Improved method for aiding the manufacture of a limb prosthesis using a positive socket mould, and assembly for placing a fastener between a socket and a prosthesis connection element

Abstract

The invention relates to an improved method for manufacturing a prosthesis (1') from a positive mould (110), for fitting to a residual limb of an amputee. The method comprises 3D modelling of the inner surface of an existing socket (2) comprising a 3D model (44) of the surface in a spatial reference system (10) and automatic modification of the 3D model (44) in order to optimize the arrangement of an artificial limb (3) in the socket (2') to be manufactured. The method further comprises determining a position of a fastener (116) in the spatial reference system (10) with the aid of a guide (112) for placement of the fastener (116). The invention also relates to a manufacturing aid assembly (100) configured to aid in the manufacture of a socket according to the method of the invention and comprising a positive mould (110) and the placement guide (112).

Description

[0001] IMPROVED METHOD FOR AID IN THE MANUFACTURE OF A LIMBS PROSTHESIS USING A POSITIVE SOCKET MOLD, AND ASSEMBLY FOR PLACEMENT OF AN ATTACHMENT BETWEEN A SOCKET AND A PROSTHETIC CONNECTING ELEMENT.

[0002] TECHNICAL FIELD

[0003] The present invention relates to an improved method for manufacturing a prosthetic limb from a positive mold obtained from a digital model. At least one embodiment relates to determining one or more attachment points for a fastener on an attachment surface between a hand-shaped prosthetic socket and an artificial limb of that prosthesis; and at least one embodiment relates to a method for obtaining a fastener placement guide from a digital model of a socket surface. The invention also relates to a prosthetic attachment placement guide.

[0004] PREVIOUS STATE OF THE ART

[0005] The fabrication of a prosthetic limb, as illustrated in Fig. 1, involves creating a temporary prosthetic socket into which a residual limb is inserted. This temporary socket is molded to the shape of the residual limb and fitted as closely as possible to the intended limb. Recent technologies and techniques allow prosthetists to create a three-dimensional model of the inner surface of a temporary socket previously molded manually on a residual limb. They can then digitally adapt or refine this 3D model to optimize its shape, as illustrated in Fig. 2, particularly to increase wearer comfort and optimize the fixation of the artificial limb to the socket. A final socket can then be 3D printed or machined from the resulting 3D model and digitally modified.Unfortunately, not all prosthetic practitioners have the technical means to perform 3D modeling and / or adjustments based on a 3D model, as well as 3D printing of a prosthetic socket, and this situation can be improved. Furthermore, although some practitioners may have the necessary equipment to work from a 3D model, the materials and components required may still be too expensive. DESCRIPTION OF THE INVENTION.

[0006] One object of the present invention is to provide a method to assist in the manual fabrication of a temporary socket or a so-called "final" or "definitive" socket for a limb prosthesis, by giving prosthetists access to advantages inherent in 3D modeling, on which the most recent techniques are based, even if these practitioners do not have access to 3D modeling and 3D model processing tools, or if their use proves too costly. In particular, a placement guide is proposed for determining the precise position of a mechanical attachment of an artificial limb on a socket to be fabricated on a positive mold representing the inner surface of a limb socket.

[0007] To this end, a set of aids for the manufacture of a prosthetic limb is proposed, the set comprising: a positive mold having a surface shape complementary or substantially complementary to an internal surface of a first socket of a prosthetic limb and having at least one first visual reference mark, a positioning guide comprising at least one arm and one end of which has a second reference mark, intended to coincide with said first visual reference mark or with a position of the positive mold established in reference to the first visual reference mark said arm of said guide further carrying an element for holding and positioning in space a mechanical attachment configured to allow the fixing of an artificial limb on a surface of a material applied to said positive mold in order to form a second socket of said prosthetic limb.

[0008] According to one embodiment, the assembly for manufacturing a prosthetic limb comprises at least four branches between which the support and positioning element is arranged and of which one or more branch ends present the support and positioning element, and the second reference being a visual reference.

