DK2637612T3 - Orthopedic ankle devices - Google Patents

Description

DESCRIPTION

[0001] The present invention relates to ankle foot orthopaedic devices.

[0002] Figs. 1 and 2 show part of a human lower limb 10, comprising a lower part of a leg 12, a foot 14, and an ankle joint 16 therebetween. The foot comprises a hind foot 18, a mid foot 20 and a fore foot 40. Figs 1 and 2 also show the anatomical planes comprising the frontal plane 22, the median sagittal plane 24 and the transverse plane 36.

[0003] In this specification, standard anatomical terms are used with, for the avoidance of doubt, the meanings as set out below and by reference to Figs. 1 and 2:

[0004] The dominant motion of the foot relative to the lower leg as required for walking and running occur through what is commonly described as the ankle joint. The ankle joint comprises two major joints each with a dominant axis of motion. The joint formed between the lower surface of the tibia and upper surface of the talus is known as the tibio-talar joint. The ti bio-talar joint enables the foot to be raised and lowered or dorsiflexed and plantaflexed using medical terminology. The joint formed by the lower surface of the talus and the upper surface of the calcaneous enables the foot to be turned outwards or inwards in a rolling motion known as eversion and inversion. Anatomically correct motion of the hind foot is complex as it involves motions that are the combined motions of the motions of the tibio-talar and sub-talar joints.

[0005] People with disabling foot conditions, whether congenital, trauma-related or idiopathic often benefit from therapies using orthopaedic devices or braces. Such braces typically hold the foot in a prescribed position, allow limited movement of the foot within defined constraints or bias the movement of the foot in a particular way.

[0006] An example of a conventional ankle foot orthopaedic device can be found in German patent DE29909113U1, which discloses an ankle foot orthopaedic device including a first part for association with a leg engaging item, a second part for association with a foot engaging item, a connector for connecting the first part to the second part, the connector including a first adjuster, which, in an adjustment condition, permits a first adjustment relative movement of the first part and the second part around a first device axis of rotation. However, the adjustment movement does not correspond with any of the anatomical axes of rotation of the ankle joint.

[0007] This invention overcomes substantial limitations in current bracing solutions.

[0008] Current bracing solutions cannot combine the motions of both the sub-talar and tibio talar joints meaning that in use they cannot support dynamic corrective therapies involving both sub-talar and tibio-talar joints. Current dynamic braces do not enforce anatomically correct motion of both joints.

[0009] Current bracing solutions requiring to brace or to bias the sub-talar joint achieve this only through the inclusion of a connecting rigid bar between each of the user's feet or through the use of an attachment to the leg which extends well above the knee and is worn with the user's knee in a fixed and substantially bent position. Such braces are inconvenient because the user cannot walk in them and suffer from other inherent disadvantages.

[0010] Current general purpose braces to address conditions such as foot drop and many others do not provide dynamic therapy for both tibio-talar and sub-talar joints. Such braces cannot support and reinforce anatomically correct ambulation.

[0011] This invention overcomes fundamental limitations of current bracing solutions and makes new improved therapies possible for people affected by a myriad of disabling conditions of the foot. The inventor has precisely understood the dominant anatomical motions of both tibio-talar and sub-talar joints and realised how to model these in a single wearable device. Of particular significance is the inventor's realisation of the significance of the surprising nature of the sub-talar joint. The invention exploits the geometry of this motion to create a dynamic orthopaedic device that can brace or bias the sub-talar joint without the need for connecting bars or a fixed and bent knee.

[0012] According to a first aspect of the present invention, there is provided an ankle foot orthopaedic device as defined in claim 1 of the claims.

[0013] According to a second aspect of the present invention, there is provided a splint for aiding immobilisation of a body part as defined in claim 14 of the claims.

[0014] Other features of the invention are as defined in the dependent claims.

[0015] The device models and controls anatomically correct movement of the user's foot and ankle with respect to the leg and enabling the user's sub-talar joint to be braced or biased in a position where the foot is either abducted or adducted and thereby enabling the user's tibio-talar joint to be braced or biased in a position of dorsiflexion or plantaflexion.

[0016] The device is able to brace or bias the user's foot in a position of abduction or adduction through the axis of rotation of the sub-talar joint without the need for either a connecting bar between each leg or a leg engaging item that extends above the knee joint of the leg and which requires the leg to be held in a fixed position substantially bent at the knee.

[0017] Embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:-

Fig. 1 is a perspective lateral view of a human right foot showing the bones of the ankle joint and hind foot and the anatomical planes;

Fig. 2 is a perspective rear and lateral view of the foot and planes of Fig. 1;

Figs. 3A to 3D are simplified diagrammatic cross sectional views of a human right foot through the tibio-talar and sub-talar joints, Fig 3A being a front (anterior) view, Fig 3B being an exterior side (lateral) view, Fig 3C being a plan (dorsal) view at the level of the tibio-talar joint as indicated by the line C-C in Fig 3A and Fig 3D being a plan (dorsal) view at the level of the sub-talar joint as indicated by the line D-D in Fig 3A;

Fig. 4 is a perspective lateral side view of a first ankle foot orthopaedic device;

