U.S. patent application number 10/136770 was filed with the patent office on 2002-11-07 for unitary orthotic insert and orthopedic insole.
Invention is credited to Campbell, Todd Duncan, Davis, Russell Craig, Guthrie, William Yeager.
Application Number | 20020162250 10/136770 |
Document ID | / |
Family ID | 26834621 |
Filed Date | 2002-11-07 |
United States Patent
Application |
20020162250 |
Kind Code |
A1 |
Campbell, Todd Duncan ; et
al. |
November 7, 2002 |
Unitary orthotic insert and orthopedic insole
Abstract
The invention provides a unitary orthotic insert for a shoe that
comprises a cupped heel portion having a concave upper bearing
surface and a midfoot portion having a medial longitudinal arch
support with a curvilinear upper bearing surface. The cupped heel
portion extends above a most posterior cephalad portion of a
calcaneus and is continuously coupled to the midfoot portion.
Inventors: |
Campbell, Todd Duncan;
(Petaluma, CA) ; Davis, Russell Craig; (Greenbrae,
CA) ; Guthrie, William Yeager; (Fairfax, CA) |
Correspondence
Address: |
JOHNSON & STAINBROOK, LLP
3550 Round Barn Blvd., Suite 203
Santa Rosa
CA
95403
US
|
Family ID: |
26834621 |
Appl. No.: |
10/136770 |
Filed: |
April 30, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60288319 |
May 2, 2001 |
|
|
|
Current U.S.
Class: |
36/166 ; 12/146M;
36/173; 36/180 |
Current CPC
Class: |
A43B 7/142 20130101;
A43B 7/226 20130101; A43B 7/141 20130101; A43B 23/17 20130101 |
Class at
Publication: |
36/166 ; 36/173;
36/180; 12/146.00M |
International
Class: |
A43B 007/14 |
Claims
What is claimed as invention is:
1. A unitary orthotic insert for a shoe comprising: a cupped heel
portion having a concave upper bearing surface; and a midfoot
portion having a medial longitudinal arch support with a
curvilinear upper bearing surface; wherein the cupped heel portion
extends above a most posterior cephalad portion of a calcaneus and
is continuously coupled to the midfoot portion.
2. The unitary orthotic insert of claim 1 wherein the cupped heel
portion and the midfoot portion cooperate to invert a subtalor
joint of a foot to a position of inversion to lock a midtarsal
joint during ambulation of a foot to reduce pronation and provide
stabilization.
3. The unitary orthotic insert of claim 1 wherein the concave upper
bearing surface of the cupped heel portion comprises a heel cup
angle of at least 90 degrees.
4. The unitary orthotic insert of claim 1 wherein the midfoot
portion extends from the cupped heel portion to an opposite end
corresponding to an anterior end of a metatarsal bone.
5. The unitary orthotic insert of claim 1 wherein the cupped heel
portion and the midfoot portion cooperate to provide a therapeutic
characteristic for a podiatric condition.
6. The unitary orthotic insert of claim 5 wherein the podiatric
condition includes plantar fasciitis.
7. The unitary orthotic insert of claim 5 wherein the podiatric
condition is selected from the group consisting of cuboid syndrome,
a neuroma, hammertoe, a bunion, a pronation condition, tendonitis,
and a foot ailment.
8. The unitary orthotic insert of claim 1 further comprising: a
lower bearing surface substantially conforming to an inside surface
of a shoe.
9. The unitary orthotic insert of claim 1 wherein the cupped heel
portion and the midfoot portion are formed from a flexible
material.
10. The unitary orthotic insert of claim 9 wherein the flexible
material is selected from the group consisting of a neoprene
rubber, a silicone rubber, an elastomer, a polymeric material, a
urethane, polyethylene teraphthalate, a viscoelastic material, a
silicone gel, and combinations thereof.
11. The unitary orthotic insert of claim 9 wherein the flexible
material comprises a gripping characteristic to provide proximal,
posterior and lateral support when engaged with the heel bone.
12. The unitary orthotic insert of claim 1 further comprising: a
texture embossed on the upper bearing surface.
13. The unitary orthotic insert of claim 1 further comprising: an
absorptive layer disposed on at least a portion of the upper
bearing surface.
14. The unitary orthotic insert of claim 1 further comprising: a
forefoot portion having a substantially planar upper bearing
surface, wherein the forefoot portion is continuously coupled to
the midfoot portion and extends from the midfoot portion to a
region corresponding with a distal end of the foot.
15. The unitary orthotic insert of claim 1 further comprising: a
reinforcing support member built into the unitary orthotic
insert.
16. A specialty shoe comprising a unitary orthopedic insole,
wherein the unitary orthopedic insole comprises a cupped heel
portion having a concave upper bearing surface that extends above a
most posterior cephalad portion of a calcaneus, a midfoot portion
with a curvilinear upper bearing surface having a medial
longitudinal arch support, and a forefoot portion having a
substantially planar upper bearing surface.
17. The specialty shoe of claim 16, wherein the specialty shoe is
selected from the group consisting of an athletic shoe, a running
shoe, a tennis shoe, a cross-trainer shoe, a children's shoe, a
work shoe, a dress shoe, a casual shoe, an open-toe shoe, an
orthopedic shoe, a sandal, a military shoe, an all-terrain shoe, a
diabetic shoe, a maternity shoe, and a boot.
18. The specialty shoe of claim 16, wherein the unitary orthopedic
insole is integrated into the innersole of the specialty shoe.
19. A method of manufacturing a unitary orthotic insert for a shoe
comprising: providing a unitary orthotic insert mold with a cavity
for a cupped heel portion having an upper bearing surface, a
midfoot portion having a medial longitudinal arch support with a
curvilinear upper bearing surface; injecting an injection-molding
compound into the unitary orthotic insert mold; and releasing the
unitary orthotic insert from the unitary orthotic insert mold.
20. The method of claim 19 wherein the injection-molding compound
is selected from the group consisting of a neoprene rubber, a
silicone rubber, an elastomer, a polymeric material, a urethane,
polyethylene teraphthalate, a viscoelastic material, a silicone
gel, and combinations thereof.
21. The method of claim 19 further comprising: providing a
pre-molded support member; and inserting the pre-molded support
member into the unitary orthotic insert mold prior to injecting the
injection-molding compound.
