Patent Publication Number: US-2016242497-A1

Title: Shoe-leveling insole

Description:
This application claims the benefit of Provisional Patent Application Ser. No. 62/118,456, filed Feb. 19, 2015. 
    
    
     BACKGROUND 
     1. Field of Invention 
     This invention relates to shoe insoles, specifically to such insoles which are used to replace, or place on top of, insoles that are used in the raised-heeled shoe construction. 
     2. Description of Prior Art 
     Shoe manufacturers commonly provide consumers with various shoe styles and designs with varying heel heights. Some shoes are constructed to provide a relatively flat footbed for the user, meaning that when the human foot is in the shoe, the forefoot region of the foot is positioned at approximately the same height from the ground surface, as the heel portion of the foot. Other shoe designs provide for a raised-heel construction, meaning that when the human foot is in the shoe, the forefoot region of the foot is lower than the heel portion of the foot. Most shoes provide an insole that covers the footbed of the shoe, in order to help cushion or support the foot, when wearing the shoe. 
     Throughout the years, a raised-heeled shoe design may have been viewed by many as simply a fashion choice, as the deleterious affects of raised-heeled footwear on the structure and function of the human foot and body may not have been fully recognized at the time. However, today, there are numerous studies and clinical evidence of the potentially harmful effects of wearing raised-heeled shoes. Wolff&#39;s Law of bone and soft-tissue remodeling states that, “bone and soft-tissue remodel according to the stresses imposed upon the tissues.” Thusly, dependant upon the biomechanical forces applied to the foot and body, the body&#39;s reformation will be influenced at least in part, according to the stresses imposed by the shoe, and or the forces applied to the foot and body. 
     We already know of many clinical conditions of the human foot such as hallux valgus, bunions, plantar fascitis, flat foot and hammer toes, that in some cases, may directly result from either ill-fitting or poorly designed footwear or shoes, most commonly from a raised-heeled shoe design. Body posture may also be directly related to human foot structure and function, as the feet are the foundation of the skeletal frame, and contain various neurological reflexes for orienting the positioning of the human body. Faulty biomechanical function of the human foot and body may contribute to premature degenerative changes in the tissues affected. It is for these reasons, as well as an issue of overall comfort of the shod foot, and an attempt to restore the body to a more natural, biomechanical state and shape, that it becomes important to attempt to level the foot when wearing shoes. 
     With advancements in footwear technology and design, various insoles have been provided for the consumer, in order to attempt to help improve comfort and support of the human foot when wearing shoes. However, all the insoles heretofore known, suffer from several primary disadvantages: 
     (a) Manufacturers of insoles do not provide an insole that is designed to level the foot, from heel to forefoot, when wearing raised-heeled shoes; 
     (b) Manufacturers of insoles typically provide various components to the insole that raise the heel portion of the insole and thusly the foot, increasing the heel-height; 
     (c) Manufacturers of insoles do not provide a negative-heel insole, meaning that the forefoot is thicker than the heel region, to either replace or set on top of the existing insole of raised-heeled shoes. 
     (d) Manufacturers of insoles do not attempt to improve the natural biomechanics of the human foot and body by leveling the foot while wearing raised-heeled shoes. 
     OBJECTS AND ADVANTAGES 
     Accordingly, several objects and advantages of the present invention are: 
     (a) to provide an insole for raised-heeled shoes, that can approximately level the human foot from heel to forefoot, when wearing the shoe; 
     (b) to provide an insole for raised-heeled shoes that can be molded to various thickness ratios in the heel and forefoot regions, in order to accommodate a variety of heel-heights, provided by raised-heeled shoes; 
     (c) to provide a negative-heel insole, meaning that the forefoot is thicker than the heel region, to either replace or set on top of the existing insole of raised-heeled shoes. 
     (d) to provide a negative-heel insole, in order to attempt to improve the natural biomechanics of the human foot and body, by leveling the foot while wearing shoes. 
     Further objects and advantages are to provide an insole which can be easily manufactured to conform to the human foot with various material selection options, while providing comfort and support, by simply leveling the foundation of the human foot and body, when wearing raised-heeled shoes. Further objects and advantages will become apparent from a consideration of the ensuing description an drawings. 
    
