GB2571433A

GB2571433A - Patient rehabilitation device

Info

Publication number: GB2571433A
Application number: GB1900071.0A
Authority: GB
Inventors: William Allonby Wileman Oliver; James Hughes Samuel; Benson Lucas; Beth Singleton Anna; Cunnah Dylan; Huddart Jordan
Original assignee: BAE Systems PLC
Current assignee: BAE Systems PLC
Priority date: 2018-01-08
Filing date: 2019-01-03
Publication date: 2019-08-28
Anticipated expiration: 2039-01-03
Also published as: GB201800267D0; WO2019135081A1; GB2571433B

Abstract

A rehabilitation apparatus 30 with a foot support 32 which is pivotally attached, by way of at least one pivot joint 33a to a leg support 34; a moveable plate 32a mounted on the foot support; and a motor to control the degree of pivotal motion of the foot support 32 in relation to the leg support 34 by way of the at least one pivot joint 33a. The foot 37a support may have a base and a side wall comprising an attaching structure which attaches to an apex support structure 33 of the les 37b support. The pivot joint may be self-lubricating. The foot plate may move parallel to the foot support. There may be foot restraint strap 31a or leg restraint strap 31b. The motor may be a stepper motor and have at least one gear. There may be a control panel 36 with an emergency stop. The device may rehabilitate an ankle joint 37 moving it between dorsiflexion and plantar flexion.

Description

PATIENT REHABILITATION DEVICE

FIELD OF INVENTION

The invention relates to a joint support and manipulation device for use in the medical rehabilitation industry. More particularly, the invention relates to rehabilitation apparatus for use in the rehabilitation of ankle joints. The invention is particularly useful for the rehabilitation of ankle joints in medical patients fitted with Taylor Spatial Frame (TSF) or lllizarov frames, or for medical patients who have previously been fitted with a cast.

BACKGROUND

In the field of joint rehabilitation, whether following a direct injury or medical treatment/surgery, patients may be fitted with various medical supports such as casts or frames to prevent undue movement of the injured limb or joint. Isolating the limb or joint can allow a degree of structural repair to occur as well as prevent further injury as a result of sudden or strenuous movement. Devices such as frames or casts may cause the patient to suffer stiff joints as the prevention of movement can cause the associated tendons or ligaments to tighten. Though the joint or limb may repair structurally, patients may, as a result of limb isolation, be left with reduced movement of the joint and in some severe cases, they may be unable to move the limb and/or or joint.

In order to rehabilitate the limb and regain movement of the joint, physiotherapists are employed to manipulate the joint to loosen the tendons and ligaments and increase flexibility and range of movement. This can be very time consuming, often requiring multiple sessions of physiotherapy over many weeks or months.

Rehabilitation often involves the physiotherapist flexing the ankle back and forward. The ankle is most often moved between dorsiflexion (where the toes are brought closer to the shin, thus decreasing the angle between the dorsum of the foot and the leg) and plantar flexion (where the toes are moved

-2away from the shin, thus decreasing the angle between the sole of the foot and the back of the leg). The intensity of these movements is often increased as the patient shows signs of progression.

It is the intent of the inventor to aid in the automation of this type of joint physiotherapy whilst maintaining or improving the medical benefits.

SUMMARY OF INVENTION

According to a first aspect of the invention there is provided an apparatus for joint motion control, between at least a first limb and a second limb, comprising a first limb support and a second limb support, a moveable plate, said moveable plate being mounted on the first limb support, wherein the first limb support is pivotally mounted, about a pivot joint, to a support structure, which is attached to the second limb support, and a resilient bias, used to control the degree of pivotal motion of the first limb support; in relation to the second limb support such that the first limb support coincides with the first limb to be motioned controlled in relation to the second limb.

The arrangement allows the joint between said first and second limbs to be isolated, controlled and moved by securing a first limb in its natural plane in relation to a second limb. In an example arrangement, where the joint to be exercised is an ankle the lower leg may be secured against the second limb support in its natural plane, with the foot being secured against a first limb support in its corresponding natural plane, thereby isolating the two limbs. This allows the ankle joint motion to be controlled by the action of the device.

In alternative arrangements the limb may be a large limb, such as the upper leg with the lower leg being secured and the knee joint isolated or a smaller limb pair such as either side of a knuckle joint on a patient’s hand.

In use the apparatus moves a limb about a pivot point in the natural plane of movement, either partially through the limb range or entirely through the limb range depending on the limitations of the joint and the stage of the patient’s therapy.

-3The range of movement of limb may be controlled to be limited and increased as therapy progresses as well as the speed through which the limb is moved through the range.

The movement of a first limb in relation to a second limb requires the joint to be moved to be positioned relative to the pivot point; the pivot point of the rehabilitation device may be mounted on a support structure located on the second limb support. The support structure may be an apex support structure. Conveniently the first limb support may comprise a further apex support. The apex support structure and further apex support structures may be joined at the pivot point.

The first limb support may be attached to the support structure, about the pivot joint, utilising a pivotal mechanical fixing using a self-lubricating metal. The pivot joint may be passive, such that it moves freely; it may comprise a resilient bias to provide resistance to the user.

