusted coronal plane, the adjusted horizontal plane, and the adjusted sagittal plane, so that the line connecting the vertices of the medial and lateral epicondyles was located on the intersection of the adjusted coronal plane and the adjusted horizontal plane; the adjusted sagittal plane was moved to pass through the lowest point of the trochlear crest in the adjusted coronal plane to obtain the reference sagittal plane; the adjusted coronal plane was first moved to pass through the humeral ridge in the reference sagittal plane. The midpoint of the narrowest part of the distal cortex of the bone is then rotated around the midpoint of the narrowest part of the distal cortex of the humerus to be tangent to the innermost cortex of the humeral body to obtain the reference coronal plane and the corresponding reference horizontal plane; the three reference planes are moved to intersect at the apex of the lateral epicondyle (i.e., the origin) to obtain the three planes of the reference three-dimensional coordinate system; the intersection of the horizontal plane and the sagittal plane is determined as the Y axis of the reference three-dimensional coordinate system, and the intersection of the coronal plane and the sagittal plane is determined as the Z axis of the reference three-dimensional coordinate system; based on the right-hand rule, the positive direction of the Y axis and the positive direction of the Z axis are determined according to the positive direction of the X axis to establish a reference three-dimensional coordinate system. For detailed process, please refer to the above and Figures 3 to 9 .

[0102] After the establishment is completed, the coordinates of the medial epicondyle vertex, the lateral epicondyle vertex and two arbitrary points on the Z axis (as key points) in the reference three-dimensional coordinate system are recorded.

[0103] Step 2: Construct a three-dimensional model of the distal humerus based on the medical imaging data as an elbow joint model for inserting multiple anchors (corresponding to the operation of obtaining suture anchor data in step S101 and step S103).

[0104] First, the bones are segmented according to the CT grayscale and a mask is generated. Then, the edge contours of the bones are filled and cleaned to obtain a bone mask with a clear contour boundary. Finally, the bone mask is smoothed and the processed mask is used to output a triangular mesh file in STL (Stereolithography) format.

[0105] Because the triangular mesh was too fine to mesh the bone surface, the STL file was re-meshed using the reverse modeling software Geomagic. The smoothing function in the software was used to further smooth the bone surface. The offset function was then used to offset the surface inward to form the cancellous bone surface. The unoffset bone served as the cortical bone model. Finally, the offset and unoffset files were exported to STP format. The specific offset amount was the thickness of the cortical bone near the lateral epicondyle of the target patient's humerus, as measured using CT images.

[0106] Then import the cortical bone model into SolidWorks, create a reference 3D coordinate system based on the key coordinate points in step 1, and use the newly created reference 3D coordinate system as the global coordinate system. Based on the surgical experience of elbow arthroscopy, preliminarily determine the insertion point of the suture anchor, and use the 3D sketch function to mark the anchor insertion point. Figure 3 It is a three-dimensional model of cortical bone. The three straight lines represent the three coordinate axes after reconstruction. The point above the coordinate origin is the insertion point of the suture anchor. Then, a series of rotated horizontal planes and rotated coronal planes are generated based on the horizontal plane and the coronal plane to facilitate the simulation of candidate insertion directions of the suture anchor. This specific embodiment uses 9 directions as candidate insertion directions based on surgical experience. Figure 3 , the positive and negative directions of the Y axis are called the front side and the back side respectively, and the positive and negative directions of the Z axis are called the bottom side and the top side respectively. Figure 11 As shown in the figure, the projection of the horizontal plane on the coronal plane is observed from the front, and the horizontal plane is rotated clockwise by 15°, 30°, and 45°, that is, the horizontal plane is rotated 15°, 30°, and 45° around the Y axis toward the direction close to the positive direction of the Z axis to obtain three rotated horizontal planes. Figure 12 As shown in the figure, the projection of the coronal plane onto the horizontal plane is viewed from the upper side. With clockwise rotation as positive, the coronal plane is rotated by -10°, 0°, and 10°. That is, the coronal plane is rotated 10° in opposite directions around the Z axis. Adding the coronal plane itself, three rotated coronal planes are obtained. Combining the three rotated horizontal and three rotated coronal planes in pairs, the angle between a rotated horizontal and a rotated coronal plane is used as a candidate implantation direction, resulting in nine candidate implantation directions.

