A system and method for generating a structural model of the acetabular lunate surface

Abstract

The present invention relates to a system and method for generating an acetabular lunate surface structure model, including an acetabular lunate surface measurement module, which extracts an os coxae image based on a three-dimensional stereoscopic image and traverses at least one vertex of the os coxae image. When the line segments formed by the vertices along the normal direction intersect with the original femoral head necrosis model or the original femoral head model respectively, the vertex is defined as an acetabular point and extracted. When the acetabular points are repeatedly extracted and an acetabular point set is formed, the acetabular lunate surface measurement module generates a triangular patch set composed of at least three vertices that are subsets of the acetabular point set by traversing at least one triangular patch of the os coxae image, and generates an acetabular lunate surface model by removing isolated noise points based on the triangular patch set. The method for generating the acetabular lunate surface model in the present invention avoids complex model operations and does not require other data sets for training to obtain prior knowledge, and has the advantages of simple implementation and high model accuracy.

Description

[0001] Division Explanation

[0002] The original basis of this divisional application is a patent application with the application number 201910878908.5, the application date of September 17, 2019, and the invention title of "An Analysis Device and Method for the Integrity Rate of Femoral Head". Technical Field

[0003] The present invention relates to the technical field of femoral head detection, and particularly to a system and method for generating an acetabular lunate surface structure model. Background Art

[0004] Femoral head necrosis is a relatively common joint disease. The factors causing femoral head necrosis are various, such as fractures, alcoholism, extensive use of hormones, blood diseases, burns, etc. At the onset of the disease, the blood supply to the tissues adjacent to the joint surface of the patient will be damaged, which will then cause ischemia of the entire femoral head. The femoral head of the patient will deform and collapse, and the joint function will also be severely damaged. It is difficult to diagnose this disease simply based on clinical symptoms and signs, and misdiagnosis or missed diagnosis is likely to occur. At present, the main detection methods clinically are three diagnostic methods: X-ray examination, CT examination, and magnetic resonance examination.

[0005] Bone marrow cell damage is a most critical clinical manifestation of femoral head necrosis. The most essential factor causing this damage is that the femoral head cannot obtain timely and sufficient blood supply. Medical experts have staged the clinical observation of the femoral head. Stage I is the ischemic cell death stage. The death of osteoblasts and bone mother cells in the femoral head occurs after 5 days, showing a batch form of death. Stage II is the femoral cell repair and decomposition stage, and the decomposition of necrotic tissues is the main manifestation of this stage. During the repair process, inflammatory reactions will occur between the active and healthy tissues and the diseased tissues, leading to abnormal metabolism of bone collagen fibers in the femoral head and further occlusion of microvessels. Stage III belongs to the repair stage, and necrosis absorption and hyperplasia may coexist when connective tissues and blood vessels are repaired. In stage IV, the femoral head will collapse. During the femoral head collapse stage, cartilage degeneration and defect will occur, which will then lead to the occurrence of arthritis lesions. In the clinical diagnosis of femoral head necrosis, X-ray examination is the most widely used method. Through the examination, the progress of the patient's condition and the degree of bone necrosis can be mainly understood. CT examination is also mainly used to understand the condition of the patient's bone necrosis, and appropriate treatment methods can be selected by analyzing the images.

[0006] The treatment methods for femoral head necrosis are divided into surgical treatment and non-surgical treatment.

[0007] The non-surgical treatment usually has the following methods:

[0008] 1. Avoid weight-bearing: This includes partial weight-bearing and non-weight-bearing, and is only applicable to osteonecrosis of the femoral head before collapse, that is, Ficat stage I and II. Judging from the literature reports, the effect of simply adopting the treatment method of avoiding weight-bearing is not ideal, and the success rate is less than 15%. For osteonecrosis of the femoral head with lesions located in the medial part of the femoral head, this method can be considered.

[0009] 2. Drug treatment: There are few reports on the use of drugs to treat osteonecrosis of the femoral head. Generally speaking, the effect of drug treatment is still uncertain, but due to its non-invasive nature, it remains an important research direction.

[0010] 3. Other treatment methods: Such as electrical stimulation therapy, shock wave therapy, hyperbaric oxygen therapy, etc. There are not many reports, and the effects need to be further determined.

[0011] Surgical treatment usually has the following methods:

[0012] 1. Surgery for preserving the femoral head. (1) Core decompression: The theoretical basis for core decompression in the treatment of avascular necrosis of the femoral head is the theory of increased intraosseous pressure in osteonecrosis. By core decompression, the intraosseous pressure can be reduced, blood flow in the femoral head can be increased, and core decompression can stimulate the growth of blood vessels in the decompression tunnel, promoting the creeping substitution of necrotic bone. There are many articles on core decompression, and there is a great deal of controversy about its efficacy. Its efficacy is closely related to the stage of femoral head necrosis, and has little to do with the etiology of femoral head necrosis. (2) Classical osteotomy: The purpose of osteotomy is to change the main weight-bearing area of the femoral head, replacing necrotic bone with normal bone as the main weight-bearing area. This method includes trochanteric rotational osteotomy, intertrochanteric varus osteotomy, and intertrochanteric valgus osteotomy, etc., and can also be combined with bone grafting. It is mainly applicable to patients in Ficat stage II and III with a small lesion area. The osteotomy position of classical osteotomy is in the intertrochanteric region. The biggest disadvantage is that if the patient needs to undergo hip replacement again, the surgical difficulty is increased. (3) Bone grafting: Bone grafting includes autologous cancellous bone grafting, autologous cortical bone grafting, allogeneic bone grafting, and cartilage grafting, and can be combined with other treatment methods such as core decompression, electrical stimulation, and osteotomy. Bone grafting methods include grafting after core decompression, slotting and grafting at the junction of the head and neck, fenestrating the articular cartilage of the femoral head, lifting the cartilage for grafting and then reducing the cartilage, etc. Bone grafting can be used for patients in Ficat stage II, early stage III, and patients who have failed core decompression. The short-term efficacy of this method is relatively certain, and there is still controversy about the long-term efficacy. However, it is worthy of affirmation to accelerate the repair of the femoral head and shorten the bedridden time by bone grafting. Combining methods to promote bone healing such as growth factors and electrical stimulation can improve its efficacy. (4) Vascularized bone grafting: There are many methods of vascularized bone grafting. The grafted bone can come from the ilium, greater trochanter, or fibula, and can be with a muscle pedicle or a vascular pedicle. Compared with ordinary bone grafting, vascularized bone grafting can increase the blood supply of the femoral head and accelerate bone healing. Literature reports that its clinical effect is relatively ideal, but the improvement of X-ray is not ideal, and a considerable number of patients still need hip replacement during long-term follow-up. (5) Trabecular metal AVN reconstruction rod (tantalum rod): The trabecular metal AVN reconstruction rod is a porous tantalum metal prosthesis with a porosity, three-dimensional structure, and elastic modulus similar to cancellous bone. Its high friction coefficient with bone helps to maintain the initial stability after implantation. After implantation, it can form a structural support for the necrotic area, facilitate the revascularization of the bone necrosis area, and can be implanted by a minimally invasive method. These characteristics are all conducive to preventing the collapse and repair of the femoral head necrosis area, and delaying the age of hip replacement. (6) Modified osteotomy: The same as classical osteotomy, its purpose is to change the main weight-bearing area of the femoral head, replacing necrotic bone with normal bone as the main weight-bearing area. It is mainly applicable to patients in Ficat stage II and III with a small lesion area. The difference between this surgical method and classical osteotomy is that the osteotomy position is at the base of the femoral neck, and it will not increase the surgical difficulty during hip replacement for patients.

