CN-121987237-A - Joint angle change track determination method and system and X-ray camera

CN121987237ACN 121987237 ACN121987237 ACN 121987237ACN-121987237-A

Abstract

The present disclosure provides a joint angle change trajectory determination method, system, and X-ray camera. Embodiments of the present disclosure may be implemented in relation to the field of dynamic knee radiographic image processing techniques. The joint angle change track determining method comprises the steps of obtaining dynamic knee joint X-ray photographic images to be processed, wherein the dynamic knee joint X-ray photographic images to be processed are multiple knee joint X-ray photographic image sequences shot by the same testee in a leg movement state, respectively determining joint angular points corresponding to each knee joint X-ray photographic image in the multiple knee joint X-ray photographic image sequences to obtain multiple moment joint angular points, and determining joint angle change tracks based on the multiple moment joint angular points and the corresponding multiple moment angles. To determine the trajectory of the joint angle change.

Inventors

GUO PENG
YANG YINGJIAN
WU TIANQI
Zeng Nanrong
ZHENG JIE

Assignees

深圳蓝影医学科技股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260130

Claims (10)

1.A method for determining a trajectory of a change in joint angle, comprising: Acquiring dynamic knee joint X-ray photographic images to be processed, wherein the dynamic knee joint X-ray photographic images to be processed are a plurality of knee joint X-ray photographic image sequences shot by the same subject in a leg movement state; respectively determining joint angular points corresponding to each knee joint X-ray photographic image in the knee joint X-ray photographic image sequences to obtain multi-moment joint angular points; and determining a joint angle change track based on the multi-time joint angle points and the corresponding multi-time angles.
2. The method of claim 1, wherein the determining joint angular points corresponding to each of the plurality of knee joint radiographs in the plurality of knee joint radiograph sequences to obtain the multi-temporal joint angular points includes determining joint angular points between the central axis of femur and the central axis of tibia in each of the plurality of knee joint radiographs based on the central axis of femur and the central axis of tibia corresponding to each of the plurality of knee joint radiographs in the plurality of knee joint radiographs, respectively, and/or, The method comprises respectively determining joint angular points between the central axis of femur and the central axis of tibia in each knee joint X-ray photographic image according to the central axis of femur and the central axis of tibia corresponding to each knee joint X-ray photographic image in the knee joint X-ray photographic image sequence, establishing a polar coordinate equation set according to the central axis of femur and the central axis of tibia corresponding to each knee joint X-ray photographic image in the knee joint X-ray photographic image sequence, determining joint angular points between the central axis of femur and the central axis of tibia in each knee joint X-ray photographic image by utilizing the polar coordinate equation set, and/or, The method comprises the steps of determining whether coordinates corresponding to unique solutions are in a knee joint X-ray photographic image to be processed or not if the unique solutions exist in the polar coordinate equation sets, determining the coordinates corresponding to the unique solutions as joint points between the femoral central axis and the tibial central axis if the unique solutions are in the knee joint X-ray photographic image to be processed, determining the joint points corresponding to the joint points based on second non-zero coordinates corresponding to the femoral central axis and the tibial mask boundary image, determining the joint points corresponding to the tibial central axis and the tibial central point if the unique solutions are not in the knee joint X-ray photographic image to be processed or the polar coordinate equation sets, and determining the joint points corresponding to the joint points based on first non-zero coordinates corresponding to the femoral mask boundary in the femoral central axis and the femoral mask boundary image, the central point coordinates of the femoral central axis and the tibial central point of the knee joint X-ray photographic image to be processed.
3. The method according to claim 2, wherein the determining the first coordinate point corresponding to the joint angular point based on the first non-zero coordinates corresponding to the femoral mask boundary in the femoral mid-axis and femoral mask boundary image, the central point coordinates of the femoral mid-axis and the knee radiographic image to be processed, includes calculating a first medial axis distance from each non-zero coordinate in the first non-zero coordinates to the femoral mid-axis according to the first non-zero coordinates corresponding to the femoral mask boundary in the femoral mid-axis and femoral mask boundary image, determining a selected set of femoral mask boundary non-zero coordinates for which the first medial axis distance from each non-zero coordinate in the first non-zero coordinates to the femoral mid-axis is within a preset pixel size length, calculating a first central distance from each selected femoral mask boundary non-zero coordinate in the selected set of femoral mask boundary non-zero coordinates to the central point coordinates of the knee radiographic image to be processed, configuring a selected femoral mask boundary non-zero coordinate corresponding to a minimum central distance in the first central distances as the first central point, The method comprises the steps of determining second coordinate points corresponding to joint angular points based on second non-zero coordinates corresponding to tibia mask boundaries in the tibia central axis and tibia mask boundary images, determining a selected tibia mask boundary non-zero coordinate set, in which the distance from each non-zero coordinate in the second non-zero coordinate to the tibia central axis is within a preset pixel size length, of each non-zero coordinate in the second non-zero coordinate set, calculating second center distances from each selected tibia mask boundary non-zero coordinate in the selected tibia mask boundary non-zero coordinate set to the center point coordinates of the knee joint X-ray photographic images to be processed, and configuring selected tibia mask boundary non-zero coordinates corresponding to the minimum center distances in the second center distances as second coordinate points.
