JP7708038B2 - Knee brace - Google Patents

Description

This disclosure relates to knee braces.

One type of knee joint movement is flexion and extension. In knee flexion, a rolling movement occurs first, in which the lower end of the femur rolls over the upper end of the tibia, and then when the knee joint is bent, a sliding movement occurs in which the femur moves backwards, creating a compound movement known as a roll-back movement. Therefore, the trajectory of the central axis of the knee joint is not constant, but has the property of moving.

Knee braces are worn on the lower limbs of users who are undergoing walking training for daily walking movements or rehabilitation. Patent Document 1 discloses a knee joint assist device in which the rotation axis of a moving gear is attached so as to roughly coincide with the rotation axis of the knee joint of the wearer in an upright position in order to reproduce a movement similar to a rollback movement, and when the user bends and straightens the knee, the moving gear can move along a guide groove while rotating around the rotation axis.

JP 2021-029596 A

The inventor has found the following problem. There are individual differences in the rollback movement of the knee joint. A misalignment occurs between the rotation axis of the knee brace and the rollback movement of the user's knee joint, which causes a problem in that the position of the knee brace shifts when wearing it or when walking after wearing it.

This disclosure was made in consideration of the above problems, and aims to provide a knee brace that can suppress misalignment of the wearing position of the knee brace according to individual differences in rollback movement.

The knee brace according to the present disclosure comprises:
A knee brace attached to a user's lower leg,
a first link fixed to one of a lower leg side and an upper leg side of the lower leg via a first supporter;
A fixing frame fixed to the other side of the lower leg side and the upper leg side via a second supporter;
a second link fixable to the stationary frame;
a guide member provided on the fixed frame for guiding a displacement of the second link;
a joint that rotatably connects the first link and the second link,
The second link is slidable along the guide member, following the movement of the knee joint of the user.

In the knee brace disclosed herein, the second link can slide along the guide member, following the movement of the user's knee joint. Therefore, it is possible to provide a knee brace that can suppress misalignment of the wearing position of the knee brace according to the individual differences in the rollback movement of the user's knee joint, rather than within a range of rollback movement that is assumed in advance.

The guide member may be formed in a rail shape and be slidable while engaged with the second link. When misalignment can occur in only one direction, this configuration can provide a knee brace that can prevent misalignment of the mounting position of the knee brace.

When attached to the user's lower leg, the second link can slide along the guide member, following the movement of the user's knee joint, and when the user walks, the second link may be fixed to the fixed frame. With this configuration, it is possible to prevent the device from shifting position when attached to the user's lower leg.

The first link may be arranged on the lower leg side, and the second link may be arranged on the upper leg side. With this configuration, when the user is in a standing position, the person wearing the knee brace on the user can adjust the position of the second link at a higher position than if the second link was arranged on the lower leg side. This makes it easier to fix the second link than if the second link was arranged on the lower leg side, and shortens the time it takes to put on the knee brace.

This disclosure provides a knee brace that can prevent the brace from shifting from its mounting position depending on individual differences in rollback motion.

1 is a side view showing a state in which the knee brace according to embodiment 1 is attached to a user's lower leg. FIG. 1 is a rear view showing a state in which the knee brace according to the first embodiment is attached to a user's lower leg. FIG. 1A to 1C are side views showing a series of steps for attaching the knee brace in accordance with embodiment 1 to a user's lower leg. 1A to 1C are side views showing a series of steps for attaching the knee brace in accordance with embodiment 1 to a user's lower leg. 1A to 1C are side views showing a series of steps for attaching the knee brace in accordance with embodiment 1 to a user's lower leg. FIG. 11 is a rear view showing the knee brace according to the second embodiment. FIG. 11 is a rear view showing the knee brace according to the third embodiment.

Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the drawings.
The right-handed xyz coordinate system shown in the figure is for the convenience of explaining the positional relationship of the components. Unless otherwise specified, the positive direction of the z axis is the vertical upward direction. Furthermore, the xy plane is the horizontal plane.

<First embodiment>
The knee brace according to the present embodiment is a knee brace that is attached to the lower limbs of a user, and is attached to a trainee who is undergoing walking training for rehabilitation or the like. The trainee, who is the user, performs walking training while wearing the walking assistance device. For example, a trainee who is a hemiplegic patient suffering from paralysis in one lower limb may wear the walking assistance device on the affected leg, which is the paralyzed leg. The knee brace may be used not only during walking training, but also during everyday walking, walking in a hospital, walking outdoors, etc.

