Single-condyle surgery prosthesis planning method and device and computer equipment

Abstract

The embodiment of the invention is suitable for the technical field of computer-aided medical treatment and surgical planning, and provides a single-condyle surgical prosthesis planning method and device and computer device.The method comprises the steps that parameter information of a prosthesis to be planned is obtained, and the parameter information comprises the osteotomy amount; according to the parameter information, determining a placement position of the prosthesis in a pre-constructed three-dimensional model; calculating a coverage rate between a prosthesis section and a corresponding bone section in the three-dimensional model when the prosthesis is located at the placement position; according to the coverage rate, a target prosthesis is determined from the multiple to-be-planned prostheses, and preoperative planning of the unicompartmental condyle operation is carried out based on the target prosthesis. By the adoption of the method, the posture of the prosthesis can be automatically planned according to the osteotomy amount of the prosthesis, then the optimal prosthesis is selected for preoperative planning through calculation of the coverage rate of the section of the prosthesis, and the precision and safety of single-condyle surgery prosthesis planning are guaranteed.

Description

Technical Field

[0001] The embodiments of the present application belong to the technical field of computer-aided medical and surgical planning, and particularly relate to a unicompartmental surgical prosthesis planning method, device and computer equipment. Background Technique

[0002] Unicompartmental knee arthroplasty (UKA) is a surgery for treating injuries or degenerations in specific regions of the knee joint. By removing the diseased cartilage and part of the bone mass and implanting a prosthesis, it can help patients recover corresponding functions after the surgery. Preoperative prosthesis planning can provide an accurate surgical plan for intraoperative replacement.

[0003] In the prior art, the prosthesis planning for unicompartmental knee arthroplasty mainly determines the placement position of the prosthesis based on iterative closest point (ICP) registration, which not only takes a long time, but also does not fully consider the characteristics of the prosthesis itself during the planning process, which may lead to planning errors and affect the surgical effect. Summary of the Invention

[0004] In view of this, the embodiments of the present application provide a unicompartmental surgical prosthesis planning method, device and computer equipment, which can automatically plan the pose of the prosthesis according to the osteotomy amount of the prosthesis, and then select the best prosthesis for preoperative planning by calculating the coverage rate of the prosthesis cross-section, ensuring the accuracy and safety of unicompartmental surgical prosthesis planning.

[0005] The first aspect of the embodiments of the present application provides a unicompartmental surgical prosthesis planning method, including: Obtain the parameter information of the prosthesis to be planned, the prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount; Determine the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information; Calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position, and the coverage rate represents the proportion of the intersection plane of the prosthesis cross-section and the bone cross-section in the bone cross-section; Determine the target prosthesis from multiple prostheses to be planned according to the coverage rate, and perform preoperative planning for unicompartmental surgery based on the target prosthesis.

[0006] The second aspect of the embodiments of the present application provides a unicompartmental surgical prosthesis planning device, including: A parameter information acquisition module, configured to acquire the parameter information of the prosthesis to be planned, the prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount; A placement position determination module, configured to determine the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information; A coverage rate calculation module, configured to calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position, where the coverage rate represents the proportion of the intersection plane of the prosthesis cross-section and the bone cross-section in the bone cross-section; A preoperative sizing module, configured to determine a target prosthesis from multiple prostheses to be planned according to the coverage rate, and perform preoperative planning for unicompartmental surgery based on the target prosthesis.

[0007] A third aspect of the embodiments of the present application provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the computer device implements the method described in the first aspect above.

[0008] A fourth aspect of the embodiments of the present application provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a computer, the method described in the first aspect above is implemented.

[0009] A fifth aspect of the embodiments of the present application provides a computer program product, including a computer program. When the computer program runs, the method described in the first aspect above is executed.

[0010] Compared with the prior art, the embodiments of the present application have the following beneficial effects: In the embodiments of the present application, by obtaining the parameter information of the prosthesis to be planned including the osteotomy amount, the computer device can determine the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information of the prosthesis. In this way, the computer device can calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section when the prosthesis is placed in the above placement position, so that the target prosthesis suitable for the patient can be determined according to the coverage rate. The computer device can perform preoperative planning for unicompartmental surgery based on the target prosthesis to obtain the best surgical plan. By automatically setting the initial position of the prosthesis and adjusting the pose of the prosthesis based on parameters such as the osteotomy amount, the embodiments of the present application can fully consider the shape of the prosthesis to be implanted and the osteotomy amount in the preoperative planning stage, so as to determine the optimal prosthesis model, improve the speed and accuracy of unicompartmental surgery prosthesis planning, and improve the safety of the surgery. Description of the Drawings

[0011] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0012] Figure 1 It is a schematic diagram of a unicompartmental surgical prosthesis planning method provided by an embodiment of the present application; Figure 2 It is a schematic diagram of a possible implementation manner of S102 in a unicompartmental surgical prosthesis planning method provided by an embodiment of the present application; Figure 3 It is a schematic diagram of a femoral landmark point provided by an embodiment of the present application; Figure 4 It is a schematic diagram of a tibial landmark point provided by an embodiment of the present application; Figure 5 It is a schematic diagram of a possible implementation manner of S1023 in a unicompartmental surgical prosthesis planning method provided by an embodiment of the present application; Figure 6 It is a schematic diagram of a femoral prosthesis and a tibial prosthesis provided by an embodiment of the present application; Figure 7 It is a schematic diagram of a prosthesis placement position provided by an embodiment of the present application; Figure 8 It is a schematic diagram of a unicompartmental surgical prosthesis planning process provided by an embodiment of the present application; Figure 9 It is a schematic diagram of a unicompartmental surgical prosthesis planning device provided by an embodiment of the present application; Figure 10 It is a schematic diagram of a computer device provided by an embodiment of the present application. Detailed implementation manners

[0013] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are presented to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0014] The following uses specific embodiments to illustrate the technical solutions of the present application.

[0015] Referring to Figure 1 , a schematic diagram of a unicompartmental surgical prosthesis planning method provided by an embodiment of the present application is shown, and it may specifically include the following steps: S101. Obtain the parameter information of the prosthesis to be planned. The prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount.

