RELATED PATENT APPLICATION:

This application claims the priority to and benefit of Indian Patent Application No. 202141035407 filed on August 05, 2021; the disclosure of which are incorporated herein by reference.

FIELD OF THE INVENTION:

The present invention relates to a shoe insole to heal foot ulcers and generally relates to the field of material engineering for biomedical application or biomechanics. More specifically, the present invention relates a shoe insole to heal Diabetic Foot Ulcers (DFUs) and method of manufacture thereof.

BACKGROUND OF THE INVENTION:

According to the research, patients with diabetes are prone to have major foot problems. This is because the foot expresses many of the underlying effects of diabetes, including neuropathy, vascular disease, and diminished response to infection. As a result of the neuropathy, the foot can develop an ulcer. This happens for two reasons. The first is that the neuropathy causes paralysis of small muscles in the foot, which results in clawing of the toes. Clawing of the toes causes prominence of the metatarsal heads (bones closest to the toe) on the bottom of the foot as well as the knuckles on the dorsum (top) of the foot. Diabetic foot ulcer (DFU) is a common and debilitating complication of diabetes. Often this is preventable by regular screening and addressing risk factors such as regular podiatry, good footwear, and early consultation with health care professionals.

Diabetic Foot Ulcers (DFUs) can lead to high-level amputation to 30%. Foot ulcers cause substantial morbidity, impair quality of life, engender the high treatment costs. Further, the treatment provided for foot ulcers is often inadequate, resulting in avoidable complications and unnecessary extended healing times.

The cause of diabetic foot problems and faulty wound healing in diabetes can be attributed to peripheral neuropathy, peripheral vascular (arterial) disease and tissue hypoxia, and abnormal cellular inflammatory pathways. The classic pathological triad that leads to amputation of these ulcers will include the stages of - losing sensibility in the foot, deformity of the joint and the trauma. These ulcers can be categorized as Neuropathic, Purely Ischemic, and Neuroischemic. This will result into the dead sensation and dryness of the skin over a period of time to the infected patient. This is called as Ischemic theory. The injury needs to be healed and to be repaired naturally by methods such as creating the pressure-off clutches using any special footwear. The flat foot creates more pressure points in fore foot (near the ball of the great Toe) and further leads to trauma.

Thus, ulcers are caused mainly by venous hypertension, partly by arterial disease or sometimes by the combination of both. Increased pressure of the cases of flat foot increases in capillary beds that the veins are draining. Capillaries consist of thin walls with single layer of cells with basement membrane [Armstrong, D. G., Short, B., Espensen, E. H., Abu-Rumman, P. L., Nixon, B. P., & Boulton, A. J. (2002). Technique for fabrication of an “instant total-contact cast” for treatment of neuropathic diabetic foot ulcers. Journal of the American Podiatric Medical Association, 92(7), 405-408]. Increased pressure causes the cells of these walls to separate, and plasma components will escape into the tissues. Thus, cellular function will be damaged in the surrounding tissues in presence of a minor trauma, leading to an ulcer.

Repetitive pressure and shear forces applied during walking make the ulcer more vulnerable. Hence, managing this ulcer effectively by preventing the damage leading to amputation is the goal. 85% of these ulcerations are preceded by ulcers and as per the survey; these ulcers are 30 times more likely to require an amputation. These ulcers are more likely to reform around (28 to 83%) within a year if not properly treated. Fig. 1A shows the Risk Factors for DFUs and their deformation. [Frykberg, R. G., Zgonis, T., Armstrong, D. G., Driver, V. R., Giurini, J. M., Kravitz, S. R., ... & Vanore, J. V. (2006). Diabetic foot disorders: a clinical practice guideline (2006 revision). The journal of foot and ankle surgery, 45(5), S1-S66].

Foot ulcers are also inflammations on the foot that are painful, irritating and cause much of the distress to diabetic patients. These sores will start as a red patch but develop into an infected wound within no time. It should be kept clean and applying bandages is necessary. Fig. IB shows various types of DFUs. DFUs are majorly formed by two common mechanisms by which foot deformity and neuropathy may induce skin breakdown in persons with diabetes. Multiple pathologies may be implicated, from vascular disease to neuropathy to mechanical trauma. Fig. 1C represents a schematic summary of all the reasons and/factors of DFUs formation. Often foot needs to be free of weight and pressing. There are a few therapies recommended to heal these ulcers. Medical therapy and management of these ulcers is to do with infection control, ulcer debridement, off-loading, and revascularization.

Foot ulceration is the precursor to non-traumatic lower extremity amputations in approximately 85% of cases [Frykberg, et al 2006]. Prevention and cure of DFUs starts with diagnosing and screening for loss of protective sensation. Specialist clinics may quantify neuropathy with biothesiometry, measure plantar foot pressure, and assess lower extremity vascular status with Doppler ultrasound and ankle-brachial blood pressure indices [Singh, N., Armstrong, D. G., & Lipsky, B. A. (2005). Preventing foot ulcers in patients with diabetes. Jama, 293(2), 217-228]. The footwear usage for prevention of ulcers is a preliminary but an effective treatment methodology adopted widely for obstructing the growth of the DFUs in the early stages. However, the value of various types of prescription footwear for ulcer prevention is an unexplored area.

