Note: Descriptions are shown in the official language in which they were submitted.
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A protective device
The present invention relates to a protective device for
protecting the heel of the hand. The invention may be used
for example when participating in sports such as
snowboarding or skateboarding.
When participating in sports such as snowboarding, ice-
skating or skateboarding, it is common for a person to lose
their balance and fall over. If a person falls face down
towards the ground, it is usual for them to try to protect
themselves by extending their arms, and using their hand to
"break" their fall. This means that their hands contact the
ground first, allowing them to slow the speed at which their
upper body or head will impact the ground (if at all).
Although effective in preventing injury to the upper body
and head, this often results in damage to the hands, wrists
and/or arms.
The bones of the hand and lower arm are shown in Figure 1.
A hand 1 comprises four fingers 2 and a thumb 3. Each
finger 2 comprises three bones, namely a distal phalanx 4,
middle phalanx 5 and proximal phalanx 6. The thumb 3 on the
other hand comprises only two bones, a distal phalanx 7 and
proximal phalanx 8.
The hand 1 further comprises five metacarpal bones 9, to
which each of the proximal phalanges (phalanx bones) of each
finger and the thumb is respectively connected. Connected
to the metacarpal bones 9 are eight carpal bones 10,
arranged in two rows of four. The carpal bones 10 are then
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connected to two bones that form the lower arm, namely the
radius 11 and ulna 12.
A hand of course further comprises a number of ligaments and
muscles and tendons by which the bones are held together and
controlled, and is surrounded by skin. The area of the
underside of the hand given by the metacarpal bones 9 (and
surrounding ligaments, muscles, skin etc.) is known as the
"palm" of the hand. Each metacarpal bone 9 comprises a
bulbous base portion 9a, a thinner shaft portion 9b, and a
bulbous top portion 9c. The area given by the carpal bones
10, the lower half of the thumb metacarpal 9 and the base 9a
of each finger metacarpal 9 is known as the "heel" of the
hand. The joints between the carpal bones 10 themselves and
between the carpal bones 10 and the radius 11 and ulna 12
comprise the wrist joint.
When using the hands to break a fall, typically the hand is
instinctively bent backward by extending the wrist joint so
that the heel of the hand impacts the ground, as shown in
Figure 2. It is believed that this positioning of the hand
makes the force from the impact transmit more effectively
through the carpal bones 20 into the radius 11 and ulna 12
bones of the lower arm, and to some extent directly into the
ends of the radius 11 and ulna 12. This is advantageous as
it reduces the peak forces transmitted and thus the risk of
fracture. Despite this, injuries to the wrist and hand
often cause fractures of the distal radius or carpal bones
or carpal ligament injuries.
The use of protective devices to prevent or reduce injury
when participating in sports such as snowboarding or
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skateboarding is well-known. Such protective devices are
often adapted from wrist splints, which are used to protect
the wrist when it has been injured, and in particular to
reduce movement of the wrist allowing the joint and
associated bones to rest and reducing painful movement. A
typical such protective device is shown in Figure 3. The
protective device 11 comprises rigid protective portions 12
and 13, which are held together by means of releasable
straps 14 and 15. The protective device 11 when worn is
shown in Figure 4. As can be seen, the first protective
portion 12 is positioned on the underside of the hand and
arm, and covers a part of the lower arm, the wrist joint,
and a large portion of the palm. The second protective
portion 13 is positioned on top of the hand and arm, and
covers a similar area to the first protective part 12,
namely a part of the lower arm, the wrist joint, and the
back of the hand up to the joints between the metacarpal
bones and the proximal phalanx bones. Other known devices
only have significant protection on the underside of the
hand and arm.
As can be seen from Figure 4, although the protective device
11 will offer some protection to the hand, wrist joint and
arm in the case of a fall, the movement of the wrist joint
will be restricted by the protective portions 12 and 13.
This will prevent a person from being able to put their hand
in the position shown in Figure 2, and so prevent them from
correctly positioning their hand to optimally break their
fall. The movement of the palm is also restricted. This
means that the protective device is not suitable for
situations in which full mobility of the wrist or palm is
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desirable. Further, the device is bulky and can be
uncomfortable to wear for long periods.
