SUPPORT STRUCTURE

Abstract

A support structure, a prosthesis component, and a method for producing a prosthesis component.

Claims

1-15. (canceled)

16. A support structure, comprising: at least one composite material, wherein the support structure is a shell-shaped body, 3D structure or free-form surface.

17. The support structure according to claim 16, wherein the composite material is selected from the group comprising carbon fibre-reinforced plastics material, glass fibre-reinforced plastics material, aramid fibre-reinforced plastics material, metal fibre-reinforced plastics material, ceramic fibre-reinforced plastics material, natural fibre-reinforced plastics material or mixtures of these.

18. A prosthesis component, comprising: a sheath and the support structure according to claim 16, wherein the support structure is attached to the shell on the inside and/or outside.

19. The prosthesis component according to claim 18, wherein the sheath is made of a plastics material, ceramic, metal or mixtures of these.

20. The prosthesis component according to claim 18, wherein the support structure has at least two mouldings.

21. The prosthesis component according to claim 20, wherein the mouldings of the support structure are connected to one another at a point, depending on the force load points.

22. The prosthesis component according to claim 21, wherein the sheath and support structure are non-positively and/or positively and/or materially connected to one another at this point.

23. The prosthesis component according to claim 22, wherein, in the case of a non-positive and/or positive and/or material connection of the sheath and support structure, a fastener is selected from the group comprising screws or rivets for non-positive connections, and/or from the group comprising adhesives for material connections, and/or clamps for positive connections.

24. A method for producing a prosthesis component according to claim 18, comprising the following steps: a) moulding the sheath by additive manufacturing, injection moulding or casting, b) pretreating the surface of the sheath, c) forming the support structure on the sheath surface pretreated in step b), wherein at least two layers each consisting of at least one composite material portion are applied, d) curing the support structure according to step c) at temperatures in a range from 80 to 150° C. and a pressure of 1 to 10 bar for 3 to 240 min, e) separating the sheath and support structure, f) post-processing the support structure, g) bringing the sheath and support structure together, h) connecting the sheath and support structure by a fastener in a non-positive and/or positive and/or materially-bonded manner.

25. The method according to claim 24, wherein the sheath in step a) is formed from a plastics material, ceramic or metal.

26. The method according to claim 25, wherein the sheath in step a) is made of a plastics material from the group comprising thermoplastics, elastomers or duromers.

27. The method according to claim 24, wherein in step a), when the sheath is moulded, and in step c) when the support structure is formed, the calculated thermal distortion during curing of the prosthesis component made of the sheath and support structure is taken into account, so that steps b) and e) - g) are omitted.

28. The method according to claim 24, wherein, in step a), the sheath is adapted on the inside according to the determined individual shape of the amputation stump, and the outer contour corresponds to a standard shape, and the support structure in step c) is formed on a separate tool, wherein at least two layers each consisting of at least one composite fibre material portion are applied, such that the steps b) and e) are omitted.

29. The method according to claim 24, wherein, in the case of a non-positive and/or positive and/or material connection of the sheath and support structure, the fastener is selected from the group comprising screws or rivets for non-positive connections, and/or from the group comprising adhesives for material connections, and/or clamps for positive connections.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0038] In the following, purely by way of example, the present invention is described by way of advantageous embodiments and with reference to the accompanying drawings.

[0039] FIG. 1a is a perspective view of a sheath (1) and a support structure (3).

[0040] FIG. 1b is a perspective view of a prosthesis component comprising a sheath (1) and a support structure (3).

[0041] FIG. 2 is a cross section of a prosthesis component comprising a sheath (1) having standardised support structures (3), (3′) and (3″).

[0042] FIG. 3 is a perspective view of a sheath (1) and sheath (1′).

DETAILED DESCRIPTION

[0043] FIG. 1a shows a sheath (1) and a support structure (3) having mouldings (7).

[0044] FIG. 1b shows a prosthesis component comprising a sheath (1) and a support structure (3) having mouldings (7).

[0045] FIG. 2 shows a prosthesis component comprising a sheath (1) having standardised support structures (3), (3′) and (3″). Which of the standardised support structures (3), (3′) and (3″) is used for the prosthesis component depends on the size of the sheath (1), which is adapted to the amputation stump. In this case, it is the standardised support structure (3). The standardised support structures (3′) and (3″) are shown in this case only for the sake of clarity. The standardised support structure (3) is selected because the smallest thickening (8) is necessary compared to standardised support structures (3′) and (3″).

[0046] FIG. 3 is a perspective view of a sheath (1) and a sheath (1′). The sheath (1) represents the final sheath. The sheath (1′) contains, for example, the thermal distortion calculated for the sheath (1), so that the sheath (1) is obtained after the hardening of the support structure (not shown) with the sheath (1′).

[0047] The present invention is explained below using embodiments which, however, do not represent any limitation of the invention.

[0048] A prosthesis component can be produced as described below.

