FORCE-TRANSMISSION-CONTROL SYSTEM AND DEVICES EMPLOYING SAME
FIELD OF THE INVENTION
This invention relates generally to protective bandages, and more particularly to protective bandages including force-transmission-impeding members therein.
BACKGROUND OF THE INVENTION
Protective bandages are used for a wide variety of applications, including the protection of skin grafts, surgical wounds, traumatic wounds, e.g., cuts and abrasions, decubitus ulcers (or prevention thereof) that most commonly form in areas of the sacral, hip, buttocks and elbows. These protective bandages come in a variety of sizes to protect injured skin areas of varying sizes. For example, bandages having a length in the range of 1" to 2" generally are provided to protect blisters and similar skin injuries. Bandages that are generally 3" to 4" in length are commonly employed to protect small surgical incisions of the type that are made in hernia operations and in other minor surgical procedures. Bandages that are 6" to 8" in length, and even longer, are employed to protect larger incisions that are made in connection with major surgical procedures, e.g., back surgery and heart related surgeries. Bandages employed to protect surgical incisions generally are in the range of 2" to 3" wide.
Common prior art protective bandages generally include an inner gauze or other protective layer or member surrounded by an adhesive layer. The gauze or other protective member is placed over the area of the skin to be protected, and is adhered in that position by the surrounding adhesive layer. While these bandages do protect the injured skin area from direct external contact with other surfaces, forces imposed on the bandage, either compressive or shear, often are transmitted to the inner protective layer and to the underlying injured area. Thus, when an external force is applied to the outer surface of the bandage, that force often is transmitted to the injured area, thereby either re-injuring the area or preventing the area from healing properly.
Although bandages for absorbing forces are disclosed in the prior art, a need exists for improved structures that are more effective in shielding an injured area on a person's skin from external forces, both compressive and shear.
U.S. Patent No. 1,913,928, issued to Kauffman, discloses a device for treating and protecting corns. In this device, a sac-like, hollow-walled body is separated by a space including air or another buoyant fluid therein, such as glycerin. Although the patentee states that the sac-like body has inherent elastic qualities, it is not employed in connection with a protective bandage of the type forming the subject matter of the present invention, hi fact, the sac-like member is placed in direct contact with a person's skin; preferably behind an area to be protected, hi other words, in a preferred mode of the invention the protective member is not placed directly over an area to be protected.
Moreover, the sac-like arrangement disclosed in the Kauffman '928 patent is not believed to be optimum for isolating the skin surface contacted by the sac-like member from shear forces.
U. S. Patent No. 5,170,781, issued to Loomis, discloses several embodiments of a protective bandage, hi the embodiments illustrated in Figs. 1-4, a bubble-type member 120 (or multiple bubbles 120A) filled with air are positioned on the upper surface of a bandage to purportedly provide a cushioning effect. The patentee states that the protective bubbles(s) is (are) filled with air and are disposed only over the region of the bandage including the sterile pad. Although the Loomis construction may be effective to protect a wound against compressive forces, shear forces imposed upon the upper surface of the bandage still will be undesirably transmitted through the bandage to an underlying area of the skin in contact with the protective gauze pad of said bandage.
U. S. Patent No. 5,945,679, issued to Baranitsky, describes an adhesive bandage construction that is intended to dissipate frictional (i.e., shear) forces imposed upon the outer surface of the bandage prior to those forces being transmitted to a protective pad 28. In this construction, the bandage includes a conventional anchoring member 12 that extends beyond sterile pad 28 to provide wings having an adhesive material thereon to thereby adhere the bandage to a person's skin in a conventional manner. In the disclosed structure, a flexible planar body or sheet 20 is positioned on the lower side of the bandage between the anchoring member and the sterile pad to purportedly preclude shear forces imposed upon the anchoring member from being transmitted to the sterile pad. In this construction, the planar sheet 20 is adhered to the anchoring member 12 at the peripheral edges thereof and remains unconnected to the anchoring member over substantially the entire inner surface of the
planar sheet material. In view of the fact that the planar sheet material 20 is physically connected to the anchoring member, any shear force imposed upon the anchoring member will be transmitted to the planar sheet 20, thereby inherently imparting some shear force to the underlying sterile pad 28.
In view of the deficiencies existing with prior art bandages, a need exists for protective bandages of the type that effectively protect the wound from external forces imposed upon the bandage, e.g., compressive forces and/or shear forces.
A particularly acute problem exists in connection with the protection of skin grafts, since such grafts are very slippery when initially applied, and tend to shift if the protective layer of a bandage in contact with the graft is caused to shift as a result of experiencing an external shear force applied to an outer surface of the bandage. In other words, skin grafts often experience movement regardless of the best efforts employed to attempt to immobilize them.
There is a definite need for a protective bandage having particular benefit in protecting skin grafts and also in protecting or preventing the formation of decubitus ulcers. It is to such a bandage that the present invention relates.
OBJECTS OF THE INVENTION
It is a general object of this invention to provide protective bandages that impede the transmission of external forces from the outer surface of the bandage to inner surfaces engaging an injured area of the skin to be protected.
It is a more specific object of this invention to provide protective bandages that impede the transmission of external compressive and shear forces from the outer surface of the bandage to inner surfaces engaging an injured area of the skin to be protected.
It is still a further object of this invention to provide a protective bandage for protecting a variety of skin conditions.
It is still a further object of this invention to provide a protective bandage having desirable properties for protecting skin grafts.
It is yet another specific object of this invention to provide a protective bandage having desirable properties for protecting or preventing the formation of decubitus ulcers.
It is still a further object of this invention to provide a protective bandage that prevents the undesired transmission of moisture, e.g., sweat and urine, from permeating into
the region of the protective layer contacting the skin, and also to absorb moisture or exudate directed through the bandage from a wounded area of a person's skin.