[0013] 2. Joint replacement surgery. (1) Hip resurfacing arthroplasty: Hip resurfacing arthroplasty replaces the joint surface with an implant, preserves most of the subchondral bone of the acetabulum and femoral head, does not invade the femoral neck and femoral medullary cavity, and while treating the disease, preserves the normal physiological anatomical structure and relationship as much as possible. (2) Total hip arthroplasty: It is the only option for the treatment of advanced femoral head necrosis. With the progress of research on friction interfaces and the application of new materials (such as ceramic artificial joints), the population of suitable candidates for total hip arthroplasty has a trend of getting younger.

[0014] However, at present, the diagnosis of femoral head necrosis at home and abroad mainly comes from CT / MR imaging examinations, which are difficult to accurately judge the three-dimensional spatial relationship of femoral head necrosis, cannot calculate the necrosis rate of the femoral head weight-bearing area to the maximum extent in three-dimensional space, cannot meet the surgical simulation training of orthopedic doctors for femoral head necrosis, and cannot fully meet the clinical needs of femoral head necrosis surgical treatment. Orthopedic doctors can only estimate the rotation angle based on CT / MR images and roughly estimate whether it is possible to move most of the necrotic bone area out of the weight-bearing area and move the normal bone area into the weight-bearing area after rotating the corresponding angle. Moreover, even if the estimated result is obtained, in actual surgery, some doctors may still need to rotate to different angles to try whether there may be a better surgical plan. This not only poses a great test to the various abilities of doctors, but also the surgical plan obtained may have certain defects.

[0015] Among them, for osteotomy, its main purpose is to rotate the truly normal bone on the femoral head to the weight-bearing area and move the necrotic area on the femoral head out of the weight-bearing area to avoid femoral head collapse and relieve the patient's pain. Usually before surgery, surgeons need to obtain as accurate anatomical images (bones, blood vessels, muscles, etc.) of the surgical object's body structure as possible in order to carry out surgical planning, such as determining the size and position of the incision, how to avoid adjacent important organs, the best osteotomy position, osteotomy amount, displacement and rotation amount, in order to obtain a perfect and successful surgical effect. Therefore, solving how to accurately judge the three-dimensional spatial relationship of femoral head necrosis and calculating the necrosis rate of the femoral head weight-bearing area to the maximum extent in three-dimensional space is an urgent problem in the medical field of treating femoral head necrosis.

[0016] Chinese Patent (Publication No. CN108921832A) discloses a method, apparatus, server, and medium for femoral head image analysis. The method includes: creating a three-dimensional model of the femoral head based on a target image of the femoral head including a necrotic area, where the three-dimensional model includes a three-dimensional model of the proximal femur and a three-dimensional model of necrotic bone; creating an analysis model of the femoral head based on the three-dimensional model; and extracting the equivalent stress and total deformation of the weight-bearing area of the femoral head based on the analysis model and performing data analysis. The embodiments of this patent solve the problem of low accuracy of femoral head image analysis results in the prior art and improve the accuracy of femoral head image analysis results.

[0017] Chinese Patent (Publication No. CN108711187A) discloses a method for registering and fusing CT and MRI signals to establish a three-dimensional simulation model of the human lumbar spine, including: collecting computer tomography (CT) images; collecting magnetic resonance imaging (MRI) images; establishing a three-dimensional model of the CT images; establishing a three-dimensional model of the MRI images; registering and fusing the three-dimensional model of the CT images and the three-dimensional model of the MRI images, including simple registration according to the lumbar spine anatomical structure and global calculation registration. This patent makes full use of existing conventional examinations such as CT and MRI in combination with an optimized MRI scanning sequence to establish important soft tissue three-dimensional models of the lumbar intervertebral disc, nerve root, and ligamentum flavum that can mutually verify the accuracy within each MRI sequence, establishing a new high-accuracy modeling method for lumbar intervertebral discs in medical imaging, and at the same time greatly improving the utilization rate of medical imaging examination data.

[0018] Chinese Patent (Publication No. CN107296650A) discloses an intelligent surgical assistance system based on virtual reality and augmented reality. It includes a data preprocessing unit, a preoperative planning unit, and an intraoperative assistance unit. The data preprocessing unit reconstructs a three-dimensional lesion model using the original CT / MRI images; the preoperative planning unit builds a virtual imaging studio through virtual reality devices, loads the three-dimensional lesion model, and allows users to make surgical plan planning by delving into the interior of the diseased organ and exports the three-dimensional planning model; the intraoperative assistance unit calls the three-dimensional planning model through augmented reality devices, obtains its spatial feature points and registers and fuses them with the real lesion site to help doctors identify anatomical structures, and at the same time displays surgical plan decisions and quantitative physiological data to execute the preoperative planning. This patent solves the problems of difficult identification of anatomical structures and lack of real-time navigation during surgery and improves the success rate of surgical operations.

[0019] However, none of the above patents can effectively calibrate the detection results of the necrotic weight-bearing area and the femoral weight-bearing area, and cannot accurately calculate the integrity rate of the lateral femoral weight-bearing area. For example, it is difficult to accurately judge the spatial three-dimensional relationship of femoral head necrosis, unable to calculate the necrosis rate of the femoral head weight-bearing area to the maximum extent in three-dimensional space, unable to meet the needs of orthopedic surgeons for surgical simulation training of femoral head necrosis, and cannot fully meet the clinical needs of femoral head necrosis surgical treatment. Therefore, in order to overcome the deficiencies of the prior art and solve at least one of the above technical problems, the present invention provides an analysis device and method for the integrity rate of the femoral head that can comprehensively analyze and judge based on the original femoral head necrosis model, original femoral head model, and acetabular lunate surface model of three-dimensional stereoscopic images.

