METHOD FOR PRODUCING A PROSTHETIC LINER AND SYSTEM CONSISTING OF PROSTHETIC LINER AND PROSTHETIC SOCKET

Abstract

The invention relates to a method for producing a prosthetic liner for insertion into a prosthetic socket, which comprises a receptacle having a distal end and a proximal edge for a residual limb and the prosthetic liner. Said The method comprises determining a sealing lip contour on the outer face of the prosthetic liner which corresponds to a height contour of the proximal edge of the prosthetic socket, or on the basis of available, known anatomic characteristics of the residual limb and arranging a sealing lipon the outer face of the prosthetic liner along the determined sealing lip contour.

Claims

1. A method for producing a prosthesis liner for use in a prosthesis socket which has a receiving space for a stump and the prosthesis liner, the prosthesis socket having a distal end and a proximal edge, said method having the following steps: a. determining a sealing lip profile on an outer face of the prosthesis liner corresponding to the profile of a height contour of the proximal edge of the prosthesis socket or based on existing, known anatomical characteristics of the stump; and b. arranging a sealing lip on the outer face of the prosthesis liner along the determined sealing lip profile.

2. The method as claimed in claim 1, wherein the height contour of the proximal edge of the prosthesis socket is detected before the sealing lip profile is determined.

3. The method as claimed in claim 1, wherein the prosthesis liner is additively manufactured, or wherein the sealing lip is fixed along the determined sealing lip profile.

4. The method as claimed in claim 1, wherein the sealing lip is arranged on the prosthesis liner in a manner offset in the distal direction with respect to the proximal edge of the prosthesis socket.

5. The method as claimed in claim 1, wherein the profile of the height contour is detected in the proximal-distal direction and/or the profile of a circumferential contour is detected over a circumference of the prosthesis socket.

6. The method as claimed in claim 1, wherein the sealing lip over a circumference of the prosthesis liner is arranged at the same distance in the proximal-distal direction from the proximal edge of the prosthesis socket.

7. The method as claimed in claim 1, wherein the sealing lip is arranged in a sealing lip region which is wider than the sealing lip and of which the proximal and distal border corresponds to the height contour of the proximal edge of the prosthesis socket.

8. The method as claimed in claim 7, wherein the sealing lip region is twice as wide as the sealing lip at its transition to a base body of the prosthesis liner.

9. The method as claimed in claim 1, wherein the height contour or a height and circumferential contour of the prosthesis socket is detected optically, a digital 3D model is created, and the sealing lip profile or the sealing lip profile and the sealing lip height is determined as a function of the detected height contour or of the detected circumferential and height contour.

10. The method as claimed in claim 9, wherein that the sealing lip height is determined as a function of a detected distance between an inner circumference of the prosthesis socket and an outer circumference of a stump that is to be inserted.

11. The method as claimed in claim 3, wherein the prosthesis liner is produced in a rapid liquid printing process.

12. A system composed of a prosthesis socket and of a prosthesis liner, wherein the prosthesis socket has a receiving space for a stump fitted with the prosthesis liner, the prosthesis socket has a distal end and a proximal edge, the proximal edge of the prosthesis socket has a height contour and a circumferential contour, and at least one sealing lip is formed or determined on the outer face of the prosthesis liner directed toward the prosthesis socket, and wherein the sealing lip profile of the at least one sealing lip corresponds, in the fully inserted state of the prosthesis liner, to the profile of the height contour of the prosthesis socket.

13. The system as claimed in claim 12, wherein when the prosthesis liner is in the fully inserted state, the prosthesis socket is designed with a closed wall distally with respect to the at least one sealing lip.

14. The system as claimed in claim 12, wherein the prosthesis socket is dimensionally stable.

15. The system as claimed in claim 12, wherein the at least one sealing lip is fastened or formed on a base body and has a non-uniform width over the circumference of the prosthesis liner.

16. The system as claimed in claim 12, wherein the sealing lip profile does not lie in one plane.

17. A prosthesis liner for the system as claimed in claim 12, wherein the prosthesis liner has at least one sealing lip which is formed or fastened on an outer face of the prosthesis liner and which forms a sealing lip profile in the shape of a three-dimensional curve.

