Note: Descriptions are shown in the official language in which they were submitted.
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DEVICE FOR APPLYING COLD THERAPY TO FEET
SPECIFICATION
FIELD OF INVENTION
The present invention relates to a device for applying cold therapy to feet.
More
particularly, this invention relates to a device for treating ailments and
inflammations of
the foot including plantar fasciitis and tendonitis such as Achilles
tendonitis, by applying
cold therapy to reduce inflammation in these areas of the foot.
BACKGROUND OF THE INVENTION
As feet bear the weight of the body, foot tendons are also susceptible to many
stresses while standing, walking, running, or jumping. If normal motion of the
tendon is
impaired, the tendon will become inflamed and movement will become painful.
This is
called tendonitis, and literally means inflammation of the tendon. Common
causes of
tendon pain are improperly fitting shoes or constant use of high heeled shoes,
improper
movement of the foot, repetitive sports activity or physical activity or
trauma, obesity,
aging, flat feet or feet with very high arches, overuse of tendons, diabetes,
and
rheumatoid arthritis.
Elderly or aged people are mostly affected by foot tendon and ligament pain.
However, tendonitis can also be experienced by younger people in case of
repeated injury
to the tendon because of overuse. Foot tendonitis is commonly found in the
Achilles
tendon at the ankle joint. The Achilles tendon is the thickest and strongest
tendon in the
body. The Achilles tendon connects the heel to the muscles of the lower leg.
Physicians
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routinely prescribe the application of ice packs to reduce pain and swelling
associated
with tendonitis.
The plantar fascia is located in the arch area of the foot and runs across the
bottom
of the foot from the heel to the ball and spreads out across the width of the
foot. The
plantar fascia serves as a shock absorber while walking and transfers tensile
forces along
the bottom of the foot. The plantar fascia serves the vital role of
maintaining the shape of
the arch of the foot. As tensile stresses are produced in the bottom of the
foot, the plantar
fascia absorbs the tensile forces and maintains the shape of the foot arch.
For example, while standing or while in motion, forces experienced by the foot
tend to flatten the arches. This flattening effect is especially acute in
people having high
arches. The plantar fascia running along near the bottom surface of the foot
is analogous
to a string in an archer's bow. Forces that tend to move the ends of the bow
apart
increase tension on the string. In other words, as forces on the arch push the
bones
downward, the plantar fascia is subjected to tensile forces. If the tension on
the plantar
fascia becomes excessive, the plantar fascia may be damaged and produce a
condition
called plantar fasciitis. Plantar fasciitis is a painful medical condition
resulting from
inflammation of the plantar fascia. The plantar fascia is thick and
essentially inelastic.
Overstressing the plantar fascia may produce tears in the plantar fascia or
separate the
plantar fascia from bone and other surrounding materials. Frequently, the
inflamed areas
are along the arch of the foot or near the heel of the foot. Plantar fasciitis
may be quite
debilitating in that everyday activities such as walking and standing may be
very painful.
Ice or other types of cold compresses are commonly recommended by physicians
for reducing inflammation, especially resulting from high impact activities or
from
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standing still for extended periods of time. Typical treatments for tendonitis
of the foot
and plantar fasciitis may involve oral anti-inflammatories, ice packs,
bedrest, stretching,
steroid injections, night splints and wedge-shaped arch supports. In extreme
cases,
treatment of tendonitis of the foot or plantar fasciitis may require
corrective surgery.
For example, treatment for plantar fasciitis may include medical personnel
strapping strips of tape to the bottom of an injured foot. Strips of tape are
applied at
various angles across the bottom of the foot. The tape is difficult to remove
from the
rolls and bunches up during the taping process. Thus, care must be exercised
during the
application of the tape to avoid wrinkles in the tape which can cause blisters
and other
problems. Taping the foot can be cumbersome, inefficient, and ineffective in
preventing
excessive stretching of the plantar fascia. Additionally, applying and/or
attaching an ice
pack to the foot may be cumbersome and may require the use of a bandage or
other
securement means to attach the ice pack to the foot.
Sometimes when current methods of treatment for tendonitis of the foot and
plantar fasciitis are ineffective, expensive surgical procedures are required
to relieve pain.
For example, to obtain access to a tendon of the foot or the plantar fascia,
surgeons may
perform either an endoscopic procedure requiring small incisions or
conventional direct
visualization requiring the underside of the foot to be opened up. With either
painful
procedure, scars may result and recovery time may be from weeks to months.
