Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DEVICE FOR MITIGATING PLANTAR FASCIITIS
Cross-Reference to Related Applications
[0001] This application claims the benefit of US Patent Application
Number 13/833,981, filed on March 15, 2013, the entirety of which is
incorporated herein by reference.
Background of the Invention
[0002] The present subject matter relates generally to an orthotic
device
that mitigates and treats plantar fasciitis.
[0003] The plantar fascia is a fibrous band within the foot that extends
from the bottom of the heel bone to each of the toes. When a person stands,
the
plantar fascia is stretched under the load of a person's weight, an effect
known as
the "bowstring effect." Once stabilized against the ground, the windlass
action of
a normal plantar fascia will cause the heel to lift and invert. As the
metatarsals
and ankle are dorsiflexed during ambulation, the plantar fascia is stretched
even
further. As such, the plantar fascia is under the greatest tension just as the
heel
lifts off the ground.
[0004] Plantar fasciitis develops when, upon impact, strain, or pressure
on the bottom of the foot, the plantar fascia becomes over-stretched and micro-
tears develop at its attachment to the heel bone. Plantar fasciitis leads to
pain in
the plantar fascia upon weight bearing and pressure applied to the bottom of
the
foot, especially at the point of attachment of the plantar fascia to the heel
bone.
Any activity that causes the plantar fascia to stretch, such as ambulation,
will
aggravate the condition.
[0005] In severe cases of plantar fasciitis, surgery is performed and
requires months of recovery along with prolonged use of custom orthotics to
support the plantar fascia during ambulation. Therefore, early treatment of
plantar fasciitis is desired to avoid surgery.
[0006] Current treatment of plantar fasciitis generally focuses on
reducing stress to the plantar fascia through the use of custom orthotic
devices,
such as custom-made foot arch supports. However, custom-made foot arch
supports fail to provide sufficient support to the plantar fascia during
ambulation because current orthotics do not prevent hyperextension of the
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plantar fascia upon push-off. Further, these orthotics are generally expensive
because each is custom-made to each user's foot profile.
[0007] Footplates, foot braces and orthopedic boots also exist to
decrease
the tension on the connection of the plantar fascia and the heel. However,
these
devices completely immobilize the plantar fascia wherein it becomes stiff and
inflexible. As a result, when the user eventually does apply weight to the
foot, the
healed micro tears in the plantar fascia can be reinjured, thereby forfeiting
any
progress made during recovery. Further, a user's daily activities are
substantially
hindered, if not completely disrupted, by the constrictive, and typically
bulky,
nature and design of the foot braces or orthopedic boots.
[0008] In addition, the rigidity provided by a footplate, foot brace, or
orthopedic boot, may further contribute to an abnormal gait by
overcompensating for the injured plantar fascia and actually worsen the
condition or create additional orthopedic problems elsewhere in the body.
[0009] Accordingly, there is a need for a device to mitigate plantar
fasciitis
by providing the correct balance of support and freedom of movement to reduce
tension in the plantar fascia during ambulation, while at the same time not
completely immobilizing the plantar fascia, as described and claimed herein.
Brief Summary of the Invention
[0010] The present disclosure provides a device and method for
mitigating plantar fasciitis. Various examples of the device and method are
provided herein.
[0011] In an embodiment, a device that reduces tension in a plantar
fascia
during ambulation includes a truss structure, an upper anchor, and an
actuator.
The truss structure includes a posterior portion, a medial portion, a lateral
end,
and a medial end. The upper anchor is proximally located from the truss
structure. The actuator couples the posterior portion of the truss structure
to a
posterior portion of the upper anchor.
[0012] The truss structure may further include at least one stabilizing
element that stabilizes the truss structure to a user's shoe during
ambulation. In
addition, the truss structure may also include at least one securing mechanism
that extends from the lateral portion of the truss structure to the medial
portion
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of the truss structure, wherein the securing mechanism secures the truss
structure to a user's shoe.
[0013] In one example, the securing mechanism includes at least one
dorsal strap that extends dorsally from the lateral portion of the truss
structure
to the medial portion of the truss structure, and at least one ventral strap
that
extends ventrally from the lateral portion of the truss structure to the
medial
portion of the truss structure.