4. The joint angle change track determining method according to claim 2 or 3, wherein the method comprises the steps of respectively extracting femur mask boundary images corresponding to femur masks in femur region mask images corresponding to each knee joint X-ray photographic image in the knee joint X-ray photographic image sequences according to femur central axes corresponding to each knee joint X-ray photographic image in the knee joint X-ray photographic image sequences, determining first boundary lines and second boundary lines in two sides of femur or femur cortex based on non-zero coordinates of femur mask boundaries of the femur mask boundary images, and determining the femur central axes based on the first boundary lines and the second boundary lines.
5. The method according to claim 4, wherein determining the femoral central axis based on the first boundary line and the second boundary line includes determining a first direction vector corresponding to the first boundary line and a second direction vector corresponding to the second boundary line, respectively, dot multiplying the first direction vector and the second direction vector by a femoral component direction vector corresponding to the femoral region mask image, respectively, to obtain a first product corresponding to the first direction vector and a second product corresponding to the second direction vector, inverting the first direction vector in the direction if the first product is smaller than a first predetermined value, not processing the first direction vector if the second product is smaller than a second predetermined value, inverting the second direction vector in the direction, not processing the second direction vector, adding the first direction vector corresponding to the inversion or non-processing and the second direction vector corresponding to the inversion or non-processing, and obtaining a first direction vector and/or bisecting the femoral central axis based on the first boundary line and/or the femoral central axis line, The method comprises the steps of determining a femoral central axis based on the first boundary line, the second boundary line and the bisector direction vector, determining the femoral central axis corresponding to a third coordinate equation based on the intersection point, the bisector direction vector and the third coordinate equation corresponding to the bisector direction vector if the intersection point exists between the first boundary line and the second boundary line, otherwise, determining the femoral central axis corresponding to the third coordinate equation according to the midpoint corresponding to the perpendicular line segment between the first boundary line and the second boundary line, the bisector direction vector and the third coordinate equation corresponding to the bisector direction vector.
6. The method according to any one of claims 2 to 5, wherein the respective central axis of tibia corresponding to each of the plurality of knee radiographs in the knee radiographic image sequence includes extracting respective tibial mask boundary images corresponding to tibial masks in the tibial region mask images corresponding to each of the plurality of knee radiographs in the knee radiographic image sequence, determining third and fourth boundary lines in boundary lines on both sides of tibia or tibial cortex based on the tibial mask boundary images and the tibial mask boundary non-zero coordinates of the tibial mask boundary images, and/or, The method comprises determining one or two boundary lines of a third boundary line and a fourth boundary line in boundary lines on two sides of tibia or tibia cortex based on the tibia mask boundary image and non-zero coordinates of the tibia mask boundary image, performing polar coordinate Hough transformation on the tibia mask boundary image, determining the most probable third boundary line and fourth boundary line to be modified on the outermost side of tibia or tibia cortex, determining whether the third boundary line and the fourth boundary line to be modified are parallel, and if the intersection point of the third boundary line and the fourth boundary line to be modified is not parallel and is in the tibia mask image, modifying the third boundary line and the fourth boundary line to obtain one or two boundary lines of the third boundary line and the fourth boundary line based on the tibia mask boundary image respectively, and/or, The method comprises respectively correcting a third boundary line to be corrected and the fourth boundary line to obtain one or two boundary lines of the third boundary line and the fourth boundary line based on the tibia mask boundary image, determining a mirror image straight line based on the knee joint X-ray photographic image to be processed corresponding to the tibia mask boundary image, mirroring tibia mask boundaries in the tibia mask boundary image with the mirror image straight line as a symmetry axis to obtain tibia mask boundary mirroring, respectively correcting the third boundary line to be corrected and the fourth boundary line to obtain one or two boundary lines of the third boundary line and the fourth boundary line based on the tibia mask boundary image and the tibia mask boundary mirroring, and/or, The method comprises the steps of correcting a third boundary line to be corrected and the fourth boundary line to obtain one or two boundary lines of the third boundary line and the fourth boundary line based on the tibia mask boundary and the tibia mask boundary mirror image respectively, and comprises the steps of performing polar coordinate Hough transformation on the tibia mask boundary and the tibia mask boundary mirror image to determine a plurality of most probable straight lines, and if any two straight lines in the plurality of most probable straight lines are parallel, configuring any one or two parallel straight lines as one or two boundary lines of the third boundary line and the fourth boundary line.
