Method and device for producing a prosthesis for a body part of a limb

Abstract

The invention relates to a method and a device (100) for producing a prosthesis (10) for a body part of a limb. According to the invention, a digital image is created of each of an impaired body part (20) of a limb and an associated unimpaired body part of the limb. Based on the digital image of the impaired body part (20) and the mirrored digital image of the unimpaired body part, a digital image is created of a prosthesis (22) for the impaired body part. Therefore, the prosthesis (10) does not have to be designed from scratch; instead, it can be based on the shape of the unimpaired body part owing to the chirality of limbs. At least one prosthesis (10) is subsequently produced for the impaired body part using the digital image of the prosthesis (22) and a 3D printer (106) with a print resolution of less than 0.1 mm.

Description

[0001] Description

[0002] Method and device for producing a prosthesis for a body part of a limb

[0003] The invention relates to a method and a device for producing a prosthesis for a body part, such as a limb. In humans and animals, a limb is defined as a pair of body appendages that are moved by muscles. Examples include fingers, hands, arms, legs, feet, and the like.

[0004] Prostheses are used to replace or complete missing or limited body parts. As is well known, a rough prosthetic blank is first created, which is then successively and individually adjusted by an orthotist to the shape and form of the affected body part. The patient often visits the orthotist several times to fine-tune the custom-made prosthesis. In particular, to produce lifelike prostheses, fine surface structures must be incorporated into the individual prosthesis by hand. Accordingly, the time required to produce a custom prosthesis is high, which means that lifelike prostheses are not affordable for everyone. If the custom-made prosthesis is damaged or lost, the complex manufacturing process must be repeated from scratch.

[0005] Therefore, it would be desirable to simplify the production of lifelike prostheses.

[0006] The invention is therefore based on the object of providing a device and a method for the simplified and cost-effective production of individual prostheses.

[0007] The object of the invention is achieved by a method and a device for producing a prosthesis for a body part of a limb according to the independent patent claims. Preferred developments are the subject of the respective dependent claims.

[0008] A first aspect relates to a method for producing a prosthesis for a body part of a limb. In one method step, a digital image of an impaired body part of a limb and a digital image of a corresponding intact body part of the limb are created. An impaired body part is, for example, a completely or partially missing or damaged body part. In other words, the digital images correspond to a digital model or copy of the physical body parts. The digital images are preferably created as high-density meshes using a 3D scanner and / or an imaging method such as computed tomography (CT), digital volume tomography (DVT), and the like. The quality of the digital images is preferably such that fine surface structures of the body parts are included.Fine surface structures are, for example, structures that can be distinguished in width and / or depth at a resolution below 0.1 mm, for example from 0.09 mm to 0.01 mm, preferably from 0.05 mm.

[0009] In a further method step, a digital image of a prosthesis for the impaired body part is created using a mirrored digital image of the intact body part and the digital image of the impaired body part. Because body parts of limbs occur in pairs and are almost identical in their mirror image (chirality), the mirrored shape of the intact body part is used to design the prosthesis for the impaired body part. Complex design and adaptation steps for the prosthesis from a blank are not required. Furthermore, a customized prosthesis is created that mimics the patient's own body, which can provide psychological support for the patient, especially in the case of a recent (partial) amputation of the body part.

[0010] In the simplest case, the mirrored digital image of the intact body part can be reduced by the shape of the digital image of the impaired body part, so that the remaining part represents the image of the prosthesis for the impaired body part. This is preferably done using 3D editing software, for example a slicer program such as Geomagic® Freeform® or Blender. Further aesthetic and / or functional adaptation steps are also preferably carried out using 3D editing software. For example, the digital image of the impaired body part is slightly scaled down to ensure a tight and secure fit of a (subsequent) prosthesis. Furthermore, the transition between the digital image of the prosthesis and the digital image of the impaired body part is preferably adjusted and / or a wall thickness of the digital image of the prosthesis is standardized.In a further process step, at least one prosthesis for the affected body part is produced using the digital image of the prosthesis and a 3D printer with a print resolution of less than 0.1 mm. Preferably, a 3D printer with a print resolution of less than 0.09 mm, less than 0.08 mm, less than 0.07 mm, less than 0.06 mm, or less than 0.05 mm is used. The print resolution preferably refers to a direction along the height direction of the layer thickness of the material used. By limiting the print resolution to a range of less than 0.1 mm, the surfaces of the prosthesis are significantly smoother than with other additive manufacturing processes, such as FDM printers (Fused Deposition Modeling - FDM) or FFF printers (Fused Filament Fabrication - FFF), which, for example, enable a print resolution of 0.2 mm to 0.15 mm.Consequently, a particularly lifelike prosthesis is provided that provides a high level of comfort and an improved wearing experience for the user. To enable even smoother prosthetic surfaces, a 3D printer with a print resolution of less than 0.04 mm, less than 0.03 mm, less than 0.025 mm, or less than 0.02 mm is particularly preferred.

