Abstract:
A protective and pressure normalizing device including a support member having an exterior wall and an interior wall which define a first chamber and a second chamber, and a pressure adjustment device sealed within at least a portion of the second chamber, the pressure adjustment device defining a third chamber and a medium transfer passageway interconnecting the first chamber and third chamber.

Description:
[0001]    The present invention claims the benefit of U.S. Provisional Patent Application Serial No. 60/305,237, filed Jul. 13, 2001, which is hereby incorporated by reference in its entirety. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention generally relates to devices and methods for stabilizing and supporting a structure, especially a body part of a user. The invention, more specifically, is an inflatable device that provides protection for, and relieves pressure on the body part, especially when the body is in a supine or semi-Fowler&#39;s position  
         BACKGROUND OF THE INVENTION  
         [0003]    Devices for supporting a body extremity have been developed. For example, U.S. Pat. No. 5,489,259 to Jacobs et al. (“Jacobs”) relates to a pressure-normalizing single-chambered static pressure device for supporting and protecting a body extremity, in particular a heel. That device has an inflatable member with exterior and interior surfaces, a plurality of seams to connect the exterior and interior surfaces together along a line corresponding to the Achilles&#39; tendon and the ankle bones, a plurality of apertures along those seams, and a nozzle.  
           [0004]    In order to inflate the Jacobs&#39; device, an external pump is attached to the nozzle and the device is inflated to a predetermined pressure by a third party or the patient, then the device is left alone and is said to conform to the extremity.  
           [0005]    A problem with devices, such as those described in Jacobs, is that the device may be over-inflated or even under-inflated. Such results may become deleterious to the patient. In addition, when the devices are inflated with air, there is a significant risk of cross-contamination caused by different individuals orally adjusting the pressure of the medium through the nozzle. Moreover, an external device, such as a pump, is required to adjust the pressure of the medium within the device, even after the device is initially inflated to a desired level, to make modifications for climatic conditions, changes in elevation, or leakage.  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention relates to a protective and pressure normalizing device. The device includes a support member having an exterior wall and an interior wall which define a first chamber and a second chamber, and a pressure adjustment device sealed within at least a portion of the second chamber, the pressure adjustment device defining a third chamber and a medium transfer passageway interconnecting the first chamber and third chamber.  
           [0007]    The present invention also relates to a protective and pressure normalizing device for a body extremity. The device includes a support member having an exterior wall and an interior wall which define a first chamber, a second chamber, and a joint aperture. A manually actuated pump is sealed within at least a portion of the second chamber. The manually actuated pump includes a resilient member encapsulated within an envelope, wherein a portion of the envelope forms a one-way check valve in communication with the first chamber.  
           [0008]    Another aspect of the present invention relates to a method for protecting and normalizing the pressure on a structure. The method involves providing a support member having an exterior wall and an interior wall which define a first chamber and a second chamber, and a pressure adjustment device sealed within at least a portion of the second chamber, the pressure adjustment device defining a third chamber and a medium transfer passageway interconnecting the first chamber and third chamber. The structure is positioned in the support member.  
           [0009]    In the device and method of the present invention, the pressure of a medium within the device is adjusted through an integrated pressure adjustment device. As used herein, an integrated pressure adjustment device is located and sealed within the chamber or bladder being inflated. As further used herein, a pressure adjustment device is sealed within a chamber when it is in communication for the transfer of medium to the chamber whose pressure it is being used to adjust and is not in constant communication with a medium source external to the chamber. By sealing the pressure adjustment device within the chamber being inflated, thereby controlling and restricting the flow of medium to any location other than the chamber being inflated, the pressure adjustment device is unable to leak to the outside of the support member. Accordingly, the device more efficiently maintains its pressure. Further, the need for multiple components, such as the support device in combination with external pressure adjustment devices to adjust the pressure of the medium is eliminated. Thus, pressure of the medium within the chamber can be easily adjusted on-site by the user without the need for obtaining an external pressure adjustment device.  
