Implant assistance method and implant assistance system for optimised insertion or joint replacement

Abstract

The disclosure relates to a computer-implemented implant assistance method for simulating and selecting at least one implant for optimised insertion or joint replacement during a surgical procedure on a patient (P), comprising the steps of: reading in (S1) at least one implant parameter, in particular at least one implant dimension and / or a weight restriction, of a selected implant model (6'); calculating (S2), by means of a calculation unit and on the basis of the at least one read-in implant parameter, simulated loads due to predefined forces and moments at and on the implant model (6'); determining (S3), by means of the calculation unit and on the basis of the at least one read-in implant parameter, whether load limits of the implant model (6') are adhered to in the simulated loads; and, by means of a display device, outputting a visual confirmation of a selection of the implant model if the load limits are adhered to or outputting a visual warning before the selection of the implant model if the load limits are exceeded. In addition, the disclosure relates to an implant assistance system and to a computer-readable storage medium according to the additional independent claims.

Description

[0001]AE2030P-WO-0016 2021P00201 WO 1 / 21 Implant assistance method and implant assistance system for optimized use or joint replacement Description Technical field The present disclosure relates to an implant assistance method for optimized use of an implant or (partial or complete) joint replacement by means of an implant during a surgical procedure on a patient. In addition, the disclosure relates to an implant assistance system and a computer-readable storage medium according to the preambles of the independent claims. Background of the disclosure Preoperative planning of interventions, which may be (re-)adjusted intraoperatively, is currently usually based solely on the anatomical conditions or the anatomy of the patient on the one hand and implant dimensions on the other. In this case, the patient's weight restrictions defined by the manufacturer for specialImplant sizes must be taken into account. However, specifying a weight limit as the sole parameter for selecting the implant is often too one-sided and too imprecise and can lead to the (optimally) suitable implant for the patient not being selected. As a result, the selected implant does not meet the patient's requirements, in particular mechanical requirements, which can lead to serious complications later on. The correct selection of an implant and a prediction of a possible complication is therefore crucial for the successful implantation of the implant, which should effectively and safely fulfill its function over the entire lifetime of the patient. AE2030P-WO-0016 2021P00201 WO 2 / 21 Summary of the Disclosure Therefore, the objects and aims of the present disclosure are to provide an implant assistance method and implant assistance system as well as a computer-readable storage medium forto provide an optimized joint replacement that allows for an even better selection of an implant based on parameters that is optimally adapted to the patient. A further sub-task is to test the implant in advance to determine whether it is suitable for the patient and the application. The objects of the present disclosure are solved according to the invention by the features of claim 1 with regard to a generic implant assistance method, by the features of claim 11 with regard to a generic implant assistance system, and by the features of claim 12 with regard to a computer-readable storage medium. A basic idea of ​​the present disclosure therefore provides that, when selecting an implant, in contrast to the prior art, in which mechanical load limits of the implants are regularly disregarded,In particular, depending on the respective installation situation of the implant, such load limits must be taken into account for the selection. The dynamic forces and moments acting on or at the implant are taken into account over the course of the load profiles (simulated loads), for example in the case of a load profile of the patient walking or running, in particular depending on the patient's weight and the installation situation (i.e. the position and orientation of the implant in the patient's body). These parameters of the load profiles with the (dynamic) forces and moments in a load profile are of crucial importance for successful implantation. In the simplest case, only static forces and moments on the implant can be taken into account. The present disclosure therefore proposes, as part of the pre- or intraoperative planning, a computer-assisted simulation of the loads with the forces AE2030P-WO-0016 2021P00201 WO 3 / 21 and moments on or atthe selected implant or implant model. This takes into account the load limits of the implant component(s) and, in particular, patient-specific parameters. This allows the best possible care for the patient without exceeding the load limits of the implant or implant components (e.g., the implant components in a knee replacement). In particular, the pre- and intraoperative planning of a TKA (Total Knee Arthroplasty) operation is enhanced by a simulation of the forces and moments on the implant. In other words, a