Article of footwear for early intervention of knee osteoarthritis

Abstract

An article of footwear that provides early intervention of knee osteoarthritis to a user. The article of footwear includes a sole comprised of a plurality of structures. The plurality of structures are at least partially spaced apart. The plurality of structures have different settings at the plurality of zones of the sole to provide the plurality of zones having respective stiffness that varies between the plurality of three-dimensional zones. The plurality of zones includes a target zone characterized by having a stiffness lower than any corresponding stiffness of any other zone. The target section is shaped at the sole and positioned to coincide with the user's barefoot pressure centerline. The barefoot pressure centerline may be measured relative to a user in barefoot walking movement. The article of footwear may be in the form of a shoe or in the form of a foot brace.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to Singapore patent application No. 10202251586Y filed on November 2, 2022, the contents of which are hereby incorporated by reference in its entirety for all purposes. Technical Field

[0002] The present application relates to an article of footwear, and more particularly to a device worn on the foot for early intervention of knee osteoarthritis. Background Art

[0003] Osteoarthritis of the knee is one of the most common types of osteoarthritis. There are two main methods for treating knee osteoarthritis, namely surgery and medication. Surgical treatments include knee replacement, arthroscopy to promote cartilage growth, and osteotomy to remove bone around the joint. An alternative is medication, such as injecting steroids or hyaluronic acid derivatives in or around the knee joint, which can help reduce pain for several months. Summary of the invention

[0004] A footwear article for providing early intervention of knee osteoarthritis for a user, the footwear article comprising an upper portion and a sole. The sole is composed of a plurality of structures. The plurality of structures are at least partially spaced apart. The plurality of structures have different settings in a plurality of regions of the sole to provide a plurality of regions with corresponding stiffnesses that change between the plurality of regions. The plurality of regions are three-dimensional. The plurality of regions include a target region, the target region being characterized by having a stiffness lower than any corresponding stiffness of any other region. The target region is shaped on the sole and positioned to coincide with the user's barefoot center of pressure (COP) line. The barefoot COP line can be set based on data of a user in barefoot walking and / or data of a group of healthy individuals without known symptoms or risk factors of knee osteoarthritis. The user has a COP line that can be measured relative to the user in motion and a barefoot COP line that can be measured relative to the user in barefoot walking motion. The sole has an outer surface and an inner surface. The sole is coupled to the upper portion so that the inner surface and the upper portion can cooperatively accommodate the user's foot.

[0005] Different arrangements of the multiple structures provide multiple stiffness gradients in the sole in different orientations, each of the multiple stiffness gradients forces the COP line to dynamically shift toward the barefoot COP line.

[0006] A plurality of stiffness gradients are provided with decreasing stiffness along different orientations along the plurality of stiffness gradients toward the target region.

[0007] Multiple structures allow the foot to move freely during movement, with multiple zones providing force absorption and localized support for the foot.

[0008] Each of the plurality of zones is characterized by a local stiffness, wherein the target zone constitutes a contiguous zone characterized by a local stiffness that is lower than any local stiffness of any other zone.

[0009] The plurality of structures may include a plurality of bump structures, wherein adjacent bump structures in the plurality of bump structures are spaced apart to define a spacer network.

[0010] The sole may include a base layer having a plurality of structures protruding from the base layer, wherein a sole thickness of the sole is comprised of a thickness of the base layer and a length of one of the plurality of structures.

[0011] In any one of the plurality of sections, the plurality of structures may be disposed approximately for lengths of the plurality of structures.

[0012] Each of the plurality of sections may be made of a resilient foam and / or an additively molded metamaterial structure. At least two adjacent sections of the plurality of sections may be made as detachable pieces of resilient foam and / or an additively molded metamaterial structure having different stiffnesses. At least two adjacent sections of the plurality of sections may be made with complementary shapes.

[0013] At least two adjacent sections of the plurality of sections may include differently arranged structures, wherein at least two adjacent sections of the plurality of sections may be characterized by having different stiffnesses. At least two adjacent sections of the plurality of sections may include different densities of the plurality of structures. At least two adjacent sections of the plurality of sections may include several structures of the plurality of structures that are differently shaped. At least two adjacent sections of the plurality of sections may include several structures of the plurality of structures that are differently sized. At least two adjacent sections of the plurality of sections may include multiple structures made of different material stiffnesses.

[0014] Each of the plurality of zones may include a network of primary material defining compressible structures and / or cavities distributed therein, wherein the respective stiffness of each of the plurality of zones is related to the distribution density of the compressible structures and / or cavities.

[0015] The sole may include a base layer defining an inner surface of the sole, wherein the plurality of structures within any one of the plurality of regions are similarly arranged throughout the sole thickness of the sole.

[0016] The sole may include a base layer, wherein each of the plurality of regions is characterized by a bending stiffness that is related to a thickness gradient of the base layer to which the plurality of structures are coupled.

[0017] The sole may include an insole providing an inner surface and an outsole providing an outer surface, wherein a plurality of structures are disposed on the outsole.

[0018] The footwear article further comprises a midsole, which is arranged between the insole and the outsole. The midsole and the outsole can be made with a plurality of structures and / or a plurality of cavities that are arranged differently in the plurality of structures and / or cavities. The midsole and the outsole can be made with a plurality of structures and / or a plurality of cavities that are arranged similarly in the plurality of structures and / or cavities.

[0019] The midsole and outsole may be additively molded as a one-piece component. Alternatively, the sole may include one or more joint-type pivot structures, wherein the sole includes at least two sections coupled by a joint. The joint may have multiple degrees of freedom.

[0020] The sole can be set based on a method, which includes: determining the position of the user's pressure center line relative to the sole, the pressure center line being obtained based on any one or both of (i) data of the user walking barefoot and (ii) data of a group of healthy people; setting a target area so that the pressure center line corresponds to the center line of the target area; and setting the stiffness of the target area and the corresponding stiffness of other areas in the multiple areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Different embodiments of the present application are described below with reference to the following drawings:

[0022] Figure 1A and Figure 1B is a schematic diagram of a sole of a footwear article according to different embodiments of the present application;

[0023] Figure 2A is a top view of the sole, which shows the distribution of the cavities opened to the inner surface of the sole;

[0024] Figure 2B yes Figure 2A a side view of the sole shown;

[0025] Figure 2C yes Figure 2A a cross-sectional bottom view of the sole shown;

[0026] Figure 2D yes Figure 2C an enlarged view of a portion of;

[0027] Figure 3A is an exploded bottom perspective view of a schematic diagram of a shoe sole according to some embodiments of the present application;

[0028] Figure 3B yes Figure 3A a top perspective view of the sole shown;

[0029] Figure 4A is a cross-sectional side view of a sole of an embodiment of the present application;

[0030] Figure 4B yes Figure 4A a bottom view of the sole shown;

[0031] Figure 4C yes Figure 4B a schematic diagram of the outer sole shown, the schematic diagram showing a plurality of zones;

