Note: Descriptions are shown in the official language in which they were submitted.
W092/03110 2~ , 5~T/US91/05925
PATELLA-~EMORAL BRACE
.
DESCRIPTION
Technical Fleld
This invention relates generally to a knee support
device. More particularly, this invention relates to a
device which supports and stabilizes the knee, including
the patella, to resist abnormal lateral subluxation of the
patella during motion of the knee joint. `-
Background Art
Anterior knee pain (i.e., pain in the forward part of
the knee), is one of the most common complaints that cause
patients to consult a knee specialist. A frequent cause of
such pain is malalignment of the patellofemoral joint which
is often associated with instability of the patella (knee
cap).
Patellar instability usually occurs laterally (i.e.,
in a direction away from the other leg), and is referred to
as "patellar subluxation," "patellar dislocation," or
"patellar hypermobility." In a patient with this knee
disorder, the muscles and ligaments which hold the patella
in its proper position in the knee are malaligned, very
loose or lax. This `condition is caused either by
developmental abnormalities (generally in younger
children), or by injuries to the muscles and/or ligaments
attached to the patella. Because of the very loose
placement of the patella in this condition, the patella may
become misoriented relative to its normal position during
flexion/extension rotation of the knee joint (i.e., during
normal "bending" of the leg at the knee joint). Such
misorientation usually occurs when the joint is extended
under stress, such as during strenuous physical activity in
which the knee is carrying an increased load while it is
rotating.
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Not only can patellar subluxation cause severe pain,
the knee is also more prone to give way (buckle) under the
strain of a load placed thereon when the patella is not
properly oriented. Moreover, continued or frequent
abnormal displacements of the patella can cause severe
degeneration of the patella and the surrounding knee
structure.
The conservative treatment of patellar instability
often incl~des muscle rehabilitation, medication, and/or
activity modification. In addition, those skilled in the
art have developed numerous types of knee braces to assist
in the treatment of patellar instability. Such braces
range from very simple to quite complex and have been
successful in the treatment of patellar instability to
varying degrees.
A simple knee sleeve is often used to provide static
patellar support. The sleeve is generally made of an
elastic material and has an opening through which the knee
cap protrudes. When thus positioned, the sleeve exerts a
static force on the knee to assist in maintaining the
patella in proper alignment.
Another prior art bracing device comprises an
infrapatellar strap. The strap is wrapped around the knee
so as to suppo~t the patella during motion of the knee
joint. ~`
Still another prior art device comprises a bracing pad
held in a lateral position with respect to the patella by
means of an elastic sleeve and a plurality of elastic
straps. This device is intended to apply a medially
displacing force to the patella (i.e., a force in a
direction toward the other leg), and maintain constant
pressure during flexion, extension, and rotation of the
knee.
Despite the limited success of some prior art devices
in treating patellar instability, the exact function of
many of the devices is unclear. For example, some prior
art devices may help alleviate pain for a variety of
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reasons. The warmth the device provides to the knee may be
therapeutic. Similarly, sensory feedback may be altered,
thereby reducing the patient's awareness of discomfort.
Likewise, a possible alteration in circulation is another
potential effect of many devices. These nonspecific
mechanisms might help explain the potential effectiveness
of some prior art patellar bracing devices.
Many existing brace devices are also subject to
shifting on the user's knee during movement of the knee
joint. Of course, such shifting may cause the brace to
become misaligned, thereby significantly reducing the
functional effectiveness of the brace.
In addition, the physiology of the knee is such that
the patella slips deeply into the cavity provided for it
when the knee joint is in hyperextension. In such cases,
the structure of existing brace devices is such that the
patella may slip below the bracing member and rotate
thereunder. The bracing device is thereby rendered largely
ineffective.
Further, the mechanical function of existing devices
seems limited to applying a medial force to the lateral
aspect of the patella in patients with patellar tracking
problems. While this function is believed to be based upon
sound biomechanical principles, it treats only one cause of
patellar instability. There is no known evidence that this
function is applicable in treating any other causes.
Consequently, there remains a need for a bracing device
which more completely enhances and facilitates patellar
stability.
