Foot bottom deep soft tissue injury risk assessment method based on macro-mesomechanical conduction model
Through a method based on the macro-mesoscopic mechanics conduction model, the sole data is collected using multi-dimensional force plates, a cross-scale model is established and the degree of microvascular closure is calculated, which solves the problem of inaccurate evaluation in the prior art, and the accurate assessment of the risk of deep soft tissue damage is achieved.
Patent Information
- Application Number
- CN202510207619.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2025-07-18
AI Technical Summary
The prior art lacks physiological indicators when evaluating deep soft tissue injury in the soles of the foot, resulting in inaccurate assessment, especially in the case of diseases such as diabetic foot, deep tissue injury is difficult to be directly observed and difficult to diagnose and prevent.
Using a macro-mesoscopic mechanics conduction model, the multidimensional force data of the sole of the foot is collected through multi-dimensional force plates, a macro-mesoscopic cross-scale model was established, and the microvascular parameters were combined with microvascular parameters to calculate the microvascular closure degree parameters and evaluate the risk of soft tissue damage.
Accurate assessment of the risk of deep soft tissue damage is achieved, combining internal physiological parameters such as microvascular health status and local blood supply, improving the accuracy of the assessment.
Smart Images
Figure CN120323938A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of soft tissue injury risk assessment, and particularly relates to a method for assessing the risk of deep soft tissue injury of the sole of the foot. Background Art
[0002] In some diseases, such as diabetic foot, which result in limited lower limb mobility, damaged peripheral nerves in the foot, and reduced soft tissue tolerance, the incidence of deep tissue injury is increasing. Taking diabetic foot as an example, deep soft tissue injury of the sole usually occurs near the bony prominences, such as under the metatarsal bones and the calcaneus. The characteristic of this kind of injury is that it starts from the interface between bone and soft tissue and gradually develops to the skin surface. Due to its deep location, it is often difficult to be directly observed, which also makes the diagnosis and prevention of this kind of injury more challenging. Existing sole soft tissue injury assessment techniques mostly focus on realizing risk assessment and prediction through skin surface pressure monitoring. For example, Chinese invention patents CN113796852B, CN114748044A, CN117643402A, CN109602423B, etc. all belong to the assessment of the risk of sole soft tissue injury based on sole pressure parameters. However, the occurrence of soft tissue injury is not only related to external factors such as sole pressure, but also involves multiple internal physiological factors such as the blood circulation status of deep tissues, the internal mechanical conduction of tissues, and the health status of microvessels. Foot soft tissue injury is the result of the combined action of multiple factors such as mechanics, physiology, and structure. Therefore, the method of simply identifying the risk of soft tissue injury by the pressure acting on the sole skin cannot accurately reflect the risk of soft tissue injury, and internal physiological parameters such as the health status of microvessels and local blood supply must be combined to improve the accuracy of risk assessment. Summary of the Invention
[0003] The purpose of the present invention is to provide a method for assessing the risk of deep soft tissue injury of the sole based on a macro-mesoscopic mechanical conduction model with high assessment accuracy, so as to realize the risk assessment of soft tissue injury with physiological indicators.
[0004] The method for assessing the risk of deep soft tissue injury of the sole based on the macro-mesoscopic mechanical conduction model provided by the present invention assesses the risk of deep sole soft tissue injury through a cross-scale biomechanical method including microvessels; the specific steps are as follows:
[0005] Step 1, use a multi-dimensional force plate to collect multi-dimensional force data of the sole during gait;
[0006] Step 2, establish a macro-meso cross-scale model: Based on the foot image, divide the foot structure, establish a macro foot geometric model (macro is in millimeters), cut out the meso geometric model from the macro foot geometric model (meso is in micrometers), in the meso geometric model, establish a meso geometric model containing microvessels according to the microvascular parameters, establish a macro foot model and a meso microvascular model through mechanical analysis techniques, and perform cross-scale coupling on the macro foot model and the meso microvascular model to solve and calculate;
[0007] Step 3, calculate the microvascular closure degree parameter of the soft tissue;
[0008] Step 4, evaluate the risk of soft tissue injury.
[0009] Furthermore:
[0010] In Step 1, the multi-dimensional foot force data is the pressure and shear force in the foot area.
