FR3111791A1 - FOOT / ANKLE JOINT ASSISTANCE DEVICE - Google Patents

Abstract

The present invention relates to a foot/ankle joint assist device comprising a foot support (1). Characteristically, according to the invention, it comprises a leg guide (5) of which a first end is capable of being fixed on the leg of a user, the foot support comprises at least one sole portion (10) capable to be brought into contact with the underside of the user's foot, the second end (51) of said leg guide (5) is rotatably mounted around a first axis (3), parallel to the width of said foot support (1), said first pin (3) is located above said sole portion (10), in particular at the level of the user's ankle when the device is mounted on the latter's leg, said device comprises first return means (9) arranged so as to push said leg guide (5) towards said sole portion (10), said device also comprises means (7, 13; 91, 17) for limiting the amplitude rotation of said leg guide (5) about said first axis of rotation (3) and said limiting means ( 7, 13; 91, 17) allow the adjustment of the amplitude of the rotation of said leg guide (5) around said first axis (3). FIG. 1

Description

FOOT/ANKLE JOINT ASSIST DEVICE

This application relates to a foot/ankle joint assist device.

The equine foot is a congenital pathology that requires fitting with an orthosis. In this pathology, the foot does not form a right angle with the leg. Foot drop, which is a similar pathology, can be of neurological origin or the result of a fall or prolonged immobilization. Also in this pathology, the muscles do not allow the foot to be held at a right angle to the leg. In addition, there are other pathological conditions, such as tendonitis, for example, where the foot cannot position itself at a right angle with the leg without causing pain.

Document CN 110236752 A1 describes an orthosis for the treatment of equinus foot or foot drop. This document describes a device which comprises a foot support which comprises a ring in which the end of the foot is threaded. A rotary motor is attached to the patient's calf. A cable equipped with a spring connects the ring of the foot support to the rotary motor and makes it possible to raise the end of the foot by winding the cable around an axis set in rotation by the rotary motor. This device therefore makes it possible to gently place the foot at a right angle to the leg and allows the patient to walk. This device is nevertheless complex due to the presence of the motor.

An object of the present invention is to propose a device for assisting the foot/ankle joint which makes it possible to impart to the ankle joint a given angle between the foot and the leg and which makes it possible to modulate this angle, depending on the pathology and/or the morphology of the patient. Such a device makes it possible to treat pathologies in which the angular position of the foot and the leg is involved.

Another object of the present invention is to provide a device as mentioned above which is comfortable and which allows and even facilitates walking, or even running, of the patient.

A foot/ankle joint assist device includes a foot support. Characteristically, it comprises a leg guide, a first end of which is capable of being fixed to the leg of a user, said foot support comprises at least one sole portion capable of being brought into contact with the underside of the user's foot. user, the second end of said leg guide is mounted for rotation about a first axis parallel to the width of said foot support, said first axis is located above said sole portion, in particular at the level of the ankle of the user when the device is mounted on the leg of the latter, said device comprises first return means arranged so as to push said leg guide towards said sole portion, said device also comprises means for limiting the amplitude of rotation of said leg guide around said first axis of rotation and said limiting means allow adjustment of the amplitude of rotation of said leg guide around said first st axis.

The first return means push said leg guide towards the sole portion when they are at rest, that is to say that the user does not exert any action on them.

The means for limiting the rotation of the leg guide relative to the foot support also allow the device to be used for walking. As the rotation is not blocked, the user can walk normally, unrolling his foot. The device does not have a motor, which makes it lighter, more robust and easier to manufacture. The first means of recall allow to exercise a rehabilitation of the muscles of the foot and the leg of the patient by lifting the foot so that it forms an almost right angle with the leg. The adjustment of the amplitude of the rotation makes it possible to adapt the device to the pathology of the patient and/or to his morphology.

The return means (first and second) are not limited according to the invention. It may be one or more helical springs with contiguous or non-contiguous coils.

The sole portion preferably has a length such that it extends at least from the heel to the metatarsal heads of the user's foot. It can also extend under the full length of the user's foot. The sole portion is rigid to avoid any risk of twisting the ankle.

Advantageously, the device of the invention further comprises means for locking the angular position of said leg guide relative to said foot support. In this case, it can be used with or without shoes and serves as a support orthosis. It is easily adaptable to the patient's pathology and its evolution.