Disclosure of Invention
In accordance with the invention as embodied and
broadly described here_n, a knee brace is disclosed in one
embodiment of the present invention as including an
elongate annular elastic sleeve member which is sized so as
to entirely surround the user's knee and to be held in
place by elastic forces. The elastic sleeve member may
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have formed therein a pocket or other such opening into
which a brace plate may be inserted. The brace plate is
formed of silicone or other similar semi-rigid, semi-
flexible material, and includes a contacting surface which
is shaped to conform to the lateral surface of the patella.
Attachment straps are fixed directly or otherwise operably
coupled to the brace plate and may extend from the elastic
sleeve at points directly above and below the patella. The
straps are of a sufficient length to pass around the medial
side of the knee, and acro~s the back thereof to a point at
the lateral side of the knee. The attachment straps attach
at the lateral side of the knee to the upper and lower cuff
members of a support brace, each cuff member including a
hinging arm which extends along the lateral side of the
user's knee when the cuffs are correctly positioned on the
user's thigh and lower leg. The attachment straps from the
support brace pass behind the user's leg and attach
directly to the hinge arms thereof to secure it to the
user's leg. The attachment of the brace plate straps to
the cuffs of the support brace fix the brace plate in its
proper position relative to the support brace and function
to stabilize and apply a mechanical force to the lateral
side of the patella. The support brace also includes a
hinge attaching the upper and lower hinge arms together,
the hinge including a locking mechanism which prevents
rotation of the hinge beyond a predetermined position in
order to resist hyperextension of the knee. Thus, when the
knee joint is rotated, the patella is prevented from moving
in a lateral direction relative to the remaining structure
of the knee, thus prohibiting misplacement or subluxation
thereof. If desired, the ends of the elastic sleeve may be
folded over the ends of the cuffs of the supporting brace
in order to aid the entire device to function as a integral
unit.
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Brief DescriDtion of Drawin~s
The foregoing and other objects and features of the
present inve..~ion will become more fully apparent from the
following description and appended claims, taken in
conjunction with the accompanying drawings. Understanding
that these drawings depict only typical embodiments of the
invention and are, therefore, not to be considered limiting
of its scope, the invention will be described with
additional specificity and detail through use of the
accompanying dr~wings in which:
Figure 1 is a front view of one presently preferred
embodiment of a patella-femoral bracing device made in
accordance with the principles of the present invention,
showing the device correctly positioned and secured about
a user's knee (with the patella shown in large dashed
lines);
Figure 2(a) is a front view of one presently preferred
embodiment of an elastic sleeve made in accordance with the
principles of the present invention, having included
therein the bracing plate shown in small dashed lines (with
the patella shown in large dashed lines);
Figure 2(b) is a side view of an eiastic sleeve made
in accordance with the principles of the present invention
(also showing the brace plate in small dashed lines and the
patella in large dashed lines);
Figure 3 is a perspective view of one presently
preferred embodiment of a brace plate made in accordance
with the principles of the present invention;
Figure 4 is a partial perspective view of the interior
surface of an elastic sleeve formed in accordance with the
principles of the present invention, showing the pocket and
openings used to secure the bracing plate thereto;
Figure 5 is a perspective view of one presently
preferred embodiment of a supporting brace formed in
accordance with the principles of the present invention,
which is to be located and secured about the user's leg
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over the elastic sleeve, and to which the straps of the
brace plate are to be attached;
Figure 6 is a rear view of the embodiment of the brace
device illustrated in Figure l;
Figure 7(a) is a partial perspective view of a hinge
usable in the support brace and showing the hyperextension
lock unengaged;
Figure 7(b) is a partial perspective view of the hinge
of Figure 7(a) with the hyperextension lock in its engaged
position;
Figure 8 is a perspective view of an alternate
presently preferred embodiment of a patella-femoral bracing
device made in accordance with the principles of the
present invention;
Figure 9 is a perspective view of the supporting brace
of the embodiment of Figure 8; and
Figure lO is a rear view, partially in section, of a
portion of the upper cuff of the supporting brace of the
embodiment of Figures 8 and 9 illustrating the alignment of
the connecting straps.
Best Modes for Carryina Out the Invention
Patellar stability results from dynamic (muscular),
geometric (bone), and static (ligament) components acting
in concert. A deficiency in any or all of these components
may result in patellar instability. Consequently,
effective patellar bracing should enhance and facilitate
all of these components as much as possible.