Figs. 4A, 4B and 4C are simplified plan views of a right leg and foot illustrating how a leg attachment and first adjusters of the device of Fig 4 interact to create a device capable of adducting or abducting the foot without the need for a connecting bar between each foot or for the user's knee to be held in a fixed and bent condition;

Fig 4D is a side view of the leg, foot and device of Figs 4A, 4B and 4C;

Fig. 5 is a plan view of the orthopaedic device of Fig. 4;

Fig. 6 is a lateral side view of the orthopaedic device of Figs. 4 and 5;

Fig. 7 is a rear view of the orthopaedic device of Figs. 4 to 6;

Fig. 8 is a lateral side view of a detail as indicated by the reference VIII in Fig 6;

Fig. 9 is a view of the detail shown in Fig 8, partially disassembled;

Fig. 10 is a similar view to that of Fig. 8, of a detail of a second orthopaedic device;

Fig. 11 is a rear view of a third orthopaedic device not according to the invention;

Fig. 12 is a side view of the orthopaedic device of Fig. 11;

Fig. 13 is a perspective medial side view of a fourth orthopaedic device;

Fig. 14 is a lateral side view of the orthopaedic device of Fig. 13;

Fig. 15 is a rear view of a fifth orthopaedic device;

Fig. 16 is a rear view of a sixth orthopaedic device;

Fig. 17 is a perspective lateral side view of the orthopaedic device of Fig. 16; and Fig. 18 is a rear view of a seventh orthopaedic device.

[0018] Save for Figs 4A, 4B, 4C and 4D the devices shown are all for the left lower limb. The skilled person will appreciate that devices for the right lower limb will be symmetrical.

[0019] The movement of the foot 14 relative to the leg 12 is relatively complex. The surfaces which comprise the tibio-talar and sub-talar joints permit three dimensional movement which has been found to be difficult to describe, analyse and model adequately. The movement can be irregular and can vary between individuals. Thus, for example, the tibio-talar joint has been described in various different studies as having a helical axis; as having a hinge axis; and as having multiple axes which are different during plantarflexion and dorsiflexion.

[0020] The applicant has realised that for the purposes of providing an orthopaedic device for the treatment of various conditions of the ankle and foot, the movement of the foot 15 relative to the leg 12 can be simplified and yet accurately modelled as shown in Figs 3A to 3D.

[0021] In this analysis and modelling, the movement at the sub-talar joint 42 is simplified as being rotational around a sub-talar pivot axis 50 which extends posterior plantar to anterior dorsal in the sagittal plane 34, subtending a first anatomical angle 52 to the transverse plane 36 in the sagittal plane 34, and extends posterior lateral to anterior medial in the transverse plane 36, subtending a second anatomical angle 54 to the sagittal plane 34 in the transverse plane 36.

[0022] With the foot 14 in the neutral condition, the first anatomical angle 52 can lie in the range 32° to 52°, and more frequently lies in the range 37° to 47°, and usually is approximately 42°. In the neutral condition, the second anatomical angle can lie in the range 8° to 24°, and more frequently lies in the range 12° to 20°, and usually is approximately 16°.

[0023] In this analysis and modelling, the movement at the tibio-talar joint 32 is simplified as being rotational around a tibio-talar pivot axis 44 which extends medial anterior to lateral posterior in the transverse plane 36, subtending a third anatomical angle 46 to the frontal plane 22 in the transverse plane 36, and extends medial dorsal to lateral plantar in the frontal plane 22, subtending a fourth anatomical angle 48 to the transverse plane 36 in the frontal plane 22.

[0024] With the foot 14 in the neutral condition as shown in Figs 3Ato 3D, the third anatomical angle 46 can lie in the range 15° to 35°, and more frequently lies in the range 20° to 30°, and usually is approximately 25°. In the neutral condition, the fourth anatomical angle 48 can lie in the range 3° to 13°, and more frequently lies in the range 6° to 10°, and usually is approximately 8°.

[0025] Broadly and approximately, the anatomical movement at the tibio-talar joint 32 can be regarded as plantarflexion or dorsiflexion, and the anatomical movement at the sub-talar joint 42 can be regarded as a combination in equal parts of abduction and eversion or a combination in equal parts of adduction and inversion.

[0026] Figs 4 to 9 show an ankle foot orthopaedic device 56, the design of which is based on the analysis and modelling described above.

[0027] The device 56 includes a first part in the form of a first connecting arm 58 for association with a leg engaging item 72, a second part in the form of a shoe engaging item 60 for association with a foot engaging item 86 and a connector 62 for connecting the first connecting arm 58 to the shoe engaging item 60. The connector 62 includes a first adjuster 66, which, in an adjustment condition, permits a first adjustment relative movement of the first connecting arm 58 and the shoe engaging item 60 around a first device axis 150 of rotation. The connector 62 includes a second adjuster 64, which, in an adjustment condition, permits a second adjustment relative movement of the first connecting arm 58 and the shoe engaging item 60 around a second device axis 144 of rotation. In use in a fitted condition in which the device 56 is fitted to a user's leg and foot, the first device axis 150 substantially corresponds with a dominant anatomical axis of rotation of the sub talar joint 50 and the second device axis 144 substantially corresponds with a dominant anatomical axis 44 of rotation of the tibio-talarjoint.