           [0010]    The device of the present invention, in a specific embodiment, is an inflatable device that provides protection for, and relieves pressure on the heel area of the foot, when the body is in a supine or semi-Fowler&#39;s position. When used to stabilize a foot, the device and method of the present invention can be used in order to prevent shortening of the Achilles tendon, i.e., “foot drop.” The device is adaptable to fit different sized body parts and can be worn on either a left or right extremity of the user. In addition, the device of the present invention minimizes pressure contact between the body part and any surface on which it is placed, for example, a hospital bed, thereby, decreasing the risk of the formation of decubitus ulcers on the body part as a result of such contact (while keeping the device lightweight). Moreover, the device of the present invention limits contact between the body part of a user, especially the toe area of the foot, and objects in the user&#39;s surroundings such as sheets, blankets, etc. Further, when used for the foot, the device separates the ankles, preventing them from crossing and thereby reducing additional pressure when the hips are rotated. In addition, the device allows for air circulation and provides protection for the sides and bottom of the foot or any other body part positioned in the device.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a perspective, partially cutaway view of a first embodiment of the device of the present invention including a pressure adjustment device;  
         [0012]    [0012]FIG. 2 is a top view of the pressure adjustment device of FIG. 1;  
         [0013]    [0013]FIG. 3 is a partial, cross-sectional view of the device of FIG. 1 taken along the lines  3 - 3 ;  
         [0014]    [0014]FIG. 4 is a perspective view of FIG. 1 showing edges  72  and  74  which are joined to form the device of FIG. 1;  
         [0015]    [0015]FIG. 5 is a cross-sectional view of FIG. 4 taken along the lines  5 - 5 ;  
         [0016]    [0016]FIG. 6 is an another embodiment of FIG. 5;  
         [0017]    [0017]FIG. 7 is an another embodiment of FIG. 5;  
         [0018]    [0018]FIG. 8 is an another embodiment of FIG. 5; and  
         [0019]    [0019]FIG. 9 is a side perspective view of an alternative embodiment of FIG. 1. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]    Referring to FIGS.  1 - 4 , the present invention relates to a device  10  including a support member  12  which includes an integrated pressure adjustment device  14  within the support member  12 . In particular, the support member has an exterior wall  16  and an interior wall  18  which define a first chamber  20 , shown in FIGS. 3 and 5- 8 . The pressure adjustment device  14  is located within the chamber  20  whose pressure it is adjusting and can be located at any position within the chamber. The support member  12  can be used to stabilize a body part (e.g., a body extremity) or any other structure. When used to stabilize a foot, the device and method of the present invention can be used in order to prevent shortening of the Achilles tendon, i.e., “foot drop.” In addition, the device of the present invention minimizes pressure contact between the body part and any surface on which it is placed as well as other objects in the user&#39;s surrounding, thereby decreasing the risk of the formation of decubitus ulcers on the body part as a result of such contact.  
         [0021]    [0021]FIG. 1 shows a perspective view of a device  10  according to the present invention. Device  10  includes a support member  12  which has an exterior wall  16  and an interior wall  18  which define a first chamber  20 , shown in FIGS. 3 and 5- 8 . The support member  12  also includes a plurality of non-support regions  22 , one or more securing devices  24 , and an aperture for a joint of a user  26 . In addition, the support member  12  includes a pressure adjustment device  14 .  
         [0022]    Referring back to FIG. 1, in this embodiment, the pressure adjustment device  14  is positioned and sealed within the first chamber  20  at a first end  28  adjacent a top edge of the support member  12 . However, the pressure adjustment device  14  may be any suitable size or shape and may be positioned at any location within the first chamber  20 .  
         [0023]    As shown in FIGS.  1 - 3 , in this particular embodiment, the pressure adjustment device  14  is a manually actuated pump which can be used to adjust the pressure of a medium in the first chamber  20 . The pressure adjustment device  14  is sealed and encapsulated within the first chamber  20  by sealing the exterior wall  16  to the interior wall  18  around the pressure adjustment device  14  by heat-sealing, radio-frequency sealing, or any other suitable technique, thereby forming a second chamber or subchamber  20   a . The second chamber  20   a  includes an inlet opening  30  which provides access to a source of a medium, such as air, used to fill chambers  20  and  20   a , but which is closed with plug  32  except when medium is to be added to the chambers  20 ,  20   a.    