[0107] Finally, import the cortical bone, cancellous bone, and anchor models (constructed from the suture anchor data) into a SolidWorks assembly drawing. Assemble the cortical and cancellous bones, then configure the suture anchor to humerus fit. The suture anchor insertion point must be collinear with the anchor axis, and the anchor axis must be aligned with the candidate insertion direction. After the fit is complete, inspect the 3D model. If the suture anchor penetrates the cortex in a model with a candidate insertion direction, correct the suture anchor insertion point in that model by shifting it 2 mm in the negative Y-axis direction. If the suture anchor still penetrates the cortex after this shift, continue shifting until the suture anchor is properly inserted into the cancellous bone. After the assembly is complete, save it as an SLDASM (SolidWorks software file extension, representing SolidWorks Assembly) file. Figure 10 This is the assembled model, which includes cortical bone, cancellous bone, and suture anchors.

[0108] Step 3: Perform finite element analysis calculation on the constructed model (corresponding to step S104).

[0109] 1) Divide the finite element mesh based on the 3D model of the distal humerus.

[0110] Use the finite element pre-processing software Hypermesh to divide the mesh and import the assembly file in step 2. First, perform geometric cleaning, remove small features, and repair missing geometric lines. Then perform Boolean operations on the bones and suture anchors to prevent interference. Then use tetrahedral mesh to divide the model into finite element meshes, using 0.1mm mesh for the suture anchor part and 0.1-10mm mesh for the humerus part. After meshing, output the INP (Input) format files of cortical bone, cancellous bone and suture anchor respectively, and then use Abaqus for finite element analysis. Figure 13 It is the finite element mesh after dividing the tetrahedral elements, which includes three parts: cortical bone, cancellous bone and suture anchor.

[0111] 2) Establish a finite element model based on the anchor-humerus connection relationship.

[0112] A finite element model was created using the finite element analysis software Abaqus, importing the INP file generated in the previous step. Different material properties were assigned to the cortical bone, cancellous bone, and suture anchor. Based on the suture anchor data, the elastic modulus of the suture anchor was set to 200 MPa and the Poisson's ratio to 0.35. The elastic modulus of the cortical bone was set to 80 MPa and the Poisson's ratio to 0.3, and the elastic modulus of the cancellous bone was set to 2 MPa and the Poisson's ratio to 0.26. A tensile force of 100 N was applied along the axis of the suture anchor to simulate the traction force of the suture during surgery.

[0113] After completing the modeling, finite element calculation is performed, and the calculation results of Abaqus are recorded to obtain the mechanical information corresponding to multiple candidate insertion directions.

[0114] Step 4: Select the preferred placement direction based on the finite element analysis results.

[0115] This specific embodiment uses the maximum stress of the suture anchor as a reference value. The maximum stress can reflect the stress distribution around the thread of the suture anchor. Small stress is more conducive to the fixation of the anchor. Therefore, the direction with the smallest maximum stress value is selected from the nine candidate insertion directions as the preferred insertion direction for preoperative planning.

[0116] This specific embodiment uses MIMICS software to perform MPR reconstruction on CT images, establishes a reference three-dimensional coordinate system based on preset anatomical feature points of the humerus, and records the coordinates of key points. The key points are restored using the 3D sketch function in SoldiesWorks, thereby reconstructing a unified distal humeral coordinate system. This makes it easier to describe the placement point and direction of the suture anchor, facilitating the optimization of elbow arthroscopic surgery. Furthermore, a unified coordinate system across different individual samples facilitates the study of more general biological laws. Furthermore, this specific embodiment employs the finite element method to computationally solve the anchor-humerus finite element model. By establishing finite element models of the suture anchor with different placement directions, the mechanical strength of the suture anchor under different placement directions is analyzed. The optimal placement direction of the suture anchor is determined based on the maximum thread stress of the suture anchor. This facilitates accurate preoperative planning, reduces the risk of the suture anchor penetrating the cortical bone, falling out, or entering the joint during surgery, and reduces postoperative surgical failures due to anchor loosening, displacement, or extraction. This method can not only improve the safety of elbow arthroscopic surgery, but also reduce the surgeon's dependence on arthroscopic surgical experience and reduce medical costs.

[0117] Figure 14 is a block diagram of a device for determining an elbow joint suture anchor placement direction according to an exemplary embodiment of the present disclosure. Figure 14 The device 1400 for determining the placement direction of an elbow joint suture anchor includes an acquisition unit 1401 , a coordinate construction unit 1402 , a model construction unit 1403 , a calculation unit 1404 , and a determination unit 1405 .

