WO1993010727A1

WO1993010727A1 - Vascular support sleeve

Info

Publication number: WO1993010727A1
Application number: PCT/US1992/002452
Authority: WO
Inventors: Edward J. Arkans
Original assignee: Aci Medical, Inc.
Priority date: 1991-11-25
Filing date: 1992-03-24
Publication date: 1993-06-10
Also published as: AU2256892A

Abstract

A device for providing uniform circumferential tension and graduated compression to a swollen or bloated limb has two limb-enclosing panels (10, 16) which may be releasably engaged to substantially encircle the limb. In one embodiment, the limb-enclosing panels are engaged along a first pair of edges (12, 18) by a lace or drawstring (26) which can be tightened or loosened to provide a continuous range over which the limb may be compressed and to equalize the circumferential tension over the length of the device. The limb-enclosing panels are then engaged along a second pair of edges (14, 20) by a slide fastener (54) or other suitable connector which allows the device to be easily applied and removed. Whereas the first limb-enclosing panel (10) may be of a predetermined shape and size, the second limb-enclosing panel (16) is tailored according to the contour and size of the limb so that when joined with the first limb-enclosing panel (10), the two limb-enclosing panels (10, 16) fittingly encircle the afflicted limb.

Description

VASCULAR SUPPORT SLEEVE

BACKGROUND OF THE INVENTION

The present invention relates generally to a medical support device and, more particularly, to an adjustable support sleeve providing uniform circumferential tension and graduated pressure for therapeutic purposes.

People and animals have long suffered from disorders of the vascular system. Diseases of the veins and lymph vessels, such as post phlebitic limb, varicose veins and lympheda, as well as obesity and aging, can cause limbs to swell, discolor and ulcerate. The application of inward pressure about limbs to treat such diseased limbs is not novel. In fact, treatments using wrappings date back to the earliest recorded descriptions of these diseases.

The amount of pressure necessary for successful treatment is critical. While too little pressure results in insufficient improvement in the limb's condition, too much pressure can aggravate a patient's condition causing additional swelling, and in extreme cases, paralysis and gangrene. It is, therefore, essential that a device be adjustable to provide a wide range of pressure levels with a graduated profile, that is, increase in pressure as distance along the limb from the patient's heart

-increases, and be capable of maintaining precise pressure profiles when necessary. As lymphedema resolves, the limb becomes less swollen yet the underlying venous disease may still be present to cause swelling at a later time. It is, therefore, necessary that a support device be readily adjustable to accommodate dramatic increases or decreases in size or contour of the limb.

Elastic stockings are a common means of applying pressure to limbs. Such stockings are disclosed in British Pat. No. 10,439 to Burgum and U.S. Pat. No. 3,605,122 to Myers. Due to nature of elastic materials, these devices neither provide sufficient compressive force nor are capable of maintaining precise levels of graduated pressure. Support devices using inelastic material or material highly resistant to stretching are also known. Leather stockings were used as far back as the late 1600's for the treatment of swollen limbs. More modern support devices are disclosed in U.S. Pat. No. 3,845,769 and U.S. Pat. No. 4,215,687, both issued to Shaw. These devices cannot be removed and reapplied without altering circumferential tension or the pressure applied thereby. Other support devices use a combination of elastic and inelastic materials. Such a device is disclosed in U.S. Pat. No. 2,696,208 to Falls. It is designed solely to distribute traction forces along the length of a limb, and is incapable of providing sufficient circumferential tension as well as sufficient graduated pressure for vascular use. This device is also not suited for mobile or ambulatory patients.

Therefore, it is desirable to provide a simple and cost-effective vascular support device which applies sufficient uniform circumferential tension and graduated pressure along a limb, yet readily accommodates fluctuations in limb contour and size. SUMMARY OF THE INVENTION The present invention relates to a simple and inexpensive sleeve for controlling and maintaining uniform circumferential tension and graduated pressure about a limb for therapeutic purposes. The present invention may be placed on any limb that is swollen, discolored and/or ulcerated, and can be adjusted easily over a wide range to vary amount by which the limb is compressed.

In a preferred embodiment, the application and removal of the present invention is accomplished through a slide fastener and two elongated interfitting members. Adjustment is made through a continuous tensile force- transmitting member which when tightened compresses the encircled limb. Because the means by which the invention is applied and removed are separate and remote from the adjustment means, the invention is removed and reapplied without unintentionally varying amount of pressure on the limb. Advantageously, once the present invention is adjusted, it is capable of maintaining the adjustment through repeated application and removal.