Advantageously, the means for limiting the amplitude of the rotation of the leg guide also serve to lock the leg guide and the foot support in the angular position. According to a particularly advantageous embodiment, the means for limiting the amplitude of the rotation of the leg guide relative to the foot support comprise means for limiting the amplitude of the rotation of the leg guide towards the sole portion and means for limiting the amount of rotation of the leg guide in the direction opposite to the sole portion. By positioning the leg guide in a given position and by limiting the amplitude of the two rotations in both directions with respect to the given position, the angular position of the foot guide is thus blocked on the foot support.

According to a particular embodiment, the device of the invention further comprises a contact element which extends under said sole portion and second return means which push back said contact element when said contact element pivots towards said sole portion. In other words, at rest, the second return means separate the contact element from the foot support. The contact element is preferably arranged at least under the heel of the user or under the heel of the user. It is rigid and advantageously extends over the entire width of the user's foot in order to store a maximum of energy. It can also extend under the entire surface of the foot; it can also extend to the metatarsal heads of the foot or the metatarsal heads of the user's heel. The contact element can be rigid or elastically deformable along a given direction, in particular.

This particular embodiment makes it easier for the user to walk by lifting the foot of the latter after contact of the user's heel with the ground. The first return means also facilitate the walking of the user by bringing the foot towards the leg.

According to two particular embodiments of the contact element, it is either mounted for rotation around a second axis, parallel to the width of said sole portion or is mounted under said sole portion and is then elastically deformable in such a way forming a spring which pushes back said contact element, when said contact element pivots towards said sole portion.

When the contact element is elastically deformable, it also fulfills the function of the second return means. It advantageously extends from the zone of the portion of the sole corresponding to the metatarsal heads of the user up to the zone coming into contact with the heel of the user. At rest, the contact element is away from the sole portion. It is elastically deformable according to the height of the device, that is to say according to the direction perpendicular to the plane of the sole portion.

The contact element can be rotatably mounted on the foot support by means of an arm, which can be bent. In this embodiment, the contact element is preferably rigid (not elastically deformable). This arm is rotatably mounted on the foot support at one of its ends. This end mounted for rotation is advantageously arranged under the first return means.

The second axis is closer to said sole portion than said first axis; it is located substantially under the first axis. The distance which separates an axis from the sole portion is considered to be the minimum distance measured between the axis and a plane passing through the sole portion and parallel to the latter.

The device corresponding to the aforementioned particular embodiment may comprise means for limiting the amplitude of the rotation of said contact element around said second axis and these limiting means allow the adjustment of the amplitude of said rotation. These means make it possible to adapt the device to the patient's weight and stride.

Whatever the embodiment, the device may include means for locking said contact element in rotation and/or said second return means and/or said first return means may include a spring and means for adjusting the hardness of said spring. Adjusting the hardness of the spring makes it possible to adapt the force that the device will exert on the patient's foot to bring it back towards the leg. It also allows adaptation of the force exerted by the contact element according to the morphology of the patient (weight, in particular). Advantageously, the return means (first and/or second) then comprise a helical spring with non-contiguous turns.

According to a particular embodiment of the means for limiting the amplitude of the rotation of the leg guide around said first axis, they comprise:

- a first stopper of adjustable length mounted on the second end of said leg guide/said foot support and able to come into abutment against a first surface of said foot support/said leg guide or a first surface rigidly connected to said foot support / leg guide so as to limit and / or block the rotation of said leg guide towards said sole portion; and or

- a second stop of adjustable length mounted on said leg guide/foot support and capable of coming into abutment against a second surface of said foot support/leg guide or a second surface rigidly connected to said foot support/leg guide of so as to limit and/or block the rotation of said leg guide in the direction opposite to said sole portion.

The means for limiting the amplitude of the rotation of the contact element about said second axis may also comprise, independently of the embodiment of the means for limiting the rotation of the leg guide on the foot support:

- a first stop of adjustable length mounted on the second end of an arm, said first end of said arm being integral with the contact element, said second end of the arm being mounted for rotation about said second axis, said first stop being suitable to come into abutment against a first surface of said foot support so as to limit and/or block the rotation of said contact element in the direction of said leg guide; and or

- a second stop of adjustable length mounted on said arm and capable of coming into abutment against a second surface of said foot support so as to limit and/or block the rotation of said contact element in the direction of said sole portion.