Dynamic (muscular) stability is best obtained through
proper neuromuscular training; however, muscular effects
can be enhanced through bracing by controlling femoral-
tibial flexion angles. By blocking hyperextension, the
muscles are afforded a greater mechanical advantage in
order to control internal tibial rotation and thus reduce
rotational forces at the knee. Muscle function and
patellofemoral joint reaction are also enhanced by blocking
hyperextension.
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Geometric or bony restraints can likewise be enhanced
if hyperextension is prevented. In some cases,
patellofemoral congruence can be increased with increased
knee flexion (bending). Also, due to the anatomy of the
knee, increasing knee flexion results in a greater surface
of the patella coming into contact with the femur.
It can also help to enhance geometric (bone)
restraints by controlling medial and lateral rotation of
the knee joint. Increased medial rotation at the knee
results in passive subluxation of the patella laterally,
and increased lateral rotation results in active lateral
patellar subluxation secondary to muscle contraction.
Consistent with the foregoing, one presently preferred
embodiment of the patella-femoral bracing device of the
present invention, designated generally at lO, is
illustrated in its entirety in Figure l. As shown, brace
lO is positioned about the knee area of a user's leg so as
to cover the entire knee joint, including the lower part of
the user's thigh and the upper part of the user's lower
leg. Brace lO includes a buttressing system (see bracing
plate 16 in Figure 2(a)) to resist abnormal lateral
subluxation of the patella when the knee approaches
extension. Brace lO also includes a tibial and femoral
shell system (see cuffs 23 and 24) attached to a single-
hinge system (see hinge arms 28 and 29) to facilitatebilateral application of the brace while also controlling
medial-lateral rotation of the knee joint. The hinge
system further includes a hyperextension stop (see Figures
7(a) and 7(b)) to block knee hyperextension, thus improving
patellofemoral bongruity.
It will be readily understood that the components of
the present invention, as generally described and
illustrated in the Figures herein, could be arranged and
designed in a wide variety of different configurations.
Thus, the following more detailed description of the
embodiments of the present invention, as represented in
Figures l through 7(b), is not intended to limit the scope
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of the invention, as claimed, but it is merely
representative of the presently preferred embodiments of
the invention.
The presently preferred embodiments of the invention
will be best understood by reference to the drawings,
wherein like parts are designated by like numerals
throughout.
As shown best in Figures 2(a) and 2(b), device 10
includes an elastic sleeve 11 over which is mounted a
supporting brace 12 (see Figure 5). Sleeve 11 has
incorporated therein a brace plate 16 which is fixed
relative to the elastic sleeve 11. Brace plate 16 includes
or is otherwise operably coupled to a pair of straps 14
which extend from the sleeve 11 and pass around the medial
side and back of the user's leg to connect to the
supporting brace 12.
As shown in Figure 2(a), the elastic sleeve 11 is
sized so as to fit snugly about the user's leg, the sleeve
being sized so that the leg will cause it to stretch
somewhat so that the elastic in the sleeve 11 will hold it
in its proper position thereover.
The sleeve is preferably of a length sufficient to
extend well up the user's thigh and well down the top
portion of the user's lower leg and is preferably formed of
an elasticized material which i5 stretchable in all
directions (as opposed to many types of elasticized
material which stretch in only a single direction). One
example of such material is known as VITALO, which is a
registered trademark of Sport-Medizin of Italy.
As best seen in Figures 2(a) and 4, the elastic sleeve
11 includes a pair of slit shaped openings 15 through which
straps 14 of the brace plate 16 can pass. The straps 14
are of a sufficient length to pass approximately 3/4 of the
distance around the user's leg so as to be attachable to
the supporting brace 12 in a manner explained below.
As shown in Figure 3, brace plate 16 includes a pair
of arms 17 which are located in generally parallel spaced
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WO92/03110 PCT/US91/05925
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apart relationship to form a generally concave patella
contacting surface 19 therebetween. The brace plate 16 may
optionally also include an extension 18 which extends away
from the arms 17 in a generally curvilinear fashion so as
S to conform to the curvature of the knee joint. The
extension 18 functions to protect the lateral side of the
knee from injury or from incidental contact with the
support brace 12. Extension 18 also functions to aid in
anchoring and securing brace plate 16 in its correct
position about the user's knee.