[0032] Figure 5A is a bottom view of an outsole according to another embodiment of the present application;

[0033] Figure 5B yes Figure 5A a schematic diagram of the outer sole shown;

[0034] Fig. 6A is a bottom view of a midsole according to some embodiments of the present application;

[0035] Figure 6B yes Fig. 6A a schematic diagram of the midsole shown, the schematic diagram showing a plurality of zones;

[0036] Figure 7 is an exploded top perspective view of a shoe sole according to one embodiment;

[0037] Figure 8 is an exploded top perspective view of a sole according to another embodiment;

[0038] Fig. 9 is a cross-sectional view of a sole according to another embodiment;

[0039] Fig. 10A is a top perspective view of a sole without a cavity opening on the inner surface;

[0040] Fig. 10B is a top perspective view of a sole having a cavity opening at an inner surface;

[0041] Fig.11A is a cross-sectional view showing a sole having a base layer;

[0042] Fig. 11B is a schematic bottom-up perspective view of a portion of a shoe sole;

[0043] Fig.12 It has a front cut. Fig. 10B a bottom perspective view of the sole shown;

[0044] Fig.13A method for determining a barefoot COP line or a barefoot COP zone is schematically shown;

[0045] FIG. 14A to FIG. 14D is a schematic diagram showing the correlation between ground forces and different embodiments of midsoles and outsoles;

[0046] Fig.15 shows a centre of pressure (COP) line plotted based on test results obtained for the present footwear prototype and compared with a target COP line and a COP line reported for conventional footwear;

[0047] Fig.16 An example of an article of footwear incorporating the present article of footwear is shown;

[0048] Fig.17 An example of a foot brace incorporating the present article of footwear is shown; and

[0049] 18A to 18C An example of a shoe sole of the present application having a joint-type pivot feature is shown. DETAILED DESCRIPTION

[0050] The following detailed description will be made with reference to the accompanying drawings, which show details and embodiments of the present application for illustrative purposes. Features described in the context of one embodiment may be correspondingly applicable to the same or similar features in other embodiments, even if not explicitly described in these other embodiments. Application and / or combination and / or substitution described for features in the context of one embodiment may be correspondingly applicable to the same or similar features in other embodiments.

[0051] In the context of various embodiments, the articles “a,” “an,” and “the” used with respect to features or elements include reference to one or more features or elements.

[0052] In the context of various embodiments, the terms "about" or "approximately" applied to numerical values ​​encompass both the exact value and a reasonable difference commonly understood in the relevant technical field, such as within 10% of the specified value.

[0053] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0054] According to various embodiments of the present application, the proposed footwear is intended to be worn by a user on the foot for use as an early intervention for knee osteoarthritis (OA). The sole can be used for early intervention for knee osteoarthritis, for example, to delay the onset of knee osteoarthritis for people with or without predisposed conditions. The device can be in the form of a footwear article, for example, a footwear article worn by a user as a pair of shoes, an insole or a foot support.

[0055] refer to Figures 1A to 2D , the present application describes different embodiments of a footwear article 200 that provides early intervention of knee osteoarthritis for a user, and more specifically, the present application describes different embodiments of a sole 250 that provides early intervention of knee osteoarthritis for a user. The footwear article 200 includes an upper portion and a sole 250. The sole 250 has an outer surface 514 and an inner surface 512. The sole 250 can be coupled to the upper portion so that the inner surface 512 and the upper portion can cooperatively accommodate the user's foot.

[0056] The user has a barefoot center of pressure (COP) line that can be measured when the user walks barefoot.

[0057] The article of footwear 200 can be worn by a user when walking on flat ground, wherein the target zone is flat or substantially flat as a whole, thereby providing uninterrupted physical contact between at least a portion of the target zone and the flat ground, to simulate, for example, barefoot walking. When the user walks in the article of footwear, the sole 250 or article of footwear 200 is configured to simulate barefoot walking, wherein the foot can move freely, or the sole 250 or article of footwear 200 offsets the user's COP line.

[0058] The term barefoot COP line used herein can be set for a user and can be a personal target COP set based on any one or combination of (i) data of the same user and / or (ii) data of a group of healthy people without symptoms or risk factors of knee osteoarthritis. If the same user walks barefoot, and it is assumed that the user has milder symptoms (or risk factors) of knee osteoarthritis or the user has no symptoms (or risk factors) of knee osteoarthritis, the barefoot COP line can also be understood as the COP of the user (the sole 250 is customized or specially made for the user). For example, the actual COP line of the user can be set based only on the user's measurement results, the universal target COP line can be set based on the data of a group of healthy individuals (the term "healthy" is understood in association with knee osteoarthritis), and the barefoot COP line can be set between the actual COP line of the user and the universal target COP line. For example, the user has a COP line that can be measured relative to the user in motion and a barefoot COP line that can be measured relative to the user in motion while walking barefoot.

[0059] Where a barefoot COP line is set, the sole 250 is then configured to facilitate or enable the user to walk at the barefoot COP line, for example, the sole 250 is configured to dynamically shift the user's movement or dynamic COP trajectory toward a target area in the footwear article, as will be described in detail below.

[0060] Assume that the user has a habitual walking style. The user can perform a series of gait assessments, and with the assistance of the plantar pressure map, the dynamic trajectory of the COP axis (a vertical imaginary line extending through the combined force at the moment when at least a portion of the foot contacts the ground) can be obtained. If the gait assessment is performed when the user is barefoot, the COP line is also called the barefoot COP line for simplicity. When the same test is performed on a user wearing conventional shoes, it is observed that the COP line deviates from the barefoot COP line. A reference is made to the offset of the COP line or the dynamic offset of the COP line. The footwear article of the present application includes a sole with a built-in biasing portion to dynamically change the user's walking posture, such as dynamically changing the user's walking posture while the user moves, such as dynamically changing the user's walking posture while the user walks in the footwear article. Different settings of multiple structures provide multiple stiffness gradients in different orientations and on the sole, and each of the multiple stiffness gradients forces the COP line to dynamically offset toward the barefoot COP line.

[0061] When the same test is performed on a user wearing the footwear presented herein, the footwear 200 (e.g., sole 250) will present a COP line that is closer to the barefoot COP line than the COP line when wearing conventional shoes. In a sense, the footwear 200 shifts the COP line to better follow or match the barefoot COP line.

[0062] like Figure 1A and Figure 1B As shown, the sole 250 includes a plurality of structures 540. The plurality of structures 540 can be variably arranged on a plurality of sections 600 of the sole 250 to provide a plurality of sections with corresponding stiffnesses that change between the plurality of sections. The plurality of sections are three-dimensional. The plurality of sections 600 include a target section 610, characterized in that it has a stiffness lower than any corresponding stiffness of any other section 630. The target section 610 is shaped and positioned to coincide with the barefoot COP line at the sole. Each section 600 can be characterized in that it has a local stiffness. The target section 610 can constitute a continuous section, characterized in that it has a local stiffness lower than the local stiffness of any other section 630.

