INTRODUCTION

The present invention relates to

BACKGROUND OF THE INVENTION Many elderly people need assistance with their feet and/or lower legs. For example, poor blood circulation or diabetes may cause wounds, which require frequent medical attention, cleaning, or changing of dressing etc. Other elderly persons (from here on referred to as "patient(s)") need putt on supportive stockings in order to avoid collection of water in the lower legs. Leg and foot care as well as putting on supportive stockings are often carried out by home nurses or special wound nurses. Often, the nurse has to lift the leg into the desired position and to support it in that position during treatment or when putting on the supportive stocking.

For a patient of "normal weight" each leg accounts for approximately 15% of the total body weight and one leg may often weigh 12 - 15 kg . Therefore, manual lifting of a leg and maintaining or supporting it in the desired position during treatment exerts a severe strain on the nurse's or carer's body. The strain is often increased due to awkward working postures, as the patient is normally receiving treatment either sitting in a chair or lying in bed . This means that the nurse has to bend forwards or sit stooped for long periods of time, as treatment of for instance a shin wound caused by diabetes can easily take IV2 - 2 hours or more.

For this reason, a number of assistive products are available. One example is support frames made of steel tube. Most have a small "hammock" style cradle of cloth, where the patient's foot or leg rests during treatment. However, the carer still has to lift the leg manually into position in the cradle.

Another example is the so-called leg slings for patient lifters. The sling is a piece of cloth with a loop at each end . The sling is pushed underneath the leg of the patient, the loops are placed in hooks on the spreader bar of the lift and the motor on the lifter is subsequently used to both lift the leg into the desired height and to maintain the leg in that position during treatment. The

disadvantages of this solution are many, the principal one being that only a few of the patients who need foot/leg care happen to have either a mobile person lifter or a ceiling lifter in their homes. Furthermore, the spreader bar and the sling are often in the way, making treatment cumbersome.

Both lifters and support frames are difficult to store for the user or difficult for the caregiver to bring to the patients' homes, as they tend to take up a lot of space and/or be too heavy to carry. For this reason, the known assistive products for foot/leg care are seldom used . Instead, the home or wound nurses lift and hold the legs manually or improvise using whatever is available like small stools, pillows or the like. This way of working is both inefficient, time consuming and dangerous due to a poor work environment.

A number of relatively light lifting apparatuses using air to lift are available.

These products are easy to carry and to bring to the desired place of use. The known products are used to lift persons, who have fallen onto the floor. They all use air to inflate a lifting cushion consisting of a number of air chambers. Such systems are much lighter than traditional mechanical constructions with

motorized lifting . In order to lift a fallen person, the deflated cushion is placed underneath the person or the person is transferred onto the empty cushion. The person then sits or lies on top of the cushion as the air chambers are inflated, normally assisted or supported by a caregiver.

A number of different apparatuses lifting with air can be seen in e.g . GB2462232, US2009/0064417 & US2007/0028388. As the lifting systems described in the quoted documents are used to lift "entire" persons, the systems must by definition be relatively stable to avoid the person being lifted losing his/her equilibrium during the lifting process. As air cushions are notoriously unstable until fully inflated, the known systems inflate a sequence of smaller air chambers, one after the other. In this way, a fallen person may be lifted to the desired height of for instance 60 cm in 4 steps of 15 cm . Limiting the height of each air chamber, reduces the instability to a manageable level .

However, the use of individual air chambers means that fairly comprehensive and complicated pumps, tubes and valve systems must be applied . As a result, the known air lifting systems are unnecessarily expensive. Furthermore, the complexity make the known air lifting systems too complex to operate for most carers and most elderly people, especially for those, who are technically inept and/or suffering from dementia.

The majority of all leg and foot care procedures take place with the patient either sitting on a chair, on the side of the bed or lying in bed - either on the back or on the side. As the treatment of e.g. a shin wound often takes IV2 - 2 hours, it is important to support the patient's leg correctly in order to secure both patient comfort and to maintain a good blood circulation. The correct lifting height will vary substantially depending on whether the patient for instance is sitting in a chair or lying on his/her side in bed. This makes it close to impossible to design a lifting cushion consisting of a number of air chambers, which can achieve all the different desired heights by adding the heights of a given number of fully inflated chambers. Fully inflated chambers are needed to obtain the required stability and rigidity to perform leg/foot treatment.

