CN114862780A

CN114862780A - Method and apparatus for determining femoral trochlear groove curve

Info

Publication number: CN114862780A
Application number: CN202210449759.2A
Authority: CN
Inventors: 林必贵; M·杰森; 王浩
Original assignee: Hangzhou Suwen Jiuzhou Medical Technology Co ltd
Current assignee: Hangzhou Suwen Jiuzhou Medical Technology Co ltd
Priority date: 2022-04-27
Filing date: 2022-04-27
Publication date: 2022-08-05
Also published as: WO2023206614A1

Abstract

A method and apparatus, storage medium, and electronic device for determining a trochlear groove curve of a femur that can be automatically identified based on a three-dimensional model of the femur reconstructed from CT pictures, comprising: generating a passing point P _LCP 、P _MCP And parallel to the plane U of the force line _PF (ii) a Generating the highest point P passing through the AP line direction on the medial epicondyle and the lateral epicondyle surfaces of the femur _LHP 、P _MHP And is perpendicular to the plane U _PF Plane U of _VH A curve L obtained by intersecting the distal surface of the femur _VH The minimum point of the middle y value is a point P _VHL (ii) a Generating a passing point P _FK Point P _VHL And is perpendicular to the plane U _PF Plane U of _HL Then, the curve L is obtained by intersecting with the distal surface of the femur _WS (ii) a By passing through the highest point P _LHP 、P _MHP In plane U _PF Projected point P of _LHP ' sum projection point P _MHP ' and curve L _WS Each plane U determined by any point _WSCi Extracting a profile curve L intersecting the distal surface of the femur _WSCi Then, the curve L is obtained _WSCi Each lowest point P distributed along the pulley groove _WSi (ii) a From the respective lowest points P _WSi Obtaining a fitting plane U by plane fitting _WS Intersecting the distal surface of the femur to obtain a sulcus curve L _WSF 。

Description

Method and apparatus for determining femoral trochlear groove curve

Technical Field

The invention relates to a method and a device for determining a femoral trochlear groove curve, a storage medium and an electronic device.

Background

Total Knee Arthroplasty (TKA) is a surgical procedure that replaces the surface of the knee. In TKA, the correctness of the femoral position is an important step in preoperative planning. Because of the correct placement of the femoral component, it is critical to ensure proper alignment of the patella on the femoral implant. To determine proper patellar rotational alignment, the trochlear groove curve (hereinafter also referred to simply as the groove curve) of the femoral trochlear groove deepest point must be determined.

This sulcus curve is very useful not only for rotational alignment of the patella, but also for determining the white plug line (whiteside). The white plug line is a line connecting the deepest point of the trochlear groove and the most anterior point of the femoral intercondylar notch when the femur is viewed from a plane perpendicular to the axial direction of the force line.

However, the accuracy of determining the trochlear groove curve remains one of the most challenging problems in TKA because satisfactory levels of accuracy and safety are often not achieved, and it requires a highly trained physician and is time consuming.

Disclosure of Invention

To solve the above problems, it is an object of the present invention to provide a method and apparatus, a storage medium, and an electronic device for determining a femoral trochlear groove curve, which can be used to assist surgical planning by automatically identifying the trochlear groove curve using a novel calculation method.

According to an aspect of the present invention, there is provided a method for determining a trochlear groove curve of a femur, which identifies and outputs a trochlear groove curve by virtually reconstructing a three-dimensional model of the femur based on acquired imaging data of the femur, comprising the steps of:

determining a force line of the femur and an AP line as a sagittal axis, and a point P for marking the center of the femoral knee, based on data of the three-dimensional model _FK Marking the point P of the lateral posterior condyle _LCP Mark point P of medial posterior condyle _MCP ；

Generating a passing point P _LCP 、P _MCP And is parallel to the force lineSecond plane U _PF ；

Determining the first highest point P in the direction of AP line on the medial epicondyle and the lateral epicondyle of the femur _LHP Second highest point P _MHP Generating a first peak P _LHP Second highest point P _MHP And is perpendicular to the second plane U _PF Third plane U of _VH Obtaining a third plane U _VH A first curve L obtained by intersecting the distal surface of the femur _VH Y value of (1) minimum point P _VHL The Y-axis corresponding to the Y-value is determined by projecting the AP line onto the third plane U _VH Is generated as above;

generating a passing point P _FK Point P _VHL And is perpendicular to the second plane U _PF Fourth plane U _HL Obtaining the fourth plane U _HL A second curve L obtained by intersecting the distal surface of the femur _WS ；