SUMMARY OF THE INVENTION
The above and other objects of this invention are achieved in a protective bandage of the type including an anchoring strip having a protective layer on a lower surface thereof for overlying a desired area on a person's skin and also including an adhesive on the lower surface for attaching the bandage to the person's skin, said bandage including force- transmission-impeding means disposed above the anchoring strip.
In accordance with this invention, a top sheet is adhered adjacent peripheral edges thereof to an upper surface of the anchoring strip to define an internal compartment between the anchoring strip and the top sheet. A compressive, cushioning member is retained within the internal compartment for absorbing compressive forces, and low friction, relatively movable, contiguous surfaces within the internal compartment are spaced from the upper surface of the anchoring strip and are capable of sliding relative to each other to absorb shear, or lateral, forces imposed upon the bandage. hi a preferred embodiment of this invention, the top sheet is a planar mesh fabric that is stretchable in all directions within the plane of the fabric, to thereby stretch under the influence of shear forces imposed upon the fabric. hi the preferred form of this invention, the compressive cushioning member includes a gel-type material having at least some ability to maintain its shape when unexposed to external forces. A preferred gel-type material usable in this invention is sold commercially under the name "GAK" and has gel-like properties permitting it to move under the influence of both shear and compressive forces.
In accordance with one embodiment of this invention, the low friction, relatively movable confronting surfaces include the inner surface of the top sheet and an upper surface of the compressive cushioning member. When the compressive cushioning member includes "GAK" or other gel-type material, it is often desirable to additionally include an outer layer made of thin plastic film or other low friction material, to thereby provide the low friction surface for cooperating with the low friction lower surface of the top sheet.
In a more preferred embodiment of this invention, the force-transmission-impeding means includes, in addition to a first compressive, cushioning member, an additional
member that is freely movable within the internal compartment provided between the top sheet and the anchoring strip. Specifically, this additional member is a free-floating member positioned between the top sheet and an upper, low friction surface of the first compressive cushioning member, and is free to move in all directions within the internal compartment under the influence of external shear forces imposed upon the upper surface of the bandage.
In a preferred embodiment of this invention, the additional member can also be provided with cushioning or compressive materials; provided that outer planar surfaces thereof are of a low friction material to permit easy sliding movement between the additional member and the inner surface of the top sheet and the upper, low friction surface of the first compressive member. In this preferred embodiment, there are two planes in which relative sliding movement takes place to dissipate shear forces. The first plane is between the inner surface of the top sheet and the upper surface of the additional, freely movable member. The second plane is between the additional freely movable member and the upper, low friction surface of the first cushioning member. Moreover, when the additional cushioning member includes compressive material therein, it will cooperate with the first compressive cushioning member to enhance, or provide additional cushioning against normal forces imposed upon the bandage.
Another preferred embodiment of the protective bandage comprises: a compressive cushioning member positioned against the skin for absorbing compressive forces applied against the bandage, wherein the compressive cushioning member comprises a plurality of perforations therethrough to permit passage of fluid from the skin to a first surface of the compressive cushioning member, and wherein the compressive cushioning member comprises a first periphery that can be releasably-coupled to the skin surface; an absorption layer disposed on the compressive cushioning member, wherein the absorption layer comprises a second surface for absorbing the fluid and a third surface comprises a low friction, highly slippable surface; and an outer covering having a second periphery that can be coupled to the first periphery of the compressive cushioning member, wherein the outer covering encloses the compressive cushioning member and the absorption layer therein, and wherein the outer covering comprises an inner surface in contact with the third surface; and wherein the third surface slides against the inner surface to form a force transmission- impeding means that absorbs sheer forces imposed upon the protective bandage.
A method is also provided for controlling where the movement occurs when an external force is applied to an article comprising a plurality of uncoupled layers, wherein each layer has at least one surface that is in contact with an adjacent layer and wherein each surface comprises a corresponding coefficient of friction. The method comprises the steps of: inserting between any two layers of the plurality of uncoupled layers an additional layer having at least one surface that comprises a coefficient of friction less than the coefficient of friction of any one of the surfaces of the plurality of uncoupled layers to form a movement interface between the additional layer and at least one layer of the plurality of uncoupled layers; and applying an external force to the article having a component in at least one plane parallel to any one of the plurality of uncoupled layers, and wherein the application of the external force causes movement between any two layers only at the movement interface.
