AU2006230699A1 - Knee Brace - Google Patents

Description

3834-1.doc -1- O Knee Brace O Technical Field This invention relates to dynamic splints or braces and more particularly to dynamic splints or braces for joints.

Background Art SThe joints of most mammals, including humans are susceptible to damage Cl through accident or just general usage. When damage occurs pain is usually perceived and this results in loss of function of the joint. As a result of pain the person avoids full use of the joint. However, the injury results in derangement of the joint and loss of its range of mobility, reduced elasticity, weakness of the associated muscles and ligaments and eventually loss of the shock absorbing ability of the joint. With the lower limbs, the act of walking, jogging or running generates a shock loading of the joints as the user's feet first contact the ground. This can lead to pain and/or further damage to the joint when the shock absorbing ability of the joint is lost.

Joint support devices are well- known but they tend to either immobilise the joint totally or significantly or only provide partial support, allowing for movement in one plane or another but not reducing actual pressure on the joint itself not giving any shock absorbing facility. For example, the knee joint of humans is susceptible to damage through sporting accidents. This frequently results in damage to the various ligaments of the knee, resulting in loss of lateral stability. Various braces for joints are known but generally only provide lateral support relative to the desired plane of motion. Generally such supports do not significantly reduce the load passing through the joint and none are known to provide shock absorbing capability whilst allowing relatively free movement of the joint in its intended plane of motion. Most of these devices do not provide an exercising facility to the joint, but they are rather restrictive to 3834-1.doc -2full activity of the muscles surrounding the affected joint. Strengthening these _muscles usually helps earlier healing, mobilization restoration of the normal O physiological biomechanics of the joint function, including the natural shock absorbing ability. The other issue not tackled in previous works is transferring C"l some load of the body on the joint from a point of weakness or pain to a stronger or a more convenient or comfortable point, e.g. transferring some Nweight from the medial compartment of an osteoarthritis knee of bow-legged N patient to the lateral compartment.

SAs used in the description and claims the word "joint" is to include multiple C"l joints, such as those found in the neck and spine of a human.

DISCLOSURE OF THE INVENTION In an attempt to ameliorate at least one of the disadvantages of the prior art, the present invention provides a brace for a joint that transfers at least some of the load that normally passes through the joint in normal use via the brace, either between the two sides of the joint or from one side of the joint to another part of the body or an external body.

Preferably the brace provides a shock absorbing function. This may be achieved by providing two or more parts of the brace that are movable relative to each other under load and which are biased apart.

The brace may include a first mounting for attachment to a user's body part adjacent to and to one side of a joint or plurality of joints and a load transfer mechanism for transferring load that travels via the joint or plurality of joints in the absence of the brace from the body to another part of the user's body on the other side of a joint or series of joint or to an external body.

The brace may include a second mounting for attachment to a body part adjacent to and to the other side of a joint or series of joints.

3834-1.doc -3- 0 The first and second mountings may be articulated together to allow desired movement of the joint. The first and second mountings may be articulated O together to prevent or discourage undesired movement of the joint or series of joints.

In another broad form the invention provides a brace for a joint including:

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o a first mounting for attachment to a user's body on one side of the joint; ND a second mounting for attachment to the user's body on the other side of oa joint; the first and second mountings are articulated together via a connection to allow desired movement of the joint or to prevent or discourage undesired movement of the joint or series of joints, or both, and at least one load transfer mechanism for connection to the user's body part on the other side of the joint for movement therewith and connected to the first mounting via said connection, wherein, in use, said load transfer mechanism transfers to the first mounting via the connection at least some of a load that, in the absence of the brace, would travel via the joint, thereby reducing the load placed on the joint.

The first and second mountings may be articulated about a single axis or may be articulated about a complex hinge.

A portion of the load transfer mechanism may be mounted on the second mounting for movement therewith.

The load transfer mechanism may be adjustable for different users.

Preferably the load transfer mechanism includes first and second components telescopically joined together.

3834-1.doc -4-

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O The first and second components may be elongate. The two components may include a first tube and a second member received within the first tube.

