Prosthetic liner with external fabric seal

Abstract

A prosthetic liner for use with a prosthetic socket having a thermoplastic elastomer (TPE) layer in contact with an amputee's residual limb. The TPE layer is not uniform in thickness but has a ridge extending circumferentially around the TPE layer. A fabric outer layer covers the outer surface of the TPE layer that is conformal to the ridge and serves as a substrate to form a mechanical bond with the elastomeric material. The elastomeric material is impregnated into the fabric outer by applying uncured material to the fabric outer layer and the apex surface at least within the sealing area to create an air-tight boundary layer when inserted into the socket. When a vacuum is applied, air is expelled from the volume beneath the sealing layer.

Description

[0001] Cross-references to related applications

[0002] This application is a partial continuation of application number 16 / 120,791, filed on September 4, 2018, entitled “Prosthetic Liner with External Fabric Seal,” the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to liners for prosthetic components. More specifically, this invention relates to vacuum-sealed liners having a thermoplastic elastomer layer comprising a sealing ridge, such that an airtight seal is formed when a vacuum is applied in the region between the prosthetic socket and the sealing liner. Background Technology

[0004] Currently, as seen in U.S. Patent No. 8,097,043 granted to Egilsson, suspension liners can be configured to provide a sealing device between the stump and the prosthesis socket, the disclosure of which is incorporated herein by reference. Such liners are typically made of an impermeable elastomeric material such as silicone and may include a reinforcing layer located between or outside the inner and outer surfaces of the liner body portion to provide resistance to axial elongation of the elastomeric body. This reinforcement typically does not restrict radial expansion or stretching of the liner body.

[0005] Various arrangements have been considered when constructing the suspension liner to securely hold it within the rigid prosthesis socket, as user movement typically causes the prosthesis to swing away from the user's residual limb. Among various methods, such as ambulation-pumping mechanisms that remove any residual air from the space between the liner and the prosthesis, the most effective method is to fabricate a seal around the liner. This sealed suspension liner has an elastic material attached to the braided layer, thus providing friction-inducing properties to the liner itself. When the user inserts her residual limb, using the attached suspension liner, the user effectively forces her limb into the prosthesis socket, and then the annular seal with a circumference greater than the suspension liner engages with the prosthesis.

[0006] In other applications, it may be desirable to more reliably secure the bushing within the socket by creating a low-pressure (vacuum) pressure at the distal end of the rigid socket and at the distal end of the suspension bushing inserted into the socket. While the casing liner is normally held within the socket, a low pressure can be maintained at the distal end of the rigid socket, isolating the interior of the socket at its distal end from the atmosphere. Opening the distal end of the socket to the atmosphere releases the vacuum or low pressure within the socket, allowing for easy removal of the bushing-attached remnant from the socket. The distal end of the socket, located between the distal end of the bushing and the distal end of the socket, can be evacuated using a pump or other device. Valves or other suitable devices are typically used to open and close the communication between the distal end of the socket and the surrounding atmosphere.

[0007] Other arrangements for providing a proper seal between the outside of the bushing and the inside of the hard socket are known in the prior art, the hard socket comprising an external airtight sleeve covering the interface region between the proximal end of the hard socket and the adjacent bushing body.

[0008] Therefore, one object of the present invention is to provide an improvement that overcomes the aforementioned shortcomings of prior art devices and provides an improvement that significantly contributes to the advancement of lining technology.

[0009] Another object of the present invention is to form a convenient and improved sealing arrangement between the interior of the elastic bushing and the prosthesis socket.

[0010] The foregoing outlines some of the relevant objectives of the present invention. These objectives should be interpreted merely as illustrative of some more prominent features and applications of the intended invention. Many other beneficial results can be obtained by applying the disclosed invention in different ways or by modifying the invention within the scope of this disclosure. Therefore, in addition to the scope of the invention as defined by the claims in conjunction with the accompanying drawings, other objectives and a more comprehensive understanding of the invention can be derived by referring to the detailed description of the invention and preferred embodiments. Summary of the Invention

[0011] This invention generally relates to a ridged, layered liner for prosthetic components. Specifically, the invention relates to a liner having an elastomeric layer, a fabric outer layer, and a sealing layer, wherein the elastomeric layer has multiple ridges. The fabric outer layer is bonded to the outer surface of the elastomeric layer and forms a suitable substrate for impregnating the elastomeric material therein. The sealing layer is applied to the fabric in an uncured state with a viscosity sufficient to "wet" the fabric in the applied area, so that once cured, the sealing layer forms an airtight seal between the fabric and the substrate.