computer-implemented implant assistance procedure and an assistance system for simulating and selecting at least one implant for optimized use or joint replacement during a surgical procedure in a patient are proposed. The system comprises the following steps and a correspondingly adapted control unit:Reading in at least one implant parameter, in particular at least one implant dimension and / or a weight limit, of a selected implant model; calculating, by a calculation unit and based on the at least one read-in implant parameter, simulated loads using predefined forces and moments on and acting on the implant model; determining, by the calculation unit and based on the at least one read-in implant parameter, whether the load limits of the implant model are met under the simulated loads; and outputting, by a display device, for example a surgical monitor, a visual confirmation of the selection of the implant model if the load limits are met or outputting a visual warning of the implant model if the load limits are exceeded. In particular, in addition to the visual warning, an acoustic warning signal / alarm can be output via a loudspeaker.The term "implant model" is understood here to mean a computer-readable, digital model of the implant, which replicates the real implant of the real world in the digital world and attempts to approximate it. In particular, the AE2030P-WO-0016 2021P00201 WO 4 / 21 implant model is a three-dimensional CAD model, with which the numerical calculations with regard to a mechanical load are carried out. Advantageous embodiments are claimed in the subclaims and are explained below. According to a preferred embodiment, the step of calculating simulated loads can replicate / simulate a load situation of a dynamic activity, in particular walking or running, on the implant model, in particular a load situation scaled to 100 kg, which was preferably obtained from measurement data of an instrumented knee prosthesis. In other words, in one embodiment, the simulation can be the averaged and100 kg scaled load situation during at least one dynamic activity, which was obtained from measurement data of instrumented knee prostheses. In this way, a subsequent usual movement of the patient can be simulated and the forces and moments caused by the movement on the implant can be simulated (as simulated loads). The assistance method and the assistance system can thus be used to carry out checks as to whether the selected implant and preferably an implant alignment is suitable for these dynamic temporal load profiles with the forces and moments. According to a further preferred embodiment, in the step of calculating simulated loads, a standardized load test according to ISO 14879-1 or ISO 14243 can be used as a basis and simulated and calculated accordingly. Preferably, tests according to at least one standard ISO 14879-1 (Implants for surgery - Total knee-jointprostheses) or ISO 14243 (Implants for surgery — Wear of total knee-joint prostheses) and calculated in the simulated loads. The implant components are simulated. In this way, a standardized simulated load according to a standard is provided in order to obtain a standardized, meaningful and reliable calculation. These simulated loads of the standards cover a common standard range. AE2030P-WO-0016 2021P00201 WO 5 / 21 Preferably, the at least one implant parameter can be an implant type and / or an implant size and / or an implant dimension and / or a position and orientation (location) of the at least one implant. In other words, in particular an implant type, an implant size, a position and / or an orientation of the individual (implant) components of the selected implant can be adopted from the preoperative planning. In particular, the implant assistance methodevaluate a large number of implants or implant components and import a large number of implant parameters for different implants or implant components. Preferably, the patient weight and the installation situation are imported as parameters and used as the basis for the calculation. The simulated loads are therefore additionally adjusted, in particular, based on the actual weight and at least one muscular parameter of the patient. The simulation is thus calculated for each individual patient. In one embodiment, the result is displayed as to whether the determined forces and moments lie within the range of the values ​​previously defined as permissible for the implant. If the values ​​are higher, the desired service life of the implant is unlikely to be achieved, which must be avoided. Thus, for the first time, the loads on the implant system (e.g. anchorage stability) and the expected implant service life (e.g. increasedWear) are included in the preoperative planning. In particular, the simulated load with the forces and moments on the implant model can correlate with the patient weight, i.e. with a higher patient weight, correspondingly higher forces and moments on the implant model are used as a basis. According to one embodiment, the step of calculating simulated loads can include the (actual) weight of the patient and / or a muscular parameter of the patient in order to provide a patient-specific calculation and selection. AE2030P-WO-0016 2021P00201 WO 6 / 21 According to a further embodiment, the method can further comprise the step of: reading in a patient anatomy