         [0024]    More specifically, as shown in FIGS.  2 - 3 , the pump includes a piece of foam  34  encapsulated in an envelope formed by a first sheet  36  and a second sheet  38  positioned in the second chamber  20   a . Although two sheets  36  and  38  are shown, the foam  34  may be encapsulated in a single sheet. The envelope formed by first and second sheets  36 ,  38  defines a third chamber  20   b  within second chamber  20   a . The foam  34  is an open-cell, resiliently flexible material, such as polyurethane foam. However, any resilient member may be used, such as springs and plastic molded parts. In this embodiment, the first and second sheets  36 ,  38  are plastic sheets which are from about 0.005 inches to about 0.020 inches in thickness. However, the first and second sheets  36 ,  38  may be made of any material in any desired thickness and may be the same material or a different material than the exterior wall  16  and interior wall  18 . The first sheet  36  and second sheet  38  form a “duck-bill” type check valve  40  at seal  42 . Such valves are known in the art and are described, for example, in U.S. Pat. No. 5,144,708, which is hereby incorporated by reference in its entirety. Briefly, the first sheet  36  and second sheet  38  are adhered at seal  42  to the exterior wall  16  and interior wall  18  of the support member  12 . A barrier material  44  is disposed on the inner surface of one or both of the first and second sheets  36 ,  38  through the seal  42  to prevent fusing together of the first and second sheets  36 ,  38  at that area of the seal  42 . The barrier material  44  defines a central channel through the seal  42  which allows one-way fluid flow from the third chamber  20   b  to the first chamber  20 .  
         [0025]    Referring to FIG. 3, in this particular embodiment, the pump also includes a non-adhesive layer  46  adjacent the first sheet  36 , although the non-adhesive layer  46  may also be adjacent the second sheet  38 . The non-adhesive layer  46  prevents the first sheet  36  and/or the second sheet  38  from adhering to inner surfaces of the exterior wall  16  and interior wall  18 , and may be any suitable material, such as synthetic woven material or synthetic non-woven material. However, adhesion to the inner surfaces of the exterior wall  16  and interior wall  18  may be prevented by treating either the inner surfaces of the exterior wall  18  and interior wall  18  and/or the outer surfaces of the first and second sheets  36 ,  38  to make them non-adhesive. For example, the inner surfaces of the exterior wall  18  and interior wall  18  and/or the outer surfaces of the first and second sheets  36 ,  38  may be coated with a non-adhesive material, such as printers ink, thereby eliminating the need for a non-adhesive layer  46  in the pressure adjustment device  14 .  
         [0026]    In addition, in this embodiment, the pressure adjustment device  14  includes an intake  48  for drawing a medium, such as air, into the pressure adjustment device  14  and into the chambers  20   a  and  20   b , and, ultimately,  20 . Referring to FIG. 1, the support member  12  may also include a release valve  49  for releasing medium from first chamber  20 .  
         [0027]    Although a foam-based, manually actuated pump has been described, the pressure adjustment device  14  may be any suitable device. Other suitable pressure adjustment devices  14  include, but are not limited to, squeeze-ball type pumps, bellows, tire pumps, or electronic pumps.  
         [0028]    As shown in FIG. 1, the support member  12  forms a single first chamber  20 . However, the first chamber  20  of the support member  12  may include a series of interconnected cells that exchange the medium and redistribute weight of the structure placed within the device.  
         [0029]    The support member  12  with non-support regions  22  has an exterior wall  16  and an interior wall  18 . The exterior and interior walls  16 ,  18  can be constructed of the same or different materials.  
         [0030]    The interior wall  18  is constructed of a lightweight cotton, gauze, paper, or synthetic material which may be woven or non-woven, or any other material that is breathable and suitable for use in a hospital, alternative care, or home care environment, when the device is used to support a body part. The interior wall  18  is strong enough to secure a body part of a user and capable of being comfortably placed in contact with the body part of a user. In use, at least a portion of the interior wall  18  of the support member  12  contacts at least a portion the body part of the user.  
         [0031]    The exterior wall  16  can be constructed of any type of material so long as it meets some minimal characteristics. These minimal characteristics, which apply to both materials  16  and  18 , when the device is used to support a body part, include not applying excessive shear force to a user&#39;s tissue, providing adequate wicking characteristics so that moisture is drawn away from the skin of the body part to keep the body part at a normal temperature, and providing sufficient flexibility and pliability to conform readily to the shape of the user&#39;s body part. The exterior wall  16  and interior wall  18  may be constructed to be disposable or reusable.  
         [0032]    In an alternative embodiment, the exterior wall  16  may include an exterior reinforcing material layer and the interior wall may include an interior wicking material layer to cool and wick moisture. The exterior reinforcing material layer and interior wicking material layer may be made of the same or different materials than the exterior wall  16  and interior wall  18 . In this embodiment, at least a portion of the interior wicking material layer contacts at least a portion of the body part of the user.  
