JP7457471B2 - short leg orthosis - Google Patents

Description

The present invention relates to a short leg brace that assists walking.

Movement disorders such as spasticity and hemiplegia can occur as one of the after-effects of illnesses such as stroke. Movement disorders can make walking difficult, and short leg orthoses are known as devices to assist ankle plantar flexion in such cases.

For example, Patent Document 1 discloses a short leg orthosis configured to prevent drooping of the toe (foot drop) that occurs between the heel contact with the ground and the entire sole surface of the foot during walking, and to control plantar flexion. has been done. This short leg orthosis is intended to help keep the toes from drooping when walking, allowing the user to step forward without getting the toes caught on the floor.

Patent No. 4156909

The biomechanical characteristics of the lower limbs during walking on a horizontal surface include a stance phase, a forward swing phase, and a swing phase, which are said to be repeated in this order. The stance phase is initiated by heel contact, and the swing phase is initiated by toe liftoff. The preswing phase is a period in which the upper leg swings out and the knee bends prior to the transition from the stance phase to the swing phase. During this front swing phase, the heel leaves the ground due to the weight shift, and a kicking motion is performed with the tip of the foot.

In the short leg orthosis described in Patent Document 1, plantar flexion is dampened when the heel strikes the ground during the stance phase, but no consideration is given to foot movement during the pre-swing phase. When walking is difficult due to a motor disorder, the force of this push-off motion is likely to be weak, and the pre-swing phase is considered to be important for stable walking. Therefore, in order to more effectively assist walking movements using this type of short leg orthosis, it is desirable to have not only the above-mentioned plantar flexion dampening function, but also a plantar flexion assist function that assists push-off during the pre-swing phase.

Further, since it is assumed that the foot to which the short leg orthosis is attached is worn with shoes, the short leg orthosis is preferably compact and lightweight.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide both a plantar flexion braking function to suppress foot drop and a plantar flexion assisting function when kicking off. The purpose of the present invention is to provide a short leg orthosis that is compact and lightweight, and which more effectively assists walking motion.

The solution of the present invention to achieve the above object includes: a shin-side fixing member attached to the shin; a foot-side fixing member attached to the foot; the shin-side fixing member and the foot-side fixing member. The premise is a short leg orthosis having a connecting member that connects the foot side fixing member, and the connecting member supports the foot side fixing member so as to be capable of plantar dorsiflexion with respect to the shin side fixing member, and the foot side fixing member A plantar flexion braking section that brakes plantar flexion and a plantar flexion biasing section that biases the foot side fixing member in a direction from dorsiflexion to the plantar flexion direction, the plantar flexion braking section controlling the normal position of the foot side fixing member. The plantar flexion biasing portion includes a first member that provides resistance to displacement in the plantar flexion direction from the foot side fixing member, and the plantar flexion biasing portion resists the displacement of the foot side fixing member in the dorsiflexion direction from the normal position. It is characterized by including a second member that applies a biasing force.

Furthermore, the plantar flexion braking section may be configured to further provide a restoring force to return the foot-side fixing member from plantar flexion to a normal position.

With these specific items, both the plantar flexion braking function by the plantar flexion braking part and the plantar flexion assisting function by the plantar flexion urging part are combined, and foot drop is suppressed, and the plantar flexion during kickoff is suppressed. Bending is assisted, making it possible to more effectively assist walking motion.

More specific configurations of the short leg orthosis include the following. That is, the plantar flexion damping section preferably includes a viscous damper having a cylinder rod filled with a viscous fluid as the first member. The plantar flexion damping section may further include a compression spring through which the cylinder rod passes. This allows the plantar flexion damping section, which applies resistance to displacement of the foot side fixing member from its normal position in the plantar flexion direction, to function sufficiently with a simple structure.

Further, in the short leg orthosis, it is preferable that the plantar flexion biasing section includes a compression spring as the second member. Thereby, the plantar flexion biasing portion that biases the foot-side fixing member from the dorsiflexion direction to the plantarflexion direction can function sufficiently with a simple structure.