The second surface may also be a surface rigidly bonded to the foot support.

These limiting means are easy to implement. They also allow the blocking in angular position of the leg guide and of the foot support, by the simultaneous limitation of the rotation of the leg guide towards the sole portion and the limitation of the rotation of the leg guide in the direction opposite to the sole length. They are robust; the threaded rods can be easily replaced.

The present invention also relates to a shoe that includes an insole and an outsole that includes an outsole. Characteristically, this shoe comprises the device of the invention; the sole portion is advantageously inserted into the shoe, in particular under the clean sole (inner sole) of said shoe. In this way, the device is well integrated into the shoe. The outer sole is advantageously elastically deformable.

When the device of the invention comprises a contact element, said contact element is advantageously located at least partially in the outer sole of said shoe, so as to compress the return means when the user strikes the ground with his heel. The contact element can be placed, for example, just under the outsole of the shoe.

The present invention, its characteristics and the various advantages it provides will appear better on reading the following description of three particular embodiments of the invention, presented by way of illustrative and non-limiting examples and which refers to the attached figures in which:

• The [Fig. 1] represents a partial view in partial section along a vertical plane of a first mode of the invention
• The [Fig. 2] represents a partial perspective view of a second embodiment of the invention; And
• The [Fig. 3] represents a schematic view of a third embodiment of the invention; And
• The [Fig. 4] represents a side view of a fourth embodiment of the invention.

With reference to the , a first embodiment of the present invention will now be described. There is a sectional view along a vertical plane parallel to the height of the leg guide of the device of the invention. The device comprises a foot support 1. In the example represented, the foot support 1 comprises a rigid sole 10 which extends over the entire lower surface of the user's foot, when the device is mounted on the leg and his foot. The foot support 1 comprises an ankle support portion 11 which extends along the ankle, opposite the external malleolus of the user's leg. The end 12 of the ankle support portion 11 comprises a first axis of rotation 3, which extends parallel to the width of the foot support 1. The leg guide 5 comprises an end 51 in the form of a fork; the end of the ankle portion 11 carrying the first axis 3 is inserted between the two branches of this fork. On the which is a cut, only one branch is visible. The leg guide 5 is mounted for rotation about the first axis 3 at the level of the end 51. The leg guide 5 extends vertically and comprises, opposite the end 51, a free end 54 which forms a sheath in which the user's calf can be inserted and held in position, for example by means of a tight band (not shown) around the calf or by any other fixing means.

With reference to the , the leg guide 5 is capable of rotating around the first axis 3 along the arrow F, that is to say in the direction of the foot support 1 (towards the right on the ) or in the opposite direction (to the left on the ). The end 12 of the ankle support portion 11 which carries the first pin 3 is rounded and has a surface 13 forming an abutment. The surface forming a stop 13 is arranged on the side of the ankle support portion 11 facing the length of the sole 10. A threaded rod 7 is inserted into the end 51 of the leg guide 5, in a wall connecting the two branches of the fork which allows the leg guide 5 to be mounted in rotation on the foot support 1. This threaded rod 7 is inserted into a threaded hole made in the thickness of the end 51 of the rod 5. The end of the rod 7 emerges at the level of the surface forming abutment 13. On the , the end of the threaded rod 7 does not touch the surface forming abutment 13. In this position, the rod 7 simply serves to limit the rotation of the leg guide 5 towards the sole portion 10. The limitation is obtained when due to of the rotation of the leg guide 5 around the first axis 3, the end of the threaded rod 7 will come into abutment against the surface forming a stop 13. The length of the portion of the threaded rod 7 inserted between the branches of the end 51 is adjustable by screwing more or less the threaded rod 7 into the aforementioned tapped hole. The length of the portion of the threaded rod 7 inserted between the branches of the end 51 therefore defines the amplitude of the rotation of the leg guide 5 relative to the foot support 1 as explained later. It also allows the blocking in position of the leg guide 5 on the foot support 1 as explained later.