22. The method of claim 19 further comprising: attaching an
absorptive layer on at least a portion of the upper bearing
surface.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of the filing
date of U.S. Provisional Patent Application Serial No. 60/288,319,
filed May 2, 2001.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
TECHNICAL FIELD
[0004] The present invention relates generally to orthopedic
devices, and more particularly to an orthotic insert and an
orthopedic insole for a shoe to abate and prevent foot and related
ailments.
BACKGROUND INFORMATION AND DISCUSSION OF RELATED ART
[0005] Custom orthotics for feet typically contain a relatively
rigid, resilient base comprising a heel portion and an arch
portion, contoured to fit the plantar or bottom surface of the
foot. Orthotic devices may be inserted into footwear to reduce
pronation of feet and to provide a therapeutic and corrective
effect for foot ailments such as plantar fasciitis, cuboid syndrome
and tissue trauma. Custom-made orthotics are generally created from
hard plastics by using a mold or extensive measurements of an
individual's foot, and modified as needed to provide prescribed
corrections by a podiatrist. Unfortunately, custom orthotics
typically fit into only one or a few pairs of shoes, and are too
expensive for a wide variety of shoes that might be part of a
person's wardrobe. Because of the expense, orthotic devices are
often used only after serious degradations of a foot problem and
severe increase in foot pain. As a foot condition improves,
prescribed orthotics may require alterations with less correction
or be discarded altogether. Although highly beneficial in
correcting early onsets of podiatric conditions, custom orthotics
for a child may be considered cost prohibitive, with frequent size
alternations needed due to rapid growth of the feet and changing
body physiology of the child.
[0006] In contrast to custom orthotics, inexpensive shoe inserts,
which often comprise relatively thin layers of foam material, can
be removed from shoes so that they may be washed, replaced, or used
in other shoes. These inserts may provide some additional comfort,
albeit with temporary relief and minimal physiological effect.
[0007] A conventional insole often consists of materials such as
elastomeric foam that are covered with and adhesively bonded to
leather, natural fabrics or other synthetic materials. The insole
may be contoured to conform to the outline of the foot for
placement atop the sole of a shoe. The insoles generally have a
flat shape cut out of a sheet of material in the shape of the foot,
with additional material in the area corresponding to the arch
portion of the foot, and more material in the region surrounding
the heel of the foot. Many conventional insoles use an impact
cushioning layer or space filler made from synthetic polyurethane
or polyolefin foam that has compression-deformation
characteristics. Thus, when a wearer puts on a shoe having such an
insole, the impact cushion layer of the insole is deformed with the
weight of the wearer and conforms to the shape of the foot. Over
time and with use, these deformations may become permanent,
forfeiting the initial comfort and impact-absorbing qualities of
the insole.
[0008] While commonly used, conventional insoles are often
ineffective in preventing or alleviating pain associated with foot
conditions such as plantar fasciitis. The top surface of their
contoured foam material are designed to support and cradle the
foot, but the foam is intended mainly to cushion the foot and not
to provide the necessary support for proper biomechanical functions
of the foot, particularly in the rearfoot and arch areas.
Non-custom accommodative orthotics tend to be fabricated from a
soft material that compresses under loads, so as to be tolerated by
a wide variety and shapes of feet. While increasing foot comfort,
they are unlikely to provide significant control of foot
motion.
[0009] Some over-the-counter insoles provide limited support in the
heel and rear foot areas, but do little to prevent excessive foot
pronation. Pronation is an inwardly declining complex motion of the
calcaneus or heel bone involving a partial collapse of the medial
longitudinal arch of the foot. It occurs during ambulation, after
an initial heel strike as the weight and movement of the body
progresses forward onto the balls of the feet.
[0010] Some recent efforts have been made to correct foot problems
with firmer and higher durometer materials added to the arch area
and around the heel of the foot. These devices, most of them
custom-molded for the foot, are designed to resist pronation and to
distribute weight-bearing stresses to areas of the foot that can
better tolerate such stresses, thus maximizing comfort and
minimizing trauma to the sole of the foot. Such an orthotic device
may provide a padded surface that is shaped to conform to the
contours of a particular foot. A corrective orthotic may be
designed to guide and restrict the motion of joints of the foot in
order to improve gait efficiency and to reduce the stresses imposed
on lower extremity anatomical structures during walking, running
and standing.
[0011] An exemplary and painful foot condition for which orthotic
devices are often used is plantar fasciitis. Extended flattening or
stretching of the plantar fascia, and secondarily from microscopic
tears and tissue irritation resulting from such flattening or
stretching primarily cause plantar fasciitis. Its etiology may
include a traumatic event or sustained trauma from ambulatory
actions, or it may be due to very mild congenital foot
malformations such as flat feet or high arches. Plantar fasciitis
is an inflammation of the plantar fascia, which encapsulates
muscles in the bottom of the foot and supports the arch of the foot
by acting as a bowstring that connects the balls of the foot to the
heel. The plantar fascia endures tensional forces that are
approximately twice the body weight during walking at the moment
when the heel of the trailing leg begins to lift off the ground.
This moment of maximum tension is increased and intensified
suddenly, particularly when there is lack of flexibility in the
calf muscles. A percentage increase in body weight causes the same
percentage increase in tension in the fascia. Due to the repetitive
nature of walking, plantar fasciitis may be a repetitive stress
disorder (RSD) not unlike carpal tunnel syndrome and tennis elbow.
All three conditions benefit greatly from rest, ice, and periodic
stretching, but may also be treated with non-steroidal
anti-inflammation pills (NSAIDs), mechanical splints or straps, and
as a last resort, surgery. Other biomechanical and other
non-surgical methods for treating plantar fasciitis include
injecting steroids, limiting heel strikes, and using heel cups,
cushioned inserts, shock-absorbing athletic shoes, crepe-soled
shoes, aspirin, a short leg walking cast, heat, ultrasonic
treatment and custom orthotics. These treatments and their
effectiveness remain unpredictable, sometimes requiring years for
foot problems to abate.
