WO2023146508A1

WO2023146508A1 - Ankle-foot orthotics

Info

Publication number: WO2023146508A1
Application number: PCT/US2022/013614
Authority: WO
Inventors: Davinia FONT CALAFELL; Bernat POLL CRESPO; Cristina DOMINGUEZ MANCHADO; Lluis HIERRO DOMENECH
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2023-08-03

Abstract

An ankle-foot orthotic, and parts therefor, the ankle-foot orthotic comprising a foot part to support at least a portion of a sole of a foot of a user, and a leg part to attach to a lower leg of a user, the foot part being releasably attached to the leg part so that the orientation of the foot part relative to the leg part is controlled.

Description

Ankle-Foot Orthotics

BACKGROUND

[0001] An ankle-foot orthotic is a support for a foot, ankle and I or lower leg of a user. An ankle-foot orthotic may be used to control the position and I or motion of the ankle, to compensate for weakness in the foot, ankle and I or lower leg, and I or to compensate for, or correct, deformities. An ankle-foot orthotic may be used to control foot drop, which may be caused by a variety of neurologic and musculoskeletal disorders.

DRAWINGS

[0002] Examples of the present disclosure will now be described with reference to the accompanying Figures, in which:

[0003] Figure 1 show examples of parts of an ankle-foot orthotic to be fitted to a lower leg;

[0004] Figures 2a and 2b show steps in a process of fitting an ankle-foot orthotic created from the parts of Figure 1 ;

[0005] Figure 3 shows an example of a detailed view of a connection between parts of the ankle foot orthotic of Figure 2;

[0006] Figure 4 shows an example of a view of a different ankle-foot orthotic;

[0007] Figures 5a and 5b show examples of parts of a further ankle-foot orthotic;

[0008] Figure 6 shows an example of an ankle-foot orthotic created from the parts of Figures 5a and 5b; and

[0009] Figure 7 shows an example of a detailed view of a connection between parts of the ankle foot orthotic of Figure 6.

DETAILED DESCRIPTION

[0010] When fitted, an ankle-foot orthotic may support the foot, ankle and I or lower leg of a user and may control the position, orientation, and I or motion of the ankle. Use of an ankle-foot orthotic may be advised, or prescribed, for a user following an assessment by a doctor, or other medical advisor, in order to treat or manage conditions such as those mentioned above. An ankle-foot orthotic may be custom fitted to a user to ensure that appropriate tailored support and I or motion control is provided.

[0011] Regular use of an ankle-foot orthotic, or use of an ankle-foot orthotic in compliance with an advised or prescribed regimen, may be beneficial for the treatment of a condition, or may assist in the effective management of a condition, for example by speeding healing, reducing adverse effects, or slowing degradation.

[0012] An ankle-foot orthotic that can be releasably separated into two parts, for example into a foot part and a leg part as described in more detail below, may be more convenient for a user to fit and use than an integral ankle-foot orthotic. Providing a more convenient ankle-foot orthotic may result in the user being more likely to use the ankle-foot orthotic in compliance with the advised or prescribed regimen, or being more likely to use the ankle-foot orthotic more frequently.

[0013] In use the two parts of the ankle-foot orthotic can be releasably coupled together. When releasably coupled together, the coupling between the two parts may limit, or control, relative movement between the two parts across the releasable coupling. By providing a releasable coupling in which relative movement between the two parts across the releasable coupling is limited or controlled, the orientation of one part of the ankle-foot orthotic relative to the other part can be controlled. Reliable and I or predictable control of the orientation of the parts of the ankle-foot orthotic relative to one another when in use may be advantageous for the function of the ankle-foot orthotic, for example it may enable the ankle-foot orthotic to restrict ankle movement to a pre-determined amount, for example as specified by the medical advisor.

