US20230309654A1

US20230309654A1 - Insole

Info

Publication number: US20230309654A1
Application number: US17/708,652
Authority: US
Inventors: Daniel Feldman
Original assignee: Profoot Inc
Current assignee: Tommie Copper Ip Inc
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2023-10-05
Also published as: WO2023192005A3; WO2023192005A2

Abstract

An insole having a soft, resiliently compressible cushioning urethane foam body shaped to be placed inside footwear and to lie be beneath the length and width of the user's foot; the forefoot portion having a forefoot oblong or circular domed pad which is positioned to be under an MTP-1 joint of a user to elevate and cushion the MTP-1 joint of the user by 2 mm to 4 mm thereby supinating the user's foot towards an lateral outer side of the insole. A continuous flexible and minimally compressible support shell attached to the foam body extending from along the perimeter of the insole from the medial edge of the insole from the forefoot pad back to the lateral edge of the rearfoot portion to cradle the heel. The support shell is configured to help stabilize and correct the user's foot position to more properly align the user's kneecap to reduce knee pain.

Description

FIELD

Presented herein are foot care products and more particularly insoles providing medial stability and support and supination from the heel to the ball-of-foot region to reduce user overpronation and thus useful to relieve knee pain while simultaneously providing cushioning to reduce stress impact to a person in motion.

BACKGROUND

Unless otherwise indicated herein, the materials described in this section are not prior art to the claims and are not admitted as being prior art by inclusion in this section.
Insoles, inserts, and other types of foot cushioning mechanisms are directed to the well-being of the human foot. The human foot experiences repetitive stresses from weight bearing during a variety of activities, such as walking, climbing, kicking, running, dancing, jumping and the like. Insoles accordingly provide a broad, stable base to support the foot during ground contact.
During running, for example, the heel strikes the ground followed by the ball of the foot. As the heel leaves the ground, the foot rolls forward until the toes make contact, and then the entire foot leaves the ground to begin another cycle. When the foot is in contact with the ground, it typically rolls from the outside (lateral side) to the inside (medial side). This process is referred to as pronation. Thus, the outside of the heel usually strikes first and the toes on the inside of the foot typically leave the ground last. While the foot is in the air and preparing for another cycle the opposite process, called supination, which is a rolling of the foot from the medial to the lateral side, occurs. Over-pronation, an excessive inward roll of the foot when in contact with the ground, can be a potential source of foot, knee and leg injury. Soft cushioning materials in the midsole may provide protection against impact forces, but they can also encourage instability of the subtalar joint, thereby contributing to the tendency for over-pronation. This instability has been cited as a contributor to “runner's knee” and other athletic injuries. (See, e.g., U.S. Pat. No. 5,247,742 to Kilgore)
Foam insoles are known in the art as a lightweight material to reduce and soften impact forces to the foot under stress. Foam materials typically used for insoles may be relatively soft but provide increasing instability in proportion to increasing foam thickness (See e.g., U.S. Pat. No. 9,205,615 to Maranan). For example, the use of soft insole materials, especially in the midsole portion, can protect against vertical impact stresses. However, foam insole configurations can lead to instability of the ankle, thereby contributing to the tendency for over-pronation.
Overpronation can cause discomfort to a person such as the condition chondromalacia patella, which can be a cause for knee cap pain. The patella is covered with a smooth cartilage layer, which glides across the knee when the joint is bent. The pain is caused by an irritation of the undersurface or patella of the kneecap as the kneecap rubs against one side of the knee joint, irritating the cartilage surface. Chondromalacia can occur when a person overpronates because the tibia is locked into the Talus and therefore continues to rotate internally past the end of the contact phase (where supination starts at the beginning of midstance in a normal gait) while the femur rotates externally at midstance. The resulting counter-rotation of the femur and the tibia causes the patella to rub against the medial femoral condyle instead of moving smoothly up and down in its normal track, which causes the pain felt by the patient and damage to the cartilage. Chondromalacia patellae may result from degeneration of cartilage due to poor alignment of the kneecap (patella) as it slides over the lower end of the thighbone (femur). This process is sometimes referred to as patellofemoral syndrome.
Insole design often involves a balance between stability and cushioning to reduce impact stress to the body. Recent footwear developments have resulted in relatively lightweight shoes and insoles formed of materials selected for optimum cushioning and flexibility. Despite these improvements, shoe designs continue to cause foot problems such as Achilles tendonitis, inverted heel, weak arch and excessive use of toe flexers; metatarsal stress fracture, pronatory abnormalities and forefoot problems; and runner's knee (chondromalacia) caused by conditions such as weak foot, forefoot varus, Morton's foot and pronatory foot influences including an unstable heel. (See, U.S. Pat. No. 8,784,808 to Hockerson) In one example, an athletic shoe provides midsole shock absorption and gait control. Other pronation control configurations in the heel and a portion of the arch may be found in U.S. Pat. No. 5,247,742 to Kilgore et al.; U.S. Pat. No. 5,806,209 to Crowley et al.; and U.S. Pat. No. 10,405,602 to Laframboise et al.
There is thus a desire and a need in the art for insole configurations to provide improved stability in a foam-based insole to reduce the effects of chondromalacia caused by overpronation while maintaining overall comfort and cushion in a lightweight insole.

