Knee brace

Abstract

The knee orthosis of the present invention includes a femoral cuff configured to engage with the upper leg of the wearer, a tibial cuff configured to engage with the lower leg of the wearer, and a hinge that pivotably connects the femoral cuff to the tibial cuff. The hinge has a femoral portion and a tibial portion, which engage with each other and include a shell configured to pivot relative to each other about a center of rotation. One shell includes an engagement surface facing a complementary engagement surface on the other shell. The engagement surface and the complementary engagement surface each have a shape corresponding to a part of an ellipsoid defined by a major axis extending in the sagittal plane, a minor axis perpendicular to the major axis, and the length of the ellipsoid along the major axis being longer than the length along the minor axis, and rotation around the major axis.

Description

Cross - reference to related applications

[0001] This application claims priority to U.S. Patent Application No. 63 / 501,798, filed May 12, 2023, the entire content of which is incorporated herein by reference.

Technical Field

[0002] This disclosure generally relates to knee braces and / or knee orthoses.

Background Art

[0003] A knee orthosis is an externally worn device used to affect the structural and functional characteristics of the neuromuscular and skeletal systems. A knee orthosis is a brace that extends above and below the knee joint and is generally worn to support or align the knee during flexion. In the case of a disease or injury that affects the ligaments or cartilage of the knee, the knee orthosis can stabilize the knee by substituting or assisting the function of the ligaments or cartilage of the damaged or impaired knee. For example, by using a knee brace, the pressure from a diseased knee joint site such as arthritis or osteoarthritis can be relieved by realigning the knee joint into valgus or varus. In this way, the knee orthosis can help reduce the pain of osteoarthritis. When used appropriately, a knee brace can also assist the wearer in remaining active by improving the position and movement of the knee and reducing pain.

[0004] Knee orthoses have been developed to follow the natural center of rotation of the knee, which changes position during knee flexion. In other words, the position of the center of rotation of the knee changes with knee flexion, and the knee orthosis has been developed to follow and support the natural movement of the knee during flexion.

[0005] However, despite previous efforts, there is room for improvement in the field of knee orthoses.

Summary of the Invention

[0006] It should be understood that any or all configurations, aspects, or embodiments described herein may be used or combined with any other configurations or embodiments described herein, unless otherwise specified.

[0007] According to one embodiment, a knee orthosis is provided comprising a femoral cuff configured to engage with the upper leg of the wearer, a tibial cuff configured to engage with the lower leg of the wearer, and a hinge that pivotably connects the femoral cuff to the tibial cuff, wherein the hinge has a femoral portion connected to the femoral cuff and a tibial portion connected to the tibial cuff, the femoral portion and the tibial portion engaging with each other and each shell configured to pivotably move relative to each other about a center of rotation, the first shell of which includes an engaging surface facing a complementary engaging surface on the second shell of which, the engaging surface and the complementary engaging surface each have a shape corresponding to a part of an ellipsoid defined by a major axis extending in the sagittal plane, a minor axis perpendicular to the major axis, and the length of the ellipsoid along the major axis being longer than the length along the minor axis, and rotation about the major axis.

[0008] Furthermore, the knee braces defined above and described herein may include any of the following components, in whole or in part, and in any combination thereof:

[0009] In some implementations, the long axis corresponds to the anterior-posterior axis, and the long axis is positioned in the sagittal plane at a predetermined angle to the frontal plane which is perpendicular to the sagittal plane.

[0010] In some implementations, the given angle is between 40 and 80 degrees.

[0011] In some implementations, the length of the ellipsoid along the minor axis is determined based on the morphological characteristics of the wearer's knee.

[0012] In some implementations, the morphological feature is the width of the wearer's knee.

[0013] In some implementations, the length of the ellipsoid along the major axis is longer than the length of the ellipsoid along the minor axis by an amount corresponding to the anterior-posterior shift of the knee's center of rotation.

[0014] In some implementations, there is a first interference between shells in the intermediate bending point configuration of the hinge, a second interference between shells in the starting point bending configuration, and a third interference between shells in the ending point bending configuration, with the first interference being smaller than at least one of the second or third interferences.

[0015] In some implementations, either the femoral or tibial portion of the hinge has at least one guide slot defined within the corresponding shell, and the other femoral or tibial portion has at least one pin extending within the at least one guide slot that guides the pivot of the femoral and tibial portions relative to each other, the at least one pin defining an axis that intersects the center of rotation of the wearer's knee.

[0016] In some implementations, the hinge includes two or three guide slots and two or three pins, the two or three guide slots being located on the femoral portion, the tibial portion, or a combination thereof, and the two or three pins being located on the femoral portion, the tibial portion, or a combination thereof.

[0017] In some implementations, the femoral portion of the hinge has at least one guide slot and at least one pin, and the tibial portion of the hinge has at least one guide slot and at least one pin.

[0018] In some implementations, the center of rotation is the instantaneous center of rotation in a given bending configuration of the hinge, and the instantaneous center of rotation moves along the trajectory when the hinge is bent.

[0019] In some implementations, the center of rotation is the instantaneous center of rotation in a given bending configuration of the hinge, the instantaneous center of rotation moves along a trajectory when the hinge is bent, and the axis of at least one pin intersects the instantaneous center of rotation regardless of the bending configuration of the hinge.

[0020] In some implementations, the trajectory is contained within the sagittal plane.

[0021] In another embodiment, a knee orthosis is also provided, comprising a femoral cuff configured to engage with the upper leg of the wearer, a tibial cuff configured to engage with the lower leg of the wearer, and a hinge that pivotably connects the femoral cuff to the tibial cuff, the hinge having a femoral portion connected to the femoral cuff and a tibial portion connected to the tibial cuff, the femoral portion and the tibial portion engaging with each other and comprising corresponding shells configured to pivot toward each other about a center of rotation, either the femoral portion or the tibial portion having at least one guide slot defined within the corresponding shell, the other femoral portion or the tibial portion having at least one pin extending from the shell of the other and housed within at least one guide slot that guides the pivot of the femoral portion and the tibial portion toward each other, the at least one pin defining a pin axis intersecting the center of rotation of the wearer's knee.

