Prosthetic liner and method for producing same

Abstract

The invention relates to a prosthetic liner having a main body which has: - a closed distal end, - an open proximal end opposite the distal end, - a longitudinal axis which extends from the distal end to the proximal end, and - a circumferential wall which connects the distal end to the proximal end and encloses the longitudinal axis, wherein the liner has a peripheral envelope line along which an envelope portion is connected to a distal portion of the circumferential wall, wherein the envelope portion is designed such that a distance of the envelope portion from the longitudinal axis becomes smaller as the distance from the envelope line increases.

Description

[0001]Ottobock SE & Co. KGaA Attorney file: Max-Näder-Straße 15 0108-1970 PCT-1 37115 Duderstadt Germany Date: September 23, 2024 Prosthetic liner and method for its production The invention relates to a prosthetic liner with a base body that has a closed distal end, an open proximal end opposite the distal end, a longitudinal axis that extends from the distal end to the proximal end, and a circumferential wall that connects the distal end to the proximal end and surrounds the longitudinal axis. The invention also relates to a method for producing such a prosthetic liner. Prosthetic liners are worn between a prosthetic socket and the amputation stump and fulfill various tasks. On the one hand, they serve as padding. The amputation stump is exposed to immense stresses, especially in leg prostheses, and often has sensitive sections of soft tissue.To give the prosthesis, which is to be attached to the amputation stump, sufficient support and stability, a prosthetic socket is used, to which the other prosthetic components, such as a prosthetic knee or a prosthetic foot, can be arranged. This prosthetic socket is made of a rigid material, such as carbon, and is usually individually adapted to the amputation stump. The prosthetic liner therefore acts as padding and ensures a more comfortable and pain-free wearing experience. The prosthetic liner is also used to attach the prosthetic socket to the amputation stump. The prosthetic liner has a base body made of an elastic material, such as polyurethane or silicone. To apply it to the amputation stump, it is folded over so that its inner side, which is intended for application to the amputation stump, is on the outside. Alternatively, it can also be rolled up. To apply it, the FR / FR - PD003 / 20.10 The prosthetic liner is applied to the distal end of the amputation stump and then rolled proximally so that it fits snugly against the amputation stump. The prosthetic liner expands elastically, creating a compression effect on the amputation stump. The inner side of the prosthetic liner, which rests against the skin of the amputation stump in this state, preferably adheres well to the amputation stump, so that the prosthetic liner fits firmly against the amputation stump. The prosthetic socket is attached to the prosthetic liner. Various methods are known from the state of the art for this. Preferably, the amputation stump, fitted with the prosthetic liner, is inserted into the prosthetic socket, and a vacuum is created in the space between the inner wall of the prosthetic socket and the outer wall of the prosthetic liner, which holds the prosthetic socket to the prosthetic liner.This has the advantage that the holding force created by the negative pressure is exerted on as large a portion of the amputation stump as possible. It is important that the space to which the negative pressure is to be applied is sealed airtight proximally so that the negative pressure, once created, can be maintained for as long as possible. For this purpose, prosthetic liners with sealing lips are known from the prior art. These are arranged on the outside of the prosthetic liner and, when applied, rest against the inner wall of the prosthetic socket. In this case, the space to which the negative pressure is to be applied is limited proximally by the sealing lip. In order to exert the holding force created by the negative pressure on as large a portion of the amputation stump as possible, the prior art attempts to arrange the sealing lip as far proximally as possible on the prosthetic liner.WO 2009 / 062489 A1 discloses a prosthetic liner for vacuum sockets in which the portion of the amputation stump on which the holding force is exerted is maximized. The prosthetic liner is double-walled, with an inner liner and an outer liner, whereby the outer liner can be folded over the proximal edge of the prosthetic socket when in place. Suitable measures ensure an airtight connection between the outside of the prosthetic socket in the region of its proximal edge and the folded portion of the outer liner. The surface on which the holding force is exerted in this embodiment is formed by the entire surface of the prosthetic liner covered by the prosthetic socket. DE 102011105488 B4 describes a further development in which the line along which the outer liner can be folded follows the course of the socket edge, which is intended to create a more comfortable wearing experience.A disadvantage is that only a small part of the prosthetic liner can be folded over the edge of the prosthetic socket, but this small part is responsible for sealing the space between the outer side of the prosthetic liner and the inner wall of the prosthetic socket. The invention is therefore based on the object of specifying a prosthetic liner and a method for its production with which a better sealing of the space can be achieved. The invention solves the stated object