[0014] The truss structure may be configured such that the lateral end
of
the truss structure approximately aligns with a lateral metatarsophalangeal
joint
of a user's foot, and the medial end of the truss structure approximately
aligns
with a medial metatarsophalangeal joint of a user's foot. Having such
alignment,
the truss structure may allow mobility of the metatarsophalangeal joint during
ambulation.
[0015] The truss structure may be attached to the outside of a user's
shoe,
inserted into a user's shoe, or integrated within the structure of a user's
shoe.
[0016] In addition, the truss structure may include a heel support to
further support the plantar fascia during ambulation.
[0017] In one example, the upper anchor is a leg support. The upper
anchor may include a connector element to secure the upper anchor to the
actuator. The upper anchor may be configured to fit around a portion of a
user's
leg, including but not limited to, a user's ankle, calf, knee joint, lower
thigh, or
upper thigh or hip.
[0018] The actuator of the device provides tension to urge heel lift
during
ambulation. The actuator may include non-elastic material, elastic material, a
spring, or combination thereof. The actuator may further include a tension
sensor and/or a tension adjustment mechanism. In additional contemplated
embodiments, the actuator may include an electromechanical actuator.
[0019] In an embodiment, the device includes an upper anchor, an
attachment point, and an actuator. The upper anchor is adapted to be secured
to
a user's leg, for example, at a user's ankle, calf, knee, lower thigh or upper
thigh
or hip. The attachment point is adapted to be secured to the posterior portion
of
the user's heel. The actuator couples the upper anchor to the attachment
point,
wherein the actuator pulls the attachment point towards the upper anchor. The
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attachment point may be integrated into a user's shoe or, alternatively, is a
portion of a truss structure adapted to be secured to a user's shoe.
[0020] The embodiment described above is merely one example and
numerous iterations and variations of the device will be apparent to those
skilled
in the art based on the teachings provided herein.
[0021] The present disclosure also provides for a method of mitigating
plantar fasciitis including providing a device disclosed herein, associating a
truss
structure with a user's shoe, inserting a user's foot into the shoe, and
securing an
upper anchor to the user, and connecting the truss structure to the upper
anchor
through an actuator. The actuator is designed to urge heel lift during
ambulation.
[0022] An advantage of the device provided herein includes protection
against hyperextension of the plantar fascia during ambulation.
[0023] Another advantage of the device provided herein is that the
device
allows the plantar fascia to remain mobile while reducing the risk of renewed
injury to the plantar fascia, thus speeding the recovery process.
[0024] Another advantage of the device provided herein is that the
device
reduces the amount of work done by a user's foot, thereby benefiting a wide
range of users with various foot conditions or whose occupation requires
prolonged standing or walking.
[0025] A further advantage of the device provided herein is that a user
can conveniently use the device in connection with their normal shoe, thus
avoiding the purchase of a therapeutic shoe or boot. In addition, the device
does
not disrupt a user's daily activities, in contrast to a orthopedic boot or
foot brace
that tends to disrupt a user's normal activities.
[0026] Yet another advantage of the device disclosed herein is that the
tension provided by the actuator is adjustable. Therefore, as treatment of the
plantar fasciitis progresses, less and less tension can be used. In other
words, the
device creates a smooth transition towards a point in time when essentially no
tension is used and the user is fully recovered.
[0027] An advantage of the method for mitigating plantar fasciitis
provided herein includes a noninvasive treatment option that does not include
corticosteroid injections, expensive ultrasound therapy, or using devices that
immobilize a user's foot.
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[0028] Another advantage of the method disclosed herein includes a
treatment that reduces the pain associated with plantar fasciitis during
ambulation. Further, the method provided herein allows a user to continue with
daily activities, even in their own shoes.
[0029] Additional objects, advantages and novel features of the examples
will be set forth in part in the description which follows, and in part will
become
apparent to those skilled in the art upon examination of the following
description and the accompanying drawings or may be learned by production or
operation of the examples. The objects and advantages of the concepts may be
realized and attained by means of the methodologies, instrumentalities and
combinations particularly pointed out in the appended claims.
Brief Description of the Drawings
[0030] The drawing figures depict one or more implementations in accord
with the present concepts, by way of example only, not by way of limitations.
In
the figures, like reference numerals refer to the same or similar elements.
[0031] Figs. la-lb are side view perspectives of a force diagram and the
force diagram overlaid on a user's foot, respectively.
