A method, system and device for testing the precision of TMC joint repair implants

Abstract

The present invention discloses a method, system and equipment for testing the fineness of a TMC joint repair implant, and the present invention relates to the technical field of printing object fineness testing. The method comprises the following steps: constructing a TMC joint finite element model based on the shape of the TMC joint implant; conducting a joint motion simulation test, collecting three-dimensional physical time series data at different temperatures, and identifying the change amplitude through a time series analysis algorithm; classifying the physical change amplitude, and if it meets the requirements, marking it as a non-temperature-affected implant; applying different contact forces to the implant for testing, collecting pressure response data, identifying synchronous pressure areas and their distribution; counting the number of synchronous pressure areas and the number of grid cells in each partition to characterize the force uniformity, and comparing with the uniformity threshold to judge the fineness of the TMC joint implant. Comprehensively and dynamically monitoring its physical performance improves the ability to evaluate fineness.

Description

Technical Field

[0001] The present invention relates to the technical field of fineness testing of printed objects, and in particular to a method, system and equipment for testing the fineness of a TMC joint repair implant. Background Art

[0002] The first trapezium-metacarpal (TMC) joint is located between the trapezium and the base of the first metacarpal. The TMC joint plays a crucial role in thumb function. Over the past decade, the use of mobile phones, other communication devices, and other handheld devices such as game controllers, tablets, iPads, and keyboards has increased. Today, text messaging is the most widely used mobile data service, with 2.4 billion of the 3.3 billion phone users actively using text messaging. Excessive use of the TMC can lead to excessive wear of the articular surfaces of the trapezium and metacarpal bones, and in severe cases, can lead to osteoarthritis and injury. Clinically, 3D-printed TMC implants, with their advantages of personalized design, good biocompatibility, and excellent mechanical properties, have been widely used in clinical surgery. 3D printing technology allows for customization based on individual anatomy, producing products that perfectly match natural bone structure. This minimizes the impact of implants (or prostheses) on the human body and maximizes the restoration of normal skeletal function.

[0003] The TMC joint allows three degrees of freedom of movement, including sagittal flexion and extension, frontal plane abduction and adduction, and a small amount of axial rotation in the horizontal plane. Based on these parameters, we can calculate the range of motion (ROM) of the TMC joint, which can be regarded as a necessary parameter related to TMC joint injury. Currently, there are friction and wear test tests on sample materials on the market that can test the wear performance of materials. Most of the sample shapes are regular pie-shaped, which is limited to the inability to simulate samples of different shapes. For TMC joint movement, its disadvantage is that it cannot accurately simulate the actual movement of the joint and the uniformity of surface force.

[0004] In the prior art, publication number CN108790177A discloses a method for testing the fineness of 3D printed objects, which includes the following steps: modeling: designing a test piece entity model, the outer side and top of the test piece entity model are provided with a plurality of test pattern models, the test pattern model includes a first and a second rectangular parallelepiped model vertically and evenly distributed along the X and Y axis directions; printing: printing a test piece entity according to the test piece entity model by SLA 3D printing technology, the outer side and top of the test piece entity are provided with test patterns, the test pattern includes a first rectangular parallelepiped model vertically and evenly distributed along the X and Y axis directions; The first and second cuboids are evenly distributed across the test pattern; measurement: the width, length and height of the first and second cuboids in the test pattern are measured by a test tool, and the data is recorded; comparative evaluation: the width, length and height measurement data of the first and second cuboids in the test pattern of the test piece entity are compared with the modeling data to evaluate the SLA3D printing precision. However, this scheme only judges the precision through static errors and does not involve the influence of errors during motion. Therefore, the precision of the TMC joint cannot be evaluated through this scheme, which will reduce the accuracy and effectiveness of the precision evaluation.

[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0006] The object of the present invention is to provide a method, system and equipment for testing the fineness of TMC joint repair implants to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for testing the fineness of a TMC joint repair implant comprises the following steps:

[0009] Based on the shape characteristic parameters of the TMC joint implant to be tested, a plurality of grid cells with a spatial topological structure are divided on the joint contact surface of the TMC joint implant to be tested, thereby constructing a TMC joint finite element model;

[0010] Setting test conditions with the same contact force but different operating temperatures, conducting joint motion simulation experiments on the finite element model based on each test condition, collecting three-dimensional physical time series data for each grid cell during the simulation test, and using a time series analysis algorithm to identify the magnitude of physical changes in the TMC joint implant under different operating temperatures based on the obtained three-dimensional physical time series data;

[0011] Based on the magnitude of the physical change of the TMC joint implant to be tested, the TMC joint implant to be tested is classified into a first-level category. If the magnitude of the physical change meets the joint motion requirements and the spatial changes of the displacement and strain data are continuous, the TMC joint implant to be tested is marked as a non-temperature-affected implant.

[0012] Set test conditions with the same temperature and different contact forces. Conduct joint motion simulation experiments on the finite element model marked as a temperature-independent implant based on each test condition. Collect pressure response data of each grid unit in the monitoring network under the corresponding contact force. Perform pressure partitioning on the simultaneous pressure response data, identify areas with similar pressure characteristics, and record them as synchronous pressure areas. Then traverse the pressure data of all grid units in the joint contact surface to determine the distribution of synchronous pressure areas.

[0013] The number of synchronous pressure areas on the joint contact surface and the number of grid units in each partition are obtained. The force uniformity of the TMC joint implant to be tested is characterized based on the obtained quantitative characteristics. A uniformity threshold is set, and the force uniformity of the TMC joint implant to be tested is compared with the uniformity threshold. Based on the comparison result, a judgment result of the fineness of the TMC joint implant to be tested is issued.