Even with treatment, improper treatment of tendonitis or plantar fasciitis may
lead
to other medical problems. For example, improper treatment of plantar
fasciiitis can lead
to "heel spurs." Thus, it is desirable to have a device for treating the pain
of tendonitis or
plantar fasciitis. It is also desirable to have a device for treating foot
inflammations such
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as tendonitis of the foot and plantar fasciitis that is economical and may be
easily applied
by the wearer.
SUMMARY OF THE INVENTION
A device for applying cold therapy to the foot of a wearer is disclosed. The
device comprises a foot pad having a premolded configuration for directly
contacting the
bottom of the foot and surrounding heel area. The foot pad includes a heel
portion sized
to receive and surround the heel of the foot. The foot pad also includes a
raised and
contoured arch portion positioned to lie beneath and place localized pressure
on the arch
of the foot where the plantar fascia and tendons of the foot are located. The
entire foot
pad is formed of an ice pack that includes a container or shell for receiving
and
containing a substance capable of maintaining an extremely low temperature for
an
extended period of time during application to the foot. The device also
includes a
securement mechanism that is arranged for engaging the foot pad to the bottom
of the
wearer's foot.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a side elevational view of a preferred embodiment of the present
invention attached to a foot;
Fig. 2 is an isometric view of a preferred embodiment of the present invention
attached to a foot;
Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. 2; and,
Fig. 4 is a cross-sectional view taken along line 4-4 of Fig. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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Referring now to Fig. 1, there is shown at 10 a device of the present
invention for
applying cold therapy to a human foot. The longitudinally-extending foot 14
includes a
heel 18 (Fig. 3), an inner side 22, an outer side 26, and a plurality of five
longitudinally-
extending toes 30 extending from a metatarsal joint located in the ball 34 of
the foot 14.
The foot 14 is connected to an ankle of a leg at the ankle joint 38 disposed
above the heel
18 of the foot 14. As best shown in Fig. 3, the foot 14 includes an arch
(located in the
region indicated at 42) in which the plantar fascia extends. The plantar
fascia is attached
to the heel bone (calcaneus) located generally at 18 and fans out to attach to
the bottom of
the metatarsal bones in the region of the ball 34 of the foot.
The device 10 includes a foot pad 46 that takes the form of a reuseable
freezer
pack that has been molded to approximate the contour of the bottom of a
wearer's foot.
The foot pad 46 shown in the figures is intended for wearing on the left foot.
As best
shown in Figs. 1, 3 and 4, the foot pad 46 is formed of a container defined by
a thin rigid
continuous outer wall 50, the container having an interior cavity for
retaining a coolant or
refrigerant 54 therein. The outer wall 50 may be formed of any suitable
impervious
plastic or rubber material and the container may be formed any suitable
method, e.g.,
blow molding. A suitable plastic might be one that is used for a shell of a
conventional
freezer pack intended for keeping food cold in lunch boxes. The container
includes a
generally flat bottom portion 58 and an in-built upper foot bed 62 that is
contoured to
provide support to the foot 14. The foot pad outer wall 50 is formed of any
suitable
impervious material for containing a coolant or a refrigerant such as a gel or
liquid.
As best shown in Figs. 1 and 3, the foot bed 62 includes a recessed heel cup
portion 66 that provides support for the heel 18. A thickened portion 70 is
provided that
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is integral with the recessed heel cup portion 66 and extends upwardly to make
contact
with the wearer's heel in proximity to the wearer's Achilles' tendon 72. The
upper foot
bed 62 extends forwardly from the heel cup portion 66 through a contoured arch
portion
74 to a front edge 78 located just below the ball 34 of the foot 14. The
contoured arch
portion 74 is shaped to approximate the contour of the wearer's arch in which
the plantar
fascia and tendons of the foot are located. In this manner, the foot pad 46
can apply
localized pressure and cold therapy to the wearer's heel 18, the foot arch
(located in the
region indicated at 42), and through the ball 34 of the foot 14.
The front edge 78 is rounded and contoured to eliminate any sharp edges so the
wearer can comfortably wear the device 10 on the foot with minimal or no
discomfort to
the foot or toes. The device is arranged for wearing while the user is off his
or her feet.