An article for diverting the energy of an externally-applied force to a predetermined portion of the article is provided. The article comprises: a plurality of uncoupled layers wherein each layer comprises at least one surface that is contact with an adjacent layer and wherein each surface comprises a corresponding coefficient of friction; an additional layer, inserted between any two layers of the plurality of uncoupled layers, having at least one surface that comprises a coefficient of friction less than the coefficient of friction of any one of the surfaces of the plurality of uncoupled layers; and wherein a movement interface is formed between the additional layer and at least one layer of the plurality of uncoupled layers such that the application of the externally-applied force having a component in at least one plane parallel to any one of the plurality of uncoupled layers causes movement between any two layers only at the movement interface.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and many attendant features of this invention will become readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
Fig. 1 is an enlarged isometric view of a first embodiment of a bandage in accordance with this invention;
Fig. 2 is an enlarged sectional view taken along line 2-2 of Fig. 1;
Fig. 3 is an enlarged sectional view taken along line 3-3 of Fig. 1;
Fig. 4 is an exploded isometric view of the bandage shown in Fig. 1 to more clearly illustrate the component parts thereof;
Fig. 5 is an enlarged sectional view similar to Fig. 2, showing an alternate embodiment of this invention;
Fig. 6 is an enlarged sectional view similar to Fig. 3, showing the embodiment illustrated in Fig. 5;
Fig. 7 is an enlarged section view similar to Fig. 3, showing yet another embodiment of this invention;
Fig. 8 is an isometric view of yet another embodiment showing a friction-proof, layered skin-protective bandage;
Fig.9 is an exploded view of the friction-proof, layered skin-protective bandage of Fig. 8 showing edgings on two layers that are partially-broken away;
Fig. 10 is a cross-sectional view of the friction-proof, layered skin-protective bandage taken along line 10-10 of Fig. 8;
Fig. 11 is a cross-sectional view of the friction-proof, layered skin-protective bandage taken along line 11-11 of Fig. 8;
Fig. 11 A is a partial cross-sectional view of one side of the friction-proof, layered skin- protective bandage showing an upper slidable layer with a low-coefficient of friction surface being displaced by an outside force and sliding over an absorption layer also having a low- coefficient of friction surface and showing an edging being compressed that restores the upper slidable layer to its original position;
Fig. 12 shows a top view of the friction-proof , layered skin-protective bandage with the outer covering being opened to permit access to the contents of the bandage;
Fig. 13 is cross-sectional view of another variation of the friction-proof, layered skin- protective bandage depicting a single absorption layer having a low coefficient of friction surface in contact with the plastic film of the gel-type material;
Fig. 14 is a cross-sectional view of still another variation of the friction-proof, layered skin-protective bandage wherein a clear silk-type or other clear wicking-type layer, is positioned between the absorption layer and the plastic film of the gel-type material;
Fig. 15 is a cross-sectional view of the friction-proof , layered skin-protective bandage of Fig. 8 but having a clear silk-type, or other clear wicking-type layer, is positioned between the bottom surface of the gel-type material and the wound/skin;
Fig. 16 is an isometric view of the friction-proof , layered skin-protective bandage of Fig. 8 but having alternative accesses in the outer covering;
Fig. 17 depicts a side view of an exemplary stack of surfaces utilizing the force transmission control system principle and having a stabilizing mechanism that prevents any sliding action until the stack is delivered or is otherwise ready for operation; and
Fig. 18 depicts a side view of another exemplary stack of surfaces utilizing the force transmission control system principle and having an alternative stabilizing mechanism that prevents any sliding action until the stack is delivered or is otherwise ready for operation. DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
Referring to Figs. 1-4, a protective bandage in accordance with this invention is shown generally at 10. Specifically, the protective bandage 10 includes an anchoring strip 12 having a generally centrally located protective layer 14, in the form of a sterile pad on the lower surface thereof, and an adhesive layer surrounding the protective layer 14. The bandage further includes an upper construction 16 disposed on the surface of the anchoring strip 12 opposite the surface including the protective layer 14 and adhesive layer thereon to provide the unique force- transmission-impeding functions in accordance with this invention.
It should be understood that the anchoring strip 12, the protective layer 14 and the adhesive for securing the anchoring strip to a person's skin can all be of a conventional design, and do not form any limitation on the present invention. For example, the anchoring strip 12 can be made of any suitable plastic or fabric material. The protective layer 14 can be made of gauze, absorbent plastic, etc. Any other arrangement of an anchoring strip and protective layer is considered to be within the scope of the present invention.
Turning specifically to Figs. 2 through 4, the upper construction 16 includes a lower compressive cushioning member 18 having a lower surface 20 adhered through a suitable adhesive to upper surface 22 of the anchoring strip 12 to prevent relative sliding movement between the cushioning member and the anchoring strip. Immediately above the lower compressive cushioning member 18 and in contact therewith is a generally pancake-like compressive disc 24 positioned on upper surface 26 of the lower compressive cushioning
member 18 and being of a smaller dimension then the cushioning member so as to be freely slidable in all directions on said upper surface 26.
This compressive disc 24 preferably is round or oval, including curved peripheral edges so as to eliminate sharply defined peripheral edge surfaces that could impede the ability of the disc to slide freely on the upper surface 26 of the compressive cushioning member 18.
In the illustrated embodiment, the compressive disc 24 includes an internal compressive section 28 that can include any desired compressive material such as sheets of tissue, gauze, gellike material and the like. In addition, the compressive disc 24 includes an outer, low-frictioned covering member 30, which can be in the form of a thin plastic film, such as polypropylene, polyethylene or the like, provided that it has a relatively low friction surface for permitting the compressive disc 24 to freely slide in all directions on the upper surface 26 of the compressive cushioning member 18 when exposed to externally-imposed shear forces. In this regard, it should be noted that the upper surface 26 of the cushioning member 18 likewise is a surface of a low-friction material, such as a surface of an outer wrap of plastic film 32, made from polypropylene, polyethylene or the like, hi fact, in the preferred construction, the lowest frictional resistance to sliding movement in the bandage takes place between the compressive disc 24 and the compressive cushioning member 18.
As noted above, in order to permit the compressive disc 24 to freely slide relative to the cushioning member 18, it is constructed of smaller planar dimensions than the cushioning member 18. This arrangement can be seen best in Figs. 2 and 3.
Still referring to Fig. 4, a planar top sheet 34, which preferably has elastic properties in all directions within its plane, is positioned over the compressive disc 24 and its peripheral edges thereof are secured directly to the upper surface 22 of the anchoring strip 12 by a perimeter strip 36 having adhesive on the lower surface 38 thereof. The perimeter strip 36 can be made of the same material as the anchoring strip 12, so as to provide an aesthetically pleasing surface appearance to the construction.
The elastic top sheet 34 can be made of any desired elastic material that is capable of elastically stretching in all planar directions under the influence of shear forces. For example, a nylon mesh fabric of a weave commonly employed in women' s nylon stockings is suitable for use in this invention. The desired thickness of the top sheet 34 can be easily determined by a
person skilled in the art based upon the shear forces that will be encountered during use of the bandage 10, and the nature of the internal components on the upper construction 16.