[0016] It should be noted that this method can be applied to a computer device, that is, the execution subject of the embodiments of the present application can be a computer device. By executing the various steps of the planning method provided by the embodiments of the present application, the computer device can fully consider information such as the shape and osteotomy amount of the prosthesis before surgery, determine the optimal prosthesis available for intraoperative use, and use it for preoperative planning to obtain an accurate preoperative planning scheme.

[0017] The above computer device can be any type of electronic device capable of performing preoperative planning, such as a computer-aided medical device or other desktop computers, laptop computers, etc. that can carry out the corresponding function implementation. The embodiments of the present application do not limit the type of the computer device.

[0018] The scenario applicable to this method can be the preoperative planning stage of unicompartmental knee arthroplasty. Therefore, the surgeries mentioned in the embodiments of the present application all refer to unicompartmental knee arthroplasty. During the process of unicompartmental knee arthroplasty, the doctor needs to remove the diseased cartilage and part of the bone mass at the patient's knee joint and implant a prosthesis at the resection site. The preoperative planning stage is to plan and determine the prosthesis to be used and how to implant the prosthesis, etc., to form a complete planning scheme for guiding the doctor's surgical operation. The prostheses required for unicompartmental knee arthroplasty include two types: a femoral prosthesis and a tibial prosthesis. Among them, the femoral prosthesis needs to be implanted in the resected femoral area to replace the resected femur, and the tibial prosthesis needs to be implanted in the resected tibial area. Unless otherwise specified, the prostheses mentioned in the embodiments of the present application all include a femoral prosthesis and a tibial prosthesis.

[0019] In the embodiments of the present application, the prosthesis to be planned can be one of multiple available models. The computer device can determine the most suitable prosthesis for intraoperative use, that is, the target prosthesis, from multiple models by executing this method, and complete the preoperative planning of the surgical plan based on the target prosthesis. That is to say, the computer device can evaluate multiple models of prostheses, determine the most suitable target prosthesis, and plan how to implant the target prosthesis during the operation.

[0020] In the preoperative planning stage, the computer device can obtain the parameter information of the prosthesis to be planned. Usually, for available prostheses, after the manufacturer of the prosthesis completes the production of this type of prosthesis, it can provide various parameter information of this type of prosthesis to the user. These parameter information can include the coordinate system of the prosthesis itself, i.e., the prosthesis coordinate system, the position information of each landmark point on the prosthesis, each cross-section of the prosthesis and its normal vector direction, the recommended osteotomy amount during the operation using this prosthesis, etc. These parameter information can be organized into a readable file for the computer device to use during preoperative planning. Specifically, the computer device can read the parameter information of the femoral prosthesis and tibial prosthesis to be planned or evaluated currently from the readable file.

[0021] S102. Determine the placement position of the prosthesis in the pre-constructed three-dimensional model according to the parameter information.

[0022] In the embodiment of the present application, the preoperative planning can be performed based on a pre-constructed three-dimensional model, and this three-dimensional model can be a three-dimensional model of the patient's surgical site. Exemplarily, before the operation, an imaging device can be used to scan the patient to obtain medical images of the surgical site, i.e., the patient's knee joint. A three-dimensional model of the knee joint can be established through three-dimensional reconstruction. In one example, this three-dimensional model can specifically be a three-dimensional model of the femur and tibia at the knee joint.

[0023] After obtaining the parameter information of the prosthesis, the computer device can determine the placement position of the prosthesis in the above-mentioned pre-constructed three-dimensional model according to the parameter information. Since the prosthesis in the embodiment of the present application includes a femoral prosthesis and a tibial prosthesis, the computer device can determine the placement position of the femoral prosthesis and the placement position of the tibial prosthesis in the three-dimensional model respectively according to the parameter information of the femoral prosthesis and the parameter information of the tibial prosthesis.

[0024] In the embodiment of the present application, the computer device can determine an initial position and place the prosthesis at this initial position during the planning stage, and then move the prosthesis placed at the initial position in combination with parameter information such as the shape and osteotomy amount of the prosthesis to move the prosthesis to the final placement position. The above-mentioned final placement position after movement is also the actual implantation position of the prosthesis during the operation obtained by the planning.

[0025] In a possible implementation manner of the embodiment of the present application, as Figure 2 shown, in S102, determining the placement position of the prosthesis in the pre-constructed three-dimensional model according to the parameter information can specifically include the following steps S1021 - S1023: S1021. Establish a coordinate system based on the selected landmark points.

[0026] In the embodiments of the present application, in order to achieve accurate preoperative planning, a computer device may establish corresponding coordinate systems for the surgical site of the patient's knee joint, namely the femoral coordinate system and the tibial coordinate system. The computer device can establish the femoral coordinate system and the tibial coordinate system based on the selected landmark points. Specifically, the computer device can establish the femoral coordinate system based on the selected femoral landmark points and the tibial coordinate system based on the selected tibial landmark points.

[0027] In the embodiments of the present application, the above-mentioned landmark points may be manually selected by a doctor in the three-dimensional model after the computer device completes the three-dimensional model reconstruction of the femur and tibia; or, the computer device may also automatically select each landmark point available for coordinate system construction through the recognition of the three-dimensional model. The embodiments of the present application do not limit this.

[0028] As Figure 3 and Figure 4 shown, they are respectively schematic diagrams of a femoral landmark point and a tibial landmark point provided by the embodiments of the present application. Among them, Figure 3 the femoral landmark points shown may include the center point 301 of the femoral head, the lateral epicondyle point 302, the medial epicondyle point 303, the lateral point 304 of the distal femur, the medial point 305 of the distal femur, the lateral point 306 of the posterior condyle of the femur, the medial point 307 of the posterior condyle of the femur, and the center point 308 of the distal femur, etc. Figure 4 the tibial landmark points shown may include the lateral condyle point 401 of the tibia, the medial condyle point 402 of the tibia, the center point 403 of the tibial plateau, the tibial tuberosity point 404, the center point 405 of the PCL insertion, the lateral point 406 of the tibial plateau, and the medial point 407 of the tibial plateau, etc. It should be noted that Figure 3 and Figure 4 the positions of each landmark shown are only an example, and the actual positions of each landmark point on the femur and tibia may have errors compared with Figure 3 or Figure 4 shown. Next, the establishment processes of the femoral coordinate system and the tibial coordinate system will be introduced respectively.