In conjunction with the moveable plate the first limb may be moved to adjust the pivot point in relation to the joint to be exercised. This point may change as the size of limbs the invention is to accommodate changes, whether due to the size of the patient or the joint to be exercised.

The moveable plate may be either slideably or mechanically adjustable to move the joint, which connects the first and second limb, into alignment with the pivot point. In a preferred arrangement the moveable plate may be slideably adjusted with respect to the first limb support as this allows the limb to find the joint’s point of rotation naturally to the patients comfort and so prevents unnecessary intervention by a professional to mechanically adjust the plate.

The support structure may further comprise a swing stop to engage with the first limb support to prevent pivoting, such as, for example to prevent the first support structure from either impacting the control panel of the rehabilitation device or over-extending the joint to be exercised. The swing stop may be rigidly fixed or mechanically adjustable in order that it may be moved to accommodate differing ranges of joint motion.

-4In order to provide maximum support for the first limb, a prop may be tailored to fit differing limb types, for example where the first limb is a foot (where the ankle is the joint to be exercised) the moveable plate may further include a raised portion at the end of the moveable plate to provide support for the first limb and to aid in its retention.

Similarly the first limb support may comprise a retention strap. The first limb support may comprise at least one slot for the insertion of the retention strap which may hold the first limb against the first limb support, once the first limb is in place. The retention strap may be permanently attached to the first support and in use, placed over the first limb and reversibly inserted into the slot, however alternatively at least two slots may be included as part of the first support to allow the restraint strap to be completely removed from the rehabilitation device or installed on the rehabilitation device by insertion into both slots.

The first limb support and/or moveable plate may further comprise a support cushion constructed from plastic, foam or gel to add to the patient comfort and the limb support.

In order that the second limb is supported effectively, the second limb support may be constructed with a curved recessed portion to allow the limb to sit in the second limb support.

This adds a degree of both comfort and movement control and may vary depending on the limb to be supported, for example the recessed portion may be significantly greater in depth and breadth with larger limbs than limbs such as finger portions.

The second limb support may also comprise a support cushion constructed from plastic, foam or gel.

The second limb support may further comprise retention straps, such as, for example the second limb support may comprise at least one slot, running through its length for the connection of a limb retention strap to secure the limb to the second limb support and prevent undue movement to the second limb in

-5relation to the first, whilst allowing a full range in joint motion. The restraint strap(s) may be permanently mechanically fastened or reversibly fastened by inclusion of an additional slot on the second limb support for the insertion of an additional end of the restraint strap.

The resilient biased means may be located within the pivot joint, or may be located such that it provides resilience between the first and second limb support.

The motion of the first limb support in relation to the second limb support, in a simplified arrangement may be patient controlled through the use of a resilient biased means, for example non-mechanical resistance devices, such elastic straps, springs, rubber mounts, thereby utilising the patient’s own efforts to move against the resistance of the elastic, thereby strengthening the joint. The non-mechanical resistance devices may be affixed to the first and second limb supports, and the resistance changed by changing the resilience of the elastic or spring.

In a preferred arrangement the motion of the first limb support in relation to the second limb support may be a mechanically controlled means, for example a motor such as a stepped motor, which is programmable to allow for a specific selection of range of movement and force to be applied, thereby creating a number of different training programmes. In use the motor may cause either the first limb support and/or second limb support to move through a range of different programmed angles of pivot, about said pivot joint, in order to move the first limb, in relation to the second limb, and thereby cause the joint between the first limb and second limb to work through a controlled motion and range.

The motor may be located within the pivot joint or located in a housing and drive the first limb support or second limb support, about said pivot joint.

As the motor is intended to control the motion of the first limb and second limb it is a requirement of the motor that it is capable of delivering a range of force in order for it to move the first limb support or second limb support as required.

-6In an embodiment where the motor is a stepped motor, the stepped motor may deliver from Okg or 0 N to 500kg or 490.5N, of force over the range of movement traversed by the first or second limb supports, more preferably from 50kg to 240kg or 235.4N of force over the range of movement traversed by the first limb support.

The rehabilitation device may include a control panel to input programs to control the operation of the resilient means. The control panel may be fixed to the device or be detachable to allow remote operation. The control panel may be used to enable the selection of an exercise program, after which it will cause the motor to move the first limb support, second limb support or both, through a range of motions, varying the angle between the first limb support and second limb support, the speed or both speed and the angle. The control panel may include a display to allow the operator to select training programs, a means to manually adjust the resistance to movement of the first limb support or second limb support or various status indicators to inform the operator of the device as to how it is functioning. In a preferred arrangement the control panel comprises an emergency stop to immediately halt the movement motor and therefore the motion of the first limb support, second limb support or both.

According to a second aspect of the present invention, there is provided a method of joint motion control with a device as discussed herein, wherein: a second limb (e.g. a leg) is placed on the limb support with a first limb (e.g. a foot) placed on the moveable plate of the first limb support and the first limb and first limb support is pivoted in relation to the second limb support in order that the angle between the second limb and first limb is increased and decreased under control of the resilient bias.