[0011] In Step 2, the specific process of establishing the macro-meso cross-scale model is as follows:
[0012] Step 2-1, convert the foot image into a grayscale image, divide the foot into four parts: skin, fat, muscle, and bone according to the grayscale difference between foot tissues to obtain the macro foot geometric model; cut out the meso geometric model from the macro foot geometric model, and the boundary between the meso geometric model and the macro foot geometric model is Establish randomly distributed microvessels in the meso geometric model according to the microvascular parameters to obtain a meso geometric model containing microvessels;
[0013] Step 2-2, through mechanical analysis techniques, for example, in finite element software, assign corresponding material properties to the skin, fat, muscle, and bone of the macro foot geometric model respectively, and perform mesh division on the macro foot geometric model to obtain the macro foot model; subsequently, assign material properties to the microvessels in the meso geometric model containing microvessels and perform mesh division to obtain the meso microvascular model;
[0014] Step 2-3, perform cross-scale coupling on the macro foot model and the meso microvascular model, and the specific process is as follows:
[0015] Take the foot sole pressure and shear force obtained in Step 1 as boundary conditions to drive the solution and calculation of the macro foot model (for example, take the actually measured physical quantities such as foot sole pressure and shear force as inputs, apply them to the macro finite element model of the foot, and then obtain the stress, deformation, strain and other physical responses of the foot under these loads through numerical calculation), and obtain the displacement field u of the nodes on the boundary of the macro foot model of the macro foot model macro(x); According to the principle of strain energy balance, the displacements and forces of two adjacent parts are continuous at the boundary. Thus, the strain energies of the two parts are equal at the boundary, that is:
[0016]
[0017] where W macro is the strain energy density of the macroscopic model, and W meso is the strain energy density of the mesoscopic model;
[0018] Since the displacements are continuous at the boundary, taking the displacement results of the macroscopic foot model as the boundary conditions of the mesoscopic microvascular model can ensure energy conservation. The implementation method for the cross-scale coupling of the macroscopic-mesoscopic model is: making the displacement field u of the nodes on the boundary of the mesoscopic microvascular model equal to the displacement field u meso (x) of the nodes on the boundary of the macroscopic foot model, that is: The displacement of the nodes on the boundary of the mesoscopic microvascular model defines the response of the boundary of the mesoscopic microvascular model, thereby driving the mechanical behavior inside the mesoscopic microvascular model. macro (x), that is:
[0019]
[0020] On the boundary of the mesoscopic microvascular model, the displacement of the nodes defines the response of the boundary of the mesoscopic microvascular model, thereby driving the mechanical behavior inside the mesoscopic microvascular model.
[0021] In step 3, the process of calculating the microvascular closure degree parameter is as follows:
[0022] Step 3-1: Extract the geometric shapes of the microvessels in the mesoscopic microvascular model in the undeformed and deformed states;
[0023] Step 3-2: According to the microvascular geometric shapes obtained in step 3-1, calculate the microvascular closure degree K, and the formula is as follows:
[0024]
[0025] In the formula, ∑A unload represents the sum of the cross-sectional areas of all microvessels in the mesoscopic microvascular model in the undeformed state, and ∑A load represents the sum of the cross-sectional areas of all microvessels in the mesoscopic microvascular model in the deformed state.
[0026] In step 4, the process of evaluating the risk of soft tissue injury is as follows: compare the degree of microvascular closure K calculated in step 3 with the microvascular closure threshold (the microvascular closure threshold is the result of comprehensively considering tissue mechanics, vascular physiology, etc., and can be determined by experience combined with experiments). If K is much smaller than the microvascular closure threshold, the microcirculation state is good, and it is determined that there is no risk of soft tissue injury; if K is smaller but close to the microvascular closure threshold, the microcirculation state is poor, and it is determined that there is a low risk of soft tissue injury; if K is greater than the microvascular closure threshold, the microcirculation state is blocked, and it is determined that there is a high risk of soft tissue injury.
[0027] The present invention also includes a plantar deep soft tissue injury risk assessment system based on a macro-mesoscopic mechanical conduction model, which specifically includes the following four modules: a multi-dimensional plantar force data acquisition module during gait; a macro-mesoscopic cross-scale model construction module, a parameter calculation module for the degree of microvascular closure of soft tissues, and a soft tissue injury risk assessment module; these four modules respectively perform the operations of the four steps in the plantar deep soft tissue injury risk assessment method.