Moreover, it is preferable that the plantar flexion braking part and the plantar flexion urging part are arranged in series so that the operating direction is common. Thereby, the plantar flexion braking section and the plantar flexion urging section can function efficiently and can be provided in the short leg orthosis in a compact manner.

In the ankle-foot orthosis, the first member and the second member may be made of an elastomer. This makes it possible to reduce the size and weight of the ankle-foot orthosis.

According to the present invention, a short leg orthosis can be provided with both a plantar flexion braking function to suppress foot drop and a plantar flexion assisting function when kicking off, thereby more effectively assisting walking movements. It becomes possible to do so.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing the short leg orthosis according to Embodiment 1 of the present invention, seen from the outside of the short leg. FIG. 2 is a side view showing the opposite side of the short leg orthosis of FIG. 1; FIG. 2 is a side view of the short leg orthosis of FIG. 1 when viewed from the rear side of the foot. 4(a) and 4(b) are enlarged views of a part of the connecting member and the storage section in the short leg orthosis, and FIG. 4(a) is a side view of the short leg seen from the outside, and FIG. b) is a side view seen from the rear side of the foot. It is an explanatory view showing typically the internal structure of the storage part in the short leg orthosis. It is an explanatory view showing operation of the short leg orthosis. It is an explanatory view showing other operations of the short leg orthosis. It is a side view which shows the short leg orthosis based on Embodiment 2 of this invention. FIG. 2 is a perspective view of the short leg orthosis seen diagonally from behind. FIGS. 10(a) to 10(c) are explanatory diagrams sequentially showing foot movements during the stance phase of the walking cycle.

Before explaining the short leg orthosis according to the embodiment of the present invention, the movement of the foot during walking will be outlined. The elements of gait can be explained by the gait cycle, and the series of movements from heel contact to ipsilateral heel contact can be broadly divided into stance phase and swing phase. Hereinafter, the period starting from heel contact and ending with toe-off will be referred to as the stance phase, and the period starting from toe-off and ending with heel contact will be referred to as the swing phase.

FIGS. 10(a) to 10(c) are explanatory diagrams showing the movement of one leg (short leg) 100 during the stance phase. 10(a) shows the "heel contact period" which is the initial stage of the stance phase, FIG. 10(b) shows the "mid stance period" when the entire foot is in contact with the ground, and FIG. 10(c) shows the "heel contact period" which is the initial stage of the stance phase. This shows the ``foreleg swing phase,'' which is the later stage of the period.

The heel-striking phase is part of the stance phase, starting with the heel touching the ground at the beginning of stance and ending with the toe touching the ground. The mid-stance phase is part of the stance phase, starting with the toe touching the ground and ending with the heel touching the ground. The pre-swing phase is part of the stance phase, starting with the toe touching the ground and ending with the heel touching the ground, before the transition to the swing phase in the late stance phase, during which the upper leg swings in the walking direction and the knee joint bends, ending with the heel off the ground and the toe off the ground. During this pre-striking phase, the opposite foot is in the stance phase after the initial contact.

During the heel-contact phase shown in Figure 10(a), plantar flexion occurs, bending the toes in a downward direction. During the mid-stance phase shown in Figure 10(b), the weight shifts forward, the shin begins to lean forward, and dorsiflexion occurs, bending the toes in a upward direction. During the front leg swing phase shown in Figure 10(c), plantar flexion occurs again as the toes push off. In the figure, arrow A, which indicates the direction of toe movement, indicates the force in the plantar flexion direction, arrow B indicates the force in the dorsiflexion direction, and arrow C indicates the force in the plantar flexion direction. Furthermore, plantar flexion and dorsiflexion, which are the movements during the stance phase, are collectively referred to as plantar and dorsiflexion.

(Embodiment 1)
A short leg orthosis 1 according to Embodiment 1 will be described with reference to the drawings.