By passing through the first highest point P _LHP And a second highest point P _MHP In a second plane U _PF First projected point P of _LHP ' and second projection point P _MHP ', and a second curve L _WS Each plane U determined by any point _WSCi Extracting a profile curve L intersecting the distal surface of the femur _WSCi Then, the curve L is obtained _WSCi Each lowest point P distributed along the pulley groove _WSi Wherein i is 1, 2, 3 … n, n is a natural number;

from the respective lowest points P _WSi Obtaining a fifth fitting plane U by plane fitting _WS Obtaining the fifth fitting plane U _WS The curve obtained by intersecting the distal surface of the femur, i.e. the groove curve L of the trochlear groove _WS 。

Preferably, the method further comprises the following steps: determining a point P for marking the center of the hip joint based on data of the three-dimensional model _HP Through a point of attachment P _HP And point P _FK To obtain a straight line L as a force line _HF 。

Preferably, the method further comprises the following steps: generating a passing point P _FK And perpendicular to the first plane U of the force line _VF Then generates a passing point P _LCP Point P _MCP And is perpendicular to the first plane U _VF Second plane U of (A) _PF (ii) a Or generating a transit point P _LCP And point P _MCP And parallel to the second plane U of the force line _PF Then generates a passing point P _FK And perpendicular to the first plane U of the force line _VF 。

Preferably, the method further comprises the following steps: determining a point P for marking the lateral epicondyle based on the data of the three-dimensional model _LE Marking the point P of the medial epicondyle _ME Generating a straight line L as the AP line _AP The straight line L _AP Passing through point P _FK And perpendicular to the force line and to the point P _LE And point P _ME Projected to a first plane U _VF The resulting projection point P _LE ' sum projection point P _ME ' line L _LM ’。

Preferably, the method further comprises the following steps: by connecting the AP line L _AP And point P _FK Projected to a third plane U _VH Respectively as a third plane U _VH Finding a first curve L by using the Y axis and the origin O in the XOY coordinate system _VH Middle at the first highest point P _LHP And a second highest point P _MHP Y coordinate value minimum point P in between _VHL 。

Preferably, the method further comprises the following steps: by applying a second curve L _WS Dividing n segments equally to determine each plane U _WSCi 。

Preferably, the method further comprises the following steps: for each plane U _WSCi As AP line L _AP And point P _FK And respectively as the Y ' axis and the origin O ' of the coordinate system X ' O ' Y ' in this plane; for each plane U _WSCi Curve L in _WSCi Finding the maximum point P corresponding to the Y 'coordinate value Y' of the medial and lateral epicondyle portions _LHPi And a maximum point P _MHPi Determining the difference Deltay between the y 'values of the two maximum points, if Deltay'>e, wherein e is a preset value, curve L is obtained _WSCi Rotating around the origin O' of the coordinate system to form a point P _LHPi And point P _MHPi Keeping the value of y' equal, and obtaining a new curve L obtained at the moment _WSCi Value of 'y' minimum Point P _WSi As the lowest point of the update, a new curve L is found _WSCi 'maximum point P of y' value of the portion of the medial and lateral epicondyle corresponding superiorly _LHPi And a maximum point P _MHPi Determining the difference Deltay ' between the y ' values of the two maximum points, if Deltay '>e, repeating the rotation and judgment until delta y' is less than or equal to e.

Preferably, the method further comprises the following steps: for curve L _WSCi Fitting based on a 7 th order polynomial and a Van der Monte matrix is applied to obtain the curve L _WSCi Lowest point P of (2) _WSi 。

According to another aspect of the invention, there is provided an apparatus for assisting surgical planning by using trochlear groove curve data of a femur, comprising modules or units capable of carrying out the steps of any of the methods described above.

According to yet another aspect of the present invention, there is provided a computer readable storage medium storing a computer program for performing any of the methods described above.

According to still another aspect of the present invention, there is provided an electronic apparatus including: a processor and a memory for storing processor-executable instructions, the processor for reading the instructions from the memory and executing the instructions to implement any of the methods described above.

According to another aspect of the present invention, there is also provided an implant configured to have an artificial knee joint prosthesis manufactured using the femoral trochlear groove curve data determined by any one of the above-described methods as anatomical data of a patient.

According to another aspect of the present invention, there is also provided a method of identifying a white plug line, which is determined based on a femoral trochlear groove curve determined using any of the above methods.

