WO2018013802A1

WO2018013802A1 - Dynamic therapeutic insole and system for selective offloading of plantar abnormalities

Info

Publication number: WO2018013802A1
Application number: PCT/US2017/041920
Authority: WO
Inventors: Craig VERDIN; Nilin RAO; Ellen GLICKMAN
Original assignee: Therapod Medical Llc
Priority date: 2016-07-13
Filing date: 2017-07-13
Publication date: 2018-01-18

Abstract

The invention provides an insole assembly which is a sole shaped member having removable plugs at specific pressure points and which are concentric circles in the sole shaped member. In addition, the plugs are color coded to provide for a system of treatment which can easily be adjusted to provide support in the event of a change to the size of a lesion being treated.

Description

DYNAMIC THERAPEUTIC INSOLE AND SYSTEM FOR SELECTIVE OFFLOADING

OF PLANTAR ABNORMALITIES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority under 35 USC §120 to United States Provisional Patent Application Serial Nos. 62/493,708 filed July 13,2016.

FIELD OF THE INVENTION

[0002] A dynamic therapeutic insole or insole member is provided which can be easily tailored to the needs of podiatric patients to permit off-loading for the prevention and treatment of plantar pressure disorders. In addition, the insole can be used as part of a system for progressive treatment of offloading of plantar abnormalities as the abnormality heals. The invention is specifically useful for diabetic patients.

BACKGROUND OF THE INVENTION

[0003] Current estimates indicate that chronic wounds account for almost 4% of total health care expenditures at a cost of $25 billion and, with a sharp rise in health care costs, exponential growth in the aging population, and recent spike in obesity/diabetic patients (Diabetic population's.1 million), the burden that wound care presents will continue to impact patients and society. The aim of this invention is to provide a cost-effective means of facilitating the healing process in chronic wounds by utilizing the principle of wound offloading (which refers to the practice of reducing compression directly to a wound area, either by staying off of it, or by diverting the pressure away from the wound). Friction on the plantar aspect of the foot is know to be the driving factor in the formation of many plantar abnormalities, especially in diabetic populations; therefore, the principle of offloading is seen as a preventative measure to reduce friction in addition to dispersing normal pressure points that can be found on the plantar aspect of the foot in an effort to encourage healing of afflicted areas. The value of this invention is that it encourages better outcomes for patients by empowering patients with the ability to become more proactive in the healing process and contribute to the efforts of podiatrists and wound care experts.

[0004] There are numerous products in the podiatric marketplaces that aim to prevent the formation of plantar abnormalities that arise arise due to foot type, abrasion, sheer forces, gait pattern, and/or bony abnormalities; however, there are few products that address the plantar abnormalities once they have formed. Many of these prevention products take advantage of the principle of offloading in an effort to reduce the amount of pressure and abrasion in the afflicted areas, !n each step an average human takes, the foot will be tasked with supporting a force that equates to 3 to 6 times one's body weight. As a result of the loading of the foot, abrasion is typically increased, which leads to irritation, inflammation, and even the destruction of the skin that may place the patient at a higher risk for adverse outcomes. Moreover, if the patient does not effectively offload the afflicted areas, he/she may be subjected to pain, infection due to destruction of tissue, among other adverse outcomes.

[0005] Offloading is seen as an effective means of providing relief and preventing adverse outcomes by effectively reducing pressure, abrasion, and shear forces. Many insoles on the market are geared towards distributing the pressure that may arise in hopes of potentially reducing the potential for abrasion but, due to the complexity of the human foot biomechanics, these variables are difficult to contain due to their dynamic nature. The problem with current foot care products is that they are solely designed to prevent plantar abnormalities from occurring but, once these abnormalities occur, these products are rendered useless and the focus of treatment changes.

[0006] With respect to the current products that do address plantar abnormalities that may arise due to foot type, abrasion, sheer forces, gait pattern, and/or bony abnormalities, none are designed to fit inside of a patient's own shoe, decreasing the likelihood that a patient will use the product. Unfortunately, patient compliance is known to be a contributing factor to decreased healing and potential complications that may arise from whatever plantar abnormality is being treated. Thus, this provides a significant problem.