1 to 3 show a short leg orthosis 1 according to a first embodiment, FIG. 1 is a side view of the short leg orthosis 1, FIG. 2 is a side view showing the opposite side of FIG. 1, and FIG. 3 is a side view of the short leg orthosis 1. FIG. 2 is a side view seen from the rear side of the foot in FIG. 1; In addition, FIG. 1 shows the short leg orthosis 1 when worn on the left foot as seen from the outside of the short leg, FIG. 2 shows it as seen from the inside of the short leg, and FIG. 3 shows it as seen from the rear side of the foot (heel side). There is. The right-left direction, front-back direction, and up-down direction in the explanation are shown based on the foot on which the foot is worn. When worn on the right leg, the short leg orthosis 1 appears symmetrical to these drawings.

The short leg orthosis 1 includes a shin-side fixing member 2 attached to the shin, a foot-side fixing member 3 attached to the foot, and a connection that connects the shin-side fixing member 2 and foot-side fixing member 3. It is configured to include a member 4.

- Shin-side fixing member The shin-side fixing member 2 is attached to the shin below the knee and supports the lower leg. In the illustrated form, the shin-side fixing member 2 includes a shin attachment part 21 that is applied to the front of the shin (front surface of the lower leg), and a shin belt 22 that fixes the shin attachment part 21 to the shin. The shin attachment part 21 is an elastic band-like member, and is formed in a rounded curved shape along the shin part. The shin belt 22 is a band-shaped belt extending from one end of the shin attachment part 21 to the other end, and is disposed on the rear surface of the lower leg (calf). The shin belt 22 is secured to the shin by a suitable length-adjustable fastening means such as a hook-and-loop fastener.

- Foot-side fixing member The foot-side fixing member 3 is a member on which the foot, which is the part below the ankle, is placed. A foot belt 32 for fixation is provided. In the illustrated form, the sole plate portion 31 has a shape in which the center portion gently bulges upward so as to follow the arch of the sole of the foot. The foot belt 32 is a belt-shaped belt extending from one side edge of the sole plate portion 31 in the width direction (left-right direction) to the other side edge, and is arranged along the dorsum of the foot. The foot belt 32 is fixed to the foot by an appropriate length-adjustable fastening means such as a hook-and-loop fastener.

The shin attachment portion 21 of the shin side fixing member 2 and the base plate portion 31 of the foot side fixing member 3 have a certain rigidity and can be individually manufactured to fit the size and shape of the foot. They can be made from thermoplastic resins such as polyethylene, polypropylene, Teflon (registered trademark), and ABS resin, or thermosetting resins such as epoxy resin, unsaturated polyester resin, and thermosetting polyimide.

- Connecting Member The connecting member 4 is a member that supports the foot-side fixing member 3 with respect to the shin-side fixing member 2 so as to be capable of plantar dorsiflexion. As shown in FIG. 3, the connecting members 4 are disposed between the shin-side fixing member 2 and the foot-side fixing member 3, on the outside of the short leg and on the inside of the short leg, respectively.

Each connecting member 4 includes a rotating part 43 that rotatably supports the foot-side fixing member 3, a first connecting member 41 that connects the shin-side fixing member 2 and the rotating part 43, and a rotating part 43. It has a second connecting member 42 that connects the foot side fixing member 3.

The first connecting member 41 has an upper end connected to the front side of the shin-side fixing member 2, is bent rearward at an intermediate portion in the vertical direction, and a lower end connected to the rotating part 43. The rotating part 43 has the same height as the lateral malleolus (lateral malleolus) and corresponds to the outside of the short leg, or has the same height as the medial malleolus (inside malleolus) and corresponds to the inside of the short leg. It is placed in a position where The second connecting member has an upper end connected to the rotating part 43, and a lower end connected to the edge of the bottom plate part 31 and approximately at the center.

As shown in FIG. 1, of the two connecting members 4, the connecting member 4 disposed on the outer side of the short leg is equipped with an actuator unit 5.