         [0033]    Referring to FIG. 1, the device  10  is divided into at least three distinct components  50 ,  52 , and  54  that correspond to a body extremity having a joint (elbow, knee, or heel/ankle) of a user. However, the device  10  may be divided into any number of components. The body extremity is divided into a posterior, anterior, and the two other sides.  
         [0034]    As shown in FIG. 1, the components are a lower portion  50 , an intermediate portion  52 , and an upper portion  54 . The interior wall  18  of the lower portion  50  contacts at least parts of the anterior and other sides of the foot (i.e., a lower region of the body extremity). The interior wall  18  of the intermediate portion  52  contacts at least a portion of the other sides of the body extremity that corresponds to the heel, which is on the posterior side of the body extremity (i.e., an intermediate region of the body extremity) and includes the joint aperture  26 . The interior wall  18  of the upper portion  54  contacts at least a portion of the posterior and other sides of the calf of the body extremity (i.e., an upper portion of the body extremity). Although the device  10  shown in FIG. 1 relates to the ankle, heel, and foot of a user, the device may be used with other body parts, e.g., a knee or an elbow, and the interior wall  18  would contact surfaces of the body part other than that described above.  
         [0035]    The joint aperture  26  exposes the joint of the body part. In this particular example, the joint is the heel. However, the joint could be any suitable joint, such as the elbow or knee. Although this particular embodiment includes a joint aperture  26 , the device could be provided without a joint aperture.  
         [0036]    To relieve pressure on the body part, the support member  12  has a plurality of non-support regions  22  interspaced throughout it. In one embodiment, shown in FIG. 4, there is a first set of non-support regions  22 ′ positioned along a line corresponding to an Achilles&#39; tendon of the calf. A second set of the nonsupport regions  22 ″ is positioned along a line corresponding to the ankle bone of the body extremity. Each of non-support regions  22 ′,  22 ″ is interspaced from the others, as shown in FIG. 4, and highlighted in FIG. 5—a cross-section of FIG. 4 taken along the lines  5 - 5 .  
         [0037]    As shown in FIG. 5, the non-support region  22  is formed by bonding predetermined portions of the interior wall  18  to the exterior wall  16  at predetermined point  56 . In some embodiments, the predetermined point  56  is a pre-selected area of the non-support region  22  wherein the remainder of the nonsupport region  22  is flat, as shown in FIG. 5, or the predetermined point  56  is the entire non-support region  22  as shown in FIG. 6 (an alternative embodiment of FIG. 5), or the predetermined point  56  is a pre-selected area of the non-support region  22  wherein the remainder of the region  22  is filled with a fluid or a predetermined piece of material  58 , as shown in FIG. 7 (an alternative embodiment of FIG. 5), or the predetermined point  56  is a pre-selected area of the non-support region  22  wherein within a predetermined portion of the remainder of the region  22  is an aperture  60 , as shown in FIG. 8 (an alternative embodiment of FIG. 5). The predetermined point  56  can be made by a heat-seal, ultrasonic sound, or other conventional means.  
         [0038]    Referring to FIGS. 3 and 5- 8 , the exterior wall  16  and interior wall  18  of the support member  12  form a first chamber  20  which includes a medium having an initial predetermined pressure. For example, the first chamber  20  of the support member  12  is filled with a medium to a pressure of about 0-50 mmHg. In one embodiment, the chamber  20  is filled with a medium to a pressure of about 0-15 mmHg. Such pressures minimize stretch of the interior and exterior walls  16 ,  18  of the support member  12  due, for example, to elevation or temperature changes. However, any desired pressure can be used. In addition, any suitable medium can be used. The medium is typically a fluid, such as gases (e.g., air) or liquids (e.g., water), suspensions, gelastic materials, as sold by EdiZone, Inc. of Utah, or any other material that reduces pressure on a body part. In this particular embodiment, the medium is air.  
         [0039]    The pressure of the air within the chamber  20  is adjusted by activating the integrated pressure adjustment device  14 . In particular, the pressure of the air is adjusted by removing the plug  32  from inlet opening  30  and manually operating the pressure adjustment device  14  to pull air into the chambers  20 ,  20   a , and  20   b  from ambient. However, when using a medium other than air, the inlet opening  30  is connected to a source of medium. By adjusting the pressure of the medium through the integrated pressure adjustment device  14 , the need for external devices to adjust the pressure of the medium is eliminated. In addition, leakage from the integrated pressure adjustment device  14  is contained within the support member  12  by closing the opening  30  with plug  32 , except when adding medium to the device  10 . This allows the pressure within the support member  12  to be easily maintained.  