[0022] Furthermore, the knee braces defined above and described herein may include any of the following components, in whole or in part, and in any combination thereof:

[0023] In some implementations, the center of rotation is the instantaneous center of rotation in a given bending configuration of the hinge, the instantaneous center of rotation moves along the trajectory when the hinge is bent, and the pin axis intersects the instantaneous center of rotation regardless of the bending configuration of the hinge.

[0024] In some implementations, the trajectory is contained within the sagittal plane.

[0025] In some implementations, the shell has a shape corresponding to a portion of an ellipsoid defined by a major axis line extending in the sagittal plane, a minor axis line orthogonal to the major axis line, the length of the ellipsoid along the major axis line being longer than the length along the minor axis line, and rotation about the major axis line.

[0026] In some implementations, the major axis line corresponds to the anteroposterior axis line and is disposed in the sagittal plane at a predetermined angle with respect to the frontal plane orthogonal to the sagittal plane.

[0027] In some implementations, the predetermined angle is between 40 degrees and 80 degrees.

[0028] In some implementations, the length of the ellipsoid along the minor axis line corresponds to the morphological characteristics of the wearer's knee.

[0029] In some implementations, the morphological characteristic is the width of the wearer's knee.

[0030] In some implementations, the length of the ellipsoid along the major axis line is longer than the length of the ellipsoid along the minor axis line by an amount corresponding to the anteroposterior shift of the center of rotation of the knee.

[0031] In some implementations, there is a first interference between the shells in the intermediate flexion point configuration of the hinge, a second interference between the shells in the starting point flexion configuration, and a third interference between the shells in the end point flexion configuration, and the first interference is less than at least either the second interference or the third interference.

[0032] Further details regarding these and other aspects of the subject matter of this application will become apparent from the detailed description and drawings included below.

Brief Description of the Drawings

[0033] [Figure 1] FIG. 1A is a top view of a tibial plateau showing the instantaneous flexion axis line at 10-degree intervals in the range of knee flexion angles from 0° to 120°. FIG. 1B is an isometric view of the tibial plateau of FIG. 1A. [Figure 2]This is an isometric view of a knee brace relating to one implementation form of this technology. [Figure 3A] Figure 2 shows isometric views of the lateral and medial hinges of the knee brace. [Figure 3B] Figure 3A is a front view of the hinge. [Figure 3C] Figure 3A is a side view of the hinge. [Figure 4A] This is an isometric view of the thigh-side portion of the hinge in Figure 3A. [Figure 4B] This is a top view of the thigh portion of Figure 4A. [Figure 4C] This is a front view of the thigh portion of Figure 4A. [Figure 4D] This is a lateral view of the lateral thigh portion of Figure 4A. [Figure 4E] This is a lateral view of the medial thigh portion of Figure 4A. [Figure 5A] This is an isometric view of the tibial portion of the hinge in Figure 3A. [Figure 5B] Figure 5A is a top view of the tibial portion. [Figure 5C] Figure 5A is a frontal view of the tibial portion. [Figure 5D] Figure 5A is a lateral view of the medial tibial portion. [Figure 5E] Figure 5A is a lateral view of the lateral tibial portion. [Figure 6A] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge, each having different combinations and permutations of two pins and two slots. [Figure 6B] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge, each having different combinations and permutations of two pins and two slots. [Figure 6C] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge having yet another combination and permutation of two pins and two slots. [Figure 6D] This is an exemplary side view of a hinge configuration showing both the femoral and tibial portions of each hinge configuration having different combinations and permutations of three pins and three slots. [Figure 6E] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge configuration having different combinations and permutations of three pins and three slots. [Figure 6F] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge configuration having yet another combination and permutation of three pins and three slots. [Figure 6G] This is a side view of an exemplary hinge configuration showing both the femoral and tibial portions of each hinge configuration having yet another combination and permutation of three pins and three slots. [Figure 7A] Figure 3A is a side view of the hinge in a 10° flexion configuration, with the thigh portion shown in perspective. [Figure 7B] Figure 7A is a side view of the hinge in a 60° bent configuration. [Figure 7C] Figure 7A is a side view of the hinge in a 120° bend configuration. [Figure 8A] Figure 3A is a top view of the lateral hinge in a 10° flexion configuration, where the pin axis converges to the instantaneous center of rotation of the knee. [Figure 8B] This is a side view of the outer hinge in Figure 8A. [Figure 8C] Figure 3A is a top view of the lateral hinge in a 60° flexion configuration, where the pin axis converges to the instantaneous center of rotation of the knee. [Figure 8D] Figure 8C is a side view of the outer hinge. [Figure 8E] Figure 3A is a top view of the lateral hinge in a 120° flexion configuration, where the pin axis converges to the instantaneous center of rotation of the knee. [Figure 8F] Figure 8E is a side view of the outer hinge. [Figure 9A] These are isometric views of the sagittal, frontal, and cross-sectional planes at the initial position. [Figure 9B] This is an isometric view of the plane in Figure 9A translated to the intermediate bending point. [Figure 9C] This is an isometric view of the major and minor axes corresponding to the axes defined by the plane in Figure 9B. [Figure 9D]This is an isometric view of an ellipsoid defined by rotation around the major axis and minor axis of Figure 9C. [Figure 10A] Figure 9D is an isometric view of an ellipsoid with transparency, centered on the center of rotation of the knee on the tibial plateau. [Figure 10B] This is an isometric view of a portion of the ellipsoid defining the tibial plateau and hinge shell; [Figure 10C] This is an isometric view showing the tibial plateau and hinge shell, with the instantaneous flexion axis projected onto the shell. [Figure 11A] This is a top view of a circle used to define an ellipsoid whose center corresponds to the COR when bent at 0°. [Figure 11B] This is a top view showing circles with centers corresponding to 5° increments of bending angle. [Figure 11C] This is an isometric view of the shell defined as part of the ellipsoid obtained from the circle in Figure 11B. [Figure 12A] This is a top view of a circle used to define an ellipsoid with a center corresponding to the COR when bent at 0°, and another circle with a center corresponding to the COR when bent at 120°. [Figure 12B] This is an enlarged view of region 12B in Figure 12A. [Figure 12C] This is an isometric view of the ellipsoid obtained from the circle in Figure 12A. [Modes for carrying out the invention]

[0034] Please refer to the attached drawing.