[0014] Furthermore, the shape characteristic parameters of the TMC joint implant to be tested include the joint contact surface area and the average curvature. The grid unit area size of the TMC joint finite element model is determined based on the shape characteristic parameters, wherein the specific area size of the grid unit is calculated based on the formula:

[0015]

[0016] Where, is the area of ​​the grid cell, is the standard value of the grid unit area, is the joint contact surface area of ​​the TMC joint implant to be tested, is the average curvature of the joint contact surface of the TMC joint implant to be tested, and are the standard values ​​of joint contact surface area and mean curvature, respectively.

[0017] Furthermore, a joint motion simulation test is performed on the deployed TMC joint implant to be tested. The joint motion simulation test specifically involves completing motion operations according to a set route through finite element analysis, and recording the three-dimensional physical time series data output by the TMC joint finite element model during the simulation test, including pressure time series data, strain time series data, and displacement time series data;

[0018] Based on the obtained three-dimensional physical time series data, the physical change amplitude of the TMC joint implant to be tested at different operating temperatures is identified through a time series analysis algorithm. The physical change amplitude of the TMC joint implant to be tested at different operating temperatures is calculated based on the formula:

[0019]

[0020] Where, is the magnitude of the physical change, It represents the physical change amplitude of the TMC joint implant to be tested at time t, is the starting time of a joint motion simulation test, is the end time of a joint motion simulation test, and t is the time variable during the joint motion simulation test;

[0021] in The calculation is based on the formula:

[0022]

[0023] Where, is the pressure difference of the qth grid cell at time t, is the strain difference of the qth grid element at time t, is the displacement difference of the qth grid cell at time t, where q is the index of the grid cell, corresponding to its unique digital identifier. ,in is the total number of grid cells;

[0024] The pressure difference of the qth grid cell The calculation is based on the formula:

[0025]

[0026] Where, is the total number of test temperatures, and is the index of the used temperature, It represents the pressure data of the qth grid unit at the rth operating temperature at time t. is the pressure data of the qth grid unit at the uth operating temperature at time t, Indicates the number of combinations of 2 temperatures selected from M test temperatures;

[0027] The average strain difference of the qth grid cell The calculation is based on the formula:

[0028]

[0029] Where, It represents the strain data of the qth grid unit at the rth operating temperature at time t. represents the strain data of the qth grid unit at the uth service temperature at time t;

[0030] The displacement difference of the qth grid cell The calculation is based on the formula:

[0031]

[0032] Where, is the displacement data of the qth grid unit at the rth operating temperature at time t, Represents the displacement data of the qth grid unit at the uth operating temperature at time t.

[0033] Furthermore, the specific logic for the first-level classification of the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested is as follows: first, determine whether the spatial changes of the displacement and strain data in each joint motion simulation test are continuous. If it is determined to be discontinuous, it is marked as a temperature-affected implant that does not meet the precision requirements. Otherwise, the next step of judgment is made based on the magnitude of its physical change. The specific judgment logic is as follows:

[0034] like When the TMC joint implant to be tested is judged to be a temperature-affected implant, it does not meet the precision requirements;

[0035] like When the TMC joint implant to be tested is judged to be a non-temperature-affected implant, it meets the precision requirements; is the first-level classification judgment threshold;

[0036] Among them, whether the spatial changes of displacement and strain data in each joint motion simulation test are continuous is determined by visual analysis or gradient calculation.

[0037] Furthermore, the pressure response data at the same moment are pressure partitioned, grid cells with similar pressure characteristics are identified, and the area formed by combining them is recorded as a synchronous pressure area, wherein the specific logic for determining the synchronous pressure area is as follows: randomly select a grid cell, extract the pressure response data of all grid cells at the corresponding moment in the joint motion simulation test, calculate the similarity between the pressure response data of the selected grid cell and the remaining grid cells at that moment, set the similarity range, traverse the pressure data of all grid cells in the joint contact surface, and classify the remaining grid cells that meet the similarity requirements as the pressure partition where the selected grid cell is located, and the area formed by all grid cells in the same pressure partition is recorded as the synchronous pressure area, and subsequently select the remaining grid cells for pressure partitioning, wherein the grid cells whose pressure partitions have been determined no longer participate in the selection step, and so on until the synchronous pressure area to which each grid cell belongs is determined, and the synchronous pressure area contains at least one grid cell;

[0038] The specific formula for calculating the similarity between the pressure response data of the selected grid cell and the remaining grid cells at this moment is:

[0039]

[0040] Where, At time t, the selected grid cell is The similarity of the pressure response data of each grid cell, is the pressure response data of the selected grid cell at time t, At time t, The pressure response data of grid cells, where The index of the grid cell corresponds to the unique numerical identifier set for each grid cell, where And i does not take the selected grid unit, where is the total number of grid cells;

[0041] The logic for classifying the remaining grid cells that meet the similarity requirements as the pressure zone where the selected grid cell is located is as follows:

[0042] like When judging The grid cells meet the similarity requirements and are classified into the same synchronous pressure area as the selected grid cell;

[0043] like When judging The grid cells do not meet the similarity requirements and do not belong to the same synchronous pressure area as the selected grid cell;

[0044] It is the pressure zone judgment threshold.