[0029] The establishment of the femoral coordinate system can be completed through the following steps 1.1 - 1.4: 1.1 Calculate the midpoint of the line connecting the medial epicondyle point and the lateral epicondyle point and set it as , set the center point of the femoral head as F, and obtain the Y-axis vector of the femoral coordinate system and set it as ; 1.2 Establish a point-normal plane with point and vector ; 1.3 Set the projection point of the medial point of the posterior condyle of the femur on the plane as , set the projection point of the lateral point of the posterior condyle of the femur on the plane as Obtain the X-axis vector of the femoral coordinate system, denoted as . It should be noted that if the operative side is the right side, the direction of the above X-axis vector is reversed; 1.4 Using the above vector to cross-multiply with the vector to obtain the Z-axis vector of the femoral coordinate system , thus completing the construction of the femoral coordinate system.

[0030] The establishment of the tibial coordinate system can be completed through the following steps 2.1 - 2.4: 2.1 Let the center point of the PCL insertion point be , and the tibial tubercle point be , to obtain the vector ; 2.2 Calculate the midpoint of the line connecting the lateral tibial condyle point and the medial tibial condyle point, denoted as , and the center point of the tibial plateau be , to obtain the Y-axis vector of the tibial coordinate system, denoted as ; 2.3 Using the above vector to cross-multiply with the vector to obtain the X-axis vector of the tibial coordinate system ; 2.4 Using the above vector to cross-multiply with the vector to obtain the Z-axis vector of the tibial coordinate system , thus completing the construction of the tibial coordinate system.

[0031] S1022. Determine the initial position of the prosthesis in the pre-constructed three-dimensional model according to the coordinate system.

[0032] In the embodiments of the present application, the initial positions of the femoral prosthesis and the tibial prosthesis can be determined respectively. Specifically, the computer device can first determine the origin of the prosthesis. Among them, for the femoral prosthesis, its origin of the prosthesis can be the distal point of the operative-side femur; for the tibial prosthesis, its origin of the prosthesis can be the operative-side point of the tibial plateau.

[0033] It should be noted that during the operation, the operative side can be divided into the medial or lateral side, or it can also be divided into the left or right side. Therefore, the distal point of the operative-side femur as the origin of the femoral prosthesis can be determined as the medial distal point of the femur or the lateral distal point of the femur according to the actual situation; correspondingly, the operative-side point of the tibial plateau as the origin of the tibial prosthesis can be determined as the medial point of the tibial plateau or the lateral point of the tibial plateau according to the actual situation.

[0034] Then, the computer device can establish a first rotation matrix based on the distal femoral point on the operative side and the femoral coordinate system and determine the initial position of the femoral prosthesis in the three-dimensional model according to the first rotation matrix . The initial position of the femoral prosthesis in the three-dimensional model can be represented by a femoral prosthesis pose matrix, and this pose matrix is:

[0035] The above-mentioned initial position of the femoral prosthesis represented by the femoral prosthesis pose matrix may mean that the computer device can place the femoral prosthesis at a certain position in the three-dimensional model so that the femoral prosthesis can have the pose represented by the above pose matrix. In this way, the current placement position of the femoral prosthesis is also the initial position of the femoral prosthesis.

[0036] On the other hand, the computer device can establish a second rotation matrix based on the tibial plateau point on the operative side and the tibial coordinate system and determine the initial position of the tibial prosthesis in the three-dimensional model according to the second rotation matrix . Similar to the placement position of the femoral prosthesis, the initial position of the tibial prosthesis in the three-dimensional model can be represented by a tibial prosthesis pose matrix, and this pose matrix is:

[0037] The above-mentioned initial position of the tibial prosthesis represented by the tibial prosthesis pose matrix may mean that the computer device can place the tibial prosthesis at a certain position in the three-dimensional model so that the tibial prosthesis can have the pose represented by the above pose matrix. In this way, the current placement position of the tibial prosthesis is also the initial position of the tibial prosthesis.

[0038] S1023. After placing the prosthesis at the initial position, move the prosthesis according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model.

[0039] In the embodiment of the present application, after placing the femoral prosthesis and the tibial prosthesis at the initial positions respectively, the computer device can move the femoral prosthesis and the tibial prosthesis according to the osteotomy amount respectively, so that the planning process can fully consider the osteotomy amount of the prosthesis. The placement positions determined after moving the femoral prosthesis and the tibial prosthesis according to the osteotomy amount are also the actual implantation positions of the femoral prosthesis and the tibial prosthesis planned in the intraoperative stage.

[0040] In a possible implementation manner of the embodiment of the present application, as Figure 5As shown, in S1023, the prosthesis is moved according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model, which specifically may include the following steps S1231 - S1233. Among them, S1231 - S1232 introduce the specific process of moving the femoral prosthesis, and S1233 introduces the specific process of moving the tibial prosthesis.

[0041] S1231. For the femoral prosthesis, displace the femoral prosthesis along the normal vector direction of the distal cross-section of the prosthesis so that the distance from the distal point of the operative-side femur to the distal cross-section of the prosthesis is equal to the distal osteotomy amount of the femoral prosthesis.

[0042] Specifically, for the femoral prosthesis, the computer device can first perform displacement on the distal cross-section of the femoral prosthesis so that the distance from the distal point of the operative-side femur of the moved prosthesis to the distal cross-section of the prosthesis is equal to the distal osteotomy amount of the femoral prosthesis. Depending on whether the operative side is the medial or lateral side, the above-mentioned distal point of the operative-side femur can be the lateral distal point of the femur or the medial distal point of the femur. For example, when the operative side is the medial side, the distal point of the operative-side femur is the medial distal point of the femur; when the operative side is the lateral side, the distal point of the operative-side femur is the lateral distal point of the femur.

[0043] S1232. Displace the femoral prosthesis along the first normal vector direction so that the distance from the operative-side posterior condyle point to the posterior condyle cross-section of the prosthesis is equal to the posterior condyle osteotomy amount of the femoral prosthesis; wherein, the first normal vector is obtained by cross-multiplying the normal vector of the distal cross-section of the prosthesis by the second normal vector, and the second normal vector is obtained by cross-multiplying the normal vector of the posterior condyle cross-section of the prosthesis by the normal vector of the posterior oblique cross-section of the prosthesis.