With reference to the , the ankle support portion 11 comprises on its rear face, that is to say on its vertical face facing away from the length of the sole 10, a base 15 which extends towards the rear of the device. The base 15 is provided with a vertical pin 17. The leg guide 5 comprises a holding portion 53 which comprises a vertical passage 530. A helical spring with non-contiguous turns 9 is arranged vertically, along the longitudinal dimension of the leg guide 5 on the base 15, the pin 17 extending in the vertical passage formed by the coils of the spring 9. The holding portion 53, horizontal extends rearward of the leg guide 5, above the spring 9 A threaded rod 91 is inserted into the vertical passage 530 of this retaining portion and extends into the vertical passage created by the turns of the spring 9. A first bolt 92 mounted on the threaded rod 91 and disposed on the retaining portion 53 makes it possible to adjust the length of the portion of the rod 91 inserted into the spring 9. A second bolt 93 mounted on the threaded rod 91 and arranged under the retaining portion 53 makes it possible to compress the spring 9 more or less against the face of the support 15 on which the spring 9 p gives support. The length of the threaded rod 91 inserted in the spring 9 limits the rotation of the leg guide 5 towards the rear of the device. Indeed, when the leg guide 5 pivots towards the rear of the device (that is to say in the direction opposite to the length of the sole 10 on the ) the end of the rod 91 comes into abutment against the upper face of the stud 17, preventing the leg guide 5 from pivoting further rearward. The rod 91 also makes it possible to block the rotation of the leg guide 5 towards the rear of the device as indicated later. The spring 9 pushes the leg guide 5 towards the sole 10 of the foot support 1 so that the leg guide 5 and the foot support form a given angle, obtuse, straight or acute.

Two uses of this first embodiment will now be described in the context of the treatment of drop foot or equine foot. The treatment of these two pathologies consists in positioning the foot as much as possible at right angles to the leg without causing pain.

According to a first use, the device is fixed on the patient's leg and foot. The leg guide 5 is fixed to the patient's leg, the latter's foot resting on the sole 10. The angle formed by the sole 10 of the foot support 1 and the leg guide 5 is adjusted, then the two are locked pieces in the desired position. The angle formed by the sole 10 and the leg guide 5 can be straight or obtuse depending on the patient. For locking the two parts in position, the two parts are maintained in the desired angular position and the length of the threaded rod 7 is modified so that its end comes into abutment against the surface forming abutment 13. This limits the rotation of the leg guide 5 in the direction of the sole 10. Still in the desired angular position, the length of the portion of the threaded rod 91 inserted in the spring 9 is modified so that its end comes into abutment against the stud 17 This limits any rotation of the leg guide 5 towards the rear of the device, that is to say in the direction opposite to the sole 10. The two parts 5 and 1 are then blocked with respect to each other. other, forming an angle determined by the practitioner. The ankle support portion 11 supports the ankle and protects it from any risk of torsion. It is advantageously covered with a comfort padding which can also extend over the sole portion 10.

Adjusting the hardness of the spring 9 by means of the second nut 93 makes it possible to adjust the force with which the spring 9 will bring the patient's foot towards the leg in order to form a right or acute angle. This force exerted by the spring makes it possible to act on the muscles and tendons of the patient and to rehabilitate him so that his foot is again at a right angle with his leg.

In a second use, the leg guide 5 and the foot support 1 being blocked at a given angle, the threaded rod 7 and/or the threaded rod 91 is slightly unscrewed. The leg guide 5 can thus perform a rotation of amplitude fixed by the length of the portion of the threaded rods 7 and 91 inserted in the portion 51 and in the spring 9, respectively. The leg guide 5 can rotate around the first axis 3 towards the sole 10 until the end of the upper 7 comes into abutment against the surface forming a stop 13. Similarly, the leg guide 5 can also rotate towards the back until the end of the rod 91 touches the nipple 17. The patient then has a certain freedom of movement and the spring 9 still performs its rehabilitative function by pulling the foot support 1 towards the leg guide 5, that is to say by bringing the patient's foot towards his leg. The patient can then walk if he wears an enveloping shoe, of the lace-up type, which will hold the device of the invention in place.