As is best shown in Figures 2(a) and 2(b), the brace
plate 16 (shown in dashed lines) is positioned about the
lateral side of the user's knee so that the concave
contacting surface 19 thereof is located adjacent and
somewhat conforms to the lateral side of the user's patella
33, with the extension 18 thereof extending around the
lateral side of the user's knee joint. Significantly,
brace plate 16 is designed and used to apply force to the
lateral and slightly inferior surfaces of the patella 33 in
order to assist in maintaining proper patellar position, as
will be explained further below. Thus, for example, brace
place 16 may be positioned on a user so as to apply a
lateral force to the patella in an upward direction at an
angle of approximately 30 degrees from the horizontal.
The brace plate 16 of the present invention is
intended to be formed of a semi-rigid, semi-flexible
material. That is, the plate 16 is intended to be
sufficiently rigid to hold its form so as to be easily
positioned in its correct location about the user's knee,
and semi-flexible to allow it to conform to the knee's
anatomy. The preferred materials used in the formation of
bracing plate 16 are silicone and/or polyethylene. For
example, bracing plate 16 may comprise a polyethylene plate
covered with a soft silicone material. However, any
material having similar semi-rigid, semi-flexible
characteristics may be used. Materials used preferably
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have a Shore Durometer hardness of 15 or less as measured
by ASTM Test D-2240-86.
As shown in Figure 4, the interior surface 22 of the
flexible sleeve 11 can include a pocket 20 having opening
21 therein into which the brace plate 16 may be inserted.
The pocket 20 functions to hold the brace plate 16 in its
correct orientation relative to the sleeve 11. The pocket
20 is most useful when the user is mounting the sleeve 11
on the leg, since it holds the brace plate 16 in its proper
orientation while the sleeve 11 is being manipulated into
position about the knee. Although pocket 20 is shown in
the preferred embodiment as the means of holding the brace
plate 16, it is anticipated that the brace plate 16 may be
held in sleeve 11 in any other well known manner such as by
means of adhesive, by being sewn in place, or with
mechanical fasteners.
Slits 15 in sleeve 11 are centered directly above and
below the patella 33 when the sleeve 11 is correctly
positioned on the user ! S leg. The straps 14 pass through
slits 15 until plate arms 1-~ are located approximately
adjacent to the slits 15. In this position, the concave
contacting surface 19 of the brace plate 16 contacts and
completely surrounds a lateral side of the user's patella
33.
Once the user has positioned the sleeve 11 on the leg
in the manner as shown in Figures 2(a) and 2(b), the
supporting brace 12 is then positioned over the exterior
surface 13 thereof in the manner shown in Figure 1. The
supporting brace 12 functions to provide a rigld support to
which the straps 14 of the brace plate 16 can be attached
as will be explained below.
As shown in Figure 5, the supporting brace 12 includes
an upper cuff 23 and a lower cuff 24 which are formed from
a generally U-shaped rigid or semi-rigid material. Each
cuff 23 and 24 may include padding on the interior surfaces
thereof for comfort to the patient in accordance with well
known cuff designs.
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The use of such rigid or semi-rigid cuffs 23 and 24
significantly enhances the hyperextension stop capabilities
of device 10, which will be discussed further below.
Without such cuffs, any hyperextension stop capabilities
5 would rely upon a soft tissue connection with the user's
leg, rendering the hyperextension stop largely ineffectual.
It is also an important feature of the present
invention that the upper and lower cuffs 23 and 24,
respectively, be of a size so that they extend around a
substantial portion of the user's leg. Preferably, the
cuffs 23 and 24 will extend around at least 50% of the
circumference of the portion of the user's leg to which
they arè attached. A supporting brace 12 having cuffs of
this dimension can be more securely attached to the user's
leg than those with smaller cuffs. Further, the larger
cuffs 23 and 24 are less likely to be rotated relative to
the user's leg as a result of an impact or other force
incident thereon during use.
Each oE upper and lower cuffs 23 and 24, respectively,
includes a strap 25 for securing the supporting brace 12 to
the user's leg and a buckle 26 for securing the patella
brace straps 14 to the supporting brace 12. Straps 14 are
thus attachable to the buckles 26 of the supporting brace
12, and are adjustable to adjust the medial pressure
applied to the user's patella 33 by the brace plate 16.
Although straps 14 and buckles 26 are shown in the
preferred embodiment of the present invention, it is
anticipated that any strap and attachment arrangement
allowing for direct attachment of the brace plate 16 to the
supporting brace 12, is contemplated to be within the scope
of the present invention. For example, buckles 26 may be
replaced with snap fasteners, VELCRO fasteners or the like.