[0044] Specifically, the computer device can determine the second normal vector obtained by cross-multiplying the normal vector of the posterior condyle cross-section of the femoral prosthesis by the normal vector of the posterior oblique cross-section of the prosthesis . Then, the cross-multiplication result of the normal vector of the distal cross-section of the prosthesis and the second normal vector can be calculated to obtain the first normal vector . The computer device displaces the femoral prosthesis along the direction of the first normal vector so that the distance from the operative-side posterior condyle point to the posterior condyle cross-section of the prosthesis is equal to the posterior condyle osteotomy amount of the femoral prosthesis.

[0045] It should be noted that data such as the distal osteotomy amount, posterior condyle osteotomy amount of the currently planned femoral prosthesis, and the normal vectors of each cross-section can be obtained from the parameter information of the femoral prosthesis. The above-mentioned distal cross-section of the prosthesis is a cross-section near the distal point of the femoral prosthesis. Depending on the operative side, the above-mentioned distal point of the femoral prosthesis is the medial distal point of the femur or the lateral distal point of the femur. The posterior condyle cross-section of the prosthesis is a cross-section near the posterior condyle point on the femoral prosthesis. Similarly, depending on the operative side, the above-mentioned posterior condyle point is the medial posterior condyle point of the femur or the lateral posterior condyle point of the femur. The cross-section between the distal point and the posterior condyle point is the posterior oblique cross-section of the prosthesis.

[0046] S1233. For the tibial prosthesis, displace the tibial prosthesis in the direction of the normal vector of the cross-section of the tibial prosthesis so that the distance from the non-operative-side tibial plateau point to the cross-section of the tibial prosthesis is equal to the osteotomy amount of the tibial prosthesis.

[0047] For the femoral prosthesis, the computer device can displace the tibial prosthesis in the direction of the normal vector of the cross-section of the tibial prosthesis so that the distance from the non-operative-side tibial plateau point to the cross-section of the displaced tibial prosthesis is equal to the osteotomy amount of the tibial prosthesis. The above non-operative-side tibial plateau point can be a fiducial point on the other side opposite to the operative-side tibial plateau point. For example, when the operative side is the medial side, the operative-side tibial plateau point is the medial point of the tibial plateau, so the non-operative-side tibial plateau point is the lateral point of the tibial plateau; when the operative side is the lateral side, the operative-side tibial plateau point is the lateral point of the tibial plateau, so the non-operative-side tibial plateau point is the medial point of the tibial plateau. Data such as the osteotomy amount of the above tibial prosthesis can be obtained from the parameter information of the tibial prosthesis.

[0048] The distal osteotomy amount, posterior condyle osteotomy amount of the femoral prosthesis, and the osteotomy amount of the tibial prosthesis represent the specific thickness of the osteotomy, that is, when implanting a prosthesis of the corresponding model during the operation, it is the thickness of the bone area that needs to be cut off or removed. By referring to the specific osteotomy amount when planning the implanted prosthesis in the embodiments of the present application, it can be ensured that the thickness of the bone cut off in each direction is the same as the thickness of the implanted prosthesis, thereby improving the accuracy of the operation.

[0049] After displacing the femoral prosthesis and the tibial prosthesis respectively according to the above steps, the current positions of the femoral prosthesis and the tibial prosthesis are their final placement positions. As Figure 6 shown, they are respectively examples of a femoral prosthesis and a tibial prosthesis provided by the embodiments of the present application. Among them, Figure 6 part (a) shows a schematic diagram of the femoral prosthesis 610, Figure 6 and part (b) shows a schematic diagram of the tibial prosthesis 620. Based on the femoral prosthesis and the tibial prosthesis shown in Figure 6 , referring to Figure 7 , they are respectively schematic diagrams of the prosthesis placement positions provided by the embodiments of the present application. Among them, Figure 7 part (a) shows the placement position of the femoral prosthesis, that is, the schematic diagram of placing the femoral prosthesis 610 shown in part (a) of Figure 6 in the femoral three-dimensional model. Figure 7 Part (b) shows the placement position of the tibial prosthesis, that is, the schematic diagram of placing the tibial prosthesis 620 shown in part (b) of Figure 6 in the tibial three-dimensional model. In Figure 7In part (a) thereof, the points marked as 711 and 712 are the medial epicondyle point and the lateral epicondyle point among the femoral landmark points, the points marked as 713 and 714 are the medial distal femoral point or the lateral distal femoral point, and the points marked as 715 and 716 are the medial posterior condyle point of the femur or the lateral posterior condyle point of the femur. In Figure 7 In part (b) thereof, the point marked as 721 is the medial tibial plateau point among the tibial landmark points, and the point marked as 722 is the central tibial plateau point.

[0050] S103. Calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position.

[0051] In the embodiment of the present application, the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model can be used for the proportion of the intersection plane of the prosthesis cross-section and the bone cross-section in the bone cross-section. Specifically, since the placement position of the prosthesis determined in the foregoing steps is the position where the prosthesis of this model needs to be implanted during the operation, that is, during the surgical process, the prosthesis needs to be placed at the determined placement position. Therefore, in the preoperative planning stage, it can be determined that when the prosthesis is simulated to be placed at this position, the relatively overlapping area between the prosthesis cross-section and the corresponding bone interface, and this area is the intersection plane of the two. The computer device can calculate the area of the intersection plane and compare it with the area of the corresponding bone cross-section, and the ratio of the two is the coverage rate of the prosthesis cross-section and the corresponding bone cross-section. This coverage rate should be a value less than or equal to 100%. Considering the surgical accuracy and safety, the larger the coverage rate, the better. When the coverage rate is larger, it means that the prosthesis used is more matched with the surgical site of the patient's knee joint.

[0052] In the embodiment of the present application, since the cross-sections of the femoral prosthesis and the tibial prosthesis are different, when calculating the coverage rate of the prosthesis cross-section, it can be carried out separately for the femoral prosthesis and the tibial prosthesis.

[0053] Specifically, for the femoral prosthesis, since its prosthesis cross-section includes the distal prosthesis cross-section, the posterior condyle prosthesis cross-section and the posterior oblique prosthesis cross-section, the corresponding bone cross-sections of these cross-sections in the three-dimensional model correspondingly include the distal femoral cross-section, the posterior condyle femoral cross-section and the posterior oblique femoral cross-section. Therefore, the computer device can first calculate the first areas of the distal prosthesis cross-section, the posterior condyle prosthesis cross-section and the posterior oblique prosthesis cross-section relative to the corresponding distal femoral cross-section, posterior condyle femoral cross-section and posterior oblique femoral cross-section in the three-dimensional model. This first area is also the sum of the areas of the intersection planes formed by the above three prosthesis cross-sections and the corresponding bone cross-sections being relatively or overlapping. The computer device can also calculate the second areas of the distal femoral cross-section, the posterior condyle femoral cross-section and the posterior oblique femoral cross-section. This second area is also the sum of the areas of the above three bone cross-sections. By calculating the ratio of the above first area to the second area, the coverage rate of the femoral prosthesis can be obtained.

