Patent Publication Number: US-2010126514-A1

Title: Leg lift device and associated method

Description:
This application is a continuation-in-part application from application Ser. No. 12/120,430, filed May 1. 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/974,798, filed on Sep. 24, 2007. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     The present invention relates generally to the physical rehabilitation field and, more particularly, to a leg lift device and associated method for reducing the physiological strain placed on the knees, hip and back when walking with a fracture walker, cast boot, thick soled wound healing shoe or the like. 
     BACKGROUND OF THE INVENTION 
     The recent use of fracture orthotic walkers has been a very common therapy modality for multiple types of lower leg and foot injuries. A frequent complaint of patients that are utilizing this device is that it causes a marked inequality of limb length resulting in pain or injury to other areas of the body. Knee, hip and even back pain are frequently an untoward effect of these walker boots. A similar problem arises in patients or individuals walking in a cast boot or a thick soled wound healing shoe. The added height of the cast boot or wound healing shoe worn on the foot of an individual&#39;s injured limb compared to a standard shoe worn on the foot of an individual&#39;s uninjured limb creates an unlevel condition that produces stress upon various body joints and the back. Inside shoe devices, such as heel lifts, are less physiological in function and often do not provide adequate lift to completely compensate for the induced limb length discrepancy. Accordingly, such devices are not true solutions for the problem. 
     Recognizing this, prosthetists and physicians are currently treating lower limb length discrepancies by fixing a block or platform to the sole of a shoe with adhesives. It should be appreciated that this is a permanent method of applying a platform resulting in one pair of corrective shoes. This usually requires a visit to a prosthetist or shoe maker to be fitted for and to fabricate the corrective shoe. Following treatment, the corrective shoe can no longer be used by the individual. This waste and expense is avoided using the device and method of the present invention. 
     More specifically, the present invention is easily applied temporarily to a shoe by the consumer or patient. No special shoe or shoes need to be purchased. Further, following recovery, the individual or patient can simply remove the device from the shoe thereby restoring the shoe for normal use. 
     SUMMARY OF THE INVENTION 
     In accordance with the purposes of the present invention as described herein, there is provided a method of reducing physiological strain on a patient comprising: 
     one leg of the patient having thereon a therapeutic device for applying a therapeutic effect to the first leg, the therapeutic device being arranged such that the foot of the first leg of the patient is supported at a position spaced from the ground by a first distance when walking; 
     the foot of the other leg of the patient having thereon a shoe, the show being arranged to define a second distance of the foot of the second leg from a bottom of the shoe; and 
     providing a leg lift device for attachment to the shoe, comprising: 
     a sole plate arranged to engage underneath the shoe for engaging the ground beneath the shoe, the sole plate defining a first lift distance by which the shoe is raised from the ground; 
     a flexible shoe receiver attached to said sole plate around a periphery of said sole plate, said receiver including a first section to releasably engage over a toe of the shoe and a second section to releasably engage around a heel of the shoe such that the flexible shoe receiver engages around the shoe to hold the sole plate onto the shoe to remain in place between the shoe and the ground during walking, the shoe being readily removable from the flexible shoe receiver; 
     and a lift insert piece arranged to be inserted between the shoe and the sole plate and arranged to remain in place during walking so as to provide a support for at least a part of the foot of the patient while wearing the shoe during walking, the lift insert piece defining a second lift distance by which the shoe is raised from the ground; 
     and reducing the physiological strain placed on the knees, hip and back of the patient when walking by arranging the therapeutic device and the leg lift device such that the first distance is substantially equal to the sum of the second distance, the first lift distance and the second lift distance. 
     Preferably there is provided an attachment strap connected across the top band from one side to an opposed side. 
     Preferably is provided between said sole plate and said lift insert piece at least one co-operating engagement arrangement to hold the lift insert piece in place on said sole plate and beneath said shoe during walking. 
     Preferably said co-operating engagement arrangement comprises a recess on one of said sole plate and said lift insert piece and a co-operating projection on the other of said sole plate and said lift insert piece. 
     Preferably there are at least two co-operating engagement arrangements each comprises a recess on one of said sole plate and said lift insert piece and a co-operating projection on the other of said sole plate and said lift insert piece. 
     Preferably the shoe receiver is an open web made from an elastomeric material including a top band engaged around the shoe and a plurality of separate lugs extending from the top band to the sole plate. 
     Preferably the shoe receiver is made from a material selected from a group consisting of thermoplastic elastomer (TPE), rubber, latex, synthetic elastomer and combinations thereof. 