According to a third aspect of the present invention, there is provided a rehabilitation apparatus (also referred herein as an ankle rehabilitation apparatus, device or system) comprising: a foot support and a leg support; wherein the foot support is pivotally attached, by way of at least one pivot joint, to the leg support; and wherein the rehabilitation apparatus further comprises: a

-7 moveable foot plate mounted on the foot support; and a motor adapted/configured to control the degree of pivotal motion of the foot support in relation to the leg support about the at least one pivot joint.

According to a fourth aspect of the present invention, there is provided a rehabilitation apparatus comprising: a foot support and a leg support; wherein the foot support is pivotally attached, by way of at least one pivot joint, to the leg support; and wherein the rehabilitation apparatus further comprises: a moveable foot plate mounted on the foot support; and means for controlling the degree of pivotal motion of the foot support in relation to the leg support about the at least one pivot joint.

The foot support may comprise a base, which is preferably flat, and the foot support may further comprise at least one side wall (preferably two opposing side walls) extending (at approximately 90 degrees) from the base, e.g. extending upwards from the base. The at least one side wall may comprise at least one attaching structure. The at least one attaching structure (e.g. an apex structure) may extend from, for example up from and parallel to, the at least one side wall. Preferably there are two side walls, which are opposing, with respective side wall attaching structures (a first attaching structure and a second attaching structure). These attaching structure(s) are structures that function to attach the foot support to the leg support. Preferably the second attaching structure is the attaching structure nearest the motor. The foot support may further comprise a back wall, preferably extending between the two side walls. This back wall may function to stop the moveable plate from sliding off the foot support.

The leg support may have two side walls, a front wall and a back wall. Preferably the front wall (i.e. the wall nearest to the patient’s knee in use) is shaped ergonomically (e.g. concavely curved to fit the shape of a patient’s calf/lower leg) so as to provide comfort to the patient. Preferably the back wall (i.e. the wall opposite the front wall) of the leg support extends into a control panel.

-8The leg support may comprise at least one support structure and the foot support may be pivotally attached, by way of the at least one pivot joint, to the at least one support structure of the leg support. In other words, the support structure may be joined to the attaching structure at a pivot joint.

The at least one support structure of the leg support acts to support/hold the foot support (and associated moveable foot plate). Preferably the at least one support structure is rigid and does not move during operation of the rehabilitation device. Preferably the leg support has two support structures and the foot support is pivotally attached to the leg support by way of two pivot joints.

As such, in a preferred example, there are two support structures - a first support structure and a second support structure and there are two foot support attaching structures - a first attaching structure and a second attaching structure. In this preferred example, the first attaching structure is pivotally attached, by way of a pivot joint to the first supporting structure and the second attaching structure is pivotally attached, by way of a (different) pivot joint to the second supporting structure.

In a preferred embodiment, therefore, the rehabilitation apparatus comprises a foot support comprising first and second attaching structures; a leg support comprising first and second supporting structures; wherein the first attaching structure is pivotally attached, by way of a first pivot joint, to the first support structure; and the second attaching structure is pivotally attached, by way of a second pivot joint, to the second support structure; and wherein the rehabilitation apparatus further comprises a moveable foot plate mounted on the foot support; and a motor adapted to control the degree of pivotal motion of the foot support in relation to the leg support by way of the first and second pivot joints.

The motor may be adapted or configured to control the degree of pivotal motion of the foot support by any suitable means known in the art. The motor may, for example, drive mechanical means of rotating the foot support about the

-9pivot point(s). A suitable example includes the use of a motor to control gears which rotate the foot support. For example, the motor may turn a first gear that engages with a second gear, which second gear rotates the foot support. The first gear rotates by the action of the motor by way of a drive shaft. The cogs of the first gear engage with the cogs of the second gear, thus turning the second gear. The second gear may rotate the foot support about the pivot joints(s) by either being attached (e.g. bonded) to the foot support or by being integral to the foot support (e.g. made from the same additive manufactured piece).

The pivot joint(s) may be any suitable pivot joint known in the art, for example a bush and pin receptacle, made from any suitable material known in the art. Preferably the pin is aluminium thus providing a lightweight and strong pivot joint.

The pivot joint(s) may be a self-lubricating pivot joint. Preferably the at least one pivot joint comprises a self-lubricating metal. Advantageously selflubrication provides a smooth pivoting motion and also reduces wear. Any suitable, medical grade self-lubrication method known in the art may be used, for example Oilite® (porous bronze).

In a preferred example the motor is adapted or configured to control the degree of pivotal motion of the foot support by way of a pinion (first gear) and half-moon gear (second gear) mechanism. Preferably, the half-moon gear extends down from the attaching structure of the foot support (i.e. extends away from the pivot joint and past the base of the foot support). In other words, the half-moon gear (the second gear) is integral to the attaching structure of the foot support. In other words, the base, side walls of the foot support, the attaching structure and the half-moon gear may be made in the same additive layer manufacturing process. In use, the motor powers the rotary movement of the pinion, causing the cogs of the pinion to engage with the cogs of the half-moon gear. This in turn causes the attaching structure of the foot support to pivot about the pivot point (e.g. the second pivot joint), thus pivoting the foot support about the pivot points (e.g. the first and second pivot points).