[0054] For a tibial prosthesis, the third area of the tibial prosthesis cross-section relative to the corresponding tibial cross-section in the three-dimensional model can be calculated. This third area is also the area of the intersection plane formed by the tibial prosthesis cross-section relative to or coinciding with the corresponding tibial bone cross-section. After the computer device calculates the fourth area of the tibial bone cross-section, the coverage rate of the tibial prosthesis can be obtained by calculating the ratio of the third area to the fourth area.

[0055] In this way, the evaluation process of a certain model of femoral prosthesis and tibial prosthesis is completed, and the coverage rates of the femoral prosthesis and tibial prosthesis are obtained.

[0056] S104. Determine a target prosthesis from the multiple prostheses to be planned according to the coverage rate, and perform preoperative planning for unicompartmental surgery based on the target prosthesis.

[0057] In the embodiment of the present application, the steps S101 - S103 described above introduce the process of evaluating a certain model of prosthesis to be planned, and the obtained evaluation results include the data of the coverage rate of this model of prosthesis. The computer device can evaluate multiple prostheses to be planned in the same way, obtain the coverage rate of each model of prosthesis, and determine the target prosthesis according to the coverage rate. This target prosthesis is the prosthesis that can be used for actual surgery.

[0058] In a possible implementation manner of the embodiment of the present application, a threshold can be set. After the coverage rate data is obtained by evaluating the prosthesis according to the foregoing steps, if the coverage rate is greater than the set threshold, the computer device can use it as the target prosthesis and perform subsequent preoperative planning.

[0059] In another possible implementation manner of the embodiment of the present application, the computer device can also determine the prosthesis with the largest coverage rate from multiple prostheses to be planned as the target prosthesis and perform subsequent preoperative planning. The above target prosthesis includes a femoral target prosthesis and a tibial target prosthesis. In this way, according to the actual situation of the patient, the prosthesis most suitable for the patient can be determined from a variety of optional prostheses and used for preoperative planning, further improving the accuracy of preoperative planning.

[0060] In the embodiment of the present application, when the target prosthesis is determined, the process of the computer device using the target prosthesis for preoperative planning can refer to the process of planning how to guide the doctor to implant the target prosthesis into the corresponding position during the operation. In one example, the planning result can include determining the initial position of the target prosthesis and how to displace the target prosthesis so as to place the target prosthesis at the finally determined placement position. For the determined target prosthesis, the process of determining its placement position described in the foregoing S101 - S102 is also part of the specific process of preoperative planning.

[0061] In the embodiments of the present application, by obtaining parameter information of a prosthesis to be planned including the osteotomy amount, a computer device can determine the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information of the prosthesis. In this way, the computer device can calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section when the prosthesis is placed at the above placement position, and thus can determine a target prosthesis adapted to the patient according to the coverage rate. The computer device can perform preoperative planning for unicompartmental surgery based on the target prosthesis to obtain an optimal surgical plan. In the embodiments of the present application, by automatically setting the initial position of the prosthesis and adjusting the pose of the prosthesis based on parameters such as the osteotomy amount, the shape of the prosthesis to be implanted and the osteotomy amount can be fully considered in the preoperative planning stage, so as to determine the optimal prosthesis model, improve the speed and accuracy of prosthesis planning for unicompartmental surgery, and improve the safety of the surgery.

[0062] It should be noted that the magnitudes of the sequence numbers of the above steps in the embodiments do not mean the order of execution. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0063] For ease of understanding, a complete example is given below to introduce the unicompartmental surgery prosthesis planning method provided by the embodiments of the present application.

[0064] As Figure 8 shown, it is a schematic diagram of a unicompartmental surgery prosthesis planning process provided by the embodiments of the present application. According to the Figure 8 shown process, the entire planning process mainly includes the following steps S801 - S806: S801. Obtain medical images and segment the femur and tibia.

[0065] In this step, an imaging device can be used to scan the patient's knee joint to obtain medical images of the knee joint, and a segmentation algorithm can be used to segment the femur and tibia.

[0066] S802. Based on three-dimensional reconstruction, establish femur and tibia models.

[0067] In this step, a three-dimensional reconstruction method can be used to establish a femur three-dimensional model and a tibia three-dimensional model respectively.

[0068] S803. Mark the femur landmark points and tibia landmark points.

[0069] In this step, a doctor can manually mark the femur landmark points and tibia landmark points in the reconstructed three-dimensional model.

[0070] Among them, the femur landmark points can include Figure 3The center point of the femoral head, the lateral epicondyle point, the medial epicondyle point, the lateral point of the distal femur, the medial point of the distal femur, the lateral point of the posterior femoral condyle, the medial point of the posterior femoral condyle, the center point of the distal femur, etc. shown in the figure; the tibial landmark points may include Figure 4 the lateral tibial condyle point, the medial tibial condyle point, the center point of the tibial plateau, the tibial tuberosity point, the center point of the PCL insertion, the lateral point of the tibial plateau, the medial point of the tibial plateau, etc. shown in the figure.

[0071] S804. Establish a femoral coordinate system and a tibial coordinate system based on the landmark points respectively.

[0072] In this step, the process of establishing the femoral coordinate system can be as follows: A.1) Calculate the midpoint of the line connecting the medial epicondyle point and the lateral epicondyle point and set it as , set the center point of the femoral head as F, and obtain the Y-axis vector of the femoral coordinate system and set it as ; A.2) Establish a point-normal form plane with the point and the vector ; A.3) Let the projection point of the medial point of the posterior femoral condyle on the plane be , let the projection point of the lateral point of the posterior femoral condyle on the plane be , and obtain the X-axis vector of the femoral coordinate system and set it as . It should be noted that if the operative side is the right side, the direction of the above X-axis vector is reversed; A.4) Cross-multiply the above vector by the vector to obtain the Z-axis vector of the femoral coordinate system, and complete the construction of the femoral coordinate system.