4(a) and 4(b) show the actuator unit 5. FIG. 4(a) is a side view seen from the outside of the short leg, and FIG. 4(b) is a side view seen from the rear side of the leg. be. FIG. 5 is an explanatory diagram schematically showing the internal structure of the storage section 51 of the actuator unit 5. As shown in FIG. In FIG. 5, regarding the operating direction X of the plantar flexion braking section 6 and the plantar flexion urging section 7, the direction in which the actuator unit 5 is compressed toward the shin region is defined as an upward direction X1, and the direction in which the actuator unit 5 is extended toward the foot region is defined as an upward direction X1. The direction in which the image is displayed is indicated as downward X2.

The actuator unit 5 includes a storage section 51 in which a plantar flexion braking section 6 and a plantar flexion urging section 7 as actuators are housed, an output link section 52, a first mounting plate 55 and a second mounting plate joined to the connecting member 4. It has a mounting plate 56. The first mounting plate 55 is joined to the first connecting member 41 and is displaced together with the first connecting member 41 . Further, the second mounting plate 56 is joined to the second connecting member 42 and is displaced together with the second connecting member 42 .

The storage portion 51 is integrally provided with a first mounting plate 55 and is fixed to the first connecting member 41 via the first mounting plate 55. A second rod 73 extends from the lower side X2 of the storage portion 51 and is connected to the link rod 53 and the connecting portion 54 that constitute the output link portion 52.

The connecting portion 54 has a shape that projects backward from the rotating portion 43 and is formed integrally with the second mounting plate 56 . The second mounting plate 56 is joined and fixed to the second connecting member 42 and is displaced together with the second connecting member 42 together with the connecting portion 54 .

- Plantar flexion braking section As shown in FIG. 5, the plantar flexion braking section 6 is housed in the storage section 51. The plantar flexion braking unit 6 includes a first member 61 that provides resistance to displacement of the foot side fixing member 3 from its normal position in the plantar flexion direction, and brakes plantar flexion of the foot side fixing member 3 .

Here, the steady position of the foot-side fixing member 3 refers to the position when no external force is applied to the foot-side fixing member 3, and as shown in FIGS. 1 and 2, it is in the mid-stance phase of the walking cycle. This refers to the posture of the foot-side fixing member 3 with respect to the connecting member 4 when it is in a tilted state where the entire body can touch the ground. Note that the normal position of the foot-side fixing member 3 can be adjusted individually depending on the user of the short leg orthosis 1.

The plantar flexion damper 6 includes a viscous damper 62 filled with viscous fluid as a first member 61 that provides resistance to displacement in the plantar flexion direction from a normal position. The viscous damper 62 is configured such that a cylinder 63 partitioned by a cylinder wall 631 is filled with a viscous fluid such as air or oil. Inside the cylinder 63, a first rod 64, which is a cylinder rod, is provided with a piston 641 that reciprocates within the cylinder 63 along the operating direction X while forming a small gap with the inner wall of the cylinder 63. ing. The inside of the cylinder 63 is partitioned by a piston 641.

When the first rod 64 is displaced upward X1 with respect to the cylinder 63, the piston 641 moves upward X1 within the cylinder 63 while resisting the viscous fluid. This causes the viscous damper 62 to generate viscous resistance.

The plantar flexion damping section 6 further includes a first compression spring 65 through which a first rod 64 passes, located below the viscous damper 62 at X2. The first rod 64 includes a brim-shaped movable part 642 at the end opposite the piston 641. As the piston 641 moves within the cylinder 63, the first compression spring 65 expands and contracts between the movable part 642 and the cylinder wall 631.

When the first rod 64 moves upward X1 in the viscous damper 62, the first compression spring 65 is pressed by the movable portion 642 of the first rod 64 and contracts. When the pressure of the viscous damper 62 is released, the first compression spring 65 expands and presses the movable part 642, pushing it downward X2.