SUMMARY

Accordingly, to advance at least the aforementioned deficiencies in the art, described herein are insoles configured to reduce knee pain, such as from chondromalacia (“Runner's Knee”).
According to one approach, an insole is provided for footwear, the insole may have a top surface for receiving a bottom of a user's foot, a bottom surface, a toe end, a heel end, an inner medial portion having a medial edge, an outside lateral portion having a lateral edge, a forefoot portion, a midfoot portion and a rearfoot portion have a rear edge; the insole may have a substantially soft, resiliently compressible cushioning urethane foam body dimensioned and shaped to be placed inside footwear and to lie be beneath the length and width of the user's foot; the forefoot portion having a forefoot oblong or circular domed pad which is positioned to be under an MTP-1 joint of a user to elevate and cushion the MTP-1 joint of the user by 2 mm to 4 mm thereby supinating the user's foot towards an lateral outer side of the insole, wherein a front end of the forefoot portion is dimensioned to be placed beneath a distal end of toes of the wearer wearing the insole; the rearfoot portion may have a rearfoot circular or oblong domed pad attached to the foam body for inclining the foot of the wearer towards the outer side of the insole; and a continuous flexible and minimally compressible support shell attached to the foam body extending from along the perimeter of the insole from the medial edge of the insole from the forefoot pad back and around the heel edge to the lateral edge of the rearfoot portion to cradle the heel, the support shell extending towards and onto the bottom surface on the medial side of the insole, wherein the support shell is configured to help stabilize and correct the user's foot position to more properly align the user's kneecap to reduce knee swelling, pain and discomfort.
According to one approach, the forefoot portion is 2.0 to 2.5 mm thick and the forefoot pad is a dome at 2 to 5 mm at its thickest point resulting in an overall thickness of 4-7.5 mm, but preferably about 2 mm and 5.5 mm respectively.
According to one approach, a velvety cloth layer is attached to the top surface of the foam body.
The support shell can be made from the group consisting of rubber, plastic material, TPU, gel, thermoplastic polyester elastomer, EVA, combinations thereof and the like.
The support shell may have a modulus of 65,000 to 130,000 psi as determined by a standard ASTM test, and a hardness in the range of 60 to 80 Shore D. The support shell may have a thickness of 2 mm.
The midfoot portion may have a raised longitudinal arch on the medial side configured and shaped to support an arch of the user.
The midfoot arch portion may be integrally formed within the midsole portion of the insole.
The support shell extends laterally along the insole bottom surface at the midfoot arch portion and the forefoot MTB-1 joint portion.
The foam body may have a hardness in the range of 30 to 80 on the Asker C scale.
Other features will become more apparent to persons having ordinary skill in the art to which the assemblies pertain and from the following description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a bottom rear perspective view of a right foot stabilizing insole according to one approach of the present embodiments, the corresponding left foot insole being a mirror image thereof;

FIG. 2 illustrates a right side (medial) elevational view of the insole of FIG. 1 ;

FIG. 3 illustrates a planar bottom view of the insole of FIG. 1 ;

FIG. 4 illustrates a left side (lateral) elevational view of the insole of FIG. 1 ;

FIG. 5 illustrates a top planar view of the insole of FIG. 1 ;

FIG. 6 illustrates a front side elevational view of the insole of FIG. 1 ;

FIG. 7 illustrates a cross-sectional view of the insole of FIG. 1 taken along section lines VII—VII of FIG. 3 ;

FIG. 8 illustrates a cross-sectional view of the insole of FIG. 1 taken along section lines VII—VII of FIG. 3 ;