DFU have been treated by wide variety of methods by clinical experts, Podiatrists as part of the neuropathy treatments and nursing management techniques & practices. Seniors in long-term care often suffer from these types of chronic wounds, and they’re at serious risk of infection. Most critically, ulcers can cause significant distress in a patient, at a time when social distancing and COVID-19 have already complicated the care. Majority of the methods include Heeling Pads, Compression Wraps, Paddings, Orthoses, Half Shoes, Pneumatic Walkers, and Total Contact Casts (TCCs).

Majority treatment for diabetic ulcers is of the following types-

1. Diabetic footwear

2. Specific medicines for oral intake

3. Honey Topical therapy

4. Other unconventional methods Diabetic Footwear:

One of the prior implementations of healing of these ulcers are the diabetic footpads as part of the healing technique known as - The “Total Contact Cast” (TCC). The total contact cast is a specific casting technique that is used to heal Diabetic Foot Ulcers and to protect the foot during the early vulnerable phases of Charcot fracture dislocations [Armstrong, D. G., Short, B., Espensen, E. H., Abu-Rumman, P. L., Nixon, B. P.,& Boulton, A. J. (2002). Technique for fabrication of an “instant total - contact cast” for treatment of neuropathic diabetic foot ulcers. Journal of the American Podiatric Medical Association, 92(7), 405-408]. The cast is used to heal Diabetic Foot Ulcers by distributing weight along the entire plantar aspect (sole) of the foot. It is applied in such a way to intimately contact the exact contour of the foot; hence the name, "Total Contact Cast". The cast relieves the pressure on the prominent areas of the foot, permitting the ulcers to heal. The cast should apply in such a way that the patient can remain mobile during the treatment of the ulcer. The cast is moulded to the contours of the foot from the back of the heel through the arch region, in the region of the metatarsals, around the metatarsals, and even to the toes. The pressure, which has been concentrated on the bony prominence, is now distributed over the entire sole of the foot. Fig. ID shows the Pressure distribution under Total Contact Cast.

Layered compression therapy for venous leg ulcers and ulcers associated with chronic leg edema has been shown to be an effective treatment in patients with adequate arterial circulation. Present day treatment methods include the shoes designed for people with diabetes Casts are - foot braces, compression wraps, and shoe inserts to prevent corns and calluses. Layered compression therapy was an effective and safe treatment in this diabetic population with adequate arterial circulation. Reduced compression also can be helpful in some patients with arterial compromise [Bowering CK. Use of layered compression bandages in diabetic patients. Experience in patients with lower leg ulceration, peripheral edema, and features of venous and arterial disease. Adv Wound Care. 1998 May- Jun;ll(3):129-35. PMID: 9729944]. Fig. IE shows various healing treatment footwear available as customized designs of TCC.

Robert G. Frykberg et al. listed all the DFU's formation process, risk factors and types. The clinical guide given by these group has an extensive list of DFU's treatment methods [https://3dprint.com/269378/rokit-healthcare-reveals-worlds- first-all-in-one-bioprinting-platform-with-built-in-bioreact or-chamber-plasma- sterilizer-and-6-rotary-printheads-dr-invivo-4d6/]. TCCs are considered by many specialists to be the gold-standard offloading modality. TCCs employ a well moulded, minimally padded cast that maintains contact with the entire plantar aspect of the foot and the lower leg [ Armstrong, D. G., Short, B., Espensen, E. H., Abu-Rumman, P. L., Nixon, B. P., & Boulton, A. J. (2002). Technique for fabrication of an “instant total-contact cast” for treatment of neuropathic diabetic foot ulcers. Journal of the American Podiatric Medical Association, 92(7), 405- 408]. Total contact casting and removable cast walkers appear to be clinically effective. One systematic review of randomized controlled trials found that healing rates for patients who were treated by total contact casting was between 74% and 95%, and for removable cast walkers was 52% and 85% [Majid, U., & Argdez, C. (2020). Off-Loading Devices for People with Diabetic Neuropathic Foot Ulcers: A Rapid Qualitative Review].

Yun Gao et al. [Gao, Y., Wang, C., Chen, D., Huang, H., Chen, L., Liu, G. & Ran, X. (2021). Effects of novel diabetic therapeutic footwear on preventing ulcer recurrence in patients with a history of diabetic foot ulceration: study protocol for an open-label, randomized, controlled trial. Trials, 22(1), 1-11], optimally designed therapeutic footwear consisted of merino wool, vibration chip, and orthopaedic insoles is designed to influence multifaceted mechanisms of foot ulcer occurrence. Fig. IF shows the shoes optimally designed therapeutic footwear by Yun Gao et al. They claimed at least a 30% reduction in the incidence of ulcer recurrence from baseline to the end of intervention.

Special drugs/ medicine: There are a few drugs to improve the oxygen Circulation for the blood cells in the foot, but their result is limited.

Honey Topical Therapy: Tropical honey has exclusive anti-bacterial properties with improved healing ability.