[0014] Figure 1 shows a part 1 of an ankle-foot orthotic. The part 1 is a foot part to support at least a portion of a sole 12 of a foot 14 of a user. The part 1 comprises a coupling portion 4 to releasably couple the part 1 to a coupling portion of another part of an ankle-foot orthotic to create an ankle-foot orthotic in which orientation of the part 1 relative to the other part is controlled. Examples of the operation of suitable releasable couplings which can be formed between the coupling portion 4 of part 1 and a coupling portion of the other part will be discussed with reference to Figure 2b. Figure 1 also shows a different part 2 of an ankle-foot orthotic. The part 2 is a leg part to attach to a lower leg 16 of a user. The part 2 comprises a coupling portion 6 to releasably couple the part 2 to a coupling portion of another part to create an anklefoot orthotic in which orientation of the part 2 relative to the other part is controlled. Examples of the operation of suitable releasable couplings which can be formed between the coupling portion 6 of part 2 and a coupling portion of the other part will be discussed with reference to Figure 2b.

[0015] In some examples the foot part 1 may be referred to as a first part and the leg part 2 as a second part. In such an example the foot part 1 may comprise a first coupling portion 4 to releasably couple the first part 1 to a second coupling portion 6 of the second part 2 to create an ankle-foot orthotic in which orientation of the first part 1 relative to the second part 2 is controlled. An ankle-foot orthotic may comprise one foot part and two leg parts, an example of which is described with reference to Figures 5a, 5b, 6 and 7.

[0016]The foot part 1 may comprise a foot part body 18 which may be made from any suitable material, for example a plastic, resin composite, laminate, metal, or a combination of such materials. The foot part body 18 may be manufactured using any suitable technology, for example using moulding techniques such as injection moulding or vacuum forming, or by additive manufacturing, also known as 3D printing. For manufacturing methods which make use a mould, the mould may be made by an additive manufacturing process.

[0017]The foot part 1 is to support at least a portion of a sole 12 of a foot 14 of a user. The foot part 1 may comprise a sole portion 20 and a riser portion 22 extending from the sole portion 20. The sole portion 20 may extend along a first axis 24 to extend under a foot 14 of a user. The riser portion 22 may extend transverse to the first axis 24 towards, or to extend around or above, an ankle 26 of a user. The riser portion 22 may comprise the coupling portion 4.

[0018]The foot part 1 may include a strap 8 to facilitate securing the foot part 1 to a foot 14 of a user. The strap 8 may be permanently secured to the foot part 1 , for example to the foot part body 18, at one end and secured at an opposite end to the foot part 1 by a releasable fixing 10 or in another way . The strap 8 may be permanently secured to the foot part 1 at both ends and be adjustable and / or elastically deformable secure the foot part 1 to a foot 14 of a user. The strap 8 may be removable from the foot part 1 to allow the strap 8 to be replaced, for example with a strap 8 of a different colour, material or length, or if the previous strap 8 was damaged. The strap 8 may be secured to the foot part 1 at each end by a releasable fixing 10 or other way so that the strap 8 could be removed from the foot part 1 . There may be a plurality of straps 8 and there may be a plurality of fixings 10, or a plurality of locations on the strap 8 and I or foot part 1 , to which the releasable fixing 10 can be releasably secured. The plurality of straps 8 may all be the same, or may differ from one another.

[0019]The foot part 1 may include a liner 28 on an inner surface 30. The liner 28 may comprise a sweat wicking material, for example a fabric, to move sweat away from a foot 14 of a user. The liner 28 may include a plurality of layers, for example an outer layer which is visible to a user, and an inner layer. The liner 28 may comprise an inner layer which may include padding arranged between parts of the foot 14 of a user and the foot part body 18 for comfort and I or support. The liner 28 may be permanently affixed to the foot part 1 , for example using an adhesive, or may be removably affixed to the foot part 1 so that the liner 28 can be changed, for example to provide a different technical function or appearance.