    
     
       DRAWING FIGURES 
       All references pertaining to medial, lateral, superior, and inferior aspects of drawings or components, are based upon the standard anatomical position that is utilized to provide positioning references for human anatomical structures. The insole of the present invention shown in the drawings is for the right shoe of the individual user. 
         FIG. 1  shows a medial, superior, top, oblique perspective view of the insole. 
         FIG. 2  shows a lateral, superior, top, oblique perspective view of the insole. 
         FIG. 3  shows a medial, inferior, bottom, oblique perspective view of the insole. 
         FIG. 4  shows a lateral, inferior, bottom, oblique perspective view of the insole. 
         FIG. 5  shows a medial, inside, orthogonal view of the insole. 
         FIG. 6  shows a lateral, outside, orthogonal view of the insole. 
         FIG. 7  shows a superior, top, orthogonal view of the insole with delineation of cross section views. 
         FIG. 8  shows a medial, longitudinal cross section view, split at the approximate longitudinal heel and toe center line. 
         FIG. 9  shows a transverse cross section view, split at the approximate transverse, ball center line, traversing the medial and lateral aspects of the forefoot. 
         FIG. 10  shows a transverse cross section view, split at the approximate transverse, midfoot center line, traversing the medial and lateral longitudinal arches. 
         FIG. 11  shows a transverse cross section view, split at the approximate transverse, heel center line, traversing the medial and lateral aspects of the hindfoot. 
         FIG. 12  shows a medial, inferior, bottom, oblique perspective view of the insole, with added cushioning and support components bonded into the insole base bottom. 
     
    
    
     REFERENCE NUMERALS IN DRAWINGS 
       
     
       
         
           
               
               
               
               
             
               
                   
               
             
            
               
                 20 
                 fabric top 
                 30 
                 base 
               
               
                 32 
                 forefoot region 
                 34 
                 heel region 
               
               
                 35 
                 heel medial region 
                 36 
                 medial longitudinal arch region 
               
               
                 37 
                 heel lateral region 
                 38 
                 top central region 
               
               
                 39 
                 ball medial region 
                 40 
                 bottom central region 
               
               
                 41 
                 ball lateral region 
                 42 
                 forefoot ball cushioning pad 
               
               
                 44 
                 heel cushioning pad 
                 50 
                 heel cup posterior wall 
               
               
                 51 
                 heel cup medial sidewall 
                 52 
                 medial longitudinal arch wall 
               
               
                 53 
                 heel cup lateral sidewall 
                 54 
                 lateral longitudinal arch wall 
               
               
                 56 
                 midfoot support stabilizer 
                 57 
                 midfoot medial arch region 
               
               
                 58 
                 midfoot lateral arch region 
               
               
                   
               
            
           
         
       
     
