Orthopedic surgery tool arrangement optimization method based on noise error propagation

Abstract

The invention discloses an orthopedic surgery tool arrangement optimization method based on noise error propagation, which comprehensively considers the influence of multi-source errors of a probe, a reference frame, a swing saw and the like on the final osteotomy precision by establishing a unified error propagation model. The method comprises the following steps: firstly, constructing a coordinate system model of a surgical tool and image data; then simulating a random measurement error in the acquisition process through a Monte Carlo framework, and calculating propagation of the error in a coordinate system pose chain based on a rigid body transformation algorithm; thirdly, counting osteotomy position errors and angle errors under multiple times of simulation; and finally, optimizing different surgical tool arrangement schemes by using weighted evaluation indexes. According to the method, the influence of the tool arrangement mode on the operation precision can be quantitatively evaluated, the error accumulation effect is remarkably reduced through scientific optimization and screening, and the accuracy and safety of the orthopedic operation are improved.

Description

Technical Field

[0001] This invention relates to the technical field of precision optimization and error simulation of orthopedic surgical tools, and in particular to a method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation, which is used in orthopedic robot-assisted surgery, especially for error propagation and correction during the calibration process of surgical tools. Background Technology

[0002] With the development of robot-assisted surgery and optical guidance technology, the precise positioning of orthopedic surgical tools has become a key factor affecting surgical outcomes and safety. However, existing technologies mainly focus on compensating for single error sources, neglecting the combined impact of multiple error sources on positioning accuracy. This results in significant final positioning errors, failing to meet the requirements of high-precision surgery.

[0003] Most existing orthopedic surgical tool positioning systems rely on traditional calibration methods, typically using single-point calibration or a reference calibration point to correct errors. However, these methods cannot comprehensively improve accuracy when faced with complex environments and multi-source errors. Furthermore, while existing error propagation analysis methods can compensate for some error sources, they lack systematic analysis of multi-source error propagation paths and do not consider how to further reduce errors by optimizing the arrangement of surgical tools.

[0004] Therefore, how to systematically calculate and optimize the positioning error of orthopedic surgical tools during the calibration and surgical process, especially by reducing error propagation through error propagation models and arrangement optimization, has become an important issue in improving the positioning accuracy of surgical tools. Summary of the Invention

[0005] The purpose of this invention is to provide an orthopedic surgical tool arrangement optimization method based on noise error propagation, which can comprehensively consider the propagation and influence of multi-source errors, optimize the arrangement scheme of surgical tool markers, thereby minimizing errors and improving the tool positioning accuracy in robot-assisted surgical systems.

[0006] To achieve the above objectives, the technical solution provided by this invention is: a method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation, comprising the following steps:

[0007] S1. Prepare the geometric model data of the surgical tools, including the measurement parameters of the probe tool, femoral reference frame, and oscillating saw. Unify the modeling of the probe tool marker points, bone CT image point cloud, CT image-planned osteotomy path, femoral reference frame marker points, oscillating saw reference frame marker points, noise parameters, and simulation times, and then establish the probe tool coordinate system. Femoral reference frame coordinate system oscillating saw reference frame coordinate system With CT image coordinate system And the coordinate system of the optical positioning instrument is regarded as the world coordinate system. This yields the relationship between the initial dataset and the coordinate system;

[0008] S2. To simulate measurement errors during the data acquisition process, the world coordinate system is directly used. Bone surface dot cloud Noise is injected and modeled, and the probe tool coordinate system is estimated based on rigid body transformation. To the world coordinate system World coordinate system To the femoral reference frame coordinate system The pose chain calculation will be performed using the probe tool coordinate system. Bone surface dot cloud Switch to femoral reference frame coordinate system The femoral reference frame coordinate system is obtained. Bone surface dot cloud With pose chain;

[0009] S3. Adjust the femoral reference frame coordinate system Bone surface dot cloud Point cloud of bone CT images Perform registration to obtain the CT image coordinate system. To the femoral reference frame coordinate system The registration results were obtained, and the osteotomy path point pairs planned from CT images were converted into the femoral reference frame coordinate system. The target operation direction point is correct;

[0010] S4. Adjust the femoral reference frame coordinate system Target operation direction point pair mapped to world coordinate system Noise is injected into the reference frame markers of the oscillating saw, and the oscillating saw is calculated to the world coordinate system. The position of the oscillating saw is determined according to the principle of direction alignment, so that the actual operation direction point of the oscillating saw is consistent with the target operation direction point, thereby enabling the oscillating saw to realize the osteotomy path planned by CT image.