The method and system according to the invention can extract the sulcus curve in the sagittal axis direction based on a geometric analysis of the intercondylar notch saddle, thereby allowing automatic identification of the sulcus curve along the trochlear groove. The trochlear groove can be used for rotational alignment of the femoral implant and the patella, can be used for determining a white plug line, and further can be used for auxiliary planning work such as determining an external rotation angle for placing the femoral prosthesis.

Drawings

FIGS. 1-3 are schematic diagrams of femoral marker points extracted for a method of determining a femoral trochlear groove curve according to an exemplary embodiment of the present invention;

4-12 schematically illustrate the identification process of a guideway curve;

FIG. 13 is a schematic flow diagram of a method for determining a femoral trochlear groove curve in accordance with an exemplary embodiment of the present invention;

fig. 14 is a structure of an electronic device provided according to an exemplary embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present invention are described in detail below with reference to the accompanying drawings. The exemplary embodiments described below and illustrated in the figures are intended to teach the principles of the present invention and enable one skilled in the art to implement and use the invention in several different environments and for several different applications. The scope of the invention is, therefore, indicated by the appended claims, and the exemplary embodiments are not intended to, and should not be considered as, limiting the scope of the invention. Also, terms such as "S1" to "S7", "step" and the like are intended to distinguish different objects rather than a specific order.

In TKA, the original articular surfaces of the knee joint are replaced with prosthetic components by cutting worn or damaged cartilage and bone at the distal femur and proximal tibia and then replacing the cut cartilage and bone with artificial implants. The implant is usually made of metal materials with good biocompatibility, such as titanium alloy or cobalt-chromium-molybdenum alloy, and high-molecular polyethylene materials to generate a new joint surface.

As a primary goal of preoperative planning, proper alignment of the patella on the femoral implant is ensured, thereby providing guidance for subsequent surgery. Therefore, the inventor finds a new fitting scheme for finding the trochlear groove curve of the femur through careful research.

The method according to an exemplary embodiment of the invention may be used to determine the position of the patella correctly fitting on the femoral implant before TKA, and may be applied in particular to preoperative planning and rotational alignment of the patella, thereby improving long term clinical outcomes and increasing the survival rate of the prosthesis.

< three-dimensional image reconstruction >

In the case of a TKA, for example, in which the distal portion of the femur, and at least a portion of the patella, is to be replaced, it is useful to have a 3D virtual display of the distal femur and patella.

To this end, in preoperative planning, imaging data of the patient's femur may be obtained by conventional interactive preoperative planning software using an imaging modality such as CT (Computed Tomography), a series of X-rays, ultrasound, or Magnetic Resonance Imaging (MRI) to generate a 3D image model of the bone after transmission of the digitized images to a computer system. In particular embodiments, a patient's bone may be segmented manually, semi-manually, or automatically by a user to generate a 3D model of the bone.

For example, CT images are often used as a reference for surgical planning. The CT image can be moved into a virtual space, and the bones in the CT image can be superposed with the structures of the real bones through the extraction of the same characteristic points, so that the whole structures of the bones in the CT image are moved into the virtual space to replace the pose of the real bone structures in the virtual space. The main purposes of this process are: 1, displaying the integral structure of the bone in a virtual coordinate system; assisting the physician in surgical planning allows the physician to place the implant into a 3D model of the bone anatomy to specify the optimal location and alignment of the implant on the bone. The surgical robot can be further assisted to perform accurate fitting between the femoral component of the knee joint prosthesis and the femur, i.e. simulated assembly of the prosthesis.

The resulting preoperative planning data may also be used to manufacture patient-specific instruments or be loaded and read by surgical equipment to assist the physician in intraoperatively performing the planning and even positioning the surgical robot to ensure the space of the robot into the desired surgical field.

The method and apparatus for reconstructing three-dimensional images and establishing a femoral coordinate system are not essential to the present invention, and are not described herein again, and can be implemented by using the above-mentioned existing means.

The method according to the invention for determining the curve of the femoral trochlear groove is described below starting from the reconstruction of a three-dimensional image, taking a CT scan as an example.

For example, as image data, the sequence of dicom files of a CT scan is reorganized and repartitionable, thereby combining the sequence of CT files into one complete three-dimensional image.