[0118] The acquisition unit 1401 may acquire three-dimensional image data and suture anchor data of the target patient's elbow joint.

[0119] The coordinate construction unit 1402 may construct a reference three-dimensional coordinate system based on preset anatomical feature points in the three-dimensional image data of the elbow joint.

[0120] The model construction unit 1403 can construct multiple elbow joint models with inserted anchors according to a reference three-dimensional coordinate system based on the elbow joint three-dimensional image data and the suture anchor data, wherein each elbow joint model with inserted anchors is used to represent the insertion of a suture anchor into the elbow joint of the target patient along a candidate insertion direction, and the multiple elbow joint models with inserted anchors correspond one-to-one to the multiple candidate insertion directions.

[0121] The calculation unit 1404 may perform mechanical analysis calculations on the multiple elbow joint models with the anchor pins placed therein, and obtain mechanical information corresponding to each elbow joint model with the anchor pins placed therein.

[0122] The determining unit 1405 may determine one of the multiple candidate implantation directions corresponding to the multiple elbow joint models with the implanted anchors as the preferred implantation direction based on the mechanical information corresponding to each of the multiple elbow joint models with the implanted anchors.

[0123] Optionally, the preset anatomical feature points include the apex of the medial epicondyle, the apex of the lateral epicondyle, the lowest point of the trochlear ridge, and the midpoint of the narrowest part of the distal humeral cortex. The coordinate construction unit 1402 can also: determine the straight line connecting the apex of the medial epicondyle and the apex of the lateral epicondyle as the X-axis of the reference three-dimensional coordinate system, determine the apex of the lateral epicondyle as the origin of the reference three-dimensional coordinate system, and determine the direction of the apex of the medial epicondyle as the positive direction of the X-axis; determine the plane perpendicular to the X-axis and passing through the lowest point of the trochlear ridge as the reference sagittal plane; determine the straight line parallel to the reference Z-axis in the reference sagittal plane and passing through the origin as the Z-axis of the reference three-dimensional coordinate system, and determine the straight line perpendicular to both the X-axis and the Z-axis as the Y-axis of the reference three-dimensional coordinate system, wherein the reference Z-axis is a straight line passing through the midpoint of the narrowest part of the distal humeral cortex in the reference sagittal plane and tangent to the innermost cortex of the humeral body; based on the right-hand rule, determine the positive directions of the Y-axis and the Z-axis according to the positive direction of the X-axis.

[0124] Optionally, the original three-dimensional coordinate system in the three-dimensional image data of the elbow joint includes an original horizontal plane, an original coronal plane, and an original sagittal plane. The coordinate construction unit 1402 can also: translate and rotate the original coronal plane and the original horizontal plane to obtain an adjusted coronal plane, an adjusted horizontal plane, and a corresponding adjusted sagittal plane, so that the intersection line of the adjusted coronal plane and the adjusted horizontal plane coincides with the X-axis; translate the adjusted sagittal plane in the adjusted coronal plane to pass through the lowest point of the trochlear crest to obtain a reference sagittal plane; and in the reference sagittal plane , translate and rotate the adjusted coronal plane to obtain a reference coronal plane, so that the reference coronal plane passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost cortex of the humeral body, and rotate the adjusted horizontal plane accordingly to obtain a reference horizontal plane; translate the reference horizontal plane, the reference coronal plane, and the reference sagittal plane until they intersect each other at the origin, and use the intersection line of the reference coronal plane and the reference sagittal plane after translation as the Z axis, and the intersection line of the reference horizontal plane and the reference sagittal plane after translation as the Y axis.

[0125] Optionally, the model construction unit 1403 may further: construct an elbow joint model based on the three-dimensional image data of the elbow joint; determine multiple candidate insertion directions in the three-dimensional space described by the reference three-dimensional coordinate system; for each candidate insertion direction, construct an elbow joint model in which the suture anchor is inserted into the elbow joint model along the candidate insertion direction based on the suture anchor data, thereby obtaining multiple elbow joint models in which the suture anchor is inserted.