FIG. 9 illustrates a cross-sectional view of the insole of FIG. 1 taken along section lines IX—IX of FIG. 3 ;

FIG. 10 illustrates a cross-sectional view of the insole of FIG. 1 taken along section lines X—X of FIG. 3 ;

FIG. 11 illustrates a front side elevational view of the insole of FIG. 1 ;

FIG. 12 is a rear bottom perspective view of a right foot insole of the present embodiments according to another approach, the corresponding left foot insole being a mirror image thereof;

FIG. 13 is a front top front perspective view of the insole of FIG. 12 ; and

FIG. 14 is a bottom right foot insole according to the present embodiments.

While the features described herein may be susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to be limiting to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the subject matter as defined by the appended claims.

DETAILED DESCRIPTION

The present insoles provide support and cushioning as well as medial posting to apply supination to a user's foot. This posting can be the result of a combination of a support shell attached to and running longitudinally along the medial length of a foam insole body. The support shell may gently stabilize and supinate foot position along its length. For example, the present insoles can elevate/supinate/post the hallux (most medial toe, “big toe”) joint (metatarsophalangeal joint, MTP1-joint) of the ball-of-foot. In the present embodiments, there can be 0.5-6 mm of medial posting, such as 2-3 mm of posting, at the MTP-1 joint relative to the other metatarsophalangeal toe joints. In the present embodiments a flexible minimally compressible support shell portion may be made of, for example, a polymer such as ethyl vinyl acetate (“EVA” or “phylon”). The EVA support shell can extend from at least the midfoot arch portion and extend to the forefoot ball-of-foot portion at the big toe joint. Providing a slightly higher portion for the MTP1-joint elevates this toe joint to reduce compression and keep the knee from collapsing.
It is noted that the term posting as used herein defines adjusting pronation and supination of the foot. Posting is a process that involves modifications to an insole by tilting certain insole portions to control motion and joint forces of a human foot while ambulating (e.g., walking, climbing, kicking, running, dancing jumping, and otherwise moving about).
The present embodiments improve the stability of the medial column by considering the plantar angles of the heel, arch and ball of foot to an intended level of control and the ranges of motion available with a goal to reduce some types of knee pain.
The midfoot portion of the present insoles are configured to provide arch support and may have a thickened portion working in combination with the support shell, also for tilting the user's midfoot toward the outer edge of the insole at the midfoot,
The heel portion of the insole has a shock absorbing domed pad, such as a gel shock stopper for the heel.1 The stabilizing and supporting shell to also create a tilt of the user's foot towards the outer edge of the insoles as well as cradle the heel for improved stability, According to one aspect, a gel shock stopper is embedded in the heel portion of the foam body portion 22 to provide a cushioned heel support and can be made from thermoplastic polyurethane (TPU) and the like (such as non-Newtonian materials) to provide comfort and shock absorption for knees.
According to one aspect, the body of the insole can be formed from a moisture management cushioning urethane foam, such as those sold under the tradename VITA-FOAM by ProFoot, Inc. The foam body is lightweight yet firm to help to support and position the foot, absorb shock and relieve aches, burning and painful clicking.
According to one aspect, the top surface may have a velvety top cloth.
The present embodiments provide a support shed incorporated into the forefoot (ball-of-foot), midfoot (arch) and rearfoot (heel) portions. As noted above, the support shell gently stabilizes the foot position to help properly align the kneecap. The support shell may be made from a single integral piece of plastic material, such as a thermoplastic polyester elastomer. The plastic material is relatively hard and substantially noncompressible. The plastic material preferably has a relatively high flex modulus, e.g. preferably 65,000 to 130,000 psi as determined by a standard ASTM test, and a hardness preferably in the range of 60 to 80 Shore D. This is in sharp contrast to the much softer foam material used in a foam sole, such as the foam body 22, which generally has a hardness in the range of 30 to 80 on the Asker C scale.