One more disadvantage of the known air lifting systems makes them unsuited for use in leg/foot care: The individual air chambers have to be welded or glued together. This invariably creates folds and/or openings, where blood, tissue, pus, bacteria etc. may be collected. This results in a high risk of cross contamination, if the air lifting system is used to treat wounds on different people's legs/feet.

Because of the disadvantages described above, the known air lifting systems are not ideal for use in foot/leg care and are very seldom used for this. SUMMARY OF THE INVENTION

It is an object of embodiments of the invention to improve existing devices for lifting during foot or leg care.

In a first aspect, the invention provides an inflatable lifting cushion shaped as a polyhedron where the distances between at least 3 pairs of opposing and parallel faces are between 20 and 60 cm, such as between 20 and 50 cm; and an electrical air pump for inflating the lifting cushion;

Surprisingly, the present invention shows that by designing an inflatable lifting apparatus shaped as a polyhedron based on the interrelationship of the sizes of the human femur, the human tibia and the human pelvis, the ideal lifting heights for treatment of feet/legs can be achieved - irrespective of whether the patient is sitting up or lying on the back/side. Surprisingly, the same polyhedron has proven equally suitable for men and women.

In order to lift the patient's leg to the right height, when he/she is sitting on a chair or on the side of the bed, the desired lifting height is defined by the height of the seat or mattress. The seat height of normal chairs is 43 - 52 cm as is the lowest height of the mattress of most long-term care beds. In order to maintain a comfortable angle when sitting with one leg lifted, a lifting height around 47- 48 cm seems ideal. As can be seen below, 48 cm happens to be the average length of the male femur.

If the patient to be treated is lying in bed on his/her back, the ideal lifting height to support the lower leg is defined by the length of the femur. The average length of the human femur is 46,25 cm (Male average is 48 cm, female average is 44,5 cm. Normal range is 37,5 - 52,5 cm). Allowing for the leg proper, a lifting height around 40 cm seems ideal for a patient lying on his/her back. If the patient to be treated is lying in bed on his/her side, the ideal lifting height to support the lower leg is defined by the width of the pelvis minus the offset of the leg . The average pelvis is approx. 41,5 cm wide, and the offset of the leg around 10 cm. This indicates that ideal support-height for the leg when lying on the side is around 30 cm .

By providing an inflatable polyhedron - in one preferred embodiment in the shape of a cuboid (shown I figure 1 to 7) - with the approximate measurements of 30 x 48 x 40 cm, a simple turning of the cuboid will guarantee that the leg to be treated is always lifted to and supported at the proper height - from small women to tall men. It is obvious that the ideal measurements may vary +/- 15 - 20% depending on ethnicity or race of the patient.

Accordingly, the polyhedron may particularly be a hexahedron having a size in the range of 20-36 cm on one side, 38-50 cm on another side and 32-48 cm on the last side, such as within the ranges of 26-34*42-50*36-44. If a patient has a wound situated on the foot, heel and/or ankle, the leg still needs to be lifted to and supported at the right height, but the entire foot needs to be accessible for treatment. This means that at least one dimension of the cuboid must be inferior to the average length of the human tibia (see Fig. 3). The normal human tibia is 44 - 47 cm long. If the cuboid or polyhedral

described above is turned in the right way, the patient's leg can be positioned in the ideal height, even if the foot has to protrude for treatment.

It is logical that more than three different treatment situations exist and therefore by deduction that additional or different lifting heights can be achieved by using various types of inflatable polyhedrons - for instance tetrahedrons, cubes, octahedrons, dodecahedrons, icosahedrons etc. (not shown) Other logical shapes to use include triangular and pentagonal prisms both regular and irregular (not shown). Finally, cylinders and cones (not shown) may also be used, but are likely to be less stable than necessary. By having only one polyhedral-shaped air chamber to fill, complicated tube-, pump- and valve systems may be avoided making the invention both cheaper and significantly easier to operate. By using an electrical pump, which can both inflate and deflate, the user controls can be kept very simple and easy to understand. Push either "Inflate" or "Deflate" and the pump keeps on going and stops automatically either when a predetermined maximum pressure has been achieved in the air chamber or when all air has been sucked out of the air chamber.