-10Preferably at least one of the support structures (for example the second support structure; that is the support structure nearest the motor) also comprises a guard piece. The guard piece functions to stop entrapment of, for example, fingers in the gear mechanism, e.g. the half-moon gear and pinion arrangement. The guard piece can be of any suitable shape that functions to encapsulate the half-moon gear of the attaching structure. A guard piece may also be included on the first support structure (the support structure opposite the motor) so as to cover the gap created by the rotation of the foot support. The guard piece(s) may be permanently fixed or removable.

The support structure(s) may be attached to the leg support by any suitable method or attachment device known in the art, for example by way of one or more dove joints. Preferably the support structure(s) is rigidly attached to the sides/side walls of the leg support. The attachment device may be reinforced. For example, the dove joint(s) may have a threaded insert, such a grub screw, which acts to brace the support structure against the walls of the leg support. Advantageously this reduces gear wear by reducing deleterious movement.

The support structure may be of any shape or design. Preferably the support structures are triangular in shape - that is they are apex structures. This advantageously provides optimum structural strength whilst minimising the weight and thus costs of manufacture. This is particularly advantageous in helping to provide a lightweight, cheap rehabilitation device that can be easily used by bed-ridden patients.

The support structure (e.g. the support structure nearest to the motor) may further comprise a safety device called a swing stop. The swing stop may be considered an extension to the guard piece. The swing stop functions to engage with the foot support and prevent further pivoting of the foot support past the programmed extreme limit of dorsiflexion and extreme limit of plantar flexion. In other words, the swing stop acts to prevent the foot support from pivoting to a point where the control panel is impacted. In addition or

-11 alternatively, infilling of certain cogs in the half moon gear at certain determined points in the half moon gear can be utilised as a safety mechanism. This infilling acts as a physical way of stopping over travel of the gear and thus over extension of the foot. The rehabilitation apparatus of the present invention also may comprise at least one “soft stop”, for example one or more limit switches. These are preferably located proximate to or touching the half-moon gear. When the “soft stop” is inadvertently hit, the motor is programmed to stop and most preferably reverse back, thus moving the foot support away from the impinging article (e.g. a finger).

One of the advantages of the present invention is the use of a moveable (e.g. slideable) foot plate mounted on the foot support. The moveable foot plate is preferably adapted or configured to move (e.g. slide) parallel to the base of the foot support. One example of such a configuration is that the moveable foot plate is mounted on the foot support by way of at least one slot recessed into the at least one side wall.

Preferably there are two foot support side walls with respective slots, which act to mount the moveable foot plate within the foot support. In other words, the moveable plate could be considered to sit within the volume defined by the back wall of the foot support and the two side walls of the foot support. The slots in the side walls hold the moveable foot plate above the base of the foot support and allow the moveable foot plate to move/slide parallel to the base of the foot support, towards and away from the back wall. In essence, the moveable foot plate “hovers” or “floats” above the base of the foot support - it does not contact the base of the foot support. The slots/grooves may be tapered and preferably are U-shaped channels. This type of tapering advantageously aids in the sliding motion of the moveable foot plate. The moveable foot plate is preferably a solid plate with side edges that are tapered so that they fit within the tapered slot of the side walls of the foot support.

In use, and when the device is set in motion, the patient’s foot (i.e. the sole of the foot) sits on the moveable foot plate (held in place by way of retention straps) and the patient’s heal rests against the back wall of the moveable foot plate. In other words, the back wall of the moveable foot plate could be considered a heal support, a limb cradle or an ankle rest. Accordingly the back wall may be ergonomically designed to support an ankle e.g. it may be curved.

The end of the foot support opposite to the foot support back wall is open so as to allow movement of the moveable plate away from the foot support back wall (and out of the volume defined by the foot support back wall and the two side walls of the foot support).

In this manner, while the foot support is pivoting by way of the pivot joint(s), the patients’ foot (held to the slideable foot plate) is able to move towards and away from the back wall of the foot support, parallel to the base of the foot support. This advantageously allows a constant adjustment and readjustment of the ankle’s natural centre of rotation. It further advantageously finds the ankle’s pivot point/ankle’s centre of rotation naturally without the need for it to be set manually. This not only reduces the set up time ofthe device but also provides a significant advantage over known ankle rehabilitation devices that rely on manually setting the ankle’s pivot point. Such prior art devices often suffer from the physiotherapist incorrectly setting the ankle’s natural pivot point. The rehabilitation apparatus of the present invention does not suffer from this problem and thus the likelihood of damage to the ankle is thus significantly reduced with its use. Further, the rehabilitation device ofthe present invention is able to accommodate different foot sizes through means of the “floating” pivot point and moveable plate.

The leg support preferably has an upper surface that is either flat or comprises a curved recessed portion (i.e. concave - the leg support could be considered to have a trough). The upper surface of the leg support is the surface that supports the leg (more specifically the calf of the leg) or leg with frame, when in use.