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The first component may include a first stop member that limits the movement of the second member relative to the first component in a first elongate direction. A second stop member may be provided to limit the movement of the \second member relative to the first component in the opposite direction.

e¢3 Cl Preferably a biasing member is located between the first stop member and the

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Ssecond component. The biasing member may bias the first stop member and the second component apart.

The biasing member may include a coil spring, air bladder or a solid resilient material. A suitable solid resilient material is a natural or synthetic rubber or another elastomeric polymer.

In a preferred embodiment the invention provides a knee brace that includes a first mounting for attachment to the thigh of a user, a second mounting for attachment to the lower leg of a user, the first and second mountings pivotably attached to each other and at least one load transfer device that, in use, extends to adjacent the sole of the user's foot or footwear, the load transfer device transferring at least part of the load that normally passes through the user's knee when walking, jogging or running from the user's thigh to the ground.

The invention shall be better understood from the following description of a non-limiting embodiment of the invention and the drawings.

Brief Description of the Drawings Figure 1 shows a front perspective view of bio-suspension device for use with a human knee according to an embodiment of the invention in a fully retracted configuration.

Figure 2 shows a rear perspective view of the figure 1 device.

3834-1.doc O Figure 3 shows a front elevation view of the figure 1 device.

.,Figure 4 shows a side elevation view of the figure 1 device.

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SFigure 5 shows a rear perspective view of the figure 1 device in a fully extended configuration.

SFigure 6 shows a side view of part of the lower leg assembly of the figure 1 Cc device showing hidden detail.

SFigure 7 shows an exploded perspective view of a hinge unit of the figure 1 device from one angle.

Figure 8 shows an exploded perspective view of a hinge unit of the figure 1 device from another angle.

Figure 9 shows another side view of part of the lower leg assembly of the figure 1 device with the upper tube and spring omitted to show further hidden detail.

Best Mode of Carrying out the Invention Referring to the drawings there is shown a bio-suspension unit 10 for use with a human knee.

The unit 10 includes an upper mounting 12 adapted to be attached to the thigh of a user and a lower mounting 14 adapted to be attached to the lower leg of a user.

The upper mounting 12 has two lateral upper legs 16a, 16b that engage with hinge assemblies 18a and 18b on either side of the user's knee. The lower mounting 14 has two lateral lower leg assemblies 20a, 20b that engage with the hinge assemblies 18 on either side of the user's knee. The upper and lower mountings 12, 14 may thus pivot relative to each other about hinge axes 22.

The hinge axes are preferably coaxial. The lateral leg assemblies 20 extend 3834-1.doc -6downwards on either side on the user's lower leg and are adjusted so that the _feet 98 engage the ground in use, as will be explained later.

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The upper mounting 12 includes a relatively rigid shell 26 adapted to be positioned on the front of a user's thigh and secured thereto by straps 28a, 28b that extend between loops 30 on either side of the user's leg. The straps 28a, 28b are preferably made of a non-stretch fabric, preferably of a woven plastics material.

SPadding 32 is attached to the inner surface of the shell 26 so as to lie between the user's skin and the shell 26. The shell may be formed of a suitable plastics material. The padding 32 is preferably formed of closed cell foam. Other materials may be used for the shell and the padding.

The upper loops 30a are attached to the outer surface of the legs 16 and the shell 26 is attached to the inner surface of the legs 16. Rivets 33 secure all three components together. Because the thigh of a human tapers towards the knee the shell 26 also tapers downwardly and so the lower loops 30b are sandwiched between the shell 26 and the legs 16. The three components are secured together with rivets 35. Other fasteners or methods of fastening may be used, such as threaded fasteners, gluing, welding or the like.

The legs 16 are preferably formed of a lightweight but strong material, such as aluminium. The legs 16 are generally planar and have two main sections. The first, lower, section 34 in use extends generally vertically and the second, upper, section 36 extends upwards and outwards from the top of the lower section 34. The two sections 34, 36 are formed integrally and delineated by crease line 38. When the legs are preferably formed of aluminium, aluminium alloy or similar material, the upper section 36 may be bent or pivoted about crease line 38 so that the upper section 36 extends generally alongside the users thigh, rather than at an angle thereto.

Whilst the legs are preferably formed of aluminium, aluminium alloy or similar 3834-1.doc -7material, plastics or composite materials may be used.