[0012] Another treatment for plantar fasciitis, as well as other
related foot conditions, is the taping of a foot so as to reduce
subtalar joint motion and thereby restrict pronation. This may
provide immediate pain relief and the reduction of irritation so
that a person may better tolerate a brief period of time while
customized orthotic devices are shaped and delivered. However,
taping requires a considerable investment in time and requires the
expertise of an orthopedist, therapist or trainer specifically
skilled in the art. Additionally, taping provides relief and
therapeutic efficacy for only a few days, as the tape invariably
loosens. Taping may impact normal activities, such as bathing or
the selection of footwear. Accordingly, it would be desirable to
provide an effective orthopedic device without the need for taping
or any other time-consuming task.
[0013] Conditions that may benefit from similar orthopedic devices
to those used for plantar fasciitis are arthritis, heel bone
damage, bone spurs, stress fractures, loss of natural tissue for
cushioning under the heel ("fat pad atrophy"), tarsal tunnel
syndrome (the foot's version of carpal tunnel syndrome), stress
fractures, and tendonitis.
[0014] Many people may benefit from non-custom orthotic devices and
not require expensive, individually fabricated orthotic devices. A
desirable orthopedic device, which provides an alternative to some
custom orthotics prescribed by medical specialists, cooperatively
redistributes the normally greater weight-generated forces applied
to the inner and more bony regions of the heel outwardly toward the
outer and more fleshy regions of the heel. Additionally, it would
provide support and stablility to affected areas of the foot and
reduce subtalar joint motion without substantially affecting the
fit of the shoe into which the devices is placed. The beneficial
orthotic device would also have an ability to adjust for variations
in gait, foot and shoe size without the need for a custom fit. In
this respect, the adaptability of the devices may lower the expense
and limit the need for medical assistance in fitting and
prescribing the devices.
[0015] Furthermore, podiatrists and other medical practitioners
would benefit from being able to provide effective noncustom
orthotic inserts for their patients to use in their shoes while
they wait the usual several weeks to receive custom-built
orthotics. These specialists also would be able to provide a line
of shoes with a built-in orthopedic insole that allows the patient
to select from immediately available, off-the-shelf shoes offering
therapeutic properties.
[0016] A desirable orthotic device is adaptable to many types and
sizes of adult and children's shoes, for use as removable inserts
or integrated into the insole or secured onto the sole of a shoe.
To maximize its potential, only a single or small set of orthotic
inserts is required to fit and be useful in a variety of work,
sport, dress, and higher-heeled shoes that a person might wear.
[0017] While orthotic devices are generally considered to be
therapeutic and restorative, this beneficial foot orthotic could
help prevent foot problems caused by pronation, excessive motion of
joints, and increased stresses on vulnerable areas of a foot.
Additionally, it could become integrally incorporated into
well-constructed shoes available to the general public.
[0018] Therefore, an object of this invention is to provide an
orthotic insert for a shoe that overcomes the deficiencies and
obstacles described above. Another object of this invention is to
provide an orthopedic insole that may be built into the inner sole
of a specialty shoe. Yet another object of this invention is to
provide a method of manufacturing an orthotic insert or orthopedic
insole for a shoe that provides preventative and curative
properties for a variety of foot ailments.
BRIEF SUMMARY OF THE INVENTION
[0019] One aspect of the invention provides a unitary orthotic
insert for a shoe comprising a cupped heel portion having a concave
upper bearing surface, and a midfoot portion having a medial
longitudinal arch support with a curvilinear upper bearing surface.
The cupped heel portion extends above a most posterior cephalad
portion of a calcaneus and is continuously coupled to the midfoot
portion. The cupped heel portion and the midfoot portion cooperate
to invert a subtalor joint of a foot to a position of inversion to
lock a midtarsal joint during ambulation of a foot to reduce
pronation and provide stabilization.
[0020] The unitary orthotic insert may include a lower bearing
surface substantially conforming to an inside surface of a shoe.
The unitary orthotic insert may include a texture embossed on the
upper bearing surface. The unitary orthotic insert may include an
absorptive layer disposed on at least a portion of the upper
bearing surface. The unitary orthotic insert may include a forefoot
portion having a substantially planar upper bearing surface. The
forefoot portion may be continuously coupled to the midfoot portion
and may extend from the midfoot portion to a region corresponding
with a distal end of the foot. The unitary orthotic insert may
include a reinforcing support member built into the unitary
orthotic insert.
[0021] Another aspect of the invention is a specialty shoe
including a unitary orthopedic insole, wherein the unitary
orthopedic insole comprises a cupped heel portion having a concave
upper bearing surface that extends above a most posterior cephalad
portion of a calcaneus, a midfoot portion with a curvilinear upper
bearing surface having a medial longitudinal arch support, and a
forefoot portion having a substantially planar upper bearing
surface. The unitary orthopedic insole may be integrated into the
innersole of the specialty shoe.
[0022] Another aspect of the invention is a method of manufacturing
a unitary orthotic insert or orthopedic insole for a shoe.
[0023] The aforementioned, and other features and advantages of the
invention will become further apparent from the following detailed
description of the presently preferred embodiments, read in
conjunction with the accompanying drawings. The detailed
description and drawings are merely illustrative of the invention
rather than limiting, the scope of the invention being defined by
the appended claims and equivalents thereof.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0024] The following drawings are shown with left feet, left
unitary inserts and insoles, and left shoes, and it should be
understood that the right foot, inserts or shoes are substantially
mirror images of the left side. It should also be understood that
the use of the word shoe, in the context of this document, is
intended to be synonymous with nearly all articles of footwear,
including but not limited to boots, sandals, open-toe shoes and
closed-toe shoes. Further characteristics and advantages of the
invention will become apparent from the following detailed
descriptions of particular but not exclusive embodiments,
illustrated by way of non-limitative examples in the accompanying
drawings, wherein:
[0025] FIG. 1 illustrates a side view and a top view of a human
foot;
[0026] FIG. 2 illustrates a perspective view of a unitary orthotic
insert, in accordance with the current invention;
[0027] FIG. 3 illustrates a top view of a unitary orthotic insert,
in accordance with the current invention;
[0028] FIG. 4 illustrates a side view of a unitary orthotic insert,
in accordance with the current invention;
[0029] FIG. 5 illustrates a perspective view of a two-thirds or
partial length unitary orthotic insert extending from the heel to
the balls of a foot, in accordance with the current invention;
[0030] FIG. 6 illustrates a top view of a two-thirds or partial
length unitary orthotic insert extending from the heel to the balls
of a foot, in accordance with the current invention;
[0031] FIG. 7 illustrates a cross-sectional view of a unitary
orthotic insert with an absorptive layer on an upper surface, in
accordance with the current invention;
[0032] FIG. 8 illustrates a perspective view of an inside of a
unitary orthotic insert, in accordance with the current
invention;
[0033] FIG. 9 illustrates a perspective view of a shoe with a
full-length unitary orthopedic insole, in accordance with the
current invention;
[0034] FIG. 10 illustrates a perspective view of a shoe having a
unitary orthopedic insole of partial or two-thirds length, in
accordance with the current invention;
[0035] FIG. 11 illustrates a side view of a boot with a full-length
unitary orthopedic insole, in accordance with the current
invention; and
[0036] FIG. 12 illustrates a flow diagram of a method of
manufacturing a unitary orthotic insert or unitary orthopedic
insole, in accordance with the current invention.