[0012] Typically, sealing ridges are formed using a separate molding process different from that of the elastomeric layer. That is, the elastomeric layer does not have any sealing ridges because they are essentially embedded into the knitted or elastomeric layer via adhesive. In this case, when the sealing ridges are embedded in the elastomeric layer, they are referred to as protrusions. However, in this invention, configuring the elastomeric layer to be molded to include multiple sealing ridges provides advantages over similar techniques. The protrusions are more durable because they are protected not only by the reinforcing layer but also by an outer layer that only covers the sealing ridges. Therefore, if the outer layer is eventually removed after years of continuous use, the suspension liner will still have a slight sealing effect because the protrusions remain within the elastomeric layer.

[0013] The more relevant and important features of the invention have been outlined rather broadly above to better understand the detailed description that follows and to more fully appreciate its contribution to the prior art. Other features of the invention will be described below, forming the subject matter of the claims. It will be understood by those skilled in the art that the disclosed concepts and specific embodiments can be readily used as the basis for modifications or the design of other structures for achieving the same purpose as the invention. It should also be recognized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. Attached Figure Description

[0014] To gain a more complete understanding of this disclosure and its advantages, reference is now made to the following description in conjunction with the accompanying drawings, wherein:

[0015] Figure 1 This is a cross-sectional view of the thermoplastic elastomer layer;

[0016] Figure 2 This is a cross-sectional view of a preferred embodiment of the suspension sleeve liner.

[0017] Figures 3-11 It corresponds to Figure 2 A cross-sectional view of the suspension sleeve liner, showing an alternative embodiment with raised and recessed portions.

[0018] Figures 12-13 This is a cross-sectional view of the suspension sleeve liner, showing an alternative embodiment of the raised portion; and

[0019] Figures 14-15 It is a cross-sectional view of a suspension sleeve liner, showing an alternative embodiment of the raised portion, particularly a liner with an elastic material impregnated within the outer layer of the fabric.

[0020] In all the views of the accompanying drawings, similar reference numerals refer to similar parts. Detailed Implementation

[0021] The following description represents the best mode currently intended for carrying out the invention. This description should not be construed as limiting, but is solely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined by the claims.

[0022] Figure 1 The illustration shows a thermoplastic elastomer layer 400 of a sealing liner 100, wherein the thermoplastic elastomer layer 400 (also referred to as TPE) having an inner elastomer surface 410 and an outer elastomer surface 420 is formed within a mold with a wall thickness of 2-9 mm. The liner 100 preferably has an open proximal end 120, the perimeter and volume of which are greater than the perimeter and volume of the closed distal end 140.

[0023] Figure 2 The illustration shows a preferred embodiment of the sealing liner 100, wherein the thermoplastic elastomer layer 400 further includes at least one sealing region 430, which preferably extends outward 3-20 mm from the inner surface 410 of the thermoplastic elastomer layer 400 and includes at least one protrusion 440. If the sealing region 430 includes more than one protrusion 440, then the plurality of protrusions 440 will be accompanied by at least one recess 450. Thus, if there are two protrusions 440, then three recesses 450 will be as follows: Figure 1 The distribution is as shown. Alternatively, the sealing region 430 may begin with a raised portion 440 instead of a recessed portion 450. In this case, the distribution is as follows: raised portion 440, recessed portion 450, raised portion 440. Therefore, the recessed portion 450 does not always have to surround the distal and proximal ends of the sealing region 430.

[0024] The outer fabric 300, synonymous with the "reinforcing layer," is bonded to the outer elastomer surface 420 of the thermoplastic elastomer layer 400 and conforms to at least one sealing region 430. The outer fabric 300 advantageously forms a suitable substrate for bonding the sealing layer 200. The sealing layer 200 conforms to the shapes of both the outer fabric 300 and the thermoplastic elastomer layer 400. The sealing layer 200 is applied to the fabric in an uncured state and has a viscosity that allows it to "wet" the fabric in that area, so that once cured, it forms an airtight seal, thereby separating the fabric above the sealing layer (not shown) from the outer fabric 300 below the sealing layer 200. Thus, the application of the outer sealing layer 200 to the outer fabric 300 provides an airtight interface between the thermoplastic elastomer layer 400 and the surrounding outer area of ​​the lining 100. Preferably, the outer sealing layer 200 is applied to impregnate the reinforcing layer 300 to form a composite material.

