WO2014167053A1

WO2014167053A1 - Support for therapeutic use

Info

Publication number: WO2014167053A1
Application number: PCT/EP2014/057262
Authority: WO
Inventors: Christian Stephenson
Original assignee: Crawford Healthcare Ltd
Current assignee: Crawford Healthcare Ltd
Priority date: 2013-04-12
Filing date: 2014-04-10
Publication date: 2014-10-16
Anticipated expiration: 2015-10-12
Also published as: GB2515615A; GB201406511D0; GB201306691D0

Abstract

A cushioning device for use in a new method of prophylaxis and treatment, and to a new method of prophylaxis and treatment using the device. The device may be a conformable, flexible and elastic support configured for relieving pressure on and cushioning pressure-sensitive parts of the body, and its new use to protect those parts of the body against oedema. In some preferred embodiments, the support comprises a crosslinked polymethylvinylsiloxane gel material, which may optionally comprise up to 90 wt% of a linear polydimethylsiloxane oil and/or is configured for use on particularly pressure- sensitive parts of the human foot.

Description

Support for Therapeutic Use

The present invention relates to a cushioning device for use in a new method of prophylaxis and treatment, and to a new method of prophylaxis and treatment using the device. It relates more specifically to a conformable, flexible and elastic support with a known use for relieving pressure on and cushioning pressure-sensitive parts of the body, and its new use to protect those parts of the body against oedema.

The lower parts of the body, for example the soles and heels of the feet and the sacrum, tend to be particularly pressure-sensitive parts of the body, where discomfort, pain, haematoma and sores, including pressure sores and/or ulcers and/or other forms of major inconvenience to patients tend to occur, especially in those patients with arthritis, diabetes or cardiovascular conditions who are not bedridden, but may be chairbound. For those who are bedridden, for example with paralysis, other parts of the body, for example on each side of the torso and up to about the middle of the back tend to be pressure-sensitive parts of the body, at risk of discomfort, pain and sores, including pressure sores and/or ulcers. All such pressure-sensitive parts of the body are also prone to developing oedema, which can result in tissue damage

The following description of the present invention is given mainly in relation to supports for relieving pressure on and cushioning pressure-sensitive parts of the body, such as the soles and heels of the feet and the sacrum, and for protecting those parts of the body against major inconvenience, discomfort, pain, haematoma and sores, including ulcers. Such supports are usually shaped to conform in use to the body part to be in direct or indirect contact with the skin of the body part over all areas where the support is used.

However, as noted above, the support of the present invention may suitably be used on other pressure-sensitive parts of the body, for example on each side of the torso and up to about the middle of the back of a patient who is bedridden or chairbound, in particular one who is bedridden, known to be at risk of developing pressure sores and/or ulcers. Because of the number of such pressure-sensitive parts of the body and the relative flatness of some, for example on the back of the patient, which are potentially at risk, the support of the present invention cannot then usefully be shaped to conform in use to the body over a given area. The support is thus not shaped to conform, but to address this problem over all areas, the support is provided in a versatile shape such as an elongate strip, band or ribbon, a quadrilateral, such as a rectangle or oblong, or an equilateral, such as a square.

Reference herein to, or description of, any support shaped to conform in use to the body thus extends mutatis mutandis to supports of the present invention which are conformable, flexible and elastic supports for relieving pressure but are not shaped to conform during use to any required position on the body.

Reference herein to an 'inner face' of a support of the present invention is to the face that in use is in direct or indirect contact with the skin of the human or animal body and conforms in use to the body, and the Outer face' is the opposite face of the support.

It is known that the forms of major inconvenience to patients on the body referred to above can be treated with a pressure-relieving device consisting of a soft conformable support which is often held in position over the affected parts, in the foot by conforming footwear, or in other parts of the body, for example over the sacrum, or on each side of the torso and/or up to about the middle of the back, by pressure-sensitive adhesive around its periphery or on retaining strapping or other appropriate method.

The conformable support is usually made of a soft, almost viscous-fluid-like plastics material, which, for example, can consist of a silicone-based gel or another appropriate elastomer, and is characteristically soft and pliable, and ensures relief of the major inconvenience for the patient. Known supports for the relief of pressure are suitable for the prophylaxis and treatment of the above major inconveniences for the patient, for example in patients who are known to have, or are at substantial risk of developing, them, such as patients with arthritis, diabetes, and so on. Such conformable elastomeric supports for application to a human or animal body do not however provide prophylaxis or treatment of the oedema which potentially affects pressure-sensitive parts of the human body and often accompanies or is a precursor to, for example pressure sores and/or ulcers. Further, whilst known supports relieve pressure on and cushion pressure- sensitive parts of the body, they do not prevent or treat oedema at the pressure- sensitive area.

The structure and/or materials of some such known supports, which in use are in contact with the skin of the human body can be a source of irritation, and can as a result cause or promote oedema at the pressure-sensitive area, resulting in tissue damage, and at worst, create ulcers.