[0011] According to the present invention, a lifelike prosthesis for a body part of a limb can be manufactured quickly and easily. By having a digital image of the prosthesis, a large number of prostheses can be manufactured or reproduced without great effort. This is possible in the long term and cost-effectively. Even if the affected body part changes over time, a change in the body part can be responded to quickly and easily by adapting the digital image of the prosthesis, for example, using a newly created digital image of the affected body part. Furthermore, the color of the prostheses can be adapted or varied, for example, to offer a selection of different colored prostheses. This makes it possible to take into account, in particular, seasonal changes in the patient's skin tone.

[0012] In a preferred embodiment, the prosthesis for the impaired body part is printed directly from the digital image of the prosthesis using the resin 3D printer. Direct printing of the prosthesis represents a simple and rapid method for physically producing the prosthesis according to its digital image.

[0013] In a further preferred embodiment, a positive mold of the prosthesis and a positive mold of the impaired body part are created using the digital images of the prosthesis and the impaired body part and using the synthetic resin 3D printer. Furthermore, a negative impression of the prosthesis is created using the positive mold of the prosthesis, and the prosthesis for the impaired body part is manufactured using the negative impression of the prosthesis. In other words, the prosthesis for the impaired body part is printed indirectly from the digital image of the prosthesis using the synthetic resin 3D printer. By creating a negative impression of the prosthesis, the color variety can be increased and the costs of manufacturing the prosthesis or a plurality of prostheses can be reduced, since the manufactured prosthesis is not dependent on the colors predetermined by the synthetic resins of the 3D printer.As a result, cheaper materials can be used to manufacture the prosthesis compared to synthetic resin. Silicone rubber is the preferred material.

[0014] Silicone rubbers are particularly skin-friendly, easy to process, and inexpensive. Silicone is preferably poured into the negative impression of the prosthesis, and the positive mold of the affected body part is inserted or pressed into the negative impression of the prosthesis to create a precise transition from the prosthesis to the affected body part in the negative impression. The negative impression can be reused multiple times, making it easy to produce a variety of prostheses. By coloring the silicone accordingly, a wide variety of skin tones can be covered. Changes to the affected body part can be addressed analogously by updating the digital image of the affected body part and printing it as a new positive mold of the affected body part using a 3D printer.By pressing the new positive mold into the silicone in the negative impression, the prosthesis can be designed with an adapted new transition to the affected body part.

[0015] Preference is given to using cold-curing (room temperature curing - RTV) and / or hot-curing (high temperature curing - HTV) silicone rubbers and / or liquid silicone rubbers (LSR). The Shore hardness of the cured silicones is preferably A 30 to A 80, preferably A 30 to A 60, and particularly preferably A 50, measured according to DIN ISO 48-4. Examples of RTV silicones are REPISIL 35 NO A / B with a Shore hardness of A 35 (according to DIN ISO 868) and SF 45 - RTV 2 with a Shore hardness of A 45 (according to DIN ISO 48-4). An example of a liquid silicone is ELASTOSIL® KR 5040 / 50 A / B with a Shore hardness of A 50 (according to DIN ISO 48-4).