Turning specifically to Figs.2 and 3 , the lower compressive cushioning member 18 most preferably includes a gel-type material 40 that essentially maintains its shape unless directly exposed to external forces. The gel-type material is capable of moving when exposed to shear or compressive forces to aid in taking up these forces prior to their transmission to the protective layer 14 and underlying protective area of the skin.
In a preferred embodiment of this invention, the gel-type material can be a material sold under the name "GAK". As noted above, in accordance with a preferred embodiment of this invention, the "GAK" or other gel-type material is enclosed within an outer, low friction wrap of plastic film 32 and then adhered through an adhesive layer 42 to the upper surface 22 of the anchoring strip 12. This prevents relative sliding movement between the cushioning member 18, and the anchoring strip 12.
Referring to Figs. 1-3, it should be noted that the top sheet 34 provides the entire outer surface of the upper construction 16; completely confining the cushioning member 18 and the compressive disc 24 within the internal compartment provided between the anchoring strip 12 and the top sheet 34. It should be understood that, although the top sheet 34 is illustrated as being in close conformity with the members within the internal compartment, the top sheet 34 can be adhered to the upper surface 22 of the anchoring strip 12 with some slack.
The construction of the bandage 10 provides a unique cooperation of elements that has not been achieved in prior art constructions. Specifically, in the bandage 10 shear forces are taken up by the relative sliding movement of contiguous surfaces that are spaced outwardly from the upper surface 22 of the anchoring strip 12. In particular, in the preferred construction of this invention, relative sliding movement takes place between the upper surface 26 of the cushioning member 18 and the contiguous surface 44 of the compressive disc 24. As noted above, the least resistance to sliding movement takes place between these latter two surfaces, h addition, relative sliding movement takes place between the inner surface 46 of the top sheet 34 and the contiguous upper surface 48 of the compressive disc 24. hi the preferred embodiments of this invention there is somewhat greater resistance to sliding movement between the top sheet 34 and the compressive disc 24 than between the compressive disc 24 and the compressive cushioning member 18. Thus, in the preferred embodiment of this invention, there are two pairs
of contiguous surfaces that are capable of moving relative to each other to absorb shear forces imposed upon the bandage, and both of these pairs of surfaces are disposed outwardly of the upper surface 22 of the anchoring strip 12. This arrangement should effectively result in the dissipation of shear forces imposed upon the bandage prior to those shear forces being imposed upon the protective layer 14 engaging a protected area of a person's skin.
It also should be noted that at least a portion of the shear forces imposed on top of the sheet 34 can be dissipated by the stretching of the top sheet or by relative sliding movement between the outer surface of the top sheet and the member or surface imposing the shear force thereon. However, in the preferred embodiments of this invention it is expected that the shear forces will be predominately dissipated by the sliding movement between the compressive disc 24 and the compressive member 18, and the sliding movement between the compressive disc 24 and the top sheet 34.
In addition, it should be noted that the use of a gel-type material 40 in the cushioning member 18 provides several functions. First, the gel-type material has excellent cushioning properties, to thereby protect an underlying skin area from compressive forces, hi addition, the gel-type material is capable of laterally extending or stretching, such as a gelatin sold under the trademark Jell-O, to thereby also assist in taking up shear forces, if needed.
By physically attaching the compressive cushioning member 18 to the upper surface 22 of the anchoring strip 12, any shear forces imposed upon the bandage 10 will tend to be dissipated by the relative sliding movement between the compressive disc 24 and both the lower compressive cushioning member 18 and the top sheet 34, since these are the lowest friction sections of the bandage.
Referring to Figs. 5 and 6, a second embodiment of a protective bandage in accordance with this invention is shown at 100. As in the first embodiment of this invention, the protective bandage 100 includes an anchoring strip 12, a protective layer 14 in the form of a sterile pad disposed in the central region of the anchoring strip, and an adhesive layer surrounding the protective layer to attach the bandage to a person's skin.
Also, as in the construction of the bandage 10, the protective bandage 100 includes a top sheet 34 adhered to upper surface 22 of the anchoring strip 12 by a perimeter strip 36.
The bandage 100 differs from the bandage 10 in the arrangement of the internal components of the upper construction 16 for dissipating both compressive and shear forces. It
should be understood that the relative dimensions of the bandage 100 can be varied within the same limits as the bandage 10, and that the sectional views of the bandage 100 illustrated in Figs. 5 and 6 are comparable to the sectional views shown in Figs. 2 and 3 with respect to the bandage 10.
Referring specifically to Figs. 5 and 6, the top sheet 34 cooperates with the upper surface 22 of the anchoring strip 12 to define an internal compartment 50. In this embodiment, a lower compressive cushioning member 118 is provided that differs from the compressive cushioning member 18 employed in the bandage 10. Specifically, the lower compressive cushioning member 118 includes a central core 120 in the form of multiple gauze sheets or other desired sheet material. The central core 120 is confined within an outer plastic film layer 122, which can be of the same plastic employed as the outer plastic wrap 32 in the bandage 10. The outer plastic film wrap 122 provides an upper, low friction surface 124 for purposes to be described hereinafter.
It should be noted that the outer plastic film wrap 122 includes a lower surface 126 that is secured by a suitable adhesive layer 128 to the upper surface 22 of the anchoring strip 12. Thus, this adhesive layer 128 immobilizes the compressive cushioning member 118 against sliding movement relative to the anchoring strip 12.
From the above explanation, it should be understood that the compressive cushioning member 118 is intended to provide a similar function to the compressive cushioning member 18 employed in the bandage 10. However, the cushioning effect of the central core 120 in the cushioning member 118 may not be of the same character as with the use of the cushioning member 18, which includes the gel-type material 40 therein.
Still referring to Figs. 5 and 6, a pancake-like compressive disc 130 is provided on top of the compressive cushioning member 118. This compressive disc 130 can be of the same general dimensions as the compressive disc 24 employed in the bandage 10, so as to permit this compressive disc to slide freely in all directions relative to the compressive cushioning member 118.
