GB2311217A

GB2311217A - Therapeutic mattress overlay

Info

Publication number: GB2311217A
Application number: GB9605722A
Authority: GB
Inventors: Robert John Dudley Welch
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-03-19
Filing date: 1996-03-19
Publication date: 1997-09-24
Anticipated expiration: 2016-03-19
Also published as: GB2311217B; GB9605722D0

Abstract

A therapeutic mattress overlay (1)comprising a plurality of laterally extending resilient cells (3,4,5) filled with a supportive material, said cells being conjoined along their lateral edge(s) to adjacent cell(s) to form a mattress overlay. The cells (4,5) of a limb support portion have a dimension significantly smaller than the cells (3) of a torso support portion. The limb support portion is provided in the form of at least two separate plies relatively displaceable from a first position generally in register, to a second position, as shown wherein one of said plies is folded upon itself to increase the total depth of mattress overlay. The cells of the limb support portion can have an arcuate contact surface on one or both surfaces of each ply which acts to retain a folded ply in position when body weight is applied. The cells may be fibre, foam or fluid filled. They may be air filled and subjected to cyclical inflation/deflation.

Description

THERAPEUTIC MATTRESS OVERLAY The present invention relates to a therapeutic mattress overlay, and particularly to such an overlay with a torso support portion having a different configuration from that of the limb support portion. The invention seeks to provide a therapeutic mattress overlay which combines the requirements of reversibility with a requirement that the torso support portion requires a different cell configuration from that of the limb, particularly the leg support portion.

The applicant currently sells therapeutic mattress overlays under the trade name Bodypillo (registered trademark). Such an overlay comprises a plurality of laterally extending resilient cells filled with a supportive material, said cells being conjoined along the lateral edges to an adjacent cell to form a mattress overlay. In a particularly preferred embodiment each laterally extending cell has a depth of about 12.5cm and a width of about 7.5cm. These cells are conjoined to adjacent cells such as to avoid as far as possible creation of "gullies" between the two which can be a collection point for moisture and can lead to higher point loading on adjacent tissues.

Therapeutic mattress overlays are used, particularly in care of the elderly, in order to guard against the creation of pressure sores which are due to pressure and moisture.

When a patient sits in bed areas of high pressure are created particularly under the trochanter and across the shoulders.

The pressure generated between the body and mattress overlay can be sufficient to occlude the capillaries and lymph vessels thereby preventing the circulation of oxygen and nutrients to the skin. Further, air will tend to cease to flow over these areas because of the close contact of the skin with the mattress. This leads to greater amounts of moisture being excreted in order to dissipate heat and waste. Over a period of time a combination of higher pressures and moisture generation lead to the creation of pressure sores.

An attempt has been made in US-A-5,172,439 to address this problem. This disclosure provides a therapeutic mattress overlay comprising a first layer of a resilient foam material, a separable second layer of resilient material maintained generally in laminar juxtaposition to set first layer during use of bed, said second layer being foldable to provide an area of increased thickness to support an anatomical body region, and the third layer of resilient materialdisposed generally in laminar juxtaposition to the second layer and attached thereto whereby the first, second and third layers are portions of a common piece of resilient material.

Difficulties however arise with arrangements of this type which are essentially cut from a single sheet of foam material. In particular gentle movements of the patient, in the sitting up position for example, tend to cause rolled foam to unfurl in use and this is particularly so with the patient in the semi-sitting position.

The applicants have also found that the support of the limb of patients, for example the foot or leg is improved in terms of pressure signatures if the leg is supported on a plurality of arcuate contact surfaces having a relatively small diameter. This is because although there is in such arrangements a small increase in the pressure signature due to point loading, this is more than offset by the ability of air to reach underside of the limb and furthermore, with the exception of the most seriously ill, most patients tend to move their limbs on a regular basis. The applicant has found therefore that the most efficient reversible mattress overlay comprises a torso support portion having relatively larger cells without significant gullies therebetween, and a limb support portion with relatively smaller arcuate contact surfaces. The limb support portion can therefore be made relatively thinner by for example one half of the depth of the torso portion thereby allowing a mattress to be formed of uniform thickness while the limb support portion is bificated so that it may be used either flat in the form of a traditional mattress but with contact surfaces of a different configuration, or maybe utilized by folding the lower or upper ply of the limb support portion upon itself to increase the thickness of the mattress at a predetermined point.