[0007] Existing practices for planar treatment can be time consuming and inefficient. The present invention provides a system of health care for use in wound care clinics and podiatrist offices where it can be used as a tool in the treatment of common pathologies that impact diabetics, runners, or anyone who experiences abnormalities on the plantar aspect of the foot due to abrasion, pressure, or underlying issues. The purpose of this invention is to reduce abrasion/pressure within the afflicted area which in turn, maximizes healing while providing the comfort of a traditional insole/orthotic. This approach can be contrasted by the prior art use of padding that is cumbersome and inconvenient. In addition, the present invention provides the patient with the ability to manipulate this product to their needs as they present, and over time during the healing process.

[0008] Another problem with the current measures for treating plantar abnormalities once they have arisen is the inability to effectively provide sufficient offloading over the duration of the healing process as the said pathology become smaller and eventually heals. Therefore, there is a need for a dynamic insole that has the ability to be modified for the proper offloading of afflicted areas of the human foot. Such a system should properly offload any kind of plantar abnormality, provide and accommodate for the healing process, and provide comfort without impacting the patient's daily activities in an effort to increase compliance and, therefore, lessen the risk for adverse outcomes.

[0009] The present invention provides a therapeutic insole or insole member that is used for the treatment of plantar lesions/ulcers/abnormalities which integrates standard treatment techniques into an insole. This product has the potential to impact the existing standard of care by providing the foot and ankle clinician with another tool and can also be utilized by the patient for treatment of more common plantar issues. The advantage of this product is that it is relatively easy to use, requires very little modification to maximize healing, and can be modified over time to allow a treatment modality that is dynamic and self -directed.

[0010] While this product was created with the diabetic patient in mind, due to the unique design of the insoleor insole member, it is a versatile product with widespread applications and can be used to treat any pathology (corns, blisters, callouses, warts, and potentially bunions) that can be found on the plantar aspect of the foot. Thus, the target population for the present invention is any group that might have a plantar pathology attributable to friction, plantar pressure, or that might benefit from offloading (meaning a re-distribution of pressure away from a defined higer risk area of the plantar surface).

SUMMARY OF THE INVENTION

[0011] In a first aspect, the present invention provides a shoe insole system with strategically placed concentric shaped inserts or plugs including specifically octagons, hexagons, ovals and circle/rings that are inscribed through the entire layer of a compressive material which forms all or part of the insole member. These plugs are located in areas where plantar pressure and abrasion is typical. By removing the plugs to match the circumferential border of the afflicted area, the patient can effectively reduce plantar pressure, abrasion, and shear forces that may be exerted on the skin or afflicted sites (i.e. , the lesion), leading to relief and an increased rate of healing. As the abnormality heals, concentric rings can be added back to the original site to add a circumferential layer of support that will eventually lead to a fully restored insole that the patient may use in the absence of pathology. In addition, the insole can be used inside of the patient's own shoe or it may supplement the use of other offloading products (inside of walking boots or chassis).

[0012] The present invention utilizes an off-loading convention or treatment regime using a sole and plug assembly that allows for normal use of the foot in question and in which use pressure is re-directed away from the ulceration. The invention relates to an insole or insole member that has removalbe plug assembly members that allow the wound to be "suspended" or subjected to less direct pressure than it otherwise would be during use, meaning that are under the ulceration includes a depression or void that may be covered with a material of lesser thickness than the area surrounding the depression. Moreover, the invention uses a configuration which has a round or roundish outline, and is preferably oval or circular (including rectilinear shapes with more than 4, and preferably 6 or more sides) to equalize the pressure distribution at the edge of the void left by a removed plug member. Further it is an advantage to provide the edge at an angle of from 45° to 120°, and preferably from 75° to 105° relative to the top surface of the insole so as to direct the patient's sole to an off-loading scheme which equalizes the re-distribution of the weight, pressure and friction about the wound. Advantageously, the void or the entire insole member can include a covering which redistributes the pressure over the void so as to cause "hammocking" or "trampolining" at the lesion-void interface.