[0126] Optionally, the reference three-dimensional coordinate system includes a horizontal plane, a coronal plane, and a sagittal plane that are perpendicular to each other, the intersection of the horizontal plane and the coronal plane being the X-axis of the reference three-dimensional coordinate system, the intersection of the horizontal plane and the sagittal plane being the Y-axis of the reference three-dimensional coordinate system, and the intersection of the coronal plane and the sagittal plane being the Z-axis of the reference three-dimensional coordinate system. The model construction unit 1403 may further: rotate the horizontal plane around the Y-axis by multiple first preset angles to obtain multiple rotated horizontal planes, and rotate the coronal plane around the Z-axis by multiple second preset angles to obtain multiple rotated coronal planes; determine the direction of the intersection of a rotated horizontal plane and a rotated coronal plane as a candidate implantation direction, and determine multiple candidate implantation directions based on the multiple rotated horizontal planes and the multiple rotated coronal planes.

[0127] Optionally, the positive direction of the Z axis is the direction from the distal end of the humerus to the proximal end of the humerus, and the angle of rotation of the horizontal plane around the Y axis toward the positive direction close to the Z axis is positive, and multiple first preset angles are all positive angles; multiple second preset angles include 0, positive angles and negative angles.

[0128] Regarding the apparatus in the above embodiment, the specific manner in which each unit performs operations has been described in detail in the embodiment of the method, and will not be elaborated on here.

[0129] Figure 15 15 is a block diagram showing a structure of an electronic device 1500 according to an exemplary embodiment of the present disclosure.

[0130] Reference Figure 15 The electronic device 1500 includes: at least one memory 1501 and at least one processor 1502, wherein the at least one memory 1501 stores computer executable instructions. When the computer executable instructions are executed by the at least one processor 1502, the at least one processor is prompted to execute the target corresponding method as described in the above exemplary embodiment.

[0131] As an example, the electronic device 1500 may be a PC, a tablet device, a personal digital assistant, a smart phone, or other device capable of executing the above-mentioned instruction set. Here, the electronic device 1500 is not necessarily a single electronic device 1500, but may also be any device or circuit that can execute the above-mentioned instructions (or instruction set) individually or in combination. The electronic device 1500 may also be part of an integrated control system or system manager, or may be configured as a portable electronic device 1500 that is interconnected with a local or remote (e.g., via wireless transmission) interface.

[0132] In electronic device 1500, processor 1502 may include a central processing unit (CPU), a graphics processing unit (GPU), a programmable logic device, a dedicated processor system, a microcontroller, or a microprocessor. By way of example and not limitation, processor 1502 may also include an analog processor, a digital processor, a microprocessor, a multi-core processor, a processor array, a network processor, etc.

[0133] The processor 1502 can execute instructions or codes stored in the memory 1501, wherein the memory 1501 can also store data. Instructions and data can also be sent and received over a network via a network interface device, wherein the network interface device can use any known transmission protocol.

[0134] Memory 1501 may be integrated with processor 1502, for example, by placing RAM or flash memory within an integrated circuit microprocessor or the like. Furthermore, memory 1501 may comprise a separate device, such as an external disk drive, a storage array, or any other storage device usable by a database system. Memory 1501 and processor 1502 may be operatively coupled or may communicate with each other, for example, via an I / O port, a network connection, or the like, such that processor 1502 can access files stored in memory.

[0135] In addition, the electronic device 1500 may further include a video display (such as a liquid crystal display) and a user interaction interface (such as a keyboard, a mouse, a touch input device, etc.) All components of the electronic device 1500 may be connected to each other via a bus and / or a network.

[0136] According to an exemplary embodiment of the present disclosure, a computer-readable storage medium storing instructions may also be provided, wherein the instructions, when executed by at least one processor, prompt the at least one processor to perform the target corresponding method as described in the above exemplary embodiment. Examples of computer-readable storage media here include: read-only memory (ROM), random access programmable read-only memory (PROM), electrically erasable programmable read-only memory (EEPROM), random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, non-volatile memory, CD-ROM, CD-R, CD+R, CD-RW, CD+RW, DVD-ROM, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, Blu-ray or optical disk storage, hard disk drive (HDD), solid state drive (SSD), card storage (such as, multimedia card, secure digital (SD) card or ultra-fast digital (XD) card), magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid state disk and any other device, any other device configured to store the computer program and any associated data, data files and data structures in a non-transitory manner and provide the computer program and any associated data, data files and data structures to a processor or computer so that the processor or computer can execute the computer program. The computer program in the above-mentioned computer-readable storage medium can be run in an environment deployed in a computer device such as a client, a host, an agent device, a server, etc. In addition, in one example, the computer program and any associated data, data files and data structures are distributed on a networked computer system so that the computer program and any associated data, data files and data structures are stored, accessed and executed in a distributed manner by one or more processors or computers.