[0016] When manufacturing the prosthesis for the affected body part, a textile fabric is preferably embedded into the resulting prosthesis. The embedded textile fabric serves to reinforce the silicone and increase its tear resistance. This also allows the silicone wall thickness to be reduced, thus saving material costs and reducing the weight of the prosthesis. Preferably, a textile stocking is clamped into the negative impression of the prosthesis, and the silicone is poured into the negative impression of the prosthesis. Pressing in the positive mold of the affected body part ensures that the silicone envelops the stocking. Nylon stockings are preferred. Nylon is particularly tear-resistant.

[0017] Also preferably, air holes and / or molded locks are inserted into the digital images of the affected body part and the prosthesis. The air holes (also called air channels) allow for better ventilation of the silicone in the negative impression of the prosthesis. The application of molded locks ensures the correct fit of the positive mold of the affected body part in the negative impression of the prosthesis, thus simplifying manufacturing. The molded locks are preferably designed in such a way that only one possible arrangement is possible.

[0018] In a further preferred embodiment, the prosthesis for the impaired body part comprises a relief cushion made of a soft silicone and / or a soft 3D-printed synthetic resin. The digital image of the impaired body part (20) is preferably extended by a predetermined thickness of the relief cushion and / or the digital image of the prosthesis is preferably supplemented by a relief area provided for the relief cushion. The relief cushion serves as a buffer between the prosthesis and the body part, thereby improving the patient's wearing comfort and feeling. In other words, the introduction of the relief cushion into the prosthesis to be manufactured is planned before its manufacture by appropriately editing the digital image of the prosthesis for the impaired body part or the digital image of the impaired body part.This greatly simplifies the production of a prosthesis with a relief cushion. Preferably, the prosthesis for the affected body part and the relief cushion are formed as a single piece. This improves the longevity and durability of the prosthesis. The term "single piece" refers to the fact that no additional material is required to (subsequently) connect the prosthesis to the relief cushion, i.e., a binder, adhesive, fastening element, or the like. The soft silicone and / or the soft 3D-printed synthetic resin preferably has a Shore hardness of 00-10 to A 30, preferably 00-20 to A 5, particularly preferably 00-30 to 00-50 or 00-20 to 00-30, measured according to DIN ISO 48-4. Examples of soft silicones are the addition-curing silicones of the ECOFLEX® series.A soft 3D-printed resin is obtained, for example, by reducing the intended material density of the resin used in the relief area. For example, the number (and thus the density) of the 3D printing dots can be reduced and / or inclusions, i.e., cavities, can be provided in the 3D-printed resin in the relief area. Additionally or alternatively, another (different) 3D-printable resin can be used to form the relief cushion in the relief area, with the additional resin being softer than the resin used for the rest of the prosthesis.

[0019] Preferably, the digital image of the affected body part is extended by a predetermined thickness of the relief cushion. When manufacturing the prosthesis for the affected body part using the negative impression of the prosthesis, a first silicone is poured into the negative impression, the positive mold of the extended affected body part is pressed into the negative impression, and after the first silicone has cured, a second silicone is poured onto the first silicone in the negative impression. The second silicone is softer than the first silicone. This enables simple production of a prosthesis with a one-piece relief cushion. The one-piece design is achieved in that the second silicone adheres to the first cured silicone during crosslinking (due to the process). The first silicone is preferably the silicone mentioned above, while the second silicone is preferably the silicone referred to as soft.Preferably, the prosthesis for the affected body part is printed from the digital image of the prosthesis by the 3D printer, and the softness of the 3D-printed synthetic resin in the relief area is achieved by reducing the material density of the synthetic resin and / or by using an additional 3D-printed synthetic resin, wherein the additional synthetic resin is softer than the synthetic resin used for the rest of the prosthesis. The reduction in material density causes the printed synthetic resin to be more elastic and thus softer. Preferably, the reduced material density is incorporated into the digital image of the prosthesis before 3D printing, so that it is created directly during printing. This enables simple production of a 3D-printed prosthesis with a one-piece relief cushion.The one-piece design is achieved in that the additional resin is printed onto the resin used for the rest of the prosthesis during 3D printing and thus adheres to the remaining resin (due to the process).