FIGS. 1-11 show an insole 20 (FIGS. 12-14 an insole 20 i) of the present embodiments configured to receive a foot having a heel portion 30, a midsole portion 32, and a forefoot portion 34. As described herein heel portion 30 of insole 20 is generally the portion of insole 20 adjacent a user's heel. The forefoot portion 34 of insole 20 generally describes the portion of the insole adjacent to the part of the foot referred as the “ball-of-foot” region, e.g., where the first to fifth metatarsophalangeal joints (MTP-1 through 5) are located. The midsole portion 32 is generally the portion of insole 20 adjacent to the arch of a user's foot.
According to the present embodiments insole 20 may have a foam body 22 to define a body of the insole. Foam body 22 may been made from a substantially soft, flexible, bendable, and resiliently compressible cushioning urethane foam body dimensioned and shaped to be placed inside footwear and to lie be beneath the length and width of the user's foot. Foam body portion 22 has a flat top surface 54, an arch 60 and a sloped ridge 52 extending the perimeter of insole 20 from the medial midsole portion edge around the heel edge and around to the lateral heel edge. Ridge 52 cradles and supports the user's arch and heel. Foam body portion 22 may have a hardness in the range of 30 to 80 on the Asker C scale. In some embodiments foam body 22 may have a velvety layer 56 applied to the top surface of the insole. Foam body 22 may also optionally have grooves 40 (FIG. 10 ).
The present embodiments also have a domed circular or oblong heel pad 24 in heel portion 30 as described herein made from shock absorbing materials such as thermoplastic polyurethane (“TPU”) or non-Newtonian material.
A support shell/medial posting (supinating) portion 26 gently stabilizes and corrects foot position while, for example while running, to supinate the foot from cradling the heel to the MTP1 joint. Support shell 26 is a continuous flexible and minimally compressible. It attaches to the foam body and extends from along the perimeter of the insole from the medial edge of the insole from the forefoot pad back and around the heel edge to the lateral edge of the rearfoot portion to cradle the heel, the support shell further extending towards and onto the bottom surface on the medial side of the insole in the arch and MTP-1 joint areas, wherein the support shell is configured to help stabilize and correct the user's foot position to more properly align the user's kneecap to reduce knee swelling, pain and discomfort.
Support shell 26 may be made from a variety of materials such as rubber, plastic material, TPU, gel, thermoplastic polyester elastomer, EVA, and the like and combinations thereof. Optional support shell grooves 38 may be added to the support shell. Support shell 26 may have a modulus of 65,000 to 130,000 psi as determined by a standard ASTM test, and a hardness in the range of 60 to 80 Shore D. The support shell may have a uniform thickness of about 1-4 mm, and in one embodiment about 2 mm (e.g., 2 mm). In an embodiment where the forefoot domed pad 28 is formed from the support shell 26, the thickness of the support shell could be from between 2 mm to 7 mm. In one embodiment this could be 5.5 mm total thickness at the thickest point of the forefoot area.
A domed circular or oblong forefoot pad 28 is provided in the forefoot portion 34 of insole 20. Forefoot pad 28 may be integral to support shell 26, integral to foam body portion 22, or made from a second material such as EVA. Forefoot pad 28 is positioned within the forefoot portion 34 of insole body portion 22 under the user's MTP-1 joint. The forefoot portion pad can be a dome at 3.0 mm at its thickest point. Accordingly, the MTP-1 joint is raised about 3 mm higher than the MTP joints 2-5 to supinate the ball of foot region of the user's foot about 3 mm.
Exemplary thicknesses are provided of the embodiment of FIGS. 1-11 to show how insole 20 supports, stabilizes and supinates the user's foot. Other variations of these measurements are possible within the scope of these embodiments. As show in the figures, measurements corresponding to the reference numbers are as follows:

