Abstract
A method for making a mould of an amputation stump, in which the amputation stump is inserted into a liner of a moulding aid, the liner having a longitudinal direction and a circumference, and the liner having an expansion coupling such that when the liner is extended in the longitudinal direction, this necessarily results in a reduction of the circumference.
Claims
1. A method for making a mold of an amputation stump, the method comprising: inserting the amputation stump into a liner of a molding aid, the liner having a longitudinal direction, a circumference, and an expansion coupling; lengthening the liner along the longitudinal direction to reduce the circumference, wherein the amputation stump is measured optically after insertion into the liner.
2. The method as claimed in claim 1, wherein the amputation stump, after insertion into the liner, is loaded by the patient.
3. The method as claimed in claim 1, wherein the amputation stump, prior to insertion into the liner, is equipped with a molding material and a release layer.
4. (canceled)
5. The method as claimed in claim 3, wherein after insertion of the amputation stump into the liner, the amputation stump and the molding material is shaped.
6. A molding aid for use with a method for making a mold of an amputation stump, the molding aid comprising: a liner for receiving an amputation stump, the liner having a longitudinal direction, a circumference, and an expansion coupling, the liner configured to reduce its circumference upon lengthening of the liner in the longitudinal direction; and a laser measuring device for optically measuring the amputation stump after insertion of the amputation stump into the liner.
7. The molding aid as claimed in claim 6, wherein the liner has or is made of a braided tube or a net of intersecting fibers, wherein the fibers, in an unloaded state, enclose an angle of 45° with the longitudinal direction of the liner.
8. The molding aid as claimed in claim 6, wherein the liner is held in a retaining device.
9. The molding aid as claimed in claim 8, wherein the retaining device is adjustable in height.
10. The molding aid as claimed in claim 9, wherein the liner is deflected around a ring and guided back onto itself, and wherein the ring with the liner comes to bear on the retaining device.
11. The molding aid as claimed in claim 8, wherein the retaining device is exchangeable or expandable.
12. The molding aid as claimed in claim 8, wherein the retaining device is secured on a support device.
13. The molding aid as claimed in claim 12, wherein the retaining device is arranged foldably on the support device, and in one position engages in latching elements or is clamped or wedged onto the support device.
14. A method for making a mold of an amputation stump, the method comprising: inserting the amputation stump into a liner of a molding aid, the liner having a longitudinal direction, a circumference, and an expansion coupling; lengthening the liner in the longitudinal direction to reduce the circumference, the lengthened liner providing the mold of the amputation stump; and optically measuring the amputation stump after insertion into the liner.
15. The method as claimed in claim 14, further comprising loading the amputation stump by the patient after insertion of the amputation stump into the liner.
16. The method as claimed in claim 14, further comprising, prior to insertion of the amputation stump into the liner, equipping the amputation stump with a molding material and a release layer.
17. The method as claimed in claim 16, further comprising shaping at least one of the amputation stump and the molding material, after insertion of the amputation stump into the liner.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Illustrative embodiments of the present invention are explained in more detail below with reference to the attached drawings, in which:
[0034] FIGS. 1a and 1b show schematic views of a liner and of an amputation stump before and after insertion;
[0035] FIGS. 2a and 2b show schematic drawings illustrating the way in which the liner is secured;
[0036] FIG. 3 shows the schematic view of a molding aid with the amputation stump inserted;
[0037] FIG. 4 shows the schematic view of a molding aid in the transport position;
[0038] FIGS. 5 to 8 show various stages of a molding method according to an illustrative embodiment of the present invention, and
[0039] FIGS. 9 and 10 show two depictions of different stages of a method according to a further illustrative embodiment of the present invention.
DETAILED DESCRIPTION
[0040] FIG. 1 shows schematically the function of the coupling of longitudinal and transverse expansion in the liner (2), while the prosthetic stump is being received. The prosthetic stump is secured on the securing ring (3) and, as is indicated in the surface texture, is made of a net or braid with diagonally extending fiber orientation. By longitudinal deformation of the liner, there is an increased orientation of the fibers in the longitudinal direction, which at the same time reduces the circumference of the liner. The deformation of the liner ceases when the stump (1) is completely enclosed. When the stump is subjected to a load, a uniform pressure is exerted on the stump. The liner consists of a braided tube of yarn or monofilaments or of a net of tubular shape with a diagonal profile of the filaments or with a hexagonal structure. Braided tubes made of polyamide or polypropylene monofilaments are particularly advantageous, since these are very movable and yet form a closed surface. The size is chosen such that the stump is completely enclosed when the filaments of the braided tube have an intersection angle of approximately 90° or when the hexagonal structure is undistorted. At the distal end, the tube can be bound together or adhesively bonded or welded to a flexible closure cap (9). In any case, it is recommended to generate a smooth surface internally at the distal end by means of an elastic plate being bonded in or by means of the distal end being cast with elastomer. At the proximal end, the liner is connected to the securing ring (3).