     Preferably the lift insert piece has a main support section with side edges spaced sufficiently to support a main part of the shoe of the patient, and the lift insert piece has a transverse front edge recessed rearwardly from a front edge of the sole plate. 
     Preferably the location of the recessed front edge is such that it is proximal to the metatarso-phalangeal joints of the foot of the patient. 
     Preferably the location of the recessed front edge is such that it is at or within 0.5 inches behind the metatarso-phalangeal joints of the foot of the patient. 
     Preferably the location of the recessed front edge is such that it allows decreased weight bearing pressure on the ball of foot while placing more contact on the mid foot and heel areas. 
     As an alternative, the lift insert piece has a rear edge recessed forwardly from a rear edge of the sole plate. 
     Preferably the location of the recessed rear edge is such that it is forward of the lowest point of the calcaneus of the foot of the patient. 
     Preferably the location of the recessed rear edge is such that it is at or within 0.5 inches forward of the lowest point of the calcaneus of the foot of the patient. 
     Preferably the location of the recessed rear edge is such that it allows decreased weight bearing pressure on the heel of the foot while placing more contact on the mid foot and ball. 
     According to a second aspect of the invention there is provided a method of reducing physiological strain on a patient comprising: 
     placing on one foot of the patient a shoe; and 
     providing a leg lift device for attachment to the shoe, comprising: 
     a sole plate arranged to engage underneath the shoe for engaging the ground beneath the shoe; 
     a flexible shoe receiver attached to said sole plate around a periphery of said sole plate, said receiver including a first section to releasably engage over a toe of the shoe and a second section to releasably engage around a heel of the shoe such that the flexible shoe receiver engages around the shoe to hold the sole plate onto the shoe to remain in place between the shoe and the ground during walking, the shoe being readily removable from the flexible shoe receiver; 
     and a lift insert piece arranged to be inserted between the shoe and the sole plate and arranged to remain in place during walking so as to provide a support for at least a part of the foot of the patient while wearing the shoe during walking; 
     wherein the lift insert piece has a main support section with side edges spaced sufficiently apart to support a main part of the shoe of the patient; 
     and wherein the lift insert piece has a transverse edge recessed from a corresponding edge of the sole plate. 
     According to a third aspect of the invention there is provided an apparatus for therapeutic treatment of a patient comprising: 
     a shoe engagement device for attachment to a shoe, comprising: 
     a sole plate arranged to engage underneath the shoe for engaging the ground beneath the shoe; 
     a flexible shoe receiver attached to said sole plate around a periphery of said sole plate, said receiver including a first section to releasably engage over a toe of the shoe and a second section to releasably engage around a heel of the shoe such that the flexible shoe receiver engages around the shoe to hold the sole plate onto the shoe to remain in place between the shoe and the ground during walking, the shoe being readily removable from the flexible shoe receiver; 
     and a lift insert piece arranged to be inserted between the shoe and the sole plate and arranged to remain in place during walking; 
     wherein the lift insert piece has a main support section with side edges spaced sufficiently apart to support a main part of the shoe of the patient; 
     and wherein the lift insert piece has a transverse edge recessed from a corresponding edge of the sole plate. 
     More specifically describing the invention the shoe receiver is an open web or mesh made from an elastomeric material. Such a material may be selected from a group consisting of thermoplastic elastomer (TPE), rubber, latex or other synthetic elastomer and combinations thereof suitable for the intended purpose. 
     Further describing the invention the sole includes at least two recesses. The lift insert includes at least two projections that are received in and engage the recesses in the sole. Each lift insert has a profile substantially matching the sole and a thickness of between about 1.0 and about 5.0 cm and more typically between about 1.0 and about 2.0 cm. Lift inserts of different thicknesses or heights may be interchangeably connected to the sole in order to provide a leg lift device of the desired height to match the height of the fracture walker, cast boot or fixed soled wound healing shoe worn on the other foot of the user. 
     In accordance with an additional aspect of the present invention, a method is provided for reducing the physiological strain on an individual associated with walking when a fracture walker, cast boot or thick soled wound healing shoe is worn on a first foot by an individual. The method may be broadly described as comprising detachably connecting a leg lift device to a shoe worn on the second foot of an individual. The method may be further described as including the step of adjusting a height of a leg lift device worn on the second foot to substantially match the height of the fracture walker, cast boot or wound healing shoe worn on the first foot. This is done by selecting a lift insert of desired height or thickness from a series of lift inserts of differing heights and securing the selected lift insert to the sole of the leg lift device. 