The upper foot bed 62 extends no further than the ball 34 of the foot to
prevent the toes
30 from becoming uncomfortably cold during use of the device 10.
It should be understood that the device 10 of the present invention may be
designed so that the recessed heel cup portion 66 and contoured arch portion
74 of the
upper foot bed 62 are shaped and sized to best suit the contour of the bottom
of a foot
having a high arch, a low arch, or a flat arch. Likewise, the overall
dimensions of the
foot pad 46 may be provided in differing lengths and widths to accommodate
differences
in the length and width of the foot to be treated. As indicated in Fig. 2, the
upper foot
bed 62 includes a sidewall 82 that extends upwardly on the inner side 22 as
well as on the
outer side 26. As best seen in Figs. 1 and 3, as the sidewall 82 extends
rearwardly toward
the heel cup portion 66, it increases in height to surround the heel and form
a well. The
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side wall 82 also provides a means for positioning the foot 14 within the foot
pad 46
during use of the device 10.
One of the most common ways freezer burn or mild frost bite occurs is through
the application of an ice pack to an injury. Referring now to Figs. 3 and 4, a
protective
layer 80 is arranged to lie over the upper foot bed 62 to provide a layer of
protection
between the bottom surface of the foot 14 and the cold surface of the upper
foot bed 62 to
prevent damage to the skin, e.g., freezer burn or mild frost bite, due to
direct contact of
the skin with the cold surface of the upper foot bed 62. The protective layer
80 is
contoured to fit within the sidewall 82 and extends upwardly at the back of
the heel 18 to
provide a layer of protection between the thickened portion 70 and the
wearer's heel in
proximity to the Achilles' tendon 72 to prevent such cold burns in this area.
The
protective layer 80 may be fabricated of a thin fabric material, for example,
a fabric that
is used for covering an insole of a shoe or sneaker.
Prior to use, the device 10 may be placed in a freezer to enable the coolant
or
refrigerant 54 located within the container to solidify. Once the refrigerant
54 has
solidified, the resulting foot pad 46 is cold and rigid. Thereafter, the foot
pad 46 may be
engaged to the bottom surface of the foot in any conventional manner, such as,
by way of
example, straps 90, 94, and 98, with cooperating hook and loop fasteners
(Velcro ) 100
and 104 (Fig. 2). In this manner, the foot pad 46 serves as a rigid cold
compress for
application against the bottom surface of the foot. The foot pad 46 is
contoured to the
shape of the bottom of the foot including the heel, the ball area, and the
arch. In this
manner, cold therapy may be provided to the bottom of the foot to alleviate
pain and
inflammation associated with plantar fasciitis and tendonitis. Likewise, the
thickened
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portion 70 integral with the recessed heel cup portion 66 extends upwardly to
make
contact with the wearer's heel in proximity to the wearer's Achilles' tendon
72 to provide
cold therapy at that location, as Achilles tendonitis often accompanies
plantar fasciitis.
The foot pad 46 may be brought into tight engagement with the bottom surface
of the foot
by suitably tightening the straps 90, 94, and 98, as required. The device 10
is reuseable
in that after therapy has been provided, the device 10 may be returned to the
freezer or
other cooling system to lower its temperature for reuse.
Various alternative coolants or refrigerants 54 may be injected through the
outer
wall 50 of the foot pad 46. The coolant or refrigerant 54 may be inserted into
the foot
pad 46 through a port 108 located in proximity to the rearward thickened
portion 70 of
the recessed heel cup portion 66. The coolants or refrigerants may be non-
toxic, e.g., ice.
Alternatively, gels made of non-toxic materials that will not liquefy, and
therefore will
not spill easily or cause contamination if the foot pad 46 breaks may be
utilized. Such
gels may be made from hydroxyethyl cellulose (Cellusize) or vinyl-coated
silica gel, or
other suitable materials. These gels, as with ice itself, are chilled before
use. The foot
pad 46 is placed in a freezer or other cooling system to lower its
temperature, and then it
may be used to apply cold therapy to regions of the foot where inflammation
occurs such
as the plantar fascia and tendons of the foot including the Achilles tendon.
The coolness
of the foot pad 46 will reduce inflammation and reduce sensations of pain and
tenderness.
While various embodiments have been shown and described, various
modifications and substitutions may be made thereto without departing from the
scope
of the invention described therein.
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