[0035] The following disclosure describes a knee brace 20, which is generally an embodiment of the Art. It should be clearly understood that the knee brace 20 is merely an embodiment of the Art. The following description is intended to be merely a description of a physical embodiment of the Art. This specification is not intended to define the scope or boundaries of the Art. In some cases, embodiments that may be useful as modifications to the knee brace 20 are shown below, but these are for illustrative purposes only and do not define the scope or boundaries of the Art. These modifications are not exhaustive, and as those skilled in the art will understand, other modifications are possible. Furthermore, where no modifications are shown here, i.e., where no examples of modifications are described, it should not be interpreted that modifications are impossible, and / or that what is described is the only physical means of embodying that element of the Art. As those skilled in the art will understand, this is not usually the case.

[0036] Referring to Figures 1A-1B, the knee is one of the most complex joints in the human body, with five degrees of freedom: (i) flexion / extension rotation, (ii) adduction / abduction rotation, (iii) external / internal rotation, (iv) anterior-posterior translation, and (v) vertical translation. For example, the center of rotation 10 of the axis can be determined at each 5° increment from 0° to 120° of knee flexion angle, and the positions of the lateral and medial endpoints defining the orientation of the axis at each increment can be determined. The instantaneous center of rotation (COR) 10 moves along a trajectory 10a contained within the sagittal plane 12 during knee flexion. In other words, the biomechanical COR 10 of the knee translates along the trajectory 10a along the anterior-posterior axis 12a and the vertical axis 14a (projected in and out of the sheet including Figure 1A) extending within the sagittal plane 12. In the following description, we refer to the sagittal plane 12, the frontal plane 14, and the transverse plane 16 (i.e., included in the sheet containing Figure 1A), all of which are orthogonal to each other. More specifically, the anterior-posterior axis 12a lies on the intersection of the sagittal plane 12 and the transverse plane 16. The medial-lateral axis 16a lies on the intersection of the frontal plane 14 and the transverse plane 16. The COR 10 of the knee is at the center of the instantaneous flexion axis 18, which extends between the lateral condylar center 18a and the medial condylar center 18b.

[0037] The knee orthosis 20 will be described with reference to Figures 2 to 9C. As will be clear from the following description, the knee orthosis 20 has a configuration designed to restrain the knee during knee flexion, and prevents the knee from moving outside a predetermined range of motion by allowing rotational and translational movements corresponding to the instantaneous flexion angle of the knee. In other words, the knee orthosis 20 has a configuration designed to closely follow the COR 10 of the knee.

[0038] Referring here to Figure 2, the knee orthosis 20 has a femoral cuff 22 configured to engage with the femur of the wearer of the knee orthosis 20, a tibial cuff 24 configured to engage with the tibia of the wearer, and hinges 30a and 30b that pivotably connect the femoral cuff 22 to the tibial cuff 24. The hinges 30a and 30b will be described later. However, as described herein, the hinges 30a and 30b are formed by complementary shells having ellipsoidal engagement surfaces. The lateral hinge 30a and the medial hinge 30b are asymmetric with respect to the sagittal plane 12, thereby the contours of each of the opposing hinges and the shapes of the slots defined in each of the hinges (described later) are not symmetric with respect to the sagittal plane 12. The term “asymmetric” as used herein with respect to the lateral hinge 30a and the medial hinge 30b should be understood to be defined in this way. However, it should be understood that while certain surfaces (such as the curvature of the shell) may be symmetrical with respect to the sagittal plane 12, the lateral hinge 30a and medial hinge 30b may be asymmetrical. The asymmetry of the lateral hinge 30a and medial hinge 30b allows the knee to perform a selected flexion movement when the knee brace 20 is worn. This selected knee movement may, in some cases, correspond to the natural biomechanical movement of the knee. However, in other cases, it may be desirable to select a movement controlled by the knee brace 20 that deviates from the natural movement of the knee.

[0039] The knee orthosis 20 described herein, more specifically its hinges 30a and 30b, allows for five degrees of freedom of movement excluding medial-lateral displacement, and further allows for control of the amplitude of movement in each of these degrees of freedom according to the knee flexion angle. That is, the expected range across the entire flexion range in each degree of freedom of the tibia relative to the femur may be as follows: adduction (-)-abduction (+) from 0 to 7.5°, external rotation (-)-internal rotation (+) from 0 to 15°, medial (-)-lateral (+) translation from -5 mm to +5 mm, anterior (+)-posterior (-) translation from 0 to 15 mm, and proximal (+)-distal (-) translation from -5 mm to 10 mm.

[0040] Continuing to refer to Figure 2, the femoral cuff 22 and tibial cuff 24 of the knee orthosis 20 can be sized and / or adjusted to fit the wearer's morphological features. The cuffs 22 and 24 may be manufactured using injection molding techniques and may be manufactured in different sizes and configurations. In some implementations, the cuffs 22 and 24 are fabricated using additive manufacturing techniques based on a model of the wearer's knee obtained from scanning and / or measuring the wearer's knee. Such implementations allow the femoral cuff 22 and tibial cuff 24 to be tailored to the wearer, potentially improving wearer comfort.