[0020]The sole portion 20 of the foot part 1 may comprise a heel cup 38 into which a heel 40 of a user is to fit. Correct fitting of a user’s heel 40 into the heel portion may result in the correct alignment of the rest of the foot part 1 with the user’s foot 14. The sole portion 20 of the foot part 1 may comprise an arch portion 42 to support an arch 44 of a foot 14. The sole portion 20 of the foot part 1 may comprise a ball portion 46 to support a ball 48 of a foot 14. The sole portion 20 of the foot part 1 may comprise a toe portion 50 to support a toe 52 of a foot 14.

[0021] In some examples, the sole portion 20 may extend from the heel cup 38 to the arch portion 42. In other examples, the sole portion 20 may extend from the heel cup 38 to the ball portion 46 and may include an arch portion 42 between the ball portion 46 and the heel cup 38. In yet additional examples, the sole portion 20 may extend from the heel cup 38 to the toe portion 50 and may include an arch portion 42 and a ball portion 46 between the toe portion 50 and the heel cup 38. The ball portion 46 may be located between the toe portion 50 and the arch portion 42.

[0022]The foot part 1 may include lateral portions 54,56 which extend from the sole portion 20 to enclose sides of a foot 14 of a user. In this example the lateral portions 54,56 extend from the sole portion 20 by more than 0.5 cm to enclose sides of the foot 14.

[0023]The foot part 14 may be custom manufactured to fit to a foot 14 of a particular user and may provide tailored support to particular portions of that foot 14. The tailored support may be specified by a medical practitioner, for example a doctor or physiotherapist. [0024]The leg part 2 may comprise a leg part body 32 which, like the foot part body 18 may be made from any suitable material, for example a plastic, resin composite, laminate, metal, or a combination of such materials. The leg part body 32 may be manufactured using any suitable technology, for example using moulding techniques such as injection moulding or vacuum forming, or by additive manufacturing, also known as 3D printing. For manufacturing methods which make use a mould, the mould may be made by an additive manufacturing process.

[0025]The leg part 2 is to attach to a lower leg 16 of a user and may include a strap 34 to facilitate securing the leg part 2 to a lower leg 16 of a user. The strap 34 may be permanently secured to the leg part 2 at one end, for example to the leg part body 32, and secured to the leg part 2 at an opposite end by a releasable fixing 36 or in another way. The strap 34 may be permanently secured to the leg part 2 at both ends and may be adjustable and I or elastically deformable to secure the leg part 2 to a lower leg 16 of a user. The strap 34 may be removable from the leg part 2 to allow the strap 34 to be changed, for example for a strap 34 of a different colour, material or length. The strap 34 may be secured to the leg part 2 at each end by a releasable fixing 36 or other way so that the strap 34 can be removed from the leg part 2. There may be a plurality of straps 34 and there may be a plurality of releasable fixings 36, or a plurality of locations on the strap 34 and I or leg part 2, to which the releasable fixing 36 can be releasably secured. The plurality of straps 34 may all be the same, or may differ.

[0026]The leg part 2 may include a liner 38 on an inner surface 40. The liner 38 may comprise a sweat wicking material, for example a fabric, to move sweat away from a lower leg 16 of a user. The liner 38 may include a plurality of layers, for example an outer layer which is visible to a user, and an inner layer. The liner 38 may comprise an inner layer which may include padding arranged between parts of the lower leg 16 of a user and the leg body part 18 for comfort and I or support. The liner 38 may be permanently affixed to the leg part 2, for example using an adhesive, or may be removably affixed to the leg part 2 so that the liner 38 can be changed, for example to provide a different technical function or appearance.

[0027] A releasable fixing 10,36 is a device which a user can use operate to secure a strap 8,34 to the foot part 1 or leg part 2 and which can be operated to release the strap 8,34. Suitable devices to act as releasable fixings include poppers, clips, clasps, clamps, catches, buttons, buckles and similar. [0028] The leg part 2 may be custom manufactured to fit to a lower leg 16 of a particular user and may provide tailored support to particular portions of that lower leg 16. The tailored support may be specified by a medical practitioner, for example a doctor or physiotherapist.