[0011] S5. Repeat the above steps S2-S4 under the Monte Carlo framework according to the number of simulations, and statistically analyze the positional and angular errors between the planned osteotomy path points in CT images and the oscillating saw execution direction to form error index and error distribution data.

[0012] S6. Based on the error index set and error distribution data, compare and evaluate the candidate surgical tool arrangement schemes, and select the surgical tool arrangement scheme with the smallest error to ensure the final positioning accuracy of the surgical tools.

[0013] Furthermore, in step S1, the input data of probe tool marker points, femoral reference frame marker points, oscillating saw reference frame marker points, bone CT image point cloud, and CT image-planned osteotomy path are preprocessed, and then the probe tool coordinate system is established. Femoral reference frame coordinate system oscillating saw reference frame coordinate system With CT image coordinate system And the coordinate system of the optical positioning instrument is regarded as the world coordinate system. This process yields a standardized coordinate system and geometric relationships. During preprocessing, all data is normalized to ensure that the input dataset maintains a consistent scale, facilitating subsequent coordinate system transformation and point cloud registration operations.

[0014] Furthermore, in step S2, the influence of multi-source errors during the surgical procedure is simulated by introducing noise. Specifically, this involves obtaining the probe tool coordinate system. Points on the femoral surface were used to obtain a point cloud of the bone surface. Then, the coordinate system is transformed using the following formula:

[0015] ;

[0016] In the formula, World coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system To the world coordinate system The transformation matrix;

[0017] The pose calculation process of the optical positioning instrument is simulated by using a rigid body transformation algorithm based on the probe tool marker points. The above conversion provides a reliable geometric reference for subsequent error propagation calculations.

[0018] When simulating errors, the bone surface point cloud introduces noise in a Gaussian distribution to reflect the actual situation of equipment and positioning errors. The noise introduction model is shown below:

[0019] ;

[0020] In the formula, The noise model is Gaussian. The standard deviation of the noise is given by the bone surface point cloud obtained after noise simulation. The aforementioned noise introduction ensures the reasonable simulation of multi-source errors during the simulation process and provides a basis for subsequent error propagation analysis.

[0021] Based on the femoral reference frame markers, the world coordinate system is calculated using a rigid body transformation algorithm. To the femoral reference frame coordinate system Transformation matrix This allows the bone surface point cloud obtained after noise simulation to be transformed. Transform to femoral reference frame coordinate system Below, the femoral reference frame coordinate system is obtained. Bone surface dot cloud The specific point cloud transformation formula is as follows:

[0022] .

[0023] Furthermore, in step S3, the SVD registration algorithm is used to generate CT image point clouds. With femoral reference frame coordinate system Bone surface dot cloud Registration yields the CT image coordinate system. To the femoral reference frame coordinate system Transformation matrix ;

[0024] Then through the CT image coordinate system To the femoral reference frame coordinate system Transformation matrix CT images are used to plan osteotomy pathway points and Converted to femoral reference frame coordinate system The target operation direction point below and This is used to guide the oscillating saw for subsequent osteotomy. The specific formula is as follows:

[0025] .

[0026] Furthermore, in step S4, the world coordinate system is first... To the femoral reference frame coordinate system Transformation matrix Perform an inverse transformation to obtain the femoral reference frame coordinate system. To the world coordinate system Transformation matrix And through the transformation matrix The femoral reference frame coordinate system Target operation direction point pair and Convert to world coordinate system Target operation direction point pair and The projection formula is as follows:

[0027] ;

[0028] Next, noise is introduced to simulate the oscillating saw error, and based on the marked points of the oscillating saw reference frame, a rigid body transformation algorithm is used to calculate the error from the oscillating saw reference frame coordinate system. Transform to world coordinate system Transformation matrix Align the actual operating direction point of the oscillating saw with the coordinate system of the oscillating saw reference frame. Transform to world coordinate system :

[0029] ;

[0030] In the formula, and It is the coordinate system of the oscillating saw reference frame. The actual operating direction of the swing saw is correct. and World coordinate system The actual operating direction of the swing saw is correct;

[0031] Then, based on the orientation alignment principle, determine the execution pose of the oscillating saw, and set the world coordinate system... The actual operating direction of the swing saw is correct. and , and the world coordinate system Target operation direction point pair and Alignment allows the oscillating saw to plan the osteotomy path based on CT images.