[0020] The patent document with the publication number CN108921832A discloses a femoral head image analysis method, device, server, and medium. Among them, the method includes: creating a three-dimensional model of the femoral head based on a target image of the femoral head including a necrotic area, where the three-dimensional model includes a proximal femur three-dimensional model and a necrotic bone three-dimensional model; creating an analysis model of the femoral head based on the three-dimensional model; and extracting the equivalent stress and total deformation of the weight-bearing area of the femoral head based on the analysis model and performing data analysis. The embodiment of the present invention solves the problem of low accuracy of the femoral head image analysis result in the prior art and improves the accuracy of the femoral head image analysis result.

[0021] The above method analyzes the image of the femoral head with an existing necrotic area and performs three-dimensional restoration and simulation of the necrotic femoral head. However, this method requires scanning the femoral head image under preset conditions. Since the image information obtained with different scanning parameters will vary, it will affect the result of image analysis, and the preset conditions cannot be customized for various femoral head situations, which limits the application scope of this method to a certain extent. In addition, the analysis of the femoral head weight-bearing area in this method is not combined with the acetabular lunate joint surface of the human body, so the necrosis distribution of the femoral head cannot be accurately obtained, and this method does not disclose how to obtain the acetabular lunate surface structure model.

[0022] In "Reconstruction of the three-dimensional structure of the hip joint with avascular necrosis of the femoral head based on CT tomographic images" (Liu Dengjun et al., Journal of Regional Anatomy and Operative Surgery, Vol. 20, No. 2), a method for reconstructing the three-dimensional structure of the hip joint with avascular necrosis of the femoral head based on CT tomographic images was proposed. The purpose was to explore a method for quickly and accurately reconstructing the three-dimensional structure of the hip joint with avascular necrosis of the femoral head through virtual reality technology. The method was based on the 64-slice spiral CT continuous tomographic two-dimensional images of the hip joint, and Mimics software was used to reconstruct the three-dimensional visualization structures of the acetabulum, proximal femur, femoral neck, and the diseased tissues of the femoral head respectively. The result was that the three-dimensional reconstructed image of the Dicom format data of the hip joint CT scan by Mimics medical image processing software had clear structures, could truly reproduce the structures of the acetabulum and the proximal femur, and was able to locate the diseased tissue sites and calculate the volume of the diseased tissues. The conclusion was that Mimics software could accurately reconstruct the three-dimensional stereoscopic structure of the hip joint with avascular necrosis of the femoral head based on the original Dicom data obtained from CT scans, providing an objective basis for the evaluation of the hip joint bone with avascular necrosis of the femoral head and the selection of treatment plans.

[0023] The above method shows the left and right acetabula in the three-dimensional structure, applies virtual reality technology to the reconstruction and analysis of the three-dimensional structure of the femoral head, and uses Mimics software to establish a three-dimensional model of the hip joint bony structure. However, the method for establishing the acetabular lunate surface structure model in this method is relatively complex, and the acetabular lunate surface structure model cannot be simply and effectively and accurately established through the acetabular lunate surface measurement module.

[0024] The patent document with the publication number WO2019034142A1 discloses a method, device, terminal, and storage medium for displaying a three-dimensional virtual image, belonging to the field of virtual reality technology. The method includes: obtaining a first model texture map and a second model texture map of the three-dimensional virtual image. The three-dimensional virtual image includes a first model and a second model. The first model texture map includes the texture data of each pixel point in the first model, and the second model texture map includes the texture data of each pixel point in the second model; determining the target area of the three-dimensional virtual image and setting the brightness of each pixel point in the target area in the shader to an equal value; rendering the first model texture map and the second model texture map through the shader so that the brightness of each pixel point in the rendered target area is equal. The embodiments of this invention can ensure that the brightness of the pixel points in the target area is equal, and the transition effect at the junction of the first model and the second model is natural without seams, improving the display effect.

[0025] The above invention discloses the content of forming a three-dimensional stereoscopic image through virtual reality technology with multiple models for imaging display from the perspective of an operator, but does not disclose how to simply and efficiently generate the acetabular lunate surface structure module through the acetabular lunate surface measurement module.

[0026] The patent document with the publication number CN104091365A discloses a method for reconstructing an acetabular tissue model for serialized hip joint CT images, which has the following steps: Fine contour formation step: Select the point with the maximum gradient on the perpendicular line of the tangent at any point on the rough circular femoral head contour on the selected initial CT slice; traverse the rough femoral head contour to obtain a contour point set of the point with the maximum gradient on each tangent perpendicular line; connect the points in the contour point set to form the fine contour of the femoral head tissue on this CT slice; Serial femoral head contour extraction step, serial acetabular image extraction step and three-dimensional reconstruction step. Based on the skeletal shape of the patient's individual hip joint, this invention obtains personalized relevant position parameters, performs acetabular segmentation in CT images, obtains accurate acetabular tissue images and three-dimensional models, and for subsequent personalized inverse modeling of artificial femoral head prostheses, it does not require prior knowledge obtained through training with other data sets, and the implementation is simple.

[0027] In the above acetabular model reconstruction method, the femoral head image in the CT scan image is removed from the acetabular and femoral head images in the three-dimensional space coordinates and the CT sequence images of the rough femoral head contour, leaving the acetabular image, and then 3D reconstruction is performed to obtain the 3D model of the acetabulum. However, this method requires a series of complex operations on data such as the fitting residuals of the point with the maximum gradient and each edge point, which is not simple enough, and it cannot generate an acetabular lunate surface model by eliminating isolated noise points through a triangular patch set.