[0025] The outer sealing layer 200 can be composed of natural rubber, silicone, polyurethane, latex, polysulfide, vinyl, polyisoprene, or styrene block copolymer gel, but rubber is preferred because it has high abrasion resistance and high tensile strength. The force required to stretch this layer is determined by multiplying the elastic modulus of the sealing material by the cross-sectional area of ​​the sealing material.

[0026] The thermoplastic elastomer layer 400 is preferably of a type compatible with long-term dynamic wearer contact. Such materials are known in the art and may include polymers and gels containing them: silicone polyurethanes; block copolymers, such as styrene block copolymer gels, of which general, non-limiting examples may include SEBS-, SEPS-, SEEPS-, SEEBS-, and other types of styrene block copolymer gels. Other non-limiting examples of styrene block copolymer gels that may be used in the lining of the present invention include so-called “controlled distribution polymers,” such as, for example, those disclosed in U.S. Patent No. 7,226,484; U.S. Patent Application Publication No. 20070238835; and U.S. Patent Application Publication No. 20050008669, the disclosures of which are incorporated herein by reference. Other potentially useful polymers may include certain so-called “crystalline” polymers, such as, for example, those disclosed in U.S. Patent Nos. 5,952,396; 6,420,475 and 6,148,830, the disclosures of which are incorporated herein by reference. The above list is non-limiting, and the list of generally acceptable polymers and gels includes those known in the art for use in the manufacture of prosthetic liners. The term "gel" is defined as a polymer mixed with a plasticizer. An example of a liner currently using such a gel is "EZ Gel". TM The lining can be commercially sourced from Alps South, LLC.

[0027] The term "sealing region" 430 may include only one protrusion 440 or may include multiple protrusions 440. If it includes multiple protrusions 440, the sealing region 430 will have each protrusion 440 continuously adjacent to any other protrusion 440. However, if multiple protrusions 440 coexist near the distal end of the tubular body portion and multiple protrusions 440 coexist near the proximal end of the tubular body portion, then there will be two sealing regions 430 with only continuous lengths in their group. That is, the sealing region 430 in the distal end will have a continuous length of material, while the sealing region 430 in the proximal end will have its own continuous length of material. The continuous length of material refers to the elastic material used to produce the durable yet flexible sealing region 430.

[0028] Figures 2-11The diagram shows that the protrusion 440 within the elastic material can have a variety of different geometries relative to the vertical axis of the invention. For example, the protrusion 440 can be square / rectangular. Figures 2-4 , Figure 6 ), parabolic ( Figure 11 ), triangle, oval, spear-shaped, parallelogram shape ( Figure 5 ), dome-shaped ( Figure 11 ), wavy ( Figure 7 and Figure 9 This refers to protrusions or those resembling a "gripping" mechanism or shape used by those skilled in the art to "grip" an object to another. For example, finger-like protrusions resembling hooks. Figure 8 and Figure 10 Similar to constructing The "hook" portion of the "hook and loop" used. Each protrusion 440 is preferably not collinear with the outer fabric layer 300, as can be seen in the relevant diagram.

[0029] Figure 12 and Figure 13 A sealing liner 100 without recesses 450 in the elastomer layer 400 is shown. Protrusions 440 protrude from the elastomer layer 400 without recesses 450 located between, in, or near the protrusions 440. This embodiment of the sealing liner 100 is useful because it is easy to manufacture and has a thinner profile. Only the reinforcing layer 200 and the outer fabric layer 300 have recesses 450 corresponding to the recesses 450 between each protrusion 440.

[0030] Figure 14 Another embodiment of the sealing liner 100 is shown, which includes an elastic material impregnated within the fabric exterior 300 along the entire length of the sealing region 430. The elastic material is at least partially penetrated into the fabric exterior 300, and preferably completely impregnated within the fabric exterior 300.

[0031] Furthermore, the elastic material is attached as a layer that separates itself from the outer fabric by 300 degrees. Figures 2-13 Compared to this, impregnating the elastic material within the fabric exterior 300 allows the resulting composite material to have more durable properties. That is, the fabric exterior 300, along with the impregnated elastomer material, has properties similar to those of positioning a reinforcing bar (“rebar”) within a concrete structure.