[0045] Furthermore, the force uniformity of the TMC joint implant to be tested is characterized based on the obtained quantitative characteristics, wherein the force uniformity is calculated based on the formula:

[0046]

[0047] Where, To test the uniformity of force on the TMC joint implant, is the average number of synchronous pressure areas of the tested TMC joint implant under different contact forces, is the average number of grid cells in the synchronous pressure region under the jth contact force, where j is the index of the contact force, , Set the total number of contact forces for the test, where and and are greater than 0, ;

[0048] The average number of synchronous pressure areas on the joint contact surface of the TMC joint implant under different contact forces is The specific calculation formula is:

[0049]

[0050] Where, Indicates the number of synchronous pressure areas at the yth detection moment, is the total number of selected detection moments, represents the detection moment randomly selected in the joint motion simulation test, and y is the index of the detection moment;

[0051] The number of synchronous pressure areas at time y The specific calculation formula is:

[0052]

[0053] Where, represents the number of synchronous pressure areas at the yth detection moment under the jth contact force;

[0054] Where, under the jth contact force, the average number of grid cells in the synchronous pressure area is The calculation is based on the formula:

[0055]

[0056] Where, is the mean number of grid cells in the synchronous pressure area at the yth detection moment under the jth contact force, where The calculation is based on the formula:

[0057]

[0058] Where, represents the number of grid cells in the bth synchronous pressure region at the yth detection moment under the jth contact force, where b is the index of the synchronous pressure region at the yth detection moment under the jth contact force, ;

[0059] Setting a uniformity threshold, comparing the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issuing a judgment result on the fineness of the TMC joint implant to be tested based on the comparison result;

[0060] The logic behind the specific precision judgment result is as follows:

[0061] like When the test is completed, the quality of the TMC joint implant to be tested is judged to be excellent and meets the precision requirements;

[0062] like When the TMC joint implant to be tested is judged to be of poor quality and does not meet the precision requirements, it will not be put into use;

[0063] The uniformity threshold is set.

[0064] The present invention also provides a fineness testing system for a TMC joint repair implant, wherein the fineness testing system for a TMC joint repair implant is used to perform the fineness testing method for a TMC joint repair implant, comprising:

[0065] A monitoring unit layout module is used to divide the joint contact surface of the TMC joint implant to be tested into a plurality of grid units with a spatial topological structure based on the shape characteristic parameters of the TMC joint implant to be tested, thereby constructing a TMC joint finite element model;

[0066] The temperature effect characterization module is used to set test conditions with the same contact force but different operating temperatures. Based on each test condition, the finite element model is subjected to joint motion simulation experiments. During the simulation test, 3D physical time series data of each grid cell is collected. Based on the obtained 3D physical time series data, a time series analysis algorithm is used to identify the magnitude of physical changes of the tested TMC joint implant at different operating temperatures.

[0067] a primary classification module for performing primary classification on the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested, and marking the TMC joint implant to be tested as a non-temperature-affected implant if the magnitude of the physical change meets the joint motion requirements and the spatial changes of the displacement and strain data are continuous;

[0068] The pressure attribution classification module is used to set test conditions with the same operating temperature and different contact forces. Based on each test condition, a joint motion simulation experiment is performed on the finite element model marked as a non-temperature-affected implant. The pressure response data of each grid unit in the monitoring network under the corresponding contact force is collected. The simultaneous pressure response data is pressure partitioned and regions with similar pressure characteristics are identified as synchronous pressure regions. The pressure data of all grid units in the joint contact surface are traversed to determine the distribution of synchronous pressure regions.

[0069] The precision judgment output module is used to obtain the number of synchronous pressure areas on the joint contact surface and the number of grid units in each partition, characterize the force uniformity of the TMC joint implant to be tested based on the obtained quantitative characteristics, set the uniformity threshold, compare the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issue a judgment result on the precision of the TMC joint implant to be tested based on the comparison result.

[0070] The present invention also provides a TMC joint repair implant fineness testing device, comprising one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned TMC joint repair implant fineness testing method.

[0071] Compared with the prior art, the present invention has the following beneficial effects:

[0072] This solution provides a precision testing method for TMC joint repair implants. By constructing a finite element model of grid cells, it can comprehensively and dynamically monitor the physical performance of the implant under various usage conditions, significantly improving the ability to evaluate implant performance. First, the establishment of a finite element analysis model ensures that the monitoring network covers the key areas of the joint contact surface and can collect multidimensional data including strain, pressure, and displacement in real time. This can obtain more detailed response characteristics of the implant under different temperature and contact force conditions, thereby better understanding the behavior of the implant in the real-world use environment.

[0073] Secondly, by performing time series analysis on the collected three-dimensional physical time series data, the magnitude of the physical changes of the implant at different temperatures can be identified. It is possible to accurately determine whether the implant is affected by temperature, thereby screening out implants with stable performance and that meet the requirements of joint motion. This classification mechanism effectively reduces the risk of using unqualified implants, fundamentally improving patient safety and comfort. In motion tests with different contact forces, this solution further enables in-depth analysis of pressure response data. By identifying areas with similar pressure characteristics through the pressure zoning method, the uniformity of force on the joint contact surface can be effectively evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 Schematic diagram of the overall method flow of the present invention;

[0075] Figure 2 Layout spatial structure diagram for grid cells;

[0076] Figure 3 This is the relationship diagram between force uniformity, synchronous pressure area and minimum number of grids;

[0077] Figure 4 Fitting curve of the minimum number of synchronous pressure areas and grid cells;

[0078] Figure 5 It is the synchronous pressure area-force uniformity fitting curve diagram;

[0079] Figure 6 Statistical point-line graph for fineness evaluation;

[0080] Figure 7 Schematic diagram of the overall system structure of the present invention. DETAILED DESCRIPTION

[0081] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0082] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0083] Example:

[0084] See also Figures 1-6 , the present invention provides a technical solution:

[0085] A method for testing the fineness of a TMC joint repair implant comprises the following steps:

[0086] Step 1: Based on the shape characteristic parameters of the TMC joint implant to be tested, a plurality of grid units with a spatial topological structure are divided on the joint contact surface of the TMC joint implant to be tested to construct a TMC joint finite element model.