by a prosthetic liner according to the preamble of claim 1, which is characterized in that the liner has a circumferential fold-over line along which a fold-over portion is connected to a distal portion of the peripheral wall, wherein the fold-over portion is designed such that a distance of the fold-over portion from the longitudinal axis decreases with increasing distance from the fold-over line.It is common practice in the art for a prosthetic liner to taper towards its distal end. This is due to the anatomy of the amputation stump, where this is usually also the case. This taper is best illustrated by looking at cross-sections of the liner taken perpendicular to the longitudinal axis. A taper of the liner towards the distal end means, for example, that the circumference of the liner in the respective cutting plane becomes smaller the closer the cutting plane is to the distal end. In these cross-sections, the wall of the main body of the prosthetic liner forms a closed line, which is circular in the simplest case. However, this is not necessary. Liners are also known from the prior art in which the wall has an oval or irregular shape. In all cases, however, it forms a closed line.Particularly in the case where the liner is individually adapted to the amputation stump and its contour, the closed line formed by the wall of the main body of the prosthetic liner in these cross-sections can be very irregular and individually designed. Alternatively or additionally, a taper of the liner towards the distal end means that the area enclosed by this closed line formed by the wall of the prosthetic liner in these cross-sections is smaller the closer the cutting plane is to the distal end. Such a taper does not necessarily mean that the length of the circumference of the liner and / or the area enclosed by the wall line must be a strictly mathematically monotonic function. It is quite possible that the liner has bulges or dents that result in some sections lacking the taper defined above.It is important, however, that this taper is present in the area of ​​the turn-up line. This means that at least at a distance from the turn-up line in the cross-section taken at this distance perpendicular to the longitudinal axis, the circumference of the base body and the surface area of ​​the surrounding area are smaller than directly at the turn-up line. Liners are known from the prior art in which the liner continues to widen with increasing distance from its distal end. This means that the turn-up portion also widens with increasing distance from the turn-up line. If the turn-up line lies in one of the cross-sectional planes described here, the turn-up portion tapers in the solution according to the invention.Because the distance of the folded portion from the longitudinal axis decreases with increasing distance from the fold line, the sealing of the space between the outer side of the prosthetic liner and the inner wall of the prosthetic socket is improved. This is because the folded portion, which in this state conforms to the outer side of the prosthetic socket, is pressed against the outer side of the prosthetic socket with greater force. This achieves a better sealing effect. However, the fold line preferably does not lie in such a cross-sectional plane perpendicular to the longitudinal axis; instead, the individual points on the fold line are at different distances from the distal end of the base body. This is referred to as an undulating fold line.In such prosthetic liners there are cross-sectional planes perpendicular to the longitudinal axis which are intersected twice by the foldover line, so that one part is located proximal and another part distal to the foldover line. In these cases it is not meaningful to speak of a tapering or widening of the prosthetic liner. What is important is that the distance of the foldover portion, i.e. the wall of the base body in this area, from the longitudinal axis decreases with increasing distance from the foldover line. This is regardless of whether the foldover line is at a constant distance from the distal end of the base body, i.e. lies completely in a cutting plane perpendicular to the longitudinal axis. When the prosthetic liner is applied, the foldover portion is preferably in a first position in which it extends proximally from the foldover line.In this first position, the folded portion causes the least disruption when the prosthetic liner is applied, which is usually done by unrolling the prosthetic liner onto the amputation stump. The prosthetic liner is first rolled up like a stocking when not in use, which can also be referred to as winding it up. In this rolled-up state, the distal end of the amputation stump is brought into contact with the distal end of the prosthetic liner and the prosthetic liner is then unrolled onto the amputation stump. Before rolling up the prosthetic liner, the folded portion is preferably brought into the first position, where it extends proximally from the folded line. Once the amputation stump is positioned in the prosthetic liner, both are arranged in the prosthetic socket.Preferably, the folded portion is then folded over along the fold line so that it is in a second position in which it extends distally from the fold line. Since this folding over occurs after the amputation stump with the prosthetic liner has been arranged in the prosthetic socket, the folded portion lies radially outside the prosthetic socket. In other words, a proximal region of the prosthetic socket is located between the distal portion of the peripheral wall of the prosthetic liner and the folded over folded portion. The