[0028] By the term "foot engaging item" the skilled person will understand that the item concerned could engage a bare foot, a clothed foot, or an item of footwear such as a shoe or a boot. Similarly, by the term "shoe engaging item" the skilled person will understand that the item concerned could engage any suitable item of footwear such as a footplate, a shoe or a boot.

[0029] The connector 62 includes a second connecting arm 68 which extends between and spaces apart the first and second adjusters 66, 64.

[0030] In the adjustment condition the first adjuster 66 permits a first rotational adjustment movement around a first device axis of rotation 150 of the second connecting arm 68 relative to the shoe engaging item 60. In the adjustment condition the second adjuster 64 permits a second rotational adjustment movement around a second device axis of rotation 144 of the second connecting arm 68 relative to the first connecting arm 58.

[0031] The first connecting arm 58 and the second connecting arm 68 need to be formed to correctly position the first adjuster 66 and second adjuster 64 with respect to the user and to achieve the correct alignment of the first device axis of rotation 150 and the second device axis of rotation 144. Both connecting arms need to be manufactured from a rigid, but lightweight material such as 30% glass filled nylon. Both adjusters need to create a rigid yet smooth running axis of motion capable of withstanding significant torsion forces required to brace or bias the users foot. Both adjusters might be made from a steel spigot running in a nylon sleeve. The device may be produced from any suitable materials providing there is sufficient rigidity and the adjusters run freely under load.

[0032] Referring specifically to Figs 5 to 7:

The first device axis 150 of rotation of the first adjuster 66 subtends a first device angle 152 to the transverse plane 36 in the sagittal plane 34 extending posterior plantar to anterior dorsal, and subtends a second device angle 154 to the sagittal plane 34 in the transverse plane 36 extending posterior lateral to anterior medial.

[0033] In one example, in the neutral condition, the first device angle 152 could be 42°. In other examples, in the neutral condition, the first device angle 152 could lie in the range 32° to 52°, and more desirably could lie in the range 37° to 47°.

[0034] In one example, in the neutral condition, the second device angle 154 could be 16°. In other examples, in the neutral condition, the second device angle 154 could lie in the range 8° to 24°, and more desirably could lie in the range 12° to 20°.

[0035] The second device axis 144 of rotation of the second adjuster 64 subtends a third device angle 146 to the frontal plane 22 in the transverse plane 36 extending medial anterior to lateral posterior, and subtends a fourth device angle 148 to the transverse plane 36 in the frontal plane 22 extending medial dorsal to lateral plantar.

[0036] In one example, in the neutral condition, the third device angle 146 could be 25°. In other examples, the third device angle 146 could lie in the range 15° to 35°, and more desirably could lie in the range 20° to 30°.

[0037] In one example, in the neutral condition, the fourth device angle 148 could be 8°. In other examples, the fourth device angle 148 could lie in the range 3° to 13°, and more desirably could lie in the range 6° to 10°.

[0038] In the example shown in Figs 4 to 9, the foot engaging item 86 is in the form of a specialised shoe, in which a part of the foot 14 is receivable in use. The shoe 86 comprises an outer relatively rigid shoe member 88 and an inner, relatively flexible cushion or pad member 90.

[0039] The shoe engaging item 60 may attach directly to a suitable shoe or to some form of shoe mounting 92 for mounting the shoe engaging item 60 and the shoe 86 together. The mounting could permit linear adjustment of the shoe 86 relative to the shoe engaging item 60.

[0040] Figs 8 and 9 illustrate a second adjuster 64. The second adjuster 64 is formed by the union of a disc-like adjuster member 94 attached or moulded to the second connecting arm 68 from which an axle 96 extends and a cap-like adjuster member 95 which has a central hole to form a bearing contact with the axle 96. When assembled the axle 96 of the disc-like adjuster member 94 fits into the hole of the cap-like adjuster member 95 to achieve an adjustment movement in the required axis of motion. The second adjuster 64 must be manufactured to provide a movement that is both smooth running and rigid even when subject to bracing loads in use.

[0041] Pegs 98 project from the disc-like adjuster member 94. The second adjuster 64 includes second biasing means comprising a second bias member 100 in the form of a torsion spring engages one of the pegs 98 and a peg or hole in located in the internal side of the cap-like adjuster member 95. In one example, each adjuster member 94 has six equispaced pegs 98 to enable adjustment of the pre-loaded torsion forces applied by the spring in the neutral position. The second bias member 100 and pre-loaded torsion mean that the second adjuster exerts a force which either dorsi-flexes or plantar-flexes the shoe engaging 60 item relative to the leg engaging item 72 depending on the direction of the torsion force exerted by the bias member 100.

[0042] The configuration of the first adjuster 66 is similar to that of the second adjuster 64 except that the disc-like adjuster member 94 is attached to the shoe engaging item 60 and the cap-like adjuster member 95 is attached or moulded to the second connecting arm 68. The first adjuster 66 includes first biasing means including a first bias member 100. For the first adjuster 66 the bias member 100 and pre-loaded torsion mean that the first adjuster exerts a force which either abducts or adducts the shoe engaging item 60 relative to the leg engaging item 72 depending on the direction of the torsion force exerted by the bias member 100.