[0073] The process of establishing the tibial coordinate system can be as follows: B.1) Let the center point of the PCL insertion be , and the tibial tuberosity point be , to obtain the vector ; B.2) Calculate the midpoint of the line connecting the lateral tibial condyle point and the medial tibial condyle point and set it as , and the center point of the tibial plateau be , to obtain the Y-axis vector of the tibial coordinate system and set it as ; B.3) Cross-multiply the above vector by the vector to obtain the X-axis vector of the tibial coordinate system; B.4) Cross-multiply the above vector by the vector Obtain the Z-axis vector of the tibial coordinate system , and complete the construction of the tibial coordinate system.

[0074] S805. Combine parameter information such as the prosthesis osteotomy amount, and place the femoral prosthesis and the tibial prosthesis at the corresponding positions.

[0075] In this step, based on the selected boundary points, the constructed coordinate system, and the prosthesis parameter information including the osteotomy amount, the placement position of the prosthesis can be determined, and the prosthesis is placed at this position. Among them: The process of placing the femoral prosthesis can be as follows: C.1) Set the origin of the prosthesis as the distal femoral point of the surgical side, and establish a rotation matrix with the X, Y, and Z axes of the femoral coordinate system, that is, the first rotation matrix in the foregoing embodiment. Let the pose matrix of the femoral prosthesis be

[0076] and place the femoral prosthesis at the initial position corresponding to this pose matrix.

[0077] C.2) Displace the femoral prosthesis along the normal vector direction of the distal cross-section of the prosthesis so that the distance from the distal femoral point of the surgical side to the distal cross-section of the prosthesis is equal to the distal osteotomy amount of the femoral prosthesis.

[0078] C.3) Calculate the cross product result of the normal vector of the posterior condyle cross-section of the femoral prosthesis and the normal vector of the posterior inclined cross-section of the prosthesis to obtain the vector , that is, the second normal vector in the foregoing embodiment. Then cross-multiply the normal vector of the distal cross-section of the prosthesis by the second normal vector to obtain the vector , that is, the first normal vector in the foregoing embodiment.

[0079] C.4) Displace the femoral prosthesis on the first normal vector so that the distance from the posterior condyle point of the surgical side to the posterior condyle cross-section of the prosthesis is equal to the posterior condyle osteotomy amount of the femoral prosthesis. Thus, the placement position of the femoral prosthesis is planned.

[0080] The process of placing the tibial prosthesis can be as follows: D.1) Set the origin of the tibial prosthesis as the tibial plateau point of the surgical side, and establish a rotation matrix with the X, Y, and Z axes of the tibial coordinate system, that is, the second rotation matrix in the foregoing embodiment. Let the pose matrix of the tibial prosthesis be

[0081] And place the tibial prosthesis at the initial position corresponding to this pose matrix.

[0082] D.2) Displace the tibial prosthesis in the direction of the normal vector of the tibial prosthesis cross-section so that the distance from the non-operative-side tibial plateau point to the tibial prosthesis cross-section is equal to the osteotomy amount of the tibial prosthesis. Thus, the placement position of the tibial prosthesis is planned.

[0083] S806. Based on the current placement position, plan and select the femoral prosthesis and tibial prosthesis with the largest coverage rate, and complete the surgical plan.

[0084] In this step, the computer device can traverse and place all prostheses, and plan and obtain the optimal femoral prosthesis and tibial prosthesis. Specifically, this step includes femoral prosthesis planning and tibial prosthesis planning. Among them: The femoral prosthesis planning process can be: E.1) Traverse all femoral prostheses, determine the placement position of each femoral prosthesis according to the foregoing steps, and place the femoral prosthesis at this position.

[0085] E.2) Sequentially determine the distal prosthesis cross-section, the posterior condyle prosthesis cross-section, and the posterior oblique prosthesis cross-section, as well as the distal femoral cross-section, the posterior condyle femoral cross-section, and the posterior oblique femoral cross-section in the three-dimensional model.

[0086] E.3) Based on the femoral prosthesis cross-section and the corresponding femoral cross-section in the three-dimensional model, calculate the area of the intersection plane of the pairwise corresponding cross-sections. That is, the area of the intersection plane where the distal prosthesis cross-section is opposite or coincides with the corresponding distal femoral cross-section, the area of the intersection plane where the posterior condyle prosthesis cross-section is opposite or coincides with the corresponding posterior condyle femoral cross-section, and the area of the intersection plane where the posterior oblique prosthesis cross-section is opposite or coincides with the corresponding posterior oblique femoral cross-section.

[0087] E.4) Based on the sum of the areas of all intersection planes (the first area in the foregoing embodiment), calculate the ratio of the sum of the areas of all intersection planes to the sum of the areas of all femoral cross-sections (the second area in the foregoing embodiment). This ratio is the coverage rate of the femoral prosthesis.

[0088] E.5) Select the femoral prosthesis with the largest coverage rate for preoperative planning.

[0089] The tibial prosthesis planning process can be: F.1) Traverse all tibial prostheses, determine the placement position of each tibial prosthesis according to the foregoing steps, and place the tibial prosthesis at this position.

[0090] F.2) Determine the tibial prosthesis cross-section and the corresponding tibial cross-section in the three-dimensional model, and calculate the area of the intersection plane where they are opposite or coincide (the third area in the foregoing embodiment).

[0091] F.3) Calculate the ratio of the intersection plane to the tibial cross-section in the three-dimensional model (the area of the tibial cross-section is the fourth area in the foregoing embodiments) based on the area of the intersection plane, and this ratio is the coverage rate of the tibial prosthesis.

[0092] F.4) Select the tibial prosthesis with the largest coverage rate for preoperative planning.

[0093] By applying the unicompartmental surgery prosthesis planning method provided in the embodiments of the present application, the pose of the prosthesis can be automatically set based on the selected fiducial points and the osteotomy amount of the prosthesis. Through the calculation of the coverage rate of the prosthesis cross-section, the optimal prosthesis model is planned and selected, making the unicompartmental prosthesis planning faster, more accurate, and safer.