by reading in three-dimensional images / image data of the patient, in particular MRI images and / or CT images and / or X-ray images, in order to create a simulation model with a patient model and the implant model and the step ofCalculations can be carried out even more precisely, in particular on the basis of a three-dimensional section of a skeleton model and / or a musculoskeletal model of the patient. In other words, an integration of an individual patient anatomy based on recordings / image data is preferably provided. In this case, the simulation model with the implant model is expanded to include a patient model, in particular bony elements for the femur and tibia. This expanded simulation model, with the implant model on the one hand and the patient model on the other, now allows for an even more precise and individually adapted calculation of the simulated loads on the implant model via numerical calculations. Based on X-ray images and / or CT data and / or MRI data, the geometry of the bones in the simulation can preferably be adapted to the patient anatomy. This process can preferably be carried out, especially when using X-ray images, by theThe use of an SSM (Statistical Shape Model) can simplify and improve the simulation process. Here, a statistical 3D model is deformed based on the dimensions from the 2D X-ray image so that it best replicates the patient's bone in 3D. In other words, the dimensional parameters of a three-dimensional "sample model" are adapted and approximated accordingly based on a two-dimensional X-ray image. According to a preferred embodiment, the simulation, i.e. the step of calculating the simulated loads, can be carried out intraoperatively. This makes it possible to integrate intraoperative events and data that can only be collected intraoperatively into the simulation. In particular, a three-dimensional bone geometry can be calculated based on palpated landmarks on the patient, which are recorded in space by the navigation system, preferably using a Statistical Shape Model (SSM), and then used in the simulation.find or be used as a basis. AE2030P-WO-0016 2021P00201 WO 7 / 21 In particular, an intraoperative ligament situation and / or a measured joint gap depending on applied forces and flexion angles can also be taken into account in the simulation or calculation of the simulated loads. Preferably, the assistance method, in the step of issuing the visual warning when the load limits are exceeded, can further comprise the step of issuing, on the basis of a stored implant data set, a (suggestion of an) implant model with a modified implant size and / or implant orientation that complies with the load limits. For example, for a selected implant size of 5, the next larger and suitable implant size of 4 can be suggested and visually output accordingly. In other words, in the case of excessive loads or exceeding the load limits, the simulation result can also contain suggestions as to how thesecan be reduced. This can be achieved, for example, by changing the implant size or implant orientation. A visual output can preferably also be provided on a partial area of ​​the display device, in particular a navigation screen. If, for example, the implant parameters and / or the parameters for positioning and alignment of the implant are changed during intraoperative navigation, a corresponding output can indicate whether the selected parameters or values ​​are still within the load limits or not. This is particularly advantageous if a corresponding simulation becomes part of the navigation application and supports the surgeon accordingly. Preferably, the step of outputting a suggestion of an implant model can comprise the steps of outputting, on a partial area of ​​the display device, in particular the navigation screen, an implant model and a colored (volume))area or corridor for the implant model, with different degrees of compatibility / fit ratings. In particular, a red corridor can be displayed in the navigation data via the navigation screen for the area that was determined by the calculation to be unsuitable for the implant model, a yellow corridor can be displayed for an area of ​​the implant model that was calculated as average for the implant, and a green corridor can be calculated for a (volume) area of ​​the implant model that was determined to be good for the implant model. In this way, a surgeon is given a selection of options for positioning and aligning the implant model in advance. Preferably, an implant size can also be changed and recalculated accordingly and visually displayed in the navigation data. Such a corridor can be used in particular inThe implant can be designed in the form of a virtual volume, which is partially transparent in order to display the surrounding tissue accordingly. The transparency is preferably less than 50%. By coloring the corridor accordingly in red, yellow, and / or green (in one embodiment, the surgeon (user) can toggle through the three corridors red, yellow, and green in order to display the implant model individually), a simple and intuitive representation of a possible positioning and orientation can be provided to the surgeon in order to make planning and implementation even more efficient and to further minimize the procedure time. This can be done both preoperatively and intraoperatively. Using correspondingly