[0043] Each adjuster 64, 66 includes a restrictor 102 which includes a tab 104 which projects from, or forms part of, part of the periphery of one of the adjuster members 94 and defines a plurality of limit holes 106. The restrictor 102 includes a pair of limit stops 108 in the form of screws which are located in two of the limit holes 106. The limit stops 108 are removable and repositionable. The restrictor 102 includes a lug 110 which projects from the other of the adjustment members 94 and locates between the limit stops 108. In use, the engagement of the lug 110 with the limit stops 108 limits the respective adjustment movement.

[0044] The restrictors 102, and in particular, the positions of the limit stops 108 in the limit holes 106, determine the maximum extent of relative movement of the first connecting arm 58 and second connecting arm 68 for the second adjuster 64 and the second connecting arm 68 and shoe engaging item 60 for the first adjuster 66. In one example, the tab 104 defines twenty four limit holes 106, which are at 5° intervals. In one example, the restrictor 102 of the first adjuster 64 could be arranged to permit up to 90° of plantarflexion and up to 30° of dorsiflexion. In one example, the restrictor 102 of the second adjuster 66 could be arranged to permit up to 60° of inversion/adduction and 60° of eversion/abduction.

[0045] In the example shown in Figs 4 to 9, the device 56 includes the leg engaging item 72 into which a part of the leg 12 is receivable in use. The leg engaging item 72 comprises an outer relatively rigid member 74 and an inner relatively soft and flexible member 76 to provide a comfortable contact with the user's leg.

[0046] In use it is important to position the leg engaging item such that it correctly acts as a foot brace capable of simultaneously bracing or biasing both major joints of the foot. This means the sub-talar joint 42 is rotated such that the foot is either adducted or abducted and the tibio-talar joint 32 is rotated such that the foot is either dorsiflexed or plantaflexed.

[0047] Fig 4 illustrates a leg attachment 72 extending further forward on the medial side 116 than the outer lateral side 118. The example shown in Fig 4 has the first connecting arm 58 at the rear of the device and extends the medial side 116 of the leg attachment 72, but a number of alternative configurations will achieve the required function provided that the first and second connecting arms 58, 62 and the first and second adjusters 66, 64 are sufficiently rigid and permit rotational movement only along the axes previously described.

[0048] An important feature of the device 56 is that it enables the sub-talar joint to be braced and or biased without the need for a connecting bar between the left and right feet or for a leg attachment extending above the knee and for the user's knee to be held in a substantially bent condition. Figures 4A, 4B, 4C and 4D illustrate how this is achieved and example configurations of the first connecting arm 58 and leg attachment 72.

[0049] Fig 4A is a simplified plan view of the device 56 in use with a suitable shoe 86, the shoe 86 is closely fitting yet allows full and free movement of both sub-talar and tibio-talar joints. Providing the leg 12 is stabilised movement of the shoe 86 will correspond to movement of the foot 14. The arrangement of the first and second adjusters 66, 64 and first and second connecting arms 58, 68 means the foot may move only according to the dominant anatomical axes of the sub-talar joint 50 and tibio-talar joint 44.

[0050] In Fig 4A the leg 12 is sectioned along the axis E-E as illustrated in Fig 4D. Fig 4A illustrates a right foot. The first connecting arm 58 is positioned laterally. In this example the first adjuster 66 is subject to a torsion force due to the effect of the bias member 100. The effect of the torsion force is to subject the first connecting arm 58 to a force F-|. The first connecting arm 58 is attached to straps 112, which in turn are connected to the leg attachment 72. The force F-| is transferred to the leg attachment such that it exerts a first bracing force F2 on the leg 12. The position of the force F2 is further illustrated in Fig 4D where it can be seen that a turning moment M is applied through the axis of the sub-talar joint 50. Since the leg attachment 72 cannot move and acts as a brace stabilising the leg 12 relative to the foot 14, the net effect is that the shoe 86 and hence the foot 14 is abducted about the axis of the sub-talar joint 50.

[0051] The extent of abduction achieved is determined by a number of factors including the condition of the user, the strength of the bias member 100 and the position of the restrictors 102. For clarity the second adjuster 64 is not shown in Fig 4A, but a skilled practitioner will realise that since the leg attachment 72 extends beyond the rear centreline of the leg the foot can also be dorsiflexed about the anatomical axis of the tibio-talar joint 44.

[0052] An advantage of the configuration illustrated at in Fig 4A is that the leg attachment 72 acts like a sling that is being pulled from either side by the first connecting arm 58 and the straps 112. The leg attachment may therefore be produced from relatively soft and flexible materials making it more comfortable for the user. The skilled practitioner will also realise that the configuration may be reversed to adduct and or plantaflexthe foot.

[0053] Fig 4B is a simplified plan view of the device 56 in use with a suitable shoe 86, the shoe 86 is closely fitting yet allows full and free movement of both sub-talar and tibio-talar joints. Providing the leg 12 is stabilised movement of the shoe 86 wll correspond to movement of the foot 14. The arrangement of the first and second adjusters 66, 64 and first and second connecting arms 58, 62 means the foot may move only according to the dominant anatomical axes of the sub-talar joint 50 and tibio-talar joint 44.