[0087] Each grid cell has a unique digital identifier.

[0088] Based on the shape characteristic parameters of the TMC joint implant to be tested, a spatial topological structure of grid cells is determined on the joint contact surface of the TMC joint implant to be tested, wherein the shape characteristic parameters of the TMC joint implant to be tested include the size and average curvature of the joint contact surface.

[0089] The joint contact surface area can be precisely scanned using a 3D laser scanner or CT scanner. This technology can generate a high-resolution 3D model of the implant and calculate the actual joint contact surface area.

[0090] Based on the above-mentioned 3D scanning or CAD model acquisition, a curvature calculation tool is used to analyze the joint contact surface. Many 3D modeling software (such as Rhino, MATLAB, etc.) provide curvature calculation functions that can directly calculate the average curvature of the model surface. Through the analysis function of the software, a curvature distribution map is generated, and the average curvature value of the contact surface is extracted. In this embodiment, the joint finite element model and finite element analysis are disclosed in the paper "Optimization Design of Tibial Implants Based on Biomechanical Performance Analysis - Meng Ying". The method for establishing the finite element model of the TMC joint is similar and will not be repeated here.

[0091] The area size of the mesh unit of the TMC joint finite element model is determined based on the shape characteristic parameters, where the specific area size of the mesh unit is calculated based on the formula:

[0092]

[0093] Where, is the area of ​​the grid cell, is the standard value of the grid unit area, is the joint contact surface area of ​​the TMC joint implant to be tested, is the average curvature of the joint contact surface of the TMC joint implant to be tested, and are the standard values ​​of joint contact surface area and mean curvature, respectively.

[0094] It should be noted that the area of ​​the grid unit Specifically, the shape characteristic parameters of the TMC joint implant to be tested are adjusted, wherein the area of ​​the grid unit The larger the value, the larger the grid unit area and the sparser the grid of the monitoring network.

[0095] Among them, a larger contact surface means that the range of motion and contact area of ​​the joint become larger, and a larger grid cell area is required between grid cells to avoid overlap and ensure effective monitoring of the entire contact surface. This setting can help avoid data redundancy or signal interference caused by overly dense grid cells on a larger contact surface. Therefore, the area of ​​the grid cell is proportional to the size of the joint contact surface of the TMC joint implant to be tested. It indicates a proportional relationship, and the increase is determined by the difference from the standard value of the joint contact surface area.

[0096] The greater the curvature, the more curved or complex the shape of the joint contact surface. A denser grid cell arrangement may be required to accurately capture the dynamic changes of the joint in different positions and directions. A smaller grid cell area can help better cope with local stress concentration and physical changes, thereby providing more accurate monitoring data. Therefore, the area of ​​the grid cell is inversely proportional to the average curvature of the TMC joint implant to be tested. It represents an inverse relationship, and the increase is determined by the difference from the standard value of the joint contact surface area.

[0097] Table 1 shows some statistical data of the spatial coordinates of the grid unit layout, where the spatial coordinates specifically refer to the center coordinates of the grid unit.

[0098] Table 1: Statistics of grid cell spatial coordinates

[0099]

[0100] Step 2: Set test conditions with the same contact force and different operating temperatures. Perform joint motion simulation experiments on the finite element model based on each test condition. Collect three-dimensional physical timing data of each grid cell during the simulation test. Based on the obtained three-dimensional physical timing data, use a timing analysis algorithm to identify the physical change amplitude of the TMC joint implant to be tested at different operating temperatures.

[0101] Performing a joint motion simulation test on the deployed TMC joint implant to be tested. The joint motion simulation test specifically involves completing motion operations according to a set route through finite element analysis, and recording the three-dimensional physical time series data output by the TMC joint finite element model during the simulation test, including pressure time series data, strain time series data, and displacement time series data;

[0102] Based on the obtained three-dimensional physical time series data, the physical change amplitude of the TMC joint implant to be tested at different operating temperatures is identified through a time series analysis algorithm. The physical change amplitude of the TMC joint implant to be tested at different operating temperatures is calculated based on the formula:

[0103]

[0104] Where, is the magnitude of the physical change, It represents the physical change amplitude of the TMC joint implant to be tested at time t, is the starting time of a joint motion simulation test, is the end time of a joint motion simulation test, and t is the time variable during the joint motion simulation test;

[0105] It should be noted that the physical change amplitude in the entire joint motion simulation test is described in the form of integration.

[0106] in The calculation is based on the formula:

[0107]

[0108] Where, is the pressure difference of the qth grid cell at time t, is the strain difference of the qth grid element at time t, is the displacement difference of the qth grid cell at time t, where q is the index of the grid cell, corresponding to its unique digital identifier. ,in is the total number of grid cells;

[0109] It should be noted that the magnitude of the physical change at time t is described by integrating the pressure difference, strain difference, and displacement difference of each grid cell at time t.

[0110] The average pressure difference of the qth grid cell is The calculation is based on the formula:

[0111]

[0112] Where, is the total number of test temperatures, and is the index of the used temperature, It represents the pressure data of the qth grid unit at the rth operating temperature at time t. is the pressure data of the qth grid unit at the uth operating temperature at time t, Indicates the number of combinations of 2 temperatures selected from M test temperatures;

[0113] The strain difference of the qth grid cell The calculation is based on the formula:

[0114]

[0115] Where, It represents the strain data of the qth grid unit at the rth operating temperature at time t. represents the strain data of the qth grid unit at the uth service temperature at time t;

[0116] The displacement difference of the qth grid cell The calculation is based on the formula:

[0117]

[0118] Where, is the displacement data of the qth grid unit at the rth operating temperature at time t, Represents the displacement data of the qth grid unit at the uth operating temperature at time t.