Neuropathic Ulcers resulting from Ischemia and improved infection are the majority of the Diabetic Foot Ulcers (DFU). Fig. 1G illustrates the various ways leading to amputation with the deformation of the wounds related to DFUs. jUlbrecht, J. S., Cavanagh, P. R., & Caputo, G. M. (2004). Foot problems in diabetes: an overview. Clinical infectious diseases, 39(Supplement_2), S73-S82]. For diabetic footwear to be most effective, it must be worn at least 60% of the time. All reported rates of compliance fall well short of this level. The style and appearance of the shoe have been commonly blamed for this poor compliance [Daniel J. Macfarlane, Jeffrey L. Jensen; Factors in Diabetic Footwear Compliance. J Am Podiatr Med Assoc 1 November 2003; 93 (6): 485-491. doi: https://doi.org/10.7547/87507315-93-6-485].

Infection of a foot ulcer can be prevented with the below existing methods- Padding, Orthoses, Half Shoe, Pneumatic Walkers, Total Contact Casts, foot baths, disinfecting the skin around an ulcer, keeping the ulcer dry with frequent dressing changes, enzyme treatments, and dressings containing calcium alginates to inhibit bacterial growth.

The major drawbacks of the presently available product or products include: a) No footwear invention till date for the improvement of Oxygen circulation:

The modern therapeutic footwear has a complex, layered, structure including an outer sole, midsole and insole [Chatzistergos, Panagiotis E.; Gatt, Alfred; Formosa, Cynthia; Farrugia, Kurt; Chockalingam, Nachiappan (2020). Optimised cushioning in diabetic footwear can significantly enhance their capacity to reduce plantar pressure. Gait & Posture, 79(), 244-250. doi:10.1016/j.gaitpost.2020.05.009]. The existing methods only give a subjective solution to the Diabetic Foot Ulcers and are not aiming at healing the deformity with improved supply of oxygen. The deformities formed as wounds are mainly due to higher plantar pressure in the so-called flat foot. The sensations in the foot gradually disappear due to the reduced oxygen circulation which is a food for cells to synthesize haemoglobin. b) Difficulty in Wearability:

Existing therapies of TCC and other diabetic foot bandages cover the entire foot whose removal and re-winding to the foot is time taking. c) Existing Treatments are costly:

At present the foot ulcers treatment is costly. Some available products are difficult to handle and they require the internet facility. Some can’t take care properly and on the regular basis. The mean cost of wound care over 12 months was an estimated £7800 (Rs. 68,000) per DFU (of which 13% was attributable to amputations), ranging from £2140 to £8800 (around Rs. 75,000) per healed and unhealed DFU, respectively, and £16,900 (Rs. 1,55,000) per amputated wound. d) Compression wraps:

Compression is applied to the leg to minimize edema or swelling. This can be achieved by wearing compression stockings, multi-layer compression wraps, or wrapping an ACE bandage or dressing from the foot to just below the knee [How to apply an effective multilayer compression Bandaging, An article by Alison Hopkins, a Clinical Nurse Specialist, East London Wound Healing Centre, Tower Hamlets Primary Care Trust www.woundsinternational.com/uploads/resources/content_9366.p df]. The type of compression that will be applied will depend on the ulcer’s characteristics and amount of drainage. After ulcer closure, compression stockings may help to control the venous insufficiency.

Thus, the inventors of the present invention come up with the solution to overcome the above existing drawbacks. Here in the present invention, one novel therapy for revascularization aided by a technological sole consisting of a layered pad kind of assembly for the footwear is disclosed. The Shoe insole (BioCure InSole) of the present invention consists of layers of different soles that help in reducing the inflammation of the foot ulcers. This technique improves the vasculogenic circulation of oxygen which is the main cause for the impairment of the foot tissues. Circulation of improved percentage of oxygen over the foot surely heals the early forming of the ulcer and prevents the further inflammation. The use of diabetic footwear has been shown to be effective in reducing the incidence of diabetic foot ulcerations. The proposed Shoe insole (BioCure InSole) can be worn during the leisure time at home with ease as a regular footwear. Further, the said shoe insole of the present invention is economically manufactured and made available to common public in relatively low economic cost.

OBJECTS OF THE INVENTION:

The primary objective of the present invention is to provide a shoe insole to heal Diabetic Foot Ulcers (DFUs).

Another objective of the invention is to design and provide shoe insole which helps in healing the DFUs by selective supply of oxygen produced from bamboo. Yet another objective of the invention is to provide a shoe insole where all the materials used in the respective layers are eco-friendly, and the shoe insole is made of biodegradable materials.

Another objective of the invention is to provide a shoe insole which can be economically manufactured and made available to common public in relatively low price; thus provide a cost-effective solution to DFU management.

Another objective of the present invention is to provide a shoe insole device design which is sustainable in nature and self-generating device that does not require any external power such as battery.

Another objective of the present invention is to provide the method of treatment of the DFUs using the shoe insole and shoe manufactured using shole insole of present invention.

Another objective of the present invention is to provide the method of manufacturing of the shoe insole and shoe product using the shoe insole.