[0028] In addition, on the one hand, there are differences in the understanding of those skilled in the art; on the other hand, although the inventor studied a large number of literatures and patents when making this invention, due to space limitations, all details and contents are not listed in detail. However, this does not mean that this invention does not possess the features of these prior arts. On the contrary, this invention already possesses all the features of the prior arts, and the applicant reserves the right to add relevant prior arts in the background art. Summary of the Invention

[0029] In view of the deficiencies in the prior art, the present invention provides an analysis method for an analysis device of femoral head integrity rate, the analysis device also includes a data processing device, the analysis method of the data processing device includes at least the following steps: based on CT images and MR images, multiple models including at least an original femoral head necrosis model, an original femoral head model, and an acetabulum lunate surface model are formed, and a first three-dimensional stereo image obtained after initial iteration and / or contour merging of the above multiple models through a virtual reality device is imaged and displayed from the perspective of an operator, a necrotic lateral weight-bearing area is obtained based on the three-dimensional stereo image, and a femoral lateral weight-bearing area is generated based on the original femoral head model, and the necrotic lateral weight-bearing area and the femoral lateral weight-bearing area are subsequently iterated and / or spatially registered with the first three-dimensional stereo image through the virtual reality device to obtain a second three-dimensional stereo image that can be imaged and displayed in a manner of binding constraints or decomposition and independent processing, and a first femoral lateral weight-bearing area integrity rate is obtained based on the necrotic lateral weight-bearing area and the femoral lateral weight-bearing area, so that one or more parameters can be optimized by performing virtual cutting, three-dimensional interaction or three-dimensional measurement based on the first femoral lateral weight-bearing area integrity rate.

[0030] Compared with traditional imaging examination tools, such as CT, MRI and other technologies, which can only provide static three-dimensional images, users still only have a flat viewing angle when watching, and cannot obtain data such as the distribution of femoral head necrosis and the necrosis rate in the weight-bearing area in a three-dimensional environment. The present invention can generate a three-dimensional image for analysis and processing based on CT images and MR images, and perform comprehensive analysis and judgment based on the original femoral head necrosis model, the original femoral head model and the acetabulum lunate model of the three-dimensional image, and generate accurate data on necrosis distribution and necrosis rate in the weight-bearing area.

[0031] In addition, the advantages of the femoral head integrity rate analysis device and analysis method provided by the present invention also include at least: 1. By inputting a three-dimensional stereo image for analysis and processing based on CT images and MR images, a three-dimensional model of the hip joint is established on a VR interactive device, and then a data processing device is used to perform osteotomy, rotation, varus and weight-bearing area integrity on the femur to provide corresponding data support for the planning of femoral head necrosis osteotomy surgery, so that the advantages and disadvantages of various surgical plans can be tested before the operation, which greatly improves the accuracy and efficiency of the surgical plan, increases the success rate of the operation, and effectively reduces the cost of preoperative preparation.

[0032] 2. Combine graphic image algorithms to calculate the integrity rate of the first lateral femoral weight-bearing area from two-dimensional images, and compare it with the integrity rate of the first lateral femoral weight-bearing area obtained from three-dimensional graphics. The two calculation methods are mutually verified to improve the necessary diagnosis of femoral necrosis rate surgery. For example, when the difference between the integrity rate of the second femur and the integrity rate of the first lateral femoral weight-bearing area is too large, the data processing device can prompt the user to recheck the integrity rate of the first lateral femoral weight-bearing area by sending a prompt and / or an alarm, preventing problems such as incorrect operations when the doctor adjusts the reference plane position and / or calculation errors when the data processing device decomposes the three-dimensional stereoscopic image model, which may cause the integrity rate value of the first lateral femoral weight-bearing area to be distorted.

[0033] 3. Based on CT images and MR images, generate three-dimensional images in real time. Through complex programs and high-performance graphics cards, the rendering speed is accelerated to reach the required frame rate for VR display. It enables surgeons to directly detect human structures through realistic 3D images in a virtual reality environment, perform virtual cutting, three-dimensional interaction, and three-dimensional measurement, make the most reasonable surgical plan, effectively improve the success rate of surgery, and protect the life and health of patients.

[0034] According to a preferred embodiment, the data processing device at least includes a necrotic femoral head measurement module and a normal femoral head measurement module. The steps for the original femoral head model to calibrate the original femoral head necrosis model at least include: the necrotic femoral head measurement module generates a first necrotic weight-bearing area, the normal femoral head measurement module generates a second necrotic weight-bearing area, a calibrated third necrotic weight-bearing area is generated by performing a Boolean union operation on the first necrotic weight-bearing area and the second necrotic weight-bearing area, and the necrotic lateral weight-bearing area is extracted through the third necrotic weight-bearing area.

[0035] According to a preferred embodiment, the steps for the data processing device to generate the first necrotic weight-bearing area and the second necrotic weight-bearing area at least include: the necrotic femoral head measurement module generates a necrotic surface model by extracting the non-overlapping area between the original femoral head necrosis model and the original femoral head model, and generates a first necrotic weight-bearing area by comparing it with the acetabular lunate surface model. The normal femoral head measurement module generates a first femoral head weight-bearing area by comparing the original femoral head model with the acetabular lunate surface model, and generates a second necrotic weight-bearing area composed of a set of noise points by extracting noise from the first femoral head weight-bearing area.

[0036] According to a preferred embodiment, generating the lateral femoral weight-bearing area at least includes the following steps: The normal femoral head measurement module can generate an independent patch set by traversing each triangular patch grid of the first femoral head weight-bearing area, perform isolated noise removal based on the independent patch set to generate a second femoral head weight-bearing area composed of the remaining triangular patch grids, and extract and generate the lateral femoral weight-bearing area based on the second femoral head weight-bearing area.

[0037] According to a preferred embodiment, the data processing device further includes an acetabular lunate surface measurement module. Generating the acetabular lunate surface model at least includes the following steps: The acetabular lunate surface measurement module extracts the hip bone image based on the three-dimensional stereoscopic image and traverses at least one vertex of the hip bone image. When the line segments formed by the vertices along the normal direction intersect the original femoral head necrosis model or the original femoral head model respectively, define the vertex as an acetabular point and extract it. When repeating the extraction of the acetabular points to form an acetabular point set, the acetabular lunate surface measurement module generates a triangular patch set composed of at least three vertices that are subsets of the acetabular point set by traversing at least one triangular patch of the hip bone image, and performs isolated noise removal based on the triangular patch set to generate the acetabular lunate surface model.

[0038] According to a preferred embodiment, the triangular patch at least includes a fixed edge and two deformable edges, and the fixed edge and the two deformable edges together form a rigid body elastic system.

[0039] According to a preferred embodiment, the third necrotic weight-bearing area extracts the necrotic lateral weight-bearing area through the medial-lateral differentiation reference plane, and the second femoral head weight-bearing area extracts and generates the lateral femoral weight-bearing area through the medial-lateral differentiation reference plane.

[0040] According to a preferred embodiment, the data processing device is connected to a VR interaction device. When the data processing device transmits the original femoral head necrosis model, the original femoral head model, and the acetabular lunate surface model to the VR interaction device, the VR interaction device is configured to be able to perform a rotation operation on the original femoral head necrosis model, the original femoral head model, and the acetabular lunate surface model through an input device and be observed.