[0009] According to one embodiment, the prosthesis manufacturing aid assembly further includes a hoop configured to hold in position and stabilize the placement guide against the positive mold.Another object of the invention is a method for manufacturing a prosthetic limb, the method comprising the use of a prosthetic limb manufacturing aid assembly as previously described and comprising the steps: placing the positive mold of the manufacturing aid assembly on an ideally flat reference work surface, positioning the positioning guide of the manufacturing aid assembly so that the part of the mold having the first visual reference mark is in contact with the part of the guide having the second visual reference mark, the first and second visual reference marks being arranged opposite each other or coinciding with each other, assembling a fastener on the holding and positioning element in the space of said positioning guide, and sealing the fastener and a surface of the positive mold or of an envelope positioned on the positive mold, arranged opposite the fastener.

[0010] Another object of the invention is a method for manufacturing a prosthetic limb as described above and further comprising a deposit of a layer of material around the positive mold, on a surface of the positive mold or on an envelope positioned on the positive mold, the deposited material sealing or permanently encircling the attachment to form the second prosthesis socket equipped with an attachment then configured for the fixation of an artificial limb.

[0011] Another object of the invention is a method for manufacturing a prosthetic limb as described above and further comprising a preliminary manufacturing step by 3D printing, machining or laser cutting of the positive mold from a 3D digital model obtained by modeling an inner surface of said first prosthesis socket.

[0012] The invention also relates to a method for manufacturing a prosthetic limb, further comprising a preliminary manufacturing by 3D printing, machining or laser cutting of the placement guide from a 3D digital model obtained by modeling an inner surface of the first prosthesis socket.

[0013] The invention further relates to a method for manufacturing a prosthetic limb comprising further a preliminary manufacturing by 3D printing, machining or laser cutting of the positive mold and the placement guide from a 3D digital model obtained by modeling an inner surface of the first prosthesis socket, the positive mold and the placement guide being manufactured in the same element (or part) and being separable by means of pre-cuts or breakable parts arranged during the manufacture of this single element (or single part).

[0014] Another object of the invention is a method for manufacturing a manufacturing aid assembly as previously described, said method comprising the steps of: obtaining a first 3D digital model, representative of the inner surface of the first socket, by digitizing the inner surface of the first socket, with reference to a spatial reference frame comprising at least one reference point, determining a second 3D digital model, representative of the shape of the positive mold of the second socket, from the first 3D digital model, determining a third 3D digital model, representative of the shape of said positioning guide, from the second 3D digital model, and manufacturing by 3D printing, machining, or laser cutting said positive mold and / or said positioning guide.

[0015] According to one variant, the aforementioned manufacturing process for a manufacturing aid assembly further includes a step of determining a fourth 3D digital model, representative of the shape of the band.

[0016] Finally, the invention also relates to a computer program product comprising program code instructions for executing the steps of a manufacturing process for a set of manufacturing aids as previously described when this program is executed by a processor of an information processing unit and an information storage medium comprising such a computer program product.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The features of the invention mentioned above, as well as others, will become clearer upon reading the following description of an exemplary embodiment, said description being made in relation to the accompanying drawings:

[0019] [Fig. 1] schematically illustrates an example of a prosthesis, adapted to a lower limb, and whose adjustable elements have been adjusted to be adapted to a wearer of the prosthesis;

[0020] [Fig. 2] schematically illustrates a modeling system for the inner surface of a prosthesis configured for generating a 3D digital model of the inner surface of a prosthesis; [Fig. 3] schematically illustrates a so-called final prosthesis made from the provisional prosthesis shown in Fig. 1 and whose characteristics have been optimized through 3D modeling performed using the modeling system illustrated in Fig. 2;

[0021] [Fig. 4] schematically illustrates a determination of the optimized positioning of a mechanical attachment relative to a model of the inner surface of a prosthetic limb socket, operated by a digital system after digitization of the inner surface of F socket;

[0022] [Fig. 5] schematically illustrates a 3D printing system configured to print a positive mold of complementary or substantially complementary shape to the shape of the modeled inner surface of a socket;

[0023] [Fig. 6] schematically illustrates a set of aids for the manufacture of a prosthetic limb according to one embodiment;

[0024] [Fig. 7] illustrates details of positioning a mechanical attachment using the prosthesis manufacturing aid assembly already shown in Fig. 6, according to one embodiment;