[0032] Figs. 2a-2b are a side view and a back view perspective,
respectively, of an embodiment of the device, in operative position with a
user's
foot.
[0033] Fig. 3 is a top view perspective of an embodiment of the truss
structure.
[0034] Fig. 4 is a back view perspective of an embodiment of the device,
in
operative position with a user's shoe.
[0035] Fig. 5 is a side view perspective of an embodiment of the device,
in
operative position with a user's foot.
Detailed Description of the Invention
[0036] Fig. la is a force diagram that depicts a foot truss 10 of a
user's
foot. As depicted in Fig. lb, the heel 12, ankle 14, and metatarsals 16 form
the
truss arch, while the plantar fascia 18, connecting the heel 12 to the head of
the
metatarsals 20, forms the base of the truss. The plantar fascia simulates a
cable
attached to the heel and metatarsophalangeal joints such that when the heel
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bone is pulled by the Achilles tendon during ambulation, the heel bone
slightly
rotates posteriorly and stretches the plantar fascia.
[0037] During ambulation, the foot truss 10 must tip over to enable a
person to take a step forward. In order for the foot truss 10 to tip over, an
increased translation force 24 must be applied to the heel end of the foot
truss
until the heel lifts off the ground. The translation force 24 is applied to
the
heel end of the foot truss through the Achilles tendon to the knee joint 26.
The
translation force 24 increases the tension in the plantar fascia 18 until heel
lift
off, at which point the tension in the plantar fascia 18 is at a maximum.
[0038] Figs. 1a-1b further depict a reverse truss 22 that is designed to
limit the tension on the plantar fascia 18 by reducing the mechanical work and
force required to tip over the foot truss 10 during ambulation. The reverse
truss
22 reduces the tension on the plantar fascia 18 by providing an assistive
force 28
from a posterior node 23 of the reverse truss 22 to the knee joint 26. The
assistive force 28 reduces the translation force 24 that is responsible for
the
tension in the plantar fascia 18 during ambulation. Further, the reverse truss
22
by way of the assistive force 28 provides enough lift through the posterior
node
23 of the reverse truss 22 to prevent hyperextension of the plantar fascia
during
ambulation.
[0039] Figs. 2a-2b illustrate a side view and back view perspective,
respectively, of an embodiment of the device 30 that reduces tension in
plantar
fascia during ambulation, as provided herein. As shown Figs. 2a-2b, device 30
includes a truss structure 32, an upper anchor 34, and an actuator 36.
[0040] The truss structure 32, illustrated in Fig. 3, includes a
posterior
portion 38, a lateral portion 40, a medial portion 42, a lateral end 44, and a
medial end 46. The lateral end 44 may align with the lateral
metatarsophalangeal
joint and the medial end 46 may align with the medial metatarsophalangeal
joint
of a user's foot. The alignment of the lateral end 44 and medial end 46 of the
truss structure 32 to the relative metatarsophalangeal joints (the joints
connecting the metatarsals to the phalanges) allows plantar fascia to maintain
mobility without over extending and injuring the plantar fascia.
[0041] The truss structure 32 may be constructed from a variety of
materials that result in a rigid, semi-rigid, or flexible structure. For
example, the
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truss structure 32 may be constructed from, although not limited to, steel,
iron,
titanium, various metal alloys, polymeric materials, or any combinations
thereof.
Further, the truss structure 32 may include a hinge in the lateral portion 40
and
medial portion 42 to provide additional freedom of movement of the foot during
ambulation.
[0042] The truss structure 32 may further include at least one
stabilizing
element 48. The stabilizing element 48 may be any stabilizing mechanism that
aids the truss structure in maintaining operability with a user's shoe during
ambulation. Examples of a stabilizing element 48 include, but are not limited
to,
a grommet, clasp, hook, clamp, fastener, latch, bolt, or any combinations
thereof.
[0043] Device 30 may also include a securing mechanism 50 configured to
secure the truss structure 32 to a user's shoe. Examples of the securing
mechanism 50 include, but are not limited to, straps, belts, ropes, elastic
material, hook and loop material, or any combinations thereof. In one example,
the securing mechanism 50 may extend from the lateral portion 40 of the truss
structure 32 to the medial portion 42 of the truss structure 32. The securing
mechanism 50 may include a fastener element 56. The fastener element 56 may
be any fastener element known to those skilled in the art including buckles,
pins,
latches, clips, hook and loop systems (e.g., VelcroTm), or combinations
thereof.