[0041] Referring further to Figure 2, the hinges 30a and 30b include an outer hinge 30a and an inner hinge 30b. The hinges 30a and 30b have similar structure and characteristics and will be described together in the following description unless otherwise specified. The knee brace 20 may also be a unilateral configuration, including only one of the inner or outer hinges. The hinges 30a and 30b are provided as separate components from the cuffs 22 and 24, but may also have a portion formed integrally with the cuffs 22 and 24.

[0042] Referring to Figures 3A to 3C, each of the hinges 30a and 30b has a femoral portion 32 configured to connect to the femoral cuff 22 and a tibial portion 34 configured to connect to the tibial cuff 24. The femoral portion 32 and the tibial portion 34 are connected to the corresponding cuffs 22 and 24 by appropriate attachment means, which may include, for example, fasteners, welding, joining, and / or adhesives. By providing the hinges 30a and 30b as components separate from the cuffs 22 and 24, it is possible to combine appropriately sized cuffs 22 and 24 or custom-made cuffs 22 and 24 with hinges 30a and 30b, which may be manufactured using other manufacturing techniques such as machining or additive manufacturing, or using materials different from those of the cuffs 22 and 24. The hinges 30a and 30b allow the femoral cuff 22 and the tibial cuff 24 to pivot relative to each other during knee flexion. More specifically, hinges 30a and 30b are configured to allow rollback and screw-home movement of the femur during knee flexion and extension.

[0043] Referring to Figures 4A to 4E, the femoral portions 32 of the hinges 30a and 30b are shown. In the illustrated embodiment, the femoral portion 32 has spaced-apart medial shells 40a and lateral shells 40b on both the medial and lateral sides. However, it should be understood that alternatively, the femoral portion 32 may have only one shell, which is housed in a gap defined between two shells that form part of the tibial portion 34. In other words, in this alternative embodiment, each hinge is substantially inverted relative to hinges 30a and 30b as shown. However, in the embodiment of Figures 4A to 4E, the medial shell 40a is located closer to the wearer's knee, and the lateral shell 40b is located further away from the wearer's knee. The shells 40a and 40b extend parallel to each other and are offset to define a gap 40c (Figure 4C) between them.

[0044] The engagement surfaces 41 (see Figure 4B) of the shells 40a, 40b (i.e., the thigh shells) have a shape corresponding to a portion of the ellipsoid 60 (Figure 8D), a feature that will be described later. The engagement surfaces 41 of the shells 40a, 40b are adapted to engage with other components of the hinges 30a, 30b. The engagement surfaces 41 may be polished or surface-finished to reduce friction or wear when engaging with other components of the hinges 30a, 30b. In some implementations, the engagement surfaces 41 may be defined by consumable wear material provided on the shells 40a, 40b to limit wear on the shells 40a, 40b. The shells 40a, 40b further define holes 42a, 42b, 42c adapted to accommodate corresponding pins 44a, 44b, 44c (Figure 2). Each pin 44a, 44b, 44c extends into the gap 40c. Pins 44a, 44b, and 44c may be provided in the form of fasteners such as screws, rivets, or bolts and nuts. Alternatively, pins 44a, 44b, and 44c may be integrally formed with the femoral shell or the tibial shell. Pins 44a, 44b, and 44c each define pin axes 46a, 46b, and 46c (see Figures 7A to 7F), each pin axis extending longitudinally through the center of the corresponding pin.

[0045] Referring to Figures 5A to 5E, the tibial portions 34 of the hinges 30a and 30b are shown. The tibial portions 34 have shells 50a and 50b (i.e., tibial shells) fitted to be inserted into the gap 40c. The shells 50a and 50b define engaging surfaces 52 having a shape corresponding to a portion of the ellipsoid 60 (Figure 8D), similar to the engaging surfaces 41 of the femoral shells 40a and 40b, a feature that will be described later. The elliptical engaging surfaces 52 of the tibial shells 50a and 50b are fitted to slide on the complementary elliptical engaging surfaces 41 of the medial shell 40a and lateral shell 40b of the femoral portion 32. The engaging surfaces 52 may also be polished or surface-finished to reduce friction or wear when engaging with the engaging surfaces 41. The engaging surfaces 52 may also be defined in some implementations by consumable abrasive material provided on the shells 50a, 50b to limit wear of the shells 50a, 50b. The shells 50a, 50b further define guide slots 54a, 54b, 54c, which are adapted to house one of the corresponding pins 44a, 44b, 44c. The guide slots 54a, 54b, 54c are adapted to guide the pivot of the femoral portion 32 and the tibial portion 34 relative to each other during flexion of the knee orthosis 20. The guide slots 54a, 54b, 54c are defined over the entire flexion range of the knee orthosis 20 by tracking projections along the instantaneous flexion axis 18 on the ellipsoid 60.

[0046] More specifically, the geometric shape of the guide slots is selected such that, as the knee brace moves through its full range of flexion, the relative motion between the guide slot and the pin at each of several points along the range of motion generates a predetermined rotation around a virtual flexion axis, resulting in the desired movement of the knee (i.e., the five degrees of freedom of the femur relative to the tibia). In other words, the relative position of each pin within each slot at a given moment defines the instantaneous axis of rotation. At each of several points along the path of motion, as the knee brace moves through its full range of flexion, there exists a corresponding instantaneous axis of rotation defined by the slot. Thus, these several points correspond to several flexion angles of the knee brace at each of the several points as the hinge pivots through the full range of flexion of the knee brace. The slots in the hinge are designed such that their instantaneous axes of rotation and the corresponding flexion angles collectively define the instantaneous flexion axis of the desired movement of the knee. Therefore, the selected relative position of the pin axis is projected onto the ellipsoidal shell around each corresponding rotation axis and flexion angle of the desired knee movement, allowing the movement path of the guide slot to be traced.