calculated volume models, this particularly suitable corridor for an implant model can be calculated, particularly intraoperatively, in a timely manner, precisely for the surrounding tissue or bone.The decision regarding the implant and the parameters is ultimately made by the surgeon, but is accordingly very well supported in advance. According to one embodiment, the method can further comprise the steps of: detecting, in particular before an incision (intra-operatively) or pre-operatively, the kinematics of the patient's joint using a navigation system or a tracking system, in particular by means of markers attached to the joint or inertial measurement units (IMU) attached to the joint; determining, based on the detected kinematics of the patient, a kinematic phenotype; and outputting, based on the phenotype, a suggestion for an implant type and / or an implant orientation. In this embodiment, the patient kinematics of the relevant area are thus detected using a navigation system, in particular intraoperatively, but before the joint incision. For this purpose, in particular, stab incisions are made on the femur and the tibiaMarkers are attached to the patient. Alternatively, the kinematics can be recorded using an IMU attached to the joint. Clinical standard tests, in particular the Lachmann test, are then preferably carried out and recorded. After the markers have been attached, the leg is passively moved several times from extension to flexion and back. Maximum varus stress, maximum valgus stress, or no lateral load is applied to the joint. These maximum values ​​regarding varus and valgus, as well as the natural varus or valgus, without lateral force application, across the entire possible flexion allow a characterization of the soft tissue situation and can then be taken into account in the simulation. In this way, the simulation model is mapped even more accurately with the implant model, and an even better statement can be made regarding the selection of the implant model. Furthermore, an embodimentinclude the preoperative recording of a patient's kinematics, in particular their kinematic phenotype. If the patient's movement data is recorded preoperatively, the kinematic phenotype can be determined from this. According to the literature, there are various phenotypes into which kinematic patterns can be classified. The different phenotypes are taken into account when selecting the implant type and sometimes require different implant orientations. Only in this way can the patient's preoperative, natural kinematics be successfully reproduced postoperatively. For this reason, the patient's kinematic data can also be used in the simulation. The goal of the simulation and calculation of the simulated loads is then to maintain the load limits of the implant over the entire activity profile, under the boundary condition of reconstructing the patient's natural or optimal kinematics. According to a further embodiment,In addition to the at least one implant parameter, a further parameter relating to ground reaction forces and / or electromyography data (EMG data) and / or moving images, in particular from a fluoroscope, is read in in order to simulate a patient kinematics profile and, by inverse kinematics, to obtain a temporal profile of the predefined forces and moments on the implant, which are used as a basis for the calculation step as simulated loads. In the embodiments described above, the simulation is carried out in particular with only skeletal models, i.e. models which do not have muscle forces, tendon attachments, and the like. In this embodiment, however, in addition to the (basic AE2030P-WO-0016 2021P00201 WO 10 / 21) parameters, ground reaction forces, EMG data and / or moving images, e.g. from a fluoroscope, are also used. The data thus added creates, over the entire (temporal) profile of the recordedActivity, a comprehensive picture of the patient's kinematics. Using the inverse kinematics approach, the forces and moments in the joint or on the implant can now be calculated in the simulation and analyzed over time. This can be done particularly accurately if the ligament attachments are previously determined from the 3D image data used to create the 3D bone model and used in a musculoskeletal model. Preferably, the assistance method can further comprise the steps of: Creating a multidimensional matrix based on a variance of input parameters; Determining limits / boundary parameters that must be adhered to in the respective combination of input parameters so that the load limits are met; Preferably, outputting, depending on the patient's weight and implant size, an output parameter, the varus / valgus angle, under which the implant can be inserted without exceeding the load limits.exceed; and preferably issuing a confirmation if a combination of the input parameters lies within the defined limits or issuing a warning if a combination of the input parameters lies outside the defined limits. In order to keep the simulation and calculation time as short as possible, especially intraoperatively, all necessary calculations can be carried out in advance. Based on the variances of the input variables, a multidimensional matrix can be created. In this matrix, the boundary parameters are determined for each input variable, which must be maintained in the respective combination of