         [0040]    [0040]FIG. 9 illustrates an alternative embodiment of the device of FIG. 1 without any non-support members  22 .  
         [0041]    Referring to FIGS. 1, 4, and  9 , the present invention includes a plurality of securing devices  24 . Each securing device  24  may be a support surface or a non-support surface. In either embodiment, each securing device  24  secures first and second edges  62 ,  64  of support member  12  to within a desired distance of each other and prevents device  10  from disengaging with the body part. Each securing device  24  is divided into two units, a receiver  66  and an extender  68 . In the embodiment shown in FIGS. 1 and 4, the extender  68  protrudes from edge  62 , however, the extender  68  may protrude from either edge. Receiver  66  receives the extender  68  and secures the extender  68  into a desired position. In the present embodiments, the receiver  66  is a loop device, and the extender  68  has a hook device that connects with the loop device, although any type of securing device may be used. The receiver  66  can be a single unit, as illustrated in FIG. 4, or separate units for each extender  68 , as illustrated in FIG. 9. In addition, the device may include one or a plurality of securing devices  24 . To attain maximum engagement between the edges  62  and  64 , each securing device  24  in each embodiment has a particular position such that receiver  66  receives extender  68  at a 90° angle.  
         [0042]    In another embodiment, as shown in FIGS. 1, 4, and  9 , an alternative securing device  24   a  is positioned on the lower portion  50  of the device  10 . This alternative securing device  24   a  further secures the device  10  to the body part and includes a receiver  66   a  and an extender  68   a . However, the device  10  may be provided without securing device  24   a.    
         [0043]    The device  10  illustrated in FIG. 4 is in a pre-assembled position. The device  10  is put together by joining the exterior wall  16  to the interior wall  18  at an edge  70 . Once the edge  70  is sealed, normally by heat sealing, the two particular edges,  72  and  74 , are further joined together to form the device  10 .  
         [0044]    In accordance with one embodiment of the present invention, the device  10  is pre-filled with a medium. By pre-filling the device  10 , the user is less likely to cause damage to its body part. Many individuals ignore the fact that when the temperature and/or air pressure of the environment is altered the pressure within the device  10  is also altered. Therefore, by pre-filling the device  10 , the user is unable to over inflate or under inflate the device  10 . The user can then adjust the pressure of the medium within the chamber, for example, to make up for volume changes due to climatic conditions and changes in elevation.  
         [0045]    The device  10  of the present invention can be used to stabilize a body part. For example, the support member  12  can be used for stabilizing an ankle while relieving pressure on the heel of the foot, a knee while relieving pressure on the knee of the leg, or an elbow while relieving pressure on the elbow of the arm. The knee, ankle/heel, and elbow are collectively referred to as a flexible joint or a bendable joint.  
         [0046]    In use, the user positions a body part, such as a leg, foot, or arm, in the support member  12 . If present, securing devices  24  and  24   a  are used to secure the support member  12  to the body part. The user then fills/adjusts the chamber  20  of the support member to a desired pressure using the pressure adjustment device  14 . In particular, to increase the pressure within the chamber  20 , the user removes plug  32 , positions a finger or thumb over intake  48 , and alternately depresses and releases finger pressure on the foam  34  for a sufficient number of pulsations to reach the desired pressure. The exterior and interior walls  16 ,  18  may be transparent in order to allow the user to position a finger or thumb over intake  48  or a marking may be provided on the exterior and/or interior walls  16 ,  18  to allow the user to correctly position his/her finger or thumb. The user then repositions plug  32  in opening  30  to seal the pressure adjustment device within device  10 . To decrease the pressure within the chamber  20 , the user opens a release valve  49 , if present, on the support member  12 , which allows medium within the chamber  20  to be released. Alternatively, the user may fill/adjust the chamber  20  to a desired pressure prior to securing the support member  12  to the body part.  
         [0047]    Although preferred embodiments have been depicted and described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions, and the like can be made without departing from the spirit of the invention and these are therefore considered to be within the scope of the invention as defined in the claims which follow. Further, the recited order of processing elements or sequences, or the use of numbers, letters, or other designations therefor, is not intended to limit the claimed process to any order except as may be specified in the claims.