[0032] Figure 15 The use of the top surface 470, which has a raised portion 440, is shown. (With) Figure 14 Conversely, the elastic material is only fully impregnated on the top surface 470 of the protrusion 440 within the outer fabric 300. Figure 14This shows that the elastic material is impregnated in the outer fabric 300 along the entire length of the sealing area 430.

[0033] Furthermore, the top surface 470 is precisely the highest or farthest point from the recessed portion 450. Figure 7 In the embodiment shown, for example, the top surface 470 will be positioned relative to the "tip" of the triangular protrusion 440 and extend downward toward the recess 450. Figure 8 In this context, the top surface 470 will be the end of the finger-like protrusion. The top surface 470 can also be considered as the surface area of ​​the protruding portion 440 that contacts the bearing wall.

[0034] preparation Figure 14 and Figure 15 The illustrated implementation comprises four steps. First, a tube with an inflatable airbag is inserted into the sealing liner 100. The inflatable airbag is located near the sealing area 430. Then, vinyl tape is wrapped around the area of ​​the raised portion 440 to prevent any unwanted silicone from adhering to any area other than the top surface 470 of the raised portion 440. The boundary formed by the applied vinyl tape will define the edge of the sealing area. The airbag is then inflated using compressed air, which stretches the outer fabric 300 to allow silicone to penetrate the outer fabric 300. The tube is then placed on a rotating arm that rotates the sealing liner 100 to allow uniform coating of the top surface 470 of the raised portion 440, while simultaneously using centrifugal force to prevent silicone from dripping.

[0035] Next, the required silicone to be applied to the top surface 470 of the protrusion 440 is prepared and mixed using a calibrated scale and a clean mixing container. Although silicone is used as the sealing material in this method, any equivalent material can be used.

[0036] Third, rotate the sealing liner 100 while simultaneously applying the prepared silicone to the top surface 470 of the raised portion 440 using a brush or other applicator. The applied silicone is uniform and is only introduced into the sealing area 430 where no vinyl tape has been applied. There are no air bubbles within the applied silicone. The airbag is then deflated and the vinyl tape is removed.

[0037] Fourth, the sealant liner 100 is slowly rotated on the rotating arm while an infrared heating lamp is applied approximately 1 inch from the silicone surface. The sealant liner 100 is left to cure for approximately 10-20 minutes or until the silicone no longer feels sticky. If the silicone coating is still liquid or soft, the sealant liner 100 is kept rotating to cure for a longer period. Once the silicone has cured sufficiently to remain in place without rotation, the sealant liner 100 is moved to a clean location to complete curing overnight at room temperature.

[0038] Furthermore, the impregnation process of silicone on the fabric exterior 300 can be accomplished in a variety of ways, including applying a pre-formed, semi-cured silicone strip to the top surface 470 of the raised portion 440. The application process can include painting, spraying, coating, casting, injection molding, or immersing the sealing liner 100 in silicone material without inflating the sealing liner 100.

[0039] Successful stress and abrasion tests demonstrated that the sealing liner 100 will maintain a vacuum during use due to its durable sealing area 430. First, a vacuum test was performed on the sealing liner 100 to establish a baseline for the vacuum level achieved in the sealing liner 100 and within the socket (vacuum reached 23 inches of mercury, vacuum held at 20 inches of mercury, test duration 24 hours). After establishing the baseline, the elastic material impregnated within the outer fabric layer 300 was gradually removed by abrasive force to monitor the resulting vacuum level. The first abrasion step removed a small layer of elastic material impregnated within the outer fabric layer 300 at the top surface 470 of the protrusion 440 (vacuum reached 22.5 inches of mercury, vacuum held at 20 inches of mercury, test duration 24 hours). No significant vacuum loss was observed. The second abrasion step removed a thicker layer of elastic material impregnated within the outer fabric layer 300, and again no significant vacuum loss was obtained (vacuum reached 18.5 inches of mercury, vacuum held at 17.5 inches of mercury, test duration 24 hours). The sanding process continued until, gradually, each raised portion 440 showed a significant loss of impregnated elastic material within the fabric exterior 300 (vacuum reached 23 inches of mercury, vacuum maintained at 20 inches of mercury, and test duration was 24 hours). No significant vacuum loss was obtained. During multiple tests of the sanding process, the loss of the sealing lining 100 never exceeded 4.5 inches of mercury, and on average never exceeded 2 inches of mercury.

