U.S. patent application number 11/895284 was filed with the patent office on 2008-02-28 for cushioning insole adjustment kit.
Invention is credited to Soren Vindriis.
Application Number | 20080047164 11/895284 |
Document ID | / |
Family ID | 39112023 |
Filed Date | 2008-02-28 |
United States Patent
Application |
20080047164 |
Kind Code |
A1 |
Vindriis; Soren |
February 28, 2008 |
Cushioning insole adjustment kit
Abstract
Insole adjustment kit, the kit comprising an upper, elastic
cushioning insole layer and a lower, liquid filled insole layer
under the upper layer and at least one pocket between the upper
layer and the lower layer, the kit further comprising a number of
inserts dimensioned for insertion into the pocket, the inserts
having mutually different degrees of hardness.
Inventors: |
Vindriis; Soren; (Horsens,
DK) |
Correspondence
Address: |
JAMES C. WRAY
1493 CHAIN BRIDGE ROAD
SUITE 300
MCLEAN
VA
22101
US
|
Family ID: |
39112023 |
Appl. No.: |
11/895284 |
Filed: |
August 23, 2007 |
Current U.S.
Class: |
36/29 ; 36/43;
36/44 |
Current CPC
Class: |
A43B 7/1425 20130101;
A43B 7/1465 20130101; A43D 999/00 20130101; A43B 7/144 20130101;
A43B 7/147 20130101; A43B 7/1445 20130101; A43B 17/026
20130101 |
Class at
Publication: |
036/029 ;
036/043; 036/044 |
International
Class: |
A43B 13/20 20060101
A43B013/20; A43B 13/38 20060101 A43B013/38 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 23, 2006 |
EP |
06017513.0 |
Jan 22, 2007 |
EP |
07001306.5 |
Claims
1. Insole adjustment kit, the kit comprising an upper, elastic,
cushioning insole layer and a lower, liquid filled insole layer
under the upper layer and at least one pocket between the upper
layer and the lower layer, the kit further comprising a number of
inserts dimensioned for insertion into the pocket, the inserts
having mutually different degrees of hardness.
2. Insole adjustment kit according to claim 1, wherein the upper or
the lower layer or both are dimensioned to extend over the entire
sole of the foot.
3. Insole adjustment kit according to claim 1 or 2, wherein a
pocket is positioned under the heel of the foot.
4. Insole adjustment kit, wherein a pocket is located under the
middle of the foot.
5. Insole adjustment kit according to any preceding claim, wherein
the pocket is a recess extending into the underside of the upper
layer, the depth of the recess being less than the height of the
upper layer.
6. Insole adjustment kit according to claim 5, wherein a pocket is
accessible from the side of the upper layer.
7. Insole adjustment kit according to any preceding claim, wherein
at least one of the number of inserts has a region where the
compression resistance is lower than in the rest of the insert.
8. Insole adjustment kit according to claim 7, wherein the region
comprising a perforation through the insert.
9. Insole adjustment kit according to any preceding claim, wherein
at least some of the number of inserts are dimensioned for
insertion of at least two insert into the pocket.
10. Insole adjustment kit according to claim 9, wherein the two
inserts are dimensioned for insertion of a first insert above a
second insert, wherein the first has a lower hardness than the
second insert.
11. Insole adjustment kit according to claim 9 or 10, wherein the
second insert has a lateral extension less than the first
insert.
12. Insole adjustment kit according to claim 9, 10, or 11, wherein
the first insert has a first region where the compression
resistance is lower than in the rest of the first insert, wherein
the second insert has a second region where the compression
resistance is lower than in the rest of the second insert the first
and the second regions have different dimensions and an at least
partly overlap.
13. Insole adjustment kit according to any preceding claim, wherein
the inserts have a surface with glue which is covered by a cover
foil, the cover foil being configured for removal for insertion of
the insert into the pocket.
14. Insole adjustment kit according to claim 13, wherein the cover
foil is provided with information about the corresponding
insert.
15. Insole adjustment kit according to claim 13, wherein the
information comprises at least one of the following, the shoe size
related to the insert, the insert thickness, information about the
material of the insert, information indicating the elasticity of
the insert.