[0020] In a further preferred embodiment, the color tone of the limb is determined, and the prosthesis is manufactured in a color based on the determined color tone. Preferably, a color scanner system is used to determine the skin tone. Examples of this are portable color sensors from Spectromatch or Nix Pro. Additionally or alternatively, reference photos of the limbs can be used. By determining the color tone of the limb, a prosthesis can be manufactured that comes as close as possible to the patient's skin tone, thus achieving a lifelike design. This can improve patient acceptance and thus the comfort of wearing the prosthesis. Preferably, the external appearance of the more intact body part is imitated by applying color to the prosthesis. This can be done using an airbrush, brush, or the like.

[0021] In a further preferred embodiment, the 3D printer used is an SLS or resin 3D printer. SLS (Selective Laser Sintering) 3D printers are characterized by high resolution and layer transitions that are essentially invisible (to the human eye), i.e., no individual visible layers. When using the SLS 3D printer, a layer of fine-grained powder is fed into the printer and fused into a single part by a laser. Resin 3D printers are characterized by their exceptional print quality. Resin 3D printers use 3D printing processes such as stereolithography (SLA) or digital light processing (DLP), whereby the resolution is determined by the optical point of the laser or projector (SLA) or the pixel (DLP).Because light is used for polymerization, no force is applied during printing, resulting in significantly smoother surfaces than with other additive manufacturing processes, such as FDM (Fused Deposition Modeling - FDM) or FFF (Fused Filament Fabrication - FFF) printers. In particular, layer thicknesses, i.e., a print resolution, of less than 0.08 mm, for example, from 0.04 mm to 0.08 mm, can be achieved with SLS 3D printers, and layer thicknesses, i.e., a print resolution, of less than 0.025 mm, for example, between 0.025 mm and 0.01 mm, can be achieved with resin 3D printers. In another embodiment, a 3D printer based on dual-color photoinitiators is preferably used.In this case, a material containing two-color photoinitiators is illuminated from different directions with light of different wavelengths corresponding to the absorption colors of the photoinitiators. Where the light of the different wavelength hits a two-color photoinitiator, selective materialization occurs so that a 3D model to be created can be generated using cross-sectional images obtained from the model.

[0022] In a further preferred embodiment, the size of the digital image of the prosthesis and / or the digital image of the affected body part is adjusted such that the produced prosthesis can be attached to the affected body part by means of a suction effect. For example, the size of one of the digital images is adjusted by 90 percent to 110 percent, preferably by 92 percent to 108 percent. Particularly for smaller limbs, such as fingers, this ensures sufficient hold, eliminating the need for additional fastening means. For larger limbs, fastening devices known to those skilled in the art, such as tabs, locking elements, and the like, can be provided.

[0023] In a further preferred embodiment, a negative impression of the affected body part and a negative impression of the corresponding intact body part are created. Furthermore, a positive mold of the affected body part and a positive mold of the intact body part are created using the negative impressions. The digital images of the affected body part and the intact body part are created using the positive molds. Using negative impressions, fine surface structures can be transferred to the positive molds.

[0024] This requires only the creation of negative impressions of the patient, which then enable the location-independent creation of digital images. For example, the patient's negative impressions are created and sent to another location for use there according to the invention. Consequently, the patient does not need to be present to create the digital images. Furthermore, there is no blurring caused by patient movement during the creation of the digital images. The negative impressions are preferably created using silicone, alginate, or plaster. The positive molds are preferably cast using plaster, polyurethane (PU), polymer plaster, or a similar material using the negative impressions.

[0025] In a further preferred embodiment, the manufactured prosthesis comprises a core made of a silicone mixture with fillers. Using a core with fillers, 25 percent to 33 percent of the weight of the prosthesis can be saved. The wall thickness of the outer layer of the prosthesis is then preferably between 0.5 cm and 1 cm. Cores made of silicone mixtures with fillers can be used particularly advantageously for foot prostheses, particularly forefoot prostheses. For a forefoot prosthesis for an adult, for example, a weight saving of approximately 400 g can be achieved.

[0026] In a further preferred embodiment, the digital image of the prosthesis includes a recessed area for an object to be inserted. For example, a fingernail or toenail is removed in the digital image so that the manufactured prosthesis has sufficient space to attach an artificial fingernail or toenail. Acrylic nails are preferably used. By attaching objects such as toenails or fingernails, the prosthesis becomes even more lifelike, thereby increasing wearer comfort. Additionally or alternatively, aesthetic defects can also be removed.