[0041] According to a preferred embodiment, generating the integrity rate of the first lateral femoral weight-bearing area at least includes the following steps: generating the entire lateral weight-bearing area based on the necrotic lateral weight-bearing area and the lateral femoral weight-bearing area, and generating the integrity rate of the first lateral femoral weight-bearing area based on the area ratio of the lateral femoral weight-bearing area to the entire lateral weight-bearing area.

[0042] According to a preferred embodiment, the data processing device can generate the integrity rate of the complete lateral femoral weight-bearing area by performing image transformation on the CT image.

[0043] According to a preferred embodiment, an analysis device for the integrity rate of the femoral head at least includes: a scanning device for collecting CT images and a nuclear magnetic resonance device for collecting MR images. The analysis device further includes a data processing device, and the data processing device is configured to perform the following steps: forming multiple models including at least an original femoral head necrosis model, an original femoral head model, and an acetabular lunate surface model based on the CT image and the MR image, and imaging and displaying the first three-dimensional stereoscopic image obtained after initial iteration and / or contour merging of the above multiple models from the perspective of an operator through a virtual reality device, obtaining the necrotic lateral weight-bearing area based on the three-dimensional stereoscopic image, generating the lateral femoral weight-bearing area based on the original femoral head model, and performing subsequent iteration and / or spatial registration of the necrotic lateral weight-bearing area, the lateral femoral weight-bearing area, and the first three-dimensional stereoscopic image through the virtual reality device to obtain a second three-dimensional stereoscopic image that can be imaged and displayed in a manner that can be processed by binding constraints or decomposing independently, obtaining the first integrity rate of the lateral femoral weight-bearing area based on the necrotic lateral weight-bearing area and the lateral femoral weight-bearing area, so that one or more parameters can be optimized by performing virtual cutting, three-dimensional interaction, or three-dimensional measurement based on the first integrity rate of the lateral femoral weight-bearing area. Brief Description of the Drawings

[0044] Figure 1 is a simplified schematic connection diagram of the device for analyzing the integrity rate of the femoral head of the present invention;

[0045] Figure 2 is a simplified flowchart of the method for generating the first integrity rate of the lateral femoral weight-bearing area of the present invention;

[0046] Figure 3 is a simplified flowchart of the method for generating the second integrity rate of the lateral femoral weight-bearing area of the present invention;

[0047] Figure 4 is a simplified schematic connection diagram of the preferred VR interaction device of the present invention; and

[0048] Figure 5 is a simplified azimuth schematic diagram of the preferred vertex normal of the present invention.

[0049] List of Reference Numerals

[0050] 1: Scanning device 2: Nuclear magnetic resonance device

[0051] 3: Data processing device 4: VR interaction device

[0052] 11: CT image 21: MR image

[0053] 41: Input device 100: Original femoral head necrosis model

[0054] 102: Necrosis surface model 103: First necrotic weight-bearing area

[0055] 104: Second necrotic weight-bearing area 105: Third necrotic weight-bearing area

[0056] 200: Original femoral head model 201: Lateral femoral weight-bearing area

[0057] 202: First femoral head weight-bearing area 203: Second femoral head weight-bearing area

[0058] 300: Acetabular lunate surface model 400: Integrity rate of the first lateral femoral weight-bearing area

[0059] 401: Integrity rate of the second lateral femoral weight-bearing area 101: Necrotic lateral weight-bearing area

[0060] 42: Connection line Detailed implementation manners

[0061] The present invention will be described in detail below in conjunction with the appended Figures 1 to 5 drawings.

[0062] The vertex normal mentioned in the present invention: It is defined that when the coordinates of the three-dimensional vertex P are (x, y, z), as Figure 5 shown, the vector n(x1, y1, z1) after normalizing the coordinates of point P is the normal of point P.

[0063] The triangular patch mentioned in the present invention: It is defined as including at least one fixed edge and two deformable edges, and the fixed edge and the two deformable edges together form a rigid body elastic system. The two deformable edges can be used for finite element calculation. For example, by differentiating the triangular patch to infinitely approximate the unit element, the corresponding models of the actual hip bone and femur can be integrated infinitely approximately.

[0064] The medial and lateral differentiation reference plane mentioned in the present invention: It is defined as the plane where the hip bone in the acetabular fossa belongs along the direction of the gravity line, and can be used to distinguish the medial and lateral sides of the femoral head weight-bearing area. Doctors can determine the medial and lateral sides of the weight-bearing area by adjusting the position of the reference plane.

[0065] The Boolean union operation mentioned in the present invention: The Boolean operation is defined as a logical deduction method of digital symbolization, including union, intersection, and subtraction. This logical operation method is introduced in graphic processing operations to combine simple basic graphics to generate new shapes, and it has developed from two-dimensional Boolean operations to three-dimensional graphic Boolean operations. Among them, the Boolean union operation is defined as used to merge two models, and the intersecting part will be deleted. After the operation, the two objects will become one object.

[0066] Example 1

[0067] Example 1 of the present invention discloses an analysis method for the integrity rate of the femoral head. As Figure 1 shown, it at least includes a data processing device 3, and the data processing device 3 at least includes a necrotic femoral head measurement module and a normal femoral head measurement module. The analysis method at least includes the following steps:

[0068] S1: As Figure 2 shown, the data processing device 3 generates a first three-dimensional stereoscopic image for analysis and processing based on the CT image 11 and the MR image 21. The first three-dimensional stereoscopic image at least includes an original femoral head necrosis model 100, an original femoral head model 200, and an acetabular lunate surface model 300;

[0069] Preferably, the first three-dimensional stereoscopic image obtained by initial iteration and / or contour merging of the above-mentioned multiple models is imaged and displayed from the perspective of an operator. Since there are partially overlapping regions between the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300, the initial iteration method refers to performing multiple matches and fits between the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300 in pairs, so that the multiple models are integrated into the first three-dimensional stereoscopic image. Preferably, the multiple models are integrated to form the first three-dimensional stereoscopic image in such a way that the transparency of the partially overlapping regions between them is 50% - 80%, and the transparency of the remaining regions of each model except this part is 0%. Since there are partially contour-joined regions between the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300, the contour merging method refers to using the Sobel operator in image processing to perform edge detection on the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300, obtaining an edge detection region formed by connecting smooth curves, and performing multiple matches and fits between the multiple models, so that the multiple models are integrated into the first three-dimensional stereoscopic image. Both the initial iteration and / or the contour merging can be adjusted independently by the operator.