Further, if desired, straps 14 may be formed either of a
non-elastic or an elastic material, depending on the
particular bracing characteristics desired.
Each lateral side of the upper and lower cuffs 23 and
24 include an extension arm 27 and 28, respectively, which
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attach together at hinge 30. When the supporting brace 12
is correctly positioned on the user's leg, arms 27 and 28
are located on the lateral side of the userls leg such that
the rotation axis of hinge 30 is located generally
coaxially with the flexion/extension rotational axis of the
user's knee joint, so as to be capable of tracking the
hinging motion thereof. Each arm 27 and 28 has a buckle 29
included thereon which is used to secure straps 25 of the
support brace plate 12.
As best shown in Figures 7(a) and 7(b), the hinge 30
of the support brace 12 includes a locking surface 31 on
arm 27 and a locking hub 32 on arm 28. Where the hinge is
in a flex position (Figure 7a) the locking surface 31 and
the loc~ing huh 32 cannot interengage. ~owever, as the
lS user's knee approaches full extension (Figure 7b), the
locking hub 32 abuts with the locking surface 31 to prevent
any further extension (hyperextension) thereof. This
preferably occurs when the user's knee is extended at about
15 to 20 degrees.
Since the device 10 of the present invention must
cohform to the size of the leg of the user to which it is
to be applied, it is anticipated that the various
structural elements thereof be formed in a series of
different sizes to accommodate different users.
An alternate embodiment 110 of the bracing device of
the present invention is illustrated in Figures 8-10. As
shown, cuffs 123 and 124 are formed so as to spiral around
the user's leg when positioned as described above.
Connecting straps 125 likewise spiral around the user's leg
and attach to buckles 129, as shown best in Figure 9.
Straps 114 are operably coupled to the bracing place (not
shown) through sleeve 111, such as, for example, by means
of sewing; and straps 114 attach to cuffs 123 and 124 by
means of buckles 126. As shown best in Figure 10, buckles
126 are preferably positioned so as to be approximately in
line with the point of origin of straps 125.
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As indicated above, brace plate 16 may not include a
protective extension 18 (see Figure 3). In such case, as
depicted in Figures 8 and 9, hinge arms 127 and 128 may
advantageously be coated with a suitable resilient
material, such as, for example, a resilient plastic
cushioning material. This resilient coating will thus
protect the lateral side of a user's knee from injury or
from incidental contact with the support brace.
In use, referring again to Figures 1 through 7(b)., the
upper cuff 23 is placed against surface 13 of the portion
of the sleeve 11 at the front of the user's upper leg, and
the strap 25 thereof is passed behind the leg and attached
into buckle 29. The strap 25 is then tightened to secure
the cuff 23 firmly against the thigh. Similarly, cuff 24
is placed against surface 13 of sleeve 11 so as to surround
the upper shin area of the front of the user's lower leg,
and the strap 25 located thereon is passed behind the
user's leg and attached to buckle 29. The strap 25 is
tightened to firmly secure cuff 24 to the user's upper shin
area.
As shown in Figures 1 and 6, bracing plate 16 is
integrated through straps 14 with the support brace 12.
This positive connection through straps 14 with bracing
plate 16 allows dynamic force application to the patella
33. As shown, straps 14 wrap around the medial and
posterior aspects of the user's knee, and connect to the
upper and lower cuffs 23 and 24 of support brace 12 such
that the thigh side strap connection is superior to its
origin on the bracing plate 16 and the calf side strap
connection is inferior to its origin on the bracing plate
16 (see Figure 6).
Once the supporting brace 12 is secured over the
elastic sleeve 11 to the user's leg, and the straps 14 are
secured to buckles 26 thereof, the device lO of the.present
invention appears substantially as shown in Figures 1 and
6. If desired, the upper an`d lower ends of the elastic
sleeve 11 may be pulled away from the user's leg and folded
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over the upper and lower portions of the upper and lower
cuffs 23 and 24, as depicted in Figures 1 and 6. In this
manner, the elasticity of the sleeve 11 tends to aid in
securing the support brace 12 in its correct position
relative to sleeve 11. Such integration of sleeve 11 with
support brace 12 also tends to hold the device 10 together
to aid in its functioning as an integral unit and in
maintaining proper brace position throughout the knee's
range of motion.