In one embodiment, the cushion is configured automatically to release air when a reference pressure is released, e.g . a pressure which corresponds to a weigh of more than 80 kg. acting on the cushion or a weight of more than 70 kg . or more than 60, 50, 40, 30, or even as little as 20 kg . acting on the cushion. In one embodiment, the cushion is configurable to allow setting of such a reference pressure. The reference pressure may e.g. be utilized for preventing wrong usage of the cushion and thereby to increase safety. As an example, the reference pressure may effectively prevent use of the cushion e.g . for lifting other things than the limb which it is intended to support.

In one embodiment, the pressure is varied during the treatment to thereby obtain a dynamically changing pressure against the limb. Although the single air chamber of the invention is relatively large, it was found that the application of a fine mesh of intertwined lamellae welded between each pair of opposite faces on the cuboid, secured an amazing stability during the inflation process. In this way, wobbliness can be complete avoided .

Furthermore, by having only one chamber in the invention, external folds and creases, where dirt and bacteria may collect, are avoided . By using modern radio frequency welding techniques, nearly all welding seams can be kept on the inside of the air chamber, optimizing hygiene and ease of cleaning / disinfection even further. For the patient to be able to prepare for treatment before the arrival of the nurse - which can save precious time - the system must not only be easy to operate. The system must also make elderly, technically inept and/or dement patients capable of choosing the right lifting height. Trials have shown that whereas many dement elderly patients have difficulties relating to written instructions on the lifting cushion or in a manual, most found it easy to relate either to illustrations or to color-coding on the lifting cushion.

In a second aspect, the invention provides a method for lifting and holding a human limb, the method comprising providing a lifting cushion shaped as a polyhedron, the cushion being provided with distances between at least 3 pairs of opposing and parallel faces between 20 and 50 cm; the method further comprises arranging the cushion under the limb and inflating the cushion.

During treatment, the pressure in the cushion may be determined and adjusted if needed . Particularly, the pressure may be controlled depending on the limb which is supported by the cushion. The pressure may e.g . be compared with a reference pressure during treatment such that air can be released when the pressure is above an upper level reference pressure or additional air can be blown into the cushion when the pressure is lower than a lower level reference pressure. DETAILED DESCRIPTION

In the following, embodiments of the invention will be described with reference to the figures in which :

Fig. 1 illustrates a device according to the invention used by a patient sitting in a chair with one leg lifted; Fig. 2 illustrates a patient sitting in a chair ready to use the invention with one foot resting on a deflated lifting cushion. Fig. 3 illustrates a device according to the invention used to lift the leg of a patient sitting in a chair in a way that makes the entire foot accessible for treatment.

Fig. 4 illustrates a device according to the invention used for lifting the leg of a patient sitting on a bed in a way that makes the lower leg accessible for treatment.

Fig. 5 illustrates a device according to the invention used to lift and hold a leg of a patiently lying on her side in bed .

Fig. 6 illustrates a device according to the invention used with an optional wedge, making it possible to minimize the point of contact

Fig. 7 illustrates another way of using the invention as a tool to help the patient lift her legs into bed.

Further scope of applicability of the present invention will become apparent from the following detailed description and specific examples. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description.

In Fig. 1 one preferred embodiment of the invention is shown, consisting of an inflatable lifting cushion (1) in the shape cuboid where the measurements "A", "B" & "C" define different lifting heights related to the average lengths of the human femur, tibia and pelvis. The lifting cushion consists of one single air chamber, where a fine mesh of intertwined lamellae (not shown) are welded between each pair of opposite faces on the inside of the cuboid to provide stability during inflation. The lifting cushion (1) is inflated and deflated by an electrical pump (2), which is connected to the lifting cushion (1) via a removable air hose (3) and a valve (not shown) in the cushion (1). The electrical pump (2) may be powered via a mains cable (4) supplying 100 - 230 V. The pump (2) may also contain chargeable batteries (not shown) allowing it to be operated where no mains power is available. Inflation and deflation of the lifting cushion

(1) is controlled on a remote control (5) with switches, connected to the pump

(2) with a cable. Alternatively the remote control my operate using wireless communication or the switches may be placed directly on the housing of the pump (2). The 3 pairs of opposite faces on the lifting cushion (1) may be color- coded (for instance with 2 opposing red faces, 2 opposing green faces and 2 opposing blue faces) in order to make it easy for a patient suffering e.g. from dementia to choose the right lifting height by simply remembering, which colour should point upwards.