[0119] It should be noted that, By comparing and analyzing the pressure differences at different temperatures in the same grid cell at the same time, Express the difference in pressure by using the index of temperature and Achieve pressure comparison at different temperatures, and To achieve the goal of not having the same or repeated temperature combination, and avoid repeated calculations, Determine the number of temperature combinations to calculate the average pressure difference. The average value represents the pressure difference of the qth grid cell at time t. The strain difference and displacement difference are similar and will not be elaborated here.

[0120] Step 3: Based on the physical change amplitude of the TMC joint implant to be tested, the TMC joint implant to be tested is classified into a primary category. If the physical change amplitude meets the joint motion requirements and the displacement and strain data spatial changes are continuous, the TMC joint implant to be tested is marked as a non-temperature-affected implant.

[0121] The specific logic for the first-level classification of the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested is as follows: First, determine whether the spatial changes of the displacement and strain data in each joint motion simulation test are continuous. If it is determined to be discontinuous, it is marked as a temperature-affected implant that does not meet the precision requirements. Otherwise, the next step of judgment is made based on the magnitude of the physical change. The specific judgment logic is as follows:

[0122] like When the TMC joint implant to be tested is judged to be a temperature-affected implant, it does not meet the precision requirements;

[0123] like When the TMC joint implant to be tested is judged to be a non-temperature-affected implant, it meets the precision requirements; is the first-level classification judgment threshold;

[0124] Among them, whether the spatial changes of displacement and strain data in each joint motion simulation test are continuous is determined by visual analysis or gradient calculation.

[0125] Steps to determine the continuity of displacement and strain: Obtain experimental data of displacement and strain from joint motion simulation tests, and ensure that the data covers the entire range of motion of the joint. Filter and denoise the experimental data to eliminate possible errors. The data needs to be evenly sampled in space to ensure the effectiveness of the analysis. Visualize the displacement and strain data (for example, using heat maps, surface plots, etc.) to observe the spatial trend of the data. Continuous displacement and strain should appear as smooth changes, rather than sudden changes or discrete jumps. Calculate the gradient of the displacement field. If the gradient is continuous within the region, it means that the displacement is continuous in space. For two-dimensional or three-dimensional displacement fields, calculate the partial derivatives of each component and use finite difference methods or interpolation methods to estimate the gradient.

[0126] Step 4: Set up test conditions with the same temperature and different contact forces. Based on each test condition, conduct joint motion simulation experiments on the finite element model marked as non-temperature-affected implants. Collect the pressure response data of each grid unit in the monitoring network under the corresponding contact force, perform pressure partitioning on the simultaneous pressure response data, identify areas with similar pressure characteristics, record them as synchronous pressure areas, traverse the pressure data of all grid units in the joint contact surface, and determine the distribution of synchronous pressure areas.

[0127] The pressure response data at the same moment are pressure partitioned, grid cells with similar pressure characteristics are identified, and the area formed by combining them is recorded as a synchronous pressure area, wherein the specific logic for determining the synchronous pressure area is as follows: a grid cell is randomly selected, and the pressure response data of all grid cells at the corresponding moment in the joint motion simulation test are extracted. The similarity between the pressure response data of the selected grid cell and the remaining grid cells at that moment is calculated, and a similarity range is set. The pressure data of all grid cells in the joint contact surface are traversed, and the remaining grid cells that meet the similarity requirements are classified as the pressure partition where the selected grid cell is located. The area formed by all grid cells in the same pressure partition is recorded as the synchronous pressure area. The remaining grid cells are subsequently selected for pressure partitioning, wherein the grid cells whose pressure partitions have been determined no longer participate in the selection step, and this process is repeated until the synchronous pressure area to which each grid cell belongs is determined, and the synchronous pressure area contains at least one grid cell.

[0128] The specific formula for calculating the similarity between the pressure response data of the selected grid cell and the remaining grid cells at this moment is:

[0129]

[0130] Where, At time t, the selected grid cell is The similarity of the pressure response data of each grid cell, is the pressure response data of the selected grid cell at time t, At time t, The pressure response data of grid cells, where The index of the grid cell corresponds to the unique numerical identifier set for each grid cell, where And i does not take the selected grid unit, where is the total number of grid cells;

[0131] It should be noted that the selected grid unit is the same as the Similarity of pressure response data of grid cells The larger the value, the closer the selected grid cell is to the The closer the pressure response data of the grid cells are, the more uniform the force is, and the better the performance and precision of the TMC joint implant to be tested.

[0132] The logic for classifying the remaining grid cells that meet the similarity requirements as the pressure zone where the selected grid cell is located is as follows:

[0133] like When judging The grid cells meet the similarity requirements and are classified into the same synchronous pressure area as the selected grid cell;

[0134] like When judging The grid cells do not meet the similarity requirements and do not belong to the same synchronous pressure area as the selected grid cell;

[0135] It is the pressure zone judgment threshold.

[0136] The pressure zone judgment threshold The specific details can be determined through expert scoring method.

[0137] Step 5: Obtain the number of synchronous pressure areas on the joint contact surface and the number of grid cells in each partition, characterize the force uniformity of the TMC joint implant to be tested based on the obtained quantitative characteristics, set a uniformity threshold, compare the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issue a judgment result on the fineness of the TMC joint implant to be tested based on the comparison result.