DETAILED DESCRIPTION OF THE INVENTION
[0037] The unitary orthotic shoe insert and orthopedic insole of
the present invention may benefit the fitness of the foot by
reducing subtalar joint motion, limiting the stretching of the
plantar fascia and stabilizing the heel of the foot while walking
or running. The present invention may assist in inverting the
subtalar joint to a position of inversion and simultaneously,
plantar-flexing the first ray to lock the midtarsal joint during
ambulation. Thus, the present invention reduces excessive
pronation, a condition that often leads to foot injury. The
therapeutic device is capable of relieving foot pain and
biomechanically correcting or alleviating misaligned conditions in
a foot. The insert may help prevent or provide relief from common
foot problems such as heel spurs, arch pain, metatarsalgia
(ball-of-foot pain), bunions, hammertoe, arthritis, neuromas,
diabetes foot, plantar fasciitis, cuboid syndrome, tendonitis,
stress fractures, shin splints, and other ailments of the foot,
leg, and lower back. Diabetics, for example, may be more
susceptible to foot disease such as ulcers or sores caused by
infection and minor injuries that may be avoided or corrected by
use of an effective insert. Although the invention may serve as an
aid in the recovery from a foot ailment, the invention may also
serve to prevent the onset or reoccurrence of various foot problems
and athletic injuries.
[0038] The insert includes a high-rise heel cup portion that
absorbs shock during heel strikes, while providing support to the
proximal, distal and posterior of the calcaneus. The insert
includes a midfoot portion that cooperates with the heel portion to
stabilize and support the foot while preventing excessive
pronation, and provides a therapeutic characteristic for a
podiatric condition.
[0039] The deep heel cup portion of the present invention wraps
around the heel of the foot and extends above a most posterior
cephalad portion of a calcaneus, which is the area above the
posterior portion of the heel bone proximal to the Achilles tendon.
The midfoot portion of the insert is continuously coupled to the
cupped heel portion. The midfoot portion includes a curvilinear
upper bearing surface and a medial longitudinal arch support to aid
in the support of the medial longitudinal arch of the foot. The
upper surface of the midfoot portion may include a minor arch to
support the lateral longitudinal arch near the outside of the foot,
and a minor arch to support the transverse arch perpendicular to
the medial longitudinal arch and the lateral longitudinal arch of
the foot. The midfoot portion extends from the heel cup towards the
heads or anterior ends of the metatarsal bones.
[0040] The single piece or unitary orthotic insert may also include
a forefoot portion that is a generally flat or planar section
continuously coupled to the midfoot portion, and contoured around
the perimeter to correspond with the sides and distal end of a
person's foot.
[0041] The cupped heel portion and the midfoot portion coordinate
to help realign the rearfoot to avoid overpronation and reduce
stress on the Achilles tendon. Excessive pronation renders the gait
of a walker or runner less efficient, and is a source of lower
extremity pathologies, including muscle tiredness and inflammation,
foot and knee joint pain, tendonitis, ligament strain, and even
neurological damage. With the full-length insert or insole, the
forefoot portion may cushion and reduce stress on the balls and
phalangeal area of the foot.
[0042] The present invention may be a removable insert for a shoe
or may be an insole integrated into the innersole of a shoe. The
actual dimensions of a unitary orthotic insole and insole, in
accordance with the present invention, will vary depending on the
size of the foot, the intended use of the shoe, and other factors.
The net result of various embodiments of the present invention is a
unitary orthotic insert that controls pronation, supports the foot,
and produces a more stable platform on which and in which the foot
ambulates.
[0043] FIG. 1 illustrates a side view and a top view of a human
foot at 100. The toes of a human foot are formed by fourteen
phalanges. Starting from the inside of the foot, each toe has
distal phalanges 102, 104, 106, 108 and 110, middle phalanges 114,
116, 118 and 120, and proximal phalanges 122, 124, 126, 128 and
130. The first phalange or big toe lacks a middle phalange. The
forefoot comprises the phalanges and the heads or anterior end of
the metatarsals.
[0044] The midfoot includes five metatarsals 132, 134, 136, 138 and
140. First metatarsal 132, which is the shortest and thickest of
the metatarsal bones, bears the most weight and plays the most
important role in propulsion. First metatarsal 132 also provides
attachment for several tendons. The more stable second metatarsal
134, third metatarsal 136, and fourth metatarsal 138 are well
protected with only minor tendon attachments, and thus are not
subjected to strong to pulling forces.
[0045] The midfoot also includes five of seven tarsal bones:
navicular, cuboid, and cuneiform bones. The distal row contains
three cuneiforms 142, 144 and 146 and a cuboid 148. The midfoot
includes five tarsometatarsal joints, which are among multiple
joints within the midfoot itself. Proximally, cuneiforms 142, 144
and 146 articulate with a navicular 150.
[0046] A talus 152 and a calcaneus 154 make up the rear or hind
portion of the foot. Calcaneus 154 is the largest tarsal bone, and
forms the heel. Talus 152 rests on top of it, and forms the pivot
for the ankle.
[0047] Toe movements take place at joints that are capable of
motion in two directions: plantar flexion and dorsiflexion, as well
as abduction and adduction. The remainder of the foot has two
movements, inversion and eversion, to which joints of the hindfoot
and midfoot contribute. These complex movements are combined
ordinarily with ankle movements and movements of the fibula and
tibia.