-13When the upper surface of the leg support is concave/has a trough, advantageously patients with a TSF or I Ilizarov frame are able to use the device - i.e. the trough in the leg support accommodates the TSF or lllizarov frame. As such, the rehabilitation device is particularly useful for the rehabilitation of patients who have suffered complex fractures. In this instance, it is preferable that no cushioning is used on top of the upper surface of the leg support.

When the upper surface of the leg support is flat, patients without a frame attached to their leg may use the device. Advantageously this means that the device can also be used on patients that have suffered non-complex fractures (for example ones that previously required a cast). In this instance, it is preferable that cushioning is provided on top of the flat, upper surface of the leg support.

The moveable foot plate and/or the leg support may comprise at least one retention strap. The retention strap may be a toe strap, a heel strap or a leg strap.

Preferably the moveable foot plate has one toe strap and one ankle strap. The ankle strap acts to stop or reduce natural ankle lift thus enabling most efficient manipulation of the ankle. Preferably the retention strap(s) are slideable. Advantageously this allows different foot sizes to be accommodated. The slideable retention strap(s) (e.g. the toe and/or heel strap(s)) may slide within a slit (preferably two slits) in the moveable foot plate. Advantageously this means that the retention straps do not impede the movement of the moveable plate.

Preferably the leg support has two leg retention straps. The strap(s) ensure that the leg or leg with fixture device/frame does not move freely when the device is running - the leg retention straps act to clamp the leg, or leg with frame, in place. The retention strap(s) are attached to the leg support by way of slots in the side walls of the leg support. This allows the retention straps to reach over the patient’s leg, or leg with cage, and hold the leg (leg and cage) to the leg support.

-14Advantageously, the combination of a trough with retention strap(s) allows varying heights, widths, and orientations of cages to be used in conjunction with the device.

Preferably the retention straps are flexible, that is they allow a degree of movement so that patient doesn’t feel discomfort. The retention straps may be cushioned. Preferably the retention straps are covered with an outer coating, for example a plastic coating. The plastic coating is preferably Dartex® or any other medically approved coating material. This type of coating is easily cleaned, and helps in infection control within hospitals.

The moveable plate and/or leg support may also further comprise a support cushion constructed from plastic, foam or gel. The support cushion may be made from a foam e.g. a silicone foam, for example HT800 flame retardant foam Silex. The support cushion(s) may be attached to the moveable foot plate and/or leg support by way of Velcro or any other suitable medically approved temporary fixing material. The support cushion is preferably covered by Dartex® polyurethane or any medically approved covering material. A support cushion is particularly preferred when the upper surface of the leg support is flat and the device is being used on patients with simple fractures (without a frame). Such a covered support cushion may also be used over the retention straps.

A further advantage of the present invention is the use of a motor configured to control the degree of pivotal motion of the foot support. The motor may be configured as such by further comprising at least one gear. Further, preferably the motor is a programmable stepper motor.

The stepper motor is able to be programmed to automate the exercising of the patient’s ankle. The stepper motor powers the gears (in for example the half-moon gear and pinion) which rotate the foot support about the pivot joints thus placing the foot in dorsiflexion and plantar flexion. The motor can be programmed to vary the level of intensity and by limiting or expanding the range of movement or speed at which the foot support rotates. The stepper motor may be programmed with Arduino code allowing, for example, identification of the

-15extreme parameters (e.g. extreme limit of dorsiflexion and extreme limit of plantar flexion), the limit of the patient’s range of movement, rehabilitation programs which move within a percentage of the patient’s range of movement, programs at various speeds as well as warm-up routines and full speed and range of movement programs.

By automating in such a manner, a physiotherapist is not required to manually manipulate the ankle joint and is free to undertake other tasks. Further, the stepped intensity allows the rehabilitation device to accommodate patients with varying levels of required rehabilitation. Different programs can be created to suit different patients and requirements. The use of programmed extreme limits of dorsiflexion and plantar flexion also advantageously provide safety to the patient - they can undertake their own physiotherapy in the knowledge that their ankle will not be overextended past that considered necessary or safe by the physiotherapist.

The motor preferably has a rotary encoder which measures the angular position of the foot plate. Preferably the rotary encoder is attached to the back of the motor, however any other suitable locations are also envisaged. The use of a rotary encoder advantageously allows accurate control and measurement of the rotation of the foot support. Preferably the motor and rotary encoder are proximate to the half-moon gear so as to provide the most accurate positioning data.

The motor may be powered by any suitable source, for example by a mains source or battery source. A transformer may be used in addition to these sources to supply the device with voltages up to 90V, for example mains to 12V, mains to 24V, mains to 48V or mains to 62V.