Yet another objective of the present invention to provide a footwear product using novel shoe insole of present invention to heal Diabetic Foot Ulcers (DFUs).

Yet, a further objective of the present invention to provide a shoe insole for other disease application such as can be used in leprosy patients to treat their foot.

SUMMARY OF THE INVENTION:

Accordingly, the present invention provides a shoe insole to heal foot ulcers including Diabetic Foot Ulcers (DFUs). The shoe insole of the present invention helps in healing the foot ulcers including DFUs by selective supply of oxygen produced from bamboo, all the materials used in the respective layers are eco- friendly, and the shoe insole is made of biodegradable materials. The shoe insole of the present invention can be economically manufactured and made available to common public in relatively low price. The design is sustainable in nature and selfgenerating device and hence does not require any external power such as battery. The present shoe insole can be used for other disease application such as can be used in leprosy patients to treat their foot. In one aspect, the invention provides a shoe insole (10) to heal foot ulcers including Diabetic Foot Ulcers (DFUs) comprising: a first layer (1) of poly dimethyl siloxane (PDMS); a second layer (2) of bamboo; a third layer (3) of coconut coir, and optionally, an additional layer (4) of foam; wherein the first layer (1) of PDMS comprises a selective laser machined areas that face with the ulcer area (U) and provide a passage channel (C) for supply of oxygen; wherein the second layer (2) of bamboo provides and supply oxygen to the ulcer area (U) through the passage channel (C); and wherein the third layer (3) of coconut coir provides structural support, stability, and firmness to the sole.

The above said shoe insole (10), wherein the insole (10) facilitates oxygen supply to foot ulcer area (U) and increases oxygen in ulcer area (U) and blood which helps to reduce swelling, control of infection, and stimulate growth of new blood vessels.

The above said shoe insole (10), wherein due to laser machining of the sole it releases the oxygen to the ulcerated area (U), wherein the carbon dioxide is taken by the second layer (2) of bamboo, and the second layer (2) of bamboo releases oxygen which passes to ulcerated area (U) via the passage channel (C).

The above said shoe insole (10), wherein the layers (1, 2, 3) are formed using the biodegradable and natural eco-friendly materials and no chemical are added, and wherein the design of the shoe insole (10) is sustainable in nature and selfgenerating device that does not require any external power like battery.

The above said shoe insole (10), wherein the said shoe insole (10) provides optimum cushioning leading to improved pressure relieving capability of the footwear and wherein said shoe insole (10) is an easy wear and removable insole and can be worn at home by the patient without anyone’s aid.

The above said shoe insole (10), wherein the said shoe insole (10) is an insole cum treatment to patients which prevents progressive stiffening of collagen containing tissue and stops further thickening of the skin and loss of joint mobility. The above said shoe insole (10), wherein the bamboo in second layer also provides strength to the insole for more durability of the shoe insole.

In another aspect the invention provides a method of manufacturing of a shoe insole (10) and footwear product manufactured using the said shoe insole (10) as described above, wherein the method comprises the steps of:

Step 1: Storaging the raw material;

Step 2: Modelling the insole;

Step 3: Cutting the raw material;

Step 4: Sewing the cut-outs;

Step 5: Finishing is applied to the sewed product; and

Step 6: Packing the finished product.

In another aspect the invention provides a method for healing the Diabetic Foot Ulcers (DFUs) using a shoe insole (10) and footwear product manufactured therefrom, wherein the method of healing of DFUs comprises:

(a) providing a shoe comprising a shoe insole (10) to an individual having foot ulcer or DFUs;

(b) wearing the shoe comprising the shoe insole (10);

(c) facilitating oxygen supply to the ulcerated area (U) of the individual’s foot (F) by the shoe insole (10) of the shoe;

(d) increasing oxygen in cells and blood by supplying oxygen through the passage channel (C) of the shoe insole (10) to the ulcerated area (U) wherein the carbon dioxide is taken by the bamboo layer of insole (10) and the bamboo layer releases oxygen which is taken up by cells in the ulcer area (U), and thus increasing oxygen level in the ulcer area and blood;

(e) reducing swelling, controlling infection, and stimulating growth of new cells and blood vessels; and

(f) healing and recovery of foot ulcer (U) and/or DFUs of the shoe wearer.

In another aspect the invention provides a footwear product for wearing having ability to naturally heal the foot ulcers, wherein the footwear product comprises:

(a) a shoe covering - which covers the foot (F) of the wearer and keep the shoe remain attached with the foot of wearer; and (b) a shoe insole (10) attached below the shoe covenng - which acts as a base, provide support, protect foot (F), and naturally helps in healing the foot ulcer (U) of the wearer, wherein said shoe insole (10) comprises: a first layer (1) of poly dimethyl siloxane (PDMS); a second layer (2) of bamboo; a third layer (3) of coconut coir, and optionally, an additional layer (4) of foam; wherein the first layer (1) of PDMS comprises a selective laser machined areas that face with the ulcer area (U) and provide a passage channel (C) for supply of oxygen; wherein the second layer (2) of bamboo provides and supply oxygen to the ulcer area (U) through the passage channel (C); and wherein the third layer (3) of coconut coir provides structural support, stability, and firmness to the insole.