distance of the folded portion from the longitudinal axis decreases with increasing distance from the fold line, regardless of whether the folded portion is in the first position in which it extends proximally from the fold line or in the second position in which it extends distally from the fold line.This is at least true when the prosthetic liner is relaxed and in an upright position. In such a position, the prosthetic liner assumes its maximum volume without the base body, which is usually made of an elastic material, being elastically stretched. If the liner is manufactured using a dipping process, for example, this upright position corresponds to the contour of the molded article that is dipped into the base body material. If the prosthetic liner is manufactured using a casting process, the upright position corresponds to the volume of the casting mold available for the base body material. In practice, this position is difficult to achieve because the prosthetic liner usually does not have sufficient stability.One can imagine achieving this upright position by filling (inflating) the liner with gas while standing on its distal end until the gas pressure inside the prosthetic liner, in which the amputation stump is to be positioned, is so high that the interior of the prosthetic liner takes up its maximum volume. The pressure difference between the gas pressure inside the prosthetic liner and the ambient pressure is not sufficient to elastically stretch the elastic material of the base body. To apply it, the prosthetic liner is first rolled up with its base body or turned inside out, which means that its inner side, with which it is supposed to lie against the skin of the amputation stump when applied, is on the outside.In this prepared state, the distal end of the amputation stump is placed against the distal end of the prosthetic liner, and the prosthetic liner is rolled out onto the amputation stump so that the amputation stump is within the prosthetic liner and the inner side of the prosthetic liner comes into contact with the skin of the amputation stump. The amputation stump, with the prosthetic liner applied in this way, is then inserted into the prosthetic socket. The folded portion of the prosthetic liner is then folded over the distal edge of the prosthetic socket along the circumferential fold line, bringing it into contact with the outer side of the prosthetic socket. This prevents air from penetrating the space between the folded portion of the prosthetic liner and the outer wall of the prosthetic socket. The folded portion is preferably a proximal portion of the base body.This design has the advantage that the base body can be formed as a single piece, and the turn-up portion can be manufactured and produced together with the remaining portion of the base body, which can be referred to as the distal portion. Alternatively, the turn-up portion is designed as a cuff that is attached, preferably glued, pressed, or welded to the peripheral wall along the turn-up line. If the turn-up portion is glued or welded to the peripheral wall of the base body, it is preferably manufactured beforehand as a separate component, for example cast or produced using an additive manufacturing process, for example 3D printing. If the turn-up portion is printed, it is preferably not manufactured beforehand as a separate component. Instead, the base body of the prosthetic liner is arranged in the device for the additive manufacturing process, for example in the 3D printer.The folded portion is then pressed onto the existing base body. In a preferred embodiment, the folded line does not have a constant distance from the distal end of the liner. This makes it possible to follow correspondingly shaped proximal end edges of the prosthetic socket and to provide a prosthetic liner even for custom-made prosthetic sockets, the folded portion of which can be folded over the proximal edge of the prosthetic socket. If the folded line does not have a constant distance from the distal end of the liner, this means in particular that individual points on the folded line are at different distances from the distal end and the folded line therefore does not lie in a single sectional plane of the prosthetic liner that is perpendicular to the longitudinal axis of the prosthetic liner.The turn-up portion preferably has a socket contact surface for engagement with a prosthetic socket and an outer surface opposite the socket contact surface, wherein the distal portion of the peripheral wall has an inner surface for engagement with an amputation stump and an outer surface opposite the inner surface, wherein an outer surface of the peripheral wall and a textile or friction-reducing coating are arranged on the outer surface of the turn-up portion. The textile or friction-reducing coating is preferably arranged everywhere on the prosthetic liner where it comes into contact with other elements or components and where no adhesion is desired. This is the case, on the one hand, on the outer surface of the peripheral wall in the distal portion of the peripheral wall. The distal portion of the peripheral wall is the part of the peripheral wall that is located between the distal end of the base body and the turn-up line.The outer surface of this part of the peripheral wall comes into contact with the inside of the prosthetic socket when the prosthesis is in place. The lowest possible static friction between the outer surface of the peripheral wall and the inside of the prosthetic socket is particularly desirable when putting on and taking off the prosthesis. On the other hand, the outer surface of the folded