[0029] In some examples a strap 8,34 may be releasably secured to the foot part 1 or leg part 2 at one or both ends using a means other than a fixing 10,36. For example a strap 8,34 may pass through a loop or hole the foot part 1 or leg part 2 and may be looped back on itself and releasably secured using a fixing 10,36, or simply coupled to another part of the strap 8,34, using a knot, bow or other method, like a shoe lace. [0030] Figures 2a and 2b show steps in the process of fitting the foot part 1 and leg part 2 of an ankle-foot orthotic to a lower leg 16 and a foot 14 of a user.

[0031] A user, or a helper, can initially fit the foot part 1 to the foot 14 of the user. The user may be wearing a sock prior to fitting the foot part 1 . The strap 8 may be released or loosened, to facilitate the placing of the foot 14 onto the foot part 1 . In this example the foot 14 is placed onto the sole portion 20 of the foot part 1 and the heel 40 is arranged in the heel cup 38. Arranging the heel 40 in the heel cup 38 may assist with correctly aligning the foot 14 with the foot part 1 . When the foot part is correctly aligned with the foot 14 of a user, the arch portion 42, the ball portion 46 and the toe portion 50 may be appropriately aligned with the arch 44, ball 48 and toe 52 of the foot 14 to provide support and I or control the position thereof.

[0032] Once the foot part 1 is appropriately aligned with the foot 14, the strap 8 can secure the foot part 1 to the foot 14. For example the strap 8 may be fitted, tightened and I or releasably secured to the foot part 1 over the foot 14 to fit the foot part 1 to the foot 14 so that the movement of the foot 14 relative to the foot part 1 is limited. Limiting relative movement between the foot 14 and the foot part 1 may enhance provision of tailored support by the foot part 1 .

[0033] Fitting the foot part 1 to the foot 14 without a leg part 2 attached may facilitate fitting, for example making it quicker and I or easier to correctly fit the foot part 1 to the foot 14. Fitting the foot part 1 to the foot 14 without a leg part 2 attached may provide a greater flexibility to the user in selecting footwear. Without the leg part 2 attached to the foot part 1 the user may have increased flexibility in the ankle and may be able to put on shoes that might otherwise not be possible, or might be difficult, for example without significant loosening of laces which may be inconvenient, or time consuming. Allowing a user greater flexibility in their choice of footwear may make using the ankle- foot orthotic more convenient and so may increase the likelihood that they will use the ankle-foot orthotic more frequently, or as advised.

[0034] With the foot part 1 attached to the foot 14 of a user the coupling portion 4 of the foot part 1 remains available for coupling to a leg part 2. The coupling portion 4 may be arranged to be located adjacent, or above, an ankle 26 of the user when fitted. The location of the coupling portion 4 relative to the ankle may be determined by a height of a riser portion. This may mean that, when the user is wearing a shoe the coupling portion 4 is more easily accessible. Once the foot part 1 is fitted to the foot 14, and any desired footwear has been put on, the leg part 2 can be connected to the foot part 1 . Making the coupling portion 4 accessible may facilitate coupling the leg part 2 to the foot part 1 .

[0035]To connect the leg part 2 to the foot part 1 the coupling portion 6 of the leg part 2 is moved towards the coupling portion 4 of the foot part 1 . When the coupling portion 4 makes contact with the coupling portion 6, the coupling portions 4,6 can be releasably secured together so that the orientation of the foot part 1 relative to the leg part 2 can be controlled. The foot part 1 and leg part 2, when coupled together, form an ankle-foot orthotic 58.

[0036] Creating an ankle-foot orthotic 58 from two separable parts 1 ,2 allows customisation of the ankle-foot orthotic 58 to a particular use. For example for some activities, such as sports, a user may use a combination of a foot part 1 and a leg part 2 that provide enhanced stability and I or support when compared with other combinations. For a different activity, for example walking to the office, the same foot part 1 may be used, but with a less supportive leg portion 2. A less supportive leg portion 2 may be less bulky and so may be more acceptable for use with certain clothing, or for certain activities.