C"l .,Whilst the preferred embodiment has the shell 26, loops 30 and legs 16 as 0 separate components, two or more of these may be formed integrally. Thus, for instance, the loops and shell may be formed as an integral unit attached to separate legs. Where the legs are formed of plastics or a composite material, all three sets of components may be more easily formed as an integral unit. It will be appreciated that it is not critical to the invention as to whether these C"l IND components are separate or integral.

The straps 30 are preferably folded back and sewn to themselves around one of the respective loops to permanently secure the strap to the respective loop and provided with complementary sections of hook and loop fastener material at the other, free, end so as to enable adjustment of the straps to accommodate different sizes of user legs. If desired, both ends may be provided with complementary sections of hook and loop fastener material.

The lower leg mounting 14 is similar to the upper mounting 12 and includes a lower shell 50, padding 52, loops 54 and mounting straps 56. The lower shell padding 52, loops 54 and mounting straps 56 are preferably formed of similar materials to the upper shell, loops and straps as previously described.

The lower shell 50 is positioned below the user's knee joint at the front of the leg with the straps 56 extending around the rear of the leg.

In the preferred embodiment the loops 54 are attached to the outer surface of the lower shell 50. Because the lower leg assemblies are preferably generally cylindrical rather than flat plate, the lower shell 50 and loops 54 are attached to the leg assemblies 20 by two part clamps 58a, 58b that extend around the upper tube 70 of the leg assemblies. A spacer 60 is positioned between the lower clamp 58b and the lower loop 54 to position the shell 26 inward of the leg assemblies. The lower loop 54b is sandwiched between the shell and the spacer Bolts (not shown) extend from the inner surface of the shell through bores 3834-1.doc -8- O (not shown) in the shell 50, loops 54, spacer 60 and inner clamp portion 63 to Sengage threaded bores (not shown) in the outer clamp portion 61 to clamp all of

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O these components to each other and the leg assembly The lower leg assemblies 20 are adjustable in length and each includes an upper tube 70 and a lower tube 72. The lower tube 72 is received telescopically \within the upper tube. In the preferred embodiments these tubes 70 72 are q circular in cross section. The tubes may have other cross sections, such as an C"l ND oval. Located within the upper section of the upper tube is a stop member 74.

The upper tube 70 has a series of spaced apart apertures 76 in its rear and the stop member has a spring-loaded button 78 that extends through one of the apertures to retain the stop member 74 in position. These apertures 76 are spaced at approximately 17 mm centres and allow the stop member 74 to be positioned at one of many positions within the upper tube 70. A different value for the spacing of the apertures 76 may be used.

The top end 80 of the lower tube 72 is closed, preferably by a cap 82. The bottom end 86 of the stop member 74 is preferably solid. However, if the stop member 74 is formed of a tube a cap may be used to close its bottom end 86. A spring 84 is sandwiched between the cap 82 of the lower tube 72 and the bottom 86 of the stop member 74.

The spring 84 serves to provide suspension to the leg assembly. The spring is relatively stiff provides about 1 to 3 cm of movement under the weight of a normal human. Accordingly, each spring has a spring rate of about 0.005 cm/N (200 N/cm).

When loaded the lower tube 72 bears against the spring 84. Thus by altering the position of the stop member 74 within the upper tube 70, the effective length of the leg assembly may be altered.

Referring to figure 9, the lower end of the stop member 74 has an aperture 71 3834-1.doc -9- O through which a threaded bolt 73 passes. The bolt 73 passes through an aperture in the cap 82 and secured in the upper end of the lower tube, with the O head 75 of the bolt within the stop member 74. The bolt 73 thus moves with the lower tube and slides relative to the stop member 74. Maximum separation of the upper and lower tubes is limited by the head 75 bearing against annular flange 77 of the stop member. Upwards motion of the lower tube 72 relative to Nthe stop member 74 is not limited by the bolt 73. It will be appreciated that the N bolt 73 may be screwed into the stop member 74 and slide relative to the lower tube 72.

Whilst a coiled spring 84, preferably of metal, is preferred for the device, other means of biasing the two tubes 70, 72 apart may be used. Thus, for instance, a resilient solid component formed of rubber or an elastomeric polymer may be interposed between the stop member 74 and the cap 82. An air bladder may also be used.