[0063] like Figure 2CAs shown, different arrangements of multiple structures provide multiple stiffness gradients 560 in different orientations on the sole, wherein each of the multiple stiffness gradients forces the COP line to dynamically shift toward the barefoot COP line along a direction 564, for example, forces the COP line to dynamically shift from other regions 630 toward the target region 610. The multiple stiffness gradients 560 are arranged to have decreasing stiffness along the multiple stiffness gradients 564, along different orientations, toward the target region 610. The multiple structures 540 can be characterized by having a gradient 560 with decreasing stiffness toward the target region 610. The multiple structures allow the foot to move freely during movement, wherein the multiple regions provide force absorption and local support for the foot.

[0064] The term structure is used herein in the general sense of a piece of material. Some or all of the plurality of structures 540 may be in the form of bump structures 543, such as FIG. 2B to FIG. 2D As shown. The plurality of structures 540 may be interconnected (e.g., branched or in a network or matrix form) and at least partially spaced apart to define an interconnected network of spaces 546 (or valleys) between the bump structures 543. The cavities 530 may be defined in the structures 540, for example, each bump structure 543 may include a bump unit wall surrounding the cavity 530. The cavities may be formed on the inner surface 512 (e.g., Figure 2A 514) and / or open to the outside air. In some embodiments, the structure 540 can be interchangeably referred to as a strut and / or element of the metamaterial. In some other embodiments, each of the plurality of sections can include a network or body of a primary material with compressible cavities 530 set to be distributed therein, wherein the respective stiffness of each of the plurality of sections 600 is related to the distribution density of the compressible cavities 530. For example, in some other embodiments, the structure 540 refers to a foam material of a foam, wherein bubbles are distributed in the foam.

[0065] Figure 2D yes Figure 2C, which is enlarged to better illustrate the example of the sole 250 with a lug structure 543, only for auxiliary understanding and illustration purposes. Each lug structure 543 can be a protruding material block extending away from the base layer. At least two adjacent sections in a plurality of sections 600 may include several structures, several intervals and / or several cavities that are differently arranged in a plurality of structures 540, a plurality of intervals 546 and / or a plurality of cavities 530, wherein at least two adjacent sections in a plurality of sections 600 are characterized in that they have different rigidities. At least two adjacent sections in a plurality of sections 600 may include different densities of a plurality of structures 540, a plurality of intervals 546 and / or a plurality of cavities 530. At least two adjacent sections in a plurality of sections 600 may include several structures, several intervals and / or several cavities that are differently shaped in a plurality of structures 540, a plurality of intervals 546 and / or a plurality of cavities 530. At least two adjacent sections in the plurality of sections 600 may include differently sized structures, spaces, and / or cavities in the plurality of structures 540, spaces 546, and / or cavities 530. At least two adjacent sections in the plurality of sections 600 may include bump structures 540 made with different material stiffnesses.

[0066] The sole 250 may include a base layer 520 , wherein each of the plurality of zones 600 is characterized by having a stiffness associated with a thickness gradient of the base layer 520 , and a structure 540 with / without a cavity 530 coupled to the base layer 520 .

[0067] The sole 250 includes an insole 300 providing an inner surface 312 and an outer surface 514, and wherein a plurality of structures 540 are disposed on the outer surface. The sole 250 may further include a midsole 400, wherein the midsole 400 is disposed between the insole 300 and the outer surface 500.

[0068] The midsole 400 and the outsole 500 may be manufactured with several structures, several spaces and / or several cavities arranged differently in the plurality of structures 540, the plurality of spaces 546 and / or the plurality of cavities 530. The midsole 400 and the outsole 500 may be manufactured with several structures, several spaces and / or several cavities arranged similarly in the plurality of structures 540, the plurality of spaces 546 and / or the plurality of cavities 530. The sole may include a base layer defining an inner surface of the sole, wherein the plurality of structures in any one of the plurality of sections are similarly arranged throughout the sole thickness of the sole.

[0069] The midsole 400 and the outsole 500 may be additively molded as a one-piece component. In other embodiments, the sole may include one or more joint-type pivot features, wherein the sole is made as a plurality of separate components that may be connected by complementary joint-type pivot features in the plurality of joint-type pivot features.

[0070] The insole 300 may be shaped with a flange partially along the perimeter of the heel region, and wherein the insole 300 is dimensioned according to the contour of the foot under non-weight bearing conditions.

[0071] A sole can be set based on a method, which includes: determining the position of a user's pressure centerline relative to the sole, the pressure centerline being based on either or both of (i) data of the user walking barefoot and (ii) data of a group of healthy people; setting a target area so that the pressure centerline corresponds to the centerline of the target area; and setting the stiffness of the target area and the corresponding stiffness of other areas in a plurality of areas.

[0072] In other words, according to some embodiments of the present application, the article of footwear 200 includes a sole 250 including an insole 300 , a midsole 400 , and an outsole 500 . Figure 3A The sole 250 is shown in an exploded bottom perspective view, and Figure 3B The sole 250 is shown in an exploded top perspective view.

[0073] Figure 4A 1 is a cross-sectional side view along the longitudinally oriented section line 100 or along the plane 110 extending from the toe portion 251 of the sole 250 to the heel portion 253 of the sole 250. The insole 300 can be a relatively thin insole base 310. Optionally, the insole 300 includes a flange 322 at least partially along the perimeter 320 of the insole base 310. During use, the insole 300 of the present footwear article 200 can be in direct contact with the user's foot. In the sole 250, the function of providing arch support is not primarily provided by the insole 300. In other words, the insole 300 can be set independently of the user's pronation problem (if any). This does not prevent the sole 300 from providing some support at the arch, this is only because the insole 300 is shaped to follow the surface contour of the sole of the foot. For example, the insole 300 of the present article of footwear 200 can have a substantially similar thickness 370 throughout the insole base. For example, a relatively soft material can be selected for the insole 300 of the present article of footwear. For example, the insole 300 can be shaped and sized to provide a surface 310 on which a user's foot can rest relatively comfortably. In some embodiments, the surface 310 of the insole 300 is the same as the inner surface of the sole 250. For example, a sock can optionally be used with the insole 300 of the present article of footwear 200.

[0074] The outsole 500 may include a three-dimensional (3D) component, for example, the outsole 500 includes a base layer 520 connecting multiple structures 540 with or without variable compression stiffness, which establishes an outer surface 514 and an outsole thickness 570. The outsole outer surface 514 is intended for direct contact with an external environment, such as the ground. To aid understanding and for simplicity, the term "outsole thickness" 570 will be used herein to refer to the thickness of the outsole 500. The outsole thickness 570 can be substantially similar across the entire outsole 500 of a piece of footwear 200. Different embodiments of the footwear article 200 or sole 250 can have an outsole thickness 570 that varies from embodiment to embodiment, or different embodiments of the footwear article 200 or sole 250 can have an outsole thickness 570 that varies in a piece of footwear.