The present invention is much easier to adapt to limbs of different size than are devices of the prior art. Simplicity and cost-effectiveness are achieved, in part, by using two limb-enclosing panels with one of the panels being of simple rectangular shape and substantially uniform size. Measurements and tailoring efforts are thus necessary only for the second panel, which is shaped and sized so that the completed sleeve will properly fit and compress the afflicted limb. The present invention is particularly well suited for ambulatory use. Since internal hydrostatic pressure in a limb is greatest during physical activity, the present invention advantageously applies sufficient compression to counteract increases in the internal hydrostatic pressure, thereby resisting further swelling of the limb.

As compression at a point along the length of a limb is directly proportional to circumferential tension and inversely proportional to the effective diameter of the limb at that point, the compressive forces progressively increase as limb diameter decreases from the calf to the ankle area. The result is a graduated pressure profile which counteracts the limb's internal hydrostatic pressure.

When the limb's diameter substantially increases or decreases, as with lymphedema, the present invention is readjusted manually by loosening or tightening the tensile force-transmitting member to reapply the proper amount of compression. The present invention is also adjustable manually to accommodate bandages or the like which may ^• further increase the diameter of the limb.

When the limb changes dramatically in size so that proper fit and therapeutic compression can no longer be obtained by loosening or tightening the tensile force- transmitting member, the second limb-enclosing panel can be replaced by a larger or smaller second panel so that the sleeve properly fits the limb.

Because the sleeve of the present invention conforms closely to the shape of the limb and is of a flexible, nonstretchable construction, it need not be removed in order for limb volume to be accurately measured. Furthermore, it can be made free of metal parts, enabling procedures such as x-rays or magnetic resonance imaging to be performed without removal.

Accordingly, the present invention comprises a first limb-enclosing panel of substantially nonstretching construction extendable partially around a limb in a circumferential direction and having first and second opposed edges, a - second limb-enclosing panel of substantially nonstretching construction extendable partially around a limb in the circumferential direction and having first and second opposed edges, the second limb-enclosing panel being combinable with the first li b- enclosing panel to encompass the limb, means for adjustably joining the first edge of the first limb enclosing panel to the first edge of the second limb- enclosing panel for adjusting circumferential compression at which the support sleeve engages the limb, and means of releasably joining the second edge of the first limb enclosing panel to the second edge of the second limb- enclosing panel in a predetermined spatial relationship.

Additional objects and features of the invention will become apparent from the following detailed description, taken together with the accompanying drawings showing preferred embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention may be more fully understood from the following detailed description, together with the accompanying drawings, wherein similar reference characters refer to similar elements through and in which:

FIGURE 1 is a top-plan view of a vascular support sleeve which has a lace, a zipper and a lining constructed according to a preferred embodiment of the present invention;

FIGURE 2 is a perspective view of a continuous tensile force-transmitting member wound about a cylinder; FIGURE 2A is a horizontal cross-sectional view of the cylinder of FIGURE 2 taken in the direction 2A;

FIGURE 3 is a perspective view of the vascular support sleeve of FIGURE 1 on a leg with the lace and zipper engaged to show their diametrically-opposed positions; FIGURE 4 is a side-elevational view of the vascular support sleeve of FIGURE 1 on a leg, including a portion of a bed on which the leg rests; and

FIGURE 5 is a top-plan view of the vascular support sleeve of FIGURE 4.

FIGURE 6 is a perspective view of a second panel of the vascular support sleeve.

FIGURE 7 is a perspective view of the vascular support sleeve of FIGURE 1 with means for adjustably joining the limb-enclosing panels partially disengaged for clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGURES 1 and 3, a first limb- enclosing panel 10 constructed in accordance with a preferred embodiment of the present invention has a irst edge 12 and a second edge 14. A second limb-enclosing panel 16 has a first edge 18 and a second edge 20. The panels 10 and 16 are joined along their first edges 12 and 18, and along their second edges 14 and 20, to form a vascular support sleeve 21 which extends circumferentially about a patient's limb to support the vascular structure therein. The first edges 12 and 18 are joined in a manner permitting adjustment as well as uniform distribution of circumferential tensile force about the limb. The second edges 14 and 20 are joined in a manner permitting subsequent removal and reapplication of the present invention without altering compression about the limb.