The rehabilitation apparatus may include a control panel which functions to control the operation of the motor and thus the movement of the foot support. The control panel may be fixed to the device or may be detachable to allow remote operation. The control panel is preferably located proximate to the back wall of the leg support (i.e. nearest the patient’s foot in use). The control panel

-16may be any suitable type of method of controlling the rehabilitation device. For example, the control panel may have a means of starting the motor and thus the motion of the pinion and half-moon gear (e.g. a start button). Preferably the means for starting the motor (e.g. the start button) is a delayed means - in other words it requires the user to deploy/hold the button for a minimum of, for example, 2 seconds. This ensures that the motor is not accidentally started by inadvertent contact with the button. The control panel may also have a means of immediately halting the movement of the motor and thus the foot support (e.g. an emergency stop button). The control panel may also include a display to allow the operator to select training programs, a means to manually adjust the resistance to movement of the foot support or various status indicators to inform the operator of the device as to how it is functioning. The control panel may be used to enable the selection of an exercise program, which controls the ankle’s rehabilitation by, for example, varying the angle between the foot support and the leg support, the speed of rotation of the foot support about the pivot point(s) or both. The control panel may also have a plurality of mode buttons, with pre-programmed modes of operation (for example a warm up mode, an intermediate mode and a full running mode), a means for varying the speed and/or time of physiotherapy (e.g. a speed and time setting button) and a means of resetting any programs currently in progress (e.g. a reset button).

The rehabilitation apparatus may also further comprise a means for the patient to halt the physiotherapy e.g. a hand held emergency stop for the patient, for when, for example, the physiotherapy gets too painful.

The foot support (base, back wall and side walls), leg support (base, back wall, front wall and side walls), moveable plate, support structure, attaching structure (and associated half-moon gear) and/or control panel (“these parts”) are made from any suitable method or material known in the art. For example, these parts can be any suitable metal or plastic. Preferably these parts are solid but could, however, be hollow or honeycombed to reduce the weight of the rehabilitation device. The metal parts may be cast. The plastic parts may be injection moulded.

In a preferred example, these parts are manufactured by additive layer manufacturing, for example by fused deposition modelling. Preferably they are made from any suitable printable plastic, for example Acrylonitrile Styrene Acrylate (ASA). This provides parts with good wear and UV resistance. Most preferably these parts are manufactured by additive layer manufacturing and then are post-processed to reduce or eliminate microcavities/pores. This can be achieved by any suitable method known in the art, for example sintering. Advantageously this helps with infection control within hospitals. The cogs of the half-moon gear may alternatively be formed from a metal such as titanium (by way of additive layer manufacturing, for example). This would advantageously provide good wear resistance for the cogs. These metal printed cogs may then be fused to the plastic attaching structure.

Whilst the invention has been described above, it extends to any inventive combination of the features set out above, or in the following description, drawings or claims.

Exemplary embodiments of the device in accordance with the invention will now be described with reference to the accompanying drawings.

BRIEF DESCRIPTION OF FIGURES

Figure 1 shows an example rehabilitation device as viewed from the top of the device.

Figure 2 shows an example rehabilitation device as viewed from the bottom of the device.

Figure 3 shows an example rehabilitation device when in use with a leg and foot.

Figure 4 shows an example rehabilitation device as viewed from the side of the device.

-18Figure 5 shows an example rehabilitation device as viewed from the back of the device.

Figure 6 shows an example rehabilitation device illustrating the halfmoon pinion gear system.

Figure 7 shows an example rehabilitation device with an lllizarov or TSF frame.

DETAILED DESCRIPTION

Referring to Figure 1, there is shown a rehabilitation device/apparatus 10 comprising a foot support 12 and a leg support 14, and wherein the foot support 12 has a slideably adjustable moveable plate 12a. The slideably adjustable moveable plate 12a has a limb cradle 15 (a heel support) at a first end, which may act as an ankle/heel rest. The foot support 12 also has an attaching apex structure 12b, which is attached to a support apex structure 13 at the pivot joint 13a. The foot support 12 is able to move pivotally around the pivot joint 13a in order to provide controlled movement to the ankle connecting the foot and leg (not shown). A control panel 16 is also provided to allow movement routines to be selected or entered into the rehabilitation device 10 therein allowing for various treatment routines to be selected as required by individual patients. In the example shown the leg support 14 has a concave shape/surface (a trough) to provide a degree of additional comfort to the leg, allowing the leg support 14 to support the leg on contact. In the example given the leg support 14 further comprises a leg support recess 18, allowing a leg restraint strap (not shown) to be fitted if desired. The leg restraint strap may be a permanent attachment or may be reversibly fixed, as is the case in Fig 1, wherein the leg support recess 18 extends to the top of the leg support 14 to allow a leg restraint strap to be slideably inserted into the leg support recess 18. While in use the leg restraint strap may be tightened to draw the leg close to the leg support 14 thereby reducing or preventing leg movement and in turn reducing or preventing unintended movement of the ankle.

-19Referring to Figure 2, there is shown a rehabilitation device/apparatus 20 comprising a foot support 22, shown from below, and pivotally attached, via pivot joint 23a, to an apex support structure 23. In the example shown, the apex support structure 23 further comprises a swing stop 22b, which acts to prevent the foot support 22 from pivoting to a point where the control panel 26 is impacted. Further the swing stop 22b, acts to prevent the ankle (not shown) from being overstretched.