[0048] Two primary functions of the foot are weight bearing and
propulsion, both requiring stability and flexibility. The bones and
intervening joints of the foot give flexibility while multiple
bones form an arch to support the weight of the body.
[0049] The three arches of the foot are the medial longitudinal
arch, lateral longitudinal arch, and transverse arch. The inner or
medial longitudinal, the highest of the arches, comprises calcaneus
154, talus 152, navicular 150, cuneiforms 142, 144 and 146, and
first three metatarsals 132, 134 and 136. The outer or lateral
longitudinal arch, which is lower and flatter than the medial arch,
comprises calcaneus 154, talus 152, cuboid 148, and fifth
metatarsal 140. At times, fourth metatarsal 138 is included in the
lateral arch. The generally hemispherical arc of the transverse
arch comprises cuneiforms 142, 144 and 146, cuboid 148, and the
bases of metatarsals 132, 134, 136, 138 and 140. The arches of the
foot are maintained by the shapes of the bones and ligaments, and
supported by muscles and tendons. The lateral arch, medial arch and
transverse arch aid the foot in supporting and distributing the
weight of a person. During a heel strike, for example, the force on
the heel region may exceed three times the normal weight of the
body.
[0050] When walking, body weight is first placed on the heel, then
forward to the ball of the foot. As body weight is applied to the
foot, the arches flatten out slightly to absorb the added pressure,
spreading out the force and strain across the bones of the foot
evenly. As the foot is lifted before taking another step, the arch
springs back into its arched position.
[0051] The foot has two primary motions: supination and pronation.
Supination is a combination of inward rotation at the ankle,
adduction of the hindfoot, inversion of the forefoot, and medial
arch elevation. Supination occurs when a heel comes off the ground.
Subtalar joint supination involves three simultaneous planes of
motion: adduction, inversion, and plantarflexion. As the foot
supinates, lateral structures tighten. Continued supination and
adduction force may rupture portions of lateral collateral
ligaments or avulse these ligaments from their bony attachment
sites on the distal fibula, resulting in an ankle sprain.
[0052] Subtalar joint pronation involves three simultaneous planes
of motion: abduction of a forefoot, eversion of a hindfoot, and
dorsiflexion. Because of the close contiguity of the joints
involved, pronation is accompanied by eversion of the heel and
internal rotation of the leg and hip. In simple terms, pronation is
a motion that occurs when the foot lands on the outside edge and
the inner arch collapses as far as it can to absorb shock.
[0053] Overpronation, the maximum range of motion between pronation
and supination, is often cited as a cause of leg and foot problems
among runners and a contributor to knee, hip and back pain. While
pronation is a normal part of a person's gait, it is understood
that excessive pronation may be the source of many lower extremity
pathologies, including muscle tiredness and inflammation, foot and
knee joint pain, tendonitis, ligament strain, and even neurological
damage. Excessive pronation may render the gait less efficient
since time and effort is wasted in pronating and supinating.
[0054] FIG. 2 illustrates a perspective view of a unitary orthotic
insert, in accordance with the present invention at 200. A unitary
orthotic insert 210 for a shoe may include a cupped heel portion
250 having a concave upper bearing surface 252 and an upwardly
concave shape for engaging the heel of a foot, and an upwardly
arched midfoot portion 230 having a medial longitudinal arch
support with a curvilinear upper bearing surface 232 for engaging
an arch portion of the foot.
[0055] Unitary orthotic insert 210 has midfoot portion 230 formed
continuously with cupped heel portion 250 and forefoot portion 220.
Midfoot portion 230 extends from cupped heel portion 250 to an
opposite end corresponding to the anterior ends of the metatarsal
bones, and from the inner or medial portion to the outer or lateral
side of the foot.
[0056] Cupped heel portion 250 extends above a posterior portion of
a calcaneus or heel bone and be continuously coupled to midfoot
portion 230. Frontal extremities of cupped heel portion 250 may be
positioned somewhat more forwardly on the medial side than on the
lateral side. Cupped heel portion 250 deforms to conform to the
shape of the heel and to provide medial, posterior and lateral
support to the calcaneus. A posterior surface of cupped heel
portion 250 may engage the heel above the heel bone close to the
Achilles tendon. A medial surface and a lateral surface of cupped
heel portion 250 may engage the heel bone below the ankle
malleolus. The upper edge of cupped heel portion 250 may extend
along an arcuate path in a generally descending manner from the
Achilles tendon to midfoot portion 230. Upper bearing surface 252
of cupped heel portion 250 and upper bearing surface 232 of midfoot
portion 230 may be continuously curvilinear, adapted to follow the
contours of the plantar surface of the foot. A raised arch area in
midfoot portion 230 provides support for the arches of the foot
without collapsing under body weight. Upper bearing surface 252 of
cupped heel portion 250 and upper bearing surface 232 of midfoot
portion 230 are contoured to engage the plantar surface of a foot.
Lower bearing surface 254 of cupped heel portion 250 and lower
bearing surface 234 of midfoot portion 230 may be shaped to
substantially conform to an inside surface of a shoe. Similarly,
lower bearing surface 254 of cupped heel portion 250 and lower
bearing surface 234 of midfoot portion 230 may be shaped to
substantially conform to an inside surface of the sole of a shoe
when built into or integrated with the innersole of a shoe.
[0057] Unitary orthotic insert 210 may act simultaneously on the
calcaneus and subtalar of the foot. Cupped heel portion 250 may
help to stabilize and control the motion of the foot, keeping the
heel in its natural state and preventing it from excessively
pronating or rolling inward during walking and running, thereby
properly aligning the foot and providing better shock absorption
and stress distribution.
[0058] Cupped heel portion 250 and midfoot portion 230 may
cooperate to provide a therapeutic characteristic for a podiatric
condition, which may include plantar fasciitis or another medical
condition such as cuboid syndrome, a neuroma, hammertoe, a bunion,
a pronation condition, tendonitis, or a foot ailment. Other
podiatric conditions may include fat pad atrophy, heel spurs,
metatarsalgia, diabetic foot, hyperkeratosis, Morton's neuroma,
plantar pain from arthritis or peak shock load, sore heels, sore
knees, shin splints, Sever's disease, calcaneal apophysitis,
bursitis, achilles tendonitis, and elongated metatarsals.