16. An insole adjustment kit according to claim 14 or 15 in
combination with a patient journal into which a cover foil is
placed for record of the application of the corresponding insert.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to insoles with wound healing
zones, predominantly for diabetes patients.
BACKGROUND OF THE INVENTION
[0002] Diabetes patients face a large risk to develop foot ulcers
(decubitus) due to reduced blood circulation in the legs and the
foot. Such wounds often lead to loss of job and social contact, and
for the society it implies large costs. Investigations have shown
that foot ulcers in the case of diabetics take on average 60 days
to heal and with correspondingly large costs for wound healing
medication and personnel during the healing period. Some wounds are
not able to heal and develop in such a way that amputation of the
foot or part of it is necessary. In Denmark, there are registered
in the order of 10,000 open wounds among diabetics every year, and
about 400 amputations are performed due to this cause.
[0003] U.S. Pat. No. 5,329,705 discloses a footgear with an inner
sole having a grid of removable, resilient elements to provide
relief to overloaded areas of the foot. The gear is all together a
rather complicated boot-like structure only available at relatively
high costs and impossible to integrate in a normal shoe. A
like-wise system is disclosed in the US-patent application
2003/0212358 also having a boot-like appearance. These complicated
structures illustrate the importance for diabetic patients and the
society to reduce the risk for wound development and for healing
the wounds most efficiently.
[0004] An improvement relatively to the rather bulky and
uncomfortable above-mentioned boot-like structures is disclosed in
the international patent application WO 02/34080 describing a
custom foot bed device constructed using a curable substrate which
is formed to the plantar surface of the foot except in the area
occupied by spacers designated to off-load the wounds on the bottom
of the boot. Though being an improvement on the general scale this
kind of foot bed has disadvantages which will be more clearly from
the following arguments.
[0005] The creation of wounds follows overload in the skin of the
foot sole. This overload occurs when the pressure level multiplied
by the time for this pressure level on a global area of the foot
sole surpasses the carrying capacity of the skin itself. In order
to prevent foot wounds, especially for diabetic patients, not only
the reduction of the pressure is important, but also a reduction of
the time for the load on the foot. When a local skin area under the
foot experiences a continuing load, the blood circulation to this
area is reduced, and the skin itself will die with time. For
diabetic patients, the situation is critical, because diabetes,
with time, reduces the blood circulation in the skin layer of the
foot, such that even very small, local loadings can reduce the
blood circulation in the skin itself at a rate that causes the
cells to die. Often, this situation implies a delamination of the
loaded skin layer, by which an inner cavity is created inside this
skin layer. The skin cells below this cavity will be dead to a
large extent, and the skin is loosing its flexibility. The result
is, typically, a skin with small cracks, through which bacteria
from the foot sole can get access into the hollow cavity in the
skin. This leads to an inner inflammation in the skin with the
result of a sudden open wound.
[0006] A further aggravation of the situation is the fact that
diabetic patients often develop inflammation in the nerves
(neoropathy) in the outermost ends of the nerves in the foot sole
which reduces or entirely removes the feeling sensation. A normal
feeling sensation in the foot sole automatically causes a person to
change the position or the orientation of the body when a local
area on the foot sole is subject to a critical load. This reduces
the time of the loading and prevents overloading to lead to
continuous damage of the foot. In contrast thereto, diabetic
patients loose this automatic reaction pattern when the feeling
sensation gets reduced or entirely removed due to nerve
inflammation. The consequence for the diabetic patient is that the
inflammation in the skin layers evolves without notice by the
patient.
[0007] In order to relief certain areas where wounds are developing
or have developed standardized, certain insoles have been
developed. U.S. Pat. No. 5,768,803 discloses an insole having a
bottom layer and a top layer where sections of the layers may be
removed to create an empty space directly beneath a corresponding
painful area of the foot. Even though this kink of insoles may
prevent further pressure on a critical area under the foot, the
remaining part of the foot is still exposed to the remaining load
without any solution of a regulated time of this load, thus,
fiddler wounds easily develop on the other foot.