[0047] In this implementation, the side wall of the tibial portion 34 defining the guide slots 54a, 54b, and 54c extends parallel to the corresponding axes 46a, 46b, and 46c. In other implementations, the side wall may have a convex arc shape, allowing the pins 44a, 44b, and 44c to oscillate when moving within the corresponding guide slots 54a, 54b, and 54c.

[0048] In the embodiments described above, the shells 50a and 50b define three guide slots 54a, 54b, and 54c, respectively, which accommodate the corresponding pins 44a, 44b, and 44c. However, depending on the type and amplitude of movement that the knee brace 20 is designed to allow or restrict, other implementations may have more or fewer guide slots and corresponding pins than three. The guide slots and pins may also be designed as any mixed configuration in which the guide slots and pins are integrated into either the femoral shell or the tibial shell, or both. Furthermore, the guide slots and pins can be integrated into any positional configuration or permutation. That is, any guide slot can be integrated into either the tibial shell or the femoral shell, and the corresponding pin can be integrated into the opposite shell.

[0049] For example, referring to Figures 6A through 6C, three different hinge configurations are shown, each having two guide slots and two corresponding pins. In the embodiment of Figure 6A, hinge 130 includes two guide slots 154 located in the tibial portion 134 and two pins 144 located in the femoral portion 132. In the embodiment of Figure 6B, hinge 230 includes two guide slots 254, one located in the tibial portion 234 and the other in the femoral portion 232. It also includes two pins 244, one located in the tibial portion 234 and the other in the femoral portion 232. In the embodiment of Figure 6C, hinge 330 includes two guide slots 354 located in the femoral portion 332 and two pins 344 located in the tibial portion 334. Each of these hinge configurations can also be reversed (for example, elements located in the tibial portion can be placed in the femoral portion, and vice versa). Furthermore, these embodiments are merely illustrative examples of three possible hinge configurations, and it should be understood that other alternative configurations and permutations are possible without departing from the scope of this disclosure.

[0050] Referring now to Figures 6D through 6G, four other hinge configurations are shown, each having a different configuration and permutation of three guide slots and three pins. In the embodiment of Figure 6D, the hinge 430 includes three guide slots 454, all located in the tibial portion 434, and three pins 444, all located in the femoral portion 432. In the embodiment of Figure 6E, the hinge 530 includes three guide slots 554, i.e., two guide slots 554 located in the tibial portion 534 and one guide slot 554 located in the femoral portion 532, and three pins 544, i.e., one pin 544 located in the tibial portion 534 and two pins 544 located in the femoral portion 532. In the embodiment shown in Figure 6F, the hinge 630 includes three guide slots 654, i.e., two guide slots 654 located in the femoral portion 632 and one guide slot 654 located in the tibial portion 634, and three pins 644, i.e., one pin 644 located in the femoral portion 632 and two pins 644 located in the tibial portion 634. In the embodiment shown in Figure 6G, the hinge 730 includes three guide slots 754, all located in the femoral portion 732, and three pins 744, all located in the tibial portion 734. Each of these hinge configurations can also be reversed (for example, elements located in the tibial portion can be placed in the femoral portion, and vice versa). Furthermore, these embodiments are merely illustrative of four possible hinge configurations, and it should be understood that other alternative configurations and permutations are possible without departing the scope of this disclosure.

[0051] Design considerations may include ensuring appropriate compromises between various parameters, such as stability, motion control, range of motion, hinge size, and the number of required parts. In the illustrated embodiment, three slots and three corresponding pins are shown. The corresponding slots and pins, regardless of the number of slots and pins, serve to guide the pivotal movement of the femoral and tibial portions relative to each other. Thus, either the femoral or tibial portion of the hinge has at least one guide slot defined within the corresponding shell, and the other of the femoral or tibial portion has at least one pin extending within that at least one guide slot. In most embodiments, two or three guide slots and their corresponding pins are likely to be used, but it is also possible to use a single slot / pin or more than three slots / pins.

[0052] Referring to Figures 7A to 7C, the cooperation between the pins 44a, 44b, and 44c (omitted here for clarity and instead shown are holes 42a, 42b, and 42c) and the corresponding guide slots 54a, 54b, and 54c during flexion of the knee orthosis 20 is shown. The pins 44a, 44b, and 44c are fixed to the femoral shells 40a and 40b, and the guide slots 54a, 54b, and 54c allow the shells 50a and 50b to move relative to the shells 40a and 40b while being guided by the guide slots 54a, 54b, and 54c.

[0053] Referring to Figures 8A to 8F, it is shown that the pin axes 46a, 46b, and 46c extend through the hinge 30a toward the center of rotation 10 of the knee. More specifically, in Figures 8A and 8B, the hinge 30a is at a flexion angle of 10°, and the axes 46a, 46b, and 46c converge and intersect at the center of rotation 10 of the knee at this instantaneous flexion angle. In Figures 8C and 8D, the hinge 30a is at a flexion angle of 60°, and the axes 46a, 46b, and 46c converge and intersect at the center of rotation 10 of the knee at this instantaneous flexion angle. Similarly, in Figures 8E and 8F, the hinge 30a is at a flexion angle of 120°, and the axes 46a, 46b, and 46c converge and intersect at the center of rotation 10 of the knee at this instantaneous flexion angle. As seen in Figures 8A, 8C, and 8E, the instantaneous center of rotation 10 moves along a trajectory 10a contained in the sagittal plane 12 (see Figure 9A) when the hinge 30a is flexed, and the axes 46a, 46b, and 46c all converge and intersect at the instantaneous center of rotation 10 regardless of the flexion angle of the hinge 30a (i.e., at all flexion angles of the hinge 30a, the axes 46a, 46b, and 46c intersect at the corresponding instantaneous center of rotation 10). In other words, the shapes of the shells 40a, 40b, 50a, and 50b, and the configuration of the pins 44a, 44b, and 44c and guide slots 54a, 54b, and 54c allow the hinge 30a to follow the center of rotation 10 of the knee throughout the entire flexion range of the knee orthosis 20. This feature can help the knee orthosis allow for femoral rollback and screw-home motion during knee flexion and extension.