The first edges 12 and 18 are each equipped with rows of eyelets 22 to facilitate the adjustable joining of the panels 10 and 16 by a tensile force-transmitting member 26 which engages the eyelets. The eyelets 22 are positioned proximate to each other, and the tensile force- transmitting member 26 being of continuous and substantially inelastic construction, applies a substantially uniform tensile force over the sleeve 21 causing the circumferential tension about the limb to be equal at all points along length of the sleeve 21. This equalizing effect occurs to a large extent as the edges 12 and 18 are initially fastened together. Any remaining nonuniformities are subsequently eliminated as the patient moves.

The tensile force-transmitting member 26 is preferably a lace or drawstring loomed alternately through the eyelets 22, as shown in FIGURE 1, so that free ends 28 thereof can be readily fastened together or otherwise interlocked. The member 26 is tightened as it is laced to apply a predetermined amount of circumferential tensile force, or tension, about the patient's limb. A fastening device 30, such as that disclosed in U.S. Pat. No. 3,564,670, may be used to adjustably fasten the ends 28 thereby maintaining the preselected circumferential tension.

Referring now specifically to FIGURE 2, a substantially inelastic, continuous tensile force- transmitting member 34 wound tightly about a cylinder 36 is illustrated to demonstrate the forces at work in the vascular support sleeve of the present invention. The relationship between the tensile force, or tension, (F) on the member 34, the diameter (D) of the cylinder 36, and bearing stress (P) per unit area, borne by the cylinder as a result of the tensile force (F) is:

P = 2F dD where (d) is the unit length of the cylinder 36 found by dividing length (L) of the cylinder 36 extending between top and bottom windings of the member 34, by the distance (1) between two adjacent windings of the member 34.

As the relationship above shows, the bearing stress (P) per unit area is directly proportional to the tensile force (F) , and inversely proportional to the diameter (D) of the cylinder 36. Applying this relationship to the present invention, the compression per unit area applied to the limb by the sleeve 21 is represented by (P) . The tensile force exerted by the tensile force-transmitting member 26, and in turn, by the sleeve 21, is represented by (F) , (D) is the diameter of the limb, and (d) substantially equals total length 38 of the sleeve divided by distance 40 between each of the eyelets 22.

Since the tensile force (F) is substantially uniform throughout the sleeve 21, as the diameter (D) of the limb varies along length of the limb, the compression (P) per unit area applied by the sleeve 21 similarly varies, though it varies inversely to the diameter (D) . Specifically, as the diameter (D) increases, the compression (P) per unit area decreases, and vice versa. As shown in FIGURE 3, the sleeve 21 encircling a lower leg portion provides uniform tension through the tensile-force transmitting member 26, but because diameter 42 at ankle 44 is less than diameter 46 at calf 48, the compression (P) per unit area at the ankle 44 is greater than the compression (P) per unit area at the calf 48. Along the limb between the ankle 44 and the calf 48, the compression P per unit area is graduated as it varies continuously due to change in the diameter D of the limb between the ankle 44 and the calf 48.

The second edges 14 and 20 are equipped with complementary elongated interfitting members 50 and 52, respectively. A slide fastener 54 is attached to one of the interfitting members so that it can readily engage and disengage the interfitting members 50 and 52 to releasably join the second opposed edges 14 and 20.

In the preferred embodiment, the interfitting members 50 and 52 and the slide fastener 54 comprise a conventional zipper or zipper-type assembly capable of being engaged or disengaged with a single longitudinal motion. Such assemblies include fasteners where one interfitting member has a protruding longitudinal ridge and the other interfitting member has a receding longitudinal ridge capable of receiving the protruding longitudinal ridge to releasably join the two edges. The ridges of such assemblies are also engaged and disengaged by a longitudinal movement of a slide fastener similar to those of conventional zippers.

Although the limb-enclosing panels may be of any shape, it is preferred that the first edges, 12 and 18, and the second edge 14, be substantially straight, with the remaining the second edge 20 of the second limb- enclosing panel 16 being substantially curved. While the substantially straight edges 12, 18 and 14 contribute to

^• the simplicity of the sleeve, the curved edge 20 allows the invention to fittingly encircle the limb upon engagement. One or more darts 56 may also be provided in the second limb-enclosing panel to allow the invention to better match contour of the limb.