[0032] Furthermore, in step S5, the world coordinate system is... The actual operating direction of the swing saw is correct. and Through the world coordinate system To the femoral reference frame coordinate system Transformation matrix The femoral reference frame coordinate system is obtained by transformation. The actual operating direction of the swing saw is... and ;

[0033] Then apply the transformation matrix Perform inverse transformation to obtain the femoral reference frame coordinate system To CT image coordinate system Transformation matrix By transforming the matrix The femoral reference frame coordinate system The actual operating direction of the swing saw is... and Switch to CT image coordinate system The actual operation direction point is obtained below. and ;

[0034] By calculating the osteotomy path point pairs based on CT images and With CT image coordinate system The actual operation direction point below and Positional error D and angular error between As error indicators, position error D and angle error Calculated using the following formula:

[0035] ;

[0036] ;

[0037] In the formula, It is a CT image-based osteotomy path planning point pair and The direction vector formed CT image coordinate system The actual operation direction point below and The direction vector is formed; the position error is calculated. and angle error It can assess the accuracy of tool arrangement and provide error distribution data for subsequent optimization processes.

[0038] Furthermore, in step S6, in order to comprehensively evaluate error indices of different dimensions, the specific process of comparison and evaluation is as follows: Setting position error... Weighting coefficients and angle error Weighting coefficients Using formulas Calculate the comprehensive error evaluation value for each candidate surgical tool arrangement scheme. The comprehensive error evaluation value of all candidate surgical tool arrangement schemes is compared. Select the comprehensive error evaluation value The smallest possible arrangement is chosen as the final surgical tool arrangement.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] 1. Comprehensive consideration of multi-source errors in orthopedic surgery: Unlike most existing technologies that only focus on compensating for a single error source, the surgical tool arrangement optimization method proposed in this invention can comprehensively consider multi-source errors (such as sensor errors, tool positioning errors, oscillating saw errors, etc.) and perform optimal accuracy calculations. This innovation effectively analyzes the propagation path of errors at each stage of orthopedic surgery, providing more accurate theoretical support for optimizing the arrangement of surgical tools.

[0041] 2. Optimization of the arrangement of orthopedic surgical tools: In the existing technology, most methods use traditional calibration methods to correct errors. However, this invention optimizes the arrangement of the marker points of orthopedic surgical tools. Based on error propagation analysis and simulation, it designs the optimal tool arrangement, which significantly improves the positioning accuracy in orthopedic surgery and reduces the cumulative effect of error propagation.

[0042] 3. Improve the positioning accuracy and safety of orthopedic surgery: This invention can effectively minimize positioning errors, especially in orthopedic surgeries with high precision requirements such as spinal, joint and fracture repair, and provides a significant improvement in positioning accuracy.

[0043] 4. Calibration and Idling Saw Error Correction: Unlike existing technologies, this invention not only focuses on optimizing tool arrangement but also analyzes the impact of transformation matrix errors and oscillating saw errors on tool positioning. By analyzing the error propagation path during calibration and considering the influence of errors in oscillating saw operation, this invention can assess the impact of these errors on the final tool positioning, thereby optimizing tool arrangement and reducing positioning deviations caused by these errors.

[0044] 5. Wide applicability and flexibility: The orthopedic surgical tool arrangement optimization method provided by this invention is not limited to specific types of orthopedic surgery. Most robot-assisted surgical systems, optically guided surgical tools, and medical image-guided systems can apply this method, which has strong versatility and adaptability. Attached Figure Description

[0045] Figure 1 This is a flowchart illustrating the overall process of the method of the present invention.

[0046] Figure 2 This is a schematic diagram of the preset coordinate system.

[0047] Figure 3 This is a schematic diagram of the transformation of bone surface point cloud in the world coordinate system and the femoral reference frame coordinate system.