[0075] Figure 4B and Figure 5A 2 is a cross-sectional view of a different exemplary embodiment of the outsole 250, showing an outsole 500 including multiple sections 600 with different physical properties, including bending stiffness, and a structure 540 with or without variable compression stiffness. For greater clarity, Figure 4B and Figure 5A The multiple regions in the outer sole 500 are respectively Figure 4C and Figure 5B 501 of the outsole 500. Each zone 600 extends longitudinally generally or substantially along the length 501 of the outsole (the length of the outsole can be taken as the longest length of the longitudinal axis running from the toe 251 of the outsole 250 to the heel 253 of the outsole 250). In the illustrated example, the outsole 500 includes three zones 600. For example, the outsole 500 includes a target zone 610 and a first zone 631 and a second zone 632 disposed on two lateral sides of the target zone 610. The first zone 631 is adjacent to the target zone 610 along the length 501 of the outsole 500. The second zone 632 is adjacent to the target zone 610 along the length 501 of the outsole 500. Each of these zones 600 can be substantially homogenous throughout the thickness 570 of the outsole 500.

[0076] In some embodiments, the curved feature 660 is integrated into the metamaterial structure of the outsole 500 so that the curved feature 660 is more subtle or less visible. In various embodiments, the curved line of the feature 600 is a series of spaces or valleys formed in the gaps 546 between the plurality of structures 540 of the outsole 500.

[0077] In various embodiments, the outsole 500 includes one or more flex features 660. For greater clarity, Figure 5A The curved feature 660 of the outsole 500 is shown in Figure 5B514. The flex feature 660 may define a curvilinear groove or slot, such as a cutout in the outer surface 514 of the outsole 500. The flex feature 660 may be a linear groove, an arcuate groove, or a curvilinear groove that defines a smaller outsole thickness relative to other portions of the outsole 500. Each of the one or more flex features 660 extends laterally, or in one or more orientations that are not parallel to the longitudinal direction or longitudinal axis 100. The flex feature 660 may extend across the entire width of the outsole 500, or the flex feature 660 may extend along a portion of the width of the outsole 500. Figure 5A and Figure 5B In the example shown, the outsole 500 includes three sections 600 separated by two curved features 660. As shown, the plurality of curved features 660 extend laterally and may be oriented differently relative to one another.

[0078] In various embodiments, the outsole 500 is elastic or compressible in multiple directions. In various embodiments, the outsole 500 is made of 3D printed pillars or flexible connectors 545. The outsole 500 may be provided with a metamaterial that is configured to relieve stress concentration and allow for larger cyclic loads. In various embodiments, the outsole 500 is provided with a target zone 610 that is characterized by having a lower bending stiffness than the corresponding bending stiffness of other non-target zones 630. For example, the target zone 610 is configured to have a lower stiffness than each of the first zone 631 and the second zone 632 or a higher flexibility than each of the first zone 631 and the second zone 632. For example, the outsole 500 is configured so that the elastic modulus of the target zone 610 is the lowest among all at least three zones 600. In various embodiments, the outsole 500 is provided with a target zone 610 characterized by having a lower bending stiffness and being composed of a plurality of structures 540 having a lower compression stiffness than the corresponding bending stiffness and compression stiffness of other non-target zones 630 .

[0079] The outsole 500 may have an outsole outer surface or outer face 514 that sets a mostly flat surface area for contact with the ground. The outer face 514 may be described as flat or substantially flat in this sense, ignoring irregularities caused by the properties of the metamaterial that constitutes the outsole 500. The outer face 514 is substantially planar or flat so that the foot muscles and leg muscles are in a condition similar to a barefoot state. The outsole outer surface 514 is sufficiently flat so that when the user stands still, the foot provides stable support for the user. For example, multiple regions 600 can set the outsole outer surface 514 in a coplanar manner. For example, in an example where the outsole 500 includes at least three regions 600 (a target region 610 and a first region 631 and a second region 632), all regions 600 set corresponding coplanar portions of the outsole outer surface 514.

[0080] The sole 250 may include a midsole 400 disposed between the insole 300 and the outsole 500. In some embodiments, the midsole 400 and the outsole 500 are disposed differently. Fig. 6A A bottom view of a midsole 400 according to some embodiments of the present application is shown, wherein multiple structures of the midsole 400 are connected to an outsole 500 (e.g., Figure 4B The multiple structures in the outer sole 500 shown are arranged differently. The midsole 400 includes an elastic body with multiple midsole areas 700 having different mechanical properties. For a clearer display, Figure 6B Different midsole regions 710, 720 are shown outlined in dashed lines.

[0081] For example, the midsole 400 may include a The main body 410 and the plurality of sections 700, each of the plurality of sections 700 is characterized by having a corresponding elastic , …、 Etc. The respective elasticity may vary depending on the amount of force absorption required by the respective zone 700, as will be further described below. The shape and dimensions of each zone 700 may vary accordingly, as will be further described below.

[0082] In some embodiments, one or more midsole regions 700 of midsole 400 may be molded or additively formed. In some embodiments, midsole 400 may be an assembly of separately manufactured components, any of which may be molded or additively formed. Figure 7 As schematically shown in the exploded view of , the midsole 400 may include a main body 410 , in which one or more cavities 420 are defined to accommodate one or more complementary inserts 430 .

[0083] In some embodiments, Figure 7As shown, the midsole 400 and the outsole 500 are manufactured separately before assembly. Figure 8 As shown in the exploded view of FIG. 4 , at least a portion of the midsole 400 (eg, the body 410 of the midsole 400 ) and the outsole 500 are molded or additively formed as an integral article in a continuous process.

[0084] Fig. 9 2 is a cross-sectional view of an example of a sole 250, which shows a structure 540 in the form of a support 545, with the support 545 defining a plurality of spaces 546 between the plurality of support 545 and / or defining a plurality of cavities 530 within a support 545. In some examples, as Fig. 10A As shown, the sole 250 may have a plurality of spaces 546 cut through the outer surface 514 of the sole 250. In some examples, such as Fig. 10B As shown, the sole 250 may have a plurality of cavities 530 opening at the inner surface 512 of the sole 250 .

[0085] In some embodiments, Fig.11A , Fig. 11B and Fig.12 As shown, the plurality of regions 600 of the compression structure 540 of different configurations may be characterized by having corresponding stiffness k 1 , k 2 , k 3 , k n Etc. The corresponding stiffness can be changed according to the required stiffness of the corresponding section 600. Multiple intervals 546 can be continuous and can be set by multiple convex structures 543. The convex structure 543 and the base layer 520 can together constitute the total thickness 370 of the sole 250 (for simplicity, the total thickness 370 is also referred to as "sole thickness" 370). The sole thickness 370 (for example, the total thickness or overall thickness of the sole 250) can be changed by introducing a cavity 530 or other additional bending features 660. Multiple intervals 546 can be set with different orientations and / or depths relative to the convex structure 543. For example, a depth corresponding to an interval 546 of substantially almost the entire sole thickness can be provided to obtain a lower stiffness. Alternatively, an interval 546 with a shallower depth (d) can be provided (compared to the length of the structure or the length of the convex structure). In some embodiments, some or all of the convex structures 543 can set a cavity 530 or an internal cavity with a depth (c). The depth and size of the plurality of cavities 530 may be variably set to help achieve variable stiffness settings on the sole 250 .