An object of the present invention is thus to provide a conformable pressure- relieving device consisting of a soft conformable support for application to a pressure-sensitive parts of the human or animal body for the prophylaxis or treatment of oedema and underlying tissue damage at those parts of the body. Another object of the present invention is to provide a method of prophylaxis and treatment of oedema and underlying tissue damage at a pressure-sensitive area of the human or animal body comprising the application of a soft conformable support to the pressure-sensitive part. These objects are achieved by the present invention.

Accordingly, in a first aspect the present invention provides a conformable support for application to a human or animal body for the prophylaxis or treatment of oedema associated with pressure on pressure-sensitive parts of the body, which has an elastomeric structure, which in use is in direct or indirect contact with the skin of the human or animal body, where the underlying tissue is at risk of being, or has been, compromised by pressure.

The conformable supports of the present invention may suitably have a thickness of from 0.1 to 5 cm, for example from 0.2 to 3 cm, such as from 0.3 to 1 .5 cm. The thickness may often range between the lowest and highest figures in these ranges where the inner face conforms in use to, for example the arch of the foot, and the support has an increased thickness at the point where it is required to support the arch, or where the inner face conforms in use to, for example the soft tissue over the sacrum, and the support has an increased thickness at that point where it is required to support the sacrum. In both cases, the opposite outer face does not conform in use to the same extent to the relevant part of the human body if at all. The conformable supports of the present invention may suitably be made of a soft, pliable, almost viscous-fluid-like plastics material. Preferably the support is made of a conformable known gel or elastomer of this type.

The gel material, for example, may consist of a silicone-based gel or another appropriate elastomer, for example one based on one or more alkylenes, such as ethylene, propylene and butylene, and styrene and combinations thereof, and thermoplastic polyurethanes, and certain copolyesters and polyamides, and combinations thereof. Suitable silicone-based gel materials include crosslinked polymethylvinyl- siloxanes which may optionally comprise up to 90 wt%, for example up to 60 wt%, such as up to 40 wt% of an oil, for example a silicone oil, for example a linear polydimethylsiloxane . These gels have high durability and a useful level of tack, and are characteristically extremely soft and pliable, and can readily be shaped to conform in use to the body

Suitable elastomers include for example one based on a combination of one or more alkylenes, such as ethylene, propylene and butylene, and styrene, in particular styrene ethylene butylene styrene (SBES), and thermoplastic polyurethanes. These are characteristically extremely soft and pliable,

Where the affected parts are in the human foot or around the human sacrum, the support should be shaped to conform in use to the body over all areas where the support is in direct or indirect contact with the skin of the body. In one embodiment of this first aspect of the present invention, the support is configured for treatment of pressure on particularly pressure-sensitive parts of the human foot. In this embodiment of this aspect of the present invention, the conformable support of the present invention may suitably be foot-shaped, by which is meant that the inner face of the support is shaped to conform in use to the foot over all areas where the support is in direct or indirect contact with the foot. The support typically extends over substantially all of the breadth of the foot, and usually extends upwards over the lower parts of the foot on each side of the foot, and optionally up to about the middle of each side of the foot.

The length that the support may extend over the foot in direct or indirect contact with the foot will depend on the position of the pressure-sensitive affected areas of the foot which the support is required to cushion, and the area over which it is required to spread the pressure from the affected parts of the foot.

Thus, the support may extend over the full length of the foot, or, for example over at least 40 % of the foot, such as over 60 %.

It may extend over the foot from the points of the toes to about the middle of the foot, if the affected part of the foot from which the support is required to spread the pressure is the ball of the foot, often in patients with arthritis, diabetes or cardiovascular conditions.

The support typically extends from behind the heel and below both ankle protuberances and passes forwards under the heel, where the affected part of the foot from which the support is required to spread the pressure is the heel, again often in patients with arthritis, diabetes or cardiovascular conditions.

The support typically extends from the lower back of the heel and below both ankle protuberances and passes forwards under the heel and the arch of the foot, where the support is required both to spread the pressure from and support the arch of the foot, often in patients with arthritis and/or diabetes and fallen arches of the foot. The support may be required to spread the pressure from a combination of such particularly pressure-sensitive affected parts of the foot, again often in patients with arthritis, diabetes or cardiovascular conditions. The configuration of the support required to spread the pressure from those parts will be apparent to the person skilled in the treatment of such conditions.

Outwardly the support may conform to ordinary foot wear (socks, stockings, shoes etc.) worn over it, so that during use, the footwear ensures that the support is held in position and does not shift unintentionally relative to the foot, and the support is urged to conform during use to the required position on the foot.

As noted above, the support of the present invention may suitably have a thickness which varies with the point on the human or animal body to which it is required to support and the degree of support that is required.

The thickness may often range towards the higher figure in the range of from 0.1 to 5 cm where the inner face conforms in use to, for example the arch of the foot, and the support has an increased thickness at the point where it is required to support the arch. This form of therapeutic support is used with advantage by patients with fallen arches.

Similarly, where the affected parts are around the human sacrum, the support should be shaped to conform in use to the buttocks over all areas where the support is in direct or indirect contact with the skin of the buttocks, and where the inner face conforms in use to, for example the soft tissue over the sacrum, the support has an increased thickness at that point where it is required, again towards the higher figure in the range of from 0.1 to 5 cm. Also sheets and strips of the material can also be made to protect the other at risk areas.