The swing stop position on the apex support structure 23 may be fixed as shown in Fig 2 or adjustable to fit a different range of joint motion. As with Fig 1 the leg support 24 is shaped to include a concave portion (e.g. a trough) and is fitted with a leg support recess 28 for the inclusion of a leg restraint strap (not shown).

Referring to Figure 3, there is shown a rehabilitation device/apparatus 30 in use, comprising a foot support 32 which is attached to a support apex structure 33 of a leg support 34. A first limb 37a, in this example a foot, is sat on the slideably adjustable plate 32a, allowing the foot to naturally slide to suit its pivot point, the foot 37a being secured in place by a foot restraint strap 31a. The second limb 37b, in this case a leg (the range of diameters of the leg being denoted by the black ring 40), rests on the leg support 34 and is secured in place with a leg restraint strap 31b. In use the foot 37a and leg 37b are placed on the rehabilitation device 30 and utilising the adjustable plate 32a the foot 37a is moved to locate the ankle joint’s 37 natural pivot point in relation to the pivot joint 33a. The rehabilitation device 30 exercise program may then be entered via the control panel 36, following which the foot support 32 moves pivotally, in a controlled fashion, to exercise the ankle joint 37.

Referring to Figure 4, there is shown a rehabilitation device/apparatus 40 which has a foot support 42, with slideably adjustable moveable foot plate 42a, and a leg support 44.

The foot support 42 has a flat base 42d (with upper and lower surfaces) and, extending upwards at 90 degrees to the base 42d (the upper surface of the

-20base), two side walls - a first side wall 42c(1) and a second side wall 42c(2). A first attaching structure 42b(1) extends up from, and parallel to, the first side wall 42c(1) and a second attaching structure 42b(2) extends up from, and parallel to, the second side wall 42c(2).

The leg support 44 has a first supporting apex structure 43(1) and a second supporting apex structure 43(2). The first attaching apex structure 42b(1) is attached to the first supporting apex structure 43(1) at a first pivot joint 43a(1) (a first bush and pin receptacle). The second attaching apex structure 42b(2) is attached to the second supporting apex structure 43(2) at the second pivot joint 43a(2) (a second bush and pin receptacle). This allows the foot support 42 to move pivotally around the pivot joints 43a(1) and 43a(2) in order to provide controlled movement to the ankle (not shown).

The slideably adjustable moveable plate 42a has a heel support 45, which may act as an ankle/heel rest.

In the example shown the leg support 44 has a trough 44a (e.g. a concave upper surface of the leg support) to support the leg (not shown) in use.

A control panel 46 is also provided to control the movement of the rehabilitation device.

Referring to Figure 5, there is shown a rehabilitation device/apparatus 50 which has a foot support 52, with slideably adjustable moveable foot plate 52a, and a leg support 54 (with a cushioned flat upper surface 54b).

The foot support 52 has a flat base 52d (with lower surface shown) and extending upwards at 90 degrees to the base 52d, two opposing side walls - a first side wall 52c(1) and a second side wall 52c(2). The moveable foot plate 52a is mounted on the foot support 52 by way of a first u-shaped slot 52e(1) in the first side wall 52c(1) and a second u-shaped slot 52e(2) in the second side wall 52c(2). These slots in the side walls of the foot support hold the moveable foot plate 52a above the base 52d of the foot support 52 (more specifically, above the upper surface (not visible) of the base 52d) and allow the moveable foot plate 52a to move/slide parallel to the base 52d of the foot support 52.

-21 The leg support 54 has a first supporting apex structure 53(1) and a second supporting apex structure 53(2). A first attaching apex structure (not visible) is attached to the first supporting apex structure 53(1) at a first pivot joint (not visible) The second attaching apex structure 52b(2) is attached to the second supporting apex structure 53(2) at the second pivot joint 53a(2) (a bush and pin receptacle).

The second support structure 53(2) (the support structure nearest the motor) also has a guard piece 53b encapsulating a half-moon gear (not shown) of the second attaching structure 52b(2).

The second support structure 53(2) is attached to the side wall of the leg support 54 by two dove joints 53c.

A control panel 56 is also provided to control the movement of the rehabilitation device.

Referring to Figure 6, there is shown a side view of a rehabilitation device/apparatus 60 which has a foot support 62, with slideably adjustable moveable foot plate (not visible), and a leg support 64 (with a trough 64a).

The figure shows a foot support 62 with flat base 62d and a side wall 62c(2) extending upwards at 90 degrees to the flat base 62d.

A first attaching apex structure (not visible) is attached to the first supporting apex structure 63(1) at a first pivot joint (not visible). A second attaching apex structure 62b(2) is attached to the second supporting apex structure (not shown) at a second pivot joint 63a(2) (a bush and pin receptacle). Integral to the second attaching structure 62b(2) is a half-moon gear 62f.

In use, a motor 69 powers the rotary movement of a pinion 69a, causing the cogs of the pinion 69a to engage with the cogs of the half-moon gear 62f.