[0027] Another aspect relates to a device for producing a prosthesis for a body part of a limb. The device comprises a capture unit configured to create digital images of impaired and intact body parts of a limb. The capture unit is preferably a 3D scanner configured to create high-density meshes.The device further comprises an electronic control unit configured to create a digital image of a prosthesis for the impaired body part using a mirrored digital image of the intact body part and the digital image of the impaired body part, and a synthetic resin 3D printer configured to produce a prosthesis for the impaired body part using the digital image of the prosthesis and / or positive molds of the digital images of the prosthesis and the impaired body part using the digital images of the prosthesis and the impaired body part. The optional features described with the methods and their advantages can be implemented analogously with the device and can therefore be combined with one another as desired.

[0028] In a preferred embodiment, the device further comprises a mold kit for producing negative impressions.

[0029] The above-mentioned control unit is preferably implemented by electrical or electronic components (hardware) or by firmware (ASIC). Additionally or alternatively, the functionality of the control unit is realized by executing a suitable program (software). Likewise, the control unit is preferably implemented by a combination of hardware, firmware, and / or software. For example, individual components of the control unit are designed as separate integrated circuits or arranged on a common integrated circuit to provide individual functionalities.

[0030] The individual components of the control unit are further preferably embodied as one or more processes that run on one or more processors in one or more electronic computing devices and are generated when executing one or more computer programs. The instructions of the computer programs are preferably stored in a memory, such as a RAM element. However, the computer programs can also be stored on a non-volatile storage medium, such as a CD-ROM, a flash memory, or the like.

[0031] It will also be apparent to the person skilled in the art that the functionalities of several computing units (data processing devices) can be combined or combined in a single device or that the functionality of a particular data processing device can be distributed across a plurality of devices in order to implement the functionality of the control unit.

[0032] A further aspect relates to a computer program comprising instructions which, when the program is executed by a computer, such as a device for producing a prosthesis for a body part of a limb, cause the computer to carry out the method according to the invention, in particular a method for producing a prosthesis for a body part of a limb.

[0033] Further preferred embodiments of the invention emerge from the remaining features mentioned in the subclaims.

[0034] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual case.

[0035] The invention is explained below in exemplary embodiments with reference to the accompanying drawings. They show:

[0036] Figure 1 is a schematic representation of a method according to a

[0037] form of implementation;

[0038] Figure 2 is a schematic representation of a negative impression of an impaired

[0039] body part and a negative impression of an intact body part;

[0040] Figure 3 is a schematic representation of a positive form of an impaired

[0041] body part and a positive mold of the corresponding intact body part;

[0042] Figure 4 is a schematic representation of a digital image of the affected

[0043] body part and a digital image of the prosthesis; Figure 5 is a schematic representation of a positive form of the prosthesis and a

[0044] Positive shape of the affected body part;

[0045] Figure 6 is a schematic representation of a prosthesis for a body part of a

[0046] limb; and

[0047] Figure 7 is a schematic representation of a device according to a

[0048] Embodiment.

[0049] Figure 1 shows a schematic representation of a method sequence for producing a prosthesis 10 for a body part of a limb according to one embodiment. The method illustrated in Figure 1 is explained in more detail with reference to Figures 2 to 6 using a pair of fingers as body parts of a limb, without being limited thereto. Rather, it merely serves to illustrate the underlying inventive concept. The method allows for the simple and cost-effective production of individual prostheses 10.

[0050] In a first method step 50, a negative impression of an impaired body part 12 and a negative impression of the corresponding intact body part 14 are created (see Figure 2). For this purpose, silicone, alginate, or plaster is applied to the finger stump and the corresponding opposite intact finger of the patient, and the negative impressions 12, 14 are created. The negative impressions 12, 14 adopt the fine surface structures of the patient's two fingers. After the negative impressions 12, 14 have been created, the patient's presence is no longer required, so that the further production of the prosthesis 10 can take place without the patient. This minimizes the effort required by the patient. For example, the negative impressions 12, 14 taken from the patient can be sent to a specialized laboratory, for example, across borders, for further processing.