[0008] Prior art standardized insoles have not yet had success on
the market, as they do not solve the problem with diabetic ulcers
on the foot in a satisfactory way. Therefore, most of the pressures
relieving insoles are, today, uniquely designed for each patient by
orthopaedic or medical personnel. However, these individually
constructed insoles have a number of disadvantages. For example,
the time for manufacture of the insoles is long, the insoles are
very expensive, insoles still do not reduce the loading time, the
insoles typically reduce the blood circulation in the foot of the
diabetic patient by fixating the foot, and the insoles are not
manufactured in collaboration with the personnel that controls the
skin of the patients foot, which makes the correct continuing
adjustment of the insole difficult. On top of this, most of the
individually adjusted insoles are constructed in a way to change
the point of load, for example, by moving the load from the heel
and the forefoot to the middle of the foot. The result is a
fixation of the foot with unwanted reduced blood circulation, and,
often the hip and the bag are loaded in an unsuitable way.
DESCRIPTION/SUMMARY OF THE INVENTION
[0009] It is, therefore, the purpose of the invention to provide an
insole for support of painful foot areas that is easy and fast to
adjust in accordance with the needs of the patient and which can be
provided at low cost. This purpose is achieved by an insole
adjustment kit comprising an upper, elastic, cushioning insole
layer and a lower, liquid filled insole layer under the upper layer
and at least one pocket between the upper layer and the lower
layer. The kit further comprising a number of inserts which are
dimensioned for insertion into the pocket. The inserts have
mutually different degrees of hardness.
[0010] An insole adjustment kit according to the invention has a
number of advantages. First of all, the different number of inserts
allows an individual adaptation to the needs of the user. Harder or
softer inserts may be used in order to distribute the load on the
foot over a larger or a smaller area. The liquid filled insole,
typically filled with water, is constructed such that, during load,
a hydraulic pressure is provided under the foot. This hydraulic
pressure reduces the pressure load on the foot sole by distributing
the pressure over a bigger area. In addition, the liquid filled
insole under the foot of the patient causes relatively large
movements of the foot, even during very small changes of the point
of gravity of the diabetic patient. As a consequence, the critical
kind of load on exposed local areas on the foot is reduced, which
is especially important if the diabetic patient has neoropathy.
[0011] The cushioning upper layer and the inserts with adoptable
cushioning inserts provide a three dimensional surface against the
foot sole, when the foot is standing on the insole, which results
in a larger supporting surface and a pressure equilibrium.
Furthermore, this three dimensional supporting surface acts on the
liquid filled layer, such that the pressure from the foot is
distributed over an even larger area, resulting in a relief of the
load against the foot sole, which is much larger by this
combination than the sum of the pressure relief by the cushioning
upper layer, the inserts or the liquid layer alone.
[0012] Preferably, the upper or the lower layers are both
dimensioned to extend over the entire sole of the foot. This is,
however, not strictly necessary, especially, if only part of the
foot is desired to provide a pressure relief Typically, the pocket
is positioned under the forefoot where a large part of the pressure
is experienced, or under the heel of the foot, or under both
depending on which area is desired to be relieved. If there are
wounds both on the forefoot and on the heel, an insole according to
the invention may still be of great help, even though the pressure
from the heel is transferred to the forefoot and the pressure from
the forefoot to the heel. The reason for this is that the steady
movement of the liquid from the forefoot to the heel and back
changes the pressure in the wounded areas continuously, such that
blood circulation is rather promoted than prohibited.
[0013] The pocket may also be placed in the middle of the foot with
openings towards the sides of the sole. This may be used for
establishing protection especially at the inner and outer side of
the middle part of the foot, a location causing problems especially
for heavy weight people.
[0014] As a conclusion, an insole according to the invention has a
number of advantages. First of all, the pronounced pressure
equalisation over a larger area has the effect of pressing relief
in the skin, which eases the blood circulation. Secondly, the
liquid filled layer increases the movement of the foot and the time
of load is reduced in this way. In addition, the increased movement
of the foot increases the blood circulation in the foot on a
general basis, such that the entire insole according to the
invention has a substantially prophylactic effect.
[0015] When pre-states of wounds occur under the foot of diabetic
patients, it is of utmost importance that a pressure relief is
performed immediately and that the relief can be adjusted
individually by competent personnel, in dependence of the skin of
the foot sole. Therefore, the system according to the invention is
designed in a way that the inserts are part of the kit and have
different hardness with corresponding cushioning properties.