[0054] In Fig 4B the leg 12 is sectioned along the axis E-E as illustrated in Fig 4D. Fig 4B illustrates a right foot. The first connecting arm 58 is positioned medially. In this example the first adjuster 66 is subject to a torsion force due to the effect of the bias member 100. The effect of the torsion force is to subject the first connecting arm 58 to a force F. The force F is transferred to the leg attachment 72 such that it exerts a first bracing force F on the leg 12.

[0055] The position of the force F is further illustrated in Fig 4D where it can be seen that a turning moment M is applied through the axis of the sub-talar joint 50. Since the leg attachment 72 cannot move and acts as a brace stabilising the leg 12 relative to the foot 14, the net effect is that the shoe 86 and hence the foot 14 is abducted about the axis of the sub-talar joint 50.

[0056] The extent of abduction achieved is determined by a number of factors including the condition of the user, the strength of the bias member 100 and the position of the restrictors 102. For clarity the second adjuster 64 is not shown in Fig 4B, but a skilled practitioner will realise that since the leg attachment 72 extends beyond the rear centreline of the leg the foot can also be dorsiflexed about the anatomical axis of the tibio-talar joint 44.

[0057] An advantage of the configuration illustrated in Fig 4B is that the leg attachment 72 can be relatively small providing that is made from a relatively rigid material. The skilled practitioner wll also realise that the configuration may be reversed to adduct and or plantaflexthe foot.

[0058] Fig 4C is a simplified plan view of the device 56 in use wth a suitable shoe 86, the shoe 86 is closely fitting yet allows full and free movement of both sub-talar and tibio-talar joints. Providing the leg 12 is stabilised movement of the shoe 86 wll correspond to movement of the foot 14. The arrangement of the first and second adjusters 66, 64 and first and second connecting arms 58, 62 means the foot may move only according to the dominant anatomical axes of the sub-talar joint 50 and tibio-talar joint 44.

[0059] In Fig 4C the leg 12 is sectioned along the axis E-E as illustrated in Fig 4d. Fig 4c illustrates a right foot. The first connecting arm 58 is positioned posteriorly. In this example the first adjuster 66 is subject to a torsion force due to the effect of the bias member 100. The effect of the torsion force is to subject the first connecting arm 58 to a bracing force Fy The first connecting arm 58 is attached to a rigid leg attachment 72. The force Fi is transferred through rigid the leg attachment 72 such that it exerts a first bracing force F2 on the leg 12.

[0060] The position of the force F2 is further illustrated in Fig 4D where it can be seen that a turning moment M is applied through the axis of the sub-talar joint 50. Since the leg attachment 72 cannot move and acts as a brace stabilising the leg 12 relative to the foot 14, the net effect is that the shoe 86 and hence the foot 14 is abducted about the axis of the sub-talar joint 50.

[0061] The extent of abduction achieved is determined by a number of factors including the condition of the user, the strength of the bias member 100 and the position of the restrictors 102. For clarity the second adjuster 64 is not shown in Fig 4C, but a skilled practitioner will realise that since the leg attachment 72 extends beyond the rear centreline of the leg the foot can also be dorsiflexed about the anatomical axis of the tibio-talar joint 44.

[0062] An advantage of the configuration illustrated at Fig. 4C is that the first connecting arm 58 is positioned conveniently to the rear of the user's leg. The skilled practitioner will also realise that the configuration may be reversed to adduct and or plantaflex the foot.

[0063] Similarly, the second bias member 100 of the second adjuster 64 provides a second bracing force which is a torsional force around the second device axis 144. Thus, the first adjuster 66 includes first biasing means for providing a first bracing force and the second adjuster includes second biasing means for providing a second bracing force which, in use, together and simultaneously brace the user's foot in any one or any suitable combination of a neutral position, an abducted position, an adducted position, a dorsiflexed position and/or a plantarflexed position.

[0064] The device 56 may include an adjustable leg attachment mounting 78 for mounting the first connecting arm 58 and the leg attachment 72 together. The adjustable leg attachment mounting 78 comprises a plurality of holes 80 defined by the first connecting arm 58. The leg attachment 72 slidably locates within a channel 82 defined by the relatively rigid outer member 74 of the leg attachment 72 and is held in a selected position by a fastener 84 such as a screw, bolt or rivet which extends through one of the holes 80 into a threaded hole (not shown) defined by the relatively rigid outer member 74 of the leg attachment 72. The adjustable leg attachment mounting 78 permits linear adjustment of the leg attachment 72 relative to the first connecting arm 58.