First, the configuration of the knee brace 10 according to the first embodiment will be described with reference to Figs. 1 and 2. Fig. 1 is a side view showing the knee brace 10 according to the first embodiment attached to the lower limb L of a user. Fig. 2 is a rear view showing the knee brace 10 according to the first embodiment attached to the lower limb L of a user. The lower limb L in each drawing refers to the foot (not shown), the lower leg L1, and the upper leg L2, in that order from the negative side of the z axis. The lower leg L1 indicates the part from the ankle joint to the knee joint N. The upper leg L2 indicates the part from the knee joint N to the hip joint. Note that in this embodiment, an example in which the knee brace 10 is attached to the right lower limb L will be described as an example, but a knee brace with a symmetrical configuration may be attached to the left lower limb, or may be attached to both lower limbs.

As shown in Figures 1 and 2, the knee brace 10 includes a first supporter 11, a second supporter 21, a first link 12, a second link 22, a fixed frame 23, a guide member 23a, a fixed portion 13, a fixed portion 24, and a joint 31.

As shown in FIG. 1, the first supporter 11 and the second supporter 21 fix each component of the knee brace 10 to the side of the user's lower leg L. The first supporter 11 and the second supporter 21 have a belt-like structure formed from a stretchable elastic body, a resin material, a fiber material, or the like. Below, as an example, a case where the first link 12 is fixed to the lower leg L1 side via the first supporter 11 and a case where the fixing frame 23 is fixed to the upper leg L2 side via the second supporter 21 will be described.

Refer to FIG. 2 for a moment. As shown in FIG. 2, the first supporter 11 may further include a hook-and-loop fastener 11a on the front side (x-axis positive side) of the lower leg L1 for use in attaching the first supporter 11 to the user's lower leg L1, and the second supporter 21 may further include a hook-and-loop fastener 21a on the front side (x-axis positive side) of the upper leg L2 for use in attaching the first supporter 11 to the user's upper leg L2. The first supporter 11 is brought into contact with the user's lower leg L1 from the rear side (x-axis negative side) and wrapped around the lower leg L1, and is removably fixed to the front side (x-axis positive side) of the lower leg L1. Similarly, the second supporter 21 is brought into contact with the user's upper leg L2 from the rear side (x-axis negative side) and wrapped around the upper leg L2, and is removably fixed to the front side (x-axis positive side) of the upper leg L2. By using the hook-and-loop fasteners 11a and 21a, the user can easily attach and remove the knee brace 10.

Return to FIG. 1. As shown in FIG. 1, the first link 12 is a rectangular plate-like member extending along the tibia on the xz plane. The first link 12 is fixed to the side of the first supporter 11 by a fixing portion 13. The first link 12 may be fixed to the first supporter 11 by the fixing portion 13 using, for example, a bolt. The second link 22 is a rectangular plate-like member extending along the femur on the xz plane.

As shown in FIG. 1, the fixing frame 23 is a rectangular plate-like member extending along the femur on the xz plane. The fixing frame 23 is fixed to the side of the second supporter 21 by a fixing part (not shown). The fixing frame 23 may be fixed to the second supporter using, for example, a bolt or the like.

As shown in FIG. 1, the fixed frame 23 is provided with a guide member 23a. When the second link 22 is not fixed to the fixed frame 23, the second link 22 can slide along the guide member 23a, following the movement of the knee joint N of the user. The guide member 23a is arranged on the xz plane on the y-axis positive side of the fixed frame 23. The guide member 23a may have a U-shape as shown in FIG. 1. When the fixed frame 23 is fixed to the upper leg L2 side via the second supporter 21, the guide member 23a is arranged so that the opening side of the U-shape faces the z-axis negative side. When the width of the second link 22 is W1 and the width of the inside of the U-shape of the guide member 23a is W2, it is preferable to arrange them so that W1≦W2. By setting the width in this way, the second link 22 can slide along the guide member 23a, following the movement of the knee joint N of the user. The displacement of the second link 22 that occurs when the knee brace 10 is attached to the user's lower leg L will be described in detail below with reference to Figures 3 to 5.

The second link 22 can be fixed to the fixed frame 23 by the fixing portion 24 as needed by the user. Note that FIG. 1 shows the second link 22 in a state in which it can slide along the guide member 23a, following the movement of the user's knee joint N, i.e., in a state in which it is not fixed to the fixed frame 23. The second link 22 may be fixed to the fixing portion 24 using, for example, bolts, pins, hook-and-loop fasteners, clamps, etc. When using pins, holes may be provided at predetermined intervals in the fixed frame 23, and the pins may be inserted into the holes.