[0094] Refer to Figure 9 , which shows a schematic diagram of a unicompartmental surgery prosthesis planning device provided in the embodiments of the present application. Specifically, it may include a parameter information acquisition module 901, a placement position determination module 902, a coverage rate calculation module 903, and a preoperative scale module 904, where: The parameter information acquisition module 901 is used to acquire the parameter information of the prosthesis to be planned. The prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount; The placement position determination module 902 is used to determine the placement position of the prosthesis in the pre-constructed three-dimensional model according to the parameter information; The coverage rate calculation module 903 is used to calculate the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position. The coverage rate represents the proportion of the intersection plane between the prosthesis cross-section and the bone cross-section in the bone cross-section; The preoperative scale module 904 is used to determine the target prosthesis from multiple prostheses to be planned according to the coverage rate, and perform preoperative planning for unicompartmental surgery based on the target prosthesis.

[0095] In the embodiments of the present application, the placement position determination module 902 may specifically be used for: Establish a coordinate system based on the selected fiducial points; Determine the initial position of the prosthesis in the pre-constructed three-dimensional model according to the coordinate system; After placing the prosthesis at the initial position, move the prosthesis according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model.

[0096] In the embodiments of the present application, the coordinate system may include a femoral coordinate system and a tibial coordinate system, and the placement position determination module 902 may also be used for: Determine the prosthesis origin; wherein, the prosthesis origin of the femoral prosthesis is the distal point of the operative-side femur, and the prosthesis origin of the tibial prosthesis is the operative-side point of the tibial plateau; Based on the distal point of the operative-side femur and the femoral coordinate system, establish a first rotation matrix, and determine the initial position of the femoral prosthesis in the three-dimensional model according to the first rotation matrix; and, Based on the operative-side point of the tibial plateau and the tibial coordinate system, establish a second rotation matrix, and determine the initial position of the tibial prosthesis in the three-dimensional model according to the second rotation matrix.

[0097] In a possible implementation manner of the embodiment of the present application, the placement position determination module 902 may further be used for: For the femoral prosthesis, displace the femoral prosthesis along the normal vector direction of the distal prosthesis cross-section, so that the distance from the distal point of the operative-side femur to the distal prosthesis cross-section is equal to the distal osteotomy amount of the femoral prosthesis; Displace the femoral prosthesis along the first normal vector direction, so that the distance from the posterior condyle point of the operative-side to the posterior condyle cross-section of the prosthesis is equal to the posterior condyle osteotomy amount of the femoral prosthesis; wherein, the first normal vector is obtained by cross-multiplying the normal vector of the distal prosthesis cross-section by the second normal vector, and the second normal vector is obtained by cross-multiplying the normal vector of the posterior condyle cross-section of the prosthesis by the normal vector of the posterior oblique cross-section of the prosthesis.

[0098] In another possible implementation manner of the embodiment of the present application, the placement position determination module 902 may further be used for: For the tibial prosthesis, displace the tibial prosthesis along the normal vector direction of the tibial prosthesis cross-section, so that the distance from the non-operative-side tibial plateau point to the tibial prosthesis cross-section is equal to the osteotomy amount of the tibial prosthesis.

[0099] In the embodiment of the present application, the coverage rate calculation module 903 may specifically be used for: For the femoral prosthesis, calculate the first area of the distal prosthesis cross-section, the posterior condyle cross-section of the prosthesis, and the posterior oblique cross-section of the prosthesis relative to the corresponding distal cross-section of the femur, the posterior condyle cross-section of the femur, and the posterior oblique cross-section of the femur in the three-dimensional model; and the second area of the distal cross-section of the femur, the posterior condyle cross-section of the femur, and the posterior oblique cross-section of the femur; calculate the ratio of the first area to the second area to obtain the coverage rate of the femoral prosthesis; For the tibial prosthesis, calculate the third area of the tibial prosthesis cross-section relative to the corresponding tibial cross-section in the three-dimensional model; and the fourth area of the tibial cross-section; calculate the ratio of the third area to the fourth area to obtain the coverage rate of the tibial prosthesis.

[0100] In the embodiment of the present application, the preoperative scale module 904 may specifically be used for: Determine the prosthesis with the largest coverage rate among multiple prostheses to be planned as the target prosthesis; the target prosthesis includes a femoral target prosthesis and a tibial target prosthesis.

[0101] A unicompartmental surgery prosthesis planning device provided by an embodiment of the present application may be a computer device or a functional module in a computer device that can implement the steps in each of the foregoing method embodiments. By applying this device, each step in each of the foregoing method embodiments can be implemented.

[0102] For the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For related parts, refer to the description in the method embodiment section.

[0103] Refer to Figure 10 , which shows a schematic diagram of a computer device provided by an embodiment of the present application. As Figure 10 shown, the computer device 1000 in the embodiment of the present application includes: a processor 1010, a memory 1020, and a computer program 1021 stored in the memory 1020 and executable on the processor 1010. When the processor 1010 executes the computer program 1021, the steps in each of the foregoing embodiments of the unicompartmental surgery prosthesis planning method are implemented, such as Figure 1 the steps S101 to S104 shown. Alternatively, when the processor 1010 executes the computer program 1021, the functions of each module / unit in each of the foregoing device embodiments are implemented, such as Figure 9 the functions of the modules 901 to 904 shown.

[0104] Exemplarily, the computer program 1021 may be divided into one or more modules / units. The one or more modules / units are stored in the memory 1020 and executed by the processor 1010 to complete the present application. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and these instruction segments may be used to describe the execution process of the computer program 1021 in the computer device 1000. For example, the computer program 1021 may be divided into a parameter information acquisition module, a placement position determination module, a coverage rate calculation module, and a preoperative scale module. The specific functions of each module are as follows: The parameter information acquisition module is used to acquire the parameter information of the prosthesis to be planned. The prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount; The placement position determination module is used to determine the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information; A coverage calculation module, configured to calculate a coverage rate between a prosthesis cross-section and a corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position, where the coverage rate represents the proportion of the intersection plane of the prosthesis cross-section and the bone cross-section in the bone cross-section; A preoperative sizing module, configured to determine a target prosthesis from multiple prostheses to be planned according to the coverage rate, and perform preoperative planning for unicompartmental surgery based on the target prosthesis.