In a second aspect of the present invention, there is provided a process for the preparation of the support according to the first aspect of the present invention.

The soft, pliable, almost viscous-fluid-like plastics material of the support in any form or structure is preferably a known gel or elastomer. The gel material, for example, may consist of a silicone-based gel or another appropriate elastomer, for example one based on one or more alkylene, such as ethylene, propylene and butylene, and styrene and combinations thereof.

The process for the preparation of the support according to the first aspect of the present invention is often characterised by the crosslinking of a non-crosslinked precursor of the material of the support according to the present invention, optionally in the course of reactive injection moulding.

In a preferred embodiment of this aspect of the present invention, the support is made of a soft, almost viscous-fluid-like plastics material which consists essentially of a silicone-based gel, and the process for the preparation of the support according to the first aspect of the present invention is then characterised by reactive injection moulding, for example of a room-temperature curing fluid precursor system, such as a high purity catalyst-cure silicone, typically supplied in two parts, with one of the parts containing the catalyst, which are then mixed with any other ingredients which may be required, before injection moulding.

The room-temperature curing fluid precursor system may be based on non- crosslinked polymethylvinylsiloxane, and may optionally comprise a platinum cure catalyst. The mould into which the fluid precursor system, such as a high purity platinum- cure silicone, typically has inner faces that are shaped to conform to the inner face and the opposite outer face of the desired form of the support, and is often in two co-operating parts. This is of course provided that any such precursor, for example of the silicone- based gel or of another appropriate elastomer, is compatible with these pharmaceutically acceptable ingredients, and that any product of the above conventional processes will release them sustainedly to the patient during treatment. In a third aspect of the present invention, there is provided a method of prophylaxis and treatment of oedema at a pressure-sensitive area of the human or animal body comprising the application of a soft conformable support to the pressure-sensitive area.

The applicability of the cushioning device of the present invention for use in a new method of prophylaxis and treatment of oedema at a pressure-sensitive area of the human body is now shown in the following Example.

Example

Silicone heel products were made by mixing the two parts of a two part silicone (polymethylvinysiloxane and silica) polymerisation system (?) [Really need more detail of the system components to ensure sufficiency] and injected in to a heel-shaped mould and left 10 minutes to set.

A 4-week evaluation of the heel product (that is, the above product which is a pad shaped to conform to the human heel) was used on five patients with grade 1 pressure damage to the heel.

Patients with a Waterlow score of 15 or more and pressure injury to the heel(s) of no greater than grade 1 (EPUAP and NPUAP, 2009) were treated for 4 weeks with the above heel product on one heel (the same pad was used throughout the 4-week evaluation, being washed, dried and reused), while the other was treated with the pressure relief usually prescribed.

High frequency diagnostic ultrasound scans were performed at the start and completion of the evaluation in order to capture any subclinical changes, such as the development of oedema (observed as red pixellation), as a result of inflammatory processes relating to grade 1 pressure damage, and to detect any subsequent improvement/deterioration of tissue. Ultrasound scans of undamaged normal skin adjacent to the site of injury served as a control. The ratio of low echogenic pixels (LEP) to total pixel (TP) count (LEP:TP) was used as a measure of dermal water content, enabling oedema, if present, to be quantified. Results These are the interim results for the first cohort of patients completing the 4- week evaluation. At baseline, ultrasound scans of all five heels with grade 1 pressure damage revealed the presence of oedema, seen as a large amount of red pixilation, compared with the large amount of blue pixilation observed in normal skin scans. After 4 weeks of treatment with the product, the damaged heels of all five patients showed improvement and a return to a near normal tissue state, with oedema reduced to a normal level. This was not the case for the standard treatment.

Claims

1 . A conformable support for application to a human or animal body for the prophylaxis or treatment of oedema associated with pressure on pressure- sensitive parts of the body, which has an elastomeric structure, which in use is in direct or indirect contact with the skin of the human or animal body, where the underlying tissue is at risk of being, or has been, compromised by pressure.

2. A support as claimed in claim 1 , characterised by the support comprising a soft, almost viscous-fluid-like plastics material.

3. A support as claimed in claim 1 , characterised in that it comprises a silicone- based gel.

4. A support as claimed in claim 4. characterised in that the gel comprises a crosslinked polymethylvinylsiloxane and optionally up to 40 wt% of a linear polydimethylsiloxane oil. .

5. A support as claimed in claim 1 , characterised by being shaped to conform to a part of the human boy to which it is applied in use.

6. A support as claimed in claim 5, for use on the heel of the human foot, characterised by being shaped to extend in use from behind the heel and below both ankle protuberances and pass forwards under the heel.

7. A support according to claim 5 with a thickness which ranges between 0.3 and 1 .5 cm.

8. A method of prophylaxis or treatment of oedema at a pressure-sensitive area of the human or animal body comprising the application of a conformable support to the pressure-sensitive area.