[0086] The size, shape, density, distribution pattern and / or material composition of the lug structure 543 and / or the interval 546 may vary from region to region, thereby forming a target region with maximum flexibility or minimum stiffness. The interval 546 is set by the lug structure 543 to set a bias path or a network with decreasing stiffness that is interconnected. Different settings of multiple structures (in this example, multiple lug structures 543) provide multiple stiffness gradients 560 in the sole 250 along different orientations. When the user walks, each of the multiple stiffness gradients 564 provides a bias that causes the COP line to dynamically shift toward the target region 610, that is, causes the COP line to dynamically shift toward the barefoot COP line set for the user.

[0087] Conventional insoles with lateral wedges tend to shift the user's weight on the foot laterally to the side of the foot. For a user with knee osteoarthritis, this lateral shift simply shifts pain from one area of ​​the knee to another area of ​​the knee. Furthermore, a user with early-stage knee osteoarthritis does not necessarily benefit from a lateral shift in the center of pressure. Such a user has a different load at the knee than a user with advanced knee osteoarthritis.

[0088] According to some embodiments, the present footwear article 200 includes a sole 250 that is configured to guide a user toward walking with a healthy center of pressure (COP) line 690, wherein the healthy COP line or target COP line 690 is obtained based on data of a healthy population and / or based on data of the user. In the present application, a healthy participant may refer to a subject who has no symptoms of knee osteoarthritis and is at a low risk of developing knee osteoarthritis. The sole 250 of the present footwear article 200 is configured such that the relative difference in stiffness of different regions 600 of the sole 250 promotes an unconscious weight shift so that the actual pressure line tends to be located in the target region 610. In various examples, the target region 610 is shaped and dimensioned based on center of pressure (COP) measurements obtained from a user walking barefoot, such as Fig.13 To distinguish the COP measurement results, the COP data used in the present application may be referred to as barefoot center of pressure (COP) data. For example, the target area 610 may be shaped and dimensioned to correspond to a barefoot COP area, where the barefoot COP area is set relative to a pressure centerline 690 measured by barefoot walking. In some examples, the barefoot COP line 690 may constitute the centerline of the target area 610.

[0089] Conventional wisdom teaches that the portion of the shoe that coincides with the COP line has the greatest stiffness because the portion of the sole that coincides with the COP line will need to bear the weight of the user. Therefore, the sole proposed in this application is counterintuitive because the target area 600 / 610 is set to have the lowest stiffness compared to other areas 610 of the sole 250.

[0090] Reference now FIG. 14A to FIG. 14D Exemplary methods of making various embodiments of the present sole 250 are described. FIG. 14A to FIG. 14D is a schematic diagram that relates the arrangement of the different portions of the sole 250 to a footprint or foot tracing.

[0091] Fig.14A Show that the foot tracing (e.g. Fig.13 Foot tracings shown) and plantar pressure distribution maps (e.g. Fig.13 Analysis combined with the plantar pressure distribution diagram shown). Fig.14A The diagram includes one or more areas 700 associated with strong impact 710 and one or more areas associated with weak impact 720. The arch 730 in this example represents an area with weak impact when walking barefoot. Fig.14A Also shown is a target COP line 690 relative to the foot tracing.

[0092] After determining the target COP line 690 and the plantar pressure distribution, the outsole 500 may be configured based on the correspondingly shaped multiple zones 600 with variable stiffness or variable flexibility and / or one or more flex features 660. For example, Fig. 14B As shown, the shape of the target zone 610 can coincide with the target COP line, wherein the plurality of non-target zones 630 are spaced apart from the target COP line. The outsole 500 can be configured to allow horizontal bending and / or diagonal bending, wherein at least one bending feature 660 intersects the high impact zone. In the example shown, the bending features include a forefoot bending line and a heel bending line.

[0093] The midsole 400 may be configured based on the determined high impact area 710 and low impact area 720 . Fig. 14C An example of a midsole 400 made of foam is shown with multiple inserts 430 within the body 410 to provide variable elasticity and variable compression characteristics within the midsole 400. In the example shown, the body 410 of the midsole corresponds to the low impact zone 720. The forefoot insert 431 of the midsole is shaped and sized to substantially correspond to the high impact zone 710 in the forefoot. The heel insert 432 of the midsole is shaped and sized to substantially correspond to the high impact zone 710 in the heel. The arch insert 433 of the midsole is shaped and sized to substantially correspond to the arch contour 730 of the foot.

[0094] Fig.14DAnother example of a midsole 400 made by 3D printing is shown to provide a functionally graded metamaterial structure with variable stiffness and variable compression characteristics (elasticity) within the midsole. The respective densities / stiffnesses of the plurality of sections 600 may be distributed according to a plantar pressure profile. The midsole 400 may be a 3D printed matrix of voxels or cells 440. The midsole 400 may include a plurality of sections 600 of a plurality of cells and / or a plurality of zones 700 with different force absorbencies. For example, the cells / voxels within the same zone may be characterized by having a common density, material, shape, and / or size so that the zone has similar force absorbency / elasticity. Different zones may be characterized by having at least one difference in the respective density, material, shape, and / or size of the cells / voxels so that the different zones have different force absorbency / elasticity. In general, the midsole is characterized by having variable stiffness / elasticity throughout the midsole. For example, a midsole may be 3D printed wherein a first volume element arrangement 441 corresponds to a high impact zone 710 , and wherein a different volume element arrangement 442 , 443 corresponds to a low impact zone 720 .

[0095] An article of footwear adapted to provide early intervention for knee osteoarthritis for a particular user is described below, but it will be appreciated that this does not preclude the sole 250 from being configured to be suitable for use by a plurality of users.

[0096] In some embodiments, the outsole 500 can be set without considering any pronation or supination problems. In some embodiments, the midsole 400 is set to provide greater flexibility and easy flexion of the entire midsole 440 and the outsole 500 along the target zone 610 or the target pressure centerline. In some embodiments, the outsole 500 is set to support the weight required by the user, while having the property of dynamically offsetting the user's walking COP line. The insole 300 is set based on the foot contour (or periphery in the plan view) and dimensions of the user's foot, thereby providing a shaped and sized insole 300 to accommodate the foot, for example, whether the foot is stationary or moving, the entire foot is on the insole 300. The material of the insole 300 is preferably thinner and flexible. The material of the insole 300 can be a material selected for comfort. Examples include, but are not limited to, leather, cotton, fleece, piled fabrics, and various natural and / or synthetic materials for barefoot comfort.