[0138] The force uniformity of the tested TMC joint implant is characterized based on the obtained quantitative characteristics, wherein the force uniformity is calculated based on the formula:

[0139]

[0140] Where, To test the uniformity of force on the TMC joint implant, is the average number of synchronous pressure areas of the tested TMC joint implant under different contact forces, is the average number of grid cells in the synchronous pressure region under the jth contact force, where j is the index of the contact force, , Set the total number of contact forces for the test, where and and are greater than 0, ;

[0141] The average number of synchronous pressure areas on the joint contact surface of the TMC joint implant under different contact forces is The specific calculation is based on the formula:

[0142]

[0143] Where, Indicates the number of synchronous pressure areas at the yth detection moment, is the total number of selected detection moments, represents the detection moment randomly selected in the joint motion simulation test, and y is the index of the detection moment;

[0144] The number of synchronous pressure areas at time y The specific calculation formula is:

[0145]

[0146] Where, represents the number of synchronous pressure areas at the yth detection moment under the jth contact force;

[0147] Where, under the jth contact force, the average number of grid cells in the synchronous pressure area is The calculation is based on the formula:

[0148]

[0149] Where, is the mean number of grid cells in the synchronous pressure area at the yth detection moment under the jth contact force, where The calculation is based on the formula:

[0150]

[0151] Where, represents the number of grid cells in the bth synchronous pressure region at the yth detection moment under the jth contact force, where b is the index of the synchronous pressure region at the yth detection moment under the jth contact force, ;

[0152] It should be noted that the force uniformity of the TMC joint implant to be tested The force uniformity of the TMC joint implant to be tested is characterized by the number of synchronous pressure areas and the number of grid cells within the synchronous pressure areas. A larger value indicates that the force on the TMC joint implant to be tested is more uniform during the joint movement process, indicating that the precision of the TMC joint implant to be tested is higher.

[0153] The presence of multiple synchronous pressure zones indicates that the pressure distribution on the joint contact surface may be more complex. Each zone may be subjected to different pressures, and this complexity will lead to greater unevenness in the overall force. Therefore, more pressure zones mean potential uneven distribution, which in turn reduces the uniformity of force. Therefore, the average number of synchronous pressure zones on the joint contact surface of the tested TMC joint implant under different contact forces is determined. Force uniformity with the TMC joint implant to be tested Inversely proportional, through Indicates an inverse relationship. The square root function is a nonlinear function that can effectively slow down the impact of quantity changes on the results. When increasing, use directly May lead to uneven force The sharp decrease with the increase of the number of regions is not in line with the actual situation. Using the square root can make this relationship smoother and avoid over-sensitivity.

[0154] The fewer the number of grid cells in the synchronous pressure area, the greater the force difference between the synchronous pressure area and the surrounding area, which leads to a smaller number of grid cells in the synchronous pressure area. Therefore, the force uniformity of the TMC joint implant to be tested is reflected by the number of grid cells in the synchronous pressure area, and is proportional to the minimum number of grid cells in all synchronous pressure areas.

[0155] The average value of the number of synchronous pressure regions is directly related to the complexity and uniformity of the force distribution. The more regions there are, the more places on the joint contact surface need to consider the pressure distribution, so its impact on the force uniformity is more significant. A higher number of synchronous pressure regions means that the pressure changes on the joint contact surface can be captured more finely. This is crucial for improving force uniformity. Although the number of grid cells in each synchronous pressure region is also important, its impact is local and mainly reflects the pressure state of that specific region. Therefore, setting and and are greater than 0, .

[0156] Setting a uniformity threshold, comparing the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issuing a judgment result on the fineness of the TMC joint implant to be tested based on the comparison result;

[0157] The logic behind the specific precision judgment result is as follows:

[0158] like When the test is completed, the quality of the TMC joint implant to be tested is judged to be excellent and meets the precision requirements;

[0159] like When the TMC joint implant to be tested is judged to be of poor quality and does not meet the precision requirements, it will not be put into use;

[0160] The uniformity threshold is set based on expert experience. Table 2 shows some statistical data on the precision judgment results of each TMC joint implant to be tested.

[0161] Table 2: Statistics of fineness judgment results

[0162]

[0163] See also Figure 7 The present invention also provides a fineness testing system for a TMC joint repair implant, wherein the fineness testing system for a TMC joint repair implant is used to perform the fineness testing method for a TMC joint repair implant, comprising:

[0164] A monitoring unit layout module is used to divide the joint contact surface of the TMC joint implant to be tested into a plurality of grid units with a spatial topological structure based on the shape characteristic parameters of the TMC joint implant to be tested, thereby constructing a TMC joint finite element model;

[0165] The temperature effect characterization module is used to set test conditions with the same contact force but different operating temperatures. Based on each test condition, the finite element model is subjected to joint motion simulation experiments. During the simulation test, 3D physical time series data of each grid cell is collected. Based on the obtained 3D physical time series data, a time series analysis algorithm is used to identify the magnitude of physical changes of the tested TMC joint implant at different operating temperatures.

[0166] a primary classification module for performing primary classification on the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested, and marking the TMC joint implant to be tested as a non-temperature-affected implant if the magnitude of the physical change meets the joint motion requirements and the spatial changes of the displacement and strain data are continuous;

[0167] The pressure attribution classification module is used to set test conditions with the same operating temperature and different contact forces. Based on each test condition, a joint motion simulation experiment is performed on the finite element model marked as a non-temperature-affected implant. The pressure response data of each grid unit in the monitoring network under the corresponding contact force is collected. The simultaneous pressure response data is pressure partitioned and regions with similar pressure characteristics are identified as synchronous pressure regions. The pressure data of all grid units in the joint contact surface are traversed to determine the distribution of synchronous pressure regions.

