Note: Descriptions are shown in the official language in which they were submitted.
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STRETCHING DEVICE FOR USE IN THE TREATMENT OF CARPAL TUNNEL
SYNDROME
FIELD OF THE INVENTION
The present invention relates to a stretching device for use in the treatment
of Carpal
Tunnel Syndrome (CTS) or repetitive strain injury, and more particularly a
stretching device
adapted to apply traction to a user's wrist by stretching the user's hand away
from their forearm.
BACKGROUND OF THE INVENTION
The carpal tunnel is formed in the wrist by the carpal bones and the
transverse carpal
ligament. The tendons which flex the fingers and the median nerve pass from
the forearm to the
hand through the carpal tunnel. Wrist level median nerve entrapment, now more
commonly
known as Carpal Tunnel Syndrome, is caused by pressure on the median nerve in
or near the
carpal tunnel. During finger and wrist movement, the finger flexor tendons rub
against each
other and against the walls of the carpal tunnel. This in turn causes swelling
or thickening of the
tendons which then squeeze against the median nerve causing numbness,
tingling, and pain in the
wrist and hand. These are the primary symptoms of Carpal Tunnel Syndrome. A
person with
Carpal Tunnel Syndrome may also experience in one or both hands, dry shiny
skin, a burning
sensation, weakness, and an inability to clench his/her hand into a fist.
Commonly, affected
persons awake in the middle of the night in pain and find extensive numbness
in the hand. The
feeling of CTS pain may spread to the forearm, and in severe cases, as far as
the shoulder.
Carpal Tunnel Syndrome primarily affects individuals between the ages of 30
and 60, and
poses a serious occupational health problem. Strenuous use of the hand such as
sustained
grasping, twisting, or turning, or frequent use of the hand in repetitive
tasks such as typing or
assembly line work, are believed to be aggravating factors.
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In the past, various treatments have been designed to try to alleviate CTS
symptoms.
Traditional forms of treatment have included splinting of the wrist to limit
the range of the
motion during sleep and work. For example, U.S. Patent 5,478,306 to Stoner
discloses a band of
flexible material which is sized to be secured around the hand and adjacent
forearm. The device
of Stoner, however, does not provide active relief of the effects of CTS.
Another option is to
give to the affected person cortisone shots. to decrease tendon inflammation.
If these types of
treatments fail, the last resort is usually surgery to reduce the pressure on
the median nerve.
Heretofore, however, CTS treatments have required the attendance of medical
practitioners,
often delaying relief from CTS symptoms for hours or even days.
U.S. Patent 5,632,726 to Repice et al discloses a device which is mounted on a
traction
machine to provide traction to the wrist of a person suffering from CTS. Such
devices are
cumbersome and unnecessarily expensive and must be operated by professionals.
SUMMARY OF THE INVENTION
To at least partially overcome the disadvantages of previously known apparatus
and
methods for alleviating CTS symptoms, the present invention provides a
stretching device for
applying traction to a user's wrist, and which includes a wristband sized to
encircle the wrist, and
which is coupled to a tensioning strap which may be biased by the user to
apply a forward
tensioning force on the user's hand.
It is an object of the invention to provide a stretching device which
effectively treats CTS
or repetitive strain injuries, without the need to use splints, drugs, surgery
or otherwise attend to
treatment by medical personnel.
It is another object of the invention to provide a device for treating CTS
which can be
used by the individual user without the need for complicated or expensive
intervention or
assistance.
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It is another object of the invention to provide a stretching device which can
be used by a
person suffering from CTS in home or office environments, and which
effectively relieves the
compression of the median nerve at the wrist.
It is a further object of the invention to provide a stretching device adapted
to apply
traction to a user's wrist to relieve the pressure on the median nerve, and
which produces a
resulting decrease in the symptoms of Carpal Tunnel Syndrome.
A further object of the invention is to provide an inexpensive stretching
device for use in
the treatment of Carpal Tunnel Syndrome which may be easily and economically
manufactured.
To at least partially achieve the foregoing objects, the invention provides a
stretching
device adapted to provide a tensioning force between a user's forearm and
hand. The stretching
device comprises a wristband adapted to be encircled about the wrist of a
person suffering from
Carpal Tunnel Syndrome, and a tensioning strap which is attached to the
wristband. Most
preferably, the wristband has a size selected to substantially prevent its
sliding movement past
the user's hand once it has been positioned about the wrist. By way of non-
limiting example, the
wristband may comprise webbing strap made of nylon or flexible or semi-
flexible cloth or
material, an oval or circular ring capable of encircling the wrist, or a cuff,
moulded or otherwise,
or any combination of the above elements.