As shown in FIG. 1, the joint 31 connects the upper end (the end on the positive side of the z-axis) of the first link 12 and the lower end (the end on the negative side of the z-axis) of the second link 22 so that they can rotate around a rotation axis Ax (see FIG. 2). The first link 12 and the second link 22 form a link mechanism that can rotate around the rotation axis Ax of the joint 31. The joint 31 is positioned at the height of the knee joint N so that the position of the rotation axis Ax of the joint 31 coincides with the position of the knee joint N. The joint 31 may further include a damper such as a rotary damper.

The arrangement of each component may be upside down. That is, the first supporter 11 may be arranged on the upper leg L2 side, and the second supporter 21 may be arranged on the lower leg L1 side. When the supporters are arranged in this way, the fixing frame 23 may be fixed to the lower leg L1 side via the second supporter 21, and the first link 12 may be fixed to the upper leg L2 side via the first supporter 11. Also, the first supporter 11 may be arranged on the lower leg L1 side, and the second supporter 21 on the upper leg L2 side, with the arrangement of the first link 12 and the fixing frame 23 being upside down.

The hook-and-loop fasteners 11a, 21a on the first supporter 11 and the second supporter 21 may be removable structures other than hook-and-loop fasteners. For example, fastening means such as buttons, pins, bands, bolts, clamps, etc. may be used. In addition, a short leg brace may be further attached to the underside of the knee brace 10.

In addition, as long as the second link 22 can slide along the guide member 23a, the guide member 23a may have a shape that does not have a U-shaped bottom. For example, the guide member 23a may have a rod-like shape extending in the z-axis direction at each end on the positive and negative sides of the x-axis of the fixed frame 23, and may be arranged so as to face each other.

The following describes the sequence of steps for attaching the knee brace 10 to the user's lower leg L with reference to Figures 3 to 5. Figures 3 to 5 are side views showing the sequence of steps for attaching the knee brace 10 according to embodiment 1 to the user's lower leg L.

Figure 3 shows a state in which the knee joint N of the right lower leg L of a user in a seated position is extended, with a first link 12 attached to the lower leg L on the right side on the lower leg L1 side via a first supporter 11, and a fixed frame 23 attached to the lower leg L on the right side on the upper leg L2 side, which is the same side as the lower leg L1, via a second supporter 21. The second link 22 is not fixed to the fixed frame 23, and is in a state in which it can slide along the guide member 23a, following the movement of the user's knee joint N.

Figure 4 shows a state in which the user is in the middle of moving from the sitting position with the knee joint N extended in Figure 3 to a standing position with the knee joint N bent. As described above, the second link 22 is not fixed to the fixed frame 23. Therefore, as the knee joint N bends, the second link 22 is pulled by the first link 12 fixed to the first supporter 11 via the joint 31 and displaced. The second link 22 can slide along the inner surface of the guide member 23a, as shown by the dashed line in Figure 4, following the rollback movement of the user's knee joint N.

The bending of the knee joint that occurs when transitioning from a seated position to a standing position is greater than the bending of the knee joint that occurs when walking using a knee brace. In this embodiment of the knee brace, the second link is not fixed, so that the position of the knee brace can be prevented from shifting when transitioning from a seated position to a standing position.

Figure 5 shows the second link 22 fixed to the fixing part 24 of the fixed frame 23 when the knee joint N of the user has transitioned to a standing position and is extended. The second link 22, which was displaced when the knee joint N was bent in Figure 4, has returned to the position in Figure 3 when the first supporter 11 was attached to the side of the lower leg L1 and the second supporter 21 was attached to the side of the upper leg L2, due to the transition to a standing position. Therefore, while maintaining the attachment positions of the first supporter 11 and second supporter 21 attached in the sitting position of Figure 3, the second link 22 can also be fixed in an appropriate position according to the needs of the user.

The inventor found the following problem. There are individual differences in the rollback movement of the knee joint. A misalignment occurs between the rotation axis of the knee brace and the rollback movement of the user's knee joint, which causes a misalignment of the wearing position of the knee brace when wearing it or when walking after wearing it.