7. The method according to claim 6, wherein the correcting the third boundary line to be corrected and the fourth boundary line to obtain one or two boundary lines of the third boundary line and the fourth boundary line based on the tibial mask boundary and the tibial mask boundary mirror image respectively, further comprises configuring one or two boundary lines of the third boundary line and the fourth boundary line as one or two boundary lines of the two lines corresponding to any two lines which are not parallel and are not parallel if the intersection point corresponding to any two lines which are not parallel in the plurality of most probable straight lines is outside the tibial mask image, and/or, The method comprises determining one or two boundary lines of a third boundary line and a fourth boundary line in boundary lines on two sides of tibia or tibia cortex based on the tibia mask boundary image and the tibia mask boundary image, and further comprises, if the boundary lines are parallel, not correcting the third boundary line and the fourth boundary line, respectively configuring the third boundary line and the fourth boundary line as one or two boundary lines of the third boundary line and the fourth boundary line, respectively, if the boundary lines are not parallel and the intersection point of the third boundary line and the fourth boundary line is outside the tibia mask image, not correcting the third boundary line and the fourth boundary line, respectively configuring the third boundary line and the fourth boundary line as one or two boundary lines of the third boundary line and the fourth boundary line, Before the third boundary line to be corrected and the fourth boundary line to be corrected are corrected based on the tibia mask boundary image respectively, the method comprises the steps of determining tibia length based on the tibia mask image or a tibia mask boundary image corresponding to the tibia mask image, correcting the third boundary line to be corrected and the fourth boundary line to be corrected based on the tibia mask boundary image respectively if the tibia length is smaller than a preset tibia length, otherwise, not correcting the third boundary line to be corrected and the fourth boundary line to be corrected, and configuring the third boundary line to be corrected and the fourth boundary line to be one or two boundary lines of a third boundary line and a fourth boundary line respectively.
8. The method according to any one of claims 1 to 7, wherein calculating the joint angle between the femur and the tibia based on the joint point and a sixth direction vector corresponding to the central axis of the tibia and a third direction vector corresponding to the central axis of the femur comprises calculating the joint angle between the femur and the tibia using a sixth direction vector corresponding to the central axis of the tibia and a third direction vector corresponding to the central axis of the femur and a third direction vector corresponding to the central axis of the tibia and/or, The dot product formula is based on, and the joint angle between the femur and the tibia is calculated by using the joint angular point, a third direction vector corresponding to the central axis of the femur and a sixth direction vector corresponding to the central axis of the tibia, and the dot product formula is based on, and the joint angle between the femur and the tibia is calculated by using the joint angular point, the third direction vector and the sixth direction vector, and/or the dot product formula is based on The method comprises the steps of determining a femoral middle shaft and a tibial middle shaft corresponding to initial moment joint angles in the multi-moment joint angles, configuring the initial moment joint angles corresponding to the initial moment joint angles as axial points, configuring the femoral middle shaft or the tibial middle shaft corresponding to the initial moment joint angles as fixed axes corresponding to the axial points, keeping the coordinate positions of the fixed axes and the axial points unchanged, and rotating the fixed axes to the tibial middle shaft or the femoral middle shaft corresponding to other moment angles according to the multi-moment angles or other moment angles except the initial moment angles in the multi-moment angles respectively to determine joint angle change tracks; Before the joint angle change track is determined based on the multi-moment joint angular points and the corresponding multi-moment angles, the method comprises the step of calculating joint angles between the femur and the tibia in each knee joint X-ray photographic image based on the joint angular points, third direction vectors corresponding to the central axes of the femur and sixth direction vectors corresponding to the central axes of the tibia.
9. A joint angle change trajectory determination system, comprising: The method comprises the steps of acquiring dynamic knee joint X-ray photographic images to be processed, wherein the dynamic knee joint X-ray photographic images to be processed are multiple knee joint X-ray photographic image sequences shot by the same examinee in a leg movement state, respectively determining joint angular points corresponding to each knee joint X-ray photographic image in the multiple knee joint X-ray photographic image sequences to obtain multi-time joint angular points, and determining joint angular change tracks based on the multi-time joint angular points and corresponding multi-time angles of the multi-time joint angular points, or comprises a processor, a memory used for storing executable instructions of the processor, wherein the processor is configured to call the instructions stored in the memory to execute the joint angular change track determining method according to any one of claims 1-8, or comprises a computer readable storage medium, on which a computer program/instruction and a bit stream are stored, the computer program/instruction is executed by the processor to realize the joint angular change track determining method according to any one of claims 1-8, or comprises a computer program/instruction which is configured to realize the joint angular change track determining method according to any one of claims 1-8, and the computer program/or the bit stream is configured to realize the joint change track determining method according to any one of the computer program/instructions.
10. The X-ray camera of claim 9, comprising a joint angle change trajectory determination system.