input variables in order to ensure that the loads remain below the previously defined limits. This results in a maximum varus-valgus angle for each implant size, depending on the patient's weight, at which the prosthesis can be inserted without exceeding the load limits. If allIf these limits are determined for all input parameters, intraoperative simulation and calculation can be omitted. It only needs to be checked whether the respective parameter combination lies within or outside the defined limits. The complexity of this matrix increases with each input parameter, because the dimensions of the matrix correspond to the number of input parameters. Accordingly, there is a degree of complexity at which it is easier to calculate the simulation directly with the corresponding input parameters using a simulation model, such as a numerical simulation of a CAD model. Preferably, the method can comprise a step of creating a multidimensional matrix with: Creating an MxN matrix, where M is the number of input parameters and N is at least three, with an entry for the variance of the input parameter, an entry for the lower limit, and an entry for the upper limit, where the enteredValues ​​of the lower limit and / or the upper limit as well as the variances are, in particular, static values ​​that have already been determined in advance for the specific combination of input parameters in order to enable rapid calculation. In particular, the implant is a knee joint implant, a shoulder implant, a hip implant, a spinal implant, or an ankle implant. Preferably, the implant can also be a vascular implant. The approach of simulating and calculating the loads on the implant or implant model during preoperative planning and taking load limits into account accordingly can be applied in particular to joint implants such as a shoulder implant, hip implant, a spinal implant, and an ankle implant. If sufficient data is available and / or recorded, the design of a vascular implant can also be simulated. Here, the recording and simulation of volume flows, pressures, andViscosity is relevant. Both the dimension and the design of the implant can then be simulated. The present disclosure therefore particularly deals with a patient-specific simulation of implant loads using kinematic phenotypes and a gait analysis (gait analysis), in particular a gait analysis "Smart Gait Lab". AE2030P-WO-0016 2021P00201 WO 12 / 21 The objects of the present disclosure are achieved with regard to an implant assistance system for simulating and selecting at least one implant for optimized use or joint replacement during a surgical procedure on a patient, with a display device, in particular an operating room monitor, for outputting visual content, in that it has: a control unit which is adapted for: at least one implant parameter, in particular at least one implant dimension and / or a weight limit, of a selectedImplant model; based on the at least one read-in implant parameter, to calculate simulated loads using predefined forces and moments on and onto the implant model; based on the at least one read-in implant parameter, to determine whether load limits of the implant model are met under the simulated loads; and output, by the display device, a visual confirmation of a selection of the implant model if the load limits are met or output a visual warning of the implant model if the load limits are exceeded. With regard to a computer-readable storage medium, the objects of the present disclosure are achieved in that it comprises instructions which, when executed by a computer, cause the computer to carry out the assistance method according to the present disclosure. Any disclosure in connection with the assistance method of the present disclosure also applies to theAssistance system of the present disclosure, and vice versa. Brief description of the figures The present disclosure is explained in more detail below with reference to preferred embodiments with the aid of figures. There show: Fig. 1 a schematic view of an implant assistance system according to a preferred embodiment of the present disclosure; and AE2030P-WO-0016 2021P00201 WO 13 / 21 Fig. 2 a flowchart of an implant assistance method according to a preferred embodiment of the present disclosure. The figures are schematic in nature and are intended only to assist in understanding the invention. Identical elements are provided with the same reference numerals. The features of the various embodiments can be interchanged. Detailed description of preferred embodiments Fig. 1 shows a schematic view of an implant assistance system 1 (hereinafter referred to as assistance system) according to a preferred embodiment. TheImplant assistance system 1 of the present embodiment is adapted for simulating and selecting at least one implant 6 for optimized insertion or joint replacement during a surgical procedure on a patient P. Specifically, it comprises a display device 4 in the form of an operating room monitor to output visual content for medical personnel, in particular a surgeon. Furthermore, the assistance system 1 comprises a control unit 2 that is specially adapted to read in at least one implant parameter in the form of an implant dimension and a weight limit of a selected implant model 6'. This implant model 6' is a digital counterpart to a real implant and is intended to provide