It is evident from the above disclosure that when the
device 10 of the present invention is attached correctly to
a user's leg, the user's patella 23 will be at least
partially surrounded on its lateral side by the brace plate
16. Since the brace plate 16 is fixed in its lateral
position by straps 14 which are directly attached to
supporting brace 12 at buckles 26 (the support brace 12
itself being securely fixed in position relative to the
user's leg by means of straps 25 and buckles 29, and also
the folded ends of sleeve 11), the user's patella 33 is
prevented from moving laterally with respect to the
remaining structure of the knee. The brace plate 16 can be
secured by straps 14 to continuously provide a pressure in
the medial direction against the side of the patella to
prevent subluxation in the lateral direction. Since
subluxation only occurs in the lateral direction, bracing
such as described in the present invention is sufficient
for its prevention.
Since straps 14 directly fix the location of the brace
plate 16 relative to the arms 27 and 28 of the support
brace 12, flexion/extension rotational motion of the knee
has no detrimental effect on the functioning of the device
10. Regardless of the amount of flexion of the knee joint,
the brace plate 16 remains correctly positioned against the
lateral side of the patella 33 to hold it in its proper
orientation relative to the remaining structure of the
knee. Any tendency of the patella 33 to move in a lateral
direction is resisted by the brace plate 16.
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Significantly, as the user's knee approaches full
extension, two mechanisms create a dynamic force
..plic~tion w: ^h helps to maintain and stabilize the
patella in its correct position, thus reducing lateral
subluxation and hypermobility. First, as the arms 27 and
28 of support brace 12 move towards the full extension
position, the distance between the attachment points of the
ends of each strap 14 increases because of their respective
superior and inferior attachment to cuffs 23 and 24. This
effectively shortens the length of straps 14, thereby
applying a dynamic lateral force to the patella through
bracing plate 16.
Similarly, as the user's knee comes toward full
extension, the user's thigh and calf apply pressure to the
cuffs 23 and 24, and the brace device 10 becomes locked
into extension due to the engagement of locking surface 31
with locking hub 32. As the brace device 10 is forced into
this locked position and the user's knee tries to move into
further extension, the knee begins to back out of the
device 10 posteriorly. As it does so, straps 25 secure the
cuffs to the user's leg, and the user's leg exerts a force
on straps 14. This tightens the straps 14 and applies a
dynamic mechanical force through bracing plate 16 to the
lateral inferior aspect of the patella 33.
Since hyperextension of the user's knee is resisted,
the user's patella 33 has no opportunity to slip below the
brace plate 16. Continuous contact with and lateral
pressure from brace plate 16 is therefore assured.
Referring again to Figures 2(a) and 2(b) and Figure 3,
the extension 18 of the brace plate 16, when properly
positioned on the knee, is located between the lateral side
of the user's knee and the arms 27 and 28 of the supporting
brace 12. The lateral side of the knee is therefore doubly
protected from injury due to impact or other forces
directed at its lateral side. This double protection is a
result of arms 27 and 28 being capable of absorbing lateral
forces along with the extension 18 of the bracing plate 16.
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Arms 27 and 28 also inhibit medial-lateral rotation of the
knee, thereby enhancing the knee~s geometric (bone)
restraints.
It is an important feature of the device 10 of the
present invention to have the medial side of the user's leg
be free of any hinge member or hinge arms associated
therewith. This is often important in the treatment of a
patient subject to patellar subluxation in that, generally,
a patient with this disorder experiences the problem in
both knees at the same time. In such cases, the patient
must wear a device 10 on each leg (each device 10 being a
mirror image of the opposite device). Using the design of
the present invention, a user may easily and comfortably
use a brace 10 on each leg simultaneously, without the
complication of having a portion of one device 10
interfering with its counterpart on the opposite knee.
The present invention may be embodied in other
specific forms without departing from its spirit or
essential characteristics. The described embodiments are
to be considered in all respects only as illustrative, and
not restrictive. The scope of the invention is, therefore,
indicated by the appended claims, rather than by the
foregoing description. All changes which come within the
meaning and range of equivalency of the claims are to be
embraced within their scope.
What is claimed and desired to be secured by Letters
Patent is:
.. . . . . .
,