[0168] The precision judgment output module is used to obtain the number of synchronous pressure areas on the joint contact surface and the number of grid units in each partition, characterize the force uniformity of the TMC joint implant to be tested based on the obtained quantitative characteristics, set the uniformity threshold, compare the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issue a judgment result on the precision of the TMC joint implant to be tested based on the comparison result.

[0169] The present invention also provides a TMC joint repair implant fineness testing device, comprising one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned TMC joint repair implant fineness testing method.

[0170] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0171] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraints of the technical solution.

[0172] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, and may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment as needed.

[0173] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A method for testing the fineness of a TMC joint repair implant, characterized in that: The specific steps include: Based on the shape characteristic parameters of the TMC joint implant to be tested, a plurality of grid cells with a spatial topological structure are divided on the joint contact surface of the TMC joint implant to be tested, thereby constructing a TMC joint finite element model; Setting test conditions with the same contact force but different operating temperatures, conducting joint motion simulation experiments on the finite element model based on each test condition, collecting three-dimensional physical time series data for each grid cell during the simulation test, and using a time series analysis algorithm to identify the magnitude of physical changes in the TMC joint implant under different operating temperatures based on the obtained three-dimensional physical time series data; Based on the magnitude of the physical change of the TMC joint implant to be tested, the TMC joint implant to be tested is classified into a first-level category. If the magnitude of the physical change meets the joint motion requirements and the spatial changes of the displacement and strain data are continuous, the TMC joint implant to be tested is marked as a non-temperature-affected implant. Set test conditions with the same temperature and different contact forces. Conduct joint motion simulation experiments on the finite element model marked as a temperature-independent implant based on each test condition. Collect pressure response data of each grid unit in the monitoring network under the corresponding contact force. Perform pressure partitioning on the simultaneous pressure response data, identify areas with similar pressure characteristics, and record them as synchronous pressure areas. Then traverse the pressure data of all grid units in the joint contact surface to determine the distribution of synchronous pressure areas. The number of synchronous pressure areas on the joint contact surface and the number of grid units in each partition are obtained. The force uniformity of the TMC joint implant to be tested is characterized based on the obtained quantitative characteristics. A uniformity threshold is set, and the force uniformity of the TMC joint implant to be tested is compared with the uniformity threshold. Based on the comparison result, a judgment result of the fineness of the TMC joint implant to be tested is issued.

2. The method for testing the fineness of a TMC joint repair implant according to claim 1, characterized in that: The shape characteristic parameters of the TMC joint implant to be tested include the joint contact surface area and the average curvature. The grid unit area size of the TMC joint finite element model is determined based on the shape characteristic parameters, wherein the specific area size of the grid unit is calculated based on the formula: Where, is the area of ​​the grid cell, is the standard value of the grid unit area, is the joint contact surface area of ​​the TMC joint implant to be tested, is the average curvature of the joint contact surface of the TMC joint implant to be tested, and are the standard values ​​of joint contact surface area and mean curvature, respectively.

3. The method for testing the fineness of a TMC joint repair implant according to claim 2, characterized in that: Performing a joint motion simulation test on the deployed TMC joint implant to be tested. The joint motion simulation test specifically involves completing motion operations according to a set route through finite element analysis, and recording the three-dimensional physical time series data output by the TMC joint finite element model during the simulation test, including pressure time series data, strain time series data, and displacement time series data; Based on the obtained three-dimensional physical time series data, the physical change amplitude of the TMC joint implant to be tested at different operating temperatures is identified through a time series analysis algorithm. The physical change amplitude of the TMC joint implant to be tested at different operating temperatures is calculated based on the formula: Where, is the magnitude of the physical change, It represents the physical change amplitude of the TMC joint implant to be tested at time t, is the starting time of a joint motion simulation test, is the end time of a joint motion simulation test, and t is the time variable during the joint motion simulation test; in The calculation is based on the formula: Where, is the pressure difference of the qth grid cell at time t, is the strain difference of the qth grid element at time t, is the displacement difference of the qth grid cell at time t, where q is the index of the grid cell, corresponding to its unique digital identifier. ,in is the total number of grid cells; The average pressure difference of the qth grid cell is The calculation is based on the formula: Where, is the total number of test temperatures, and is the index of the used temperature, It represents the pressure data of the qth grid unit at the rth operating temperature at time t. is the pressure data of the qth grid unit at the uth operating temperature at time t, Indicates the number of combinations of 2 temperatures selected from M test temperatures; The strain difference of the qth grid cell The calculation is based on the formula: Where, It represents the strain data of the qth grid unit at the rth operating temperature at time t. represents the strain data of the qth grid unit at the uth service temperature at time t; The displacement difference of the qth grid cell The calculation is based on the formula: Where, is the displacement data of the qth grid unit at the rth operating temperature at time t, Represents the displacement data of the qth grid unit at the uth operating temperature at time t.

4. The method for testing the fineness of a TMC joint repair implant according to claim 3, characterized in that: The specific logic for the first-level classification of the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested is as follows: First, determine whether the spatial changes of the displacement and strain data in each joint motion simulation test are continuous. If it is determined to be discontinuous, it is marked as a temperature-affected implant that does not meet the precision requirements. Otherwise, the next step of judgment is made based on the magnitude of the physical change. The specific judgment logic is as follows: like When the TMC joint implant to be tested is judged to be a temperature-affected implant, it does not meet the precision requirements; like When the TMC joint implant to be tested is judged to be a non-temperature-affected implant, it meets the precision requirements; is the first-level classification judgment threshold; Among them, whether the spatial changes of displacement and strain data in each joint motion simulation test are continuous is determined by visual analysis or gradient calculation.