[0054] Referring to Figures 9A to 9D, the method for forming the ellipsoid 60 for designing the shells 40a, 40b, 50a, and 50b is shown. In Figure 9A, the initial positions of the sagittal plane 12, frontal plane 14, and transverse plane 16 are shown, corresponding to a flexion angle of 0° of the knee and knee brace 20. An initial origin 70 exists at the intersection of planes 12, 14, and 16, corresponding to COR 10 at a flexion angle of 0°.

[0055] In Figure 9B, the coordinate system defined by the sagittal, frontal, and transverse planes, i.e., planes 12, 14, and 16, is translated and transformed (i.e., pivoted) to coincide with a selected position along the knee flexion trajectory. As a result, the translated and pivoted planes are shown as planes 12', 14', and 16', with the frontal plane 14' positioned at a predetermined flexion angle relative to the initial position of the frontal plane 14 with respect to the sagittal plane 12. In the illustrated implementation, this predetermined flexion angle is approximately 60°. The predetermined translation and rotation angles are selected to correspond to an intermediate flexion configuration of the knee in this implementation, and the abduction and rotation angles are coupled to this intermediate flexion configuration. In this implementation, approximately 6° of external rotation and approximately 4° of abduction are coupled.

[0056] Planes 12′, 14′, and 16′ are also translated along the anterior-posterior axis 12a (see Figure 9C) and the sagittal plane 12, specifically along the supin-supin axis 12b. The translation of the initial origin 70 corresponds to the translation of COR 10 in the intermediate flexion configuration of the knee. At the intersection of the moved planes 12′, 14′, and 16′, i.e., the translated and rotated planes as described above, there exists a translated origin 72, which corresponds to the position of COR 10 at a flexion angle of 60°. The anterior-posterior and supin-supin directional shifts 74 correspond to the distance between the translated origin 72 and the initial origin 70. The shifts 74 correspond to the displacement of COR 10 of the knee along the trajectory 10a between the initial origin 70 and the translated origin 72. In this implementation, planes 12′, 14′, and 16′ are translated approximately 4 mm posteriorly and approximately 3 mm downward. In this specific selected flexion configuration, namely the intermediate flexion configuration, the tibial ellipsoid perfectly coincides with the femoral ellipsoid, thereby minimizing or virtually eliminating shell deformation.

[0057] Other predetermined angles are also possible. For example, in certain embodiments, the predetermined angle is in the range of 40° to 80° (including the 40° and 80° ends). Alternatively, the predetermined angle may be in the range of 30° to 90°, or in the range of 20° to 100°. However, by preferably selecting a predetermined angle of about 60°, interference between the ellipsoidal shells 40a, 40b, 50a, and 50b at a bending angle of 60° is reduced compared to the starting bending configuration (i.e., bending angle 0°) and the ending bending configuration (i.e., bending angle 120°). The ending bending configuration may differ in other implementations and may be located at a position greater than a bending angle of 120°. In addition, in certain implementations, the starting bending configuration may be selected not to start from a bending angle of 0°, for example, to prevent overextension.

[0058] In Figure 9C, the major axis 80 corresponds to the inclined anterior-posterior axis 12a', which is defined by the inclined surfaces 12', 14', and 16'. Therefore, the ellipsoid 60 has a length 80a along the major axis 80 and a width 84a along the minor axis 84. The minor axis 84 is perpendicular to the major axis 80. The width 84a of the minor axis 84 is based on the morphological characteristics of the wearer's knee, such as the width of the wearer's knee. In one implementation configuration, the width 84a corresponds to the distance 82 between the hinges 30a and 30b. The length 80a of the major axis 80 corresponds to the width 84a of the minor axis plus the anterior-posterior shift 74 of the COR 10 along the trajectory 10a. Therefore, in one implementation configuration, the length 80a corresponds to the distance 82 between the hinges 30a and 30b (see Figure 2) plus the anterior-posterior shift 74. The distance 82 is based on the morphological characteristics of the wearer's knee, such as the width of the wearer's knee. In other words, the short axis 84 corresponds to the width of the knee, and the long axis 80 corresponds to the short axis 84 plus an anterior-posterior shift of 74. Therefore, the long axis 80 is longer than the short axis 84 by an amount corresponding to the anterior-posterior shift of 74.

[0059] Referring to Figure 9D, the ellipsoid 60 is obtained by rotation around the major axis 80, having a length 80a along the major axis 80 and a length 84a along the minor axis 84, respectively. The resulting ellipsoid 60 is based on the morphological characteristics of the wearer's knee, such as the width of the wearer's knee.

[0060] Referring to Figures 10A and 10B, the ellipsoid 60 is superimposed on a model of the wearer's tibial plateau 62 in Figure 10A, with the center of the ellipsoid 60 located at the instantaneous COR 10 of the knee at a flexion angle of 60°. In Figure 10B, portions 60a and 60b of the ellipsoid 60 are separated to define the shapes of the ellipsoid shells 40a, 40b, 50a, and 50b. In Figure 10C, the instantaneous flexion axis 18 in the range of motion of the hinges 30a and 30b (e.g., from 0° to 120°) is projected onto the ellipsoid shell portions 60a and 60b to define the guide slot 54a. Once the ellipsoidal shapes 60 of the shells 40a, 40b, 50a, and 50b are defined, the shells 40a, 40b, 50a, and 50b can be dimensionally set and / or adjusted to conform to the wearer's morphological features.