As can be seen in Figs. 5 and 6, the compressive disc 130 includes an internal core 132, which can be of the same gel-type material 40 employed in the bandage 10. Specifically, this gel-type material can be "GAK."
When the internal core 132 is formed of "GAK" or other gel-type material that has relatively high-friction surfaces, the compressive disc 130 is provided with an outer, low-friction wrap, such as a plastic film wrap 134. This plastic film wrap 134 can be of the same material as the outer, low-friction covering member 30 in the compressive disc 24.
The compressive disc 130 functions to take up both shear and compressive forces in a manner similar to the compressive disc 24 employed in the bandage 10. However, the compressive properties of the disc 130 are somewhat better due to the inclusion of the gel-type material in the core, as opposed to the gauze type material employed in the compressive disc 24.
It should be noted that the bandage 100 functions in essentially the same manner to take up shear forces as the bandage 10. In particular, when the bandage 100 is exposed to shear forces, the compressive disc 130 is permitted to slide freely in all directions relative to the inner surface of the top sheet 34 and the upper surface of the outer plastic film wrap 122 of the lower compressive cushioning member 118 to thereby take-up the imposed shear forces. In other words, the relative sliding movement takes place between two pairs of contiguous surfaces, both of which are spaced outwardly from the upper surface 22 of the anchoring strip 12.
Referring to Fig. 7, a third embodiment of a protective bandage in accordance with this invention is shown at 200. The protective bandage 200 is of a less preferred construction than the protective bandages 10 and 100, and in particular, does not include any freely movable compressive disc member therein. However, for applications in which the requirements for isolating a protected skin area from shear forces is of a lesser concern, the construction of the protective bandage 200 may be acceptable.
Referring to Fig. 7, the protective bandage 200, like the previously described embodiments, includes an anchoring strip 12, a protective layer 14, a top sheet 34 and a perimeter strip 36 for securing the top sheet 34 to the upper surface 22 of the anchoring strip 12. However, the protective bandage 200 differs from the embodiments of the protective bandages 10 and 100 in that it only includes one member in the interior compartment 202 provided between the top sheet 34 and the anchoring strip 12. That member is a compressive cushioning member 204, which can be of the same construction as the compressive cushioning member 18 in the protective bandage 10. Specifically, the compressive cushioning member 204 can include an internal gel-type core provided with an outer wrap of a low friction plastic sheet material, as is illustrated at 206 in Fig. 7.
An adhesive layer 208 is provided to secure the cushioning member 204 to the upper surface 22 of the anchoring strip 12, thereby immobilizing the cushioning member against sliding movement on the upper surface of the anchoring strip.
In the embodiment illustrated in Fig. 7, the relative sliding movement for taking up undesired shear forces takes place only between inner surface 210 of the top sheet 34 and upper surface 212 of the compressive cushioning member 204. Thus, there is only one pair of surfaces at which relative sliding movement takes place to dissipate shear forces imposed upon the bandage. However, as in the bandage constructions 10 and 100, this pair of sliding surfaces is located above the upper surface 22 of the anchoring strip 12.
It should be noted that in all embodiments of this invention the top sheet 34 preferably is made up of an elastic material that is stretchable in all directions within the plane of the sheet. Thus, any shear forces imposed upon the top sheet 34 will at least be partially taken up by the stretching of the top sheet 34. Moreover, the stretching of the top sheet 34 will take place by the top sheet sliding relative to the contiguous low friction surface of either the compressive disc 24 (bandage 10), the compressive disc 130 (bandage 100), or over the low friction surface of the compressive cushioning member 204 (bandage 200).
If desired, all of the protective bandages within the scope of this invention can be provided with a safe, inert desiccant to absorb moisture. The desiccant can be of any well- known material, such as rice, or a desiccant of the type conventionally used with clothing and other products wherein moisture tends to create a problem.
The desiccant can be included either in the open area in the internal compartment provided between the top sheet 34 and the anchoring strip 12, or, if desired, within the compressive discs 24 or 130 in the protective bandages 10 and 100, respectively. The use of rice as a desiccant is illustrated at 212 in the bandage 10 (Fig. 3).
In many applications, it is highly desirable to prevent moisture, such as sweat and urine exuded by a patient wearing the bandage, from permeating into the region of the protective layer 14 contacting the patient's skin. When the anchoring strip 12 is of an impervious construction, the use of a desiccant may not be necessary . However, for some applications it may be desirable to include a porous anchoring strip into the construction to permit exudate from the wound to pass through the anchoring strip in the internal compartment provided between the anchoring
strip and the top sheet 34. In these embodiments, use of a desiccant to help absorb fluids is highly desirable.
It should be understood that applicant has described the preferred embodiments of his invention; it being understood that, in accordance with the broadest aspects of the invention, a bandage is provided that includes force-transmission-impeding means on the upper surface thereof to absorb or otherwise dissipate shear forces upon the upper surface of the bandage prior to those forces being transmitted to the protective layer 14, wherein such shear forces can further damage or preclude the healing of skin injuries.
Figs.8-16 depict a further improvement of the bandages of Figs. 1 -7. In particular, Figs. 8-16 depict variations in a friction-proof , layered skin-protective bandage 300, hereinafter FLSP bandage 300. This invention 300 basically consists of alternative layered wound dressing with slippable layers, absorbency, gel cushion and special adaptations to allow for keeping the wound and dressing dry and clean.
As shown most clearly in Fig. 9, the FLSP 300 basically comprises a compressive cushioning layer 302 of a gel-type material 304, an absorption layer 306 having a low-friction upper surface 308, an upper slidable layer 310 having low-friction upper 312A and lower 312B surfaces and an outer covering 314.