[0048] Figure 4 This is a schematic diagram for calculating the error of the surgical oscillating saw. Detailed Implementation

[0049] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0050] This embodiment discloses a method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation, such as... Figure 1 As shown, the specific details are as follows:

[0051] S1. Prepare the geometric model data of the surgical instruments, including the measurement parameters of the probe tool, femoral reference frame, and oscillating saw. Unify the modeling of probe tool marker points, bone CT image point clouds, CT image-planned osteotomy path, femoral reference frame marker points, oscillating saw reference frame marker points, noise parameters, and simulation iterations. For example... Figure 2 As shown, a probe tool coordinate system is then established. Femoral reference frame coordinate system oscillating saw reference frame coordinate system With CT image coordinate system And the coordinate system of the optical positioning instrument is regarded as the world coordinate system. This process yields the initial dataset and coordinate system relationship. In this step, all the input data are preprocessed: the data is normalized to ensure that the input dataset maintains a consistent scale, which facilitates subsequent coordinate system transformation and point cloud registration operations.

[0052] S2. To simulate measurement errors during the data acquisition process, the world coordinate system is directly used. Bone surface dot cloud Noise is injected and modeled, specifically by introducing a noise model that follows a Gaussian distribution, as shown in the following formula:

[0053] ;

[0054] In the formula, World coordinate system The lower bone surface dotted with clouds, The noise model is Gaussian. The standard deviation of the noise is given by the bone surface point cloud obtained after noise simulation. .

[0055] The probe tool coordinate system is estimated based on rigid body transformation. To the world coordinate system World coordinate system To the femoral reference frame coordinate system Pose chain calculation, such as Figure 3 As shown, the probe tool coordinate system is specifically determined using the following formula. Bone surface dot cloud Transform to world coordinate system:

[0056] ;

[0057] In the formula, World coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system To the world coordinate system The transformation matrix.

[0058] The world coordinate system is calculated using a rigid body transformation algorithm. To the femoral reference frame coordinate system Transformation matrix The bone surface point cloud obtained after noise simulation Transform to the femoral reference frame coordinate system to obtain the femoral reference frame coordinate system. Bone surface dot cloud The specific point cloud transformation formula is as follows:

[0059] ;

[0060] S3. Adjust the femoral reference frame coordinate system Bone surface dot cloud Point cloud of bone CT images The SVD registration algorithm was used for registration to obtain the CT image coordinate system. To the femoral reference frame coordinate system Transformation matrix And the osteotomy path points were planned using CT images. and Converted to femoral reference frame coordinate system Target operation direction point and The specific formula is as follows:

[0061] ;

[0062] S4. Adjust the femoral reference frame coordinate system Target operation direction point pair mapped to world coordinate system The projection formula is as follows:

[0063] ;

[0064] In the formula, and World coordinate system The target operation direction point is correct. For the femoral reference frame coordinate system To the world coordinate system The transformation matrix, and For the femoral reference frame coordinate system The target operation direction point is correct.

[0065] Noise is injected into the reference frame markers of the oscillating saw, and the oscillating saw is calculated to the world coordinate system. The pose conversion formula is as follows:

[0066] ;

[0067] In the formula, and It is the coordinate system of the oscillating saw reference frame. The actual operating direction of the swing saw is correct. and World coordinate system The actual operating direction of the swing saw is correct. For the reference frame coordinate system of the oscillating saw Transform to world coordinate system The transformation matrix.

[0068] Then, based on the orientation alignment principle, determine the execution pose of the oscillating saw, and set the world coordinate system... The actual operating direction of the swing saw is correct. and , and the world coordinate system Target operation direction point pair and Alignment allows the oscillating saw to plan the osteotomy path based on CT images.

[0069] S5. Repeat steps S2-S4 under the Monte Carlo framework, performing the same number of simulations. Statistically analyze the positional and angular errors between the planned osteotomy path points on CT images and the oscillating saw's execution direction, generating error indices and error distribution data. Figure 4 As shown, the details are as follows:

[0070] world coordinate system The actual operating direction of the swing saw is correct. and Through the world coordinate system To the femoral reference frame coordinate system Transformation matrix The femoral reference frame coordinate system is obtained by transformation. The actual operating direction of the swing saw is... and ;

[0071] Then apply the transformation matrix Perform inverse transformation to obtain the femoral reference frame coordinate system To CT image coordinate system Transformation matrix By transforming the matrix The femoral reference frame coordinate system The actual operating direction of the swing saw is... and Switch to CT image coordinate system The actual operation direction point is obtained below. and ;

[0072] By calculating the osteotomy path point pairs based on CT images and With CT image coordinate system The actual operation direction point below and Positional error D and angular error between As error indicators, position error D and angle error Calculated using the following formula:

[0073] ;

[0074] ;

[0075] In the formula, It is a CT image-based osteotomy path planning point pair and The direction vector formed CT image coordinate system The actual operation direction point below and The direction vector is formed; the position error is calculated. and angle error It can assess the accuracy of tool arrangement and provide error distribution data for subsequent optimization processes.