     SUMMARY 
     In accordance with the present invention, a negative-heel insole comprising a substantially tapered body of material, having a predetermined thickness of the forefoot portion of the insole, being substantially thicker than the predetermined thickness of the heel portion of said insole. 
     DESCRIPTION 
     FIGS.  1  to  12   
     The human foot and ankle provide for a combination of flexibility and stability, due to the numerous bones in the feet (approximately 25% of all the bones in the body), and their various shapes. In general, the foot can be divided into three sections, regions, or portions, including the hindfoot, midfoot, and forefoot. The hindfoot includes the talus bone, forming the ankle joint, and the calcaneus bone, forming the heel. The midfoot consists of the tarsal bones, including the navicular bone, cuneiforms, and cuboid and contributes to the transverse arch. The forefoot consists of the metatarsals, also contributing to the transverse arch, and the phalanges. The medial longitudinal arch is formed by the calcaneal tuberosity, the talus, the navicular bone, three cuneiform bones, and the first, second, and third metatarsal bones. The lateral longitudinal arch is formed by the calcaneus, cuboid, and fourth and fifth metatarsal bones of the foot. The ball of the foot is a general term used to describe the padded forefoot portion of the foot between the toes and the midfoot transverse arch, and contributing arch regions. In general, the heel is the prominence at the inferior posterior portion of the hindfoot, formed by the calcaneus bone, or heel bone. 
     A typical embodiment of the foot and shoe-leveling insole of the present invention is illustrated in  FIG. 1  (medial, superior, top, oblique, perspective view) and  FIG. 2  (lateral, superior, top, oblique, perspective view). The insole has a thin fabric material top  20  of uniform thickness that is bonded to a thicker foam base  30 . Foam base  30  provides cushioning and support formation for the bone and soft-tissue elements of the human foot, including the medial and lateral longitudinal arches and transverse arch, as well as providing for a variable thickness between the corresponding forefoot region of the insole base and the heel region of the insole base. This variable thickness of the base  30  between the forefoot and the heel is utilized to create a heel portion of the insole that is lower, or thinner, than the forefoot portion of the insole, which is relatively higher, or thicker, than the heel portion of the insole. When the individual places this variable thickness insole into a shoe that is constructed with a relatively raised-heel shoe design (when heel height is compared to the forefoot height of the shoe), and the individual wears the shoes, the user&#39;s feet will be essentially level when standing or walking in the shoe. 
     In the preferred embodiment, the base is made of a flexible foam, such as polyurethane (PU) foam, or ethylene vinyl acetate (EVA) foam, or closed cell memory foam. However, the base can consist of any other materials that can be repeatedly bent or flexed without fracturing, such as polyethylene, rubber, leather, silicone, encased gel, etc. Typical injection molding or compression molding can be used for an ethylene vinyl acetate foam base. Cold pour polyurethane foam processes can be used for PU foam. The fabric top  20  can be made of various materials and thickness, bonded directly on top of the base  30  with adhesive. 
       FIGS. 1 to 4  shows the forefoot portion  32  of the insole, inclusive of the region of the insole beneath the metatarsal heads and the toes of the human foot, has an increased thickness, as opposed to the heel portion  34  of the insole, where the heel of the foot, most specifically the calcaneus bone, lies. This heel region is of a decreased thickness, relative to the forefoot region. This variable thickness as described above, gradually decreases its thickness from the forefoot region to the heel region of the insole. This base thickness variation can be visualized by comparing central portion base top surface  38 , to central portion base bottom surface  40 , as this central portion of the insole extends from the region of the insole that supports the forefoot, then through the midfoot, and finally extends to the region of the insole that supports the hindfoot. This thickness comparison can be visualized in  FIG. 1  through  FIG. 4 . However, optionally, the longitudinal medial arch region  36  of the insole, supporting the midfoot region of the foot, may temporarily increase the base thickness in the midfoot portion of the medial longitudinal arch region of the insole, in order to provide for a raised arch of varying heights, depending on the desired medial arch height of the insole. 