[0Q13] The plug assembly members preferably include a central circle and at least one, and preferable two or three surrounding concentric rings that assemble to fill a series of decreasing diameter voids that are positioned corresponding to the usual placement of plantar ulcerations or wounds (eg. , at the heads of the first and fourth or more metatarsals, at the ball of the heel, and at the pads of the toes) relative to the remaining shape of the insole member Thus, the plug assembly can be totally removed to allow for the largest size wound, for example under the head of the first metatarsal, and as the wound heals, the rings can be re-inserted into the insole to account for a decreasing size wound over time. [0014] Additionally, the invention relates to the use of a color coding system to code the user to the proper treatment of any areas affected. For example, for each plug assembly, the rings can include a green outer ring, yellow inner ring, and a red center plug, and the user begins by removing the green ring and assembled yellow and red rings, and can reinsert the green ring into the sole member following a course of healing, for example, after one month, and after second month, can insert the yellow ring, and after a third month can insert the red central circle to reassemble the entire sole member. Of course, it is understood, that these colors are exemplary, and other color systems can be used where the center member is the same color and the surrounding inserts respectively have the same color and in which the inserts are of a contrasting color with the rest of the insole.

[0015] The present invention provides an insole system composed of a polymeric material which is biocompatible, durable, has the desired compression characteristics and can easily be shaped in the prescribed shape. One suitable material is ethylene-vinyl acetate (EVA), alone or in combination with outher suitable components or additives, such as a biocide or odor reducing agent or reinforcing filler, in addition to other supplemental materials. The insole can effectively treat any plantar abnormality that may benefit from the principle of offloading in an effort to reduce plantar pressure, abrasion, and shear forces. The goal of the insole and the system of treatment which utilizes it is to serve as an alternative to current treatment products or regimes for patients and clinicians who seek an intervention that complement their daily functions, therefore, increasing compliance and outcomes.

[0016] In addition, the proposed invention seeks to provide a cost-effective device and system for providing plantar foot care at a time when health care expenditures are at an all- time high, with the most significant portion of plantar abnormality expenditures caused by hospitalization as a result of complications or non-healing. By allowing the patient to have access to the present invention, patients are encouraged to be proactive in the healing process and, hopefully, reduce the potential for delays in resolution that might have a significant impact on expenditures and resources. In addition to reducing the rate of hospitalization or physician visits, the present invention aims to reduce the amount of time that clinicians spend nursing the abnormality, which will increase the rate of positive outcomes in patients. By reducing the amount of time patients spend in the office of physicians, this allows the physician to better utilize resources that will ultimately benefit the patient and increase the capability of the system to treat more patients. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present disclosure is best understood from the following detailed description when read with the accompanying Figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0018] Figure 1 is an exploded perspective view of the insole in accordance with the invention illustrating the progressive concentric circlular plugs situated so as to allow plantar off-loading at locations normally subject to problems;

[0019] Figure 2 is a top view of an insole in accordance with the invention illustrating additional plug assemblies and locations; ;

[0020] Figure 3 is a top view showing an insole in accordance with the invention with two plug assemblies wherein the rear plug assembly is under the ball of the heel and the more forward plug assembly is under the head of the first metatarsal;

[0021] Figure 4 is a top view showing an insole in accordance with the invention with two plug assemblies wherein the rear plug assembly is under the ball of the heel and the more forward plug assembly is under the head of the second metatarsal;

[0022] Figure 5 is a top view showing an insole in accordance with the invention with two plug assemblies wherein the rear plug assembly is under the ball of the heel and the more forward plug assembly is under the head of the third metatarsal;

[0023] Figure 6 is a top view showing an insole in accordance with the invention with two plug assemblies wherein the rear plug assembly is under the ball of the heel and the more forward plug assembly is under the head of the fourth metatarsal;

[0024] Figure 7 is a top view showing an insole in accordance with the invention with two plug assemblies wherein the rear plug assembly is under the ball of the heel and the more forward plug assembly is under the head of the fifth metatarsal;