     Still further, the method may be described as including the step of inserting a shoe to be worn on the second foot into the leg lift device and attaching the leg lift device to the shoe. Further, the method may include removing the shoe from the leg lift device as desired. Still further, the method may include inserting a different shoe into the leg lift device and attaching the leg lift device to the different shoe. The device may be adjusted to compensate for any difference in sole height between the first and second shoes by changing the lift insert used in the device. In this way, it is possible for the user to increase the height of any number of shoes owned by the user to substantially match the height of the fracture walker, cast boot or thick soled wound healing shoe so as to allow the user to walk in a level attitude using many different shoes owned by the individual and appropriate for wear at a particular occasion. 
     In the following description there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings incorporated herein and forming a part of the specification, illustrate several aspects of the present invention and together with the description serve to explain certain principles of the invention. In the drawings: 
         FIG. 1  is a perspective view of the leg lift device of the present invention. 
         FIG. 2  is a right side elevational view of the leg lift device illustrated in  FIG. 1 . 
         FIG. 3  shows in combination the therapeutic device to be used on the leg to be treated together with a left side elevational view of the leg lift device holding a shoe of a user. 
         FIG. 4  is a top plan view of the sole of the device showing the recesses or apertures provided in the face thereof. 
         FIG. 5  is a bottom plan view of a lift insert for the device showing the projections provided on the bottom face thereof that are received in the recesses provided in the upper face of the sole. 
         FIG. 6  is a detailed cross sectional view showing one of the projections on the lift insert received in one of the recesses or apertures provided in the sole. 
         FIG. 7  is an isometric view similar to that of  FIG. 1  of a modified arrangement. 
         FIG. 8  is a side elevational view similar to that of  FIG. 3  showing the modified arrangement of  FIG. 7 . 
     
    
    
     Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. 
     DETAILED DESCRIPTION 
     Reference is now made to  FIGS. 1 and 2  illustrating the leg lift device  10  of the present invention. The leg lift device  10  comprises a sole  12 , including first and second sections  14   a ,  14   b , and a shoe receiver  16 . The shoe receiver  16  may take the form of a mesh or web and includes a first section  18  to engage a toe of a shoe and a second section  20  to engage a heel of a shoe (see also  FIG. 3 ). Typically the sole  12 , including both sections  14   a ,  14   b  is made from a material selected from a group consisting of ethylene vinyl acetate (EVA), polyphenylene ether (PPE) rubber and polymeric foam materials. The shoe receiver  16  is made from an elastomeric material. Such a material may be selected from a group consisting of thermoplastic elastomer (TPE), rubber, latex or other synthetic elastomeric material suitable for the intended purpose. 
     As illustrated, the shoe receiver  16  includes a series of lugs  22  that are secured to the sole  12  at spaced points between the sole sections  14   a ,  14   b . The shoe receiver  16  may be secured to the sole  12  at the lugs  22  by adhesive, heat welding or other appropriate means. 
     As further illustrated in  FIGS. 1 and 2 , the leg lift device  10  also includes a strap  24 . The strap  24  is connected at a first end to a metal loop  26  that is secured to the shoe receiver  16  by the connector  28 . The strap  24  is then looped through an aperture or opening  25  (see  FIG. 2 ) in the opposite side of the shoe receiver  16 . A fastener  30  such as a hook and loop fastener allows the strap  24  to be secured in position. 
     As best illustrated in  FIGS. 2-5 , it should be appreciated that the leg lift device  10  includes an optional lift insert  40  also made from a cushioning, elastomeric material. More specifically, each lift insert  40  includes a profile or outline matching the sole  12 . As best illustrated in  FIG. 4 , the top face  42  of the sole  12  (and more specifically, sole section  14   a ) includes two or more spaced recesses or apertures  44 . As best illustrated in  FIG. 5 , the bottom face  46  of the lift insert  40  includes two or more spaced projections  48 . When the lift insert  40  is property connected to the sole  12  of the device  10 , the projections  48  are received within and engage the apertures  44  and the outer periphery of the insert  40  and the sole  12  match (see also  FIG. 6 ). 