[0028] Compared with the traditional method, the present invention has the following advantages:
[0029] During the risk assessment process, it includes the response of soft tissues to multi-dimensional plantar forces at the microvascular physiological level, realizing a soft tissue injury risk assessment with truly physiological indicators; establishing the correlation between the force on the skin surface and the physiological response of deep soft tissue microcirculation, thereby establishing the "threshold" for deep soft tissue injury and providing technical support for accurately assessing the risk of deep soft tissue injury. Brief Description of the Drawings
[0030] Figure 1 is a flowchart of the deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanical conduction model of the present invention.
[0031] Figure 2 is a grayscale image of each tissue of the foot including the mesoscopic model.
[0032] Figure 3 is the effect diagram of the macroscopic foot finite element modeling established in the embodiment of the present invention.
[0033] Figure 4 is a schematic diagram of the mesoscopic microvascular model established in the embodiment of the present invention.
[0034] Figure 5 is the microvascular deformation diagram of several different degrees of closure solved according to the macro-mesoscopic cross-scale model in the embodiment of the present invention. Detailed Embodiments
[0035] The present invention will be further introduced below through embodiments in combination with the drawings.
[0036] The method for assessing the risk of deep soft tissue injury based on the macro-mesoscopic mechanics conduction model of the present invention has a process as follows Figure 1 shown, and the specific steps are as follows:
[0037] Step 1: Use a multi-dimensional force plate to collect multi-dimensional foot force data during gait;
[0038] Step 2: Establish a macro-mesoscopic cross-scale model: Based on foot images, divide the foot structure, establish a macro foot geometric model, cut out a mesoscopic geometric model from the macro foot geometric model. In the mesoscopic geometric model, establish a mesoscopic geometric model containing microvessels according to microvascular parameters, establish a macro foot model and a mesoscopic microvascular model through mechanical analysis techniques, and perform cross-scale coupling on the macro foot model and the mesoscopic microvascular model for solution calculation;
[0039] Step 3: Calculate the microvascular closure degree parameter;
[0040] Step 4: Evaluate the risk of soft tissue injury.
[0041] The above steps will be described in detail below.
[0042] Step 1: Use a multi-dimensional force plate to collect multi-dimensional foot force data during gait: Use a multi-dimensional force plate to collect the multi-dimensional force data of the gait, and the obtained multi-dimensional force data of the gait are the peak pressure and shear force of the sole area.
[0043] Step 2: Establish a macro-mesoscopic cross-scale model: Based on foot images, divide the foot structure, establish a macro foot geometric model, cut out a mesoscopic geometric model from the macro foot geometric model. In the mesoscopic geometric model, establish a mesoscopic geometric model containing microvessels according to microvascular parameters, establish a macro foot model and a mesoscopic microvascular model through mechanical analysis techniques, and perform cross-scale coupling on the macro foot model and the mesoscopic microvascular model for solution calculation.
[0044] Figure 2 is the grayscale image of each tissue of the foot containing the mesoscopic model.
[0045] Figure 3 is the effect diagram of the macro foot finite element modeling established in the embodiment of the present invention.
[0046] In Step 2, the process of establishing the macro-mesoscopic cross-scale model includes the following sub-steps:
[0047] Step 2-1: Convert the foot image into a grayscale image, and divide the foot into four parts, namely skin, fat, muscle, and bone as shown Figure 2 shown, and reconstruct the foot geometric model; Through mechanical analysis techniques, such as meshing and material property assignment to the foot geometric model in finite element software, realize the transformation from the geometric model to the physical model, and obtain asFigure 3 The macroscopic hierarchical finite element model of the foot shown;
[0048] Figure 4 It is a schematic diagram of the mesoscopic microvascular model established in the embodiment of the present invention.