[0025] Figure 8 is an exploded detail of the plug assembly of the present invention;

[0026] Figure 9 is an exploded bottom view of the insole of the present invention including the insole as a component of a shoe; [0027] Figure 10 is a top view of the invention showing the insole and plug assemblies and including plugs assemblies corresponding to the toes and also illustrating the system which utilizes a color coding to prescribe a treatment regime;

[0028] Figure 1 1 is afront view of the insole and plug assemblies of Figure 10;

[0029] Figure 12 is a back view of the insole and plug assemblies of Figure 10;

[0030] Figure 13 is a medial side view of the insole of Figure 10;

[0031] Figure 14 is a lateral side view of the insole of Figure 10;

[0032] Figure 15 is a top view of an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0033] The proposed invention comprises an insole assembly 100 and treatment system that seeks to utilize the principle of offloading to target any plantar abnormalities by reducing the plantar pressure, shear stress, and abrasion that may arise in the afflicted areas through means of strategically placed, pre-punctured concentric circles/rings through the entirety of the insole in the y-direction. The composition of the insole is a material which is suitable for wear, which is compressible, and which can be easily shaped. Elastomers or visco-elastomer, which are suitable include etheylene vinyl acetate (EVA), butyl rubber, natural rubber, choloroprene polyether polyurethane, as well as silicone elastomers are a few examples of sutiable materials. The material may include suitable additives, such as colorants, biological agents, such as fungicides, bactericides, UV agents and fillers, and suitable cross-linking agents as are necessary to produce an elastomeric material having a hardness of 10-80 on the Shore 00 scale, and an elongation to break of 150-350 in accordance with ASTM 412. As is shown in the side views, the insole may include a number of layers including a more rigid base and softer or more elastic (for example by 25% or more) coverings, including for example, a top coerving of Spancore that does not include the perforations and insert assmeblies, but overlay them.

[0034] In a first embodiment, the insole comprises a relatively co-planar form having a thickness of 0.1 to 1 .0 inch, and preferably from 0.25 to 0.75 inch and most preferably from 0.4 to 0.6 inch thick, and that has the outline of a shoe last (corresponding schematically to the outline of a foot), which has a rounded rearward heel area that extends into the medial arch area in which the medical side curves inwardly on the shape, and the lateral side curves outwardly toward the ball of the shape, which represents the widest portion of the shape and beyond that, the shape rounds forward in an egg-shape with the longest portion being the medial third of the shape, corresponding to the area under the first or second toes. In a further embodiment shown in Figure 15, the insole member has a front area that extends forward from the ball of the foot in a linear shape and is squared off the front edge of the foot to correspond to the shape of a walking cast.

[0035] Figures 2-7 show a top view of several variants of an insole assembly 102 that compromises a plurality of plug assemblies comprising concentric shapes, namely, circles 103 that extend through the entirety of the insole 104 and which comprise a center circle surrounded by one or two or more concentric rings. These concentric circles can be placed in the insole in afflicted areas that may be subjected to heightened plantar pressure, shear stress, and abrasion and may benefit from the principle of offloading. The plugs have exterior surfaces or edges 105 that form a right angle +/- 5°, and preferably +/-3°, and most preferably +/-2°. Thus, regardless of which of the circles has been removed, the void is left with a circular outline having a right angle edge which equalizes the distribution of pressure on the foot around the wound (as compared to shapes which include angles that could cause pressure points around the wound area).