A collar-shaped pressing portion 731 provided at the upper end of the second rod 73 is in contact with the movable portion 642 of the first rod 64 . A lower end portion of the second rod 73 is rotatably connected to one end portion of the link rod 53. The other end of the link rod 53 is rotatably connected to a connecting portion 54 that is integral with the second mounting plate 56 . Thereby, the displacement of the second connecting member 42 fixed to the bottom plate portion 31 is transmitted to the first rod 64 via the second rod 73.

- Plantar flexion biasing section The storage section 51 further stores a plantar flexion biasing section 7 that biases the foot-side fixing member 3 from dorsiflexion to the plantarflexion direction. The plantar flexion biasing section 7 includes a second member 71 that applies a biasing force in the plantar flexion direction against the displacement of the foot-side fixing member 3 from its normal position to dorsiflexion. In the illustrated form, the plantar flexion biasing portion 7 includes a second compression spring 72 as the second member 71 .

As shown in FIG. 5, the second compression spring 72 is disposed between the pressing portion 731 and the housing inner wall 511, with the second rod 73 passing through it. The second rod 73 is connected to the second connecting member 42 via the link rod 53 of the output link section 52 and the connecting section 54 . Thereby, the displacement of the second connecting member 42 fixed to the bottom plate portion 31 is transmitted to the second rod 73.

When the second rod 73 moves downward X2, the second compression spring 72 is pressed by the pressing portion 731 and contracts. When the pressure is released, the contracted second compression spring 72 expands and pushes the pressing portion 731 upward X1. Thereby, the second rod 73 is displaced upward X1.

6 and 7 are explanatory diagrams showing the operation of the short leg orthosis 1 when walking while wearing the short leg orthosis 1.

From the swing period to the heel contact period, as shown in FIG. 6, the foot-side fixing member 3 is displaced from the normal position in the plantar flexion direction. Plantar flexion of the foot-side fixing member 3 causes the second connecting member 42 to rotate, and the sole plate portion 31 assumes a forward-inclined posture. At this time, as shown in FIG. 5, the second connecting member 42 rotates in the Y1 side of the rotation direction Y, so that The first rod 64 of the bending brake part 6 is displaced upward X1. The viscous damper 62 contracts and generates viscous resistance. Thereby, viscous resistance is applied to the rotation of the second connecting member 42 toward the Y1 side, and the rotational movement is suppressed. As a result, the plantarflexion braking unit 6 generates a resistance force and brakes the displacement of the foot-side fixing member 3 in the plantarflexion direction, suppressing excessive foot drop and enabling smooth heel contact.

When the foot enters the mid-stance phase after passing through the heel contact period, the foot-side fixing member 3 returns to its normal position, as shown in FIG. At this time, due to the expansion action of the first compression spring 65 of the plantar flexion braking unit 6, the viscous damper 62 expands and the second rod 73 is pressed downward X2. The plantar flexion braking section 6 provides a restoring force to return the foot-side fixing member 3 to a normal position, allowing a smooth transition to the mid-stance phase.

When the body enters the forward swing phase after passing through the mid-stance phase, the weight shifts toward heel-off, causing the shin to tilt forward. As shown in FIG. 7, the foot-side fixing member 3 is displaced from its normal position in the dorsiflexion direction. At this time, as shown in FIG. Displaced to. In the plantar flexion biasing portion 7, the second compression spring 72 is compressed by being pressed by the pressing portion 731 of the second rod 73. The second connection member 42 is biased in the Y1 direction by the contraction of the second compression spring 72, and when the heel lifts off, a biasing force in the plantar flexion direction is applied to the foot side fixing member 3. The foot-side fixing member 3 is applied with a biasing force in the direction of plantar flexion, making it easier to return to the normal position, and as a result, kicking off from the heel is assisted, allowing a smooth transition to the front swing phase. becomes possible.