[0049] Step 2-2: Cut out the mesoscopic model from the macroscopic model. The mesoscopic model is located at the high-incidence site of diabetic foot ulcers, that is, below the bone prominence, as Figure 2 shown, with a size of 460μm×460μm; the boundary between the mesoscopic model and the macroscopic model is Ω; to reduce the boundary effect, according to the Saint–Venant principle, a 300μm×300μm area in the middle of the mesoscopic model is selected as the microvascular distribution area (as Figure 4 shown); the outer diameter of the microvessel is 10μm, the wall thickness of the microvessel is 1μm, and the total area of the microvessels accounts for 2% of the area of this region. Based on the above parameters, randomly distributed microvessels are established; the mesoscopic model containing microvessels is remeshed and material properties are assigned to obtain the mesoscopic microvascular model;
[0050] Step 2-3: The specific process of cross-scale coupling of the macro-mesoscopic model is as follows:
[0051] Use the plantar pressure and shear force obtained in Step 1 as boundary conditions to drive the solution calculation of the macroscopic foot model, and obtain the displacement field u of the nodes on the boundary of the macroscopic foot model macro (x); based on the principle of strain energy balance, the displacements and surface forces of two adjacent parts are continuous on the boundary, so the strain energies of these two parts on the boundary are also equal, that is:
[0052]
[0053] where W macro is the strain energy density of the macroscopic model, and W meso is the strain energy density of the mesoscopic model;
[0054] Since the displacements are continuous on the boundary, the displacement results of the macroscopic model are used as the boundary conditions of the mesoscopic model to ensure energy conservation; the implementation method of cross-scale coupling of the macro-mesoscopic model is: make the displacement field u of the nodes on the boundary of the mesoscopic model meso (x) equal to the displacement field u of the nodes on the boundary of the macroscopic model macro (x), that is:
[0055]
[0056] The mesoscopic model on the boundary The displacement of the upper node defines the response of the mesoscopic model boundary, thereby driving the mechanical behavior inside the mesoscopic model.
[0057] In step 3, calculating the microvascular closure degree parameter includes the following sub-steps:
[0058] Step 3-1, extract the geometric morphology of the microvessels in the undeformed and deformed states of the mesoscopic model;
[0059] Step 3-2, based on the microvascular geometric morphology obtained in 3-1, calculate the microvascular closure degree K, and the formula is as follows:
[0060]
[0061] In the formula, ∑A unload represents the sum of the cross-sectional areas of all microvessels in the mesoscopic model in the undeformed state, and ∑A load represents the sum of the cross-sectional areas of all microvessels in the mesoscopic model in the deformed state.
[0062] Figure 5 is the microvascular deformation diagram when the closure degree K = 1.1, 2.3, 50 solved according to the macro-mesoscopic cross-scale model in the embodiment of the present invention.
[0063] In step 4, the specific process of evaluating the risk of soft tissue injury is as follows: compare the microvascular closure degree K calculated in step 3 with the microvascular closure threshold. If K is much smaller than the microvascular closure threshold, the microcirculation state is good, and it is determined that there is no risk of soft tissue injury; if K is less than but close to the microvascular closure threshold, the microcirculation state is poor, and it is determined that there is a low risk of soft tissue injury; if K is greater than the microvascular closure threshold, the microcirculation state is blocked, and it is determined that there is a high risk of soft tissue injury.
[0064] Compared with the traditional method, the deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanical conduction model of the present invention includes the response of soft tissue to the multi-dimensional force on the sole at the physiological level of microvessels during the risk assessment process, realizing a soft tissue injury risk assessment with truly physiological indicators; establishing the correlation between the force on the skin surface and the physiological response of deep soft tissue microcirculation, and based on this, establishing the "threshold" of deep soft tissue injury, providing new technical support for accurately assessing the risk of deep soft tissue injury.
[0065] The above embodiments are preferred cases of the present invention and are not used to limit the protection scope of the present invention.
Claims
1. A method for assessing the risk of deep plantar soft tissue injury based on a macro-mesoscopic mechanical conduction model, which is used to assess the risk of deep plantar soft tissue injury through a cross-scale biomechanical method including microvessels; characterized in that, Including: Step 1: Collect multi-dimensional plantar force data during gait using a multi-dimensional force plate. Step 2: Establish a macro-mesoscopic cross-scale model. Divide the foot structure based on foot images to establish a macroscopic foot geometric model (macroscopic scale is in millimeters). Cut out a mesoscopic geometric model from the macroscopic foot geometric model (mesoscopic scale is in micrometers). In the mesoscopic geometric model, establish a mesoscopic geometric model containing microvessels according to microvascular parameters. Establish a macroscopic foot model and a mesoscopic microvascular model through mechanical analysis techniques, and perform cross-scale coupling of the macroscopic foot model and the mesoscopic microvascular model, and solve the calculation. Step 3: Calculate the microvascular closure degree parameter of soft tissues. Step 4: Evaluate the risk of soft tissue injury.