[0097] The midsole 400 is provided based on a plantar pressure profile 820 of a user's foot obtained in a normal manner of movement of the user during, for example, walking. Based on the plantar pressure profile 820, a topographical profile can be outlined for the midsole 400 according to a band of pressure values. For example, one or more sections 600 can be provided as high impact zones 710, and another one or more sections 600 can be provided as low impact zones 720. The midsole 400 is provided with greater force absorption / elasticity in one or more high impact zones 710. The midsole 400 is provided with lower force absorption / elasticity in one or more low impact zones 720. More than two impact levels can be provided for more levels of change in force absorption on the midsole 400. In a different embodiment without the midsole 400, the plurality of compression structures 540 on the outsole 500 assume the load attenuation characteristics of the midsole 400 as described above.

[0098] In some embodiments, different materials may be selected to provide different degrees of stiffness and / or force absorption in different sections 600. In a non-limiting example of midsole 400, high impact zone 710 is made of soft elastic rubber and low impact zone 720 is made of hard rubber. In some embodiments, different grades of similar materials may be selected to provide different degrees of stiffness in different sections 600. In a non-limiting example, midsole 400 includes high impact zone 710, which is made of ethylene vinyl acetate (EVA) foam with stronger force absorption than low impact zone 720. In some embodiments, midsole 400 may be made of materials of different densities, for example, high impact zone 710 made of low density foam and low impact zone 720 made of high density foam. In some embodiments, midsole 400 may be a 3D printed metamaterial having a less dense matrix structure in high impact zone 710 and a denser matrix structure in low impact zone 720.

[0099] In some embodiments, the midsole 400 may include a molded midsole body 410 made of a dense material. The midsole body 410 may define one or more cavities 420 corresponding to sections 600 having different degrees of stiffness (relative to the stiffness of the midsole body). Inserts 430 having different degrees of stiffness may be molded or 3D printed with complementary shapes and sizes to fit into corresponding cavities 420.

[0100] In some embodiments, the entire midsole 400 is molded, 3D printed, or a combination of molding and 3D printing to form a single product. In some embodiments, the midsole 400 and the outsole 500 are molded or 3D printed as a single product. In some embodiments, the midsole 400 and the outsole 500 are formed as a single product, which has a convex frame 550 to provide a partial shell that can accommodate the insole 300. In some embodiments, the outsole 500 includes a convex frame 550 to provide a partial shell that can accommodate the midsole 400.

[0101] The outsole 500 is set based on barefoot COP data obtained from the user or from other representative barefoot COP data sets. The term "barefoot COP line" 690 used herein refers to an imaginary line depicted relative to a footprint or foot tracing 810 to show the center of pressure that changes when placed on a specific foot during the movement of the subject / user. Depending on the conditions under which the COP data is collected, different tracings of the COP line can be collected for the same foot. For the purposes of this application, COP data is collected over a period of time while the subject / user is walking barefoot at a normal speed (e.g., as part of a gait analysis), and is referred to as barefoot COP to avoid confusion with COP data collected under different conditions (which can generate COP lines of different shapes). Alternatively, a barefoot COP line can be determined for a user based on COP data collected from a group of healthy subjects.

[0102] The target area 610 of the outsole 500 is set based on the barefoot COP line 690. Although for the sake of simplicity, the present application describes different embodiments using one foot as an example, the barefoot COP line 690 can be determined for each of the two feet of the user to solve the problem of gait asymmetry. Other parts of the non-target area in the outsole 500 can be named as one or more non-target areas 630.

[0103] The outsole 500 is a three-dimensional article having a uniform or substantially uniform outsole thickness 570 in a plurality of zones 600. The target zone 610 can be described as a specific width extending longitudinally from the toe 251 to the heel 253 of the sole 250, with the barefoot COP line 690 setting the centerline of the target zone 610.

[0104] In some embodiments, the outsole 500 is molded or 3D printed so that the target zone 610 has a lower target zone bending stiffness, and one or more non-target zones 630 each have a bending stiffness higher than the bending stiffness of the target zone 610. In some embodiments, the outsole 500 is made of foam and / or rubber or rubber-like materials. In some embodiments, the outsole 500 is a 3D printed metamaterial. In some embodiments, a plurality of compression structures 540 of the thickness 570 of the outsole 500 are molded or 3D printed, wherein the corresponding zones 600 have load attenuation characteristics. The term "metamaterial" as used herein refers to a network of interconnected or interconnected, multiple physical pillars or multiple components, which can move relative to each other and thus give the bulk material flexibility and / or elasticity. Different non-limiting examples of metamaterials are described above. The target zone 610 is connected to at least one non-target zone 630 at least at a plurality of gradients 560 or at a plurality of connection points 640 distributed longitudinally along the periphery 642 of the target zone. The multiple connections or multiple connection points 640 between the multiple physical structures or materials of the target area 610 and the one or more non-target areas 630 promote the transfer of stress to the lower stiffness target area. The present sole 250 is configured to inherently bias pressure toward the target area 610 so that the resulting effect is similar to or tends to barefoot walking, or tends to a target COP obtained based on data from healthy participants.

[0105] Fig.15 Test results are shown to compare the performance of the prototype of the present sole 250 with that of a conventional shoe. The results show that use of the prototype of the present sole 250 produced a measured COP line 682 that is closer to the target COP line 681 (barefoot COP line) than the COP line 683 reported for conventional footwear.

[0106] Different embodiments of the upper member 270 can be connected to the sole 250 to cooperatively form a footwear article 200 that can accommodate or be worn on the user's foot 150. The term footwear article 280 is used broadly in this application to refer to any item that can be secured to the foot, wherein the insole 300 is located under the foot. Examples of footwear articles 280 include, but are not limited to, shoes, slippers, boots, etc. The term "footwear article" as used herein may also refer to a foot support 282, for example, an article worn on the foot 150 and configured to support or support a portion of the foot or ankle. Fig.16 and Fig.17Non-limiting examples of footwear articles 200 in the form of a shoe and in the form of a foot brace are shown, respectively. In some examples, the upper portion 270 may include one or more fasteners 271, such as, but not limited to, Velcro fasteners. In some examples, the upper portion 270 may include a lining 272 therein for better fastening of the upper portion 270 to the skin of the foot 150. In some examples, the upper portion 270 may include a configurable metamaterial structural unit 273, which may be customized according to the needs of the user.

[0107] On the one hand, the present application describes different embodiments of footwear articles for providing early intervention of knee osteoarthritis to users. The footwear article includes a sole. The sole extends longitudinally along the length of the sole, in a longitudinal direction from the toe to the heel. The sole length is set to be at least the same as the length of the user's foot. The sole includes: an insole; and an outsole. The outsole includes: an outsole inner area; an outsole outer area; and an outsole body that sets the outsole thickness between the outsole inner area and the outsole outer area. The outsole body includes a plurality of elastically compressible sections. The plurality of sections include at least one non-target section and a target section. Each non-target section in at least one non-target section is characterized by having a corresponding local stiffness along a first direction. The target section is adjacent to at least one non-target section. The target section is characterized by having a target local stiffness. The target local stiffness along the first direction is lower than the corresponding local stiffness of any non-target section in at least one non-target section along the first direction. The target section extends longitudinally from the toe to the heel.