[0025] [Fig. 8] illustrates the entire aid for manufacturing a prosthetic limb already shown in Fig. 7, before assembly, according to one embodiment;

[0026] [Fig. 9] is a diagram illustrating steps in a process for assisting in the manufacture of a prosthetic limb using a set of aids for the manufacture of a prosthetic limb, according to an embodiment;

[0027] [Fig. 10] schematically illustrates an example of the architecture of a controller configured for the design of a set of aids to manufacture a prosthetic limb from a 3D digital model of an internal surface of a prosthetic limb;

[0028] [Fig. 11] is a flowchart illustrating the steps in a design and manufacturing process for a set of manufacturing aids according to one embodiment; and,

[0029] [Fig. 12] schematically illustrates details of positioning a mechanical attachment using a prosthesis manufacturing aid set, according to an embodiment variant using an articulated arm or a robot as a placement guide.

[0030] DETAILED EXPLANATION OF IMPLEMENTATION METHODS

[0031] Figures 1, 2 and 3 illustrate existing techniques for manufacturing prosthetic limbs using 3D modeling means of a provisional socket 2 of a prosthetic limb formed on the residual limb of a user (or wearer, or patient) as well as a 3D three-dimensional model 44 of the inner surface of the provisional socket 2, which can be digitally modified and retouched.

[0032] Figure 1 is a schematic representation of an example of a limb prosthesis 1. In this example, limb prosthesis 1 is a temporary lower limb prosthesis, also called a temporary tibial prosthesis, comprising an artificial terminal part 4, referred to here as the "artificial foot." However, prosthesis 1 could also be a non-temporary prosthesis, called a "definitive prosthesis," which is to be reproduced. The temporary prosthesis 1 is considered temporary because it includes a temporary socket 2, manually shaped by a practitioner to be progressively adapted to the morphology of the wearer of the temporary prosthesis. This wearer will later receive a final, optimized prosthesis manufactured from the temporary prosthesis 1. The temporary socket 2 is configured to be fitted onto a residual limb of the wearer. The temporary prosthesis 1 includes an artificial limb 3.The artificial limb 3 comprises the artificial foot 4 and a connecting element 5 (an artificial tibia, as in the example described here) for mechanically connecting the artificial foot 4 to the temporary socket 2. The artificial limb 3 includes a first set of fixation called the "distal fixation" 6, which is adjustable, of the ball-and-socket type, and lockable in position, between the artificial foot 4 and the connecting element 5, and a second set of fixation called the "proximal fixation" 7, between the connecting element 5 and the temporary socket 2. The distal fixation 6 comprises two complementary parts 6a and 6b, which are inserted one inside the other (parts 6a and 6b of the distal fixation assembly 6 are not detailed in Fig. 1). Parts 6a and 6b constitute an assembly commonly known as a "pyramid" used in the field of limb prostheses. Part 6a is integral with the artificial foot 4.Part 6b is integral with the connecting element 5. Each of parts 6a and 6b includes means for adjusting and locking (blocking) in position, operating in combination with means for adjusting and locking in position of the other part 6a and 6b of the distal fixation 6. Thus, the distal fixation 6 is configured to adjust and lock in position the foot 4 and the connecting element 5, thanks to the combined effect of parts 6a and 6b. Fig. 1 illustrates that, according to the reference settings made when the temporary prosthesis 1 is worn by the intended wearer, the best setting, shown in Fig. 1, is such that the connecting element 5 has a longitudinal axis 50 inclined in a space referenced by an orthonormal coordinate system 10 comprising directions X, Y, and Z.The X, Y, and Z directions are pairwise perpendicular, such that a plane defined along the X and Y directions is horizontal, and a plane defined along the X and Z directions, or even along the Y and Z directions, is vertical. The entire temporary prosthesis 1, in its position best suited to the patient, or at least considered as such, is referenced and located in space with respect to a first predefined reference point 401 of the artificial foot 4 when the artificial foot is positioned in a predetermined reference position, for example, when the artificial foot 4 is placed on a reference surface 101 parallel to a plane defined along the X and Y directions (a horizontal plane).

[0033] According to another example, adjustable distal fixation can be implemented without using a "pyramid" system as previously described, but through one or more pivot links, or even a ball joint of any type that can be locked in position.