[0070] S2: Generate a necrotic surface model 102 based on the non-intersecting and non-overlapping regions of the original femoral head necrosis model 100 and the original femoral head model 200, and generate a first necrotic weight-bearing area 103 by comparing with the acetabular lunate surface model 300;

[0071] S3: Generate the first femoral head weight-bearing area 202 based on the comparison between the original femoral head model 200 and the acetabular lunate surface model 300, and generate a second necrotic weight-bearing area 104 composed of a noise point set by extracting noise points from the first femoral head weight-bearing area 202.

[0072] Preferably, the method of comparing the original femoral head model 200 with the acetabular lunate surface model 300 can be to traverse each triangular patch mesh on the surface of the original femoral head model 200. If the line segments formed by the three vertices extending along their respective normal directions intersect with the acetabular lunate surface model 300, then take out this patch and place it in the set, and the first femoral head weight-bearing area 202 is composed of all the triangular patch meshes in this set. Among them, the length of the three vertices in each triangular patch mesh on the surface of the original femoral head model 200 extending along their respective normal directions can be 0.010m - 0.015m.

[0073] Preferably, a triangular patch is defined as including at least one fixed edge and two deformable edges, and the fixed edge and the two deformable edges together form a rigid body elastic system. The two deformable edges can be used for finite element calculation. For example, by differentiating the triangular patch to infinitely approximate the unit element, the corresponding models of the actual hip bone and femur can be integrated infinitely closely.

[0074] S4: Generate the calibrated third necrotic weight-bearing area model 105 through the Boolean union operation of the first necrotic weight-bearing area 103 and the second necrotic weight-bearing area 104, and extract the necrotic lateral weight-bearing area 101 through the third necrotic weight-bearing area model 105.

[0075] S5: Generate an independent patch set by traversing each triangular patch mesh of the first femoral head weight-bearing area 202, eliminate isolated noise points based on the independent patch set to generate a second femoral head weight-bearing area 203 composed of the remaining triangular patch meshes, and extract and generate the femoral lateral weight-bearing area 201 based on the second femoral head weight-bearing area 203.

[0076] Preferably, the method for generating the set of independent patches may be to traverse each triangular patch grid in the first femoral head weight-bearing area 202. If the line segments formed by the three vertices of each triangular patch grid extending along their respective normal directions do not intersect the original femoral head necrosis model 100, then take out this patch and place it in the initial set of independent patches. Subsequently, traverse the initial set of independent patches. If the line segments formed by the three vertices of each traversed triangular patch extending along the opposite directions of their respective normal directions do not intersect the original femoral head necrosis model 100, take out this patch, and repeat the above actions until all triangular patch grids meeting this condition are screened out to form a set of independent patches, where: the length of the line segments formed by the three vertices of each triangular patch grid in the first femoral head weight-bearing area 202 extending along their respective normal directions may be 0.01 m - 0.02 m, and the length of the line segments formed by the three vertices of each triangular patch in the initial set of independent patches extending along the opposite directions of their respective normal directions may be 1 mm - 3 mm;

[0077] Preferably, through the virtual reality device, subsequent iteration and / or spatial registration are performed on the necrotic lateral weight-bearing area 101, the femoral lateral weight-bearing area 201, and the first three-dimensional stereoscopic image to obtain a second three-dimensional stereoscopic image that can be imaged and displayed in a manner that can be processed by binding constraints or decomposing independently. Since both the necrotic lateral weight-bearing area 101 and the femoral lateral weight-bearing area 201 are extracted from multiple models that make up the first three-dimensional stereoscopic image, the subsequent iteration method refers to, based on the first three-dimensional stereoscopic image obtained after the initial iteration, performing multiple matches and fits between the necrotic lateral weight-bearing area 101, the femoral lateral weight-bearing area 201, and the first three-dimensional stereoscopic image pairwise, and integrating them into a second three-dimensional stereoscopic image. Preferably, at least multiple areas including the necrotic lateral weight-bearing area 101 and the femoral lateral weight-bearing area 201 are integrated to form the second three-dimensional stereoscopic image in such a way that the transparency of the partial area where each of them overlaps with at least one model is 50% - 80% and the transparency of the remaining area after removing this partial area is 0%. Preferably, the spatial registration method refers to separately extracting regions for multiple regions and the first three-dimensional stereoscopic image, respectively obtaining the region features of each region, performing region matching through the obtained region features, and integrating them to form the second three-dimensional stereoscopic image. Preferably, instead of matching and fitting multiple regions with the first three-dimensional stereoscopic image, multiple regions are matched with each region of the first three-dimensional stereoscopic image through region feature matching, and the regions corresponding to multiple regions on the first three-dimensional stereoscopic image can be marked on the first three-dimensional stereoscopic image in different colors.

[0078] S6: Generate the entire lateral weight-bearing area based on the necrotic lateral weight-bearing area 101 and the femoral lateral weight-bearing area 201, and generate the first femoral lateral weight-bearing area integrity rate 400 based on the area ratio between the femoral lateral weight-bearing area 201 and the entire lateral weight-bearing area.

[0079] Preferably, the area of the necrotic lateral weight-bearing area 101 is defined as S1, the area of the femoral lateral weight-bearing area 201 is defined as S2, and the calculation formula for the integrity rate 400 of the first femoral lateral weight-bearing area is: Rate = S2 / (S1 + S2). Preferably, based on the necrotic lateral weight-bearing area 101 and the femoral lateral weight-bearing area 201, the integrity rate 400 of the first femoral lateral weight-bearing area is obtained, so that one or more parameters can be optimized by performing virtual cutting, three-dimensional interaction, or three-dimensional measurement based on the integrity rate 400 of the first femoral lateral weight-bearing area. Since the obtained second three-dimensional stereoscopic image (or simply referred to as the three-dimensional stereoscopic image) is obtained through a process of mutual matching of multiple models and multiple regions, each model, each region, and each model and each region are interconnected in a decomposable manner, so that the user can optimize the parameters of virtual cutting, three-dimensional interaction, and three-dimensional measurement of the obtained three-dimensional stereoscopic image through the input device 41. In particular, it refers to optimizing the parameters in the case of needing to obtain the necrotic area of the femoral head weight-bearing area. For example, when the user sets a virtual cutting plane to perform virtual cutting on the three-dimensional stereoscopic image, the parameters of the set virtual cutting plane are optimized based on the obtained integrity rate 400 of the first femoral lateral weight-bearing area, so that the necrotic area of the femoral head weight-bearing area obtained by the virtual cutting plane is more accurate.