[0108] The target area can be set based on a barefoot center of pressure (COP) line. The COP line can be obtained based on barefoot walking data of healthy subjects. The COP line can be determined relative to barefoot walking. The COP line can be obtained based on barefoot walking data of a specific user.

[0109] The outer region of the outsole may include at least one curved feature extending transversely relative to the length of the sole. The at least one curved feature may be a groove having a groove depth that is less than the thickness of the outsole.

[0110] The sole may bend about a transverse axis defined by one of the at least one bending feature. Each of the plurality of zones may include a network of primary materials defining a compressible structure distributed therein. A corresponding bending stiffness of each of the plurality of zones may be related to a distribution density of the compressible lug structures. A corresponding bending stiffness of each of the plurality of zones may be related to a material stiffness of the primary material. A corresponding bending stiffness of each of the plurality of zones may be related to a thickness gradient of the base layer.

[0111] In some embodiments, the bending feature 660 may include one or more joint-type pivot features 668, such as Fig.18A and Fig.18B As described above with respect to different embodiments of the present application, the outsole 500 and the midsole 400 may be similarly arranged in the same section and in structure, or differently arranged in the same section and in structure. For the sake of brevity, it is understood that references to the outsole 500 in the present application may refer to an outsole integrated with the midsole 400, or to an outsole that is distinguishable from the midsole 400. To avoid confusion, the illustration of the sole 250 / outsole 500 has been simplified, and 18A to 18C Not all structural details are shown.

[0112] like Fig.18A As shown, the joint-type pivot feature 668 can be provided in the form of a spacer 660 that cuts through all or most of the sole thickness, with at least one joint 669 coupling the interface of the spacer 660. Fig.18B As shown in the exploded view of , at the interface of two adjacent sections 502 of the sole 250 / outsole 500, the joint-type pivot feature 668 may include one or more pairs of complementary joint elements (constituting one or more joints 669). Different types of joints 669 may be provided. Optionally, the joint-type pivot feature is provided with multiple degrees of freedom or a larger range of movement along at least one direction. For example, the joint may be a ball and socket joint or a linkage. Optionally, the joint element is shaped so that the joint element can be integrally and additively constructed with the additive manufacturing of the segment. The insole 300 may be provided as an interface between the foot and the rest of the segmented portion of the sole.

[0113] Fig.18C The upward view of the segmented portion shown, of the sole 250 shows that the joint-type pivot feature 668 can be arranged between a plurality of structures 540, to further promote the dynamic offset of the COP line towards the barefoot COP line 690, or further allow the foot to naturally carry out multi-segment bending, to simulate barefoot walking. The barefoot COP line 690 is arranged in the target area 610, but the target area 610 is not drawn here to avoid confusion. A plurality of structures 540 may include any one or any combination of two or more of the following: a bump structure, a pillar, a cavity and an interval, which are arranged and / or set to promote the dynamic offset of the COP line towards the barefoot COP line or towards the target area 610. As described above with respect to different embodiments, the bump structure 543 may include or may not include the cavity 530 set in each bump structure 543.

[0114] The plurality of segments 502 may correspond to different zones in the plurality of zones 600. Each segment 502 may constitute a portion of the plurality of zones 600. The multi-segment sole 250 may be configured such that the barefoot COP line 690 lies entirely or substantially along a jointed pivot feature extending from the toe 251 to the heel 253 of the sole 250. Any of the plurality of jointed pivot features (also referred to as flexion intervals) 668 may be positioned / oriented in the sole 250 to follow the orientation or movement of one or a combination of the bone joints of the foot. In some examples, the entire outsole 500 is comprised of a plurality of segments 502 interconnected by joint-type pivot features 668, wherein each segment 502 includes a plurality of structures 540 having a stiffness gradient 560 that facilitates dynamic shifting of the COP line toward a barefoot COP line 690, wherein the barefoot COP line 690 substantially coincides or completely coincides with one or more joint-type pivot features 668.

[0115] On the other hand, the sole can be set based on a method, the method comprising: (i) determining the position of the user's pressure centerline relative to the outer area of ​​the sole, the pressure centerline being obtained based on barefoot walking data; (ii) setting a target area so that the pressure centerline corresponds to the centerline of the target area in the longitudinal direction; and (iii) setting the stiffness of the target area and the local stiffness of each of the plurality of non-target areas. The barefoot walking can be performed by a group of healthy participants or users. The users can be people with early knee osteoarthritis or at risk of knee osteoarthritis.

[0116] The thickness of the insole can be set independently of the plantar pressure distribution of the foot. The insole can include a heel cup. The heel cup can be composed of one or more flanges, wherein the one or more flanges extend at least partially along the periphery of the insole base, at or near the heel region. The heel cup beneficially provides improved fit, better stability, and more uniform plantar pressure distribution.

[0117] In one aspect, the present application discloses different embodiments of a footwear article for providing early intervention of knee osteoarthritis for a user, the user having a barefoot center of pressure (COP) line that can be measured for the user in barefoot walking, the footwear article comprising: an upper portion; and a sole. The sole has an outer surface and an inner surface, and the sole is coupled to the upper portion so that the inner surface and the upper portion can cooperatively accommodate the user's foot. The sole includes a plurality of structures. The plurality of structures are interconnected and partially spaced apart to set a spacing distribution, thereby allowing the foot to move freely during movement. The plurality of structures are variably arranged on a plurality of regions of the sole to provide a plurality of regions with corresponding stiffnesses that vary between the plurality of regions, thereby providing local support and absorbing forces. The plurality of regions are three-dimensional. The plurality of regions include a target region, the target region being characterized by having a stiffness lower than any corresponding stiffness of any other region of the plurality of regions. The target region is shaped and positioned on the sole to coincide with a barefoot COP line or a target average COP line derived from data of a group of healthy participants. At least the outer surface of the target zone is planar relative to the inner surface of the sole.

[0118] The plurality of structures are characterized by having a stiffness gradient that decreases toward the target region. Each region is characterized by having a local stiffness. The target region may form a continuous region that is characterized by having a local stiffness that is lower than the local stiffness of any other region in the plurality of regions.

[0119] A footwear article according to any of the above, wherein the sole comprises an insole and an outsole, the insole providing an inner surface and the outsole providing an outer surface, and wherein a plurality of structures are arranged on the outsole. The footwear article may also comprise a midsole, wherein the midsole is arranged between the insole and the outsole. The midsole and the outsole may be made with a plurality of structures and / or a plurality of structures and / or a plurality of cavities arranged differently in a plurality of cavities. The midsole and the outsole may be made with a plurality of structures and / or a plurality of structures and / or a plurality of cavities arranged similarly in a plurality of cavities. The midsole and the outsole may be additively made as an integral component.