[0016] In a practical embodiment the pocket is provided as a recess
extending into the underside of the upper layer. The depth of the
recess is less than the height of the upper layer, such that the
recess only extends partly into the upper layer and there is still
a part of the upper layer covering the recess.
[0017] The inserts are dimensioned to fit into the pockets, but may
have a thickness that is less than the pocket in order to combine
different inserts into the same pocket. For example, the inserts
may be dimensioned for insertion of a first insert with a lower
hardness than a second insert that is placed underneath the first
insert. In this case, the insole adjustment kit according to the
invention provides the possibility of a great variation of
adjustment in accordance with a need of a foot of a diabetic
patient or other kind of patient with pre-states of wounds under
the foot.
[0018] In order to achieve a pronounced relief of pressure on a
certain area under the foot, the inserts may be provided with a
region under the specific risk area for sore, where the compression
resistance is lower than in the rest of the insert. Such a reduced
compression resistance can be provided by a perforation through the
insert. A perforation in the insert is easily provided by the
medical or orthopaedic personnel during the adaptation of the
insole to the specific skin conditions of the foot of the
patient.
[0019] In order to optimize the pressure relieving properties of
the liquid filled insole, the pocket may be filled with a first,
upper insert and a harder, lower insert, where the second, lower
insert has a lateral extension less than the first insert. The
hard, second insert may be provided with a lateral extension that
is adapted to exert a pressure on the underlying liquid filled
insole to a correct degree as estimated or calculated by the
orthopaedic or medical personnel during adaptation of the insole.
Such an estimation or calculation may require some kind of
experience by the personnel, but once this experience has been
gained, the kit according to the invention contains the equipment
necessary for providing an insole within a very short time, for
example within an hour or less, which is almost immediately after
consultation of an expert by the patient searching pressure relief.
This minimises damage to the skin of the foot and prevents possible
sore creation and a later risk for a final amputation.
[0020] Instead of a perforation, the area of the sole may be
entirely relieved by providing a hole in the insert. Thus, the
region of the foot with the risk for a sore would only experience a
very light pressure of the upper layer, which is pressed into the
hole of the insert and where the insert presses upon the liquid
layer creating a pressure equalisation over a larger area without
exerting pressure on the sore.
[0021] The upper layer may suitable be provided by a polymer foam,
for example expanded ethylene-vinyl-acetate.
[0022] Liquid filled layers may be provided by production methods
as described in International patent applications WO97/03583,
WO01/08523, WO02/28216, WO01/08523 by Vindriis.
[0023] As an example, the inserts may be provided with glue on the
upper side in order to be fastened to the upper layer 101 or
provided with glue on the lower side in order to be fastened to the
lower layer. For transportation, this glue may be covered by a
removable foil, such as silicone paper or a suitable polymer
foil.
[0024] In order to provide a perforation or a through going hole
for reduction of pressure against the foot sole, the following
procedure may be applied. In the case of the glue being on the
upper side of the insert, the insert may be placed in the insole
for the opposite foot, in other words, an insert for the right foot
is placed in the upper layer of the left insole and vice versa. The
insole is then placed upside down such that the upper layer is
resting on the floor and the foil covered insert is facing with the
foil upwards. The foot sole of the patient is placed on top of the
foil and the location for a perforation or hole is marked with a
pen on the foil of the insert in the upside down placed insole. In
this case, the cover foil for the insert is provided with
information about the adaptation of the insole.
[0025] The cover foil once released from the insert may then be
used for documentation in a medical or orthopaedic journal of the
patient in order to minimise possible mistakes in the journal, in
as much as the cover foils are direct documentation for the
adaptation On the one hand, the inserts may be stored for study of
the recreation of the patient itself with time and/or may be stored
for later comparison with the recreation of other patients.
[0026] Consequently, an embodiment of the invention also comprises
an insole adjustment kit, wherein the cover foil is provided with
information about the corresponding insert, for example, the shoe
size related to the insert the insert thickness, information about
the material of the insert, and/or information indicating the
elasticity of the insert.