[0051] In a second method step 52, a positive mold of the affected body part 16 and a positive mold of the intact body part 18 are created using the negative impressions 12, 14 (see Figure 3). For this purpose, plaster, polyurethane (PU), or polymer plaster is pressed into the negative impressions 12, 14 so that the fine surface structures are transferred to the positive molds 16, 18. This preserves the information about the individual fingernail, the fingertip and knuckle shapes, and the characteristic skin and creases of the patient's finger. Since the positive molds 16, 18 serve as a physical copy of the patient's pair of fingers, preserving the characteristic design of the finger and the fine surface structures is important in order to be able to produce a prosthesis 10 that is as lifelike as possible.

[0052] Subsequently, a digital image of an impaired body part 20 of a limb (see Figure 4) and a digital image of a corresponding intact body part of the limb (not shown) are created (third method step 54). The digital images 20 are created using the positive molds 16, 18. High-density meshes of the two fingers are created using a 3D scanner or an imaging technique such as CT or DVT. The digital images 20 are created with such high detail that the characteristic configuration and the fine surface structures of the fingers are included. This allows structures down to 0.01 mm to be differentiated from one another, i.e., resolved.

[0053] In a fourth method step 56, a digital image of a prosthesis 22 for the impaired body part is created using a mirrored digital image of the intact body part and the digital image of the impaired body part 20 (see Figure 4 again). The invention exploits the fact that fingers occur in pairs in nature and the finger pairs are almost identical in their mirror image (chirality). Thus, a prosthesis for a finger stump, as chosen in the present example, can be manufactured based on the mirrored shape of the intact finger. Because the digital image of the intact finger is available, it can be digitally mirrored with ease. Consequently, an individual prosthesis is designed simply and cost-effectively, which mimics the patient's own body.The imitation of one's own body can provide psychological support for the patient, especially in cases of recent amputation or loss of a finger. Because the intact finger is digitally reproduced in such detail, the effect can be enhanced by a prosthesis manufactured with the same level of detail.

[0054] Since the digital images of both fingers are available in high resolution, the digital image of the prosthesis 22 can also be easily designed on the computer using a 3D editing program. To do this, the mirrored digital image of the intact finger is placed over the digital image of the finger stump 20, and the overlapping part is removed from the mirrored digital image of the intact finger. The remaining part of the digital image of the intact finger now forms the basis for the digital image of the prosthesis 22 for the finger stump. To ensure a better fit, the digital image of the finger stump 20 is slightly scaled down. Furthermore, a recessed area 28 is inserted into the finger as needed (see Figure 6) by exposing the nail bed of the finger in the digital image of the prosthesis 22 in order to glue an acrylic artificial nail onto it in the subsequent prosthesis 10.The artificial nail makes the prosthesis even more lifelike.

[0055] In a fifth method step 58, a positive mold of the prosthesis 24 and a positive mold of the impaired body part 26 are created using the digital images of the prosthesis 22 and the impaired body part 20 (see Figure 5). For this purpose, a 3D printer with a print resolution of less than 0.1 mm, such as a synthetic resin 3D printer, is used. Alternatively, an SLS 3D printer can also be used. It is important that the printer used can provide the required print resolution. In this respect, the 3D printer technology ultimately used is irrelevant. Only the print quality of the printer used, such as an SLS or synthetic resin 3D printer or a 3D printer with a comparable resolution, with which layer thicknesses between 0.1 and 0.01 mm are achievable, enables the fine surface structures of the digital images 20, 22 to be converted into the physical positive molds.

[0056] Based on the printed positive form of the prosthesis 24, a negative impression of the prosthesis is created in a sixth process step 60. The created negative impression of the prosthesis is now available for multiple use to produce a variety of prostheses 10, for example, from different materials and / or color mixtures. Compared to directly printing the prosthesis 10 with the 3D printer, the choice of material and color is not limited to the materials specified by the 3D printer, such as fine-grained powders or synthetic resins.

[0057] Consequently, cheaper materials, such as silicone rubber, can be used to manufacture the prosthesis 10. Silicone rubber is also skin-friendly and easy to process.