[0105] The computer device 1000 may be a device capable of performing each step in the foregoing method embodiments. The computer device 1000 may be a desktop computer, a cloud server, or the like. For example, the computer device 1000 may be a computer-aided medical device. The computer device 1000 may include, but is not limited to, a processor 1010 and a memory 1020. Those skilled in the art can understand that Figure 10 This is only an example of the computer device 1000 and does not constitute a limitation on the computer device 1000. It may include more or fewer components than shown in the figure, or combine some components, or different components. For example, the computer device 1000 may further include input / output devices, network access devices, a bus, etc.

[0106] The processor 1010 may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0107] The memory 1020 may be an internal storage unit of the computer device 1000, such as the hard disk or memory of the computer device 1000. The memory 1020 may also be an external storage device of the computer device 1000, such as a plug-in hard disk equipped on the computer device 1000, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. Further, the memory 1020 may also include both the internal storage unit and the external storage device of the computer device 1000. The memory 1020 is used to store the computer program 1021 and other programs and data required by the computer device 1000. The memory 1020 may also be used to temporarily store the data that has been output or will be output.

[0108] An embodiment of the present application also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the methods described in the foregoing embodiments are implemented.

[0109] An embodiment of the present application also discloses a computer-readable storage medium storing a computer program, and when the computer program is executed by a computer, the methods described in the foregoing embodiments are implemented.

[0110] An embodiment of the present application also discloses a computer program product including a computer program, and when the computer program runs on a computer, the computer is caused to execute the methods described in the foregoing embodiments.

[0111] The above-described embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for planning a unicondylar surgical prosthesis, characterized in that, Including: Obtaining parameter information of a prosthesis to be planned, where the prosthesis includes a femoral prosthesis and a tibial prosthesis, and the parameter information includes the osteotomy amount; Determining the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information; Calculating the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position, where the coverage rate represents the proportion of the intersection plane of the prosthesis cross-section and the bone cross-section in the bone cross-section; Determining a target prosthesis from multiple prostheses to be planned according to the coverage rate, and performing preoperative planning for unicompartmental surgery based on the target prosthesis.

2. The method according to claim 1, characterized in that, The determining the placement position of the prosthesis in the pre-constructed three-dimensional model according to the parameter information includes: Establishing a coordinate system based on selected fiducial points; Determining the initial position of the prosthesis in the pre-constructed three-dimensional model according to the coordinate system; After placing the prosthesis at the initial position, moving the prosthesis according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model.

3. The method according to claim 2, wherein The coordinate system includes a femoral coordinate system and a tibial coordinate system. The determining the initial position of the prosthesis in the pre-constructed three-dimensional model according to the coordinate system includes: Determining the prosthesis origin; where the prosthesis origin of the femoral prosthesis is the distal point of the operative-side femur, and the prosthesis origin of the tibial prosthesis is the operative-side point of the tibial plateau; Establishing a first rotation matrix based on the distal point of the operative-side femur and the femoral coordinate system, and determining the initial position of the femoral prosthesis in the three-dimensional model according to the first rotation matrix; and, Establishing a second rotation matrix based on the operative-side point of the tibial plateau and the tibial coordinate system, and determining the initial position of the tibial prosthesis in the three-dimensional model according to the second rotation matrix.

4. The method according to claim 2, wherein The moving the prosthesis according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model includes: For the femoral prosthesis, displacing the femoral prosthesis along the normal vector direction of the distal cross-section of the prosthesis so that the distance from the distal point of the operative-side femur to the distal cross-section of the prosthesis is equal to the distal osteotomy amount of the femoral prosthesis; Displacing the femoral prosthesis along the first normal vector direction so that the distance from the posterior condyle point of the operative-side to the posterior condyle cross-section of the prosthesis is equal to the posterior condyle osteotomy amount of the femoral prosthesis; where the first normal vector is obtained by cross-multiplying the normal vector of the distal cross-section of the prosthesis by the second normal vector, and the second normal vector is obtained by cross-multiplying the normal vector of the posterior condyle cross-section of the prosthesis by the normal vector of the posterior oblique cross-section of the prosthesis.

5. The method according to claim 2, characterized in that, The moving the prosthesis according to the osteotomy amount in the parameter information to obtain the placement position of the prosthesis in the three-dimensional model includes: For the tibial prosthesis, displacing the tibial prosthesis along the normal vector direction of the cross-section of the tibial prosthesis so that the distance from the non-operative-side point of the tibial plateau to the cross-section of the tibial prosthesis is equal to the osteotomy amount of the tibial prosthesis.

6. The method according to any one of claims 1 to 5, characterized in that The calculating the coverage rate between the prosthesis cross-section and the corresponding bone cross-section in the three-dimensional model when the prosthesis is in the placement position includes: For the femoral prosthesis, calculate the first area of the distal prosthesis section, the posterior condyle prosthesis section, and the posterior oblique prosthesis section relative to the corresponding distal femoral section, posterior femoral condyle section, and posterior oblique femoral section in the three-dimensional model; and the second area of the distal femoral section, the posterior femoral condyle section, and the posterior oblique femoral section; calculate the ratio of the first area to the second area to obtain the coverage rate of the femoral prosthesis. For the tibial prosthesis, calculate the third area of the tibial prosthesis section relative to the corresponding tibial section in the three-dimensional model; and the fourth area of the tibial section; calculate the ratio of the third area to the fourth area to obtain the coverage rate of the tibial prosthesis.

7. The method according to claim 6, wherein Determining a target prosthesis from a plurality of prostheses to be planned according to the coverage rate includes: Determining the prosthesis with the largest coverage rate from a plurality of prostheses to be planned as the target prosthesis; the target prosthesis includes a femoral target prosthesis and a tibial target prosthesis.

8. A unicompartmental surgical prosthesis planning device, characterized in that, Includes: A parameter information acquisition module for acquiring parameter information of the prosthesis to be planned, the prosthesis including a femoral prosthesis and a tibial prosthesis, and the parameter information including the osteotomy amount. A placement position determination module for determining the placement position of the prosthesis in a pre-constructed three-dimensional model according to the parameter information. A coverage rate calculation module for calculating the coverage rate between the prosthesis section and the corresponding bone section in the three-dimensional model when the prosthesis is in the placement position, where the coverage rate represents the proportion of the intersection plane of the prosthesis section and the bone section in the bone section. A preoperative planning module for determining a target prosthesis from a plurality of prostheses to be planned according to the coverage rate and performing preoperative planning for unicompartmental surgery based on the target prosthesis.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, the computer device implements the method according to any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program runs, the method according to any one of claims 1 to 7 is executed.

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