In Fig. 2 the invention is shown with the lifting cushion (1) deflated and only a few centimetres tall. In this condition, it is easy even for patients with reduced strength in their legs and abdomen to lift the foot onto the deflated cushion and rest it there. By pushing the corresponding button on the remote control (5), the pump will automatically inflate the single air chamber to a predetermined pressure level and then stop. As the inflation progresses, the patient's leg is gently lifted and will come to rest, supported by the lifting cushion (1) as shown in Fig . 1. As the air chamber is inflated, the internal mesh of lamellae will provide stability, until the stability is provided by air pressure, once the cushion (1) is fully inflated and pressurized .

Fig 3 shows the invention in use, where the patient has lifted the leg with the lifting cushion (1) situated underneath the calf, whereby the entire foot is accessible for treatment and the leg still correctly and comfortably supported.

Fig. 4 shows the invention being used sitting on a bed. Figure 5 shows the invention used by a patient lying on her side in bed . The lifting cushion (1) has been turned prior to inflation to fit the approximate width of the human pelvis.

As it is clear from the description above as well as Fig . 1 - 5, the polyhedral lifting cushion is intended to be turned by the patient or carer to choose the optimal lifting height. If the removable air hose (3) is attached to a valve situated on one of the faces of the lifting cushion, the hose could in some instances be caught between e.g . the floor and the cushion proper leading to the airflow being cut off. Alternatively, a patient could find him/herself having to rest his/her leg on top of the valve and/or air hose, which can be painful . If however, the air valve is situated at one of the corners or verteces of the polyhedral lifting cushion, this problem can be fully avoided .

Fig. 6 shows the invention used by a patient sitting in a chair in combination with an optional pillow shaped as a wedge (6). The pillow may - as here - be hard so as to minimize the point of contact between the heel and the pillow leaving the majority of the foot accessible for treatment. Different optional pillows are available from hard foam in wedge shapes to soft pillows full of Kroyer balls (no shown), where the leg/foot sinks into the pillow distributing the contact pressure over a larger area. The bottom of such optional pillows may be made of high friction materials to keep them from sliding on the lifting cushion.

Fig. 7 shows an alternative use of the invention. Many elderly people have not got the strength to lift their legs to the level of the mattress on their own and therefore need assistance to go to bed at night. By placing both legs on the deflated lifting cushion and subsequently activating the pump (2) via the hand control (5), the legs are lifted to the level of the mattress. From this position, most elderly people are capable of turning and lying down in bed . In this way, the invention may help elderly people becoming more independent of outside help.

It should be understood that various changes and modifications of the

embodiment described above may be made within the scope of the present invention. NUMBERED EMBODIMENTS

1. An apparatus for lifting and holding a human limb such as a leg during medical treatment consisting of an inflatable lifting cushion shaped as a polyhedron where the distances between at least 3 pairs of opposing and parallel faces are between 20 and 50 cm an electrical air pump for inflating the lifting cushion

2. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to embodiment 1, where the inflatable lifting cushion is shaped as a cuboid .

3. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the electrical air pump may also deflate the lifting cushion by actively sucking air out of it. 4. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the air pump is powered by mains power and/or rechargeable batteries.

5. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the lifting cushion has a internal mesh of intertwined lamellae welded onto the inside of the faces of the polyhedron to provide stability.

6. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the remote control communicates wirelessly with the pump. 7. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the pump will continue inflation after being activated on the remote control until a predetermined pressure level has been reached inside the lifting cushion or continue deflation after being activated on the remote control, until all air has been sucked out of the lifting cushion.

8. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the remote control is of the "hold-to-run" type. 9. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to embodiment 2, at least 3 pairs of opposing and parallel faces are color-coded .

10. An apparatus for lifting and holding a human limb such as a leg during medical treatment according to any of the embodiments above, where the valve letting air into and out of the the lifting cushion is situated at one of the corners or verteces of said lifting cushion.

11. A method for lifting and holding a human limb such as a leg during medical treatment where an inflatable lifting cushion shaped as a polyhedron where the distances between at least 3 pairs of opposing and parallel faces are between 20 and 50 cm is placed under the foot/leg of the patient

An electrical pump subsequently pumps air into said polyhedral lifting cushion, hereby lifting the leg and maintains the leg in the lifted position for as long as desired .