[0065] The device 56 includes a plurality of pairs of securing straps 112 which extend from the brace part 72. The securing straps 112 could be in any convenient form, for example, in the form of laces or, as shown in Fig 4, in the form of straps. The device 56 further includes fasteners 114 to fasten the respective straps 112 together. The fasteners 114 could be in any convenient form, for example, in the form of buckles, laces or, as shown in Fig 4, hook and loop fastenings. The straps 112 and fasteners 114 are shown only in Fig 4 for the sake of ease of interpretation of the drawings, but it will be understood would actually be present in the other views of the embodiment, and in other similar embodiments. It will be further understood that typically the shoe 86 would require additional straps, especially in the hindfoot and midfoot area to secure the heel to the shoe in the correct position. For clarity the shoe 86 in Fig 4 illustrates just a single strap. In other examples, the number of securing members 112 and the means of attachment of the securing members to the brace part 72 and the shoe 86 could be different.

[0066] In use, the leg attachment 72, shoe engaging item 60, first connecting arm 58, second connecting arm 68 and shoe 86 could be provided of different sizes. Prior to fitting, measurements could be taken of the leg 12 and foot 14 and appropriately sized parts selected. In one example, the parts are provided separately and assembled for fitting. In another example, the device 56 is provided pre-assembled in a number of different size combinations, and the most suitable combination selected. The orthopaedic device 56 is fitted to a lower limb 10 of a user so that a leg 12 is received by the brace part 72 and a foot 14 is received by the shoe 86. The securing members 112 are fastened together. The adjustable leg attachment mounting 78 and the shoe mounting 92 can be adjusted as described above.

[0067] Initially, during fitting in the adjustment condition, the limit stops 108 could be removed for ease of adjustment, or could be positioned in an approximate position or positioned to hold the device 56 in a neutral condition with no abduction or adduction and no dorsiflexion of plantaflexion. During the fitting, the foot 14 may be manipulated to a new position, and the limit stops 108 set to brace the foot in a restricted condition. In a restricted condition the relative movement between first connecting arm 58 and the second connecting arm 68 and the second connecting arm 68 and shoe engaging item 60 is restricted relative to the movement permitted in the adjustment condition. The restricted condition may allow no movement of the tibio-talar and sub-talar joints or more typically will allow some movement permitting the user to exercise against the torsion forces exerted by the bias members 100.

[0068] In cases where the user is suffering from varus, adduction and equinus the device 56 will typically be configured to limit varus, adduction and plantaflexion and to brace or bias the foot into a position of valgus, abduction and dorsiflexion as illustrated in Figures 4a to 4d. For other conditions the device may be configured to brace or bias the foot in the opposite direction.

[0069] The device 56 simultaneously corresponds with the anatomical movements of both major joints of the foot. Because the device 56 can abduct (and adduct if necessary) the foot without the need for a fixed bent knee or a rigid connecting bar between both feet it enables for the first time a dynamic brace that offers improved and more acceptable therapies for a host of foot conditions. The device 56 can be used with any suitable shoe providing it can be firmly attached to the shoe engaging item 60.

[0070] Figs 10 to 18 show other embodiments of the invention, many features of wlnich are similar to those already described in relation to the embodiment of Figs 4 to 9. Therefore, for the sake of brevity, the following embodiments will only be described in so far as they differ from the embodiment already described. Where features are the same or similar, the same reference numerals have been used and the features will not be described again. It should be also assumed, unless stated otherwise, that the methods of use for the following embodiments are similar to that described for the above embodiment.

[0071] Fig 10 shows a detail of a second orthopaedic device 156, in which the second adjuster 164 includes an indicator 120, including a plurality of markings 122 which could indicate, for example, angles of rotation from the neutral. The first adjuster (not shown in Fig 10) could also include an indicator 120. In the case of the second adjuster 164, the angles indicated could relate primarily to the angle of dorsiflexion or plantarflexion. In the case of the second adjuster, the angles indicated could relate primarily to the angle of inversion/adduction or eversion/abduction.

[0072] The indicator 120 permits reproducibility of setting of positions, and also enables the user and practitioner to easily monitor progress over a course of treatment, which gives encouragement and motivation. The indicator 120 can also help monitor the extent of movement during exercise as the user moves against the bias of the springs 100, again providing encouragement and motivation.

[0073] Figs 11 and 12 show a third orthopaedic device 356 not according to the invention, the device 356 including a leg engaging item 72, a first connecting arm 58 for association with a leg engaging item 72, and a shoe engaging item 60 for association with a first connecting arm 58 and shoe 86. This device has just one adjuster 66 which corresponds to the first adjuster 66 of the first embodiment. The third orthopaedic device 356 thus permits adjustment movement only about the first device axis of rotation 150, which in use in the fitted condition corresponds to the sub-talar pivot axis 50. This device 356 could be used, for example, in cases where therapy involving only movement of the foot 14 about the sub-talar pivot axis 50 is required.

[0074] Figs 13 and 14 show a fourth orthopaedic device 556 including a leg engaging item 572, a first connecting arm 58 for association with a leg engaging item 572 and a second connecting arm 68, a second connecting arm 68 for association with a first connecting arm 58 and foot engaging item 586 including a pair of spaced adjusters 564, 566, comprising a second adjuster 564 which, in the adjustment condition, permits a second rotational adjustment movement around a second device axis of rotation 144 of the first connecting arm 58, relative to the second connecting arm 68, and a first adjuster 566, which, in the adjustment condition, permits a first rotational adjustment movement around a first device axis of rotation 150 of the second connecting arm 68 relative to the foot engaging item 586.