[0137] According to an exemplary embodiment of the present disclosure, a computer program product may further be provided, including computer instructions. When the computer instructions are executed by at least one processor, the target corresponding method as described in the above exemplary embodiment is executed.

[0138] Other embodiments of the present disclosure will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

[0139] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A method for determining the placement direction of an elbow joint suture anchor, characterized in that: The determination method includes: Acquire three-dimensional imaging data and suture anchor data of the target patient's elbow joint; Based on the preset anatomical feature points in the three-dimensional image data of the elbow joint, a reference three-dimensional coordinate system is constructed, wherein the reference three-dimensional coordinate system includes a horizontal plane, a coronal plane, and a sagittal plane that are perpendicular to each other, the intersection of the horizontal plane and the coronal plane is the X-axis of the reference three-dimensional coordinate system, the intersection of the horizontal plane and the sagittal plane is the Y-axis of the reference three-dimensional coordinate system, and the intersection of the coronal plane and the sagittal plane is the Z-axis of the reference three-dimensional coordinate system; constructing an elbow joint model based on the three-dimensional image data of the elbow joint; Rotating the horizontal plane around the Y axis by a plurality of first preset angles to obtain a plurality of rotated horizontal planes, and rotating the coronal plane around the Z axis by a plurality of second preset angles to obtain a plurality of rotated coronal planes; determining a direction of an intersection line of a rotational horizontal plane and a rotational coronal plane as a candidate implantation direction, and determining a plurality of candidate implantation directions based on the plurality of rotational horizontal planes and the plurality of rotational coronal planes; For each candidate placement direction, constructing an elbow joint model of the suture anchor placed in the elbow joint model along the candidate placement direction based on the suture anchor data, thereby obtaining a plurality of elbow joint models of the suture anchor, wherein each elbow joint model of the suture anchor is used to represent placement of the suture anchor into the elbow joint of the target patient along one candidate placement direction, and the plurality of elbow joint models of the suture anchor correspond one-to-one to the plurality of candidate placement directions; Performing mechanical analysis and calculation on the multiple elbow joint models with anchor pins inserted, respectively, to obtain mechanical information corresponding to each elbow joint model with anchor pins inserted; According to the mechanical information corresponding to each of the plurality of elbow joint models with the anchors placed, one is determined from the plurality of candidate placement directions corresponding to the plurality of elbow joint models with the anchors placed as a preferred placement direction.

2. The determination method according to claim 1, wherein: The preset anatomical feature points include the apex of the medial epicondyle, the apex of the lateral epicondyle, the lowest point of the trochlear crest, and the midpoint of the narrowest part of the distal humeral cortex. The construction of a reference three-dimensional coordinate system based on the preset anatomical feature points in the three-dimensional image data of the elbow joint includes: Determine the straight line connecting the medial epicondyle vertex and the lateral epicondyle vertex as the X-axis of the reference three-dimensional coordinate system, determine the lateral epicondyle vertex as the origin of the reference three-dimensional coordinate system, and determine the direction where the medial epicondyle vertex is located as the positive direction of the X-axis; Determine a plane perpendicular to the X-axis and passing through the lowest point of the trochlear crest as a reference sagittal plane; Determine a straight line parallel to a reference Z axis in the reference sagittal plane and passing through the origin as the Z axis of the reference three-dimensional coordinate system, and determine a straight line perpendicular to both the X axis and the Z axis as the Y axis of the reference three-dimensional coordinate system, wherein the reference Z axis is a straight line in the reference sagittal plane passing through the midpoint of the narrowest part of the distal humeral cortex and tangent to the innermost cortex of the humeral body; Based on the right-hand rule, the positive directions of the Y axis and the Z axis are determined according to the positive direction of the X axis.