The tensioning strap is used to apply a tensioning force on the wristband in a
forward
direction distally outward from, and generally parallel to, the longitudinal
extent of the forearm.
The tensioning strap may, by way of non-limiting example, comprise webbing
strap made of
nylon or other flexible fiber or cloth material, an elastomeric webbing strap
or tubing, or in a less
preferred embodiment, may comprise a rigid or semi-rigid rod or member. In a
simplified
construction, the tensioning strap could be formed as a continuous loop
secured at each of its
ends to the wristband, however, more preferably, the tensioning strap is
adjustable in length to
permit use of the stretching device by users of different heights. With the
wristband secured
about the user's wrist, the forward tensioning force on the wristband causes a
distal edge portion
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of the wristband to press forward against the base of the hand at the area
where the hand joins
with the wrist. The application of a forward tensioning force to the user's
hand while the user's
forearm is pulled in the opposite direction or held in a generally fixed
position applies traction to
the user's wrist, causing a reduction of the compression of the transverse
carpal ligament and an
opening of the carpal tunnel to alleviate pressure on the median nerve. Such
tensioning also
stretches the tendons that pass through the carpal tunnel.
The user may apply tension to the tensioning strap by attaching it to a door
handle, jamb
or other fixed object, and pulling backward. Most preferably, however, the
tensioning strap is
sized to extend about the foot of the user's outstretched leg, whereby the
user can tension the
tensioning straps by holding his or her arm in place and flexing his or her
foot in a forward
manner.
Optionally, the tensioning strap can also be provided with a foot harness to
ensure that
the tensioning strap remains properly positioned at the ball of the user's
foot. Such harness
could be made sizable in order to fit snugly over the user's shoe or foot.
In use, with the wristband in place about the user's wrist, the end of the
tensioning strap
which is remote from the wristband is engaged by the user's foot. To apply
traction, the user
tensions the tensioning strap by extending his or her foot forwardly while
holding his or her
forearm in a fixed orientation to resist such motion, with or without
assistance from the other
arm. The forward extension of the user's foot tensions the tensioning strap
and applies a forward
stretching force against the base of the user's hand where the hand merges
with the wrist.
In one aspect, the invention provides a stretching device which includes a
wristband
configured to be releasably secured to the wrist of a person suffering from
Carpal Tunnel
Syndrome and includes one or more adjustable webbing or tensioning straps
attached to the
wristband and extending therefrom adapted so as to be wrapped around the
user's foot or feet.
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Accordingly, in another aspect, the invention resides in a stretching device
actuatable by
a user's foot for applying a forward tensioning force to a user's wrist
comprising,
a wristband having a longitudinal length selected to substantially encircle
said wrist while
preventing sliding movement past said user's hand,
a tensioning member extending from a lateral edge of said wristband, said
tensioning
member being engageable by said foot, whereby the flexure of said foot applies
a tensioning
force on said tensioning member and wristband.
Accordingly, in another aspect, the invention resides in a stretching device
for use in the
treatment of carpal tunnel syndrome comprising:
a wristband having a longitudinal length selected to substantially encircle a
user's wrist,
a flexible tensioning strap extending from a first end to a second end,
said first end of said tensioning strap being secured to said wristband at a
plurality of
locations along the longitudinal length of said wristband,
said second end being adapted for releasable engagement by a biasing member
selected
from a door handle, a door jamb, furniture and a user's foot.
BRIEF DESCRIPTION OF THE DRAWINGS
Further aspects and advantages of the present invention will become apparent
from the
following description, taken together with the accompanying drawings, in
which:
Figure 1 is a perspective view showing a stretching device in accordance with
a preferred
embodiment of the invention prior to attachment to a user;
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Figure 2 shows a partial perspective view showing the attachment of the
stretching device
of Figure 1 to the wrist of a user;
Figure 3 shows a perspective view of the stretching device shown in Figure 1
in an
operational configuration used to apply a stretching force to the user's hand
at the wrist;
Figure 4 shows a second perspective view of the stretching device shown in
Figure 3 and
illustrating a preferred manner of applying a stretching force to the user's
hand at the wrist;
Figure 5 shows an alternate construction of the stretching device shown in
Figure 1
featuring a tension indicator, and
Figure 6 shows an alternate embodiment of the stretching device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is made to Figures l and 2 which show a stretching device 10 used in
the
treatment of Carpal Tunnel Syndrome occurring in a user's wrist 12 (Figure 2).