portion can also come into contact with other elements, such as items of clothing, such as trousers, worn by the wearer of the prosthetic system, of which the prosthetic liner described here is a part. The outer surface of the folded portion is located on the outside, i.e., on the side facing away from the amputation stump, when the folded portion is folded over, preferably over the proximal edge of a prosthetic socket.In particular, if the turn-up portion is part of the base body, the textile or friction-reducing coating is located in the distal portion of the base body, i.e., between the distal end of the base body and the turn-up line on the outer surface of the peripheral wall, and in the proximal portion of the base body, which is located proximal to the turn-up line and forms the turn-up portion, on the opposite side, which only forms the outer surface of the turn-up portion when the turn-up portion is turned over. A friction-reducing coating is understood to be any coating that reduces the static friction between the surface to which it is applied and another element, for example, a piece of clothing or the prosthetic socket. Consequently, adhesion is lower with the applied coating than without it.Preferably, the distance of the peripheral wall from the longitudinal axis decreases, at least within a mirror section, with increasing distance from the fold line to the same extent as the distance of the fold portion from the longitudinal axis, with the mirror section directly adjoining the fold line. Preferably, the distal portion of the base body and the fold portion are manufactured using an additive manufacturing process. If the fold portion is the proximal portion of the base body, the entire base body is preferably manufactured in a single process step using the additive manufacturing process.If the turn-up portion is not the proximal portion of the base body, the base body is preferably manufactured first, which is then placed in the device for carrying out the additive manufacturing process, for example, the 3D printer, so that the turn-up portion is printed onto the existing base body. The 3D printing process makes it particularly easy to individually adapt the prosthetic liner to the needs of the future wearer of the prosthetic liner. The production of any turn-up line and the reduction of the distance from the axis in the area proximal to the turn-up line are also particularly easy to achieve in this way.Furthermore, this makes it particularly easy to individualize the turn-up portion and, for example, to manufacture the turn-up portion using a material with a different Shore hardness than the material for the distal portion of the prosthetic liner, or to manufacture special elements, such as thickened portions for additional form-fitting with the prosthetic socket. The invention further achieves the stated object by a method for manufacturing a prosthetic liner of the type described here, wherein the distal portion of the base body and the turn-up portion are manufactured at least partially by means of an additive manufacturing method from at least one manufacturing material that is introduced into a support material in a flowable state and then cures. Such methods are known from the prior art, for example under the term "rapid liquid printing," and are used to manufacture prosthetic liners.This is described, for example, in DE 102018124516 A1 and WO 2020 / 069817 A1, the content of which is incorporated in its entirety by reference into the content of the present description. Preferably, the turn-up portion is produced in the form of a cuff and, after the turn-up portion and the distal portion of the base body have cured, is fastened to the peripheral wall, preferably by gluing or welding. In this case, too, it is advantageous to produce both the base body and the turn-up portion in the form of the cuff using a 3D printing process or another additive manufacturing process of the type described here. Advantageously, the following steps are carried out to fasten the turn-up portion to the peripheral wall: a. Arranging the base body on a core, b.Adhering a textile to the outer side of the distal portion of the peripheral wall by means of an adhesive layer such that the adhesive layer protrudes proximally beyond the proximal edge of the textile, c. Applying adhesive to the textile in a proximal region of the textile such that the adhesive forms an adhesive strip with the portion of the adhesive layer protruding beyond the proximal edge of the textile, and d. Adhering the turn-up portion to the adhesive strip. Preferably, after adhering the turn-up portion, a textile is applied to the outer surface of the turn-up portion. As an alternative to a turn-up portion produced as a cuff, the turn-up portion is preferably formed as a proximal portion of the base body. In this case, the base body is preferably provided with a distal textile part and a proximal textile part, wherein the following steps are carried out: A. Arranging the base body on a core, B.Arranging the distal textile part on the outside of the peripheral wall in the distal portion, C. Turning over the proximal portion so that it forms the turned-over portion, D. Arranging the proximal textile part on the outside of the turned-over portion. Preferably, the distal textile part and the proximal textile part are glued to the peripheral wall of the base body when arranged on the peripheral wall. In a further embodiment of the method, the base body is provided with a textile which has a proximal textile section and a distal textile section, the following steps being carried out: i. Producing the