[0040] When the amputee wears and inserts the limb into the socket used in conjunction with the vacuum system, the air volume within the socket and beneath the sealing layer is evacuated, thereby securing the stump within the socket. This invention therefore preferably reduces any possibility of a tourniquet effect caused by the vacuum process and provides high abrasion resistance.

[0041] This disclosure includes the contents contained in the appended claims as well as the foregoing description. While the invention has been described with a degree of particularity in its preferred form, it should be understood that the preferred form of this disclosure is done by way of example only, and many variations in the construction details and combinations and arrangements of the components may be made without departing from the spirit and scope of the invention.

[0042] The description of the present invention is now complete.

Claims

1. A suspension bushing configured to create a vacuum between the stump and the prosthesis socket, comprising: An elongated tubular body portion formed of a thermoplastic elastic material has a tubular thickness, a vertical axis, defines an open proximal region and a closed distal region, and has at least one sealing region; Each sealing region includes one or more protruding portions that project in a ring along the vertical axis; Each protrusion also has a top surface; The outer layer of fabric is bonded to the tubular body portion; and The sealing area is formed of an elastic material impregnated within the outer layer of the fabric at least on the top surface of the protrusion; The tubular body portion further includes at least one annular recess, the thickness of which is less than the thickness of the tubular portion, and is positioned near each protrusion along the vertical axis.

2. The suspension bushing according to claim 1, wherein the outer fabric layer has a uniform thickness.

3. The suspension bushing according to claim 1, wherein the open proximal region has a larger perimeter and volume than the closed distal region.

4. The suspension bushing of claim 1, wherein the tubular body portion is formed of a material selected from the group consisting of silicone, polyurethane, block copolymers, styrene block copolymer gels, controlled distribution polymers, and crystalline polymers.

5. The suspension bushing according to claim 4, wherein the tubular body portion has a thickness of 2-9 mm.

6. The suspension bushing according to claim 1, wherein each protrusion has a thickness of 3-20 mm.

7. The suspension bushing according to claim 1, wherein the elastic material of the sealing region is formed of a material selected from the group consisting of natural rubber, silicone, polyurethane, latex, polysulfide, vinyl, polyisoprene and styrene block copolymer gel.

8. The suspension bushing according to claim 1, wherein the sealing region is located near the closed distal region of the tubular body.

9. The suspension bushing of claim 1, wherein the layer of the sealing region is located near the open proximal region of the tubular body.

10. The suspension bushing of claim 1, wherein the elastic material of the sealing area is only partially impregnated within the outer layer of the fabric.

11. A suspension bushing configured to create a vacuum between the stump and the prosthesis socket, comprising: The slender tubular body portion is formed of a thermoplastic elastic material and has an axis, defining an open proximal region and a closed distal region; One or more raised sealing portions extend circumferentially along the axis and have distal and proximal positions, each raised sealing portion also having a thickness, wherein the thickness is greatest between the distal and proximal positions; The raised sealing portion also has a top surface; The tubular main body is covered by a fabric outer layer. The sealing area is formed of an elastic material impregnated within the outer layer of the fabric at least on the top surface of the raised sealing portion; The tubular body portion further includes at least one annular recess, the thickness of which is less than the thickness of the tubular body portion and is positioned along the axis near each raised sealing portion.

12. The suspension bushing according to claim 11, wherein the outer fabric layer has a uniform thickness.

13. The suspension bushing of claim 11, wherein the open proximal region has a larger perimeter and volume than the closed distal region.

14. The suspension bushing of claim 11, wherein the tubular body portion is formed of a material selected from the group consisting of silicone polyurethane, block copolymers, styrene block copolymer gels, controlled distribution polymers, and crystalline polymers.

15. The suspension bushing according to claim 11, wherein the tubular body portion has a thickness of 2-9 mm.

16. The suspension bushing according to claim 11, wherein each raised sealing portion has a thickness of 3-20 mm.

17. The suspension bushing of claim 11, wherein the elastic material of the sealing region is formed of a material selected from the group consisting of natural rubber, silicone, polyurethane, latex, polysulfide, vinyl, polyisoprene and styrene block copolymer gel.

18. The suspension bushing of claim 11, wherein the sealing region is located near the closed distal region of the tubular body.

19. The suspension bushing of claim 11, wherein the sealing region is located near the open proximal region of the tubular body.

20. The suspension bushing of claim 11, wherein the elastic material portion of the sealing area is impregnated within the outer layer of the fabric.

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