Figure 1 shows
the device 10 as including a flexible wristband 14 and a tensioning strap 16.
The wristband 14 is
adapted to be releasably secured about the user's wrist 12 and most preferably
is made from
rectangular Nylon webbing 18 having a lateral width of between 1 and 3 inches
and a
longitudinal length of between 6 and 10 inches. The wristband 14 is secured in
position about
the wrist 12 by means of a releasable hook and loop fastener which comprises
loop fastener
portion 22 which is spaced toward one longitudinal end portion, and a hook
fastener portion 24
spaced toward the other end. The loop fastener portion 22 and hook fastener
portion 24 have
longitudinal lengths selected to permit the wristband 14 to be adjustably
secured about wrists of
differing circumferences, while substantially preventing the sliding movement
of the wristband
14 forwardly past the user's hand 26 (Figure 2). When the webbing 18 is
positioned encircling
the wrist 14, as shown in Figure 2, the loop fastener portion 22 and hook
fastener portion 24 are
engaged, releasably securing the end portions together.
Figures 1 and 3 show best the tensioning strap 16 as being joined to the
wristband 14 so
as to extend as an elongated loop about the foot 30 (Figure 3) of the user's
outstretched leg 32.
The tensioning strap 16 is comprised of two elongated flexible nylon webs
36,38 which each
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extend from respective proximal ends 36a,38a to respective distal ends 36b,
38b. The proximal
ends 36a, 38a are attached to the wristband 14 by stitching so as to extend
from a distal edge 29
of the wristband 14 in an orientation generally perpendicular to the
longitudinal direction of the
webbing 18. The webs 36,38 are made from webbing having a width between about
1 and 3
inches. As will be described, the webs 36,38 are secured to the webbing 18 at
longitudinally
spaced positions selected so that when the wristband 14 is secured about the
wrist 12, the webs
36,38 extend across the palm 27 and back 28 of the user's hand 26,
respectively. At distal end
36b, a buckle 40 is included for adjustably and releasably securing the distal
end 38b thereto so
as to provide the tensioning strap 16 as a connected loop. Figure 1 shows best
the web 36 as
having a shorter length than web 38. It is to be appreciated that the overall
length of the web 36
is selected so that when the distal ends 36b,38b are joined, the buckle 40
locates along a side
portion of the outstretched tensioning strap 16 spaced from the users' foot
30.
In Figures 2, 3, and 4, the device 10 is shown whereby the webs 36,38 are
spaced from
each other such that when the wristband 14 is placed about a user's wrist 12,
the webs 36,38
locate approximately on opposite sides of the user's arm 34. As will be
described, with this
configuration the wristband 14 provides an evenly balanced forward tensioning
force on the
user's hand 26 during the use of the device 10. Furthermore, as shown in
Figure 3, the wristband
14 is preferably aligned so that the planar surface of the webs 36,38 run
along opposing sides of
the outstretched hand, with the lateral width of one webbing strap 36
juxtaposed to the palm 27
of the hand 26, and the lateral width of the other webbing strap 38 juxtaposed
to the back 28 of
the hand 26.
In use the wristband 14 is secured about the user's wrist 12 by wrapping the
webbing 18
snugly about the wrist 12 with the web 36 oriented to extend across the palm
27 of the hand 26
and the web 38 oriented to extend across the back 28 of the user's hand 26.
With the wristband
14 secured in position, the distal end 38b of web 38 is looped about the ball
of the user's foot 30,
and inserted through buckle 40, securing it to web 36. The overall length of
the loop of the
tensioning strap 16 as formed by the web 36,38 is adjusted to extend to
marginally less than the
length of the user's outstretched leg 32 when the arm 34 of the user is held
in an orientation with
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the user's forearm bent at about ninety degrees parallel to the outstretched
leg, as shown in
Figure 3. Once the desired tensioning strap 16 length has been determined for
a particular user,
the tensioning strap 16 is looped around the ball of the foot 30 without need
for significant length
adjustment.
As shown in Figure 4, to relieve the symptoms of CTS, the ball of the foot 30
is flexed in
forward motion as shown in the direction of arrow 50, while the user's forearm
is held rigidly in
position parallel to the tensioning force at the user's side. Optionally, the
user's free hand 52
may be used to assist in resisting the forearm from forward movement. The
flexure of the foot
30 tensions the tensioning strap 16 which in turn pulls the wristband 14
against the user's hand
26. As the wristband 14 is pulled forwardly, its distal edge 29 presses
against the base of the
hand 26 where the hand 26 joins with the wrist 12. The forward tensioning
force of the
tensioning strap 16 and the resistance of the user's arm 34 to forward motion
causes a stretching
at the wrist 12, and applies traction thereto. The traction is preferably
applied in cycles, which
for example, preferably comprises 5 seconds of applied tension followed by 5
seconds of rest for
about 3 minutes.