The lower end 88 of the upper tube 70 is provided with a bush 90 that engages the lower tube 72. The cap 82 also serves as a bush for the lower tube 72 within the upper tube 70. The cap 82 and bush 90 also provide sufficient static friction to prevent the lower tube 72 from unintended downward movement relative to the upper tube during use, whether due to its weight alone or due to the swinging action in use.

The apertures 76 are spaced at approximately 17 mm centres and so movement of the stop member 74 only provides coarse adjustment of the overall length of the leg assembly. Accordingly, the lower end 96 of the lower tube 72 includes an adjustable foot assembly 92 that provides fine adjustment of the overall length.

The foot assembly 92 includes a rod or tube 94 that is telescopically received within the lower end 96 of the lower tube 72. The lower end of the rod 94 is preferably provided with a resilient pad 98 to provide additional shock 3834-1.doc O absorption and prevent slipping. A lock nut 100 is provided to secure the rod 102 in position. The rod 96 is preferably threaded and engages with an insert O 102, having a complementary female thread, located in the inner tube 72, with Sthe lock nut 100 mounted on the rod 96 and being tightened against the end of then lower tube 72 to lock the rod 96 in position.

\The foot assembly 92 also provides a fine adjustment to allow for the weight of q the person and also to modify the weight distribution on the two sides of the IND device, if desired.

Each of the hinge assemblies 18 includes an upper flange 110, lower flange 112, spring 114, washers 116 and two part fastener 118. The free ends 120, 122 of the spring 114 are located in recesses 124 and 126 of the upper and lower flanges 110 and 112, respectively. Rotation of the flanges about fastener in either direction deflects the spring.

The upper flange 1 10 is attached to the upper leg via fasteners (not shown) passing through apertures 128 and 130. Other fastening methods may be used, such as gluing, welding etc. If desired the upper flange 110 and the upper leg 16 may be formed integrally. The lower flange includes a protrusion 132 which is received in the upper end of the upper tube 70. The protrusion is glued, riveted, welded or otherwise fastened in the upper tube.

In use the device is attached to user's thigh and lower leg. The device is adjusted so that the axes 22 of the hinges align with the general axis of rotation of the user's knee. The user is thus free to rotate their lower leg about their knee. The lower mounting 14 is mainly provided to ensure that the lower leg assemblies 20 move with the lower leg, rather than to transfer load between the lower leg and the lower leg assemblies The length of the lower leg assemblies 20 is adjusted as desired so that when walking the resilient pads 98 extend below sole of the user's footwear. It will be appreciated that the overall lengths of the two lower leg assemblies 20 will 3834-1.doc 11 probably be different. This is due to how the user's leg extends and the nature _of the damage or injury to the user's knee. Thus, for example, a person with O bowed legs will need a different configuration to a person with neutrally aligned legs.

As the user walks, jogs or runs the pads 98 contact the ground and part of the user's weight is transferred from the thigh via the upper shell 26 and straps to the upper legs 16. This is then transferred via hinges to the lower leg IND assemblies 20 and then to the ground, bypassing the knee joint. This places less Sload on the knee and so aids continued usage of the knee and/or enables recovery of the knee. The springs reduce the shock of the impact on the user's body.

The amount of weigh transferred from the thigh via the device depends on how far the pads 98 extend beyond the sole of the user's footwear. The pads may extend so that the soles never contact the ground, in which case all of the user' s weight bypasses the knee. The pads may extend so that the pads initially contact the ground before the soles but the user's weight then compresses the spring in the leg and allows the soles to bear some weight and load the knee.

The knee brace may provide some fore/aft adjustment of the contact point relative to the user's foot. This may be achieved by providing adjustable mounting of the lower leg assemblies relative to the lower shell Alternatively, or in combination with such adjustable mounting the foot 92 and/or resilient pads may be substituted with a foot that allows for fore/aft movement of the contact point. The resilient pads or rod 94 may be attached to the heels of the user's shoes on the sides of the shoes.

Whilst the preferred embodiment is substantially symmetrical this is not essential to the invention.