[0044] The securing mechanism 50 may include at least one dorsal strap
52 that extends dorsally (over the top of a user's shoe) from the lateral
portion of
the truss structure 32 to the medial portion 42 of the truss structure 32, and
at
least one ventral strap 54 that extends ventrally (below the bottom of a
user's
shoe) from the lateral portion 40 of the truss structure to the medal portion
42
of the truss structure 32. The dorsal strap 52 is preferably located above the
metatarsophalangeal joint, serving as a pivot point in the foot truss 10. The
ventral strap 54 is preferably located at the midpoint of the reverse truss
22.
[0045] Figure 3 depicts the dorsal strap 52 as two separate straps that
are
joined by a faster element 56. However, the dorsal strap 52 and the ventral
strap
54 may each be a continuous strap, respectively, that joins the lateral
portion 40
to the medial portion 42.
[0046] It is contemplated that the truss structure 32 may be secured to
the outside of a user's shoe. Alternatively, the truss structure 32 may be
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configured to be inserted into a user's shoe. In addition, the truss structure
32
may be fully integrated within the structure of a user's shoe.
[0047] The truss structure 32 may further comprise a heel support to
provide additional support to the plantar fascia during ambulation. For
example,
the posterior portion 38 of the truss structure 32 may have a cupped heel
support securely connected to the posterior portion 38. The actuator 36 may be
directly attached to the heel support or the posterior portion 38 of the truss
structure 32.
[0048] Device 30 includes an upper anchor 34 that is proximally located
a
fixed or adjustable distance from the truss structure 32. For example, the
upper
anchor 34 may be positioned at the user's ankle, the user's calf, the user's
knee
joint, or above the user's knee joint, for example, at the user's lower or
upper
thigh. In yet another contemplated example, the upper anchor 34 may be
anchored to the user's hip or waist. Additionally, the upper anchor 34 may
wrap
around the knee joint and also extend upward to wrap around a person's upper
thigh or even waist to provide additional support. It is contemplated that the
position of the upper anchor 34 is adjustable such that a user could adjust or
modify the placement of the upper anchor 34 anywhere along the user's leg, hip
or waist.
[0049] In one example, the upper anchor 34 is configured to fit around a
portion of a user's leg. For example, the upper anchor 34 may be configured to
fit around a user's knee joint, for example, as a knee brace. The upper anchor
34
may comprise a connector element 60 on the posterior portion 62 of the upper
anchor to secure the upper anchor 34 to the actuator 36. The connector element
60 may include any connector element known to those skilled in the art
including hooks, rings, pins, latches, clips, adhesive, hook and loop systems,
or
combinations thereof. For example, the connector element 60 may be a D-ring
that is connected directly to the posterior portion of the upper anchor 34.
Alternatively, as shown in Fig. 4, a D-ring may be strapped to the upper
anchor
with a hook and loop material to allow a variable positioning of the D-ring
and to
allow the force of the actuator to spread around the knee joint. In one
embodiment, the D-ring may be sewn or otherwise integrated into the upper
anchor 34.
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[0050] The upper anchor 34 may be constructed of various materials. In
one example, the upper anchor 34 may be a conventional knee brace.
Alternatively, the upper anchor 34 may be constructed from injection molded
plastics, metal, carbon fiber, various fabrics, or combinations thereof
[0051] The device 30 includes an actuator 36 that couples the posterior
portion 38 of the truss structure 32 to a posterior portion of the upper
anchor
62. The actuator 36 is designed to provide assistive force 28 to urge heel
lift
during ambulation such that the tension in the plantar fascia is reduced. At
heel
lift, the maximum tension in the plantar fascia is attenuated because the
actuator
36 transmits some of the force applied to the plantar fascia towards the upper
anchor 34. As a result, the tension in the plantar fascia is reduced which
allows
the plantar fascia to heal with reduced risk of re-injury during ambulation.
[0052] The actuator 36 may be made of any material that provides
adequate assistive force 28 to urge heel lift during ambulation. The actuator
36
may be a mechanical, electromechanical or elastic actuator. In addition, the
actuator 36 may be calibrated to apply a range of assistive force magnitudes.