Therefore, by walking while wearing the short leg orthosis 1, the plantar flexion braking section 6 suppresses foot drop and exhibits the plantar flexion braking function, and the plantar flexion urging section 7 assists in kicking off. It can also function as a plantar flexion assisting function.

Further, the plantar flexion braking section 6 and the plantar flexion urging section 7 are fixed to the first connecting member 41 via the storage section 51, and are arranged in series so that the operating direction X is common. Therefore, the plantar dorsiflexion of the foot-side fixing member 3 is smoothly transmitted to the second rod 73 and the first rod 64 via the link rod 53, and the plantarflexion braking section 6 and the plantarflexion urging section 7 are efficiently transmitted. can be activated. Furthermore, by arranging these in series in the storage portion 51 and integrally providing the connecting member 4, the plantar flexion braking portion 6 and the plantar flexion urging portion 7 can be formed compactly, and the actuator It becomes possible to reduce the size and weight of the unit 5. Therefore, not only flat walking while wearing the short leg orthosis 1, but also going up and down stairs and walking with shoes on are less likely to be affected, making it possible to provide effective walking assistance.

(Embodiment 2)
The ankle foot orthosis according to the present invention is not limited to the configuration shown in the first embodiment, and can be embodied in various other configurations.

FIG. 8 is a side view showing the short leg orthosis 10 according to the second embodiment, and FIG. 9 is a perspective view of the short leg orthosis 10 viewed diagonally from behind. Note that FIG. 8 shows the short leg orthosis 10 when worn on the right leg, viewed from the outside of the short leg, and FIG. 9 shows the short leg orthosis 10 seen from the diagonally rear side of the outside of the short leg. 20, a foot-side fixing member 30, and a connecting member 40 that connects them, and is common to the short leg orthosis 1 according to the first embodiment in that it includes a plantar flexion braking part 60 and a plantar flexion urging part 70. However, since the shape of each of these parts and the structure unique to the plantar flexion braking section 60 and the plantar flexion urging section 70 are unique, the explanation that overlaps with the first embodiment will be omitted, and the explanation will mainly be given to the second embodiment. The unique configuration will be explained.

As shown in FIG. 8, the shin side fixing member 20 includes a shin attachment portion 210 and a shin belt 220 that fixes the shin attachment portion 210 to the shin. The foot side fixing member 30 includes a base plate portion 310 and a foot belt 320 that fixes the base plate portion 310 to the foot.

The sole plate portion 310 is formed by being divided into a toe side and a heel side, which are connected via a hinge portion 330. The hinge portion 330 is configured such that the toe portion of the sole plate portion 310 can be bent only in the dorsiflexion direction. Since the sole plate portion 310 is rotatable in the dorsiflexion direction on the toe side, it is bent in the dorsiflexion direction along the toe during the front swing phase, and can be kicked off smoothly.

The connecting member 40 is flexible and supports the foot side fixing member 30 so that it can be dorsiflexed and plantarflexed. The shin side fixing member 20 and the foot side fixing member 30 are integrally provided at both ends of the connecting member 40. In the illustrated embodiment, the connecting member 40 is provided integrally and continuously from the lower part of the shin attachment part 210 to the heel side of the base plate part 310.

As shown in FIG. 9, the connecting member 40 extends from the outside of the short leg to the posterior surface of the crus and the heel, and is arranged in a semi-spiral shape. In addition, at least the inner surface of the connecting member 40 has a curved shape that fits the posterior surface of the crus and the heel.

The shin attachment part 210, the base plate part 310 and the connecting member 40 integrated therewith are preferably formed from a thermoplastic resin, such as polypropylene resin or polyethylene resin. The base plate part 310 and the connecting member 40 integrated therewith may also be formed as a fiber-reinforced resin molded product in which reinforcing fibers, such as short carbon fibers, are oriented and dispersed, for example, to have higher strength. The shin attachment part 210 of the shin side fixing member 20, the base plate part 310 of the foot side fixing member 30 and the connecting member 40 can be individually manufactured to suit the size and shape of the user's foot.