18. The prosthesis liner as claimed in claim 17, wherein the sealing lip profile of the at least one sealing lip is designed to correspond to the profile of a height contour of a proximal edge of a prosthesis socket.

19. A method for producing a prosthesis liner for use in a prosthesis socket which has a receiving space for a stump and the prosthesis liner, the prosthesis socket having a distal end and a proximal edge, the method having the steps of: a. detecting a height contour of the proximal edge of the prosthesis socket; b. determining a sealing lip profile on an outer face of the prosthesis liner; and b. arranging a sealing lip on the outer face of the prosthesis liner along the determined sealing lip profile in a manner offset in the distal direction with respect to the proximal edge of the prosthesis socket, wherein the sealing lip profile corresponds to the profile of the height contour of the proximal edge of the prosthesis socket.

20. The method of claim 19, wherein the height contour or a height and circumferential contour of the prosthesis socket is detected optically, a digital 3D model is created, and the sealing lip profile or the sealing lip profile and a sealing lip height is determined as a function of the detected height contour or of the detected circumferential and height contour.

Description

[0024] An exemplary embodiment of the invention is explained in more detail below with reference to the accompanying figures, in which:

[0025] FIG. 1 shows a prosthesis liner on its own;

[0026] FIG. 2 shows a system composed of a prosthesis socket and of a prosthesis liner arranged thereon; and

[0027] FIG. 3 shows a schematic representation of a variant of the production method.

[0028] FIG. 1 shows a prosthesis liner 20 on its own, with a proximal edge 21 and a distal end region 22. The distal end region 22 is closed, and the proximal edge 21 circumferentially surrounds an access opening. The prosthesis liner 20 has a base body 25 with an outer face 23 and an inner face 24. The base body 25 is flexible and preferably elastic, at least in the circumferential direction. The inner face 24 of the base body 25 can be made of an adhesive polymer, for example silicone.

[0029] Alternatively, the inner face 24 can be completely or partially coated with an adhesive coating. The coating can be formed, for example, from a silicone or another polymer that adheres to the skin. The outer face 23 of the base body 25 can likewise be made of an elastomer or be at least partially coated with an elastomer. It is likewise possible that a textile is applied to the outer face 23 in order to equalize the pressure in a space between the prosthesis liner 20 and a prosthesis socket (not shown). Alternatively or in addition, elevations or channels can be arranged, for example formed or introduced or applied, on the outer face 23 in order to permit fluidic connections over the entire longitudinal extent, that is to say from distal to proximal, and all around the circumference.

[0030] Arranged on the base body 25 is a sealing lip 26 which forms a seal between the proximal region and the distal region of the prosthesis liner 20 in the inserted state in a prosthesis socket (not shown). The sealing lip 26 can be produced from an air-impermeable material or correspondingly coated, such that no air passes through the sealing lip 26. The sealing lip 26 can be made, for example, of a silicone or a polymer or be coated with such a material. One possible way of designing the sealing lip 26 is for it to be formed integrally with the base body 25, for example in the context of an additive manufacturing process, for example via the rapid liquid printing process, or by casting or during another primary forming process. The region located distally from the sealing lip 26 on the outer face 23 of the base body 25 can be provided with a structured surface, permitting a pressure distribution in regions spaced apart from one another. The structuring can be provided, for example, as a textile material, which can be glued on or laminated, or via channels and/or elevations on the outer face 23.

[0031] The sealing lip 26 protrudes radially from the base body 25 and is preferably elastic, such that the sealing lip 26 bears with its outer face, which faces away from the base body 25, on the prosthesis socket and presses against the latter. In the exemplary embodiment shown, the sealing lip 26 is not designed protruding perpendicularly from the outer face 23 of the base body 25, but is designed or arranged at an inclination. The inner face of the sealing lip 26, directed toward the base body 25, encloses between them an acute angle. In principle, it is also possible to provide a reverse orientation or to have the sealing lip 26 protruding perpendicularly. During the insertion of the prosthesis liner 20 into a prosthesis socket, the sealing lip is then generally folded back, such that an orientation is obtained in which the face of the sealing lip 26 oriented in the distal direction bears on the inner face of the prosthesis socket. If, in relation to the atmospheric pressure, there is a negative pressure in the volume sealed off by the sealing lip 26 between the prosthesis socket and the region located distally with respect to the sealing lip 26, the sealing lip 26 is pressed against the inner wall of the prosthesis socket, such that a self-intensifying sealing effect is established.