In contrast, the knee brace according to this embodiment includes a first link fixed to one side of the lower leg, either the lower leg or the upper leg, via a first supporter, a fixed frame fixed to the other side of the lower leg or the upper leg, via a second supporter, a second link that can be fixed to the fixed frame, a guide member provided on the fixed frame that guides the displacement of the second link, and a joint that rotatably connects the first link and the second link.

In the knee brace according to this embodiment, the second link can slide along the guide member, following the movement of the user's knee joint. Therefore, it is possible to provide a knee brace that can suppress misalignment of the mounting position of the knee brace according to the individual differences in the rollback movement of the user's knee joint, rather than within a range of rollback movement that is assumed in advance.

In addition, in the past, in order to prevent the position of the knee brace from shifting, the supporter was temporarily fixed in the sitting position, and then the knee brace was attached by performing a permanent fixation including a task of rewrapping the supporter after transitioning to a standing position. However, re-attaching the supporter in a standing position entailed the risk of falling for users with weak trunks. In contrast, in the knee brace according to the present embodiment, while each supporter is fixed in the sitting position, the second link is not fixed when transitioning from the sitting position to the standing position. Therefore, when transitioning from the sitting position to the standing position, the position of the first supporter and the second supporter is prevented from shifting, so there is no need to re-wrap each supporter in a standing position. Therefore, the knee brace according to the present embodiment reduces the risk of the user falling when wearing it, and can be worn more safely.

<Embodiment 2>
The knee brace according to this embodiment differs from embodiment 1 in that the guide member of the fixed frame is formed in a rail shape and the second link is engaged with it. The other configurations are the same as those of embodiment 1. Therefore, the same components as those of embodiment 1 are given the same reference numerals and their explanations are omitted.

Figure 6 is a rear view showing the knee brace 20 according to the second embodiment. As shown in Figure 6, the fixed frame 43 of the knee brace 20 according to this embodiment has a guide member 43a in the xy plane on the negative side of the y axis. The fixed frame 43 is a rectangular plate-like member extending on the xz plane, and is fixed to the second supporter 21 by a fixing member such as a bolt (not shown). The guide member 43a is formed in a rail shape, and is engaged with the second link 42 having a structure that engages with the rail-shaped shape.

The second link 42 engages with a rail-shaped guide member 43a and can slide along the guide member 43a. As shown by the dashed line and double-pointing black arrows in the right diagram of Figure 6, the second link 42 slides in response to bending and straightening of the user's knee joint.

When the user has transitioned to a standing position and the knee joint is extended, the second link 42 is fixed to the fixed frame 43. With the knee brace 20 according to this embodiment, it is only necessary to position the second link in the vertical direction, so that the second link can be easily fixed when the user is in a standing position, and the wearing time can be reduced. As with the first embodiment, the arrangement of each component may be upside down.

<Third embodiment>
7 is a rear view showing a knee brace according to embodiment 3. The knee brace according to this embodiment differs from embodiment 1 in that it includes a first link 12, a second link 22, a fixed frame 23, a guide member 23a, a fixed portion 13, a fixed portion 24, and a joint 31 on both sides of the lower leg L, and each configuration is the same as in embodiment 1. Therefore, the same components as in embodiment 1 are given the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 7, by providing the first link 12, the second link 22, the fixed frame 23, the guide member 23a, the fixed part 13, the fixed part 24, and the joint 31 on both sides of the lower leg L, the user can walk more stably.

Note that this disclosure is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present disclosure.

10, 20 Knee brace, 11 First supporter, 11a Hook and loop fastener, 12 First link, 13 Fixing part, 21 Second supporter, 21a Hook and loop fastener, 22 Second link, 23 Fixing frame, 23a Guide member, 24 Fixing part, 31 Joint, 42 Second link, 43 Fixing frame, 43a Guide member, L Lower leg, L1 Lower leg, L2 Upper leg, N Knee joint

Claims (3)

A knee brace attached to a user's lower leg,
a first link fixed to one of a lower leg side and an upper leg side of the lower leg via a first supporter;
A fixing frame fixed to the other side of the lower leg side and the upper leg side via a second supporter;
a second link fixable to the stationary frame;
a guide member provided on the fixed frame for guiding a displacement of the second link;
a joint that connects the first link and the second link rotatably around the same rotation axis ,
The second link is slidable along the guide member, following the movement of the knee joint of the user.
Knee brace. The knee brace according to claim 1, wherein the guide member is formed in a rail shape and is slidable while engaged with the second link. The knee brace according to claim 1 or 2, wherein the first link is disposed on the lower leg side, and the second link is disposed on the upper leg side.