To avoid the problems posed by elastic support devices, the limb enclosing panels 10 and 16 are made from substantially nonstretching material having at least one direction of weave or "grain" 58, along which the material has a high modulus of elasticity. The direction of the grain 58 is such that it is substantially normal to the first edges 12 and 18 and runs circumferentially about the limb. Being substantially inelastic, the panels 10 and 16 when properly engaged effectively provide a graduated compression profile to counteract hydrostatic pressure exerted by blood and fluids in the limb which cause swelling, discoloration or ulceration.

A lining member 60 may be provided at sides of the limb-enclosing panels which engage the limb. The lining member 60 is preferably absorbent, comfortable and smooth to the touch. Cotton flannel, for example, is well suited for this purpose. The lining member 60 also preferably extends a preselected distance beyond one of the first edges 12 and 18 and one of the second edges 14 and 20 to act as protective flaps 62 preventing the tensile force-transmitting member 26 and the slide fastener 54 from causing injury or discomfort to the limb. In the illustrated embodiment, the protective flaps 62 extend from both the first edge 14 and the second edge 12 of the first limb-enclosing panel 10.

Referring now to FIGURE 3, the adjustable joining means, which in this embodiment is the continuous tensile force-transmitting member 26, and the releasable joining means, which in this embodiment is the slide fastener 54 engaging complementary elongated interfitting members 50 and 52, are positioned such that they substantially diametrically oppose each other when the limb-enclosing panels 10 and 16 are joined in the manner illustrated. This position allows the ambulatory user to readily apply and remove the present invention using the slide fastener 54 without disturbing the tensile orce-transmitting member 26. Once the tensile force-transmitting member 26 is adjusted, the sleeve 21 provides a predetermined profile of compressive forces and is easily removed and reapplied without altering that profile.

Referring now to FIGURES 4 and 5, the application of the vascular support sleeve 21 is accomplished by encircling the limb with the first and second panels 10 and 16 which have been joined at their second edges 14 and 20 by the slide fastener 54 and the elongated interfitting members 50 and 52. The sleeve 21 is adjusted about the limb while the patient is supine or otherwise in a prone position whereby the internal hydrostatic pressure of the limb, and thus its diameter (D) , is at a minimum. Upon being laced through the eyelets 22 of the first and second panels 10 and 16, the tensile force-transmitting member 26 is tightened so that the first edges 12 and 18 are brought together, and the sleeve 21 compresses the limb. Once the proper level profile of compressive forces is achieved, the tensile force-transmitting member 26 is secured by the fastening device 30 to maintain the predetermined level of compression.

Therapeutic compression is achieved when the sleeve 21 substantially counteracts any increase in the limb's internal hydrostatic pressure and/or the diameter (D) . Advantageously, the inelasticity of the panels 10 and 16 ensures that therapeutic compression is maintained once it is achieved. It is important that the tensile force- transmitting member 26 be adjusted and fastened in manner whereby the tensile force exerted thereby is evenly distributed throughout the sleeve 21. The eyelets 22 allow the tensile force-transmitting member 26 to substantially redistributes minor excess tensile force caused by uneven or improper lacing. The eyelets 22 allow the tensile force-transmitting member 26 to move substantially without friction between the first edges 12 and 14 in order to readjust itself. Movement of the limb further facilitates such minor readjustment.

Referring now to FIGURES 6 and 7, when the limb experiences a dramatic change in shape or size so that the proper compression cannot be achieved by manual adjustment of the tensile force-transmitting member 26, the second panel 16 is replaced by a new second panel 68 which may be either smaller or larger than the replaced panel 16. To do so, the tensile force-transmitting member 26 is unlaced from the eyelets 22 of the first and second panels 10 and 16, and relaced through the eyelets 22 of the first and new panels 10 and 68. The sleeve 21 is again adjusted through the tensile force-transmitting member 26 to properly fit and apply therapeutic compression to the limb.