     Each insert  40  may have a thickness or height of between about 1.0 and about 5.0 cm and more typically between about 1.0 and about 2.0 cm. Each device  10  may include multiple lift inserts  40  with each insert having a different thickness or height. Each of the lift inserts  40  may be interchangeably connected to the sole  12  of the device  10 . Thus, by selecting a lift insert  40  of proper height, it is possible to match the height of the device  10  to the height of the fracture walking cast boot or healing shoe and thereby fully compensate for the leg length discrepancy characteristic of that device. For example,  FIG. 6  discloses a first lift insert  40  of thickness T 1  in full line and a second lift insert  40 ′ of greater height or thickness T 2  in phantom line. 
     In  FIG. 3  the therapeutic device indicated at D and defined by the fracture walking cast, boot or healing shoe is arranged such that the foot of the first leg of the patient is supported at a position spaced from the ground by a first distance D 1  when walking. The shoe S defines a second distance D 2  of the foot of the second leg from a bottom of the shoe. 
     The sole plate  12  defines a first lift distance D 3  by which the shoe is raised from the ground. The lift insert piece  40  defines a thickness or a second lift distance D 4  by which the shoe is raised from the ground. As explained previously, if the optional lift insert  40  is used, the first distance D 1  is substantially equal to the sum of the second distance D 2  and the first lift distance D 3 . If the lift insert  40  is not used, the first distance D 1  is substantially equal to the sum of the second distance D 2 , the first lift distance D 3  and the second lift distance D 4  so as to reduce the physiological strain placed on the knees, hip and back of the patient when walking. 
     In use, the strap  24  is opened and the leg lift device  10  is connected to a shoe S (see  FIG. 3 ). More specifically, the shoe S is positioned with the sole of the shoe against the lift insert  40 . As noted, the toe T of the shoe S is engaged under the first section  18  of the shoe receiver  16  while the heel H is engaged by the second section  20 . Since the shoe receiver  16  is made from elastomeric material, it readily stretches to receive the shoe S. The resilient memory of the elastomeric material then ensures that the shoe receiver  16  tightly engages the shoe S so as to hold the shoe S firmly on the shoe support  14 . The strap  24  is then pulled tight and fastened by means of the hook and loop fastener  30  in order to complete the connection of the leg lift device  10  to the shoe S. 
     The leg lift device  10  of the present invention is used in a method of reducing the physiological strain on an individual associated with walking when a fracture boot, cast boot or thick soled wound healing shoe is worn on a first foot by that individual. The method comprises detachably connecting the leg lift device  10  to the shoe S worn on the second foot of the individual. Toward this end, the method includes adjusting the height of the leg lift device  10  worn on the second foot so that the combined sole height of the shoe S and the device  10  substantially matches the height of the fracture walker, cast boot or wound healing shoe worn on the first foot. This is done by connecting a lift insert  40  of desired height to the sole  12  so as to form a device  10  of overall height substantially matching the height of the fracture walker, cast booth or thick soled wound healing shoe worn on the first foot by the individual. By providing a shoe height for the off leg substantially corresponding to the height of the fracture walker, cast booth or thick soled wound healing shoe for the leg undergoing treatment, the walking height between the two legs is substantially leveled. This reduces or substantially eliminates strain that would otherwise be placed on the joints of the individual including the knee and hip as well as the back. 
     Advantageously, the leg lift device  10  is easily detachable and may be used on a number of different shoes thereby allowing the user to wear different shoes for different occasions as desired without permanently altering any shoe. Significantly, the device  10  allows for use even when the selected shoes are of totally different sole heights. For example, a fracture walker worn on the foot of an injured limb has an overall sole height of 10 cm. A tennis shoe worn on the foot of the uninjured limb has an overall sole height of 3 cm. To compensate for the height of the fracture walker, the device  10  is provided with an overall sole height of 7 cm when worn with the 3 cm tall tennis shoe. Where the sole  12  of the device has a sole height or thickness of 3 cm, the lift insert  40  used has a height or thickness of 4 cms. 
     If the user later decides to wear a dress shoe having a sole height of 5 cm instead of the tennis shoe with a sole height of 3 cm, the device  10  is able to compensate for the difference. Specifically, the lift insert  40  with a height of 4 cms is removed from the device  10  and replaced with a lift insert  40  having a sole height of 2 cm. 
     Advantageously, the device  10  and method of the present invention allow, the user flexibility of wearing different shoes as desired and no shoe is permanently altered. Since the shoes are not permanently modified, they may still be used following treatment and removal of the fracture walker, cast boot or thick soled wound healing shoe. 