Referring to Figure 7, there is shown a rehabilitation device/apparatus 70 which has a foot support 72, with a slideably adjustable moveable foot plate 72a and a leg support 74.

The foot support 72 has a flat base 72d and extending upwards at 90 degrees to the base 72d, two side walls - a first side wall 72c(1) and a second side wall 72c(2). A first attaching structure 72b(1) extends up from, and parallel to, the first side wall 72c(1) and a second attaching structure 72b(2) extends up from, and parallel to, the second side wall 72c(2).

The leg support 74 has a first supporting apex structure 73(1) and a second supporting apex structure 73(2). The first attaching apex structure 72b(1) is attached to the first supporting apex structure 73(1) at a first pivot joint 73a(1) (a first bush and pin receptacle). The second attaching apex structure 72b(2) is attached to the second supporting apex structure 73(2) at the second pivot joint 73a(2) (a second bush and pin receptacle). This allows the foot support 72 to move pivotally around the pivot joints 73a(1) and 73a(2) in order to provide controlled movement to the ankle (not shown).

The slideably adjustable moveable plate 72a has a heel support 75, which may act as an ankle/heel rest.

In the example shown the leg support 74 has a trough 74a (e.g. a concave upper surface of the leg support) to support the TSF frame 80 in use.

A control panel 76 is also provided to control the movement of the rehabilitation device.

A typical method of operating the device illustrated in Figures 1 to 7 will now be explained.

The device is firstly fitted to the patient. This involves placing the lower leg in the leg support and the foot on the moveable plate. The retention straps are used to firmly attach the foot to the moveable plate and the lower leg to the upper surface of the leg support. Advantageously the device/apparatus of the present invention can be fitted to a patient while they are standing, sitting or while they are in bed (e.g. sitting up in bed or lying in bed).

The device is then turned on and a mode selected using one of the mode buttons (warm up, intermediate or full running cycle). Which mode is selected depends on variables such as whether this is the patient’s first time on the device and how far through their physiotherapy session they are.

-23The time for the treatment is then selected (between for example 1 minute to 60 minutes). The speed of the rotation of the foot support about the pivot point is then selected (e.g. the rotational speed, for example from about 0.5 degrees per second up to about 20 degrees per second). The maximum dorsiflexion and plantar flexion is then set. These extreme limits of dorsiflexion and plantar flexion are individual to each patient and are dependent on multiple factors such as severity of injury, and how far through the physiotherapy program the patient is. Advantageously the setting of these maximum limits ensures that the patient’s ankle is not over rotated. Finally the start button is pushed for a minimum of, for example, 2 seconds to initiate the program. The treatment will then run between the maximum dorsiflexion and the maximum plantar flexion at the specified speed and for the specified time.

Claims

1. A rehabilitation apparatus, comprising:

a foot support and a leg support;

wherein the foot support is pivotally attached, by way of at least one pivot joint, to the leg support; and wherein the rehabilitation apparatus further comprises:

a moveable foot plate mounted on the foot support; and a motor adapted to control the degree of pivotal motion of the foot support in relation to the leg support about the at least one pivot joint.

2. The rehabilitation apparatus according to claim 1, wherein the foot support comprises a base and at least one side wall comprising at least one attaching structure.

3. The rehabilitation apparatus according to any preceding claim, wherein the leg support comprises at least one support structure and the foot support is pivotally attached to the at least one support structure of the leg support.

4. The rehabilitation apparatus according to any preceding claim, wherein the foot support comprises first and second attaching structures, the leg support comprises first and second supporting structures and wherein the first attaching structure is pivotally attached, by way of a first pivot joint, to the first support structure and the second attaching structure is pivotally attached, by way of a second pivot joint, to the second support structure.

5. The rehabilitation apparatus according to any preceding claim, wherein the at least one pivot joint is self-lubricating.

6. The rehabilitation apparatus according to any preceding claim, wherein the moveable foot plate is adapted to move parallel to the base of the foot support.

7. The rehabilitation apparatus according to any preceding claim, wherein the moveable foot plate is mounted on the foot support by way of at least one slot recessed into the at least one side wall.

8. The rehabilitation apparatus according to any preceding claim, wherein an upper surface of the leg support is flat or comprises a curved recessed portion.

9. The rehabilitation apparatus according to any preceding claim, wherein the moveable foot plate and/or the leg support comprises at least one retention strap.

10. The rehabilitation apparatus according to any preceding claim, wherein the moveable foot plate and/or leg support further comprises a support cushion constructed from plastic, foam or gel.

11. The rehabilitation apparatus according to any preceding claim, wherein the moveable foot plate further comprises a heal support.

12. The rehabilitation apparatus according to any preceding claim, wherein the motor adapted to control the degree of pivotal motion of the foot support further comprises at least one gear.

13. The rehabilitation apparatus according to claim 12, wherein the motor is a programmable stepper motor.

14. The rehabilitation apparatus according to any preceding claim, wherein the device further comprises a control panel comprising an emergency stop.

15. The rehabilitation apparatus according to any preceding claim, wherein the foot support, leg support and/or moveable foot plate are additive layer manufactured.