[0059] Forefoot portion 220 extends from the forward end of midfoot
portion 230 to the end of forefoot portion 220 corresponding to the
metatarsal heads of a wearer's foot, and from a medial side to a
lateral side of the foot. Forefoot portion 220 may have a
relatively thin, substantially planar upper bearing surface.
Forefoot portion 220 is continuously coupled to midfoot portion 230
and extends from the front of midfoot portion 230 to a region
corresponding with the distal end of the foot while comfortably
encompassing the bottoms of the toes. Forefoot portion 120 may
reduce stress on the balls of the foot, and aid in distributing
ambulatory stresses into the front portion of the foot.
[0060] Unitary orthotic insert 210 may be relatively thick in
cupped heel portion 250 under and around the heel of the foot, and
relatively thin and flexible near its upper and lateral edges.
Unitary orthotic insert 210 may be relatively thick at the arched
regions of midfoot portion 230, particularly in the region under
the medial longitudinal arch of the foot, and relatively thin near
the sides. Unitary orthotic insert 210 may be relatively thin and
generally flat or planar in forefoot portion 220. The thickness and
dimensions of various portions or unitary orthotic insert 210 may
be selected to provide suitable support and stability while thin
where possible to maintain low weight and to allow comfortable
incursion of a foot into a shoe fitted with the orthotic insert or
insole. The size of the insert may be selected to accommodate a
number of shoe sizes for men or women. The dimensions of the insert
may be selected to fit snugly into a children's shoe or one of a
variety of adult specialty shoes. Unitary orthotic insert 210 may
have a seamless surface, or may have ribs, contours or cavities to
retain the structural stability while remaining lightweight.
[0061] Material comprising unitary orthotic insert 210 provides
dynamic control as well as static balance. The lower layer of
unitary orthotic insert 210 is made from a flexible material that
can cushion and absorb the shock from heel strike on unitary
orthotic insert 210. Unitary orthotic insert 210 may be formed from
a substantially flexible, resiliently compressible cushioning
material having an upper surface for engaging a plantar surface of
a foot and a bottom surface for engaging a sole of a shoe. Unitary
orthotic insert 210 may be comprised of a semi-rigid, injection
moldable material. The durometer value of the flexible material may
extend from a value less than 20 to a value in excess of 70. The
flexible material may include a neoprene rubber, a silicone rubber,
an elastomer, a polymeric material, a urethane, polyethylene
teraphthalate, a viscoelastic polymer, a silicone gel, and
combinations thereof.
[0062] The flexible and shock-absorbing polymeric material may be a
lightweight and durable thermoplastic such as polyethylene or
cross-linked ethylene vinyl acetate foam, cross-linked
polyethylene, poly(ethylene-vinyl acetate), polyvinyl chloride, an
acrylic, synthetic and natural latex rubbers, block polymer
elastomers, thermoplastic elastomers, polystyrene,
ethylenepropolene rubbers, silicone elastomers, polystyrene,
polyurea or polyurethane, a polyurethane foam, an elastomeric foam,
a non-foam elastomer, and combinations thereof.
[0063] The flexible material may comprise a gripping characteristic
to allow the shoe insert to firmly engage a heel and midfoot.
Unitary orthotic insert 210 may have a texture embossed on the
upper bearing surface to improve the gripping characteristic.
[0064] The material used in the orthotic system of the present
invention may be a compression-resistant, deformable material that
provides shock attenuation and support for the foot without use of
rigid materials such as posting frequently used in custom orthotic
devices. The absence of such rigid materials allows the orthotic
device to be used with a greater variety of shoes.
[0065] In alternative configurations, reinforcing support members
may be built into the unitary orthotic insert. For example, a rim
region of harder material may surround the base of the cupped heel
portion. Reinforcing support members may be built into the cupped
heel portion of the insert to provide additional support of the
calcaneus, using, for example, semi-circular rods of high strength,
resilient material extending around the back and sides of the heel,
or upwards from the base of the cupped heel portion towards the
ankle. Regions of soft, gel-like material may be incorporated into
select regions of the insert, such as directly underneath the fat
pad of the foot where heels may bruise and bone spurs may
occur.
[0066] FIG. 3 illustrates a top view of a unitary orthotic insert,
in accordance with the present invention at 300. In this
embodiment, unitary orthotic insert 310 is configured with a
midfoot portion 330 and a cupped heel portion 350 as a single unit,
closed about the heel, extending from molleolar height, proximally,
and extending in a contoured fashion distally to the plantar
proximal contact surface. The single-piece insert maintains a
subtalor joint in an inverted position, and locks the midtarsal
joint during ambulation of the foot. Flexible cupped heel portion
350 may include relieved or cutout areas. Cupped heel portion 350
may be continuously joined to midfoot portion 330 to support the
calcaneus and permit limited freedom of movement of the heel
relative to the midfoot portion. Cupped heel portion 350, which
includes a lower surface extending longitudinally and continuously
under midfoot portion 330, is adapted to surround the heel and
adjacent portions of a foot. A reinforcing support member may be
built into cupped heel portion 350 to provide additional support of
the sides, back and bottom portions of the heel, yet retain a
cushioning, impact absorbing characteristic under particularly
sensitive portions of the heel or foot.
[0067] FIG. 4 illustrates a cross-sectional view of a unitary
orthotic insert, in accordance with the present invention at 400.
Unitary orthotic insert 410 may comprise a forefoot portion 420,
midfoot portion 430, and cupped heel portion 450 with upper bearing
surfaces 422, 432 and 452, and lower bearing surfaces 424, 434 and
454, respectively. Lower bearing surfaces 424, 434 and 454 may be
contoured to conform to an inside surface of a shoe and may have
some texture, embossed patterns or other indenting or protruding
features, although the surfaces generally are flat and continuous
with respect to one another.