It will be appreciated that the configuration of the limb support portion is preferably arcuate on both upper and lower faces of each ply so that when folded back on itself the arcuate faces interlock with adjacent mattress surfaces to prevent slippage during small voluntary or involuntary movements of the patient.

Accordingly therefore to the first feature of the present invention there is provided a therapeutic mattress overlay comprising a plurality of laterally extending resilient cells filled with a supportive material, said cells being conjoined along their lateral edge(s) to an adjacent cell to form a mattress overlay, characterised in that the cells of a first limb support portion have a dimension significantly smaller than that of the cells of a torso support portion and in that the overlay constituting the limb support portion is provided in the form of at least two separate plies relatively displaceable from a first position generally in register, to a second position wherein one of said plies is folded upon itself to increase the total depth of mattress overlay.

In a preferred form of the invention the adjacent cells of the torso portion are formed to avoid creation of gullies between adjacent cells. The adjacent cells of the limb support portion preferably have an arcuate contact surface on one or both surfaces of each ply. The arcuate surfaces may have a configuration such as to retain a folded ply in position when body weight is applied. The cells are preferably covered with a washable fabric which may be moisture resistant but vapour permeable. The support material is preferably a synthetic fibre or synthetic foam pieces.

The invention will now be described, by way of illustration only, with reference to the accompanying drawings where Figure 1 shows a side view of a mattress in accordance with the present invention with a side portion of the cover open.

Figure 2 shows a side view of the mattress in accordance with the present invention with the cover removed and folded for limb support, and Figure 3 shows a side view of the mattress in accordance with the present invention with the cover removed and adapted for trochanter support.

With reference particularly to Figure 1 a mattress overlay (1) is formed of a plurality of torso support cells (3) which extend laterally for about 90cm. Each cell is formed by a pocket of flexible, slightly resilient, woven fabric filled in this case with swiss-rolled hollow core fibre (6). A suitable woven material may be cotton although other synthetic materials will suffice.

Each cell (3) has in this case a depth of about 12.5cm and a width of about 7.5cm. Adjacent portions of the cell are sewn together at at least two laterally extending positions so that the creation of any significant gully between adjacent cells is avoided.

This torso support portion has been utilized before and found satisfactory for the support of the torso portion of a body by a therapeutic mattress overlay.

In accordance with the present invention there are also provided two plies of limb support cells. The upper limb support cells (4) are similarly formed with a cotton or other synthetic woven material that are filled with foam crumb (14) and have an arcuate contact surface on their upper and lower surfaces. The cells (4) and similarly the cells (5) because the mattress is reversible, extend laterally for the full 90cm but have a depth of about 6.5cm and a width of about 3.Scm.

As is shown in Figure 1 the mattress is surrounded by a vapour permeable but water resistant material such as that sold under trademark Aquavent. The cover is zipped along its longitudinal edge as shown in Figure 1. The cover (2) is not shown in Figures 2 or 3 where it has been removed for simplicity.

In Figure 2, a patient (8) is shown recumbent with his trochanter lying on the torso support portion (3) of the mattress overlay (1). The patients' leg (10) extends over the limb support cells (4) and terminates in a foot (12) with a heel (16). Shown diagrammatically at the foot of the heel (16) is a heel sore (11).

As will be observed the upper limb support cells (4) still support the leg, but the depth of the mattress is increased by the folding back of the lower limb support cells (5). It will be observed that the arcuate contact faces (7) of the upper and lower limb support cells tend to interlock when subjected to the body weight by the leg (10) such that wriggling of the leg or movement of the patient up and down the mattress overlay will not tend to dislodge the upper and lower limb support cells (4 and 5 respectively) so that unfurling is prevented.

By this means air circulation about the heel sore (11) is maintained. By virtue of the arcuate contact surface in contact with the underside of the leg (10) air is able to penetrate under the leg such that moisture is in practice carried away without creating more retained moisture and generating a further pressure sore.

With reference to Figure 3 the patient is shown in a semirecumbent position with his trochanter (9) in contact with the body contact surface of the torso support cell (3). The patients' body (8) is supported on a backrest (15) which in turn is secured to bedhead (13). In other respects like parts are denoted by similar numbers as in Figures 1 and 2.

In this particular embodiment however the lower limb support cells (5) have been folded back on themselves such that the last two elements (5) all of which are filled with foam crumb, are inserted beneath the last of the torso support cells (3).