[0037] A user may be provided with a plurality of foot parts 1 and / or a plurality of leg parts 2 from which a variety of ankle-foot orthotics 58 can be created using different combinations which may be suitable for different circumstances. The foot parts and I or leg parts may differ in, for example, shape, colour, liner, function, strap placement, design and I or material. By providing such flexibility a user may make use of an anklefoot orthotic in circumstances where they may not have previously considered it and this may have health benefits. There are also potential cost benefits as, instead of replacing an entire ankle-foot orthotic, one part 1 ,2 can be changed, for example due to damage, or when a user’s foot grows, or when a purpose of the ankle-foot orthotic changes, for example a health condition changes, or deteriorates.

[0038] Once the leg part 2 and foot part 1 are releasably connected together the strap 34 can secure the leg part 2 to the lower leg 16. For example the strap 34 may be fitted, tightened and I or releasably secured to the leg part 2 around a front of the lower leg 16 to attach the leg part 2 to the lower leg 16. With the leg part 2 secured to the lower leg 16 and the foot part 1 secured to the foot 14 the ankle-foot orthotic 58 may be able to control the position and/or orientation of the foot 14 relative to the lower leg 16.

[0039]The coupling portions 4,6 may be releasably coupled together by any suitable releasable coupling, for example a releasable mechanical fastening, such as a catch, interlocking parts, clip or latch, a magnetic coupling, such as a coupling comprising a permanent magnet aligned with another permanent magnet or a ferromagnetic element, such as a steel or iron portion.

[0040]The releasable coupling between the coupling portions 4,6 of parts 1 ,2 of the ankle-foot orthotic allow the orientation of the foot part 1 relative to the leg part 2 to be controlled. The releasable coupling may prevent or restrict relative movement between the coupling portions 4,6 while the ankle-foot orthotic is being worn. The orientation of the foot part 1 relative to the leg part 2 may change due to flexibility of the material from which the foot part 1 and I or leg part 2 are manufactured. Regions of enhanced, or reduced flexibility can be included to provide a predetermined amount of relative movement and thus may provide control over the orientation of the foot part 1 relative to the leg part 2. Mechanical joints may be included in the foot part 1 and I or leg part 2 to provide a predetermined amount of relative movement between portions of the ankle-foot orthotic on opposite sides of the joint and an example is shown in Figure 5b. A mechanical joint may allow relative movement without flexing of regions of material of the foot part 1 or leg part 2 and so may allow a greater level of tailoring of the control of orientation between the foot part 1 and the leg part 2.

[0041] In some examples the releasable coupling between the coupling portions 4,6 automatically couples the parts 1.2 together when contact is made between the coupling portions 4,6 when moving the parts 1 ,2 together. This automatic coupling between the parts 1 ,2 may facilitate fitting of the leg part 2 to the foot part 1. As noted above, facilitating fitting of the ankle-foot orthotic 58 may make it more likely that a user will use the ankle-foot orthotic 58 more frequently, or as instructed. [0042]The coupling portions 4,6 may include an orientation guide to help align the leg part 2 with the foot part 1. An orientation guide may include a projection from a coupling portion 4,6 that engages with a corresponding recess in the other coupling portion 4,6. The projection and recess may have corresponding tapers so that initial insertion of the protection into the recess may have a wide tolerance for incorrect alignment, but as the coupling portions 4,6 move closer together the tolerance is reduced and the coupling portions are guided towards the correct alignment.

[0043]A magnetic orientation guide may be provided in which magnetic forces align the coupling portions 4,6.

[0044] One of the coupling portions 4,6 may include a magnetic element to magnetically attract an element, for example a magnetic or ferromagnetic element of the other coupling portion 4,6. A suitable magnetic element includes a permanent magnet, for example a rare-earth magnet such as a neodymium magnet.