In the light of the above, it would be desirable to have a
protective device for protecting the heel of the hand that
solved or mitigated some or all of the above-mentioned
disadvantages of the prior art.
In accordance with a first aspect of the present invention
there is provided a protective device for protecting the
heel of the hand, comprising:
an impact-resistant protective portion;
a securing means for securing the protective portion to
the hand;
wherein the protective portion is arranged to cover, in use,
the heel of the hand and is so configured and dimensioned
that it does not extend towards the fingers or the wrist
substantially beyond the heel of the hand.
In the event of a fall, the impact-resistant protective
portion of the device provides protection for the wearer
from the impact of the heel of their hand with the ground.
However, as the protective portion does not extend towards
the fingers or the wrist substantially beyond the heel of
the hand, movement of the wearer's wrist is not restricted.
This allows the wearer to position move their wrist to the
optimal position for breaking their fall, and also to move
it freely for any other purpose.
Advantageously, the protective portion does not extend
substantially beyond the heel of the hand. This means the
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protective device is less bulky and more comfortable to
wear.
Advantageously, the protective portion is contoured to fit
5 the heel of the hand. This provides greater protection as
any impact is transmitted over a greater area of the heel of
the hand, and also provides a more comfortable fit.
Preferably, the protective portion comprises a polymer
material. This allows the protective portion to be strong
but also light.
Preferably, the maximum extent of the protective portion in
the direction from the wrist joint to the palm of the hand
is less than 60mm. Preferably, the protective portion is
constructed of a material with a thickness of less than 5mm.
Preferably, the surface area of the protective portion when
projected onto a planar surface is from 1800 to 6000mm2.
Advantageously, the protective portion is arranged to break
under an impact above a pre-determined threshold. This acts
to dissipate some of the force from the impact with the
ground into the protective device itself in the case of a
particularly hard impact.
Preferably, the protective device further comprises a
padding portion arranged to fit between the protective
portion and the hand. This provides greater comfort and
means any impact is transmitted over a greater area of the
heel of the hand. The padding portion may be made of a
flexible foam material.
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The securing means may be removably attached to the
protective portion. This allows the device to be removed
easily. In that case, the securing means may be attached to
the protective portion by means of hook-and-loop fabric
fastening. This provides a convenient fixing mechanism.
Alternatively, the securing means is permanently attached to
the protective portion. In that case, the securing means
comprises an elasticated material. This allows the device
to be removed. The securing means may comprise a fastening
for varying the length of the securing means.
The securing means may be a glove or mitten. This is a
convenient method for securing the device on the hand,
particularly for activities such as snowboarding where
gloves or mittens would already be worn, and provides for
example insulation of the hand as well as protection in the
case of a fall. Preferably, the glove or mitten comprises a
pocket, and the protective portion is arranged within the
pocket. Advantageously, the protective portion can be
removed from and replaced within the pocket. This allows
the protective portion to be removed in the case it is not
needed, and replaced if necessary if it is broken during a
fall.
In accordance with a second aspect of the present invention
there is provided a protective device for protecting the
hand, comprising:
an impact-resistant protective portion;
a securing means for securing the protective portion to
the hand;
wherein the shape of the protective portion is such that, in
use, the protective proportion can cover an area of the
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user's hand extending from the wrist whilst the palm of the
hand and the wrist joint are substantially uncovered by the
protective portion.
In accordance with a third aspect of the present invention
there is provided a protective device for protecting the
hand, comprising:
an impact-resistant protective portion;
a securing means for securing the protective portion to
the hand;
wherein the protective portion is arranged to cover, in use,
at least a part of the hand extending from the wrist, the
protective portion when projected onto a planar surface
having a surface area from 1800 to 6000mm2.