The
actuator 36 may include elastic material, non-elastic material, a spring, or
combinations thereof. The length of the actuator 36 is such to provide
adequate
tension to the truss structure 32 to relieve tension in the plantar fascia
during
ambulation.
[0053] The actuator 36 may be attached to the posterior portion 38 of
the
truss structure 32 and to a posterior portion 62 of the upper anchor 34 by any
connecting mechanism known to one skilled in the art. For example, as shown in
Figs. 2a-2b, the actuator 36 is connected to the posterior portion 38 of the
truss
structure 32 by an S-hook, the actuator 36 is then threaded through a D-ring
on
the posterior portion 62 of the upper anchor 34, and then the actuator 36 is
secured again to the posterior portion 38 of the truss structure 32 by an S-
hook.
Alternatively, as shown in Fig. 5, the actuator 36 may be connected to the
posterior portion 38 of the truss structure 32 by an S-hook and directly
connected to a posterior portion 62 of the upper anchor 34 by an S-hook.
[0054] The actuator 36 may further include a tension sensor 64, as shown
in Fig. 4, enabled to determine the amount of assistive force provided by the
actuator 36 on the truss structure 32. The tension sensor 64 may be wirelessly
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or otherwise connected to a computing device that can calculate the mechanical
work being performed by a user's foot.
[0055] The actuator 36 may further include a tension adjustment
mechanism 66. The tension adjustment mechanism 66 may be any tension
adjustment means that is known by those skilled in the art. For example, the
tension adjustment mechanism 66 may be a manual tension adjustment
mechanism or an automatic tension adjustment mechanism.
[0056] The manual tension adjustment mechanism may include
modifying the position of the upper anchor 34, the position of the connector
element 60 of the upper anchor, or the position of the posterior portion 38 of
the
truss structure 32. Alternatively, or in addition to, the manual tension
adjustment mechanism may include modifying the tension provided by the
actuator 36. For example, the manual tension adjustment mechanism may
include tightening or loosening straps securing a connector element 60, such
as a
D-ring, to the posterior portion 62 of the upper anchor to vary the provided
tension. The manual tension adjustment mechanism may include replacing the
actuator 36 with a different actuator that provides more or less tension.
[0057] The automatic tension adjustment mechanism may include an
electrical system for modifying the assistive force provided by the actuator
36. It
is contemplated that the tension sensor 64 may be cooperatively connected to
the automatic tension adjustment mechanism. For example, if the tension sensor
64 indicates the assistive force is too high or too low, the automatic tension
adjustment mechanism automatically adjusts the assistive force provided by the
actuator 36 to yield an assistive force that is in an optimal and comfortable
range
for supporting the plantar fascia.
[0058] In an embodiment, the device 30 includes an upper anchor, which
in the embodiment illustrated in Fig. 5 is brace 68, adapted to be secured to
a
user's leg at the user's ankle up to beneath the user's hip and an attachment
point 70 adapted to be secured adjacent to the posterior portion of a user's
heel.
The actuator 36 couples the brace 68 to the attachment point 70, such that the
actuator 36 pulls the attachment point 70 towards the brace 68.
[0059] The attachment point 70 may be any connecting mechanism that is
known by one skilled in the art. Examples of the attachment point 70 include,
but
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not limited to, a hook, bracket, latch, ring, loop, or any combination
thereof.
Further, the attachment point 70 may be a portion of the truss structure 32.
Alternatively, the attachment point 70 may be integrated into a user's shoe,
as
shown in Fig. 5.
[0060] The present disclosure also provides a method of mitigating
plantar fasciitis including providing device 30 disclosed herein, associating
the
truss structure 32 with a user's shoe, inserting a user's foot into the shoe,
and
securing the upper anchor to a user's leg. The method includes the actuator 36
urging heel lift during ambulation, thereby relieving tension in the plantar
fascia.
[0061] The method disclosed herein may be used to not only treat plantar
fasciitis but also a wide range of conditions that originate with compromised
foot
or ankle activity, such as Achilles tendonitis.
[0062] It should be noted that various changes and modifications to the
embodiments described herein will be apparent to those skilled in the art.
Such
changes and modifications may be made without departing from the spirit and
scope of the present invention and without diminishing its attendant
advantages.
For example, various embodiments of device 30 may be provided based on
various combinations of the features and functions from the subject matter
provided herein.
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