[0034] According to yet another example, adjustable distal fixation can be implemented using a connecting element made of a deformable material when a force greater than a predetermined threshold is applied to it; for example, a metal bar that can be deformed using specific tools dedicated to achieving such an adjustment.

[0035] It should be noted that the determination of a predetermined reference position, and therefore of a reference setting in relative position, with respect to each other, of the arrangement of all the elements which make up the prosthesis, depends on the type of prosthesis and in particular on the type of the artificial end part 4 to be assembled to the connecting element 5. Thus, for example, a reference position along the torso of a wearer can be determined when the artificial end part is an arm; a reference position with respect to the arm can be determined when the artificial end part 4 is a hand, and so on.

[0036] Depending on the type of artificial terminal part 4 assembled on the prosthesis, the connecting element 5 can have many different shapes so as to provide structural features implementing all or part of the functions of shoulder, hip, knee, ankle, for example, but also more generally to operate a solid connection between a socket adapted to a residual portion of the body, on the one hand, and to an artificial limb, on the other.

[0037] Fig. 2 illustrates the positioning of the provisional prosthesis 1 in a modeling system 400 of the inner surface of the provisional socket 2. The system 400 includes a second reference space 40 defined by directions X', Y' and Z' respectively parallel to the directions X, Y and Z of the first reference space 10, as well as a support including the reference point 201. Cleverly, the reference point 201 is included in a distal fixation assembly identical to the distal fixation assembly of the provisional prosthesis 1. According to the embodiment described, the reference point 201 is implemented by the intersection of the adjustment axes of a so-called "pyramid" linkage assembly such as the distal fixation assembly 6 illustrated in Fig. 3 and composed of elements 6a and 6b.Using a pyramid as the reference point 201 of the system 400 for modeling the inner surface of the temporary socket 2 advantageously allows for the fixing of the connecting element 5 to which the temporary socket 2 is attached, while maintaining the positional adjustment of the connecting element 5 relative to the spatial reference frame 10 (reference adjustment). Indeed, if the decoupling of the fixing element 5 and the artificial foot 4 is achieved by loosening only two adjacent screws among the four screws of the pyramid system 6, and then the connecting element 5 is re-coupled to an element similar to element 6a of the distal fixation 6, including the reference point 201, by tightening the two previously loosened screws, the relative positioning of the assembly composed of the connecting element 5 and the temporary socket 2 with respect to the spatial reference frame 10 is maintained.This obviously implies that the pyramid element serving as a fixator and including the reference point 201 is fixed in the fixator assembly in a position such that the respective orientation directions of the settings in the second reference space 40 are parallel to the X, Y and Z directions of the reference space 10. Obviously, the reference point could be another point of the provisional prosthesis, provided that it is possible to define a relative position between the position of the provisional prosthesis in the second reference space 40 with respect to the first reference space 10.