distal portion of the peripheral wall by means of the additive manufacturing process, ii. Arranging the distal textile section on the distal portion of the peripheral wall, iii.Arranging the proximal portion of the peripheral wall as a turn-up portion on the proximal textile section, wherein the proximal portion of the peripheral wall is preferably produced by means of an additive manufacturing process and arranged during or after the turn-up on the proximal textile section. Preferably, in the region of the turn-up line, the textile is arranged between the proximal portion of the side wall and the distal portion of the side wall. The arrangement of a textile on the peripheral wall of a prosthetic liner has long been known from the prior art. The textile usually consists of several pieces of textile that are cut to size and then joined together, in particular sewn. These seams can be annoying for the wearer of the prosthetic socket, especially in the case of a peripheral wall with a small thickness. This is particularly the case at locations where many of these seams meet, for example at the distal end of the prosthetic liner.It is therefore advantageous if the individual textile pieces are not sewn together, but welded together. This avoids seams and large areas of overlapping textile pieces. The textile pieces are preferably made, at least in the connecting areas where they are to be joined to another textile piece by welding, from a material that can be brought into a softer state, preferably a liquid state in which it is deformable. If both textile pieces to be welded together are made of such a material in the respective connecting area, they can be joined together in the softer state. Such materials are, for example, thermoplastic materials, for example textiles made from thermoplastic fibers or fibers coated with a thermoplastic material.In order to convert these materials into a softer, i.e. joinable, state, energy is supplied, for example in the form of heat or ultrasonic waves. The material of the two pieces of textile to be joined softens in this way and the textile pieces bond. After cooling, the two pieces of textile are bonded to one another. The weld seam created in this way is preferably covered, preferably glued, with a cover strip made of an elastic material. The cover strip consists, for example, at least predominantly, preferably entirely, of a material that is at least as elastic as the joined textile pieces. The cover strip significantly increases the mechanical stability of the weld seam, particularly with regard to tensile loads, so that tensile forces can be transferred much more effectively from one piece of textile to the other.The textile to be arranged on the peripheral wall of the prosthetic liner is preferably made from several pieces of textile, with some, particularly preferably all, of the weld seams thus created being covered by a cover strip. The textile produced in this way is then connected, for example glued, to the peripheral wall of the prosthetic liner. For this purpose, the textile is preferably arranged on the peripheral wall such that the cover strip(s) lie on the side of the textile facing the peripheral wall. In the connected state, for example in the finished prosthetic liner, the cover strip(s) therefore lie between the material of the peripheral wall of the base body and the material of the interconnected textile parts. Alternatively or additionally, the textile can also be connected directly to the liner material using a casting or dipping process.The textile is applied to a mold, for example, and the liner material is then added. For this purpose, the liner material is poured onto the mold, for example, or the mold with the applied textile is dipped into the liner material. A direct connection is created between the liner material and the textile during the manufacturing process of the prosthetic liner. This is a sensible and advantageous design not only for prosthetic liners of the type described here, but generally for prosthetic liners with a base body that has a closed distal end, an open proximal end opposite the distal end, a longitudinal axis extending from the distal end to the proximal end, and a circumferential wall connecting the distal end to the proximal end and surrounding the longitudinal axis.A textile composed of several welded textile pieces is arranged, preferably glued, on at least part of the peripheral wall, preferably on the entire peripheral wall. Such a prosthetic liner represents a separate invention. All embodiments of a prosthetic liner described here are also advantageous for a prosthetic liner according to this separate invention and are preferably combined individually or in any desired combination with this separate invention. Some embodiments of the present invention are explained in more detail below with the aid of the attached figures.Figures 1 to 3 show various methods for producing a prosthetic liner according to exemplary embodiments of the present invention. Figure 4 shows a prosthetic liner according to a further exemplary embodiment of the present invention at different stages during application. Figure 5 shows a schematic representation of a prosthetic liner according to a further exemplary embodiment of the present invention. Figure 6 shows a schematic sectional representation of a prosthetic liner in a prosthetic socket. Figure 7 shows a schematic sectional representation through a prosthetic liner according to a further exemplary embodiment of the present invention. Figures 8 and 9 show schematic representations of various method steps. Figures 1 to 3 schematically show