< Curve identification Process >

Fig. 13 is a flow chart illustrating a method for determining a femoral trochlear groove curve according to an exemplary embodiment of the present invention. The present embodiment can be applied to an electronic device, and as shown in fig. 13, the groove profile identification process includes the following steps:

step S1: determining a femoral marker point based on the acquired three-dimensional model including the distal femur, comprising: marking the point P of the center of the femoral knee _FK Marking the point P of the lateral epicondyle _LE Marking the point P of the medial epicondyle _ME Marking the point P of the lateral posterior condyle _LCP Marking the point P of the medial posterior condyle _MCP ；

Step S2: determining a passing point P _FK Generating a passing point P _FK And perpendicular to the plane U of the force line _VF And a passing point P _LCP Point P _MCP And is perpendicular to the plane U _VF Plane U of _PF ；

Step S3: generating a line L corresponding to the sagittal axis AP line _AP The straight line L _AP Passing through point P _FK And perpendicular to the force line and to the point P _LE And point P _ME Projected to plane U _VF The resulting projection point P _LE ' and P _ME ' line L _LM ’；

Step S4: determining the highest point P on the medial and lateral epicondyle surfaces of the femur in the direction of the AP line _LHP Highest point P _MHP Generating a passing peak P _LHP Highest point P _MHP And is perpendicular to the plane U _PF Plane U of _VH Obtaining a plane U _VH Curve L obtained by intersecting the distal surface of femur _VH Y value of (1) minimum point P _VHL The Y axis corresponding to the Y value passes through the AP line L _AP Projected to plane U _VH Is generated as above;

step S5: generating a passing point P _FK 、P _VHL And is perpendicular to the plane U _PF Fourth plane U _HL Obtaining the fourthPlane U _HL Curve L obtained by intersecting the distal surface of femur _WS ；

Step S6: by passing through the highest point P _LHP And the highest point P _MHP In plane U _PF Projected point P of _LHP ' sum projection point P _MHP ', and curve L _WS Each plane U determined by any point _WSCi Extracting a profile curve L intersecting the distal surface of the femur _WSCi Then, the curve L is obtained _WSCi Each lowest point P distributed along the pulley groove _WSi (i ═ 1, 2, 3 … n, n is a natural number);

step S7: from the respective lowest points P _WSi Obtaining a fifth fitting plane U by plane fitting _WS Using a fifth fitting plane U _WS The curve obtained by intersecting the distal surface of the femur, i.e. the groove curve L of the trochlear groove _WSF 。

Regarding step S1, to find the sulcus curve of the trochlear groove, it is necessary to first find the three-dimensional model of the distal end of the femur and its corresponding marker points.

In particular, the following femoral marker points may be extracted from the three-dimensional model based on CT images:

hip joint center (HP, hip joint center): point P _HP ；

Femoral knee center (FK, femur knee center): point P _FK ；

-Lateral Epicondyle (LE): point P _LE ；

Medial Epicondyle (ME): point P _ME ；

Lateral posterior condyles (LCP): point P _LCP ；

-Medial Condyle (MCP): point P _MCP 。

Thus, the point P can be found on the proximal and distal surfaces of the three-dimensional model of the femur _HP 、P _FK 、P _LE 、P _ME 、P _LCP 、P _MCP 。

Specifically, as shown in fig. 1 to 3, in a coordinate system xyz for indicating the pose of the three-dimensional model of the femur, the x direction is the coronal axis direction of the coronal plane, the y direction is the sagittal axis direction of the sagittal plane, and the z direction is the vertical axis direction perpendicular to the transverse plane.

Regarding step S2, as shown in FIG. 4, the connection point P may be passed _HP And point P _FK To obtain a straight line L as a force line _HF (ii) a Passing point P _FK Perpendicular to the straight line L _HF Plane U of _VF (ii) a Passing point P _LCP And point P _MCP Generating a perpendicular to plane U _VF Plane U of _PF 。

With respect to step S2, the force lines may also be determined by other known means based on data of the three-dimensional model of the femur. For example, a 3D model in stl (streohithography) format automatically generated by CT scanning is decomposed into a point cloud image, point cloud data is fitted, and a straight line connecting two distal and proximal ends of a femur obtained is determined as a force line. For example, stacking all CT scan results in the z-axis (i.e., stacking two-dimensional images parallel to the cross-sectional plane, x-axis long and y-axis wide, along the z-axis, while presenting a 3D image that is high along the z-axis) yields a 3D model in STL format. Accordingly, the model can be decomposed into a point cloud image, and the x-axis and y-axis coordinates of each point therein can be easily known. Certainly, the force line can also be determined by adopting a neural network for segmentation, a numerical algorithm and the like, and other key points can also be calculated from the point cloud data, which is not described herein again.