2. The plantar deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanics conduction model according to claim 1, wherein The multi-dimensional plantar force data described in Step 1 is the pressure and shear force in the plantar region.
3. The plantar deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanics conduction model according to claim 2, wherein The specific process of establishing the macro-mesoscopic cross-scale model described in Step 2 is as follows: Step 2-1: Convert the foot image into a grayscale image, divide the foot into four parts: skin, fat, muscle, and bone according to the grayscale differences between foot tissues to obtain a macroscopic foot geometric model; cut out a mesoscopic geometric model from the macroscopic foot geometric model, and the boundary between the mesoscopic geometric model and the macroscopic foot geometric model is Establish randomly distributed microvessels in the mesoscopic geometric model according to the microvascular parameters to obtain a mesoscopic geometric model containing microvessels; Step 2-2: Through mechanical analysis techniques, for example, in finite element software, assign corresponding material properties to the skin, fat, muscle, and bone of the macroscopic foot geometric model respectively, and perform mesh division on the macroscopic foot geometric model to obtain a macroscopic foot model. Subsequently, assign material properties to the microvessels in the mesoscopic geometric model containing microvessels and perform mesh division to obtain a mesoscopic microvascular model. Step 2-3: Perform cross-scale coupling of the macroscopic foot model and the mesoscopic microvascular model. The specific process is as follows: Taking the plantar pressure and shear force obtained in Step 1 as boundary conditions, driving the solution calculation of the macroscopic foot model, and obtaining the displacement field u (x) of the nodes on the boundary; according to the principle of strain energy balance, the displacements and forces of two adjacent parts are continuous on the boundary, so the strain energies of the two parts are equal on the boundary, that is: macro (x); According to the principle of strain energy balance, the displacements and forces of two adjacent parts are continuous on the boundary, so the strain energies of the two parts are equal on the boundary, that is: Among them, W macro is the strain energy density of the macroscopic model, and W meso is the strain energy density of the mesoscopic model; Since the displacement is continuous at the boundary, using the displacement result of the macroscopic foot model as the boundary condition of the mesoscopic microvascular model can ensure energy conservation. The implementation method of the macroscopic-mesoscopic model for cross-scale coupling is as follows: Let the displacement field u of the nodes on the boundary meso (x) of the mesoscopic microvascular model be equal to the displacement field u of the nodes on the boundary macro (x) of the macroscopic foot model, that is: The displacement of the nodes on the boundary of the mesoscopic microvascular model defines the response of the boundary of the mesoscopic microvascular model, thus driving the mechanical behavior inside the mesoscopic microvascular model.
4. The plantar deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanics conduction model according to claim 3, characterized in that The process of calculating the microvascular closure degree parameter described in Step 3 is as follows: Step 3-1: Extract the geometric morphology of the microvessels in the mesoscopic microvascular model in the undeformed and deformed states. Step 3-2: According to the microvascular geometric morphology obtained in Step 3-1, calculate the microvascular closure degree K. The formula is as follows: where ∑A unload represents the sum of the cross-sectional areas of all microvessels in the mesoscopic microvessel model in the undeformed state, and ∑A load represents the sum of the cross-sectional areas of all microvessels in the mesoscopic microvessel model in the deformed state.
5. The plantar deep soft tissue injury risk assessment method based on the macro-mesoscopic mechanics conduction model according to claim 4, characterized in that The specific process of evaluating the risk of soft tissue injury described in Step 4 is as follows: Compare the microvascular closure degree K calculated in Step 3 with the microvascular closure threshold. If K is much smaller than the microvascular closure threshold, the microcirculation state is good, and it is determined that there is no risk of soft tissue injury. If K is less than but close to the microvascular closure threshold, the microcirculation state is poor, and it is determined that there is a low risk of soft tissue injury. If K is greater than the microvascular closure threshold, the microcirculation state is blocked, and it is determined that there is a high risk of soft tissue injury.