[0045]The releasable coupling between the coupling portions 4,6 may be adapted to avoid unintentional separation or release of the releasable coupling. This may be achieved through a sufficiently strong magnetic connection, a releasable mechanical connection for example one which uses a predetermined manipulation or action to release the connection, or a combination of coupling types.

[0046] After use the ankle-foot orthotic 58 may be released from the lower leg 16 and the foot 14 by releasing, loosening, or removing the straps 8,34 so that the ankle-foot orthotic 58 can be removed from the user. This removal of the ankle-foot orthotic could take place after any shoe has been removed. In other examples removing the user’s foot 14 from the foot part 1 may also remove the foot 14 from a shoe which can then be removed from the foot part 1 more easily.

[0047] Prior to the ankle-foot orthotic 58 being re-fitted, the foot part 1 and leg part 2 can be separated by releasing the releasable coupling between the coupling portions 4,6. This could occur as a part of removing the ankle-foot orthotic 58 so that the anklefoot orthotic 58 is ready for fitting. In other example fitting of the ankle-foot orthotic 58 comprises a part of separating the foot part 1 and leg part 2 prior to fitting the foot part 1 to a foot 14.

[0048]The separation of the foot part 1 and leg part 2 may take place after the anklefoot orthotic 58 has been removed from the user as it may be easier to manipulate the releasable coupling. In other examples separation of the foot part 1 and leg part 2 may take place while the ankle-foot orthotic is still being worn by a user. Separating foot part 1 and leg part 2 while the ankle-foot orthotic is still being worn by a user may involve preparing the ankle-foot orthotic 58, for example by releasing, loosening, or removing the strap 8 and I or the strap 34.

[0049] Figure 3 shows a detailed view of an example of a coupling portion 4 for use in the ankle-foot orthotic 58 of Figure 2. In this example the coupling portion 4 is the coupling portion of the foot part 1 , but could also be the coupling portion 6 of the leg part 2.

[0050]The coupling portion 4 comprises a plurality of permanent magnets 60 which, when aligned correctly, are magnetically attracted to, and magnetically attract, corresponding magnets on the coupling portion 6. The magnets 60 may not all be oriented with the same magnetic pole exposed and this may facilitate alignment of the coupling portions 4,6.

[0051]The coupling portion may include ramped projections 62 and I or ramped recesses 64 that cooperate with opposing recesses of projections on the coupling portion 6 of the leg part 2 such that the projections 62 fit within corresponding recesses in the coupling portion 6 and the recesses 64 receive projections from the coupling portion 6. The engagement of the projections 62 and recesses 64 with the corresponding parts of the coupling portion 6 may facilitate alignment between the coupling portions 4,6 and may also facilitate separation of the coupling portions 4,6 as discussed below.

[0052] The attraction between the magnets may make it difficult to separate the coupling portions 4,6 by simply pulling them apart against the attraction. Sliding the coupling portions 4,6 relative to one another, for example along a separation axis 66 may make separation easier. The separation axis 66 may be transverse, or perpendicular to the first axis 24. The sliding of coupling portions 4,6 relative to one another along a separation axis 66 may move the magnets of the coupling portions 4,6 out of alignment thereby reducing the attraction force and facilitating separation.

[0053]To facilitate sliding, the coupling portion 4 may be substantially planar with the exception of any projections or recesses which may be provided. In some examples the coupling portions 4,6 may be non-planar. To facilitate relative sliding between the coupling portions 4,6 in a non-planar example the coupling portions 4,6 may be substantially flat in a direction parallel with a separation axis 66 with the exception of any projections or recesses provided. Non-planar coupling portion 4,6 may enhance the security of the coupling between the coupling portions 4,6 by hindering sliding in a direction that is not parallel to a separation axis 68.