Regarding step S2, the passing point P may also be generated first _LCP And point P _MCP And parallel to the plane U of the force line _PF Then generates a passing point P _FK And perpendicular to the plane U of the force line _VF 。

With respect to step S3, as shown in FIG. 5, point P may be identified _LE And P _ME Projected to plane U _VF To obtain a projection point P _LE ’，P _ME ' and line L connecting thereto _LM '; passing point P _FK Perpendicular to the straight line L _HF And a straight line L _LM ' line L _AP I.e. the sagittal axis AP line (anti spatial porerior line).

With respect to step S4, as shown in FIG. 6, the highest point P in the direction of AP line is found on the medial and lateral epicondyle surfaces of the femur _LHP And the highest point P _MHP Go through two points to make perpendicularityIn the plane U _PF Plane U of _VH (ii) a Using plane U _VH Cutting and intersecting the distal surface of the femur to obtain a section containing the highest point P _LHP And the highest point P _MHP Curve L of _VH (ii) a Will AP line L _AP And point P _FK Projected to plane U _VH Up, respectively as plane U _VH Finding the curve L by the Y axis and the origin O under the XOY coordinate system _VH Y coordinate value of (3) minimum point P _VHL 。

Herein, the maximum points refer to points on the surface profile of the medial and lateral femoral condyles which are farthest from the coronal plane along the direction of the AP line, and the maximum points are not limited to the same Y-coordinate values in the direction of the AP line, and may correspond to two different height values, respectively.

Here, curve L _VH Y coordinate value of (3) minimum point P _VHL Preferably at the highest point P _LHP And the highest point P _MHP The point in between.

Regarding step S4, the AP line may also be determined by other known means based on the data of the three-dimensional model of the femur, which will not be described herein.

Regarding step S5, as shown in FIG. 6, the passing point P _FK And point P _VHL Making U perpendicular to plane _PF Plane U of _HL (ii) a Using plane U _HL Cutting and intersecting the distal surface of the femur to obtain a curve L _WS 。

Here, curve L _WS The ends terminate at the boundary of the distal surface of the femur to form the following compartments for segmentation.

Regarding step S6, as shown in FIG. 7, the curve L may be _WS Dividing the obtained point P into 20 segments (other values such as 10, 30, without limitation) to obtain a plurality of points P _WSi (i is a natural number such as 1, 2, 3 … 20, etc.);

point P _LHP And point P _MHP Projected to plane U _PF To correspondingly obtain a projection point P _LHP ' and Point P _MHP ’；

Since three points can define a plane, the point P is crossed _LHP ', point P _MHP ' and Point P _WSi Can generate a plurality of planes U _WSCi (subscript C herein means a cross-section), and in turn with plane U _WSCi Cutting and crossing the distal surface of femur to obtain several curves L _WSCi Accordingly, plane U is shown in FIG. 8 _WSCi The profile of the cross-section of the distal surface of the femur, a partially contoured curve L is shown in FIG. 9 _WSCi ；

For each plane U _WSCi As AP line L _AP And point P _FK And respectively taking the projection as a Y ' axis and an origin O ' in the plane, and establishing a coordinate system X ' O ' Y ' on the plane;

for each plane U _WSCi Curve L in _WSCi Finding out the maximum point P of the Y 'coordinate value Y' of the portion of the current curve corresponding to medial and lateral epicondyles according to the in-plane coordinate system X 'O' Y _LHPi And P _MHPi Determining the difference Δ y between the two y 'values, if Δ y'>e (set threshold), curve L _WSCi Rotating around the origin O' of the coordinate system to rotate P _LHPi And P _MHPi The two points are kept horizontal (the y' value is equivalent), and a new curve L is obtained at the moment _WSCi 'y' value minimum point (nadir) P _WSi . For new curve L _WSCi 'analysis is performed to find the maximum point P of the y' value of the portion of the curve corresponding to the medial and lateral epicondyle _LHPi And P _MHPi Determining the difference Δ y ' between the values of y ' and Δ y '>e (setting threshold), repeating the above steps, and if delta y'<e, the next step is carried out.

Thus, through step S6, the lowest points P of the distal surface of the femur along the trochlear groove can be obtained _WSi . Therein, fig. 10 shows an updated curve L resulting from the rotational profile _WSCi ' and updated lowest Point P _WSi 。

Regarding step S7, for several lowest points P distributed along the pulley groove _WSi Fitting the plane with the fitting plane as U _WS Using plane U _WS Intersecting with the distal surface of femur to obtain groove curve L of the pulley groove _WSF (F here refers to the final curve), as shown in FIG. 11.