[0032] It will be seen from FIG. 1 that the proximal edge 21 of the prosthesis liner 20 is rectilinear or arranged in one plane, wherein the plane runs substantially perpendicular to the longitudinal extent of the prosthesis liner 20. By contrast, the sealing lip 26 does not run in a common plane, in particular not in a plane parallel or inclined with respect to the proximal edge 21 of the prosthesis liner 20, but instead along a three-dimensional curve that corresponds to the profile of the height contour of the prosthesis socket at the proximal edge thereof. The exemplary embodiment in FIG. 1 depicts a prosthesis liner 20 for a lower leg. The sealing lip 26 runs in the frontal region just below the patella and extends medially and laterally in the direction of the proximal edge 21. In the rear part of the prosthesis liner, the sealing lip 26 can extend down again in the distal direction. Such a profile corresponds to the profile of the proximal edge of a lower leg socket, which extends deeper in the frontal tibial region and in the popliteal region, that is to say is oriented there more in the distal direction than in the medial-lateral direction. Medially and laterally of the knee joint, prosthesis socket regions can be arranged extending further in the proximal direction, in order to achieve increased lateral stability and an improved contact between the lower leg socket and the stump.

[0033] FIG. 2 shows a schematic view of the prosthesis liner 20 according to FIG. 1 in a fitted state. The prosthesis liner 20 is applied to the stump (not shown) and inserted into a prosthesis socket 10. The prosthesis socket 10 has a proximal edge 11, which does not lie in a flat plane but describes a three-dimensional curve. The prosthesis socket 10 has medially and laterally raised regions that extend further in the proximal direction than the regions that are arranged frontally and in the popliteal region. A cutout can be seen at the front that allows the kneecap to move. In the rear region of the hollow of the knee, a corresponding cutout or a corresponding depression is formed in order to allow the leg to bend without the dorsal region of the prosthesis socket being caught between the back of the thigh and the calf region.

[0034] The prosthesis liner 20 is fully inserted into a receiving space 15 of the prosthesis socket 10, that is to say the distal end 22 of the prosthesis liner 20 is located in the region of the distal end 12 of the prosthesis socket 10, optionally bearing thereon or spaced slightly apart therefrom, for example via padding. The sealing lip 26 bears on the inner wall of the prosthesis socket 10 and seals off a volume 30 between the inner wall of the prosthesis socket 10 and the outer wall 23 of the prosthesis liner 20 distally with respect to the sealing lip 26. The volume 30 is evacuated, for example by a pumping movement during walking, through an outlet valve or by a motor-driven pump, i.e. brought to a pressure level that is below the atmospheric pressure.

[0035] It will be seen from FIG. 2 that the sealing lip profile corresponds to or follows the profile of the proximal edge 11 of the prosthesis socket 10 and is located or arranged, only offset in the distal direction, on the outer face of the base body 25. The sealing lip 26 ideally extends as close as possible to the proximal edge 11 of the prosthesis socket 10. In particular, the height profile or the height contour, that is to say the profile of the sealing lip 26 around the circumference of the base body 25 in the proximal-distal direction, corresponds to the height profile of the proximal edge 11 of the prosthesis socket. Slight deviations may be possible; in particular, the sealing lip profile can be determined in a region that is substantially parallel to the profile of the height contour of the proximal edge 11 of the prosthesis socket 10, wherein the proximal and distal border of the region is designed corresponding to the height contour profile of the proximal edge 11.

[0036] The contour in the circumferential direction, i.e. the contour of the inner circumference of the prosthesis socket 10 in the region of contact with the sealing lip 26, can also be detected. The contour of the outer circumference of the sealing lip 26 can then be designed corresponding to the profile of the circumferential contour in the region of the contact of the outer sealing lip edge on the inner face of the prosthesis socket 10, provided with an add-on such that the sealing lip 26 can bear on the inner face of the prosthesis socket 10 with slight pre-tensioning due to the restoring forces in the event of a deformation after the prosthesis liner 20 has been inserted in the prosthesis socket 10.