There will now be described, by way of illustration, two
embodiments of the invention, with reference to the
accompanying drawings of which:
Figure 1 shows the bones of the lower arm, wrist and hand;
Figure 2 shows the positioning of the hand when breaking a
fall;
Figure 3 shows a known protective device in an unfastened
configuration;
Figure 4 shows a known protective device in a worn
configuration;
Figure 5 is a bottom view of a protective device according
to a first embodiment of the present invention in a worn
configuration;
Figure 6 is a top view of the protective device in the worn
configuration;
Figure 7 shows a padding portion of the protective device;
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Figure 8 shows a protective portion of the protective
device;
Figure 9 shows the use of the protective device when
breaking a fall;
Figure 10 is a bottom view of the protective device in the
worn configuration;
Figure 11 is a side view of a protective device according to
a second embodiment of the present invention in a worn
configuration;
Figure 12 shows a protective portion of the protective
device.
A first embodiment of a protective device according to the
present invention is shown in Figures 5 to 9. As shown in
Figure 5, the protective device 101 comprises a protective
portion 102 made of a rigid or semi-rigid, suitably impact
resistant, polymer material, which is contoured to fit the
heel of the hand, and extends from base of the heel of the
hand above the wrist joint to the bottom of the palm. A
padding portion 103 is positioned between the protective
portion 102 and the hand and is attached to the inner
contoured surface (not visible in the Figures) of the
protective portion 102. (The padding portion is not visible
in Figure 5, but can be seen in Figures 6 and 7.) Opposed
to inner surface is an outer surface 108 which, in the
embodiment shown, is visible, although in some embodiments
it may be covered by a cover for aesthetic purposes. The
cover may, if desired, fully enclose the protective portion
of the padding portion. As shown in Figure 8, the device
has a circumferentially extending edge which, in the
drawings, is divided into a wrist edge portion 110, a thumb
edge portion 111, a palm edge portion 112, and a return edge
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portion 113. It will be understood that those respective
edge portions are defined merely for convenience; they are
not independent separable structures and together form the
continuous edge.
As can be seen particularly clearly in Figure 8, two hook
pads 104 and 105 of a hook-and-loop fabric fastener are
positioned on, for example adhesively attached to, the outer
surface 108 of the protective portion 102. The first hook
pad 104 is positioned in the vicinity of thumb edge portion
111, and the second hook pad 105 is positioned towards the
return edge portion 113 of the protective portion 102 (that
is, the edge closest to the "little" finger). A securing
means, which consists of an elongate strip 106 of flexible
material having on one side loops of a kind that are
removably attachable to the hook pads 104 and 105. The
elongate strip 106 has a first end attached to the first
hook pad 104, passes between the thumb and palm, around the
back of the hand, and has its second end attached to the
second hook pad 105 (see in particular Figures 5, 6 and 9).
Whilst, in the embodiment shown, the device is attached to
the hand in use by means of an elongate flexible strip
having loops on one side that are releasably attachable to
the hook pads on the protective portion, it will be
appreciated that any suitable fastening means may be used.
For example, the flexible strip may have loops only on its
end portions. Alternatively there may be a flexible strip
fastener that is permanently attached to the protective
portion at either the thumb edge portion 111 or the return
edge portion 113, having a free end that is removably
attached to the protective portion in the vicinity of the
opposed edge of the protective device. The flexible strip
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fastener could alternatively be permanently attached at both
ends but be separable into two portions by means of a clasp.
Another possible arrangement would include an elasticated
flexible strip that is permanently attached at each end to
either the thumb edge portion or the return edge portion.
In practice, the protective portion 102 is held in place on
the hand by the securing means 106 and, being contoured to
fit the heel of the hand, will be retained in place during
normal use. Due to the small size of the protective portion
102, namely the fact that it extends only from the base of
the heel of the hand to the bottom of the palm, movement of
the wrist joint and palm is not or is barely restricted.
However, in the event of a fall the protective portion 102
will be positioned between the hand and the ground, and so
will provide protection to the hand and wrist joint and help
prevent an injury occurring, as shown in Figure 10. As well
as helping the protective device to stay in place during
use, the fact that the protective portion 102 is contoured
to fit the heel of the hand means that the force from the
impact with the ground is distributed evenly across the
entire part of the hand covered, rather than focussed at one
particular point, again helping to prevent an injury
occurring. The padding portion 103 also helps to evenly
distribute the force from the impact with the ground into
the hand.
In the case of a particularly hard impact the protective
portion 102 is designed to crack, which acts to dissipate
some of the force from the impact with the ground into the
protective device itself.