SHORT DESCRIPTION OF THE DRAWINGS
[0027] The invention will be explained in more detail with
reference to the drawing, where
[0028] FIG. 1 illustrates an insole according to the invention, a)
is a cross section and b) is a view from the underside,
[0029] FIG. 2a)-d) shows different inserts,
[0030] FIG. 3 illustrates an insole with a laterally small insert
above a large insert, a) is a cross section and b) is a view from
the underside
[0031] FIG. 4 illustrates an insole with pockets of different
heights, a) is a cross sectional view of a first embodiment b) is a
view from the underside, and c) is a cross section of a further
embodiment,
[0032] FIG. 5 illustrates an insole with an insert under the middle
of the foot,
[0033] FIG. 6 shows an insert with cover foil,
[0034] FIG. 7a-c) illustrates marking of the insert for
adaptation,
[0035] FIG. 8 shows a patient journal with cover foils for
recording.
DETAILED DESCRIPTION/PREFERRED EMBODIMENT
[0036] FIG. 1a is a cross sectional view of an insole from a kit
according to the invention. The upper layer 101, for example
suitably made of polymer foam, has a first pocket 102 and a second
pocket 103 between the upper layer 101 and a lower, liquid filled
layer 107. The liquid filled layer may be made of two plastic
sheets welded at the borders to provide a closed cavity filled with
liquid, typically water.
[0037] The pockets 102 and 103 are provided as recesses in the
upper layer 101. Inside the pocket 102 under the heel area, an
insert 104 has been provided. In the pocket 103 under the forefoot,
an insert 105 has been provided which has a perforation 106 in
order to provide less pressure against the foot sole than the area
surrounding the perforation 106.
[0038] As it appears in greater detail in FIG. 1b, the lower,
liquid filled layer 107 is situated between fixation elements 108
and 109 in order to prevent that the lower layer 107 slides
relatively to the upper layer 101. After insertion of the inserts
104, 105, the lower layer may be glued on the inserts 104, 105 and
the upper layer 101 in order to achieve a proper final fixation
ready for use.
[0039] FIG. 2 illustrates a number of different inserts 105. The
first insert in FIG. 2a has a perforation 106 for pressure
reduction against the foot sole in the area of the perforation 106.
In order to reduce the pressure against the foot sole even further,
a hole 201 through the insert may be provided. In a further
development, a combination of holes and perforation pattern may be
provided, for example as illustrated in FIG. 2c with a perforation
203 surrounding a larger hole 202. In FIG. 2d, a likewise
arrangement of an insert 105 with a hole 205 and a perforation 206
surrounding the hole is illustrated. However, in this case, the
perforation 206 and the hole 205 are provided in an area, where the
insert 105 has a region 204 with a softer material than the
remaining part of the insert. These drawings illustrate the
multiple possibilities in adjustment of an insole for a diabetic
patient by a simple kit according to the invention.
[0040] FIG. 3 illustrates an insole, where the heel insert 104 and
the forefoot insert 105 are each provided with a hole 303 and 301,
respectively. Under the first insert 105, a second insert 302 is
provided, where the lateral dimension of the second insert is
smaller than the lateral dimension of the first insert, the first
insert 105 having a lateral extension corresponding to the lateral
extension of the pocket 103. The smaller, second insert 302 is a
thin, flexible and relatively hard plate for distributing pressure
from the upper, softer insert 105 over a larger area on the liquid
filled, lower layer 107.
[0041] FIG. 4 illustrates an insole with an upper layer 401, in
which the recess 403 in the forefoot region is deeper than the
recess 402 in the heel region. Among the inserts 404 and 405, only
the insert 405 in the forefoot, as illustrated in FIG. 4a and 4b is
provided with a hole 406. In addition, a small, pressure
distributing plate 407 is provided in the pocket 401, the pressure
distributing plate 407 having a lateral dimension larger than the
lateral extension of the hole 406.
[0042] In FIG. 4c, the recess 403 in the forefoot region is filled
with two inserts 408 and 410, each insert having a hole 409, 411,
where the hole in the upper insert is smaller than the hole in the
loser insert resulting in a gradual pressure on the foot sole
around the hole. In addition, the hardness of the two inserts 408
and 410 may be different.