different methods with which a prosthetic liner according to an exemplary embodiment of the present invention can be produced.In Figure 1, top left, it is shown that a base body 2 of a prosthetic liner is pulled over a core 4. The core 4 can be manufactured individually for the respective prosthetic liner or designed as a standard core. The core 4 can also be designed so that its geometric shape and contour can be changed in order to accommodate different designs, such as sizes and / or contours, of the prosthetic liner. This can be achieved, for example, if the core 4 has several elements that can move relative to one another, such as metal pins or molded parts, by means of which the geometric shape and contour can be changed. The base body 2, which is preferably made entirely, but at least partially, of an elastic material, is elastically stretched in the process. A distal end 6 of the base body 2 is arranged on top of the core 4.From there, the cross-section of the base body 2 widens until a widest point is reached. From there, the base body 2 tapers with increasing distance from the distal end 6. The middle illustration in the top row in Figure 1 shows that an adhesive layer 8 is applied to the distal portion of the peripheral wall 10. The distal portion extends from the distal end 6 of the base body 2 to the widest point. A textile 12 is applied to this distal portion of the peripheral wall 10, shown in the top right of the illustration. This textile 12, however, extends over more than just the distal portion of the peripheral wall 10 provided with the adhesive layer 8, but is not connected to the base body 2 in the section beyond that. This portion extending beyond the adhesive layer 8 can also be referred to as the loose portion 14. The next work step is shown in the middle row on the left.The textile 12 is trimmed. The loose portion 14 is severed, for example, with scissors, so that the remaining part of the textile 12 is fully bonded to the base body 2 by the adhesive layer 8. Adhesive 16 is then applied to the proximal region of the textile 12 such that the adhesive 16 is bonded to the part of the adhesive layer 8 that protrudes beyond the proximal edge of the textile 12, forming a common adhesive strip. In the next step, shown in the middle right illustration, a fold-over portion 18 is arranged on this adhesive strip. For both this step and the preceding step, in which the adhesive 16 is applied, an enlarged section is provided in the illustration for the sake of clarity.In the illustrated embodiment, the turn-up portion 18 extends distally from the turn-up line 20, which corresponds to the position of the adhesive strip, after being adhered to the adhesive strip. It is therefore in the second position. It can be seen that, in the illustrated embodiment, the turn-up portion 18 tapers with increasing distance from the turn-up line 20. In other words, with increasing distance from the turn-up line 20, the distance of the turn-up portion 18 from a longitudinal axis, which is not shown but which connects the closed distal end 6 to the opposite open proximal end within the base body 2, decreases. The third line of Figure 1, in the left-hand illustration, shows that a further adhesive layer 8 is applied to the turn-up portion 18 and a proximal portion 22 of the peripheral wall 10 of the base body 2.In the illustration shown, the proximal portion 22 extends downwards, i.e. proximally, from the fold line 20. In the lower middle illustration of Figure 1, it can be seen that a further textile 12 is glued onto this further adhesive layer 8, which in the exemplary embodiment shown has two loose portions 14, one of which extends distally (upwards in Figure 1) and one proximally (downwards in Figure 1). These are trimmed in the last method step shown, as shown bottom right, i.e. cut off with scissors, for example. Cut edges of a textile 12 that arise at a point where the base body 2 projects beyond the textile 12, as shown, for example, in the left illustration in the middle row of Figure 1, are difficult to accomplish from a technical perspective and are often sloppy.The method shown here offers the advantage that such a cut edge is concealed by gluing on the turn-up portion 18. All other cut edges can be produced with high quality because the textile 12 extends beyond the base body 2. Figure 2 shows another possibility for producing a prosthetic liner according to an embodiment of the present invention. Again, the base body 2 is applied to the core, with the turn-up portion 18 being separated from the base body 2 and arranged on the core in the form of a cuff. This turn-up portion is removed from the core before, as shown in the second illustration, an adhesive layer 8 is applied to the distal portion of the peripheral wall 10. In the next method step, the textile 12, which again has a loose portion 14, is applied thereto.Unlike the process according to Figure 1, however, this is not trimmed or cut off, but provided with a further adhesive layer 8, as shown in the right-hand illustration in the first line of Figure 2. In the next process step, the turn-up portion 18 in the form of the cuff is glued to this further adhesive layer 8. This results in only a single textile 12 being present, which extends over both the distal portion of the peripheral wall 10 and the turn-up portion 18. It can also be seen that the turn-up portion 18 is produced in the first position, in which it extends proximally from the turn-up line 20, i.e. downwards in Figure 2. The turn-up line 20 again corresponds to the point of the largest diameter of the core 4, which at the same time lies between