This causes the torso support cell (3) and hence the adjacent cell (3) to raise up a little thereby preventing the patients' trochanter (9) from sliding downwardly. As can be seen by Figure 3, which represents the arrangement as the patient initially takes up position on the mattress overlay, the action of the trochanter on the last two of the torso support cells will cause these to move very slightly away from the bedhead (13). This has the effect of causing a small amount of re-orientation of the cells (5) such that they interlock with each other because of their arcuate contact surfaces.

Similarly the underside of the limb support cells (4) become interlocked with the uppermost surfaces of the cells (5).

This causes a locking action between the three layers so formed which ensures that after an initial "bedding-in" movement the patient will be supported despite voluntary and involuntary movement.

It will also be observed that the heel portion (16) secured is resting upon an arcuate support surface of the upper limb support cell (4). Because the heel is relatively hard, and the arcuate support surface (4) is relatively small in diameter, pressure sores are not created as might have been thought, essentially because although pressure is created, moisture and heat are readily removed.

Accordingly the present invention provides a therapeutic mattress overlay.

It will further be appreciated that although the cells of the present invention are static in that they are filled with foam crumb or a swiss-rolled fibre an active overlay may be provided by causing a fluid such as air to enter the upper limb support cells (4) or the lower limb support cells (5) and indeed the torso support cells (3). If this happens on a constant pressure basis the overlay thereby forms an air mattress. If the air is applied to the cells on a pulsating basis it causes the cells to inflate and deflate according to a regular cycle so that pressure is transferred from one portion of the torso or limb to another adjacent portion on the successive basis. Means for doing this are well known in the art of airbed technology.

Claims

1. A therapeutic mattress overlay comprising a plurality of laterally extending resilient cells filled with a supportive material, said cells being conjoined on a lateral edge(s) to an adjacent cell to form a mattress overlay, characterised in that the cells of a first limb support portion have a dimension significantly smaller than that of the cells of the torso support portion and in that the overlay constituting the limb support portion is provided in the form of at least two separate plies each relatively displacable from a first position generally in register, to a second position wherein one of the plies is folded upon itself to increase the total depth of the mattress overlay.

2. An overlay according to Claim 1 wherein the adjacent cells of the torso support portion are so formed as to avoid the creation of gullies between adjacent cells, and wherein the adjacent cells of the limb support portion have arcuate contact surfaces.

3. An overlay according to Claim 2 wherein the arcuate surfaces have a configuration such as to retain a folded ply in its folded position when bodyweight is applied.

4. An overlay according to any preceding Claim wherein the mattress is reversible and wherein either ply of the limb support portion may be positioned lowermost and may be folded for retention under the near end of the torso support cells thereby to raise the torso support cell at a point juxtaposed the trochanter of a seated patient.

5. An overlay according to any preceding Claim wherein the cells are covered with a washable fabric and wherein the support material is a synthetic fibre or foam pieces. Amendments to the claims have been filed as follows 1. A therapeutic mattress overlay comprising a plurality of laterally extending resilient cells filled with a supportive material, said cells being conjoined on a lateral edge(s) to an adjacent cell to form a mattress overlay, characterised in that the cells of a first limb support portion have a dimension significantly smaller than that of the cells of a torso support portion and in that the overlay constituting the limb support portion is provided in the form of at least two separate plies each relatively displacable from a first position generally in register, to a second position wherein one of the plies is folded upon itself to increase the total depth of the mattress overlay.

2. A therapeutic mattress overlay according to claim 1 wherein the cells of the limb support portion have substantially arcuate contact surfaces.

3. A therapeutic mattress overlay according to claim 1 or 2 wherein cells of the limb support portion have an interlocking exterior configuration such as to retain a folded ply in its folded position when bodyweight is applied.

4. A therapeutic mattress overlay according to any preceding claim wherein the mattress is reversible and wherein either ply of the limb support portion may be positioned lowermost.

5. A therapeutic mattress overlay according to any preceding claim wherein one of said plies of said limb support portion may be folded for retention under a near end of the torso support portion thereby to raise a section of the torso support portion at a point juxtaposed the trochanter of a seated patient.

6. A therapeutic mattress overlay according to any preceding claim wherein the laterally extending resilient cells are covered with a washable fabric.

7. A therapeutic mattress overlay according to any preceding claim wherein the supportive material is a synthetic fibre or foam pieces.

8. A therapeutic mattress overlay according to any preceding claim wherein the supportive material is a fluid.

9. A therapeutic mattress overlay according to claim 8 wherein the fluid is air and wherein the air is provided on a pulsating basis.

10. A therapeutic mattress overlay substantially as hereinbefore described with reference to the accompanying drawings.