     Turning now to the device shown in  FIGS. 7 and 8  and to the views of the anatomy of the foot as shown in  FIGS. 9 and 10 , there is shown a modified arrangement similar to that previously described. The modification relates to the lift insert piece  401 . This piece is attached into the sole plate as previously described using the projections  48  and recesses  44  which act as a friction fit to hold these pieces together during walking and prevents the lift insert from sliding out from on top of the sole plate. The lift insert  401  extends to the rear and sides of the sole plate where it is substantially co-extensive therewith the sole plate so as to support the sole of the shoe fully in these areas. 
     However the lift insert  401  is shorter than the length of the sole plate  12  so that it has a transverse edge  402  or  403  which is spaced from the corresponding edge of the sole plate  12 . This transverse edge can be located at the front as indicated at  402  or at the rear as indicated at  403 . It is not intended that the length of the lift insert be reduced or recessed at both ends. Thus the front edge  402  is recessed rearwardly of the front edge of the sole plate and therefore rearwardly of the front edge of the shoe S resting on the lift insert. 
     The location of the cut front edge  402  is such that it is approximately aligned just behind (proximal) to the metatarso-phalangeal joints. This modification allows decreased weight bearing pressure on the ball of foot while placing more contact on the mid foot and rear foot (heel) areas. 
     Thus the location of the recessed front edge  402  is such that it is at or within 0.5 inches behind the metatarso-phalangeal joints of the foot of the patient. This location of the recessed front edge is such that it allows decreased weight bearing pressure on the ball of foot while placing more contact on the mid foot and heel areas. 
     In the alternative, the lift insert piece has the rear edge  403  recessed forwardly from a rear edge of the sole plate with the location of the recessed rear edge such that it is forward of the lowest point of the calcaneus of the foot of the patient, that is, it is at or within 0.5 inches forward of the lowest point of the calcaneus of the foot of the patient. This location of the recessed rear edge is such that it allows decreased weight bearing pressure on the heel of the foot while placing more contact on the mid foot and ball. 
     This location of the transverse edge can be formed by providing a lift insert piece which is pre-formed so that each kit of parts includes the sole plate and a series of lift insert pieces two of which are arranged to provide the front and rear recess respectively. Alternatively the doctor or the patient can take the existing full length insert piece and cut it a line marked on the piece. 
     This thickness of the lift insert is preferably of the order of 1 to 2 cm. This causes the forward end of the metatarsals to drop by the same distance of approximately 1 to 2 cm or less bearing in mind that the shoe remains in place covering the foot of the wearer and thus the resilience of the show will absorb some of the tendency to fall. 
     The purpose of the construction by which the forward part of the lift insert is removed is to reduce weight bearing pressure from the ball of the foot or from the heel of the foot. This can be used for patients who have ulcerated areas on the foot for example due to the reduction in blood circulation caused by diabetes. 
     The location of the front edge can vary between 3 to 15 cm depending on the area that is intended to off-load and the size of the device i.e. small, medium, or large. 
     The lift insert of formed of a resilient material but one of sufficient stiffness that the top surface remains spaced from the top surface of the sole plate so as to provide a drop a the front edge of the sole plate of at least 1 cm. 
     The shoe receiver  16  is formed by a top band  161  which extends around the periphery of the sole plate at a position spaced slightly inwardly of the sole plate so as to remain engaged over the shoe S. The band  161  includes a raised front portion  162  which extends over the toe of the shoe S. The band  161  includes a raised rear portion  163  in the form of an arch which extends around the heel of the shoe S. The front portion  162  is connected to the front end of the sole plate by a pair of the lugs  22  as indicated at  221  and  222  each of a respective side of the front portion. The rear portion  163  is connected to the rear end of the sole plate by a pair of the lugs  22  as indicated at  223  and  224  each of a respective side of the rear portion. The band  161  is connected to the sole plate along its sides by two of the lugs  22  as indicated at  225  and  226 , one just in front of the heel and one at the sides of the ball of the foot. The strap  24  is connected to the band  161  at a position just behind the front lugs  226  so as to extend over the arch of the foot and so that the strap cannot slide forwardly as it is confined by the lug  226 . Apart of the lugs, the band is separate from the sole plate with openings underneath the band and between the lugs. The lugs are connected to the sole plate by welding or by insertion between upper and lower layers of the sole plate where the lugs are retained in place by adhesive. 
     The foregoing description of the preferred embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. The drawings and preferred embodiments do not and are not intended to limit the ordinary meaning of the claims in their fair and broad interpretation in any way.