5. The method for testing the fineness of a TMC joint repair implant according to claim 4, characterized in that: The pressure response data at the same moment are pressure partitioned, grid cells with similar pressure characteristics are identified, and the area formed by combining them is recorded as a synchronous pressure area, wherein the specific logic for determining the synchronous pressure area is as follows: a grid cell is randomly selected, and the pressure response data of all grid cells at the corresponding moment in the joint motion simulation test are extracted. The similarity between the pressure response data of the selected grid cell and the remaining grid cells at that moment is calculated, and a similarity range is set. The pressure data of all grid cells in the joint contact surface are traversed, and the remaining grid cells that meet the similarity requirements are classified as the pressure partition where the selected grid cell is located. The area formed by all grid cells in the same pressure partition is recorded as the synchronous pressure area. The remaining grid cells are subsequently selected for pressure partitioning, wherein the grid cells whose pressure partitions have been determined no longer participate in the selection step, and this process is repeated until the synchronous pressure area to which each grid cell belongs is determined, and the synchronous pressure area contains at least one grid cell. The specific formula for calculating the similarity between the pressure response data of the selected grid cell and the remaining grid cells at this moment is: Where, At time t, the selected grid cell is The similarity of the pressure response data of each grid cell, is the pressure response data of the selected grid cell at time t, At time t, The pressure response data of grid cells, where The index of the grid cell corresponds to the unique numerical identifier set for each grid cell, where And i does not take the selected grid unit, where is the total number of grid cells; The logic for classifying the remaining grid cells that meet the similarity requirements as the pressure zone where the selected grid cell is located is as follows: like When judging The grid cells meet the similarity requirements and are classified into the same synchronous pressure area as the selected grid cell; like When judging The grid cells do not meet the similarity requirements and do not belong to the same synchronous pressure area as the selected grid cell; The threshold for judging the pressure zone.

6. The method for testing the fineness of a TMC joint repair implant according to claim 5, characterized in that: The force uniformity of the tested TMC joint implant is characterized based on the obtained quantitative characteristics, wherein the force uniformity is calculated based on the formula: Where, To test the uniformity of force on the TMC joint implant, is the average number of synchronous pressure areas of the tested TMC joint implant under different contact forces, is the average number of grid cells in the synchronous pressure region under the jth contact force, where j is the index of the contact force, , Set the total number of contact forces for the test, where and and are greater than 0, ; The average number of synchronous pressure areas on the joint contact surface of the TMC joint implant under different contact forces is The specific calculation formula is: Where, Indicates the number of synchronous pressure areas at the yth detection moment, is the total number of selected detection moments, represents the detection moment randomly selected in the joint motion simulation test, and y is the index of the detection moment; The number of synchronous pressure areas at time y The specific calculation formula is: Where, represents the number of synchronous pressure areas at the yth detection moment under the jth contact force; Where, under the jth contact force, the average number of grid cells in the synchronous pressure area is The calculation is based on the formula: Where, is the mean number of grid cells in the synchronous pressure area at the yth detection moment under the jth contact force, where The calculation is based on the formula: Where, represents the number of grid cells in the bth synchronous pressure region at the yth detection moment under the jth contact force, where b is the index of the synchronous pressure region at the yth detection moment under the jth contact force, ; Setting a uniformity threshold, comparing the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issuing a judgment result on the fineness of the TMC joint implant to be tested based on the comparison result; The logic behind the specific precision judgment result is as follows: like When the test is completed, the quality of the TMC joint implant to be tested is judged to be excellent and meets the precision requirements; like When the TMC joint implant to be tested is judged to be of poor quality and does not meet the precision requirements, it will not be put into use; The uniformity threshold is set.

7. A precision testing system for TMC joint repair implants, characterized by: The fineness testing system for a TMC joint repair implant is used to perform the fineness testing method for a TMC joint repair implant according to any one of claims 1 to 6, comprising: A monitoring unit layout module is used to divide the joint contact surface of the TMC joint implant to be tested into a plurality of grid units with a spatial topological structure based on the shape characteristic parameters of the TMC joint implant to be tested, thereby constructing a TMC joint finite element model; The temperature effect characterization module is used to set test conditions with the same contact force but different operating temperatures. Based on each test condition, the finite element model is subjected to joint motion simulation experiments. During the simulation test, 3D physical time series data of each grid cell is collected. Based on the obtained 3D physical time series data, a time series analysis algorithm is used to identify the magnitude of physical changes of the tested TMC joint implant at different operating temperatures. a primary classification module for performing primary classification on the TMC joint implant to be tested based on the magnitude of the physical change of the TMC joint implant to be tested, and marking the TMC joint implant to be tested as a non-temperature-affected implant if the magnitude of the physical change meets the joint motion requirements and the spatial changes of the displacement and strain data are continuous; The pressure attribution classification module is used to set test conditions with the same operating temperature and different contact forces. Based on each test condition, a joint motion simulation experiment is performed on the finite element model marked as a non-temperature-affected implant. The pressure response data of each grid unit in the monitoring network under the corresponding contact force is collected. The simultaneous pressure response data is pressure partitioned and regions with similar pressure characteristics are identified as synchronous pressure regions. The pressure data of all grid units in the joint contact surface are traversed to determine the distribution of synchronous pressure regions. The precision judgment output module is used to obtain the number of synchronous pressure areas on the joint contact surface and the number of grid units in each partition, characterize the force uniformity of the TMC joint implant to be tested based on the obtained quantitative characteristics, set the uniformity threshold, compare the force uniformity of the TMC joint implant to be tested with the uniformity threshold, and issue a judgment result on the precision of the TMC joint implant to be tested based on the comparison result.

8. A precision testing device for TMC joint repair implants, characterized by: It comprises one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement a fineness testing method for a TMC joint repair implant as described in any one of claims 1 to 6.

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