The use of two spring-loaded lower legs is not essential. For example, a single lower leg may extend centrally in front of the user's shin, with a U-shaped 3834-1.doc -12mounting for attachment to the two hinges on either side of the knee and a _similar U-shaped mounting with adjustable feet adjacent the user's foot.

O 0 The device need not have two hinge units. A single hinge unit may be utilised to one side of the knee. Such a single hinge unit could attach to a single lower leg as described above or to two lower legs as described with reference to the preferred embodiment.

"1 It will be appreciated that the device is relatively rigid perpendicular to the hinge axes and so provides lateral good support to the user's knee.

Whilst the preferred embodiment utilises a simple hinge for articulation of the upper and lower leg assemblies it will be appreciated that other methods of articulation may be used.

Whilst the invention has been described with reference to a knee brace the invention is not limited to a knee brace and extends to use with other joints, such as the elbow and the neck. For instance a neck brace may include a first part that attaches to the user's upper neck or head and a second part that mounts to the users shoulder region. The two parts may be articulated together to allow movement of the neck and head in certain directions, with loads transferred from the body to the upper neck and head via the brace rather than via the lower neck. Springs may be provided to control movement and reduce shock.

It will be apparent to those skilled in the art that many obvious modifications and variations may be made to the embodiments described herein without departing from the spirit or scope of the invention.

Claims (4)

1. 3834-1.doc I-13- O The claims defining the invention are as follows: 0 1. A brace for a joint including: a first mounting for attachment to a user's body on one side of the joint; O a second mounting for attachment to the user's body on the other side of a joint; O the first and second mountings are articulated together via a connection to allow desired movement of the joint or to prevent or discourage undesired movement of the joint or series of joints, or both, and at least one load transfer mechanism for connection to the user's body part on the other side of the joint for movement therewith and connected to the first mounting, wherein, in use, said load transfer mechanism transfers to the first mounting at least some of a load that, in the absence of the brace, would travel via the joint, thereby reducing the load placed on the joint.
2. 2. The brace of claim 1 wherein the load transfer mechanism includes a first portion and a second portion, said portions being movable relative to each other under load.
3. 3. The brace of claim 2 wherein the first portion includes a first component and said second portion includes a second component, first and second components telescopically joined together.
4. 4. The brace of claim 3 wherein the first portion includes a first stop member that limits the movement of the second component relative to the first component in a first direction. The brace of claim 4 wherein the first stop is movable relative to the first 3834-1.doc ID -14- component. 0 6. The brace of claim 4 or claim 5 including a second stop member to limit the movement of the second component relative to the first component in the opposite direction. 7. The brace of any one of claims 3 to 6 wherein the two components are C, biased apart. 8. The brace of claim 7 including a biasing member located between the first stop member and the second component. 9. The brace of any one of the preceding claims wherein a portion of the load transfer mechanism is mounted on the second mounting for movement therewith. The brace of any one of the preceding claims wherein the load transfer mechanism is adapted to contact an external surface and transfer load to the external surface. 11. The brace of any one of the preceding claims wherein the second portion includes a foot member connected to said second component, said foot member movable relative to the second component, whereby the effective length of the second portion is adjustable.. 12. The brace of any one of the preceding claims wherein the first and second mountings are connected together about a single axis. 13. The brace of any one of claims 1 to 11 wherein the first and second mountings are connected about a complex hinge. 14. The brace of any one of the preceding claims wherein the load transfer mechanism is connected to the first mounting via the connection. The brace of any one of claims 1 to 13 wherein the load transfer mechanism is connected to the first mounting. 3834-1.doc ND 0 16. The brace of any one of claims 1 to 13 wherein the load transfer O mechanism is connected between the first and second mountings. 17. A knee brace that includes a first mounting for attachment to the thigh of a user, a second mounting for attachment to the lower leg of a user, the first and 5 second mountings pivotably attached to each other and at least one load transfer Va Cdevice that, in use, extends to adjacent the sole of the user's foot or footwear, the ND load transfer device transferring at least part of the load that normally passes 0 through the user's knee when walking, jogging or running from the user's thigh to the ground. 18. A brace, substantially as herein described with reference to the drawings. Dated 20 October 2006 Albert Yousif By his Patent Attorneys Acumen Intellectual Property