[0038] The modeling system 400 includes a distance measuring device 42 connected to a control unit 41 via a bidirectional communication link 43. According to one embodiment, the distance measuring system 42 is mobile and can be moved along the X', Y' and Z' directions of an orthonormal frame (spatial reference frame) 11, in the reference space 40. The movements of the distance measuring device 42 in the reference space 40 can be operated manually or automatically.That is to say, the distance measuring device 42 can be guided manually by an operator or guided along the X', Y', and Z' directions by actuators, such as stepper motors, for example, under the control of the control unit 41 executing software routines designed for this purpose, and comprising a user interface accessible via the control unit 4L. In all cases, the modeling system 400 includes means for determining the precise position in the second reference space 40, thanks to a set of position sensors. Advantageously, and according to one embodiment of the invention, the distance measuring device 42 comprises a rotating arm (or shaft) 421 at the end of which is fixed a measuring head 422 (these elements are not shown in Fig. 4 to improve readability).In one embodiment, the measuring head 422 of the measuring device 42 includes a light wave transmitting-receiving module configured to determine the distance between the transmitting-receiving module and an interface positioned opposite it, using a "time-of-flight" method. In one embodiment, the light wave is a laser beam. This configuration advantageously allows the distance between the measuring head and a point on the inner surface of the temporary socket 2, located opposite the measuring head 422, to be determined when all or part of the arm 421 and the measuring head 422 are inserted into the temporary socket 2.Thus, thanks to the modeling system 400, it is possible to determine a model 44 representing the inner surface of the provisional socket 2 in the reference space 40, and therefore, consequently, in the reference space 10, since the distance between the reference points 401 of the artificial foot 4 of the provisional prosthesis 1 and the fixation and reference point 201 is known, and can be expressed in terms of coordinates along the X, Y and Z directions of the reference space 10 or along the X', Y' and Z' directions of the reference space 40. In Fig. 4, the 3D model 44 representing the inner surface of the provisional socket 2 is shown on the screen of the control unit 41, for the purpose of fully illustrating the modeling system 400.Naturally, the information representing each of the measurement points, which together constitute modeling points of the socket's inner surface, can be stored in the working memory of the control unit 41 or in memory external to the control unit 41 and accessible from it. The control unit 41 is generally configured to perform changes of coordinate systems or reference spaces, allowing it to convert the first coordinates of one or more points of an object in a first coordinate system or spatial reference frame into the second coordinates of these same points in a second coordinate system or spatial reference frame, and vice versa. As a result, after digitizing an object in a first coordinate system or spatial reference frame, the control unit can determine three-dimensional models of parts with complementary shapes to be positioned in another coordinate system or spatial reference frame.Of course, the scanning method described here is not exhaustive, and other 3D scanning methods can be used to model the inner or outer surface of a socket. For example, a handheld 3D scanner of the Einstar type (registered trademark) from the supplier Shining 3D (registered trademark) can be used when the socket whose inner surface is to be scanned is positioned on a calibration support equipped with a distal fixation system similar to the distal fixation assembly 6, for example, a plate with a pyramid and visual markers providing a three-dimensional reference space (or 3D datum).

[0039] Figure 3 shows a final prosthesis 1', the fabrication of which is simplified by the manufacturing aid system described. The final prosthesis 1' comprises the same elements as the provisional prosthesis 1, except for the socket and the proximal fixation 7, which is replaced by a final proximal fixation 7'. In the final prosthesis 1', the provisional socket 2 is replaced by a final socket 2'. However, the fixation parameters and the settings of the distal fixation assemblies 6 and proximal fixation 7' ​​are different from those of the distal fixation 6 and proximal fixation 7 implemented for the provisional prosthesis 1. Figure 3 is intended to illustrate one of the advantages of using the so-called final prosthesis 1', which includes the so-called final socket 2'.Indeed, in addition to the strength of the materials, optimized weight, and robustness, for example, the assembly of the elements of the final prosthesis 1' aims to achieve a vertical or nearly vertical positioning of the longitudinal axis 50 of the fixation element 5. This allows, in the example of the (tibial) prosthesis described here, for an optimized absorption of the mechanical weight-bearing forces present during the use of the final prosthesis 1' by its wearer. Furthermore, an adjustment of the shape of the final socket 2' at the level of the proximal fixation 7', relative to the shape of the provisional socket 2, near the proximal fixation 7, not only allows for a vertical or near-vertical positioning of the fixation element 5 but also for an adjustment of the distal fixation 6 with an adjustment range (or excursion) evenly distributed in two opposite directions of the same adjustment direction.In other words, the setting of the distal fixation 6 can be repositioned "to neutral" due to an adjustment of the shape of the final socket 2', at the level and near the proximal fixation 7', relative to the shape of the provisional socket 2. The excursions of setting of the distal fixation 6, resulting from the reference setting made during repeated trials with the wearer, are then compensated by an adjustment of the shape of the final socket 2' at the level of the proximal fixation 7' ​​and by the configuration of the proximal fixation 7' ​​which results therefrom, considered as a whole.