the distal portion of the peripheral wall 10 and the turn-up portion 18. In the last process step, which is shown in Figure 2, the core 4 is removed.Figure 3 shows a further embodiment of a method according to an embodiment of the present invention. Again, in the first method step, the base body 2 is arranged on the core. In the second method step, an adhesive layer 8 is applied, to which the textile 12 with the loose portion 14 is glued in the following method step. The loose portion 14 is trimmed in the following method step, i.e., removed with scissors. Then, according to the first illustration in the second line of Figure 3, the turn-up portion 18, which in this case is part of the base body 2, is folded from the first position in which it was previously located into the second position. It can be seen that in the illustration in the second line of Figure 3, it extends distally from the turn-up line 20, i.e., upwards in Figure 3. In this state, it is provided with a further adhesive layer and another textile, which is then trimmed.Figure 4 shows schematically different sectional views. On the left, a prosthetic liner according to an embodiment of the present invention is shown. Here, the distal end 6 is shown at the bottom. Extending upwards from the distal end 6 is the distal portion of the peripheral wall 10, the cross-section of which increases with increasing distance from the distal end 6. The fold-over line 20 is located at the point of the largest diameter. Proximally, i.e. at the top in Figure 4, the fold-over portion 18 extends from this as a portion of the base body 2. This extends proximally from the fold-over line 20 and is therefore in the first position. In the middle of Figure 4, this liner is arranged in a prosthetic socket 24.The right-hand illustration in Figure 4 shows the situation in which the turn-up portion 18 has been turned over from the first position to the second position and now extends distally from the turn-up line 20, i.e. downwards in Figure 4. Figure 5 schematically shows this situation with an undulating turn-up line 20. The prosthetic liner is located in the prosthetic socket 24 and the turn-up line 20 has a varying distance from the distal end 6. The turn-up portion 18 is turned over along this undulating turn-up line 20. Figure 6 shows a corresponding situation in a schematic sectional illustration. The main body 2 of the prosthetic liner is arranged inside the prosthetic socket 24. Only the distal portion is located within the prosthetic socket 24. This distal portion is provided with the textile 12, which in this area is therefore located between the main body 2 and the prosthetic socket 24.The turn-up portion 18 is folded over into the second position along the turn-up line 20 and now extends distally from this turn-up line 20. The turn-up portion 18 is also provided with a textile 12 on its outer side, but rests with a side not provided with a textile, the socket contact surface, on the outer side of the prosthetic socket 24, thereby achieving good adhesion. Figure 7 shows a section through a prosthetic liner according to a further exemplary embodiment of the present invention. It has an inner liner 26 which is bonded to an outer liner 28 via an adhesive layer 8. This forms the base body 2 of the liner shown. In the proximal region shown on the left, the outer liner 28 forms the turn-up portion 18. A textile 12 is located between the turn-up portion 18 and the proximal end of the inner liner 26, just as it is on the outer side of the distal portion of the outer liner 28.Figures 8 and 9 show steps in the production of the textile 12. Figure 8 shows two pieces of textile 30 which are placed on top of one another and joined together by the device schematically shown at the top right in Figure 8. The device is a so-called "cut and seal" device with which the two pieces of textile 30 are joined together and then cut to size. The first part of the device shown on the left has a guide wheel 32 and a wheel 34 for welding. Ultrasonic waves generated by a generator (not shown) are transmitted via this wheel 34 to the two pieces of textile 30, welding the two pieces of textile 30 together. In the following arrangement of the device shown on the right, a guide wheel 32 is again present, which now interacts with a cutting wheel 36, by means of which the two now joined pieces of textile 30 are cut to size.The textile 12 shown in the lower part of Figure 8 is created. Further process steps are shown in Figure 9. The textile 12 is composed of the two textile pieces 30 which are joined together by a weld seam 38. The textile 12 is applied to a blank so that it has the desired shape. In this state, which corresponds to the second illustration from the left in Figure 9, the two textile pieces 30 are positioned relative to one another in the arrangement shown below, with the weld seam 38 in the center of the illustration. In this state, the textile 12 is guided between two guide wheels 32, during which a cover strip 40 is applied. This cover strip is made adhesive using hot air supplied through a nozzle 42 and is pressed onto the textile 12 between the two guide wheels 32.This creates the situation shown on the right in the figure, in which the textile 12 has a weld seam 38 that is covered by the cover strip 40. List of reference symbols 2 base body 4 core 6 distal end 8 adhesive layer 10 peripheral wall 12 textile 14 loose part 16 adhesive 18 turn-up part 20 turn-up line 22 proximal part 24 prosthesis socket 26 inner liner 28 outer liner 30 textile piece 32 guide wheel 34 wheel 36 cutting wheel 38 weld seam 40 cover strip 42 nozzle.