[0054]The engagement of the projections 62 and recesses 64 with the corresponding parts of the coupling portion 6 may facilitate alignment between the coupling portions 4,6 and may facilitate separation of the releasable coupling. Sliding of the coupling portions 4,6 relative to one another may cause the ramped projections 62 and associated recesses 64 in the coupling portions 4,6 to interact with the ramps sliding over one another to force the coupling portions 4,6 apart. In some examples the projections 62 and recesses 64 may be ramped to form a conical projection or recess which may allow sliding in any direction. In other examples the ramped shape of the projections 62 and recesses 64 may limit the directions in which sliding is intended, for example to a single direction, or along a single axis.

[0055] Figure 4 shows a different ankle foot orthotic 158 created from a foot part 101 and a leg part 102.

[0056] The foot part 101 has reduced lateral portions 154,156 which extend upwards from the sole portion 120 by no more than 0.5 cm to leave sides of the foot exposed. These reduced lateral portions 154,156 may reduce the support provided for the foot 14. The strap 108 of the foot part 101 includes a releasable fixing 110 which is located over the foot 14 rather than on the foot part body 118.

[0057]The leg portion 102 comprises two straps 134 to attach the leg part to a lower leg 16 of a user.

[0058]The releasable coupling between coupling portions 104 and 106 of the foot part 101 and leg part 102 respectively comprises a releasable catch 68. A portion of the catch 68 may be carried by each of the foot part 101 and the leg part 102. The catch 68 may automatically engage to couple the coupling portions 104,106 together when the coupling portions 104,106 are moved together. The catch 68 can be released by a user interacting with the catch 68 to provide a pre-determined manipulation or action. In this example the user can press a button 70 to release the catch 68 and thereby allow separation of the coupling portions 104,106. In other examples releasing of such a catch 68 may involve a different interaction, for example moving a lever, pressing a pair of buttons, or rotating a latch. The inclusion of a catch 68 with a magnetic coupling may enhance the security of the magnetic coupling by hindering unintentional release of the magnetic coupling. The combination of a catch 68 with a magnetic coupling may allow a less robust catch 68 to be used than might be used if a magnetic coupling was not present.

[0059] In this example the catch 68 is provided in addition to a magnetic coupling, but could be provided instead of such a coupling. In some examples there are a plurality of catches 68 which can be used in addition to, or instead of, a magnetic coupling. The plurality of catches 68 may all be of the same type, or may include different types. [0060] Figure 5a shows a further foot part 201. In this example the coupling portion 204 includes two separate coupling regions 72. In this example there is one on each side of a user’s foot, for example adjacent an ankle of a user. In other examples coupling regions may be provided in other locations depending upon where support is to be provided.

[0061] Figure 5b shows leg parts 202 and 202’ for use with the foot part 201 of Figure 5a. Each leg part 202,202’ includes a coupling portion 206,206’ which can be attached to one of the coupling regions 72. Each leg part 202,202’ includes a joint 74, for example a resiliently biased hinge, which may provide enhanced control over the movement of the leg parts 202, 202’ relative to the foot part 201 and so enhanced control over the motion of the lower leg 16 relative to the foot 14.

[0062] Figure 6 shows an ankle-foot orthotic 258 created from the foot part 201 and leg parts 202,202’. The leg parts 202,202’ are secured to each other by a strap 208 and the strap 208 may be used to attach the leg parts 202,202’ to the lower leg 16. In this example, the strap 208 is threaded onto one leg part 202 and is secured to the other leg part 202’ using releasable fixings 210.

[0063] Figure 7 shows a detailed view of the coupling portion 204 of the foot part 201. The coupling portion 204 is substantially planar and each coupling region 72 includes a plurality of permanent magnets 74. The planar shape of the coupling regions 72 may facilitate sliding of a coupling portion 206,206’ across a coupling region 72 and this may facilitate separation of the coupling portions 204,206,206’.

[0064]As discussed previously, in other examples each coupling portion 72 may include a catch part which can releasably couple to a corresponding catch part of a coupling portion 206,206’ of a leg part 202,202’ to provide a catch which can releasably couple a coupling portion 206,206’ to a coupling region 72. A catch may be used in addition to, or instead of, a magnetic coupling.