[0041] FIG. 2 shows a cross-sectional view of an advantageous securing of the liner on the securing ring (3). The securing ring (3) can have a stepped configuration in order to provide centering for the ring (4). The liner (2) is folded about the ring (4) and guided back onto itself within the securing ring (3). When the liner is subjected to a load, as shown in FIG. 2B, the multiple deflection results in the ring (4) being pressed firmly onto the securing ring (3), consequently with high frictional forces which hold the liner safely in the securing ring as long as it is loaded. An advantage of this arrangement is that the liner can be oriented inside the ring according to the position of the lower limb. Ideally, the liner is fitted by being held taut on the stump, when the folded-down end is pulled, and then being subjected to a load by the user.
[0042] FIG. 3 shows a possible embodiment of the whole molding aid. The liner (2) receives the stump (1). Its proximal end is held in the securing ring (3). The latter is secured on the column (5) by means of a clip (7). The axle (10) allows the securing ring (3) to be folded up onto the column. When folded down, the configuration creates an abutment which holds the securing ring in a horizontal position. At the same time, when the securing ring is loaded from above, strong forces act on the column and prevent the clip from slipping along the column. In this way, the securing ring (3) is steplessly adjustable in height, without a lock having to be released for this purpose.
[0043] The column (5) is secured on the base plate (6) by means of a hinge. In the vertical position of the column, the position of the rotation point of the hinge creates an abutment, which is stabilized by the securing ring (3) being loaded from above. It is thus possible for the molding aid to be used without danger of the column pivoting rearward.
[0044] FIG. 4 shows the molding aid from FIG. 3 in the folded-up state. The column (5) is here pivoted onto the underside of the base plate (6). The securing ring (3) is folded against the column (5). It can be seen that the molding aid is very compact in this state and can be easily transported and stowed. Its erection requires few maneuvers.
[0045] FIG. 5 shows how the amputation stump 1, which in the illustrative embodiment shown is equipped with a modeling layer of plaster 11 and a release film, is inserted into the liner 2. A distal edge 12 of the liner 2 is turned back. The individual fibers, through which the coupling between longitudinal expansion and circumferential reduction is obtained in the illustrated liner 2, are not shown in FIGS. 5 to 10.
[0046] The following is shown in FIG. 6. The patient 13 stands on his intact leg, and the stump 1 with the liner 2 is inserted into the securing ring 3 and is held there. The patient 13 can now exert a load on the amputation stump 1 and thereby ensures that the liner 2 is lengthened in the longitudinal direction, i.e. from the top downward in FIG. 6. By means of the coupling between longitudinal expansion and transverse expansion, this necessarily leads to a reduction of the circumference and therefore to a force that acts on the amputation stump 1 and is directed radially inward.
[0047] The situation from FIG. 6 is again shown in FIG. 7, where a further person, for example a prosthetist 14, is now able to shape the amputation stump 1 in the liner 2 while the amputation stump 1 is held in the securing ring 3. In this way, the layer of plaster 11, which is located inside the liner 2, can be modeled and, if appropriate, shaped or reshaped. In this way, account can be taken of the individual circumstances presented by the amputation stump 1.
[0048] FIG. 8 shows the concluding phase, in which the patient 13 stands on his intact leg and exerts a load on the amputation stump 1 inside the securing ring 3. In this way, the already described force is applied by the liner 2 to the amputation stump and the molding material of plaster 11 which is located inside the liner, until the material is sufficiently hardened to remove the liner from the securing ring 3.
[0049] FIG. 9 shows the situation in a method according to a further illustrative embodiment of the present invention. The patient 13 again stands on his intact leg, and the amputation stump 1 is inserted into the liner 2. However, in contrast to FIGS. 5 to 8, there is no plaster 11 arranged inside the liner between the liner 2 and the amputation stump 1. The liner is again held in the securing ring 3, but it now has markings 15 which permit an optical measurement.
[0050] This optical measurement is shown in FIG. 10. The amputation stump 1 of the patient 13 is located in the liner 2, which has the configuration shown in FIG. 9. By means of a laser measurement device 16, as is known in principle from the prior art, the geometric shape of the liner 2 in which the amputation stump 1 is located is now measured three-dimensionally. The data thus determined can be used to produce the prosthesis socket. The securing ring 3 is arranged on the column 5 and is preferably adjustable in height, i.e. displaceable in particular along the longitudinal direction of the column. In a particularly preferred embodiment, the securing ring 3 is additionally pivotable toward the column 5 in order to be able to bring the molding aid to the transport position shown in FIG. 5. For this purpose, it is advantageous if the base plate 6 is also pivotable relative to the column 5.