a computer-readable replica of this implant 6, which is inserted into the patient intraoperatively. In the present embodiment, the implant 6 is a hip joint, and the implant model 6' is a corresponding digitalHip implant model. The control unit 2 has a calculation unit as a subunit (not shown), which calculates simulated loads based on the read-in implant parameters using predefined forces and moments on and acting on the implant model 6' and performs numerical simulations with respect to mechanical loads. Based on the at least one read-in implant parameter, the control unit 2 (or the calculation unit) determines whether the load limits associated with the implant model 6' are met for the numerically simulated loads. Finally, the control unit 2 controls the display device 4 to output the results of the simulation and calculation to the medical personnel. If the control unit 2 determines that the load limits are met for the simulated loads on the implant model 6', it outputs a visual confirmation via the operating room monitor.for example, in the form of text or a graphic, from which the surgeon can clearly determine the admissibility of the selected implant model 6'. However, if the control unit 2 determines that the load limits have been exceeded, it controls the operating room monitor in such a way that a visual warning is issued before the implant model is selected. In addition, an acoustic warning signal is emitted via a loudspeaker (not shown). In this way, a load, in particular a predefined load profile, is taken into account when selecting the implant or implant model, and the medical staff is given feedback as to whether the selected implant 6 or implant model 6' is suitable for the patient. In this way, an optimal selection with a corresponding service life of the implant 6 can be individually assessed in advance, and the safety of the patient P can be increased. Fig. 2 shows aFlowchart of a preferred embodiment of a computer-implemented implant assistance method (hereinafter referred to as method) for a simulation and selection of at least one implant 6 for an optimized use or joint replacement during a surgical procedure on a patient P. AE2030P-WO-0016 2021P00201 WO 15 / 21 In a first step S1, the method reads in at least one implant parameter, here an implant dimension and a weight limit, of a selected implant model 6'. In a step S2, a calculation unit (or a control unit 2 with a calculation unit) and on the basis of the at least one read-in implant parameter, follows, of simulated loads by predefined forces and moments on and on the implant model 6'. In a condition B3, it is determined in the method by the calculation unit and on the basis of the at least one read-in implant-Parameter, whether the load limits of the implant model 6' are met under the simulated loads. If condition B3 is positive and the load limits are met, a visual confirmation of the selection of the implant model 6' is output via a display device 4 in a step S4. If, however, it is determined in condition B3 that at least one load limit has been exceeded, the method proceeds to step S5, in which a visual warning is output via the display device before the selection of the implant model 6'. In particular, in step S5, the specific exceedance of the force or moment at the specific location of the implant model 6' can also be output in order to provide the medical personnel with feedback for further optimization of the selection of the implant model. The control unit 2 can also be adapted to generate aImplant model, to provide a suggestion for a further, second implant model that complies with the load limits. Alternatively or additionally, the control unit 2 can be adapted to calculate an implant orientation and output an optimal implant orientation that best complies with the load limits. AE2030P-WO-0016 2021P00201 WO 16 / 21 List of reference symbols 1 Implant assistance system 2 Control unit 4 Display device 6 Implant 6' Implant model P Patient S1 Step: Read in implant parameters S2 Calculate simulated loads on and at the implant model B3 Determine whether load limits are being complied with? S4 Output a confirmation of the selection of the implant model S5 Output a warning before selecting the implant model

Claims

AE2030P-WO-0016 2021P00201 WO 17 / 21 Claims 1. Computer-implemented implant assistance method for simulating and selecting at least one implant (6) for optimized use or joint replacement during a surgical procedure on a patient (P), characterized by the steps: reading (S1) at least one implant parameter, in particular at least one implant dimension and / or a weight limit, of a selected implant model (6'); calculating (S2), by a computation unit and based on the at least one read-in implant parameter, simulated dynamic loads by predefined forces and moments on and at the implant model (6') of a load situation of a dynamic activity, in particular walking or running;Determine (B3), using the calculation unit and based on at least one imported implant parameter, whether the load limits of the implant model (6') are met under the simulated loads;and output, by means of a display device (4), a visual confirmation (S4) of a selection of the implant model (6') if the load limits are observed, or output of a visual warning (S5) before the selection of the implant model (6') if the load limits are exceeded.