- measurement 36, the thickness of the support shell portion, can be 2 mm (with a range of 1-4 mm);
- measurement 44, the forefoot foam body thickness, can be 2.5 mm (with a range of 2-3.5 mm);
- measurement 46, the thickness of insole at section lines VII and X—X, can be 16 mm (with a range of 14-18 mm);
- measurement 48, the insole thickness at section line VII-VII and VIII-VIII of FIG. 3 is 5.5 mm at the thickest point of the forefoot domed pad 28 (with a range of 4-7 mm);
- measurement 50, the insole thickness at line VII-VII the thickest point of the domed heel pad 24 can be 10.3 mm (with a range of 8-15 mm);
- measurement 58, the insole thickness at line VII-VII (See FIG. 7 ) the thickest point of the insole arch 60 can be 12.8 mm (with a range of 10-15 mm); and
- measurement 62, the support shell 26 thickness at line X-X (See FIGS. 7 and 10 ) can be 2.0 mm (with a range of 1-3 mm).

FIGS. 12-14 show an alternate approach insole 20 i to the present embodiments having a support shell 26 i, domed heel pad 24 i, foam body 22 i, sloped ridge 52 i, foam body flat top surface portion 56, and an MTP1 joint domed pad 28 i.
While the embodiments have been described in conjunction with specific embodiments, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, the present embodiments attempt to embrace all such alternatives, modifications and variations that fall within the spirit and scope of the appended claims. Throughout this specification and the drawings and figures associated with this specification, numerical labels of previously shown or discussed features may be reused in another drawing figure to indicate similar features.

LIST OF REFERENCE NUMBERS

- 20 insole
- 22 foam body
- 24 heel pad
- 26 support shell/medial posting portion
- 28 forefoot pad (EVA integral to support shell or TPU)
- 30 heel portion
- 32 midsole portion
- 34 forefoot fortion
- 36 thickness of forefoot portion of support shell stabilizing portion 26
- 38 support shell portion grooves about 0.5-2 mm deep (optional)
- 40 foam body grooves (FIG. 10 )
- 42 forefoot pad spacer (e.g., 0.5 mm)
- 44 insole foam thickness at section line VII-VII and VIII-VIII (e.g., 2.5)
- 46 heel portion thickness (e.g., 16.0 mm)
- 48 overall domed forepad thickness at its thickest point (e.g., 5.5 mm)
- 50 heel pad thickness at section line X—X (e.g., 10.3 mm)
- 52 sloped ridge around heel portion perimeter
- 54 flat top insole surface foot portion
- 56 velvety top surface
- 58 arch height (e.g., 12.5 mm)
- 60 arch
- 62 support shell thickness (e.g., 2.0 mm)

Claims

I claim:

1. An insole for footwear, comprising:

the insole having a top surface for receiving a bottom of a user's foot, a bottom surface, a toe end, a heel end, an inner medial portion having a medial edge, an outside lateral portion having a lateral edge, a forefoot portion, a midfoot portion and a rearfoot portion have a rear edge;

the insole having a substantially soft, resiliently compressible cushioning urethane foam body dimensioned and shaped to be placed inside footwear and to lie be beneath the length and width of the user's foot;

the forefoot portion having a forefoot oblong or circular domed pad which is positioned to be under an MTP-1 joint of a user to elevate and cushion the MTP-1 joint of the user by 2 mm to 4 mm thereby supinating the user's foot towards an lateral outer side of the insole, wherein a front end of the forefoot portion is dimensioned to be placed beneath a distal end of toes of the wearer wearing the insole;

the rearfoot portion having a rearfoot circular or oblong domed pad attached to the foam body for inclining the foot of the wearer towards the outer side of the insole; and

a continuous flexible and minimally compressible support shell attached to the foam body extending from along the perimeter of the insole from the medial edge of the insole from the forefoot pad back and around the heel edge to the lateral edge of the rearfoot portion to cradle the heel, the support shell extending towards and onto the bottom surface on the medial side of the insole, wherein the support shell is configured to help stabilize and correct the user's foot position to more properly align the user's kneecap to reduce knee swelling, pain and discomfort.

2. The insole of claim 1, wherein the rearfoot portion pad is made from a thermoplastic polyurethane or a non-Newtonian material.

3. The insole of claim 1, wherein the forefoot portion is 2.0 to 2.5 mm thick and the forefoot pad is a dome at 2-5 mm at its thickest point resulting in an overall thickness of 4-7.5 mm.

4. The insole of claim 1, further comprising a velvety doth layer attached to the top surface of the foam body.

5. The insole of claim 1, wherein the support shell is made from the group consisting of Rubber, plastic material, TPU, gel, thermoplastic polyester elastomer, and EVA.

6. The insole of claim 1, wherein the support shed has a modulus of 65,000 to 130,000 psi as determined by a standard ASTM test, and a hardness in the range of 60 to 80 Shore D.

7. The insole of claim 1, wherein the support shell has a thickness of 2 mm.

8. The insole of claim 1, wherein the midfoot portion has a raised longitudinal arch on the medial side configured and shaped to support an arch of the user.

9. The insole of claim 8, wherein the midfoot arch portion is integrally formed within the midsole portion of the insole.

10. The insole of claim 1, wherein the support shell extends laterally along the insole bottom surface at the midfoot arch portion and the forefoot MTB-1 joint portion.

11. The insole of claim 1, wherein the foam body has a hardness in the range of 30 to 80 on the Asker C scale.