With reference to the , a second embodiment will now be described. This embodiment can be used as an orthosis for the treatment of a pathology involving the angle formed by the foot and the leg. It can also be used as a device for optimizing running or walking for a patient suffering from tendonitis, for example, or for a runner without pathology. The elements in common with the first embodiment are identically referenced on the . The difference with the previous embodiment is the presence of a contact element 100, rigid, which extends under the foot support 1 and in the present case, under the part of the sole capable of coming into contact with the user's heel. The contact element 100 is a rigid plate which extends along the width of the sole 10. The contact element 100 is connected to the foot support 1 by means of a joint which includes an angled arm 110. One end of the bent arm 110 is secured to one end of the contact element 100. The other end of the bent arm 101 (the portion which extends after the bend) is rotatably mounted around a second axis of rotation 103 The axis 103 is parallel to the width of the foot support 1 and therefore to the first axis 3. The articulation which allows the rotational mounting of the angled arm 101 on the foot support 1 is similar to that which allows the mounting to rotation of the leg guide 5 on the foot support 1, as explained with reference to the . The threaded rod 107 corresponds to the threaded rod 7 of the joint between the leg guide 5 and the foot support 1. The spring 109 is mounted on a support arranged on the foot support 1. The support is equipped with a pin 117 which passes through the passage of the spring 109. The threaded rod 191 corresponds to the threaded rod 91 of the first articulation. Nuts equivalent to nuts 92 and 93 have not been shown for simplicity. The spring 109 extends substantially perpendicular to the spring 9. A passage is made in the angled arm 101 and serves as a holding portion for the threaded rod 191 which passes through the spring 109. The threaded rod 107 makes it possible to limit the rotation of the contact element 100 in the direction of the leg support 5; the threaded rod 191 makes it possible to limit the rotation of the contact element 100 around the second axis 103 in the direction of the foot support 1. The angular locking of the contact element 100 is obtained by adjusting the length of the threaded rod 107 and that of the threaded rod 191, in the same way as explained with reference to the . The spring 109 extends between the bent arm 101 and the foot support 1. The end of the bent arm 101 is mounted for rotation around the axis 103, which is mounted on the portion of the foot support 1 located under the base 12. The spring 109 pushes the angled arm 101 towards the rear of the device. Spring 109 is also a helical spring with non-contiguous coils.

The embodiment of the is intended to be integrated into a shoe.

The mode of operation of this second embodiment will be described with reference to the .

There schematically represents a third embodiment whose operation corresponds to that of the second embodiment of the invention, when the latter is integrated into a sports shoe. The elements in common with the second embodiment are referenced identically. The sole 10 is fixed in the shoe 200, under the insole 201 of the latter. The shoe 200 comprises an outer sole 203 made of elastically deformable material and an outsole 205 which covers the underside of the outer sole 203. The contact element 100 is placed in the thickness of the outer sole 203, near of the outsole 205. The sole 10 is arranged on the outer sole 203, in the shoe 200.

The operation of this embodiment will now be described with reference to the . The user slides his foot into the shoe 200 and fixes the leg guide 5 to his calf. He laces the laces of the shoe or closes it if it has other means of closure. When the user walks, his heel will first come into contact with the ground. The contact element 100 will therefore strike the ground due to the contact of the outer sole with the ground. The spring 109 will make it possible to dampen the contact with the ground then it will push the contact element 100 vertically (therefore the shoe 200), restoring the energy that it has stored during the impact with the ground. The spring 109 therefore facilitates the lifting of the user's foot by projecting the user's foot upwards. This help is invaluable in case of tendinitis, for example. The leg guide 5 assists in the positioning of the leg during walking and facilitates the rolling of the user's foot by raising the user's foot towards the leg.

With reference to the , a fourth embodiment will now be described. The elements in common with the other embodiments are referenced identically. On the , the user's leg and foot are shown. For the sake of simplicity, not all the references have been indicated on the . This fourth embodiment is different from the first embodiment in that it comprises a contact element 100 which is a blade forming a spring. This blade is fixed under the sole 10, at the level of the front portion of the latter, at least at the level of the region of the sole in contact with the metatarsal heads of the user. The rear of the blade 100 which extends towards the rear of the sole, in the direction of the user's heel, is free and distant from the underside of the sole 10. A complementary spring 110 connects the underside of the sole 10 to the rear of the blade 100. This spring 110 is placed at the level of the user's heel, therefore at the rear of the sole 10. The spring 110 is not compulsory since the blade 100 is a spring on its own. There represents blade 100 at rest.