     The thickness of the insole will vary depending on the size of the insole used for fitting various shoe sizes. These variations in thickness are in accordance with standard methods of grading shoes and their insoles, in order to provide for the variety of shoe sizes. There may also be variations of insole thickness depending on the shoe type and heel height. Various heel heights are provided by shoe manufacturers, and obviously, depending on the heel height, not all shoes will be able to utilize the present insole invention, due to such factors as toe box height, which affects the amount of room available in the forefoot, inclusive of the toe region of the shoe. For example, if the heel height is too great, relative to the forefoot, then the foot cannot be leveled by the present invention insole, because the thickness increase in the forefoot region of the insole, necessary to level the heel height, will be too thick in the forefoot region, precluding the forefoot and toes to fit comfortably in the shoe. 
     In the typical embodiment for a Untied States of America (USA) men&#39;s size 11 standard width insole, with a 3 mm raised heel, relative to the ball or forefoot, the forefoot portion  32  of the insole base would measure approximately 6.5 millimeters (mm) in depth or thickness, while the heel portion  34  of the insole base would measure approximately 3.5 mm in depth or thickness. This variation in thickness longitudinally from the forefoot to the heel region of the insole, can be visualized in various cross sectional views, both longitudinally and transversely.  FIG. 9  shows a top orthogonal view of the insole, with four different cross sectional figure lines, one positioned longitudinally, and three transversely across the insole, indicating the regions that the four cross sectional views show in  FIG. 8  through  FIG. 11 .  FIG. 8  shows a cross sectional longitudinal view, as seen from the medial aspect. The slanted cross hatching lines indicate the various thickness of the insole as it progresses from heel to toe.  FIG. 9  is a transverse cross sectional view that shows the thickness of the insole, in the portion corresponding to the ball region of the forefoot.  FIG. 10  is a transverse cross sectional view that shows the thickness of the insole, in the portion corresponding to the medial and lateral longitudinal arch regions of the midfoot.  FIG. 11  is a transverse cross sectional view that shows the thickness of the insole, in the portion corresponding to the heel region of the hindfoot. 
     The fabric top portion  20  of the insole that is adhered to the insole base  30  can have a uniform thickness of approximately 0.5 mm to 1 mm or more, depending on preference. When measuring the thickness of the insole forefoot portion  32 , by measuring across, transversely, the metatarsal or forefoot portion (from the big toe, digit 1, to the little toe, digit 5), the thickness may vary from the first metatarsal to the fifth metatarsal, providing for any wedging preference that are at times utilized for insoles, in order to help prevent excessive pronation of the foot, when wearing shoes. Therefore, the medial side of the ball portion of the insole  39 , may increase its thickness of the medial side, when compared to that of the lateral side of the ball portion of the insole  41 . This same potential for creating a wedge in the corresponding forefoot portion of the insole, can also be used in the heel regions  34 , by increasing the thickness of the medial side of the heel portion  35  of the insole, relative to the lateral side of the heel portion  37 , in order to help decrease excessive foot pronation, emanating from the hindfoot. Whether or not the measured thickness from lateral to medial is increased in an embodiment of the insole or not, the central portion  38  of the insole, in the forefoot and heel regions, maintains an increased thickness longitudinally in the forefoot portion of the insole, relative to the heel portion of the insole, thereby maintaining the leveling effect on the shoe, as attained by the present insole invention, and thusly, leveling the foot when the shoe is worn with the leveling insole, as described herein. 
     The durometer or hardness of the insole base  30  may be of varying degrees or hardness, according to the user&#39;s or manufacturer&#39;s preference. Typical durometers may be of various densities and may range from approximately 5 degrees to 60 degrees, Shore A, when cast in the aforementioned material options, providing for a flexible, cushioned base. In addition to the aforementioned material options, a typical enclosed insole cushioning enhancer may be added to the bottom side of the base of the insole in the forefoot portion  42 , and cushioning enhancer  44  in the heel portion. The forefoot and heel cushioning enhancer components can be made of various materials, such as polyurethane elastomere, polyurethane foam, poliyou foam, rubber, silicone, encased gel, ethylene vinyl acetate (EVA) foam, etc. The durometer of hardness of these cushioning enhancer components may vary from 5 degrees to 50 degrees, Shore A. 