3. The determination method according to claim 2, wherein: The original three-dimensional coordinate system in the three-dimensional image data of the elbow joint includes an original horizontal plane, an original coronal plane and an original sagittal plane. Wherein, determining a plane perpendicular to the X-axis and passing through the lowest point of the trochlear crest as a reference sagittal plane comprises: translating and rotating the original coronal plane and the original horizontal plane to obtain an adjusted coronal plane, an adjusted horizontal plane, and a corresponding adjusted sagittal plane, so that an intersection line of the adjusted coronal plane and the adjusted horizontal plane coincides with the X-axis; In the adjusted coronal plane, translating the adjusted sagittal plane to pass through the lowest point of the trochlear crest to obtain the reference sagittal plane; The method of determining a straight line parallel to the reference Z axis in the reference sagittal plane and passing through the origin as the Z axis of the reference three-dimensional coordinate system, and determining a straight line perpendicular to both the X axis and the Z axis as the Y axis of the reference three-dimensional coordinate system, includes: In the reference sagittal plane, the adjusted coronal plane is translated and rotated to obtain a reference coronal plane, so that the reference coronal plane passes through the midpoint of the narrowest part of the distal humeral cortex and is tangent to the innermost cortex of the humeral body, and the adjusted horizontal plane is rotated accordingly to obtain a reference horizontal plane; The reference horizontal plane, the reference coronal plane, and the reference sagittal plane are translated until they intersect each other at the origin, the intersection line of the reference coronal plane and the reference sagittal plane after translation is determined as the Z axis, and the intersection line of the reference horizontal plane and the reference sagittal plane after translation is determined as the Y axis.

4. The determination method according to any one of claims 1 to 3, characterized in that: The positive direction of the Z axis is the direction from the distal end of the humerus to the proximal end of the humerus, and the angle of rotation of the horizontal plane around the Y axis toward the positive direction close to the Z axis is positive, and the multiple first preset angles are all positive angles; The plurality of second preset angles include 0, positive angles and negative angles.

5. A device for determining the insertion direction of an elbow joint suture anchor, characterized in that: The determining device comprises: an acquisition unit configured to acquire three-dimensional image data of an elbow joint and suture anchor data of a target patient; a coordinate construction unit configured to construct a reference three-dimensional coordinate system based on preset anatomical feature points in the three-dimensional image data of the elbow joint, wherein the reference three-dimensional coordinate system includes a horizontal plane, a coronal plane, and a sagittal plane that are perpendicular to each other, an intersection line of the horizontal plane and the coronal plane is an X-axis of the reference three-dimensional coordinate system, an intersection line of the horizontal plane and the sagittal plane is a Y-axis of the reference three-dimensional coordinate system, and an intersection line of the coronal plane and the sagittal plane is a Z-axis of the reference three-dimensional coordinate system; The model construction unit is configured to construct an elbow joint model based on the three-dimensional image data of the elbow joint; rotate the horizontal plane around the Y-axis by multiple first preset angles to obtain multiple rotated horizontal planes, and rotate the coronal plane around the Z-axis by multiple second preset angles to obtain multiple rotated coronal planes; determine the direction of the intersection of a rotated horizontal plane and a rotated coronal plane as a candidate insertion direction, and determine multiple candidate insertion directions based on the multiple rotated horizontal planes and the multiple rotated coronal planes; for each candidate insertion direction, construct an elbow joint model of the suture anchor placed in the elbow joint model along the candidate insertion direction based on the suture anchor data, to obtain multiple elbow joint models of the suture anchor placed, wherein each elbow joint model of the suture anchor placed is used to represent the insertion of a suture anchor into the elbow joint of the target patient along a candidate insertion direction, and the multiple elbow joint models of the suture anchor placed correspond one-to-one to the multiple candidate insertion directions; a computing unit configured to perform mechanical analysis and calculation on each of the plurality of elbow joint models implanted with anchor pins, and obtain mechanical information corresponding to each elbow joint model implanted with anchor pins; The determining unit is configured to determine one of the multiple candidate implantation directions corresponding to the multiple elbow joint models with the implanted anchors as a preferred implantation direction based on the mechanical information corresponding to each of the multiple elbow joint models with the implanted anchors.

6. An electronic device, characterized in that: include: at least one processor; at least one memory storing computer-executable instructions, Wherein, when the computer executable instructions are executed by the at least one processor, the at least one processor is prompted to execute the method for determining the placement direction of an elbow joint suture anchor according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that When the instructions in the computer-readable storage medium are executed by at least one processor, the instructions cause the at least one processor to perform the method for determining the placement direction of an elbow joint suture anchor according to any one of claims 1 to 4.

8. A computer program product comprising computer instructions, characterized in that When the computer instructions are executed by at least one processor, the computer instructions cause the at least one processor to perform the method for determining the placement direction of an elbow joint suture anchor according to any one of claims 1 to 4.

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