Further, in the above-described step S6, with respect to each plane U _WSCi As the outer shape ofCurve L of a partial curve of a contour _WSCi For optimization, the curve also includes the highest point P of the medial and lateral condyles _LHP And P _MHP The convergence difficulty and the calculation complexity caused by the method are used for better obtaining the profile curve L _WSCi Lowest point P of _WSi The fitting may preferably be performed using a higher order polynomial alignment, and the fitted profile may be approximated as a fitted curve equation as follows:

y＝a _n x ⁿ +a _n-1 x ^n-1 +…+a ₁ x+a ₀ … … (formula 1) in the form of a powder,

wherein n is a natural number, a ₀ ，a ₁ ，……a _n The coefficients of each variable or the coefficient of the high power of each variable in the fitting curve formula are specific numerical values instead of variables after each fitting curve is determined.

In the experiments carried out, a 7 th degree polynomial was found to be sufficient to model curve L well _WSCi 。

The fitting process of the polynomial uses a vandermonde matrix. This matrix is obtained from a generic matrix representing the evaluation of a 7 th order polynomial model at each point of the profile, as shown below.

Each point P, slave P ₁ To P _k The following holds true:

wherein, the original contour is a discrete value, P is a discrete point on the contour curve after cutting, and k is the number of the points.

Multiplying both sides by the transpose of the first matrix yields the vandermonde matrix, the solution of the system giving the coefficients of the polynomial sought.

In addition, in step S6, the curve L may be set to _WSCi The rotation is carried out around the origin of the coordinate system, and the space triangle rotation method and the plane triangle rotation method can also be combined.

In addition, XOY and X ' O ' Y ' in the above steps are used to indicate the in-plane coordinate system in the current step, which may be different from each other due to re-establishment.

Exemplary devices

There is also provided in accordance with an exemplary embodiment of the invention, an apparatus useful for determining a femoral trochlear groove curve, including a corresponding module or unit capable of carrying out the steps of the method described above.

Exemplary electronic device

Fig. 14 is a structure of an electronic device according to an exemplary embodiment of the present invention. The electronic device may be either or both of the first device and the second device, or a stand-alone device separate from them, which stand-alone device may communicate with the first device and the second device to receive the acquired input signals therefrom. FIG. 14 illustrates a block diagram of an electronic device in accordance with an embodiment of the disclosure. As shown in fig. 14, the electronic device includes one or more processors 51 and a memory 52.

The processor 51 may be a Central Processing Unit (CPU) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

The memory 52 may include one or more computer program products that may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, Random Access Memory (RAM), cache memory (cache), and/or the like. The non-volatile memory may include, for example, Read Only Memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium and executed by the processor 51 to implement the page processing methods of the various embodiments of the present disclosure described above and/or other desired functions. In one example, the electronic device may further include: an input device 53 and an output device 54, which are interconnected by a bus system and/or other form of connection mechanism (not shown).

The input device 53 may also include, for example, a keyboard, a mouse, and the like.

The output device 54 is used for outputting various information to the outside, and may include, for example, a display, a speaker, a printer, and a communication network and a remote output device connected thereto.

Of course, for simplicity, only some of the components of the electronic device relevant to the present disclosure are shown in fig. 14, omitting components such as buses, input/output interfaces, and the like. In addition, the electronic device may include any other suitable components, depending on the particular application.

Exemplary computer program product and computer-readable storage Medium

In addition to the methods and apparatus described above, embodiments of the present disclosure may also be a computer program product comprising computer program instructions that, when executed by a processor, cause the processor to perform the steps in a method for determining a femoral trochlear groove curve according to various embodiments of the present disclosure described in the "exemplary methods" section above in this specification.

The computer program product may write program code for carrying out operations for embodiments of the present disclosure in any combination of one or more programming languages, including an object oriented programming language such as Java, C + + or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server.

Furthermore, embodiments of the present disclosure may also be a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, cause the processor to perform the steps in a method for determining a femoral trochlear groove curve according to various embodiments of the present disclosure described in the "exemplary methods" section above in this specification.

The computer-readable storage medium may take any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may include, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The foregoing describes the general principles of the present disclosure in conjunction with specific embodiments, however, it is noted that the advantages, effects, etc. mentioned in the present disclosure are merely examples and are not limiting, and they should not be considered essential to the various embodiments of the present disclosure. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the disclosure is not intended to be limited to the specific details so described.