Description

Joint angle change track determination method and system and X-ray camera Technical Field The disclosure relates to the technical field of dynamic knee joint radiography image processing, in particular to a method and a system for determining a joint angle change track and an X-ray camera. Background Determining knee joint angle change track has important significance for clinical diagnosis, disease evaluation, sports medicine, rehabilitation therapy and biomechanical research. By analyzing the knee joint angle change track, abnormal joint movement, such as poor patella track, narrow joint clearance, ligament injury and the like, can be found. For example, patients with patellofemoral pain syndrome often have abnormal patella movement trajectories, which are manifested as lateral shifts or inclinations, and are helpful for early diagnosis and disease assessment in combination with knee joint angle change trajectory analysis. Degenerative diseases such as knee osteoarthritis can cause wear and tear of joint cartilage and hyperosteogeny, and influence the change track of joint angles. Monitoring the track changes can reflect disease progression and provide basis for treatment scheme adjustment. In physical training, know sportsman knee joint angle variation track, can pertinently adjust action technique, reduce joint injury risk, improve motion efficiency. For example, in running, jumping and other projects, the knee joint bending and stretching angle and track are reasonably controlled, so that the joint pressure can be reduced, and the athletic performance can be improved. For the patient with knee joint injury or postoperative, a personalized rehabilitation scheme is formulated according to the knee joint angle change track. The normal movement track of the joint is recovered through training, the muscle strength is enhanced, the joint function recovery is promoted, and the secondary injury is prevented. The research of the knee joint angle change track is helpful for deeply understanding the mechanical principle of the joint under different motion states, such as the synergistic effect of the muscles of quadriceps femoris, popliteal cord muscle and the like, and the contribution of the structures of ligaments, joint capsules and the like to the stability of the joint. Based on the research result of the knee joint angle change track, medical instruments such as knee joint prosthesis, orthosis and the like which are more in accordance with human engineering are designed, the functionality and the comfort of the medical instruments are improved, and the life quality of patients is improved. Compared to Computed Tomography (CT), magnetic Resonance (MR) and other imaging modalities, X-rays are more suitable for the preliminary assessment of degenerative osteoarthritis and pain from car accident injuries. As the most widely used basic imaging method in orthopaedics, X-ray radiography has become the imaging device of choice for preliminary examination of knee joints (e.g., detection of fractures, dislocation and other abnormalities) and evaluation of clinical conditions such as osteoarthritis and bone destruction, due to its wide availability, low cost and rapid convenience. However, X-ray, CT and MR imaging of the knee joint do not conflict, but are complementary. In particular, since X-rays are an overlapping imaging modality, the display of intra-articular structures presents blind spots, which are still lacking in detecting subtle or hidden fractures. Thus, a slight fracture or bone injury may be detected from a three-dimensional (3D) knee CT image. From the 3D knee CT images, bone lesions and tumors around the knee can be observed from multiple angles. However, 3D knee CT images show less diagnostic sensitivity to changes in muscles and ligaments surrounding the knee, especially in cases where cartilage changes or bone hyperplasia have not occurred. Similar to CT, MR imaging is also multiparameter, multiplanar and multidirectional, with the resolution of soft tissue being higher than that of bone. Clinical examination of cartilage, meniscus or muscle ligament injury, synovitis and joint effusion can be performed from 3D knee MR images. However, MRI is expensive, time consuming, and the device operation is complex. Meanwhile, information on knee joint movement functions is not currently available from MRI. In contrast to dynamic knee radiography, static knee X-ray images taken at a single instant lack information of knee motion, which is detrimental to assessing the motion function of the knee. Dynamic knee radiography can capture the motion trail of the knee joint, and is expected to be used for analysis of the knee joint motion function. Therefore, a technical scheme for determining the correspondence of the joint angle change track based on the dynamic knee joint X-ray photographic image is urgently needed to solve the technical problems that the existing lack of an effective quantitative determination m