[0061] Hinges 30a and 30b, equipped with ellipsoidal shells 40a, 40b, 50a, and 50b (i.e., shells having shapes corresponding to parts of ellipsoids such as ellipsoid 60), have several advantages over hinges equipped with shells corresponding to spherical arcs, i.e., shells with a constant radius of curvature on the shell surface. Hinges equipped with shells corresponding to spherical arcs allow pure rotation, but do not necessarily allow simultaneous rotation and translational motion, such as that which occurs during knee flexion. For example, an embedded spherical shell allows rotation in three relative positions, but does not allow translational motion between them. In contrast, hinges equipped with shells corresponding to parts of an ellipsoid can better accommodate the combination of rotation and translational motion that occurs during knee flexion.

[0062] As best illustrated in Figure 1A, COR10 translates along the sagittal plane 12 during knee flexion. In addition, the ellipsoidal shells 40a, 40b, 50a, and 50b are also designed to minimize interference when the hinges 30a and 30b engage with each other in an intermediate flexion point configuration, for example, at a flexion angle of 60°. The term “interference” as used in this context herein is further defined below. These features reduce friction and / or deformation between the engaging surfaces 41 and 52 in the intermediate flexion point configuration of the hinges 30a and 30b compared to the start flexion configuration (i.e., flexion angle 0°) and / or the end flexion configuration (i.e., flexion angle 120°). Thus, at the intermediate flexion point, the amount of interference (friction and / or deformation) is minimized, and the deformation increases with the change in flexion angle. This interlocking design with minimal interference at the center limits absolute deformation at both the start and end points of rotation. The reduction in friction reduces wear on the engagement surfaces 41 and 52, improving the durability of the shells 40a, 40b, 50a, and 50b, and also improving motion control. In addition, parts of the ellipsoidal shells 40a, 40b, 50a, and 50b, especially their outer portions, may be removed or reduced (e.g., by trimming, grinding, or other methods of material removal) to further reduce unwanted deformation of the shells 40a, 40b, 50a, and 50b.

[0063] In other embodiments, the shells 40a, 40b, 50a, and 50b have ellipsoidal shapes obtained using other construction methods. In the implementation shown in Figures 11A to 11C, the shells 40a, 40b, 50a, and 50b correspond to a portion of the ellipsoid 60a (i.e., an aspherical shape with an inconsistent radius of curvature of the surface). The surface 60a is formed by a circle defined within the cross section 16, whose center corresponds to COR 10. The diameter of the circle is the width of the knee. At 5° increments, a new circle is defined instantaneously centered at COR 10 and having the same diameter corresponding to the width of the knee. In Figure 11B, the ellipsoid 60a is generated by rotation around the anterior-posterior axis 12a, and by retaining the resulting outer surface, one continuous closed outer surface of the ellipsoid 60a is defined. In Figure 11C, the shells 50a and 50b are obtained by separating a portion of the ellipsoid 60a.

[0064] Referring to Figures 12A to 12C, a first semicircle 64a centered at instantaneous COR10 at a bending angle of 0° is defined within the cross-section 16. A second semicircle 64b centered at instantaneous COR10 at a bending angle of 120° is defined within the cross-section 16. A front-to-back shift 74 exists between the two COR10s, defining the major axis 84 of the ellipsoid 60b. The two semicircles are connected by a line 64c that satisfies the tangent condition for both semicircles. The ellipsoid 60b (Figure 12C) is obtained by rotation around the major axis 84.

[0065] As used herein, the term “interference” means contact between surfaces. This contact may, in some cases, cause friction and / or deformation of one or more surfaces or parts of the elements in contact with each other. In this context, interference does not mean that parts or surfaces occupy the same volume in three-dimensional space, but rather that friction and / or deformation occur.

[0066] While various connections between elements are described in the preceding description and drawings, these connections are general in nature and may be direct or indirect unless otherwise specified, and this specification is not intended to limit them in this respect. A connection between two or more elements may refer to a direct or indirect connection. An indirect connection may include one or more intervening elements. Therefore, the terms “connected” or “joined” may include both direct connections (two elements joined together are in contact with each other) and indirect connections (at least one additional element is located between the two elements).

[0067] As used herein, “comprises,” “comprising,” or any other variation thereof shall be interpreted as meaning non-exclusive inclusion. That is, a process, method, article, or apparatus that includes an enumeration of elements does not include only the enumerated elements, but may include other elements not expressly enumerated, or other elements that are inherently present in the process, method, article, or apparatus.

[0068] While various aspects of this disclosure have been disclosed, it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of this disclosure. For example, several aspects and embodiments described herein include certain features. Even if these specific features are described individually, some or all of these features may be combined with any of the aspects, and this combination is also within the scope of this disclosure. The phrases “various embodiments,” “one embodiment,” “embodiment,” and “exemplary embodiment” mean that the described embodiments may include certain configurations, structures, or characteristics, but not all embodiments necessarily include those configurations, structures, or characteristics. Furthermore, these expressions do not necessarily refer to the same embodiment. The indefinite article “a” used herein is intended to include “one or more” with respect to a particular element, and similarly, the definite article “the” does not exclude the possibility that there may be multiple elements. In addition, the expression “at least one of” used herein is understood to mean “and / or.” In other words, the expression “at least one of X and Y” is understood to mean X only, Y only, or both X and Y.

[0069] The embodiments described herein provide non-limiting examples of possible implementations of the Art. Those skilled in the art considering this disclosure will recognize that modifications can be made to the embodiments described herein without departing from the scope of the Art. Furthermore, further modifications can be made by those skilled in the art based on this disclosure, and these modifications also fall within the scope of the Art.