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Typical dimensions for the protective portion would in
practice be as follows:
(i) From wrist edge portion to palm edge portion: 30mm
to 60mm;
(ii) From thumb edge portion to return edge portion:
60mm to 100mm.
It will be appreciated that the dimensions above will
generally increase in proportion to one another. In
general, the dimension (i) will be from 40% to 70%, and
preferably 50% to 60%, of (ii).
The dimensions above are, in the case of a contoured
protective portion such as that shown in the drawings,
measured from a planar projection of the contoured portion.
The protective portion when projected onto a planar surface
thus has a surface area from 1800 to 6000mm2. Preferably,
it has a surface area from 2750 to 5000mm2.
The contouring of the protective portion is, as already
mentioned, such that the surface closest to the hand
generally follows the surface of the heel of the hand. In
practice, the total depth of the protective portion
(including the contouring) is of the order of 1 to 3cm
whilst the thickness of the protective portion is from 0.3
to 0.75mm, and preferably from 0.3 to 0.5mm.
The protective portion may be made of any suitable material
having an appropriate impact resistance. Suitable materials
may include, without limitation, polystyrenes, acrylics,
polyurethanes, polycarbonates, polyamides, polyethylenes and
polypropylenes, either per se or reinforced as appropriate.
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The impact resistance is such as to resist impact under most
conditions of normal use, but is selected to allow breakage
under unusual levels of impact such as would be experienced
in a serious fall. In those circumstances, the severing or
shattering of the protective portion can absorb the more of
the energy resulting from the impact.
A second embodiment of a protective device according to the
present invention is shown in Figures 10 to 12. As in the
previous embodiment, the protective device 201 comprises a
protective portion 202 and a padding portion 203 attached to
the contoured inner surface of the protective portion 202 so
that in use it is positioned between the protective portion
202 and the hand. The device has a circumferentially
extending edge which is divided into a wrist edge portion
210, a thumb edge portion 211, a palm edge portion 212, and
a return edge portion 213; again it will be understood that
those respective edge portions are defined merely for
convenience, and are not independent separable structures
but together form the continuous edge.
However, in this case there are four hook pads 204 to 207
positioned on surface of the protective portion 202 opposite
to the hand, each towards a respective corner of protective
portion 202, and the securing means consists of first and
second elongate strips of flexible material 208 and 209
having on one side loops of a kind that are removably
attachable to the hook pads 204 to 207. The first strip 208
has a first end attached to the hook pad 204 positioned on
the corner of the protective portion 202 where the palm edge
portion 212 and return edge portion 213 meet, and passes
around the back of the hand, between the thumb and wrist
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joint, and has its second end attached to the hook pad 206
on the opposite corner, namely the corner where the wrist
edge portion 210 and thumb edge portion 211 meet. The
second strip 209 has a first end attached to the hook pad
205 positioned on the corner of the protective portion 202
where the palm edge portion 212 and thumb edge portion 211
meet, passes around the back of the hand, and has its second
end attached to the hook pad 207 on the opposite corner,
namely the corner where the wrist edge portion 210 and
return edge portion 213 meet.
Although in these embodiments the protective portions 102
and 202 comprise a solid piece of polymer material, they
could alternatively be made of a perforated material, for
example simply the polymer material with a number of holes
through it. This would make the protective device lighter,
and would also allow air to circulate through the protective
portion making it cooler to wear and aiding in the
evaporation of sweat.
A third embodiment of a protective device according to the
present invention (not shown) comprises a protective portion
as in the previous embodiments. In this embodiment,
however, the securing means is a glove or mitten with a
pocket positioned over the heel of the hand. The protective
portion would be placed within the pocket and so protect the
heel of the hand. The protective portion could be removable
from the pocket, in which case it could be replaced when
broken or simply not required (for example if the gloves or
mittens were simply being worn for warmth, and not during a
sporting activity). Alternatively the protective portion
could be permanently fixed within the pocket.
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Although the foregoing invention has been described in
detail by way of illustration and example for purposes of
understanding, it will be obvious that changes and
modifications may be practised within the scope of the
appended claims.