[0058] In a seventh method step 62, at least one prosthesis 10 is manufactured using the negative impression of the prosthesis and the positive mold of the affected body part 26. For this purpose, silicone to be cross-linked is poured into the negative impression of the prosthesis, and the positive mold of the affected body part 26 is pressed into the negative impression of the prosthesis in order to form the precise transition of the prosthesis 10 to the finger stump. After cross-linking of the silicone, the shape predetermined by the negative impression as well as the transition of the prosthesis 10 predetermined by the positive mold of the affected body part 26 are retained. Since the negative impression can be used multiple times, a variety of prostheses 10 for different skin tones can be produced using appropriately colored silicones. This provides the patient with a wide selection of differently colored prostheses that can be manufactured quickly and cost-effectively.

[0059] Changes to the finger stump can also be easily accommodated by creating a new digital image of the finger stump 20 and a new positive mold of the finger stump 26 using the 3D printer. In most cases, the positive mold of the prosthesis 24 does not need to be altered, i.e., reprinted, so the existing negative impression of the prosthesis can be reused. By pressing the new positive mold of the finger stump 26 into the silicone contained in the negative impression, a prosthesis 10 can be produced with a new, adapted transition to the modified finger stump.

[0060] As further shown in Figure 4, mold locks 30 can be inserted into the digital images of the affected body part 20 (not shown) and the prosthesis 22. Attaching mold locks 30 to the positive mold of the affected body part 26 (see Figure 5) ensures their correct fit in the negative impression of the prosthesis, thereby simplifying manufacturing. Preferably, the mold locks 30 are designed such that only one possible arrangement of the positive mold of the affected body part 26 exists in the negative impression of the prosthesis. The mold locks 30 are, for example, conical in shape.

[0061] In the above description, it should be noted that method steps 50, 52, 58, and 60 are fundamentally optional for the invention. This circumstance is indicated in Figure 1 by the fact that method steps 50, 52, 58, and 60 are depicted in a dashed box. For example, the digital images of the finger pair can alternatively be generated directly on the patient's finger pair using a 3D scanner. Furthermore, it is possible for the prosthesis 10 to be printed directly based on the digital image of the prosthesis 22.

[0062] Finally, Figure 7 shows a schematic representation of a device 100 according to one embodiment. The device 100 is suitable for producing a prosthesis 10 for a body part of a limb, in particular for producing a prosthesis 10 for a finger stump as described with regard to the method according to Figure 1 and in Figures 2 to 6.

[0063] The device 100 comprises a detection unit 102, an electronic control unit 104, and a 3D printer 106 with a print resolution of less than 0.1 mm. The 3D printer 106 is preferably an SLS or synthetic resin 3D printer. The detection unit 102 is configured to create digital images of impaired 20 and intact body parts of a limb. The electronic control unit 104 is configured to create a digital image of a prosthesis 22 for the impaired body part using a mirrored digital image of the intact body part and a digital image of the impaired body part 20. The 3D printer 106 is configured to produce at least one prosthesis 10 for the impaired body part using the digital image of the prosthesis 22.This can be done either directly or indirectly, for example by using a mold kit to make negative impressions (not shown).

[0064] List of reference symbols

[0065] 10 Prosthesis for a body part of a limb

[0066] 12 Negative impression of an affected body part

[0067] 14 Negative impression of the corresponding intact body part

[0068] 16 Positive form of an impaired body part

[0069] 18 Positive form of the corresponding intact body part

[0070] 20 Digital image of the affected body part

[0071] 22 Digital image of the prosthesis

[0072] 24 Positive form of the prosthesis

[0073] 26 Positive form of the affected body part

[0074] 28 recessed area

[0075] 30 molded locks

[0076] 50 first procedural step

[0077] 52 second procedural step

[0078] 54 third procedural step

[0079] 56 fourth procedural step

[0080] 58 fifth procedural step

[0081] 60 sixth procedural step

[0082] 62 seventh procedural step

[0083] 100 Device for producing a prosthesis for a body part of a limb

[0084] 102 Recording unit

[0085] 104 electronic control unit

[0086] 106 3D printers

Claims

Patent claims 1. A method for producing a prosthesis (10) for a body part of a limb, comprising the steps of: Creating (54) a digital image of an impaired body part (20) of a limb and a digital image of a corresponding intact body part of the limb, Creating (56) a digital image of a prosthesis (22) for the affected body part using a mirrored digital image of the intact body part and the digital image of the affected body part (20), Producing (62) at least one prosthesis (10) for the affected body part using the digital image of the prosthesis (22) and a 3D printer (106) with a printing resolution of less than 0.1 mm.