[0068] The rear part of cupped heel portion 450 opens toward
midfoot portion 430, the heel cup being designed and dimensioned
for adapting to the calcaneus. Cupped heel portion 450 may be
continuously curved. An inner arcuate portion 456 and an outer
arcuate portion 458 of cupped heel portion 450 above the calcaneus
may be angled forwardly and upwardly and accorded a heel cup angle
alpha (.alpha.), the heel cup angle alpha being measured by an arc
sweeping from the base of the upwardly concave cupped heel portion
450 to the top of inner arcuate portion 456. Alternatively, heel
cup angle alpha may be measured by an angle corresponding to a line
essentially parallel to lower bearing surface 454 of cupped heel
portion 450 and a line essentially tangential to the top of outer
arcuate portion 458, with a larger heel cup angle corresponding to
a fuller heel cup. The heel cup angle of the currently preferred
embodiment may be greater than 60 degrees, and preferably greater
than 90 degrees.
[0069] A larger heel cup angle provides more support and stability
for the calcaneus, cooperating with midfoot portion 430 to invert
the subtalor joint of a foot to a position of inversion while
walking or running.
[0070] The medial, posterior, and lateral portions of the heel cup
may hold the vertical axis of the calcaneus essentially coaxial
with the axis of the leg. The longitudinal axis of the heel cup and
midfoot portions are oriented toward the fifth metatarsus of the
foot so as to likewise orient the calcaneus. The midfoot portion
has a curvilinear upper bearing surface to support the subtalar.
The upper surface of the unitary orthotic insert is contoured to
engage and cradle the plantar surface of a person's foot, and the
bottom surface may be generally flat and planar, or shaped to
conform to the inner surface of a shoe.
[0071] The heel cup portion permits limited freedom of movement of
the heel relative to the midfoot portion when the insert is worn.
The bottom region of the heel cup may be thicker to absorb the
primary force of a heel strike. Reinforcement support members may
optionally be embedded and secured into the heel cup to provide
additional support for the calcaneus. Regions of softer, pliable
material or detents may be formed in the bottom region of the heel
cup to provide comfort and relief from heel spurs, for example, or
atrophy of the fat pad.
[0072] FIG. 5 illustrates a perspective view of a two-thirds or
partial length unitary orthotic insert extending from the heel to
the balls of a foot, in accordance with the present invention at
500. Partial length unitary orthotic insert 510 includes a cupped
heel portion 550 and a midfoot portion 530. Many of the therapeutic
and preventative aspects of the full-length unitary orthotic insert
are retained in the partial length embodiment. Being shorter,
partial length unitary orthotic insert 510 may more readily be
inserted into and removed from a user's shoe. Partial length
unitary orthotic insert 510 comprises cupped heel portion 550
having a concave upper bearing surface, and a midfoot portion
having a medial longitudinal arch support with a curvilinear upper
bearing surface. The cupped heel portion extends above the back of
the heel bone, and is continuously coupled to the midfoot portion.
Midfoot portion 530 extends from cupped heel portion 550 to an
opposite end corresponding to the heads or anterior ends of the
metatarsal bones. Points near the medial end of midfoot portion 530
may be more forward than points near the lateral end of midfoot
portion 530. The front edge of the partial length insert may be
straight or curvilinear. The thickness of midfoot portion 530 may
diminish to a smooth taper at the front edge. The lower bearing
surface of cupped heel portion 550 and midfoot portion 530 are
essentially flat or may be shaped to substantially conform to an
inside surface of a shoe.
[0073] Cupped heel portion 550 and midfoot portion 530 are formed
from a flexible material, such as neoprene rubber or other
synthetic or naturally occurring material. A texture may be
embossed on the upper or lower bearing surfaces. Ribs, contours or
cavities may be formed in partial length unitary orthotic insert
510 to decrease weight while retaining stability. Reinforcing
support members may be built into the unitary orthotic insert.
Partial length unitary orthotic insert 510 may have an absorptive
layer disposed on at least a portion of the upper bearing surface
to provide shock absorbing and body moisture absorbing
characteristics.
[0074] FIG. 6 illustrates a top view of a two-thirds or partial
length unitary orthotic insert 610 extending from the heel to the
balls of a foot, in accordance with the present invention at 600.
Cupped heel portion 650 and midfoot portion 630 are continuously
connected and adapted to form around and engage the heel of a foot
and to support the arches. Cupped heel portion 650 comprises an
upwardly concave upper bearing surface extending from beneath the
heel to a point above the calcaneus, with a tapered, upper edge
generally descending from the back of the heel near the Achilles
tendon to midfoot portion 630.
[0075] The perimeter of midfoot portion 630 extends from cupped
heel portion 650 along the outer contours of the medial
longitudinal arch of the foot, traversing laterally underneath the
metatarsal bones of the foot, and continuing along the outer
contours of the lateral longitudinal arch of the foot to cupped
heel portion 650.
[0076] The upper bearing surface of midfoot portion 630 is
contoured to support the medial longitudinal arch, the lateral
longitudinal arch, and the transverse arch of the foot. The lower
surface of midfoot portion 630 and cupped heel portion 650 may be
generally flat or shaped to conform to an inside surface of a
shoe.
[0077] FIG. 7 illustrates a cross-sectional view of a unitary
orthotic insert with an absorptive layer on the upper surface, in
accordance with the present invention at 700. The unitary orthotic
insert may include an absorptive layer 712 attached to the upper
bearing surface of unitary orthotic insert 710. Absorptive layer
712 may comprise a compressible polymeric foam with a nominally
thickness of one-sixteenth to one-eighth inch. Absorptive layer 712
may be treated with bacteria and fungus inhibitors to reduce foot
odors. Absorptive layer 712 may include a cloth, polymeric,
synthetic or natural leather top layer that is fixedly superposed
onto the upper surface of absorptive layer 712 so that the
compressible layer interposes the top layer and support layer. The
top layer may wick moisture from the foot and allows unitary
orthotic insert 710 to breathe. Alternatively, the top layer may be
attached directly to the upper bearing surface of the insert
without an intervening compressible layer.
[0078] FIG. 8 illustrates a perspective view of an inside of a
unitary orthotic insert, in accordance with the current invention
at 800. The surfaces of the insert may be smooth, or embellished
with various patterns and textures. The upper or bottom surfaces of
unitary orthotic insert 810 may have a texture characteristic
formed on or in the bearing surfaces. Textured surfaces may aid in
enhancing the gripping capability of the heel cup to effectively
engage the heel and redistribute stresses. Texture surfaces may
enhance contact with the foot or the sole of a shoe. Textured
surfaces such as deep waffle or honeycomb patterns may enhance
shock-absorbing qualities of the insert, or be cosmetic in
nature.