The shoe insole described above, the number of passage channels may be provided and distributed throughout the shoe insole or may be selectively designed and provided at places corresponding to specific ulcerated area (U) of foot.

The above description merely is an outline of the technical solution of the present disclosure; in order to know the technical means of the present disclosure more clearly so that implementation may be carried out according to contents of the specification, and in order to make the above and other objectives, characteristics and advantages of the present disclosure clearer, and easy to understand, specific embodiments of the present invention will be described in detail below.

BRIEF DESCRIPTION OF THE DRAWING(S):

Figure 1A: shows Risk Factors for DFUs and their deformation (Prior Art);

Figure IB: shows various types of Diabetic Foot Ulcers (Prior Art);

Figure 1C: shows Summary of Causes of DFUs (Prior Art);

Figure ID: shows Pressure distribution under Total Contact Cast (Prior Art);

Figure IE: shows various Healing Treatment Footwear available as customized designs of TCC (Prior Art);

Figure IF: shows the shoes optimally designed therapeutic footwear (Prior Art); Figure 1G: shows Pathways to Amputation (Prior Art); Figure 2: shows the three layers of shoe insole (10) of the present invention;

Figure 3: shows the flowchart for analysing, designing, simulating, fabricating, and testing of the prototype of the shoe insole of the present invention;

Figure 4: shows the flowchart for manufacturing or fabricating the shoe insole of the present invention.

Figure 5: Prototype/representative image of a footwear product using shoe insole (BioCure InSole)

DETAILED DESCRIPTION OF THE INVENTION:

Accordingly, the present invention provides a shoe insole (10) to heal foot ulcers including Diabetic Foot Ulcers (DFUs). The invention discloses and provides a novel shoe insole (BioCure InSole) wherein the layers used in the shoe insole happen to be a unique combination with the help of which the oxygen availability to the DFUs will improve and can serve as an effective vascular treatment and ulcer healing. The shoe insole (10) of the present invention can be made as a footwear and can be commercially manufactured. The shoe insole (10) is made of biodegradable materials and only natural eco-friendly products are used. The insole (10) cures the ulcer by effective oxygen supply and the invention will serve as a novel, sustainable solution that helps in early prevention of the diabetic ulcers and their growth.

DFU are treated with various kinds of footwear. Footwear and Orthotics plays an important part in treatment for DFUs. It greatly prevents their early formation. Offloading is to be done by allowing enhanced blood flow to the foot during healing. Improper footwear can worsen the condition of DFUs and hence it is essential for diabetic patients to wear the most comfortable shoes with that it is also essential to have proper oxygen supply. Studies have also shown that stiff soles may help with pressure offloading. Research has also demonstrated the effectiveness of custom footwear to offload pressure from the foot, particularly on the heel. DFU need a special footwear prescribed by a physician. Because diabetic footwear is effective in reducing plantar foot pressures, the present invention’s Shoe insole (BioCure InSole) (10) can serve as an important tool in the prevention of early stage DFUs. DFU need a special footwear prescribed by a physician. Prescription in footwear includes:

Healing shoes: Immediately following the surgery or as part of treatment of an ulcer, some type of shoe may be necessary before a regular shoe can be worn. These include custom sandals (open toe), heat-moldable healing shoes (closed toe), and post-operative shoes.

In-depth shoes: The in-depth shoe is the basis for most footwear prescriptions. It is generally an oxford-type or athletic shoe with an additional 1/4- to 1/2-inch of depth throughout the shoe, allowing extra volume to accommodate any needed inserts or orthoses, as well as deformities commonly associated with a diabetic foot. In-depth shoes also tend to be light in weight, have shock-absorbing soles, and come in a wide range of shapes and sizes to accommodate virtually any foot.

External shoe modifications: This involves modifying the outside of the shoe in some way, such as modifying the shape of the sole or adding shock absorbing or stabilizing materials.

Orthoses (singular: orthosis) or inserts: An orthosis is a removable insole which provides pressure relief and shock absorption. Both off the shelf and custom-made orthoses or inserts are commonly prescribed for patients with diabetes, including a special total contact orthosis which is made from a user’s foot model and offer high level of comfort and pressure relief.

Custom-made shoes: When extremely severe deformities are present, a custom- made shoe can be constructed from a cast or model of the patient's foot. These cases are rare. With extensive modifications of in-depth shoes, even the most severe deformities can usually be accommodated.

There are also some guidelines prescribed by experts to reduce the risk of DFUs to stop further deterioration leading to amputation which includes foam sole needs to be present in shoe, with sufficient dorsal movement for clawed toes extra depth sole with 6mm insole is preferred and an insole can be of any thickness with any modifications and can be made rigid rolled or rockered. The present invention of the shoe insole follows all the above guidelines. In one aspect of the present invention, the present invention provides a shoe insole (10) for healing a DFU and other type of ulcers such as ulcers in leprosy patients. The shoe insole (10) of the present invention mainly consists of three layers as below:

Layer 1: First top layer which consists of poly dimethyl siloxane (PDMS) which has selective laser machined areas for supply of oxygen to the ulcerated area (U).