2. The method according to claim 1, wherein the prosthesis (10) for the affected body part is printed directly from the digital image of the prosthesis (22) by the 3D printer (106).

3. The method of claim 1, further comprising the steps of: Creating (58) a positive mold of the prosthesis (24) and a positive mold of the affected body part (26) using the digital images of the prosthesis (10) and the affected body part and the 3D printer (106), Creating (60) a negative impression of the prosthesis using the positive mold of the prosthesis (24) and Manufacturing the prosthesis (10) for the affected body part using the negative impression of the prosthesis.

4. The method according to claim 3, wherein, during the manufacture of the prosthesis (10) for the affected body part, a textile fabric is embedded in the manufactured prosthesis (10).

5. The method according to claim 3 or 4, wherein air holes and / or mold locks (30) are inserted into the digital images of the affected body part (20) and the prosthesis (22).

6. Method according to one of the preceding claims, wherein the prosthesis (10) for the affected body part comprises a relief cushion made of a soft silicone and / or a soft 3D-printed synthetic resin, wherein the digital image of the affected body part (20) is extended by a predetermined thickness of the relief cushion and / or the digital image of the prosthesis (22) is supplemented by a relief area provided for the relief cushion.

7. The method according to claim 6, wherein, during production of the prosthesis (10) for the impaired body part using the negative impression of the prosthesis, a first silicone is poured into the negative impression, the positive shape of the extended impaired body part (26) is pressed into the negative impression and, after the first silicone has hardened, a second silicone is poured onto the first silicone in the negative impression, wherein the second silicone is softer than the first silicone or wherein the prosthesis (10) for the impaired body part is printed from the digital image of the prosthesis (22) by the 3D printer (106) and the softness of the 3D-printed synthetic resin in the relief region is achieved by reducing the material density of the synthetic resin and / or by using a further 3D-printed synthetic resin, wherein the further synthetic resin is softer than the synthetic resin used for the remaining prosthesis (10).

8. Method according to one of the preceding claims, wherein a color tone determination of the limb is carried out and the prosthesis (10) is manufactured in a color based on the determined color tone.

9. Method according to one of the preceding claims, wherein the 3D printer (106) used is an SLS or resin 3D printer.

10. Method according to one of the preceding claims, wherein a size of the digital image of the prosthesis (22) and / or the digital image of the affected body part (20) is adapted such that the produced prosthesis (10) can be attached to the affected body part by means of a suction effect.

11. A method according to any one of the preceding claims, further comprising the steps of: Creating (50) a negative impression of the affected body part (12) and a negative impression of the corresponding intact body part (14) and creating (52) a positive mold of the affected body part (16) and a positive mold of the intact body part (18) using the negative impressions (12, 14), wherein the digital images of the affected body part (20) and the intact body part are created using the positive molds (16, 18).

12. Method according to one of the preceding claims, wherein the manufactured prosthesis (10) comprises a core made of a silicone mixture with fillers.

13. Method according to one of the preceding claims, wherein a recessed area (28) for an object to be inserted is provided in the digital image of the prosthesis (22).

14. A device (100) for producing a prosthesis (10) for a body part of a limb, comprising: a detection unit (102) configured to create digital images of impaired (20) and intact body parts of a limb, an electronic control unit (104) configured to create a digital image of a prosthesis (22) for the impaired body part using a mirrored digital image of the intact body part and a digital image of the impaired body part (20), and a 3D printer (106) with a print resolution of less than 0.1 mm, configured to produce at least one prosthesis (10) for the impaired body part using the digital image of the prosthesis (22).

15. The apparatus (100) of claim 14, further comprising a mold kit for making negative impressions.

Images