The gel-type material 304 of the compressive cushioning layer 302 comprises a plurality of perforations 316 that pass through the entire thickness of the gel-type material 304 to allow the absorption layer 306 to absorb fluid from the wound. As shown in Fig. 10, a bottom surface 318 of the gel-type material 304 is positioned directly on a wound 303. The importance of providing a means for fluid to migrate away from the wound is because a wet wound in almost all cases is predisposed to infection and skin maceration. Without the perforations 316 fluid collects under gel-type material 304. Preferably, the gel-type material 304 is clear (e.g., ClearSite® by Conmed Corporation of Utica, New York or other transparent synthetic gel material) for wound examination. Furthermore, the gel-type material 304 is covered by an outer, low friction wrap of plastic film 320 whose periphery 321 includes an adhesive surface 322 that is applied to the skin 301 ; the plastic film 320 also comprises a plurality of perforations 324 to allow passage of fluid into the absorption layer 306. Thus, the FLSP 300 is releasably secured to the wound 303via this adhesive surface 312. The bottom surface 320 of the gel-type material 318 is in direct contact with the wound 303. The wound 303 could even be treated with H2O2
and provodine-iodine (Betadine) to suppress growth of microbes. The perforations 316 and 324 are a very important aspect of the present invention since the use of the gel material 304 directly on the skin 301 or wound 303 without the perforations 316/324 accumulates sweat and wound fluids beneath the gel material 304 which is undesirable.
The absorption layer 306 is positioned on top of the film 320 and may comprise any type of absorptive material, such as gauze or a sponge, etc. Thus, fluids from the wound are able to escape the wound by passing through the plurality of apertures 316 in the gel-type material 304, through the plurality of apertures 324 in the film 320 and then into the absorption layer 306. The upper surface of the absorption layer 306 comprises a low-friction, highly slippable material 308 (e.g., Telfa® by Kendall Company of Mansfield, Massachusetts) that supports the sliding or slipping of another surface thereon.
The upper slidable layer 310 comprises a low-friction, highly slippable material upper surface 312A and a low-friction, highly slippable material lower surface 312B. This construction allows the slidable layer 310 to freely slide in all directions on top of the low- friction, highly slippable material 308 of the absorption layer 306 when exposed to externally- imposed shear forces. Not only does the low-friction material 308 and the low-friction material 312B form a slippable interface, but the low friction surface 312A and the outer covering 314 form another slippable interface. Thus, movement of this slidable layer 310 results in the dissipation of shear forces imposed upon the bandage 300 rather than on the wound 303. addition, a compressible edging 326 (e.g., foam or sponge, etc.) is formed around the edge of the upper slidable layer 310 that acts as a restoring means against the outer covering 314 when the slidable layer 310 is moved. In particular, Fig. 11 A shows one side of the FLSP 300 where the edging 326 is compressed against the outer covering 314; once the external shear force is dissipated, the edging 326 restores to its normal shaping, thereby pushing the slidable layer 310 back to the neutral position shown in Fig. 10. The upper slidable layer 310 may comprise any lightweight material and can be fully enclosed or may just have the upper and lower low- friction, slippable layers 312A/312B.
The outer covering 314 is similar to the covering 34 discussed earlier and preferably has elastic properties in all directions. For example, a nylon mesh fabric of a weave commonly employed in women's nylon stockings is suitable for use as the covering 34. This stretchable covering 314 is fixed on all sides to retain the movable or slippable layers within. The periphery
328 of the covering 314 also comprises an adhesive 330 on its underside which corresponds to the periphery 321 of the plastic film 320. Thus, the outer covering 314 is coupled to the film 320 and not to the skin 301 of the living being, hi addition, to provide access to the contents of the FLSP 300, the upper portion of the covering 314 comprises closure means 332. As shown most clearly in Fig. 12, the closure means 332 basically comprises a vest-over-pants construction wherein an opening 334 is formed in the covering 314 and a first portion 336 overlaps a second portion 338 to cover the opening 334; to gain access to the opening 334, a user pulls the first portion 336 away from the covering 314 and then pulls the second portion 338 from the covering 314 which exposes the opening 334 and allows access to the contents. Thus, the closure means 332 provides for an easily openable and re-closable outer covering 314 at bedside which facilitates changing the absorption layer 306 on a regular basis or as needed.
It should be noted that the absorption layer 306 is shown in Figs.9-11 as having its own edging 340. This edging 340 is optional since the absorption layer 306 does not slide over the plastic film 320. However, this edging 340 provides additional protection if the shear force is directed specifically at the absorption layer 306 alone.
It should be also noted that the upper slidable layer 310 is optional and that the absorption layer 306 with its upper low-friction surface 308 can form the slippable interface with the outer covering 314.
Fig. 13 depicts an alternative to the FLSP 300 wherein a single movable layer 342 is shown, hi particular, the layer 342 comprises an absorption layer (e.g., gauze, sponge, etc.) that comprises upper and lower low-friction, highly slippable surfaces 344A and 344B. Thus, a double slippable interface is formed between (1) the upper surface 344A and the outer covering 314 and (2) the lower surface 344B and the plastic film 320. This construction allows the absorption layer 342 to freely slide in all directions on top of the film 320 when exposed to externally-imposed shear forces. The layer 342 also comprises compressable edging 346. The slippable surface 344B also permits the passage of fluid from the perforations 316 in the gel material 304 and the perforations 324 in the film 320 into the absorption layer 342.
Fig. 14 depicts another alternative to the FLSP 300 wherein a wicking layer 348 (e.g., silk, woman's pantyhose material, nylon, CoolMax® by E. I. du Pont de Nemours and Company, etc.) that is positioned between the absorption layer 306 and the plastic film 320; as mentioned earlier, the upper slidable layer 310 is optional. This wicking layer 348 is porous and
facilitates drawing any fluid away from the wound from the gel material 304 and into the absorption layer 306. In this construction, the slippable interface is formed between the highly- slippable material 308 on top of the absorption layer 306 and the outer covering 314.