In the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts in the embodiments are referred to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The block diagrams of devices, apparatuses, systems referred to in this disclosure are only given as illustrative examples and are not intended to require or imply that the connections, arrangements, configurations, etc. must be made in the manner shown in the block diagrams. These devices, apparatuses, devices, systems may be connected, arranged, configured in any manner, as will be appreciated by those skilled in the art. Words such as "including," "comprising," "having," and the like are open-ended words that mean "including, but not limited to," and are used interchangeably therewith. The words "or" and "as used herein mean, and are used interchangeably with, the word" and/or, "unless the context clearly dictates otherwise. The word "such as" is used herein to mean, and is used interchangeably with, the phrase "such as but not limited to".

The methods and apparatus of the present disclosure may be implemented in a number of ways. For example, the methods and apparatus of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above-described order for the steps of the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above unless specifically stated otherwise. Further, in some embodiments, the present disclosure may also be embodied as programs recorded in a recording medium, the programs including machine-readable instructions for implementing the methods according to the present disclosure. Thus, the present disclosure also covers a recording medium storing a program for executing the method according to the present disclosure.

It is also noted that in the devices, apparatuses, and methods of the present disclosure, each component or step can be decomposed and/or recombined. These decompositions and/or recombinations are to be considered equivalents of the present disclosure. The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the disclosure. Thus, the present disclosure is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

< related Art effects >

According to the present invention, a trochlear groove curve can be automatically output for easy use by a computer-assisted surgery system, thereby achieving reliable implant alignment and post-operative clinical results.

Firstly, CT scanning and the like can be carried out on thighbone, and a three-dimensional model is established; establishing a virtual imaging space in three-dimensional modeling software by using the obtained space position parameters; selecting each characteristic point specified by the conditions in the three-dimensional model to obtain corresponding position information; various planes for planning TKA, including coronal, sagittal, and axial planes, may also be obtained, and the force line, AP line, may be determined accordingly.

Thus, in the surgical planning phase, predetermined parameters, in particular more accurate data about the trochlear groove curve, can be provided for a computer aided navigation system or a robotic surgery system, better simulation and planning operations can be obtained in the system based on information provided by CT scanning and the like in combination with the implant, a basis for aligning and positioning the implant component to the femoral model in a clinically established standard reference frame can be provided, and the implant can be automatically aligned with the patella. The physician need only import the implant model to the computer system preoperatively and provide data on the position and orientation of the implant, thereby significantly reducing the time spent in creating the preoperative plan and intraoperative osteotomy positioning.

Furthermore, the implants described herein, as a whole or part that can be used to replace bone, correspond to implants or prostheses commonly referred to in orthopaedics, i.e. can be understood to include prostheses for knee replacement. The prosthesis may be used to internally secure fractured or damaged portions of a fracture.

While the invention has been described with reference to various specific embodiments, it should be understood that changes can be made within the spirit and scope of the inventive concepts described. Accordingly, it is intended that the invention not be limited to the described embodiments, but that it will have the full scope defined by the language of the following claims. It is obvious to those skilled in the art that technical solutions that can be easily conceived based on the disclosure of the present invention should also be considered to be equivalent or equivalent and fall within the scope of the present invention.

Claims

1. A method for determining a trochlear groove curve of a femur by virtually reconstructing a three-dimensional model of the femur based on acquired imaging data of the femur, comprising the steps of:

based on the threeData of a dimensional model, determining a force line of the femur and an AP line as sagittal axis, and a point P for marking the center of the femoral knee _FK Marking the point P of the lateral posterior condyle _LCP Marking the point P of the medial posterior condyle _MCP ；

Generating a passing point P _LCP 、P _MCP And parallel to the second plane U of the force line _PF ；

Determining the first highest point P in the direction of AP line on the medial epicondyle and the lateral epicondyle of the femur _LHP Second highest point P _MHP Generating a first peak P passing through _LHP The second highest point P _MHP And is perpendicular to the second plane U _PF Third plane U of _VH Obtaining the third plane U _VH A first curve L obtained by intersecting the distal surface of the femur _VH Y value minimum point P in (1) _VHL The Y-axis corresponding to the Y-value is determined by projecting the AP line onto the third plane U _VH Is generated as above;