[0065] As described previously, the foot part 201 may be fitted to a foot 14 prior to the leg parts 202,202’ being coupled to the foot part 201. In some examples one of the leg parts 202,202’ may be coupled to the foot part 201 prior to the foot part 201 being fitted to a foot 14. Once the foot part 201 is fitted to a foot 14 any remaining leg part 202,202’ may be releasably coupled to the foot part by bringing the coupling portion 206,206’ into contact with one of the coupling regions 72 of the coupling portion 204. [0066]As discussed in connection with previous examples, the releasable coupling between the coupling portion 204 of the foot part 201 and the coupling portions 206,206’ of the leg parts 202,202’ is a magnetic coupling between the magnets 74 of the coupling portions 72 and a corresponding permanent magnets or ferromagnetic elements, such as a steel or iron portions.

Claims

1. A first part of an ankle-foot orthotic, the first part comprising a first coupling portion to releasably couple the first part to a second coupling portion of a second part to create an ankle-foot orthotic in which orientation of the first part relative to the second part is controlled, wherein the first part is one of, and the second part is the other of, (i) a foot part to support at least a portion of a sole of a foot of a user, and (ii) a leg part to attach to a lower leg of a user.

2. A first part of an ankle-foot orthotic as claimed in claim 1 , in which the first coupling portion comprises a magnetic element to magnetically attract an element of a second coupling portion of a second part of an ankle-foot orthotic to the first coupling portion.

3. A first part of an ankle-foot orthotic as claimed in claim 1 , in which the first coupling portion comprises a planar contact surface.

4. A first part of an ankle-foot orthotic as claimed in claim 2, in which the first coupling portion comprises first catch part to releasably couple to a second catch part of the second part.

5. A first part of an ankle-foot orthotic as claimed in claim 1 , in which the first part includes a strap to attach the first part to a user.

6. An ankle-foot orthotic comprising a foot part to support at least a portion of a sole of a foot of a user, and a leg part to attach to a lower leg of a user, the foot part being releasably attached to the leg part so that the orientation of the foot part relative to the leg part is controlled.

7. An ankle-foot orthotic as claimed in claim 6, in which the foot part comprises a sole portion and a riser portion, the sole portion extending along a first axis to extend under a foot of a user and a riser portion extending transverse to the first axis towards, or to extend around, an ankle of a user, the riser portion comprises a first coupling portion and the leg part comprising a second coupling portion.

8. An ankle-foot orthotic as claimed in claim 7, in which the first coupling portion comprises a magnetic element which magnetically attracts an element of a second coupling portion of the leg part to releasably attach the foot part to the leg part to prevent relative movement between the first coupling portion and second coupling portion.

9. An ankle-foot orthotic as claimed in claim 8, in which the element of the second coupling portion of the leg part is a magnetic element.

10. An ankle-foot orthotic as claimed in claim 8, in which the first coupling portion comprises first catch part releasably coupled to a second catch part of the second coupling portion.

11. A method of fitting an ankle-foot orthotic to a user, the ankle-foot orthotic comprising a foot part to support at least a portion of a sole of a foot of the user, and a leg part to attach to a lower leg of a user, the foot part being releasably attachable to the leg part so that the orientation of the foot part relative to the leg part is controlled, the method comprising positioning a foot of a user on a foot part, then releasably attaching a leg part to the foot part and attaching the leg part to the lower leg of the user.

12. A method as claimed in claim 11 , in which the method comprises attaching the foot part to the foot of the user.

13. A method as claimed in claim 11 , in which the method comprises separating the foot part from the leg part prior to positioning a foot of the user on the foot part.

14. A method as claimed in claim 13, in which the foot part and the leg part are attached to one another at a joint plane and separating the foot part and the leg part comprises sliding the foot part relative to the leg part parallel to the joint plane.

15. A method as claimed in claim 14, in which releasably attaching a leg part to the foot part comprises moving the leg part towards the foot part in a direction transverse to the joint plane.