The appended claims are not limited to the embodiments described herein but rather are intended to cover all variations and adaptions falling within the true scope and spirit of the present invention. For example, the vascular support sleeve disclosed and claimed herein is not limited to use on a leg but is useful for therapeutic compression of an arm, as well. Furthermore, it is not limited to use on human limbs, but can be also used on the limbs of animals. The sleeve of the invention is therefore applicable broadly to appendages of all types which may require compression as a means of treating swelling or bloating. The means of releasably joining the limb-enclosing panels are also not limited to variations of the conventional zipper but encompass any means whereby a predetermined spatial relationship between two members can be easily released and reattained.

Claims

What is claimed is:

1. A vascular support sleeve for a limb comprising: a first panel of substantially nonstretching construction extendable partially around a limb in a circumferential direction and having first and second opposed edges; a second panel of substantially nonstretching construction extendable partially around a limb in said circumferential direction and having first and second opposed edges, the second panel being combinable with the first panel to encompass and compress the limb; means for adjustably joining the first edge of the first panel to the first edge of the second panel to control circumferential compression of the limb by the support sleeve; and means for releasably joining the second edge of the first panel to the second edge of the second panel in a predetermined spatial relationship.

2. The vascular support sleeve of claim 1 wherein: the first and second panels comprise a flexible fabric.

3. The vascular support sleeve of claim 1 wherein: the first and second edges of said panels extend substantially lengthwise along the limb when the support sleeve encompasses the limb.

4. The vascular support sleeve of claim 1 wherein: said adjustable joining means comprises a tensile force-transmitting member.

SUBSTITUTE SHEET

5. The vascular support sleeve of claim 4 wherein: the first edges of said two panels have eyelets; and the tensile force-transmitting member is inserted through the eyelets to join the panels.

6. The vascular support sleeve of claim 1 wherein: said releasable joining means comprises complementary elongated interfittingmembers extending along the second edges of said panels; and a slide fastener for engaging and disengaging said elongated interfitting members.

7. The vascular support sleeve of claim 6 wherein: said complementary elongated interfittingmembers comprise interlocking links.

8. The vascular support sleeve claim 1 wherein: said first and second panels comprise fabric having at least one grain that is substantially resistant to stretching.

9. The vascular support sleeve of claim 8 wherein: said grain substantially resistant to stretching is substantially normal to the first edges of the said panels.

10. The vascular support sleeve of claim 1 wherein: said first and second edges of the first panel and said first edge of the second panel are substantially straight; and said second edge of the second panel is curved to provide the support sleeve with a contour substantially conforming to the limb when said

SUB_ST_I UTE _SHEET adjustable joining means and said releasable joining means are engaged.

11. The vascular support sleeve of claim 10 wherein: said second panel has at least one dart to further define the contour of the support sleeve.

12. The vascular support sleeve of claim 1 which further comprises: a lining member attached to each of said panels.

13. The vascular support sleeve of claim 12 wherein: said lining members extend beyond at least one of said first edges and at least one of said second edges.

14. The vascular support sleeve of claim 12 wherein: said lining members comprise substantially absorbent fabric layers comfortable to the limb.

15. The vascular support sleeve of claim 1 wherein: said adjustable joining means comprise a fastener capable of withstanding tensile forces exerted between the first edges of the two panels.

16. The vascular support sleeve of claim 1 wherein: said adjustable joining means are substantially diametrically opposed to said releasable joining means when the first and second edges of said panels are joined.

17. A vascular support sleeve for a limb comprising: a first panel of substantially nonstretching construction extendable partially around a limb in a

SUBSTITUTE SHEET circumferential direction and having first and second opposed edges; a plurality of second panels of varying shapes and sizes, each of substantially nonstretching construction extendable partially around a limb in said circumferential direction and having first and second opposed edges, each of said second panels being combinable with the first panel to encompass and compress the limb; means for adjustably joining the first edge of the first panel to the first edges of the second panels to control circumferential compression of the limb by the support sleeve; and means for releasably joining the second edge of the first panel to the second edges of the second panels in a predetermined spatial relationship.

18. The vascular support sleeve of claim 17 wherein: said first and second edges of the first panel and said first edges of the second panels are substantially straight; and said second edges of the second panels are curved to provide the support sleeve with a contour substantially conforming to the limb when said adjustable joining means and said releasable joining means are engaged.

19. The vascular support sleeve of claim 17 wherein: said vascular support sleeve comprises of one of said first panel and one of said second panel, which when joined with said first panel by said adjustable means and said releasable means substantially encompasses and compresses the limb.

_SUB_ST_ITUTE_SHEET