[0076] S6. Based on error indices and error distribution data, the candidate surgical tool arrangement schemes are compared and evaluated. To comprehensively evaluate error indices of different dimensions, the specific process of comparison and evaluation is as follows: Positional error is set. Weighting coefficients and angle error Weighting coefficients Using formulas Calculate the comprehensive error evaluation value for each candidate surgical tool arrangement scheme. The comprehensive error evaluation value of all candidate surgical tool arrangement schemes is compared. Select the comprehensive error evaluation value The smallest possible arrangement is chosen as the final surgical tool arrangement.

[0077] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation, characterized in that, Includes the following steps: S1. Prepare the geometric model data of the surgical tools, including the measurement parameters of the probe tool, femoral reference frame, and oscillating saw. Unify the modeling of the probe tool marker points, bone CT image point cloud, CT image-planned osteotomy path, femoral reference frame marker points, oscillating saw reference frame marker points, noise parameters, and simulation times, and then establish the probe tool coordinate system. Femoral reference frame coordinate system oscillating saw reference frame coordinate system With CT image coordinate system And the coordinate system of the optical positioning instrument is regarded as the world coordinate system. This yields the relationship between the initial dataset and the coordinate system; S2. To simulate measurement errors during the data acquisition process, the world coordinate system is directly used. Bone surface dot cloud Noise is injected and modeled, and the probe tool coordinate system is estimated based on rigid body transformation. To the world coordinate system World coordinate system To the femoral reference frame coordinate system The pose chain calculation will be performed using the probe tool coordinate system. Bone surface dot cloud Switch to femoral reference frame coordinate system The femoral reference frame coordinate system is obtained. Bone surface dot cloud With pose chain; S3. Adjust the femoral reference frame coordinate system Bone surface dot cloud Point cloud of bone CT images Perform registration to obtain the CT image coordinate system. To the femoral reference frame coordinate system The registration results were obtained, and the osteotomy path point pairs planned from CT images were converted into the femoral reference frame coordinate system. The target operation direction point is correct; S4. Adjust the femoral reference frame coordinate system Target operation direction point pair mapped to world coordinate system Noise is injected into the reference frame markers of the oscillating saw, and the oscillating saw is calculated to the world coordinate system. The position of the oscillating saw is determined according to the principle of direction alignment, so that the actual operation direction point of the oscillating saw is consistent with the target operation direction point, thereby enabling the oscillating saw to realize the osteotomy path planned by CT image. S5. Repeat the above steps S2-S4 under the Monte Carlo framework according to the number of simulations, and statistically analyze the positional and angular errors between the planned osteotomy path points in CT images and the oscillating saw execution direction to form error index and error distribution data. S6. Based on the error index and error distribution data, compare and evaluate the candidate surgical tool arrangement schemes, and select the surgical tool arrangement scheme with the smallest error to ensure the final positioning accuracy of the surgical tools.

2. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 1, characterized in that, In step S1, the input data of probe tool marker points, femoral reference frame marker points, oscillating saw reference frame marker points, bone CT image point cloud, and CT image-planned osteotomy path are preprocessed, and then the probe tool coordinate system is established. Femoral reference frame coordinate system oscillating saw reference frame coordinate system With CT image coordinate system And the coordinate system of the optical positioning instrument is regarded as the world coordinate system. This process yields a standardized coordinate system and geometric relationships. During preprocessing, all data is normalized to ensure that the input dataset maintains a consistent scale, facilitating subsequent coordinate system transformation and point cloud registration operations.

3. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 2, characterized in that, In step S2, the influence of multi-source errors during surgery is simulated by introducing noise. Specifically, the probe tool coordinate system is obtained. Points on the femoral surface were used to obtain a point cloud of the bone surface. Then, the coordinate system is transformed using the following formula: ； In the formula, World coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system The lower bone surface dotted with clouds, For the probe tool coordinate system To the world coordinate system The transformation matrix; The pose calculation process of the optical positioning instrument is simulated by using a rigid body transformation algorithm based on the probe tool marker points. The above conversion provides a reliable geometric reference for subsequent error propagation calculations. When simulating errors, the bone surface point cloud introduces noise in a Gaussian distribution to reflect the actual situation of equipment and positioning errors. The noise introduction model is shown below: ； In the formula, The noise model is Gaussian. The standard deviation of the noise is given by the bone surface point cloud obtained after noise simulation. The aforementioned noise introduction ensures the reasonable simulation of multi-source errors during the simulation process and provides a basis for subsequent error propagation analysis. Based on the femoral reference frame markers, the world coordinate system is calculated using a rigid body transformation algorithm. To the femoral reference frame coordinate system Transformation matrix This allows the bone surface point cloud obtained after noise simulation to be transformed. Transform to femoral reference frame coordinate system Below, the femoral reference frame coordinate system is obtained. Bone surface dot cloud The specific point cloud transformation formula is as follows: 。 4. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 3, characterized in that, In step S3, the SVD registration algorithm is used to generate CT image point clouds. With femoral reference frame coordinate system Bone surface dot cloud Registration yields the CT image coordinate system. To the femoral reference frame coordinate system Transformation matrix ; Then through the CT image coordinate system To the femoral reference frame coordinate system Transformation matrix CT images are used to plan osteotomy pathway points and Converted to femoral reference frame coordinate system The target operation direction point below and This is used to guide the oscillating saw for subsequent osteotomy. The specific formula is as follows: 。 5. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 4, characterized in that, In step S4, first set the world coordinate system To the femoral reference frame coordinate system Transformation matrix Perform an inverse transformation to obtain the femoral reference frame coordinate system. To the world coordinate system Transformation matrix And through the transformation matrix femoral reference frame coordinate system Target operation direction point pair and Convert to world coordinate system Target operation direction point pair and The projection formula is as follows: ； Next, noise is introduced to simulate the oscillating saw error, and based on the marked points of the oscillating saw reference frame, a rigid body transformation algorithm is used to calculate the error from the oscillating saw reference frame coordinate system. Transform to world coordinate system Transformation matrix Align the actual operating direction point of the oscillating saw with the coordinate system of the oscillating saw reference frame. Transform to world coordinate system : ； In the formula, and It is the coordinate system of the oscillating saw reference frame. The actual operating direction of the swing saw is correct. and World coordinate system The actual operating direction of the swing saw is correct; Then, based on the orientation alignment principle, determine the execution pose of the oscillating saw, and set the world coordinate system... The actual operating direction of the swing saw is correct. and , and the world coordinate system Target operation direction point pair and Alignment allows the oscillating saw to plan the osteotomy path based on CT images.

6. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 5, characterized in that, In step S5, the world coordinate system is... The actual operating direction of the swing saw is correct. and Through the world coordinate system To the femoral reference frame coordinate system Transformation matrix The femoral reference frame coordinate system is obtained by transformation. The actual operating direction of the swing saw is... and ; Then apply the transformation matrix Perform inverse transformation to obtain the femoral reference frame coordinate system To CT image coordinate system Transformation matrix By transforming the matrix femoral reference frame coordinate system The actual operating direction of the swing saw is... and Switch to CT image coordinate system The actual operation direction point is obtained below. and ; By calculating the osteotomy path point pairs based on CT images and With CT image coordinate system The actual operation direction point below and Positional error D and angular error between As error indicators, position error D and angle error Calculated using the following formula: ； ； In the formula, It is a CT image-based osteotomy path planning point pair and The direction vector formed CT image coordinate system The actual operation direction point below and The direction vector is formed; the position error is calculated. and angle error It can assess the accuracy of tool arrangement and provide error distribution data for subsequent optimization processes.

7. The method for optimizing the arrangement of orthopedic surgical tools based on noise error propagation according to claim 6, characterized in that, In step S6, in order to comprehensively evaluate error indices of different dimensions, the specific process of comparison and evaluation is as follows: Set the position error... Weighting coefficients and angle error Weighting coefficients Using formulas Calculate the comprehensive error evaluation value for each candidate surgical tool arrangement scheme. The comprehensive error evaluation value of all candidate surgical tool arrangement schemes is compared. Select the comprehensive error evaluation value The smallest possible arrangement is chosen as the final surgical tool arrangement.

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