Layer 2: Second layer is made up of bamboo for supply of oxygen to the ulcerated area (U). By supplying oxygen and increasing oxygen in blood helps to reduce swelling, control of infection, and stimulate growth of new blood vessels.

Layer 3: Third layer is made up of coconut coir for providing structural support. Layer 4: Optionally, an additional layer (4) of foam may be provided.

Now referring to Figure 2 to Figure 5, the figures describe the various aspects and embodiments of the present invention as disclosed in detailed below:

Fig. 2 shows the basic embodiment of the present invention showing the novel shoe insole (10), which can be used in manufacture of footwear that can be used for ulcers including DFU treatment, healing, and management. In the figure, the shoe insole (10) used for healing the foot ulcer (U) in individual’s or patients’ foot (F) consists of three layers and provide a passage channel (C). The said three layers shown in figure are: a first layer of PDMS (1); a second layer of Bamboo (2); a third layer of coconut coir (3). The said shoe insole may also optionally comprise further additional layers such as a fourth layer i.e. a foam layer (4) (not shown in Fig. 2).

First layer made up of Poly dimethyl siloxane (PDMS):

First Layer (1) is formed by Poly Dimethyl Siloxane. Poly Dimethyl Siloxane (PDMS) also known as dimethylpolysiloxane or dimethicone, belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. PDMS is a weakly cross-linked polymers that have small elastic modulus with high ranges of deformability. Due to its cross-linked nature, they are decomposed by excessive heating rather than melting. Hence, there won’t be a danger of deformation of the layer.

As shown in the figure, the said first layer (1) faces the ulcer area (U) and provides a passage channel (C) for flow and/or supply of oxygen. Oxygen is formed in the lower layer of Bamboo which flows through the channel (C) to the wound/ ulcer area (U) as represented by arrow in Fig. 2. Further, the Poly Dimethyl Siloxane has selective laser machined areas for supply of oxygen. Multiple selective laser machined areas may be provided in the insole.

In one embodiment the passage channel (C) is selective laser machined areas that helps in supply of oxygen to the ulcerated area (U). Multiple number of passage channels (C) may be provided and distributed throughout the shoe insole or may be selectively designed and provided at places corresponding to specific ulcerated area (U) of foot.

Second layer made up of Bamboo:

The second layer (2) is formed by bamboo. Since, the anaerobic infections are the most common causes due to lack of oxygenation in the tissues, increased oxygen level helps to reduce the rate of the infection and helps it to heal faster. Bamboo Sole layer is a natural synthetic fibre material. The maximum compressive strength for Bamboo is around 40 N/mm ² The said compressive strength value is considerably high thus making it suitable to be used as a sole. Bamboo sole can contain biologically active peptides and polysaccharides. The combined effect of these macromolecules with polyphenols and other metabolites in bamboo cellulose leads to healing of multiple biological effects and acts as anti-free radical, antiaging, anti-fatigue, anti-bacteria, antivirus, and as a functional dietary supplement, and as a cosmetic ingredient.

Further, the bamboo is specifically used for increased supply of oxygen. By increasing oxygen in blood helps to reduce swelling, control of infection, and stimulate growth of new blood vessels. When the patient places the foot (F) on the shoe sole (10) because of laser machining of the sole (10) it releases the oxygen to the ulcerated area because the carbon dioxide is taken by the bamboo and release of oxygen takes place. Since bamboo takes carbon-di-oxide and releases the oxygen, more amount of oxygen is released, and which helps the ulcer to cure faster. Mainly the bamboo layer provides oxygen to the ulcer area (U) through the passage channel (C), but the bamboo layer may also give the strength to the defined insole (10) and makes it durable as well. Third layer made up of Coconut Coir:

The third layer (3) in the insole (10) is formed by the coconut coir. The coconut coir is the base of the shoe insole (10). First layer (1) of PDMS and second layer (2) of bamboo are mounted on the coconut coir layer (3). The primary purpose of the coconut coir is to provide a structural support to the first layer along with the second layer. The coconut coir further provides the damping capacity to the foot and relieves the pressure. The coconut coir also provides stability and firmness to the sole. The passage channel (C) is present in the first layer (1) and the second layer (2).

A shoe insole (10) to heal foot ulcers including Diabetic Foot Ulcers (DFUs) comprising: a first layer (1) of poly dimethyl siloxane (PDMS); a second layer (2) of bamboo; a third layer (3) of coconut coir, and optionally, an additional layer (4) of foam; wherein the first layer (1) of PDMS comprises a selective laser machined areas that face with the ulcer area (U) and provide a passage channel (C) for supply of oxygen; wherein the second layer (2) of bamboo provides and supply oxygen to the ulcer area (U) through the passage channel (C); and wherein the third layer (3) of coconut coir provides structural support, stability, and firmness to the sole.

In one embodiment of the present invention, the shoe insole (10) can comprise of an additional fourth layer (4). The fourth layer is formed using a foam or like materials and may form the outermost layer of the shoe insole. The layer (4) is added in the sole for more comfortability in wearing the insole.