Fig. 15 depicts a further alternative to the FLSP 300 which uses both the absorption layer 306 and the upper slidable layer 310 and wherein a transparent, porous layer 350 is positioned between the wound 303 and the bottom surface 318 of the gel material 304. The porous layer acts as a wicking layer and may comprise a transparent form of, for example, silk, woman's pantyhose material, nylon, CoolMax® , etc.
Fig. 16 is similar to the embodiment shown in Figs. 9-15 except that the outer covering 314 comprises a different closure means. In particular, the closure means 332 has been replaced by a dual closure means 352A and 352B located on each side of the FLSP 300. A opening 354 is formed on each side of the covering 314 that provides access to the contents of the bandage 300. An upper flap 356 can be lifted to gain access to the opening 354 and when done, the flap 356 is folded down to cover the opening 354.
Thus, the various protective bandages of the present invention disclosed above provide an "ultimate" dressing in that, among other things,:
1. They provide a sterile wound dressing;
2. They allow gentle gel covering which permits wound examination;
3. They allows for easy changing of the first and/or second layer in order to keep the region clean and dry;
4. They (viz., the gel material 304 therein) protect against vertical force;
5. They protect against parallel or oblique forces because of a "selectable-site-of- slippage rule" which results in slippage occurring only between layers with the least coefficient of friction, thereby obviating shear forces at skin level.
Using the present invention, doctors and nurses will both be quite pleased with such bandages and that timely applied, the bandage of the present invention prevents bed sores beginning and worsening (which is a huge, painful, costly clinical problem), allows for the non- displacement of skin grafts, lowers their infection rate and makes an ideal dressing for any type of hospital-acquired wounds.
In view of all of the above, the importance of the slipping or movement occurring at a predetermined location in the protective bandages 10-300 is based on what Applicant refers to
as a "force transmission " or "selectable-site-of-slippage" rule. In particular, in an attempt to improve the modern wound dressing and skin-protective bandages, from the point of view of how these bandages protect the skin from external forces, Applicant has come upon what he believes to be a corollary or derivative to the law of friction, Faction = μ Fnormai, where FfViction is the frictional force, μ is the coefficient of friction, and Fnormai is the normal force. The parallel component of the force applied to a multi-layered structure creates slippage between the layers where the coefficient of friction is the least (when the coefficient of friction between these two surfaces is overcome), and seems to preclude slippage at the other interfaces and hence the name "selectable-site-of-slippage (SSS) rule". This rule appears to solve the problem of protecting skin (wounds) from the parallel component of force applied. Cushioning the bandage and preventing the patient's weight from being applied directly to the wound appear to be the best ways of diminishing the perpendicular component of the applied force. This effort is directed only to the parallel component of the applied force. There is, however, much yet to be understood about the perpendicular component of the applied force. The invention of these bandages can be adapted for use on the elbow, viz., the olecranon , where friction usually occurs, in the form of pads which, instead of being adhesively coupled to the skin, can be releasably coupled using a band or wrap; a similar pad can be adapted for use at the knee, heels, or hip. The invention of these bandages can be adapted for use at the sacrum.
A clarifying example of the SSS rule is demonstrated by the following: a banana peel is placed on a walkway with the slippery interior of the peel against the walkway; a person steps on the banana peel and both the person and the banana peel are displaced, i.e., both the person and the banana peel are affected by the parallel component of the force applied. Conversely, if the banana peel is placed on the walkway with the slippery interior of the peel facing upwards and the person steps on that surface, only the person is displaced while the banana peel remains in position.
When "bench experimentation" is performed by layering a variety of substances with different coefficients of friction between them, no matter how they are arranged, this SSS rule, holds. In other words, the slippage always occurs at the level of least friction. Furthermore, with any moderate force (as opposed to excessive amounts of force, e.g., enough to displace the entire stack of layers off of a supporting surface), there is no slippage between any other interfacing surfaces, hi addition, according to this observation, it appears that the relative
motion of the two surfaces with the smallest coefficient of friction between them precludes the other interfaces, with liigher coefficients of friction, from overcoming their coefficients of friction and moving relative to one another.
By applying the SSS rule in bandage construction, Applicant has achieved a slippage of bandage (or cloth, or any other matter applied to skin surface) that can be prevented by having a layer with greater slippage elsewhere in a layered bandage, hi the case of a skin graft, where . the undersurface of the graft and the outer surface of the graft site have a very low coefficient of friction, there simply need be an outer layer where the coefficient of friction is even less (e.g., mineral oil applied to standard smooth plastic covering is known to work well). Thus, such layered protective bandages are beneficial for prevention, for example, of knee and elbow frictional injuries, as well as protection of surgical wound, graft sites, and pressure sores. It is within the broadest scope of this invention that there are many ways in which the SSS rule can be used in a protective way and in a wide variety of other circumstances. Furthermore, what is also interesting to note is that by controlling where or which layer slips or moves when exposed to an external force, this in turn fixes the other layers, with the higher coefficients of friction, from moving. Thus, the insertion of the layer also causes a re-direction of heat (caused by friction) away from where it is not desirable to a location where the generation of heat is desirable.