[0043] As it appears from the foregoing, a kit for an insole
according to the invention provides an advantageous system with
many degrees of freedom, yet easily and quickly adjusted. The
benefit for the patient is an almost immediate relief, whereas the
benefit for the society is reduced costs for treatment at a later
stage, where medication and surgery is necessary if the potential
damages are not prevented by immediate action at an early
stage.
[0044] For heavy weight people, there is a substantial risk that
the feet sink down and thereby gets flat-footed. The reason is not
well established, but it is believed that reduced blood circulation
has influence on this phenomenon. In this case, it may be relevant
to use an insert 501 under the middle part of the foot, which is
illustrated in FIG. 5, showing an insole 500 formed after the flat
foot of an overweight person. In the figure, three inserts 501, 502
and 503 are illustrated, each insert adapted to the needs and
cushioning effect desired for the specific person. The inserts 501,
502, 503 may be provided with different perforations or holes in
accordance with the needs of the patient and as explained in the
foregoing in connection with inserts.
[0045] Inserts may be inserted into the upper, cushioning insole
from the underside of the upper cushioning insole. However, if a
more flexible solution is desired, there may be provided access to
the pockets from the side of the upper part. For example, there may
be provided access to the front pocket under the forefoot from the
font of the insole. Likewise, there may be provided access to a
heel pocket from the back of the insole or from the side of the
insole. For the middle insert, there may be provided access from
the side of the insole.
[0046] During assembly of an insole from an insole kit according to
the invention, the inserts may be placed directly in the pockets
with access from the underside of the upper part. Then, the lower,
liquid filled part is glued, welded, or otherwise fastened to the
upper part of the insole. By using accesses to the pockets from the
sides, inserts may be exchanged on demand even after assembly of
the insole. For example, the combination of a plurality of inserts
in one pocket may be amended during change of conditions for the
foot, for example during healing, which makes the kit according to
the invention even more flexible.
[0047] As an example and as illustrated in FIG. 6, the inserts 105
may be provided with glue 601 on the upper side in order to be
fastened to the upper layer. Initially, this glue may be covered by
a removable foil 602, such as silicone paper.
[0048] In order to provide a perforation 106 or a through going
hole 201 for reduction of pressure against the foot sole, the
following procedure may be applied as illustrated in FIG. 7a. The
inserts 104 and 105 may be placed in recesses of the upper layer
101 of the insole for the opposite foot in other words, an insert
for the right foot is placed in the upper layer of the left insole
and vice versa. The insole is then placed upside down such that the
upper layer 101 is resting on the floor and the foil covered insert
is facing with the foil 602 upwards. The foot sole 702 of the foot
701 of the patient is placed on top of the foil 602, as illustrated
in FIG. 7b, and the location of the sore 703 and for a perforation
106 or hole 201 is marked 704 with a pen on the foil 602 of the
insert 105 in the upside down placed insole 101, which is
illustrated in FIG. 7c. Alternatively, ink is put on the sore 703
on the foot sole 702 for transfer as a spot 704 to the cover foil
602 on contact between the foot sole and the cover foil. In this
case, the surface of the cover foil may be configured such that it
is easy to transfer ink from the foot to the cover foil. Thus, the
cover foil 602 for the insert is provided with information about
the adaptation of the insole.
[0049] After marking, the insert 602 is taken out of the upper
layer 101 and placed in the corresponding other upper layer 101 for
correct use which is not in an upside down orientation. Before
insertion in the pockets of the correct upper layer, the insert may
be subject to further adaptation and/or combination with other
inserts.
[0050] FIG. 8 illustrates a patient journal 801. The journal 801
comprises patient details 802 and areas 803 dedicated to cover
foils 602 released from the insert and placed in the journal 801
and having information about the position of the sore and
corresponding perforation 106 or hole 201, which may then be used
for documentation in a medical or orthopaedic journal of the
patient in order to minimise possible mistakes in the journal, in
as much as the cover foils are direct documentation for the
adaptation. The cover foils 602 may contain further information,
for example material and flexibility of the insert and shoe size of
the insole.
* * * * *