The operation of this device will be explained with reference to the .

When the user's heel strikes the ground, the spring 110 is compressed and the blade 100 is brought closer to the underside of the sole 10. The spring 110 therefore exerts a force under the user's heel at the same time as the blade 100 The user's heel is thus propelled upwards, which facilitates his walking or running and increases the speed of the latter.

Claims (10)

Device for assisting the foot/ankle joint which comprises a foot support (1) characterized in that it comprises a leg guide (5) of which a first end (53) is adapted to be fixed on the leg of a user, in that said foot support comprises at least one sole portion (10) capable of being brought into contact with the underside of the user's foot, in that the second end (51) of said leg guide (5) is mounted for rotation about a first axis (3), parallel to the width of said foot support (1), in that said first axis (3) is located above said sole portion (10 ), in particular at the user's ankle when the device is mounted on the latter's leg, in that said device comprises first return means (9) arranged so as to push said leg guide (5 ) towards said sole portion (10), in that said device also comprises means (7, 13; 91, 17) for limiting the amplitude of rotation of said leg guide (5) about said first axis of rotation (3) and in that said limiting means (7, 13; 91, 17) allow the adjustment of the amplitude of the rotation of said leg guide (5) around said first axis (3). Device according to claim 1, characterized in that it further comprises means (7, 13; 91, 17) for locking the angular position of said leg guide (5) relative to said foot support (1) . Device according to any one of the preceding claims, characterized in that it further comprises a contact element (100) which extends under the said sole portion (10) and second return means (109) which repel said contact element (100) when said contact element (100) pivots towards said sole portion (10). Device according to Claim 3, characterized in that the said contact element (100) is mounted for rotation about a second axis (103), parallel to the width of the said sole portion (10) or in that the said contact is mounted under said sole portion and is elastically deformable so as to form a spring which pushes back said contact element, when said contact element (100) pivots towards said sole portion (10). Device according to Claim 3 or 4, characterized in that it includes means (107; 191, 117) for limiting the amplitude of the rotation of the said contact element (100) around the said second axis (103) and in that that said limiting means (107; 191, 117) allow adjustment of the amplitude of said rotation. Device according to Claim 4, characterized in that it comprises means (107; 191, 117) for locking said contact element in rotation and/or in that said second return means (109) and/or said first means reminder (9) comprise a spring and adjustment means (93) of the hardness of said spring (9; 109). Device according to any one of the preceding claims, characterized in that the said means for limiting the rotation of the said leg guide (5) around the said first axis (3) comprise:
- a first stopper (7) of adjustable length mounted on the second end (51) of said leg guide (5)/said foot support (1) and able to come into abutment against a first surface (13) of said foot support (1)/said leg guide (5) or a first surface rigidly connected to said foot support (1)/leg guide (5) so as to limit and/or block the rotation of said leg guide (5) towards said sole portion (10); and or
- a second stopper (91) of adjustable length mounted on said leg guide (5)/foot support (1) and able to come into abutment against a second surface (17) of said foot support (1)/leg guide (5) or a second surface rigidly connected to said foot support (1)/leg guide (5) so as to limit and/or block the rotation of said leg guide (5) in the direction opposite to said sole portion ( 10). Device according to any one of Claims 5 to 7, characterized in that the said means for limiting the amplitude of the rotation of the said contact element (100) about the said second axis (103) comprise:
- a first stop (107) of adjustable length mounted on the second end of an arm (101), said first end of said arm being integral with the contact element (100), said second end of the arm being mounted for rotation around of said second axis (103), said first abutment (107) being capable of coming into abutment against a first surface of said foot support (1) so as to limit and/or block the rotation of said contact element (100) in the direction of said leg guide (5); and or
- a second stopper (191) of adjustable length mounted on said arm (101) and capable of coming into abutment against a second surface (117) of said foot support so as to limit and/or block the rotation of said contact element (100 ) in the direction of said sole portion (10). Shoe characterized in that it comprises the device according to any one of the preceding claims. Shoe according to Claim 9, characterized in that the said device comprises a contact element (100) and in that the said contact element (100) is located at least partially in the outer sole (203) of the said shoe.