Embodiment 1

[0049] The patient’s amputation stump was scanned and processed digitally, with the appropriate software being used to generate the geometry of the sheath (1) to be printed for the prosthesis component, and also the shape and thickness of the required support structure. Based on this model, a personalised sheath (1) made of a plastics material (polyamide 12) was produced using a 3D printing process. In the further process, this sheath (1) also served as a tool for the production of the support structure (3). For this purpose, the sheath (1) was covered with a 0.1 mm thick PVA (polyvinyl alcohol) film (separating layer) (2) without any creases. To produce the support structure (3), the support structure was laid in layers at the calculated points using an automated placement method, by alternating the arrangement of four composite material portions (4) (uncured composite material on a duromer epoxy resin basis with endless carbon fibres with a length of 55 mm) in 0/90° and +45/-45° orientation. In the next step, composite material portions were cured to form the support structure. For this purpose, the sheath (1) with the separating layer (2) applied and the composite material portions (4) laid down to form the support structure were cured in an autoclave process with a heating ramp of 2 K/min at 110° C., at a pressure of 6 bar, for a holding period of two hours. The resulting support structure (3a) was then separated from the sheath (1) by using the separating layer (2). Based on the data from the digital model, the edge contour and the surface of the support structure (3a) were then processed using a milling procedure, resulting in the support structure (3b). This was sealed with a varnish before the support structure (3) was connected to the sheath (1) in the subsequent step. For this purpose, a thixotropic 2-component PUR adhesive (5) was applied to the support structure (3) as a fastening means, the support structure (3) was connected to the sheath (1) and cured under mechanical contact pressure for 24 hours, so that a materially-bonded prosthesis component was obtained.

Embodiment 2

[0050] The patient’s amputation stump was scanned and processed digitally using software to determine the geometry of the required sheath (1) as an individual prosthesis component, and the shape and thickness of a required support structure (3). In order to manufacture the support structure (3) directly on the sheath (1), the expected thermal distortion was determined using an FEM model and included in the design of the sheath and support structure in such a way that the components could be produced in a way that deviates from the shape determined by scanning; and the distortion was used to bring the combination of support structure and sheath into the final desired shape. The model of the sheath (1′) determined in this way was produced from a plastics material (polyamide 12) using a 3D printing process. To produce the support structure (3), the support structure was laid in layers on the sheath (1′) at the calculated points using an automated placement method, by alternating the arrangement of four composite material portions (4) (uncured composite material on a duromer epoxy resin basis with endless carbon fibres with a length of 55 mm) in 0/90° and +45/-45° orientation. In the next step, composite material portions were cured to form the support structure (3). For this purpose, the sheath (1′) with the pre-cut parts (4) laid to form the support structure was cured in an autoclave process with a heating ramp of 2 K/min at 110° C., at a pressure of 6 bar, for a holding period of two hours. Due to the direct contact of the two materials, the sheath (1′) and the pre-cut parts (4) laid to form the support structure, the material is distorted to produced the desired final geometry simultaneously with the adhesion between the support structure and the shell due to the adhesive properties and the penetration of the resin into the shell material during curing. For aesthetic reasons, the prosthesis component was painted with a varnish. An individually adapted and materially-bonded prosthesis component consisting of a sheath (1) and a support structure (3) was thus produced.

Embodiment 3

[0051] The patient’s amputation stump was scanned and processed digitally, with the appropriate software being used to generate the geometry of the sheath (1) to be printed for the prosthesis component, and also the shape and thickness of the required support structure (3). The inner contour of this sheath (1) had a precisely fitting surface for the scanned amputation stump, but was adapted on the outside by a thickening (8) so that this outside corresponds to a previously defined standard shape. Based on this model, a sheath (1) was made from a plastics material (polyamide 12) using a 3D printing process. A plurality of models of the standard shape of the outer contour mentioned were defined independently of the scan mentioned. This standard shape could be used as a tool (6) on which the support structure (3) required for the sheath (1) was manufactured. The tool (6) was prepared in advance using a release agent (semi-permanent polymer resin) in order to ensure subsequent detachment of the support structure (3) from the tool (6). To produce the support structure (3), the support structure was laid in layers on the prepared tool in a targeted manner using an automated manufacturing process, by alternating the arrangement of four composite material portions (4) (uncured composite material on a duromer epoxy resin basis with endless carbon fibres with a length of 55 mm) in 0/90° and +45/-45° orientation. In the next step, composite material portions were cured to form the support structure (3). For this purpose, the tool (6) with the composite material portions (4) laid to form the support structure was cured in an autoclave process with a heating ramp of 2 K/min at 110° C., at a pressure of 6 bar, for a holding period of two hours. The resulting support structure (3a) was then separated from the tool (6) provided with a release agent. Then, based on the data from the digital model, the edge contour and the surface of the support structure (3a) were processed using a milling process, resulting in the final support structure (3). A thixotropic 2-component PUR adhesive (5) was applied to the support structure (3) as a fastening means, the support structure (3) was connected to the sheath (1) and cured under mechanical contact pressure for 24 hours, so that a prosthesis component was obtained.

TABLE-US-00001 List of reference signs 1, 1′ sheath 2 separating layer 3, 3′, 3″ support structure 3a support structure before processing 3b support structure after processing 4 composite material portions 5 adhesive 6 tool 7 mouldings 8 thickening