2. Computer-implemented implant assistance method according to claim 1, characterized in that the step Calculating (S2) of simulated loads replicates a load situation of a dynamic activity, a load situation scaled to 100 kg, on the implant model, which is obtained from measurement data of an instrumented knee prosthesis.

3. Computer-implemented implant assistance method according to claim 1 or 2, characterized in that in the step Calculating (S2) of simulated loads, a standardized load test according to standard ISO 14879-1 or according to standard ISO 14243 is used as a basis and simulated and calculated accordingly. AE2030P-WO-0016 2021P00201 WO 18 / 21 4. Computer-implemented implant assistance method according to one of the preceding claims, characterized in that the at least one implant parameter is an implant type and / or an implant size and / or an implant dimension and / or a weight limit and / or a position and orientation of the at least one selected implant model (6').

5. Computer-implemented implant assistance method according to one of the preceding claims, characterized in that the step Calculating (S2) of simulated loads includes the weight of the patient (P) and / or a muscular parameter of the patient (P) as a patient parameter and scales the simulated loads with the weight to provide patient-specific calculation and selection. 6.A computer-implemented implant assistance method according to one of the preceding claims, characterized in that the method further comprises the step of: reading in a patient's anatomy by reading in three-dimensional images of the patient (P), in particular MRI scans and / or CT scans and / or X-ray images, in order to create a simulation model with a patient model and the implant model and to perform the calculation step even more accurately, based on a three-dimensional section of a skeletal model and / or a musculoskeletal model of the patient (P). 7.Computer-implemented implant assistance method according to one of the preceding claims, characterized in that the method, in the step of issuing the visual warning (S5) when the load limits are exceeded, further comprises the step of: issuing, based on a stored implant data set, an implant model with a modified implant size and / or implant orientation which complies with the load limits. AE2030P-WO-0016 2021P00201 WO 19 / 21 8. Computer-implemented implant assistance method according to one of the preceding claims, characterized in that the method further comprises the steps of: acquiring, in particular prior to an incision, the kinematics of a joint of the patient (P) by means of a navigation system or a tracking system, in particular by means of detectable markers attached to the joint or by means of inertial measurement units attached to the joint; determining, based on the acquired kinematics of the patient (P), a kinematic phenotype; and outputting, based on the phenotype, a suggestion of an implant type and / or an implant orientation. 9.A computer-implemented implant assistance method according to one of the preceding claims, characterized in that, in addition to the at least one implant parameter, a further parameter relating to ground reaction forces and / or electromyography data and / or moving images, in particular from a fluoroscope, is read in order to simulate the course of patient kinematics and to determine, by inverse kinematics, a time course of the predefined forces and moments on and at the selected implant model (6'), which are used as simulated loads in the calculation step. 10.A computer-implemented implant assistance method according to one of the preceding claims, characterized in that the method further comprises the steps of: creating a multidimensional matrix based on a variance of input parameters; determining limits / boundary parameters that must be observed in the respective combination of input parameters so that the load limits are met; preferably outputting, depending on a patient weight and an implant size, an output parameter varus / valgus angle at which the implant can be inserted without exceeding the load limits; and. AE2030P-WO-0016 2021P00201 WO 20 / 21 preferably outputs a confirmation if a combination of the input parameters is within the defined limits or outputs a warning if a combination of the input parameters is outside the defined limits.

11. Implant assistance system (1) for simulating and selecting at least one implant for optimized use or joint replacement during a surgical procedure on a patient (P), comprising a display device (4), in particular an operating room monitor, for outputting visual content, characterized by a control unit (2) adapted for: reading in at least one implant parameter, in particular at least one implant dimension and / or a weight limit, of a selected implant model (6');Based on at least one input implant parameter, simulated dynamic loads are calculated by predefined forces and moments on and at the implant model (6') during a load situation of a dynamic activity, in particular walking or running; based on at least one input implant parameter, it is determined whether the load limits of the implant model (6') are observed under the simulated loads; and the display device (4) provides visual confirmation of the selection of the implant model (6') if the load limits are observed, or issues a visual warning before selecting the implant model (6') if the load limits are exceeded.

12. Computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to execute the method according to any one of claims 1 to 10.

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