[0037] As an alternative to an embodiment of the prosthesis socket 10 as a lower leg socket with elevations on the medial and lateral sides, it is possible, for example, that an embodiment as a thigh socket can have an elevation laterally on just one side, which reaches approximately as far as the axis of rotation of the hip joint. On the medial side of the thigh, a cutout that is offset in the distal direction is formed accordingly, resulting in a corresponding sealing lip profile in a thigh liner.

[0038] To produce such a liner 20, the height contour of the prosthesis socket 10, which is usually made on an individual basis, is detected first of all. For this purpose, the height of the prosthesis socket 10 is also detected, i.e. the distance from the proximal edge 11 to the distal end 12 on the inner face of the prosthesis socket 10 over the circumference of the stump. The shape and the dimensions can preferably be detected optically, for example by image recording and image evaluation; alternative detection data such as scanning with measurement value sensors can also be effected. If the prosthesis socket 10 for production was already digitally modeled, the height contour can be detected directly from the digital model and used as a reference for the sealing lip profile.

[0039] On the basis of the detected profile of the height contour of the proximal edge 11, it is then determined where the sealing lip 26 should bear on the inner face of the prosthesis socket and thus where the sealing lip is to be arranged on the outer face 23 of the base body 25 of the prosthesis liner 20. The detected data are used to create a 3D data model. Using the data model of the prosthesis socket 10, the liner 20 is constructed, for example with a standard base body 25 and an individual sealing lip profile of the sealing lip 26, which is adapted to the profile of the proximal edge 11 of the prosthesis socket 10. The shape of the prosthesis liner with the adapted sealing lip profile is likewise calculated as a 3D data model. The 3D data model is used to generate manufacturing data, which are then used to produce the prosthesis liner 20 using an additive manufacturing process, with the sealing lip profile corresponding to the profile of the proximal edge 11 of the prosthesis liner.

[0040] FIG. 3 shows a possible sequence of a method for producing a prosthesis liner 20. From a stump 2, in this case a stump of the lower leg, an optical detection device 3 is used to record, i.e. scan, the outer contour of the stump 2. From the stump 2, a 3D model is created and processed in a computer (not shown). A data set 20′, which substantially represents the shape of the subsequent prosthesis liner 20, is calculated on the basis of the 3D model. In addition to the sealing lip profile 26, the data set 20′ also establishes the outer contour of the prosthesis liner 20, especially also the distal end 22 and, if appropriate, the material thickness of the prosthesis liner 20. By way of the data set 20′, it is possible to define reinforcements, material weaknesses and the use of different materials, which are then used or incorporated during the manufacturing process. The actual prosthesis liner 20 can be manufactured on the basis of the data set 20′. In the exemplary embodiment, the proximal edge 21 or the profile of the proximal edge 21 of the actual prosthesis socket 20 is not yet fixed as in the data set 20′. The rest of the contour of the prosthesis liner 20 is indicated by the broken line. Based on the data set 20′ or on the basic data from the scan, a data set for the prosthesis socket can be created which forms the basis for the manufacture of the latter, for example in an additive manufacturing process. The sealing lip profile 26 is defined in space as a contour line and can serve as a reference for the profile of the contour of the proximal edge of the prosthesis socket. The sealing lip profile of the sealing lip 26 on the outer face of a prosthesis liner 20 that is yet to be manufactured can therefore be determined first, and the prosthesis socket is designed thereafter. Conversely, there is the possibility of adapting the sealing lip profile to an already determined contour of the proximal edge of a virtual or already existing prosthesis socket.

[0041] Based on the data set 20′, the prosthesis liner 20 is produced in an additive manufacturing process. In the exemplary embodiment shown, the production takes place according to what is called a rapid liquid printing process, in which a support material 5 is arranged in a tank or storage container 4. By way of a nozzle 6, which can be moved three-dimensionally in space, the material of the prosthesis liner 20 is introduced into the support material 5 and the prosthesis liner 20 is additively manufactured. The dashed line indicates the proximal end contour of the prosthesis liner 20, which is rectilinear in the exemplary embodiment shown. The proximal end contour or the proximal edge 21 of the prosthesis liner can also extend in a manner corresponding to the profile of the sealing lip 26 or corresponding to the proximal edge of the prosthesis socket.