This BioCure InSole of the present invention has optimum cushioning leading to improved pressure relieving capability of the footwear.

In another aspect of the present invention, the shoe insole (10) of the present invention is designed, simulated, fabricated, and also tested. A method for production of shoe insole (10) and footwear product using the insole (10) involving the methods as described in Fig. 3 and Fig. 4. Fig. 3 represents another embodiment, which shows the sequential steps which are followed for designing, simulating, fabricating, and testing of the prototype of the shoe insole (BioCure InSole) of the present invention.

The sequential steps start with the analysis of the conditions of DFU. Certain predetermined conditions are predefined. The present conditions of the DFU are matched with the predefined conditions. If the said condition for analysis is not fulfilled, surgery of the ulcer is suggested. If the condition of DFU matches with the predetermined condition or in other words if the condition is fulfilled, the case of the inspection is detected followed by the analysis of the wound. The main parameters in the analysis include shape of the wound, area of the wound and the depth of the wound. Based on the analysis of the wound, the photograph of the ulcers is taken.

Followed by the photography of the ulcer, the pressure and the pressure points of the foot are identified. Identifying the pressure points is one of the most important factor for treatment of the DFU as the increased pressure especially in the cases of flat foot increases in capillary beds that the veins are draining. Relieving the pressure from such points helps to accelerate the healing process. The above steps are mainly performed to analyse the intensity of the wound and other factors.

Once the analysis of the wound is completed, the next step comes for the selection of the footwear structure. In the selection process, the three layers of the design are selected. A fourth layer may also be considered. After the selection of the layers, the design of the product is simulated. Based upon the results and readings of the simulation, fabrication of the product is performed, and the product is dispatched for testing. The finalized shoe insole (10) may be then used in a show for making the finished footwear product.

In another aspect, the invention provides a method for manufacturing of the shoe insole (10) of the present invention. Fig. 4 shows describe the sequential steps that will be followed in the form of flowchart to manufacture or fabricate the shoe insole of the present invention.

The manufacturing or fabricating the shoe insole (10) comprises the steps as below: Step 1: Storaging the raw material Step 2: Modelling the insole Step 3: Cutting the raw material

Step 4: Sewing the cutouts

Step 5: Finishing applied to the sewed product

Step 6: Packing the finished product.

Step 1 - Storaging:

The process of manufacturing or fabrication starts with the storaging. The storaging includes storing of raw material like layers or sheets of PDMS, Bamboo, coconut coir and foam etc. as described above, the shoe insole is a customised product and depends upon the conditions of the DFU. For different individual different insole is provided. Thus, all the raw materials are stored in the storage and based upon the readings and results of the simulations the material is selected.

Step 2 - Modelling:

After the storaging, the second step includes modelling. As mentioned above the insole of the present invention can be made as a footwear, the modelling of the shoe insole is performed. The modelling step is performed basically for defining the structure of the shoe sole. In the modelling step, firstly the type of the insole is selected which includes different layer designs like 1 -layer, 2-layer or 3 -layer design and the layers are retrieved form the storage. The layers in the insole of the present invention can be varied and tested with different material combinations. The addition of a layer of foam can also be an addition for more comfort to the foot. The layer design of the insole is selected based on the user’s requirement. Further, measurements are taken according to the user foot size to cut the raw materials. Accordingly, the model of the insole (10) is finalized.

Step 3 - Cutting:

After finalizing the model of the insole according to the user’s requirement, the cutting step on the raw material is performed based on the measurements taken in the modelling step. The work pieces mainly include the poly dimethyl siloxane, bamboo, and coconut coir. The laser cutting process is used which also helps the Poly Dimethyl Siloxane (PDMS) to have selective areas for supply of oxygen. Accordingly, cutting of the said three materials are performed and are sent forward for the next step. Step 4 - Sewing:

The cutouts are brought to perform the step 4 i.e. sewing. Based on the model selected by the user the layers are sewed to together to form a sole (10) of the present application. The sewing of the layers together is perform by various sub steps like skiving, stamping, folding, applying glue, bonding work pieces, stitching and applying the attachments.

In the skiving step, skiving is the process used in crafting to reduce the thickness of material, especially in areas which are to be bent or folded and which must be pliable without becoming weakened. Skiving is also used when two edges of material are to be joined, so as to keep the overlapping area from becoming unnecessarily bulky. Thus, the skiving of the selected layer is performed. Followed by skiving, stamping, and folding are performed on the skived layers to obtain the desired shape of the insole. Glue is applied on the folded layer to stick the layers one above and to maintain the shape of the insole. Applying glue helps the bonding of the work pieces and layers remains intact with the each other. To avoid the loosing of the sole and the said layers should remain intact; a stitching is also performed on the glued layers. The stitching results in strong bonding of the layers and has an advantage that the even if the glue loses its sticking property the stitching helps the layer to remain intact and the shape is not disoriented. Other attachments are then attached to complete the insole design. After the sewing step, the unfinished product is supplied to the finishing process.

Once the insole (10) is finalized and stitched, it is combined with other shoe materials for making the final footwear product.