     In the preferred embodiment, a heel cup posterior backwall  50  is formed by the insole sidewalls extending upwards from the insole base  30 . Midfoot medial insole sidewall support  52  is formed by the continuation of the medial heel cup sidewall  51 , antero-medially alongside the insole, corresponding to the medial longitudinal arch region of the foot, and terminating in the medial ball region of the foot. Lateral midfoot insole sidewall support  54  is formed by the continuation of the lateral heel cup sidewall  53  antero-laterally alongside the insole, corresponding to the lateral longitudinal arch region of the foot, and terminating in the insole region, slightly anterior to the where the lateral base of the fifth metatarsal region of the foot would rest. 
     The corresponding medial longitudinal arch region  36  of the insole base  30  may increase its thickness, relative to the forefoot and heel portions of the insole, in order to provide for an enhanced, raised arch support for the medial longitudinal arch. As viewed in  FIG. 10 , the cross sectional view shows an increase in thickness of the insole transversely across the medial and lateral longitudinal arches of the midfoot, increasing the thickness from the thinner, lateral arch portion  58  of the insole, to the thicker, medial arch portion  57  of the insole. The insole base underlying the portion of the medial longitudinal arch region of the foot, may have additional support or cushioning, provided by midfoot and medial arch stabilizer  56 , bonded to insole base  30 . The medial arch stabilizer may be bonded or adhered to the underside of the insole base  30  with adhesive. The medial arch stabilizer  56  may be made of various materials, such as polyurethane elastomer, polyurethane foam, ethylene vinyl acetate foam, memory foam, poliyou foam, silicone, gel, leather, plastic, graphite, etc. The durometer or hardness of the medial arch stabilizer may vary from 5 degrees to 95 degrees, shore A, depending on the manufacturer&#39;s or user&#39;s preference. 
     Operation 
     The manner of using the foot and shoe leveling insole is identical to that for insoles in present use. Namely, one places the shoe-leveling insole of the present invention into the raised-heeled shoe, either on top of the insole that is already present in the shoe, or they may first remove the insole that is present in the shoe, and replace it with the shoe-leveling insole. Next, one places their feet into the shoes with the foot and shoe-leveling insoles, and then wears the shoes, providing for a relatively level foot position, meaning the heel portion of the foot and the forefoot portion of the foot are relatively, or approximately level during both stance and gait. 
     The individual using the foot and shoe leveling insoles will want to measure the heel height of the shoes that they intend to use the foot and shoe-leveling insoles. An approximate measurement can be attained by taking two separate measurements. One measurement is taken at the region of the shoe where the ball of the foot is located on the medial side, and one measurement is taken at the region of the shoe, where the heel of the foot is located on the medial side. If the individual plans to use the foot and shoe-leveling insole by removing the existing insoles of the shoes intended for use, then prior to measurement, the individual should remove the existing shoe insoles. If the individual will be using the foot and shoe-leveling insoles by placing them on top of the existing insoles, then the individual should leave the existing insoles inside of the shoes, during measurement. 
     The first measurement obtained, measures the thickness or vertical depth of the outsole and midsole portion of the shoe, located approximately at the area of the shoe that supports the infero-medial aspect of the ball region of the foot, on the medial side of the shoe, where the head of the first metatarsal bone lies on the footbed of the shoe. To note, some shoes do not have midsoles, or have the midsole portion of the shoe, bonded or molded as part of the outsole. In this example for obtaining measurement, we refer to a shoe that has either a bonded separate midsole and outsole, or a midsole that is molded as part of the outsole. If the shoe that the individual user selects does not have a midsole, then the same protocol can be used as described herein, using measurements from the outsole only. 
     In order to obtain the first measurement, in order to determine the relatively raised heel height of any shoe construction, the individual should place the tip of their index finger inside the shoe at this ball of the foot region, and push downward and outwards, towards the outside of the shoe, on the medial side, in order to contact the region of the shoe formed by the inside sidewall of the outsole, and the floor of the inside of the shoe. When pushing downwards and outwards at this portion of the shoe, the individual can feel and see from the outside of the shoe, where the forefoot, or ball of the foot sits in the shoe, as visualized from the outside. Next, the individual may take a ruler or similar measuring device, and place it against the outsole and midsole, and measure the thickness or depth of the outsole and midsole, now knowing where the floor of the inside of the shoe contacts the sidewall of the outsole and midsole. The individual will record this measurement, in order to compare it to the second measurement that will be taken of the heel portion of the shoe outsole and midsole thickness or depth. 