[0036] In Figures 2-7, each insole variant is shown to have concentric circles placed under the all or one of the metatarsal heads 105 and the heel 106, area that typically experience heightened plantar pressure, shear stress, and abrasion. These are combined into a single insole in the embodiment shown in Figure 10. Figure 8 shows an exploded side view of the plug assembly 107 of the insole insolethat which preferably comprises interlocking concentric rings 108-110 and 110 and a center circle. The concentric rings fit inside of each other, can be removed to fit the circumference of the plantar abnormality, and come in variable sizes. In this variant, the functional unit is composed of three rings 108,109,110 and a circle 111. The largest ring 108 is 1 .5 +/- 0.25 inches in the x-direction and 0.5+/- 0.1 inches in the x-direction. The middlemost ring 109 is 1 .0 +/- 0.25 inch in the x-direction and 0.5 +/- 0.1 inches in the y-direction. The innermost ring 110 is 0.5 +/- 0.25 inches in the x- direction and 0.5 +/- 0.1 inches in the y-direction. The center plug member 111 is a circle without an internal void. .As the diameter of the underlying pathology is reduced, the concentric rings can be added back to their place of origin to provide continuous offloading that matches the circumference of the healing plantar pathology. After the plantar abnormality has healed, the patient will have a fully functional insole that can be used even in the absence of pathology with all rings placed in their place of origin in the void formed by there removal 102.

[0037] Given the high recurrence rate of many plantar abnormalities, the proposed invention seeks to eliminate the potential for waste of resources by providing a dynamic option that matches the rate of healing. Figure 9 shows an exploded side view of the insole as it would appear inside of the patient's own shoe 111. The advantage of the present invention is that is can be placed inside of the patient's shoe or in a further embodiment can be modified to match existing offloading devices such as post surgical shoes or a removable surgical walker.

[0038] Additionally, the present invention relates to a system of treatment in which a patient is directed by a health care professional to acquire the insole and to remove the insert assembly to a certain color. In accordance with this facet of the invention, the inserts of the plug assembly are color coded, for example, in green for the largest, yellow, for the second, and red for the most intense area of ulceration. This aspect of the invention is illustrated in Figure 10. In this embodiment of the invention, the insole 201 is illustrated as having an orthotic contour with a medial arch support 202 on the top side and lateral 210 and medial sides 212 and heel cup 214 that cradle the plantar surface. In this embodiment, the plug assemblies can be removed through the bottom of the insole, while the top surface of the insole is covered by an elastomeric layer, such as for example, the neoprene material sold under the tradename SpenCore by Spenco. Thus, when the plug member of the assembly is removed, the void remains in the area underlaying the top covering, and the surface covering softens the pressure distribution at the edge of the insole suring use with the insert removed.

[0039] As to the method of therapy,for example, in the case of a heel abrasion, the user may be instructed to remove the largest circle or the green circle for a week, and then to reinsert the yellow circle after two weeks and then to re-insert the red circle. Thus, the health care provider can provide a dynamic treatment regime to suit the dynamic situation of the patient as they heal and based on the color of the insert which can be assigned to a length of off-loading therapy for a corresponding size using the insole. [0040] In the further embodiment shown in Figure 14, an insole 301 is illustrated having a first set of interlocking inserts 303 which comprise for example a first row of hexagons 304, a second row of hexagons, 305, and a third row of hexagons, 306, which begin distally under the tow area and extend proximally to the medial arch area of the foot, approximately ½ of the way along the Ingth of the foor. The concentric shapes may mimic the shapes of the larger inserts, such as hexagons, or octagons. These inserts fit together to complete the insole, but can be separately removed or removed as a partial assembly.

[0041] Further in this embodiment, the insert assembliy includes the concentric ring/circle, 308 previously mentioned, but illustrate as having a larger ring 312, and a center circle plug or insert 314. The heel cup area also includes the concentric ring plug assembly 308, but here with an outer ring, 310, an inner ring 312, and an inner circle 314 of the dimensions previously mentioned for the version shown in Figure 10.

[0042] The foregoing has outlined features of several embodiments so that those skilled in the art may better understand the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.

Claims

WHAT IS CLAIMED IS:

1 . An insole system comprising a sole member having one or more plug assemblies, wherein the sole member has an outline which has a rear rounded heal portion that flares on a lateral side to a wider area and which curves inwardly on a medial arch side and then widens at a ball area and terminates in a toe area and which comprises an elastomer which is a biocompatible material and having a hardness of 30-80 on the Shore 00 scale, and which has a thickness of from 0.3 to 1 .5 inch between a top layer and a bottom layer and which has a recess forming a void therebetween which houses a plug assembly having a shape and size to complete the void of the recess, the recess having an edge surface between the top layer and the bottom layer which form a 90° angle =/-5° with the top surface of the sole member, and the plug assembly comprising a first shape having a diameter of from 0.4 to 0.8 inch and a concentric shape having an outer diameter of from 0.8 to 1 .5 inch, and the recess formed in the sole member at a place that corresponds to a placement of the ball of a heel or the a head of a metatarsal on the insole during use of the insole system.