Claims

1. A thigh cuff configured to engage with the wearer's upper thigh, A tibial cuff configured to engage with the lower leg of the wearer, A hinge that pivotably connects the thigh cuff to the tibial cuff. Equipped with, The hinge has a femoral portion connected to the femoral cuff and a tibial portion connected to the tibial cuff, and the femoral portion and the tibial portion are engaged with each other and include a shell configured to pivot relative to each other about a center of rotation, the first shell of which includes an engaging surface facing a complementary engaging surface on the second shell of which, and the engaging surface and the complementary engaging surface are The long axis extending within the sagittal plane, A minor axis perpendicular to the aforementioned major axis, The length of the ellipsoid along the major axis is greater than the length along the minor axis, Rotation around the aforementioned major axis and A knee brace having a shape corresponding to a part of the ellipsoid defined by [the specified method].

2. The knee brace according to claim 1, wherein the long axis corresponds to the anterior-posterior axis, and the long axis is positioned in the sagittal plane at a predetermined angle with respect to the frontal plane perpendicular to the sagittal plane.

3. The knee brace according to claim 2, wherein the predetermined angle is between 40 and 80 degrees.

4. The knee orthosis according to any one of claims 1 to 3, wherein the length of the ellipsoid along the minor axis is determined based on the morphological characteristics of the wearer's knee.

5. The knee brace according to claim 4, wherein the morphological feature is the width of the wearer's knee.

6. The knee orthosis according to any one of claims 1 to 5, wherein the length of the ellipsoid along the major axis is greater than the length of the ellipsoid along the minor axis by an amount corresponding to the anterior-posterior shift of the rotation center of the knee.

7. In the intermediate bending point configuration of the hinge, there is a first interference between the shells, In the starting point bending configuration, there is a second interference between the shells, In the terminal bending configuration, there is a third interference between the shells, The knee brace according to any one of claims 1 to 6, wherein the first interference is less than at least the second interference or the third interference.

8. The knee orthosis according to any one of claims 1 to 7, wherein either the femoral portion or the tibial portion of the hinge has at least one guide slot defined within the corresponding shell, and the other of the femoral portion or the tibial portion has at least one pin extending within the at least one guide slot for guiding the pivot of the femoral portion and the tibial portion relative to each other, the at least one pin defining an axis intersecting the center of rotation of the wearer's knee.

9. The knee orthosis according to claim 8, wherein the hinge includes two or three guide slots and two or three pins, the two or three guide slots being located in the femoral portion, the tibial portion, or a combination thereof, and the two or three pins being located in the femoral portion, the tibial portion, or a combination thereof.

10. The knee orthosis according to claim 8 or 9, wherein the thigh portion of the hinge has at least one guide slot and at least one pin, and the tibial portion of the hinge has at least one guide slot and at least one pin.

11. The knee brace according to any one of claims 1 to 10, wherein the rotation center is the instantaneous rotation center in a given bending configuration of the hinge, and the instantaneous rotation center moves along a trajectory when the hinge is bent.

12. The knee brace according to any one of claims 8 to 10, wherein the rotation center is an instantaneous rotation center in a given bending configuration of the hinge, the instantaneous rotation center moves along a trajectory when the hinge is bent, and the axis of the at least one pin intersects the instantaneous rotation center regardless of the bending configuration of the hinge.

13. The knee orthosis according to claim 11 or claim 12, wherein the trajectory is contained within the sagittal plane.

14. A thigh cuff configured to engage with the wearer's upper thigh, A tibial cuff configured to engage with the lower leg of the wearer, A hinge that pivotably connects the thigh cuff to the tibial cuff. Equipped with, A knee brace comprising a hinge having a femoral portion connected to the femoral cuff and a tibial portion connected to the tibial cuff, wherein the femoral portion and the tibial portion are engaged with each other and include corresponding shells configured to pivot relative to each other about a center of rotation, the femoral portion or the tibial portion having at least one guide slot defined within the corresponding shell, the other femoral portion or the tibial portion having at least one pin extending from the other shell and housed within the at least one guide slot that guides the pivot of the femoral portion and the tibial portion relative to each other, the at least one pin defining a pin axis intersecting the center of rotation of the wearer's knee.

15. The knee brace according to claim 14, wherein the rotation center is the instantaneous rotation center in a given bending configuration of the hinge, the instantaneous rotation center moves along a trajectory when the hinge is bent, and the pin axis intersects the instantaneous rotation center regardless of the bending configuration of the hinge.

16. The knee orthosis according to claim 15, wherein the aforementioned trajectory is contained within the sagittal plane.

17. The aforementioned shell is The long axis extending in the sagittal plane, A minor axis perpendicular to the aforementioned major axis, The length of the ellipsoid along the major axis is longer than the length along the minor axis, Rotation around the aforementioned major axis and A knee brace according to any one of claims 14 to 16, having a shape corresponding to a part of the ellipsoid defined by the ellipsoid.

18. The knee brace according to claim 17, wherein the long axis corresponds to the anterior-posterior axis, and the long axis is positioned in the sagittal plane at a predetermined angle with respect to the frontal plane perpendicular to the sagittal plane.

19. The knee brace according to claim 18, wherein the predetermined angle is between 40 and 80 degrees.

20. The knee orthosis according to any one of claims 17 to 19, wherein the length of the ellipsoid along the minor axis corresponds to the morphological characteristics of the wearer's knee.

21. The knee brace according to claim 20, wherein the morphological feature is the width of the wearer's knee.

22. The knee orthosis according to claim 20 or claim 21, wherein the length of the ellipsoid along the major axis is longer than the length of the ellipsoid along the minor axis by an amount corresponding to the anterior-posterior shift of the rotation center of the knee.

23. In the intermediate bending point configuration of the hinge, there is a first interference between the shells, In the starting point bending configuration, there is a second interference between the shells, In the terminal bending configuration, there is a third interference between the shells, The knee brace according to any one of claims 17 to 22, wherein the first interference is smaller than at least the second interference or the third interference.

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