[0075] In this example, the leg engaging item 572 and the foot engaging item 586 are somewhat simpler than in the first embodiment, the leg engaging item 572 and foot engaging item being made of a relatively rigid, but malleable material. As with previous embodiments the first and second connecting arms 58, 62 and adjusters 566, 564 are made of a light, but rigid material. The adjusters 564, 566 are also somewhat simpler than previously described, and could, in one example, comprise a ratchet mechanism 126 which, for each adjuster, permits adjustment in one direction only.

[0076] Treatment of certain conditions of the foot especially congenital conditions in babies and young children may necessitate encasement of the lower limb 10 in a cast to immobilise it in a prescribed state of abduction or adduction and dorsiflexion or plantaflexion. It can be difficult to apply the cast while maintaining the foot 14 in the desired position, and often requires the attention of several experienced medical practitioners. Moreover, plaster casts can be prone to slippage if not perfectly formed. For this embodiment, in use, the foot is located on the foot engaging item 586 and leg engaging item 572 positioned against the lower leg. The foot is then manipulated into the desired position. The leg and foot engaging items 572 and 586 are moulded as required and then foot is manipulated into position. The relatively rigid connecting arms and adjusters assist with the manipulation process and the ratchet mechanisms assist with maintaining the desired manipulated position whilst bandage and casts are applied.

[0077] Using the fourth orthopaedic device 556 of the invention ensures that the correct position is maintained while the plaster is applied and reduces the risk of cast slippage thereby improving treatment efficacy and patient comfort. Using the fourth orthopaedic device 556 as a splint enables plaster casting to be undertaken more consistently by less experienced practitioners. The ratchet mechanism 126 makes adjustment simple and quick. The fourth orthopaedic device 556 thus provides an adjustable, disposable splint which aids the casting of the foot and leg to hold the sub-talar and tibio-talar joints is precisely manipulated condition.

[0078] Fig. 15 shows a fifth orthopaedic device 656 including a leg engaging item 72, a first connecting arm 58 for association with a leg engaging item 72 and a second connecting arm 68, a second connecting arm 68 for association with a first connecting arm 58 and a shoe engaging item 60 (not shown in Fig 15) and a pair of spaced adjusters 664, 666, comprising a second adjuster 664 which, in the adjustment condition, permits a second rotational adjustment movement around a second device axis of rotation 144 of the first connecting arm 58 relative to the second connecting arm 68 and a first adjuster 666, which, in the adjustment condition, permits a first rotational adjustment movement around a first device axis of rotation 150 of second connecting arm 68 relative to the shoe engaging item 60.

[0079] In this example, the adjusters 664, 666 are somewhat simpler than previously described, and could, in one example, each comprise a fastener 628 which forms the respective pivot axis 144, 150. The fastener 628 could be in the form of a bolt or screw, which can be loosened or tightened to move the respective adjuster 664, 666 to the adjustment condition or the restricted condition respectively. In the restricted condition, the respective adjuster 664, 666 is substantially fixed in position.

[0080] Figs. 16 and 17 show an sixth orthopaedic device 756 including a leg engaging item 72, a first connecting arm 58 for association with a leg engaging item 72 and a second connecting arm 68, a second connecting arm 68 for association with a first connecting arm 58 and a shoe engaging item 60 (not shown in Figs 16 and 17) and a pair of spaced adjusters 64, 66, comprising a second adjuster 64 which, in the adjustment condition, permits a second rotational adjustment movement around a second device axis of rotation 144 of the first connecting arm 58 relative to the second connecting arm 68 and a first adjuster 66, which, in the adjustment condition, permits a first rotational adjustment movement around a first device axis of rotation 150 of second connecting arm 68 relative to the shoe engaging item 60.

[0081] In this example, the device 756 is similar to the first device embodiment 56 except that the second connecting arm 68 extends outwardly laterally from the first adjuster 66 to the second adjuster 64, which is in a lateral position. In this position, advantageously, walking could be easier for the user as the first adjusters 64 of the two devices 756 on the two lower limbs do not clash or obstruct.

[0082] Fig. 18 shows a seventh orthopaedic device 856 including a leg engaging item 72, a first connecting arm 58 for association with a leg engaging item 72 and a second connecting arm 68, a second connecting arm 68 for association with a first connecting arm 58 and a shoe engaging item 60 (not shown in Fig 18) and three spaced adjusters 64, 66, comprising a pair of second adjusters 64 which, in the adjustment condition, permits a second rotational adjustment movement around a second device axis of rotation 144 of the first connecting arm 58 relative to the second connecting arm 68 and a first adjuster 66, which, in the adjustment condition, permits a first rotational adjustment movement around a first device axis of rotation 150 of second connecting arm 68 relative to the shoe engaging item 60.

[0083] One of the pair of spaced second adjusters 64 is positioned on the medial side and the other is positioned on the lateral side. The second connecting arm 68 includes a spacer member 68 which extends medially from the second adjuster 66 to the medial second adjuster 64 and another spacer member 68 which extends laterally from the first adjuster 66 to the lateral second adjuster 64. The pair of second adjusters 64 provides additional strength to the device 856.