The connecting member 40 includes a plantar flexion braking section 60 that brakes plantar flexion of the foot side fixing member 30, and a plantar flexion urging section 70 that urges the foot side fixing member 30 from dorsiflexion to the plantar flexion direction. . The plantar flexion braking unit 60 in the second embodiment includes a first band-shaped member 610 made of elastomer as a first member 61 that provides resistance to displacement of the foot-side fixing member 30 in the plantar flexion direction. The first strip member 610 is more preferably formed of a low resilience elastomer.

As shown in FIG. 8, the first band-like member 610 is provided on the lower side of the connecting member 40 and on the side of the Achilles tendon (above the heel). In the illustrated embodiment, the upper end of the first strip member 610 is connected to the outer surface of the connecting member 40, and the lower end is connected to the outer edge of the bottom plate portion 310 of the foot-side fixing member 30.

The first band-shaped member 610 is installed obliquely from the connecting member 40 to the base plate portion 310 so as to pass through the lateral malleolus of the foot wearing the ankle-foot orthosis 10. The first band-shaped member 610 provides resistance to the displacement of the foot-side fixing member 30 from its normal position in the plantar flexion direction due to its elasticity, thereby suppressing excessive foot drop and enabling smooth heel contact. In addition, the first band-shaped member 610 provides a restoring force to the foot-side fixing member 30 by its contraction action, returning it from plantar flexion to its normal position.

The plantar flexion biasing section 70 includes a second band-shaped member 710 made of elastomer as the second member 71 that applies a biasing force in the plantar flexion direction to the foot side fixing member 30. More preferably, the second band-shaped member 710 is made of a hard elastomer. Note that the second band-shaped member 710 may be made of a hard material such as a metal leaf spring instead of an elastomer.

As shown in FIG. 9, the second band member 710 as the second member 71 is provided on the lower side of the connecting member 40 and below the rear surface of the lower leg (above the heel). In the illustrated form, the upper end of the second band-shaped member 710 is connected to the outer surface of the connecting member 40, and the lower end is connected to the back surface of the sole plate portion 310 of the foot-side fixing member 30 (the outer surface of the heel portion).

The second band-shaped member 710 is attached to the outer surface of the connecting member 40 so as to pass from the Achilles tendon to the heel of the foot on which the short leg orthosis 10 is attached. Due to its elasticity, the second band-shaped member 710 applies a biasing force in the plantarflexion direction against the displacement of the foot-side fixing member 30 from its normal position in the dorsiflexion direction. Therefore, the foot-side fixing member 30 easily returns to its normal position due to the biasing force in the plantar flexion direction by the second band-shaped member 710, thereby assisting in kicking off from the heel and smoothly transitioning into the front swing phase. enable you to migrate.

Further, the connecting member 40 is formed integrally with the shin attachment part 210 of the shin side fixing member 20 and the bottom plate part 310 of the foot side fixing member 30, and includes a first member 61 and a second member 71 made of elastomer. Because of this structure, the overall structure is compact and it is possible to significantly reduce the weight. Therefore, not only flat walking with the short leg orthosis 10 attached, but also climbing up and down stairs and walking with shoes on are less likely to be affected, making it possible to provide effective walking assistance.

As explained above, the short leg orthoses 1 and 10 have both a plantar flexion braking function that suppresses excessive foot drop during the heel contact period and a plantar flexion assist function that assists in kicking off during the front swing phase. This makes it possible to assist walking motion more effectively. In addition, in the short leg orthosis 1, 10, the plantar flexion braking parts 6, 60 having a plantar flexion braking function and the plantar flexion urging parts 7, 70 having a plantar flexion assisting function are formed compactly, making it compact and lightweight. Therefore, even if shoes are worn on the feet fitted with the short leg orthosis 1, 10, walking is not affected and stable walking is enabled.