By passing through said first highest point P _LHP And said second highest point P _MHP In the second plane U _PF First projected point P of _LHP ' and second projection point P _MHP ', and the second curve L _WS Each plane U determined by any point _WSCi Extracting a cross-sectional profile L of the distal surface of the femur _WSCi Then, the curve L is obtained _WSCi Each lowest point P distributed along the pulley groove _WSi Wherein i is 1, 2, 3 … n, n is a natural number;

from the respective lowest points P _WSi Obtaining a fifth fitting plane U by plane fitting _WS Obtaining the fifth fitting plane U _WS The curve obtained by intersecting the distal surface of the femur, i.e. the groove curve L of the trochlear groove _WSF 。

2. The method for determining a femoral trochlear groove curve as in claim 1, further comprising:

determining a point P for marking the center of the hip joint based on the data of the three-dimensional model _HP Through a point of attachment P _HP And point P _FK Obtaining a straight line L as said force line _HF 。

3. The method for determining a femoral trochlear groove curve as in claim 1 or above, further comprising:

generating a passing point P _FK And perpendicular to the first plane U of the force line _VF Then generates a passing point P _LCP Point P _MCP And is perpendicular to the first plane U _VF Second plane U _PF (ii) a Or

Generating a passing point P _LCP And point P _MCP And parallel to a second plane U of the line of force _PF Then generates a passing point P _FK And perpendicular to the first plane U of the force line _VF 。

4. The method for determining a femoral trochlear groove curve as in claim 3, further comprising:

determining a point P for marking the lateral epicondyle based on the data of the three-dimensional model _LE Marking the point P of the medial epicondyle _ME ，

Generating a straight line L as the AP line _AP The straight line L _AP Passing through point P _FK And perpendicular to said line of force and to point P _LE And point P _ME Projected to the first plane U _VF The resulting projection point P _LE ' sum projection point P _ME ' line L _LM ’。

5. The method for determining a femoral trochlear groove curve as in claim 4, further comprising:

by combining the straight line L _AP And point P _FK Projected to the third plane U _VH Respectively as the third plane U _VH Finding the first curve L by using the Y axis and the origin O in the XOY coordinate system _VH Is located at the first highest point P _LHP And said second highest point P _MHP Y coordinate value minimum point P in between _VHL 。

6. The method for determining a femoral trochlear groove curve as in claim 1, further comprising:

by applying said second curve L _WS Equally dividing n segments to determine said respective planes U _WSCi 。

7. The method for determining a femoral trochlear groove curve of claim 1 or 6, further comprising:

for each plane U _WSCi Make AP line and point P _FK And respectively as the Y ' axis and the origin O ' of the coordinate system X ' O ' Y ' in this plane;

for each plane U _WSCi Curve L in _WSCi Finding the maximum point P corresponding to the Y 'coordinate value Y' of the medial and lateral epicondyle portions _LHPi And a maximum point P _MHPi Determining the difference Deltay between the y 'values of the two maximum points, if Deltay'>e, wherein e is a preset value, curve L is obtained _WSCi Rotating around the origin O' of the coordinate system to form a point P _LHPi And point P _MHPi Keeping the value of y' equal, and obtaining a new curve L obtained at the moment _WSCi Value of 'y' minimum Point P _WSi As the lowest point of the update, a new curve L is found _WSCi 'maximum point P of y' value of the portion of the medial and lateral epicondyle corresponding superiorly _LHPi And a maximum point P _MHPi Determining the difference Deltay ' between the y ' values of the two maximum points, if Deltay '>e, repeating the rotation and judgment until delta y' is less than or equal to e.

8. The method for determining a femoral trochlear groove curve as set forth in claim 1, further comprising:

for the curve L _WSCi Fitting based on a 7 th order polynomial and a Van der Monte matrix is applied to obtain the curve L _WSCi Lowest point P of _WSi 。

9. An apparatus for assisting surgical planning by using trochlear groove curve data of a femur,

a module or unit comprising means capable of carrying out the steps of the method of any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program for performing the method of any one of claims 1-8.

11. An electronic device, comprising: a processor and a memory for storing instructions executable by the processor, the processor being configured to read the instructions from the memory and execute the instructions to implement the method of any of claims 1 to 8.

12. An implant, characterized in that,

an artificial knee joint prosthesis configured to be manufactured by using the femoral trochlear groove curve data determined by the method according to any one of claims 1 to 8 as anatomical data of a patient.

13. A method for identifying a white plug line is characterized in that,

determining the white plug line based on a femoral trochlear groove curve determined using the method of any one of claims 1-8.