[0079] FIG. 9 illustrates a perspective view of a shoe with a
full-length unitary orthopedic insole, in accordance with the
present invention at 900. The unitary orthopedic insole comprises
all of the features and attributes of the unitary orthotic insert,
though it may be built into or integrated into the innersole or
insole of a shoe and may be non-removable. A unitary orthopedic
insole 910 may include a lower bearing surface substantially
conforming to an inside surface of a unitary orthopedic insole or
sole of a shoe 960, wherein the unitary orthopedic insole comprises
a cupped heel portion having a concave upper bearing surface that
extends above a posterior portion of the heel bone, a midfoot
portion with a curvilinear upper bearing surface having a medial
longitudinal arch support, and a forefoot portion having a
substantially flat or planar upper bearing surface. Although an
athletic shoe is indicated, the unitary orthopedic insole may be
built into nearly any article of footwear.
[0080] Shoe 960 is a specialty shoe such as an athletic shoe, a
running shoe, a tennis shoe, a cross-trainer shoe, a children's
shoe, a work shoe, a dress shoe, a casual shoe, an open-toe shoe,
an orthopedic shoe, a sandal, a military shoe, an all-terrain shoe,
a diabetic shoe, a maternity shoe, and a boot. In the case of an
athletic shoe, soft-sided uppers may be formed of cloth, vinyl, or
other flexible materials that yield outwardly under pressure,
thereby providing little inward buttressing around the insole. In
the case of a boot, the unitary orthopedic insert may be integrated
into the insole of a work boot, a military boot, or a fashion
boot.
[0081] The perimeter surface of unitary orthopedic insole 910 may
be angled to match the inside of the upper where the upper joins
the sole of shoe 960. Unitary orthopedic insole 910 may be
integrated into a conventional insole that may consist of materials
such as synthetic resin foam or elastomer covered with leather,
woven fabrics, unwoven fabrics or other materials adhesively bonded
thereto. Unitary orthopedic insole 910 may be directly attached to
the sole of the shoe.
[0082] FIG. 10 illustrates a side view of a shoe having a unitary
orthopedic insole of partial or two-thirds length, in accordance
with the present invention at 1000. A unitary orthopedic insole of
partial or two-thirds length conforms to the contours of the sole
of a wearer's foot during use, having a perimeter that encompasses
a foot from the heel to a region near the balls of the foot.
[0083] A shoe 1060 may comprise a unitary orthopedic insole 1010,
wherein the unitary orthopedic insole comprises a cupped heel
portion having a concave upper bearing surface that extends above a
posterior portion of a heel bone and a midfoot portion with a
curvilinear upper bearing surface having a medial longitudinal arch
support, the cupped heel portion and the midfoot portion extending
approximately two-thirds of the length of a foot. Unitary
orthopedic insole 1010 may also include a forefoot portion having a
substantially flat upper bearing surface. Unitary orthopedic insole
1010 may conform to an inside surface of shoe 1060. The unitary
orthopedic insole may be integrated into the innersole of a
specialty shoe, or attached directly to the sole of the shoe. The
partial length or full length insole may be readily adapted to
different shoe sizes and types such as work shoes, sport shoes,
shoes with heels and so forth.
[0084] FIG. 11 illustrates a side view of a boot with a full-length
unitary orthopedic insole, in accordance with the present invention
at 1100. In this embodiment, a boot 1160 may be manufactured to
include a unitary orthopedic insole 1110 that has a cupped heel
portion, a midfoot portion, and a forefoot portion. The cup-like
insole includes a body of elastic material having a bottom surface
that has a shape to fit to a bottom member of a boot. As in other
embodiments of the present invention, unitary orthopedic insole
1110 may have a flat portion corresponding to the forefoot, a
midfoot portion extending from the medial side of the foot to the
lateral side of the foot with a generally curvilinear upper bearing
surface to support the arches, and a concave side wall portion
formed continuously therewith, extending rearwards from the midfoot
portion to an area corresponding to the heel of the foot and
extending upwardly to engage the medial, posterior and lateral
sides of the heel. A partial length unitary orthopedic insole may
be built into the boot, comprising the midfoot portion and the
cupped heel portion.
[0085] A partial length or full-length unitary orthopedic insole
1110 may be integrated into the innersole of the boot, or attached
directly to the inside of the sole of the boot.
[0086] FIG. 12 illustrates a flow diagram of a method of
manufacturing a unitary orthotic insert or a unitary orthopedic
insole for a shoe, in accordance with the present invention at
1200. Although the method is directed at manufacturing a unitary
orthotic insert, it is understood that the method equally applies
to the manufacturing of a unitary orthopedic insole.
[0087] Insert or insole manufacturing method 1200 begins by
providing a unitary orthotic insert mold as seen at block 1210. The
mold may have a cavity for a cupped heel portion, a midfoot portion
and optionally a forefoot portion. The cupped heel portion may have
an upwardly concave upper bearing surface, and the midfoot portion
may have a medial longitudinal arch support with a curvilinear
upper bearing surface. The forefoot portion may have a
substantially flat upper bearing surface with the general outline
around the toe or distal end of a foot.
[0088] An injection-molding compound is injected into the unitary
orthotic insert mold, as seen at block 1220. The injection-molding
compound may include a neoprene rubber, a silicone rubber, an
elastomer, a polymeric material, a urethane, polyethylene
teraphthalate, a viscoelastic material, a silicone gel, and any
combination thereof. The compound may be cured or treated to form
the flexible material, as is known in the art. A pre-molded support
member may be provided and inserted into the unitary orthotic
insert mold prior to injecting the injection-molding compound.
[0089] The unitary orthotic insert is released from the unitary
orthotic insert mold, as seen at block 1230. An absorbing material
optionally may be attached to at least a portion of the upper
bearing surface of the unitary orthotic insert, as sent at block
1240. The unitary orthotic insert optionally may be built into the
innersole or onto the sole of a shoe, as seen at block 1250.
[0090] While the embodiments of the invention disclosed herein are
presently considered to be preferred, various changes and
modifications can be made without departing from the spirit and
scope of the invention. The scope of the invention is indicated in
the appended claims, and all changes that come within the meaning
and range of equivalents are intended to be embraced therein.
* * * * *