2. The insole system of claim 1 , wherein the sole member is comprised of a material comprising one or more of EVA, a silicone elastomer, and a thermoset polyether polyurethane.

3. The insole system of claim 2, wherein the material further comprises a biocidal agent.

4. The insole system of claim 3, wherein the sole further comprises a top layer which overlays the sole including the recess.

5. The insole system of claim 1 , wherein the sole member has a recess formed in the sole member at a place that corresponds to a placement of the ball of a heel and to the a head of a metatarsal on the insole during use of the insole system.

6. The insole system of claim 1 , wherein the sole member has a second recess formed in the sole member at a place that corresponds to the placement of a toe during use and the second recess includes a second plug member.

7. An insole having an outline which corresponds to the shape of a sole of the foot and has a thickness of from 0.3 to 1.5 inch and which has a recess therethrough which houses an assembly of inserts of the same thickness so as to complete the recess and which comprise a circle or rectilinear shape having at leat 6 sides, and at least one concentric inner ring and one concentric outer ring with the outer ring having a diameter in the x- direction of 1.5 inch +/-0.25 inch, the inner ing having a diameter in the x-direction of 1 inch +/-0.25 inch,, and the circle having a diameter of in the x-direction 0.5 +/-0.25 inch.

8. An insole of claim 7, which comprises EVA,

9. An insole of claim 7, wherein the circle has a top surface which is red,

10. An insole of claim 8, wherein the inner ring has a top surface which is yellow.

1 1 . An insole of claim 8, wherein the outer ring has a top surface which is green.

12. An insole of claim 8, wherein the sole member is blue.

13. An insole of claim 8, wherein the recess has a placement corresponding to the placement of the bail of the heel, or the head of a metatarsal or a toe during use.

14. An insole of claim 1 , wherein the insole further includes an insert assembly that includes a row of at least two adjacent hexagons that include the plug assembly.

15. An insole of claim 1 , further including a surface covering comprising neoprene and overlaying an area over a recess.

16. A method of treatment of a foot of a user having a condition which includes one or more of an ulcer, pre-ulcerative lesion, a caliousity, a corn or a blister comprising the steps of:

providing an compressive insole having an outline which corresponds to the shape of a sole of the foot and has a thickness of from 0.3 to 1 .5 inch and a top surface of a first color and which has a recess therethrough which houses an assembly of inserts of the same thickness so as to complete the recess and which assembly comprise a circle having a top surface of a second color and at least one concentric inner ring having a top surface of a third color and one concentric outer ring having a top surface of a third color with the outer ring having a diameter in the x-direction of 1.5 inch +/-0.25 inch, the inner ring having a diameter in the x-direction of 1 inch +/-0.25 inch,, and the circle having a diameter of in the x-direction 0.5 +/-0.25 inch,

evaluating the condition of the user;

removing or directing the user to remove one or more of the inserts comprising circle, the inner ring or the outer ring.

17. A method of treatment of a foot of a user as set forth in claim 16, wherein the user is directed to remove the insert by choice of color of the insert.

18. A method of treatment of a foot of a user as set forth in claim 17, wherein the user is directed to re-insert the insert by color.

19. An offloading plantar cushion with concentric adjacent circular punctures containing a complimentary insert assembly having an outer ring, and an inner circle, the outer ring having a diameter of 0.75-1 .25 inch, and the inner circle having a diameter of 0.25-0.75 inch.

20. An offloading plantar cushion as set forth in claim 19, further including at least one hexagonal puncture having a complimentary insert assembly that further includes a hexagonal insert containing the insert assembly having the outer ring and the inner circle.