[0080] Preferably, the data processing device 3 can be composed of a computer, a processor, a microprocessor controller, or programmable hardware including a storage component that can store or receive software or computer code. Preferably, the method according to the present invention can be implemented in hardware, firmware, or be implemented as software or computer code that can be stored in a recording medium such as a CDROM, RAM, floppy disk, hard disk, or magneto-optical disk, or be implemented as computer code originally stored in a remote recording medium or a non-transitory machine-readable medium and downloaded through a network and to be stored in a local recording medium, so that the method described herein can be stored as such software processing on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware such as an ASIC or FPGA. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code, such as RAM, ROM, flash memory, etc. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the processing method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the processing shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the processing shown herein. More preferably, the data processing device 3 can be a dedicated computer loaded with a virtual reality spinal surgery planning system, and the virtual reality spinal surgery planning system at least includes a necrotic femoral head measurement module, a normal femoral head measurement module, and an acetabular lunate surface measurement module.

[0081] According to a preferred embodiment, the data processing device 3 further includes an acetabular lunate surface measurement module. The steps for generating the acetabular lunate surface model 300 at least include the following:

[0082] S1: The acetabular lunate surface measurement module extracts the hip bone image based on the three-dimensional stereoscopic image and traverses each vertex of the hip bone image. When the line segments formed by the vertices along the normal direction intersect the original femoral head necrosis model 100 or the original femoral head model 200 respectively, the vertex is defined as an acetabular point and extracted. Wherein: the length of the normal extension direction of each vertex of the hip bone image can be 0.010m - 0.015m;

[0083] S2: When the above actions are repeated until a set of acetabular points is formed, the acetabular lunate surface measurement module traverses each triangular patch of the hip bone image to generate a set of triangular patches where all three vertices are subsets of the set of acetabular points. Based on the set of triangular patches, isolated noise points are removed to generate the acetabular lunate surface model 300 composed of the remaining triangular patch meshes.

[0084] According to a preferred embodiment, as Figure 4 shown, the data processing device 3 is connected to the VR interaction device 4. When the data processing device 3 transmits the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300 to the VR interaction device 4, the VR interaction device 4 is configured to be able to perform a rotation operation on the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300 through the input device 41 and be observed. Preferably, the VR interaction device 4 can achieve signal transmission with the data processing device 3 through the connection line 42. More preferably, the connection line can be an HDMI signal transmission line.

[0085] Preferably, the input device 41 can be composed of devices such as a keyboard, a mouse, and a laser pointer. Medical staff can perform auxiliary annotation on the original femoral head necrosis model 100 in the three-dimensional stereoscopic image through the keyboard and the mouse, and at the same time adjust the gray scale of the three-dimensional stereoscopic image to make the image more convenient for the user to observe, and adjust the position of the reference plane in the image to determine the inside and outside of the weight-bearing area. Preferably, the user can rotate and observe the three-dimensional stereoscopic image displayed by the VR interaction device 4 through the laser pointer while wearing 3D glasses.

[0086] More preferably, the user can form a selection area by establishing multiple planes in the three-dimensional stereoscopic image. Without moving the entire three-dimensional stereoscopic image, the selection area can be rotated separately, enabling more clear and accurate observation of the structures within the selection area, and performing virtual cutting, three-dimensional interaction, and three-dimensional measurement to make the most reasonable surgical plan, effectively improving the success rate of the surgery and protecting the patient's life and health.

[0087] According to a preferred embodiment, as Figure 3 shown, the data processing device 3 can generate the integrity rate 401 of the complete second lateral femoral weight-bearing area by performing image transformation on the CT image.

[0088] Preferably, the integrity rate 401 of the second lateral femoral weight-bearing area can be used to verify the integrity rate 400 of the first lateral femoral weight-bearing area. When the difference between the integrity rate 401 of the second femur and the integrity rate 400 of the first lateral femoral weight-bearing area is too large, the data processing device 3 can prompt the user to recheck the integrity rate 400 of the first lateral femoral weight-bearing area in the way of sending prompts and / or alarms, so as to prevent problems such as misoperation when the doctor adjusts the position of the reference plane and / or calculation errors when the data processing device 3 decomposes the three-dimensional stereoscopic image, which may cause distortion of the value of the integrity rate 400 of the first lateral femoral weight-bearing area.

[0089] According to a preferred embodiment, the third necrotic weight-bearing area model 105 extracts the necrotic lateral weight-bearing area 101 through the medial-lateral differentiation reference plane, and the second femoral head weight-bearing area 203 is extracted through the medial-lateral differentiation reference plane to generate the lateral femoral weight-bearing area 201.

[0090] Preferably, the medial-lateral differentiation reference plane is defined as the plane where the hip bone in the acetabular fossa belongs along the direction of the gravity line, and can be used to distinguish the medial and lateral sides of the femoral head weight-bearing area. The doctor can determine the medial and lateral sides of the weight-bearing area by adjusting the position of the reference plane.

[0091] It should be noted that according to the needs of implementation, each step described in the present application can be split into more steps, and two or more steps or partial operations of steps can also be combined into new steps to achieve the purpose of the present invention. At the same time, each functional module described in the present application can be split into more functional modules, and two or more functional modules or partial functions of functional modules can also be combined into new functional modules to achieve the purpose of the present invention.

[0092] Embodiment 2

[0093] This embodiment discloses an analysis device for the integrity rate of the femoral head. Without causing conflicts or contradictions, the whole and / or partial contents of the preferred embodiments of other embodiments can be used as supplements to this embodiment.

[0094] According to a preferred embodiment, the analysis device at least includes a scanning device 1 for collecting CT images 11 and a nuclear magnetic resonance device 2 for collecting MR images 21. The analysis device further includes a data processing device 3, which can generate a three-dimensional stereoscopic image for analysis and processing based on the CT image 11 and the MR image 21. The three-dimensional stereoscopic image at least includes an original femoral head necrosis model 100, an original femoral head model 200, and an acetabular lunate surface model 300. Preferably, the scanning device 1 can be one or more of a thermal tomography device, a far-infrared tomography device, and a computed tomography device.

[0095] According to a preferred embodiment, the data processing device 3 is configured as a necrotic femoral head measurement module and a normal femoral head measurement module. The necrotic femoral head measurement module calibrates the original femoral head necrosis model 100 based on the original femoral head model 200 and generates a necrotic lateral weight-bearing area 101. At the same time, the normal femoral head measurement module generates a femoral lateral weight-bearing area 201 based on the original femoral head model 200, and generates a first femoral lateral weight-bearing area integrity rate 400 based on the necrotic lateral weight-bearing area 101 and the femoral lateral weight-bearing area 201.