By adding one or more layers to the structure, or a part of the structure, with the result that the precalculated increase or decrease in the two sides of the layer added change the interface at which slippage occurs in a layered structure, or make it the interface with the lowest coefficient of friction, thereby exerting control over the site of slippage or motion and indirectly preventing motion between the other interfaces as well as indirectly determining the force required for slippage or motion. In other words, as a coefficient of friction is selected by selecting a surface, the amount of force that is necessary to put the layer into motion is controlled. And in consequence, because the above can refer to any object in any state or any part thereof, be it a man, a machine a building, a molecule, an atom, etc., and any force, the horizontal component thereof, including all known normal forces, gravity, motion, magnetism, quantum forces, sound and other waves, field forces, and then a question about light, can be used to enhance or decrease the result of the given forces's action on that given item or part thereof with the result of protection, increased damage in the case of a weapon, site and amount
of heat generated by the interaction. Furthermore, by controlling that slippage, uses of the heat, or energy released, can also be controlled. Thus, through the insertion of at least one layer, one can control the slippage site and modulate these forces to achieve useful functions. In addition, besides inserting at least one layer, a further improvement is to include means to return the structure back to its original position after a given force has been delivered.
The SSS rule can be stated alternatively as: Any structure wherein undesirable effects on a man or an object to be changed or desirable effect created, manipulated by any force including gravity, Newton's laws, etc., with the ultimate effect of controlling, relocating, reducing or increasing the end results, all based on the addition or construction with the key extra layer or layers made with surfaces having coefficients of friction so as to gain the desired result and generally following the physics of the SSS rule.
In view of this SSS rule, Applicant believes that the SSS rule has wide application in a variety of fields and is not, in any way, limited to bandages or skin protection. For example, the introduction of at least one layer to divert the movement to a desired portion of an article could be used in helmets, clothing (especially sports clothing where sliding occurs, body suits, gloves), shoes, protective vehicle collision or impact apparatus, conveyor belts, house or building construction (to alleviate wind damage such as that posed by hurricanes, tornadoes, etc.), bedding, furniture, etc. With particular regard to clothing, the application of the SSS rule is especially important in stunt- men's clothing where the diversion of the stunt energy is accomplished with at least one interface of high slippage layers in the stuntman's suit being at a site away from the skin of the stuntman. For sports clothing, such as in football, at least one interface of high slippage layers (away from the skin) in the sleeves of the player's uniform can alleviate friction to the forearms of the players, where friction usually occurs. The application of the SSS rule can be adapted for use in condoms where the condom comprises a double layer construction. In particular, the condom in accordance with the present invention comprises an inner layer having a high coefficient of friction inner surface and an outer layer of a highly slippable material. An outer layer covers the inner layer and comprises an inner surface also of a highly slippable material; the outer surface of the outer layer may comprise a layer of a conventional condom. As a result, the highly slippable interface is formed between the two layers of the condom. The high coefficient of friction of the inner layer slides over the erect penis and provides a secure means of holding it in place, thereby eliminating the need for the
tight rim portion of conventional condoms. Not only does this double layer design enhance protection (by providing two layers, instead of one) but it may also aid in minimizing premature ejaculation due to the reduced friction.
Figs. 17-18 provide an example of the application of the SSS rule in other non-bandage applications. For example, as shown inFig. 17, a stack of heavyplates 400 (e.g., such as those used for temporarily covering potholes or other openings in a roadway) are being transported by a flatbed 402. If a first set of plates 404 is to be delivered to a first location, a second set of plates 406 is to be delivered to a second location and a third set of plates 408 is to be delivered to a third location, it is very desirable to insert a highly slippage, low friction interface between these different sets of plates. In particular, as the stack of plates 400 is loaded onto the flatbed 402, a first highly slippable low friction interface is formed between two highly slippable, low friction layers 410 A and 410B that are positioned between the second 406 and third 408 sets of plates. Each of these layers comprise an underside (not shown) that can be releasably or fixedly secured to the respective faces of the two adjacent plates. In contrast, the facing sides of these two layers 410A/410B are highly slippable, low friction material. Similarly, another highly slippable , low friction interface is formed between two highly slippable, low friction layers 412A and 412B that are positioned between the first 404 and second 406 sets of plates. Again, each of these layers comprise an underside (not shown) that can be releasably or fixedly secured to the respective faces of the two adjacent plates. In contrast, the facing sides of these two layers 412A/412B are highly slippable, low friction material. As a result, sliding will only occur at these interfaces and will not occur where any two plates are in direct contact with each other. Because of this "controlled-site slippage", it is necessary to immobilize the overall stack of plates 400 during transport using releasable securement means 414 (e.g., ratchet 416 and screw 418) that prevents any sliding motion of the stack of plates 400 during transport. Once the flatbed 402 arrives at the first location, the securement means 414 is disengaged (e.g., loosening the ratchet 416 on the screw 418) and the first stack 404 of plates can be slid off the overall stack 400 with slippage only occurring at the 412A/412B layer interface, i.e., there is no slippage of plates at interfaces 418, 420, etc. Once the first set of plates 404 is delivered, the securement means 414 is re-engaged with the two remaining stacks 406 and 408 for transport to the second location. Once at the second location, the securement means 414 is disengaged and the second stack of plates 406 is slid off of the overall stack 400 with slippage only occurring
at the 410A/410B layer interface, i.e., there is no slippage of plates at interfaces 422, 424, etc. The sequence is repeated with regard to the third location. It should be noted that in order to properly secure the plates from the start, it is necessary to load the bottom-most plate of the overall stack 400 on a spacer 426 so that the lower clamp 428 can grip the bottom-most plate. The key feature is that selected slippage is being implemented. Fig. 18 provides an alternative releasable securement means 414' that uses the screw 418 (or pole) and end nuts 430A and 430B for releasably securing the screw 418 through aligned holes (not shown) in the plates 400. The releasable securement means 414' also immobilizes the stack 400 during transport but otherwise, use of the selected slippage is similar to that discussed for Fig. 17.
The subj ect matter of U. S . application Serial No .09/615 ,211 , filed on July 13 , 2000, and U.S. application Serial No. 60/349,587, filed on January 18, 2002, are related to the inventions disclosed herein and both are incorporated by reference herein.
Without further elaboration, the foregoing will so fully illustrate my invention that others may, by applying current or future knowledge, readily adapt the same for use under various conditions of service.