Step 5 - Finishing:

The finishing step is mainly performed to get the product market ready. The unfished product from the sewing step is further polished and made presentable so that the user can wear the footwear comprising insole (10). Polishing/ brushing/ greasing/ waxing are performed on the product. Further, if any excess glue is present on the sole, it is removed and if any part has been left to apply glue, glue is applied. Again, the bonding is performed on the finishing insole and remaining details are given or remaining accessories are applied to the final product. Step 6 - Packing:

The final product is then packed and is ready for the user to use the footwear product comprising the insole (10).

Yet in another aspect of the present invention, the method for treatment of the DFU using the shoe insole (10) as described above and footwear product manufactured therefrom. The method for healing the DFU is performed using the shoe insole (10). The said insole comprises of a first layer (1) of poly dimethyl siloxane, where the first layer comprise of a selective laser machined areas for supply of oxygen. The second layer (2) of bamboo employed for increased supply of oxygen and the third layer (3) of coconut coir employed for providing structural support, stability, and firmness to the sole. A method for healing the Diabetic Foot Ulcers (DFUs) using a shoe insole (10) and footwear product manufactured therefrom, wherein the method of healing of DFUs comprises:

(a) providing a shoe comprising a shoe insole (10) to an individual having foot ulcer or DFUs;

(b) wearing the shoe comprising the shoe insole (10);

(c) facilitating oxygen supply to the ulcerated area (U) of the individual’s foot (F) by the shoe insole (10) of the shoe;

(d) increasing oxygen in cells and blood by supplying oxygen through the passage channel (C) of the shoe insole (10) to the ulcerated area (U) wherein the carbon dioxide is taken by the bamboo layer of insole (10) and the bamboo layer releases oxygen which is taken up by cells in the ulcer area (U), and thus increasing oxygen level in the ulcer area and blood;

(e) reducing swelling, controlling infection, and stimulating growth of new cells and blood vessels; and

(f) healing and recovery of foot ulcer (U) and/or DFUs of the shoe wearer.

In another aspect of the present invention is to provide a footwear product for wearing having ability to naturally heal the foot ulcers. In Fig. 5, 10- Shoe insole; S- Shoe covering; F- Foot; 1- First layer; 2- Second layer; 3- Third layer. The footwear product is any form of the footwear like shoes, sandals etc. In one embodiment of the present invention. The footwear disclosed as a shoe as shown in Fig. 5. The shoe comprises of a shoe covering (S) which covers the foot (F) of the wearer and keep the shoe remain attached with the foot of wearer; and a shoe sole (10) attached in the shoe covering (S) which acts as a base, provide support, protect foot, and naturally helps in healing the foot ulcer of the wearer. The said shoe sole (10) is same as described in the above aspect. The said shoe sole (10) comprises of a first layer (1) of poly dimethyl siloxane (PDMS) where the first layer (1) of PDMS comprises a selective laser machined areas that face with the ulcer area (U) (as shown in figure 2) and provide a passage channel (C) (as shown in figure 2) for supply of oxygen, a second layer (2) of bamboo where the second layer (2) of bamboo provides and supply oxygen to the ulcer area (U) through the passage channel (C); and a third layer (3) of coconut coir, where the third layer (3) of coconut coir provides structural support, stability and firmness to the sole. Further, the second layer (2) of bamboo provides and supply oxygen to the ulcer area (U) through the passage channel (C). Optionally a fourth layer of foam is also attached in the shoe sole.

The novel and inventive features of the present invention include:

The Anaerobic infections are the most common causes due to lack of oxygenation in the tissues. Thus, the Shoe insole (BioCure InSole) prevents pressure points and also provides selective oxygen supply.

Shoe insole (BioCure InSole) is made of naturally occurring products with no chemical additions.

The product of the present invention is an insole cum treatment to patients. These prevent progressive stiffening of collagen containing tissue (cheiroarthropathy) and can stop further thickening of the skin and loss of joint mobility.

Peripheral Arterial Disease (PAD) can significantly delay healing and increase amputation risk in an established DFU. PAD infection is difficult to treat, as antibiotics cannot be delivered to the site from time to time. The Shoe insole (BioCure InSole) of the present invention is an easy wear and removal is also simple. It can be worn at home by the patient without anyone’s aid.

Because diabetic footwear is effective in reducing plantar foot pressures, the present invention Shoe insole (BioCure InSole) can serve as an important tool in the prevention of early stage DFU's; This sole is easily wearable, adaptable by an early patient. This can have improved compliance as a diabetic footwear as lifestyle change adaptability is not a big issue with this product.

The advantages of the following invention include:

1. Helps in healing the DFUs by selective supply of oxygen produced from bamboo. 2. All the materials used in the respective layers are eco-friendly. The product is made of biodegradable materials.

3. The product can be economically manufactured and can be made available to common public relatively at low price. 4. The insole is easy to manufacture and can be taken up as a village level activity.

5. The design is sustainable in nature and self-generating device that does not require any external power such as battery. The shoe insole (10) of the present invention is easily wearable and adaptable by an early patient. This can have improved compliance as a diabetic footwear as lifestyle change adaptability is not a big issue with this product.