[0120] The insole may be partially shaped with a flange along a perimeter of the heel region, and wherein the insole is dimensioned according to a contour of the foot under non-weight bearing conditions.

[0121] A footwear article according to any of the above items, wherein the sole is set based on a method, the method comprising: determining the position of the user's pressure center line relative to the sole, the target pressure center line being obtained based on data of the user walking barefoot or based on data of a group of healthy people without symptoms or risk factors of knee osteoarthritis; setting a target zone so that the pressure center line corresponds to the center line of the target zone; and setting the stiffness of the target zone and the corresponding stiffness of other zones in the plurality of zones to allow the user's moving COP to dynamically shift toward the target COP line of the footwear article.

[0122] All examples described herein, whether devices, methods, materials or products, are presented for the purpose of illustration and aiding understanding, and are not intended to be limiting or exhaustive. Those skilled in the art may make modifications without departing from the scope of the claims of the present invention.

Claims

1. A footwear article for providing early intervention of knee osteoarthritis for a user, the user having a pressure centerline measurable relative to the user while moving and a barefoot pressure centerline measurable relative to the user while walking barefoot, the footwear article include: upper part; as well as a sole having an outer surface and an inner surface, the sole being coupled to the upper portion so that the inner surface and the upper portion can cooperatively accommodate the user's foot, wherein the sole is comprised of a plurality of structures, the plurality of structures being at least partially spaced apart, the plurality of structures having different arrangements at a plurality of regions of the sole to provide the plurality of regions with respective stiffnesses varying between the plurality of regions, the plurality of regions being three-dimensional, and wherein the plurality of zones includes a target zone characterized by having a stiffness lower than any corresponding stiffness of any other zone of the plurality of zones, And wherein the target zone is shaped and positioned on the sole to coincide with the barefoot pressure centerline of the user.

2. The article of footwear according to claim 1, wherein the barefoot pressure centerline is set based on data of the user walking barefoot.

3. The article of footwear of claim 1 or 2, wherein the barefoot pressure centerline is set based on data from a group of healthy individuals with no known symptoms or risk factors for knee osteoarthritis.

4. A footwear article according to any one of claims 1 to 3, wherein different arrangements of the multiple structures provide multiple stiffness gradients in the sole along different orientations, and each of the multiple stiffness gradients forces the pressure centerline to dynamically shift toward the barefoot pressure centerline.

5. The footwear article according to any one of claims 1 to 4, wherein the plurality of stiffness gradients are arranged to decrease stiffness along different directions along the plurality of stiffness gradients towards the target region.

6. The article of footwear according to any one of claims 1 to 5, wherein the plurality of structures allow the foot to move freely during movement, and wherein the plurality of zones provide force absorption and localized support for the foot.

7. The footwear article according to any one of claims 1 to 6, wherein each of the plurality of zones is characterized by having a local stiffness, and wherein the target zone constitutes a continuous zone, the continuous zone being characterized by having a local stiffness lower than the local stiffness of any other zone of the plurality of zones.

8. The article of footwear according to any one of claims 1 to 7, wherein the plurality of structures comprises a plurality of lug structures, and wherein adjacent lug structures in the plurality of lug structures are spaced apart to define a spaced network.

9. The article of footwear of claim 8, wherein the sole comprises a base layer having the plurality of structures protruding from the base layer, and wherein a sole thickness of the sole is comprised of a thickness of the base layer and a length of one of the plurality of structures.

10. The article of footwear of claim 9, wherein within any one of the plurality of sections, the plurality of structures are disposed approximately relative to their lengths.

11. The article of footwear according to any one of claims 1 to 10, wherein each of the plurality of regions is made of a resilient foam and / or an additively molded meta-material structure.

12. The article of footwear according to claim 11, wherein at least two adjacent sections of the plurality of sections are made as removable pieces of the resilient foam and / or additively molded meta-material structures having different stiffnesses.

13. The article of footwear according to claim 12, wherein the at least two adjacent sections of the plurality of sections are formed with complementary shapes.

14. The article of footwear according to any one of claims 1 to 13, wherein at least two adjacent zones of the plurality of zones include differently arranged structures, and wherein the at least two adjacent zones of the plurality of zones are characterized by having different stiffnesses.

15. The article of footwear according to claim 14, wherein the at least two adjacent zones of the plurality of zones include different densities of the plurality of structures.

16. The article of footwear according to claim 14 or 15, wherein the at least two adjacent ones of the plurality of zones include differently shaped ones of the plurality of structures.

17. The article of footwear according to any one of claims 14 to 16, wherein the at least two adjacent ones of the plurality of zones include differently sized ones of the plurality of structures.

18. The article of footwear according to any one of claims 14 to 17, wherein the at least two adjacent sections of the plurality of sections comprise a plurality of structures made with different material stiffnesses.

19. A footwear article according to any one of claims 1 to 4, wherein each of the plurality of zones comprises a network of a main material having a compressible bulge structure distributed therein, and wherein the corresponding stiffness of each of the plurality of zones is related to the distribution density of the compressible bulge structure.

20. The article of footwear according to any one of claims 1 to 13, wherein the sole comprises a base layer defining the inner surface of the sole, the plurality of structures within any one of the plurality of regions being similarly arranged throughout the sole thickness of the sole.

21. The article of footwear of claim 20, wherein each of the plurality of regions is characterized by having a bending stiffness that is related to a thickness gradient of the base layer to which the plurality of structures are coupled.

22. The article of footwear according to any one of claims 1 to 21, wherein the sole comprises an insole and an outsole, the insole providing the inner side and the outsole providing the outer side, and wherein the plurality of structures are disposed on the outsole.

23. The article of footwear of claim 22, further comprising a midsole disposed between the insole and the outsole.

24. The article of footwear according to claim 23, wherein the midsole and the outsole are made with several structures and / or several cavities arranged differently among the plurality of structures and / or plurality of cavities.

25. The article of footwear according to claim 23 or 24, wherein the midsole and the outsole are made with several structures and / or several cavities of the plurality of structures and / or the plurality of cavities arranged similarly.

26. The article of footwear according to any one of claims 23 to 25, wherein the midsole and the outsole are additively manufactured as a one-piece component.

27. The article of footwear according to any one of claims 1 to 26, wherein the sole comprises at least two sections coupled by a joint.

28. The article of footwear of claim 27, wherein the joint has multiple degrees of freedom.

29. The article of footwear according to any one of claims 1 to 28, wherein the sole is provided based on a method, the method include: Determine the position of the pressure centerline of the user relative to the sole, wherein the pressure centerline is obtained based on either or both of (i) data of the user walking barefoot and (ii) data of a group of healthy people; setting the target section so that the pressure centerline corresponds to a centerline of the target section; and A stiffness of the target section and corresponding stiffnesses of other sections of the plurality of sections are set.

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