Note that the short leg orthosis 1, 10 is not limited to the configuration shown in the embodiment described above, and can be implemented in various other forms. For example, in the short leg orthosis 1 according to the first embodiment, similarly to the second embodiment, the foot side fixing member 3 has a hinge part that can bend the bottom plate part 31 only in the dorsiflexion direction, and the bottom plate part The toe side of 31 may be rotatable in the dorsiflexion direction.

The technical scope of the present invention shall not be interpreted solely by the above embodiments, but shall be based on the claims. Further, the technical scope of the present invention includes all changes within the meaning and scope equivalent to the scope of the claims.

This invention can be used effectively as a short leg brace to assist walking.

1, 10 Ankle foot brace 2, 20 Shin side fixing member 21, 210 Shin attachment section 22, 220 Shin belt 3, 30 Foot side fixing member 31, 310 Bottom plate section 32, 320 Foot belt 4, 40 Connecting member 41 First connecting member 42 Second connecting member 43 Rotating section 5 Actuator unit 51 Storage section 52 Output link section 53 Link rod 54 Connection section 55 First mounting plate 56 Second mounting plate 6, 60 Plantar flexion damping section 61 First member 62 Viscous damper 63 Cylinder 64 First rod 65 First compression spring 610 First band-shaped member 7, 70 Plantar flexion biasing section 71 Second member 72 Second compression spring 73 Second rod 710 Second band-shaped member

Claims (5)

A short leg brace having a shin side fixing member attached to a shin portion, a foot side fixing member attached to a foot portion, and a connecting member connecting the shin side fixing member and the foot side fixing member,
The foot side fixing member is
A bottom plate portion on which the entire sole of the foot rests;
A belt-like foot belt extends from one side edge of the bottom plate to the other side edge of the bottom plate and is disposed along the instep of the foot to fix the foot to the bottom plate.
the connecting member includes a pivot portion that pivotally supports the foot side fixing member, a first connecting member that connects the shin side fixing member and the pivot portion, and a second connecting member that connects the pivot portion and the foot side fixing member, and supports the foot side fixing member in a plantar and dorsiflexible manner relative to the shin side fixing member;
A storage section fixed to the first connecting member stores a plantar flexion damping section that dampens plantar flexion of the foot side fixing member and a plantar flexion biasing section that biases the foot side fixing member from a dorsiflexion direction to a plantar flexion direction,
The plantar flexion damping portion is
a viscous damper having a cylinder rod and filled with a viscous fluid ;
a first compression spring through which the cylinder rod passes;
a resistance force is applied to the displacement of the foot side fixing member from the normal position in the plantar flexion direction , and a restoring force is applied to the displacement of the foot side fixing member from the plantar flexion to the normal position, the restoring force returning the foot side fixing member to the normal position;
the plantar flexion biasing portion includes a second compression spring that applies a biasing force in a plantar flexion direction against displacement of the foot side fixation member from a normal position in a dorsiflexion direction,
The resistance force, the restoring force, and the biasing force are transmitted to the foot side fixing member via the second connecting member which rotates around the rotating part . The short leg orthosis according to claim 1 ,
The plantar flexion braking part and the plantar flexion urging part are connected to the second connecting member via a link rod,
A short leg orthosis, wherein plantar dorsiflexion of the foot-side fixing member is transmitted to the plantarflexion braking section or the plantarflexion urging section via the link rod. The short leg orthosis according to claim 1 or 2 ,
A short leg orthosis, wherein the plantar flexion braking part and the plantar flexion urging part are arranged in series so that their operating directions are common. The short leg orthosis according to any one of claims 1 to 3 ,
The bottom plate portion has a bulge that fits along the arch of the sole of the foot,
The second connecting member has an upper end connected to the rotating portion and a lower end connected to the bulge at a side edge of the base plate portion. The short leg orthosis according to any one of claims 1 to 4 ,
The short leg orthosis is characterized in that the foot-side fixing member has a hinge portion that can be bent only in the dorsiflexion direction.

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