     The second measurement obtained, measures the thickness or vertical depth of the outsole and midsole portion of the shoe, in the heel region of the medial side of the shoe, where the longitudinal center of the calcaneus bone lies. In order to obtain this second measurement, the individual should place the tip of their index finger inside the shoe at this heel of the foot region, and push downward and outwards, in order to contact the region of the shoe formed by the inside sidewall of the outsole, and the floor of the inside of the shoe. When pushing downwards and outwards at this portion of the shoe, the individual can feel and see from the outside of the shoe, where the calcaneus, or heel portion of the foot sits in the shoe, as visualized from the outside. Now, the individual may take a ruler or similar measuring device, and place it against the outsole and midsole, and measure the thickness or depth of the outsole and midsole, now knowing where the floor of the inside of the shoe contacts the sidewall of the outsole and midsole. The individual will record this measurement, in order to compare it to the first measurement that was taken of the outsole and midsole thickness of the shoe, corresponding to the ball region of the foot. 
     In a raised-heeled shoe, the heel portion measurement of the outsole and midsole region will be thicker or deeper in thickness than the ball portion measurement of the outsole and midsole. In order to determine the difference in thickness between these two portions of the shoe, the individual can subtract the thickness measurement of the ball portion of the shoe outsole and midsole, from the thickness measurement of the heel portion of the shoe outsole and midsole. For example, a ball portion outsole and midsole measurement of 12 mm (millimeters) thickness, subtracted from a heel portion outsole and midsole measurement of 15 mm thickness, would determine that the raised-heeled shoe construction, in this case, would be a 3 mm raised heel difference. 
     Once the individual determines this raised-heel measurement difference, the individual would then know to select the foot and shoe-leveling insole of this present invention that would correct the raised-heel height difference. In this case of a 3 mm raised-heel difference, the individual would select the foot and shoe-leveling insole heel portion of the insole that is 3 mm lower in the heel, when compared to the forefoot portion of the insole. Thereby, when the individual will place the foot and shoe-leveling insole into the shoes that measured a 3 mm raised-heel difference shoe construction, the individual would obtain a relatively level foot during both stance and gait, as provided by the foot and shoe-leveling insole with a 3 mm correction, accomplished by a 3 mm thinner heel portion of the insole, when compared to the 3 mm thicker forefoot portion of the insole. The left side insole will be placed into the left shoe, and the right side insole will be placed into the right shoe, and the user will wear the shoes with shoe-leveling insoles of the present invention. 
     CONCLUSIONS, RAMIFICATIONS, AND SCOPE 
     Accordingly, the reader will see that the shoe-leveling insole of this invention can be used to level the human foot, meaning that the forefoot portion of the foot will be at approximately the same height from the ground, as the heel portion of the foot, when wearing raised-heeled footwear or shoes. In addition, the human body can maintain a more natural, biomechanical state and shape of the human body by providing a relatively level foundation for the human foot, when wearing the negative-heel insole of this invention, in their raised-heeled shoes. Furthermore, the shoe-leveling insole has the additional advantages in that
         it reduces aberrant biomechanical forces to the ball of the foot, commonly associated with hallux valgus deformity and bunion formation caused at least in part, if not whole, by wearing raised-heeled shoes;   it reduces aberrant biomechanical forces throughout the body, commonly associated with postural deficit, affected in some part by raised-heeled shoes; and   it provides shoe comfort improvement in many cases, due to the leveling of the foundation of the body, the feet.       

     Although the description above contains many specifics, these should not be construed as limiting the scope of the invention, but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example the shoe-leveling insole can be of variable thickness, in order to accommodate various raised heel-heights that shoe or footwear manufacturers provide. 
     Thus, the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.