[0096] According to a preferred embodiment, the data processing device 3 is connected to a VR interaction device 4. When the data processing device 3 transmits the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300 to the VR interaction device 4, the VR interaction device 4 is configured to be able to perform a rotation operation on the original femoral head necrosis model 100, the original femoral head model 200, and the acetabular lunate surface model 300 through an input device 41 and be observed.

[0097] Preferably, the input device 41 can be composed of devices such as a keyboard, a mouse, and a laser pointer. Medical staff can assist in annotating the original femoral head necrosis model 100 in the three-dimensional stereoscopic image through the keyboard and mouse, and at the same time adjust the gray scale of the three-dimensional stereoscopic image to make the image more convenient for users to observe, and adjust the position of the reference plane in the image to determine the inside and outside of the weight-bearing area. Preferably, the user can rotate and observe the three-dimensional stereoscopic image displayed by the VR interaction device 4 through a laser pointer while wearing 3D glasses.

[0098] More preferably, the user can form a selection area by establishing multiple planes in the three-dimensional stereoscopic image. Without moving the entire three-dimensional stereoscopic image, the selection area can be rotated separately, enabling more clear and accurate observation of the structures within the selection area, and performing operations such as virtual cutting, three-dimensional interaction, and three-dimensional measurement to make the most reasonable surgical plan, effectively improving the success rate of the surgery and protecting the patient's life and health.

[0099] Preferably, compared with traditional imaging examination tools, such as CT, MRI and other technologies, which can only provide static three-dimensional images, the user still has only a planar viewing perspective when observing, and it is impossible to obtain data such as the necrosis distribution of the femoral head and the necrosis rate in the weight-bearing area in a three-dimensional environment. The present invention can generate a three-dimensional image for analysis and processing based on the CT image 11 and the MR image 21, and perform comprehensive analysis and judgment according to the original femoral head necrosis model 100, the original femoral head model 200 and the acetabular lunate surface model 300 of the three-dimensional image, so as to generate accurate data on the necrosis distribution and the necrosis rate in the weight-bearing area.

[0100] It should be noted that the above specific embodiments are exemplary. Those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the description and drawings of the present invention are illustrative and do not constitute a limitation on the claims. The protection scope of the present invention is defined by the claims and their equivalents.

Claims

1. A system for generating a structure model of the acetabular lunate surface, including an acetabular lunate surface measurement module, characterized in that, The acetabular lunate surface measurement module extracts the hip bone image based on the three-dimensional stereoscopic image and traverses at least one vertex of the hip bone image. When the line segments formed by the vertices along the normal direction intersect the original osteonecrosis of the femoral head model (100) or the original femoral head model (200) respectively, the vertex is defined as an acetabular point and extracted. When the acetabular points are repeatedly extracted to form a set of acetabular points, the acetabular lunate surface measurement module generates a set of triangular patches with at least three vertices being subsets of the set of acetabular points by traversing at least one triangular patch of the hip bone image. Based on the set of triangular patches, isolated noise points are removed to generate the acetabular lunate surface model (300).

2. The system according to claim 1, wherein The triangular patch includes at least one fixed edge and two deformable edges, and the fixed edge and the two deformable edges together form a rigid body elastic system.

3. The system according to claim 1, wherein The system generates the three-dimensional stereoscopic image for analysis and processing based on the CT image (11) and the MR image (12). The three-dimensional stereoscopic image includes at least the original osteonecrosis of the femoral head model (100), the original femoral head model (200), and the acetabular lunate surface model (300).

4. The system according to claim 3, wherein The system displays the first three-dimensional stereoscopic image obtained by initial iteration and / or contour merging of the original osteonecrosis of the femoral head model (100), the original femoral head model (200), and the acetabular lunate surface model (300) from the perspective of the operator through the virtual reality device.

5. The system according to claim 4, wherein The system further includes a VR interaction device (4). When the system transmits the acetabular lunate surface model (300) to the VR interaction device (4), the VR interaction device (4) is configured to be able to perform a rotation operation on the acetabular lunate surface model (300) through the input device and be observed.

6. A method for generating a structural model of the acetabular lunate surface, characterized in that, The method includes the following steps: S1 The acetabular lunate surface measurement module extracts the hip bone image based on the three-dimensional stereoscopic image and traverses each vertex of the hip bone image. When the line segments formed by the vertices along the normal direction intersect the original osteonecrosis of the femoral head model (100) or the original femoral head model (200) respectively, the vertex is defined as an acetabular point and extracted. S2 When the above actions are repeated until a set of acetabular points is formed, the acetabular lunate surface measurement module generates a set of triangular patches with all three vertices being subsets of the set of acetabular points by traversing each triangular patch of the hip bone image. Based on the set of triangular patches, isolated noise points are removed to generate the acetabular lunate surface model (300) composed of the remaining triangular patch meshes.

7. The method according to claim 6, characterized in that, The method further includes the following steps: Based on the CT image (11) and the MR image (12), multiple models including at least the original osteonecrosis of the femoral head model (100), the original femoral head model (200), and the acetabular lunate surface model (300) are formed, and the first three-dimensional stereoscopic image obtained by initial iteration and / or contour merging of the above multiple models is displayed from the perspective of the operator through the virtual reality device.

8. The method according to claim 6, wherein The triangular patch includes at least one fixed edge and two deformable edges, and the fixed edge and the two deformable edges together form a rigid body elastic system.

9. The method according to claim 8, wherein The original femoral head model (200) can be compared with the acetabular lunate surface model (300) through the following steps: Traverse each triangular patch grid on the surface of the original femoral head model (200). If the line segments formed by the three vertices extending along their respective normal directions intersect with the acetabular lunate surface model (300), take out this patch and place it in a set, and all the triangular patch grids in this set form the first femoral head weight-bearing area (202).

10. The method according to claim 9, wherein The method generates an independent patch set by traversing each triangular patch grid in the first femoral head weight-bearing area (202). The method of generating the independent patch set is as follows: Traverse each triangular patch grid in the first femoral head weight-bearing area (202). If the line segments formed by the three vertices extending along their respective normal directions do not intersect with the original femoral head necrosis model (100), take out this patch and place it in the initial independent patch set; Traverse the initial independent patch set. If the line segments formed by the three vertices of each traversed triangular patch extending along the opposite directions of their respective normals do not intersect with the original femoral head necrosis model (100), take out this patch, and repeat the above operation until all triangular patch grids meeting this condition are screened out to form the independent patch set.

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