The application of traction to the wrist 12 of the user helps to open the
carpal tunnel
which reduces pressure on the median nerve and results in a decrease in the
symptoms of Carpal
Tunnel Syndrome. The stretching device 10 is an effective and simple way to
treat this injury
and relieve the suffering of those persons affected.
While the preferred embodiment of the invention illustrates a buckle 40 as
being used to
secure the ends of the webs 36,38, the invention is not so limited. Other
mechanisms to permit
adjustment of a two-part tensioning strap are also possible and will now
become apparent. In a
less preferred embodiment the tensioning strap 16 could be provided as a
single continuous strap
secured at each of its proximal ends directly to the wristband 14. In further
embodiment, the
tensioning strap 16, whether a single continuous strap or a connected pair of
individual straps,
could comprise elastomeric webbing or other elastomeric material to provide a
more gradual
increase in force to the wristband 14.
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Similarly, although the preferred embodiment describes the loop formed by the
tensioning strap 16 as being sized to extend about the user's foot 30, the
invention is not so
limited. If desired, a longer or shorter tensioning strap 16 could be provided
with the tensioning
strap 16 configured to be secured to a fixed object, such as a door knob or
desk, and tension
applied by the user pulling his or her arm 34 in a backward direction, with or
without the
assistance of the user's free hand 52.
Although the preferred embodiment describes the tensioning strap 16 as being
secured to
the wrist strap 14 at a pair of opposed locations, the invention is not so
limited. It is to be
appreciated that the tensioning strap 16 could be joined to the wristband 14
by three, four or
more radially placed straps, which are positioned to provide a substantially
even tensioning force
on the wristband 14.
In an alternate construction as shown in Figure 5 the tensioning strap 16 is
formed as a
single strap joined to the wristband 14 through two connecting straps 54,55.
The tensioning
strap 16 in this embodiment also features a foot loop 58 at its furthest end.
Optionally, the
tensioning strap 16 may further include a tension measuring device 56, such as
a spring gauge or
scale, which enables the user to objectively observe the optimum amount of
tension and better
control this self administered therapy.
In an alternate embodiment, the wristband 14 may be provided with a quilted
collar or
other suitable padding (not shown) along its distal edge 29 for increased user
comfort.
While in the preferred embodiment the tensioning strap 16 is fixed to the
wristband 14 by
stitching, other constructions are also possible. For example, the proximal
ends of the tensioning
strap 16 may be formed as eyelets or loops, with the wristband 14 passing
through both eyelets
thereby interlocking the wristband 14 to the tensioning strap 16. Such an
arrangement would
allow the proximal ends of the tensioning strap 16 to be freely positioned
about the perimeter of
the wristband 14.
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In a further embodiment as shown in Figure 6, a wrist-engaging strip 80 is
provided. The
wrist-engaging strip 80 sized to span approximately half of the circumference
of the wrist 12 and
includes eyelets 82 at both of its ends. A tensioning-cinching loop 84 is
passed through both
eyelets 82 of the wrist-engaging strip 80, thereby interlocking the tension-
cinching loop 84 and
the wrist-engaging strip 80. Optionally, the longitudinal length of the
tensioning-cinching loop
84 may be adjustable through use of an adjustable fastener 86. To position the
stretching device
according to this embodiment, the user places his or her wrist 12 proximate to
a portion of the
tensioning-cinching loop 84 and slides the wrist-engaging strip 80 toward the
wrist 12. Then,
when a forward force is applied at the far end of the tension-cinching loop
84, in the same
manner as the tensioning strap 16 shown in Figures 3 and 4, the wrist-engaging
strip 80 and the
portion of the tension-cinching loop 84 proximate to the wrist 12 are forced
together and grip the
wrist 12 at the base of the hand 26. This embodiment of the invention disposes
of the need for
dedicated attaclunent means at the wrist 12 , such as hook and loop fasteners.
Although the invention has been described and illustrated in connection with
certain
preferred embodiments of the invention, it is not intended that the invention
be limited thereto.
Many modifications and variations will now be obvious to those skilled in the
art. It is intended
that the invention cover all alternate embodiments as may be within the scope
of the following
claims.