[0084] Various other modifications could be made without departing from the scope of the invention. The orthopaedic device and the various components thereof could be of any suitable size and shape, and could be formed of any suitable material(s). The adjusters could be provided in any suitable way, and could be different to those described. The biasing could be provided in a different way. For example, elastic straps or bands could provide the biasing.

[0085] Any of the features of any of the embodiments shown or described could be combined in any suitable way, within the scope of the overall disclosure of this document.

[0086] There is thus provided an orthopaedic device which simultaneously corresponds with the anatomical movements of both major joints of the foot. The device can abduct (and adduct if necessary) the foot without the need for a fixed bent knee or a rigid connecting bar between both feet. It enables for the first time a dynamic brace that offers improved and more acceptable therapies for a host of foot conditions. Many of the problems associated with conventional orthopaedic devices have thus been overcome.

[0087] Compared with prior art foot abduction (or adduction) braces based on the connecting bar concept the device enables the user to walk and run normally and thus can be used for daytime as well as night-time therapy; functionality is not compromised by rotation of the hips and knees; the device does not stress hips and knees; the device can be used unilaterally; the device is less obtrusive and more acceptable to parents and patients; the device enables more precise therapy and measurement of progress; the device can simultaneously provide therapy to both the sub-talar and tibio-talar joints.

[0088] Compared with prior art foot abduction (or adduction) braces based on the fixed bent knee concept the device enables the user to walk and run normally and thus can be used for daytime as well as night-time therapy; the device enables the leg to move and for muscles to be developed or maintained and does not compromise muscle development; the device is less obtrusive and more acceptable to parents and patients; the device enables more precise therapy and measurement of progress; the device can simultaneously provide therapy to both the sub-talar and tibio-talar joints.

[0089] Compared with prior art foot drop braces and other general purpose Ankle Foot Orthoses (AFOs) the device enables the user to walk and run with an improved and more normal gait as it simultaneously supports anatomically correct motion of tibio-talar and sub-talar joints; the device can simultaneously provide therapy to both the sub-talar and tibio-talar joints.

REFERENCES CITED IN THE DESCRIPTION

This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description • DE29909113U1 (0086]

Claims (14)

An orthopedic foot joint device (56, 156, 556, 656, 756, 856), comprising a first portion (58) for attaching a leg engaging member (72), a second portion (60) for attaching a foot engagement member (86). , a connecting piece (62) connecting the first part to the second part, comprising a first adjusting device (66, 566, 666) which, in an adjustment state, allows a first relative adjustment movement of the first part and the second part about a first device rotation axis (150), characterized in that the connector comprises a second adjustment device (64, 564, 664) which, in an adjustment state, allows a second relative adjustment movement of the first part and the second part about a second device rotation axis (144), first device axis, in use and in a mounted state in which the device is attached to a user's leg and foot, substantially corresponds to a predominant anatomical axis of rotation fo r articulatio subtalaris (50), and the second device axis substantially corresponds to a predominant anatomical axis of rotation for articulatio tibialis (44). Device according to claim 1, in which the first and second device axes are substantially aligned along the articulatio subtalaris axis and the articulatio ti-bialis axis, respectively. Device according to claim 1 or 2, wherein the first adjusting device comprises first biasing means (100) for providing a first supporting force for supporting a user's articulatio subtalaris in an abused, neutral or induced position during use. Device according to claim 3, wherein the first supporting force is a torsional force. Device according to claim 3 or 4, wherein the first biasing means comprises a first biasing element (100). Device according to any one of the preceding claims, wherein the second adjusting device comprises other biasing means (100) for providing a different supporting force for using a support's articulatio tibialis in a dorsal flexed, neutral or plantar flexed position. Device according to claim 6, wherein the second supporting force is a torsional force. Device according to claim 6 or 7, wherein the second biasing force comprises a second biasing element (100). Device according to any one of claims 6 to 9, when dependent on any of claims 3 to 5, wherein the first adjusting device comprises first biasing means to provide a first supporting force and the second adjusting device comprises second biasing means to provide a second supporting force. which during use together and simultaneously support the user's foot in any or any combination of a neutral position, an abducted position, an adducted position, a dorsal flexed set and / or a plantar flexed position. Device according to any one of the preceding claims, wherein each or each adjustment device comprises an indicator (120) indicating a relative degree of the adjustment movement. Device according to any one of the preceding claims, wherein the device can be moved to an attached, supported position in which the user's foot is held in any or a suitable combination of a neutral position, an abducted position, an induced position, a dorsal flexed position and / or a plantar-flexed position, without the need for a connecting rod extending between the user's feet or the leg engaging member extending over the user's knees, or the user's legs being held in a bent position. Device according to any one of the preceding claims, wherein the device comprises the leg engaging element comprising a support member (72, 572) into which a leg part of the lower extremity can be accommodated. Device according to any one of the preceding claims, wherein the device comprises the foot-engaging device comprising a shoe or foot plate (86, 586) into which a foot portion of the lower extremity can be accommodated. A rail (556) for supporting immobilization of a body part comprising an orthopedic foot joint device according to any one of claims 1 to 13.