Claims

Ottobock SE & Co. KGaA Attorney's file: Max-Näder-Straße 15 0108-1970 PCT-1 37115 Duderstadt Germany Date: September 23, 2024 Patent claims 1. Prosthetic liner with a base body (2) which has - a closed distal end (6), - an open proximal end opposite the distal end (6), - a longitudinal axis which extends from the distal end (6) to the proximal end, and - a peripheral wall (10) which connects the distal end (6) to the proximal end and surrounds the longitudinal axis, characterized in that the liner has a circumferential turn-up line (20), along which a turn-up portion (18) is connected to a distal portion of the peripheral wall (10), wherein the turn-up portion (18) is designed such that a distance of the turn-up portion (18) from the longitudinal axis increasing distance from the transition line (20). 2.Prosthetic liner according to claim 1, characterized in that the turn-up portion (18) is a proximal portion (22) of the base body (2).

3. Prosthetic liner according to claim 1, characterized in that the turn-up portion (18) is designed as a sleeve that is attached, preferably glued, pressed, or welded, to the peripheral wall (10) along the turn-up line (20).

4. Prosthetic liner according to one of the preceding claims, characterized in that the turn-up line (20) is not at a constant distance from the distal end (2) of the prosthetic liner. NVA / FR - PD002 / 20.

10. - 2- 5. Prosthetic liner according to one of the preceding claims, characterized in that the turn-up portion (18) has a socket contact surface for engagement with a prosthetic socket (24) and an outer surface opposite the socket contact surface, and the distal portion of the peripheral wall (10) has an inner surface for engagement with an amputation stump and an outer surface opposite the inner surface, wherein a textile (12) or a friction-reducing coating is arranged on the outer surface of the peripheral wall (10) and on the outer surface of the turn-up portion (18).

6. Prosthetic liner according to one of the preceding claims, characterized in that the distance of the peripheral wall (10) from the longitudinal axis decreases, at least within a mirror section, with increasing distance from the turn-up line (20) by the same amount as the distance of the turn-up portion (18) from the longitudinal axis, wherein the mirror section directly borders the turn-up line (20).Prosthetic liner according to one of the preceding claims, characterized in that the distal portion of the peripheral wall (10) and the turn-up portion (18) are produced by means of an additive manufacturing process.

8. Method for producing a prosthetic liner according to one of the preceding claims, characterized in that the distal portion of the peripheral wall (10) and the turn-up portion (18) are produced at least partially by means of an additive manufacturing process from at least one production material which is introduced into a support material in a flowable state and then hardens.

9. Method according to claim 8, characterized in that the turn-up portion (18) is produced in the form of a sleeve and, after the turn-up portion (18) and the distal portion of the peripheral wall (10) have hardened, is fastened to the peripheral wall (10), preferably by adhesive bonding or welding. - 3- 10. The method according to claim 9, characterized in that the following steps are carried out to fasten the turn-up portion (18) to the peripheral wall (10): a. Arranging the base body (2) on a core (4), b. Adhering a textile (12) to the outside of the distal portion of the peripheral wall (10) by means of an adhesive layer (8) such that the adhesive layer (8) protrudes proximally beyond a proximal edge of the textile (12), c. Applying adhesive (16) to the textile (12) in a proximal region of the textile (12) such that the adhesive (16) forms an adhesive strip with the portion of the adhesive layer (8) protruding beyond the proximal edge of the textile (12), d. Adhering the turn-up portion (18) to the adhesive strip.

11. Method according to claim 10, characterized in that after the gluing of the cover portion (18), a textile (12) is glued to the outer surface of the cover portion (18).Method according to claim 8, characterized in that the base body (2) is provided with a distal textile part and a proximal textile part, the following steps being carried out: A. Arranging the base body (2) on a core (4) B. Arranging the distal textile part on the outside of the peripheral wall (10) in the distal portion C. Folding over the proximal portion (22) so that it forms the folded portion (18), D. Arranging the proximal textile part on the outside of the folded portion (18).

13. Method according to claim 12, characterized in that the distal textile part and the proximal textile part are glued to the peripheral wall (10) of the base body (2) during arrangement. - 4- 14. The method according to claim 8, characterized in that the base body (2) is provided with a textile (12) which has a proximal textile section and a distal textile section, the following steps being carried out: i. producing the distal portion of the peripheral wall (10) by means of the additive manufacturing process ii. arranging the distal textile section on the distal portion of the peripheral wall (10) iii. arranging the proximal portion of the peripheral wall (10) as a turn-up portion (18) on the proximal textile section, wherein preferably the proximal portion (22) of the peripheral wall (10) is produced by means of an additive manufacturing process and is arranged on the proximal textile section during or after the process.

15. Method according to claim 14, characterized in that in the region of the turn-up line (20) the textile (12) is arranged between the proximal portion (22) of the peripheral wall (10) and the distal portion of the peripheral wall (10).

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