[0040] These characteristics of the final prosthesis 1', comprising the final socket 2', compared to the provisional prosthesis 1 comprising the provisional socket 2, are obtained through digitization techniques that allow the second socket 2', called the "final socket," to be manufactured, for example by machining or 3D printing, from the determined (digitized) three-dimensional model, possibly modified. Fig. 4 is an enlarged view of the three-dimensional model 44 representing the inner surface of the provisional socket 2. A lower portion 44e represents the surface of the base of the provisional socket 2 (or the lower part of the provisional socket 2). Advantageously, it is possible to automatically define, through modeling, an outer surface of a socket to be manufactured that reproduces the inner surface of the socket 2.In one embodiment, the control unit 41 executes an algorithm to define a volume corresponding to a thickness around the modeled inner surface 44 and can determine a volume shape to meet specific criteria or given constraints. Thus, the control unit 41 defines support and fixing surfaces for the connecting element 5, taking into account the positioning of the inner surface modeled by the three-dimensional model 44 relative to the reference point 401 of the artificial foot 4. This is made possible by the various spatial references used, and in particular by the use of the fixing pyramid to fix the connecting element 5 coupled to the temporary socket 2 in the reference space 40, before scanning the inner surface of the temporary socket 2 using the detection device 42.

[0041] The bearing and fixation surfaces determined by the control unit 41 can vary and obviously depend on the type of artificial limb to be fixed to the socket. According to the prosthesis example described, the control unit 41 advantageously allows for the definition of a reference point PI in the reference space 10 (determined by the X, Y, and Z directions) to be used to define the fixation point of an artificial limb attachment 116. The attachment 116 is an element of the proximal fixation of the tibial prosthesis illustrated in an example embodiment.

[0042] Modifications made to the 3D model 44 aimed at optimizing the comfort of the prosthesis wearer and / or the mechanical characteristics of fixation and load transfer, for example, can be carried out automatically, using dedicated calculation modules of the control unit 41 executing algorithms adapted for this purpose, but also carried out under the control of an operator such as a prosthetist, who is able to modify the stored three-dimensional model by entering or modifying shape and position parameters (local thicknesses, reliefs, cavities, etc.) of the socket via a human-machine interface operating in connection with the control unit 4L. Obviously, the modification of a three-dimensional surface or volume model of a prosthesis socket can combine automated modifications and modifications carried out by entering or modifying parameters under the control of an operator.

[0043] Ingeniously and advantageously, the control unit is also used to define a placement guide device or system, based on point PI, the three-dimensional model 44 of the socket's inner surface, and the shape of the attachment 116, whose dimensions are predetermined. The term "placement guide" here refers to a limb attachment placement guide for a socket to be manufactured. This involves positioning the attachment 116, also referred to here as the mechanical attachment 116, at a precise location (PI, or another point defined in relation to point PI), thus optimizing the comfort and / or mechanical function of the prosthesis to be manufactured, as illustrated previously in relation to Figs. 1, 2, and 3.

[0044] Since the prosthesis must be made manually by modeling on a positive mold, the use of a placement guide device or system advantageously allows the attachment 116 to be positioned and held in position while the attachment 116 is sealed onto a surface positioned on the positive mold 110, for example by gluing, before material is applied to the positive mold 110 to form the socket around this positive mold and at least partially around the attachment 116. The term "positive mold" here refers to a mold whose outer surface has a shape that is complementary or substantially complementary to the inner surface of a prosthesis socket.The terms "substantially complementary" here refer to a complementary form possibly modified at the margin to make local adjustments to improve the comfort of the wearer or an anchoring or mechanical attachment position of an element to a socket made from the mold.

[0045] It is thus advantageously possible to reposition the proximal fixation 7' ​​relative to the axis 50 of the connecting element 5, so as to obtain an assembly of the final socket 2' and the connecting element 5 which allows for the most vertical possible position, or substantially vertical, of the connecting element 5, when the final prosthesis 1' is worn by a wearer, while best meeting the comfort conditions tested and obtained during the preliminary testing phase of the provisional prosthesis 1. As a result, the final prosthesis 1' will be as comfortable as possible, while presenting an optimized configuration for the absorption of mechanical forces during use and while offering well-distributed adjustment possibilities (substantially equal excursions) in both directions of the same direction for the adjustment of the distal fixation 6.

[0046] That being said, not all prosthetists have automated tools capable of operating a machining or 3D printing from a digital model or even capable of operating by combining these two techniques, which is why the placement guide device or system according to the invention and its use for the manufacture of a prosthesis, cleverly and advantageously allow prosthetist practitioners to manually manufacture a limb prosthesis from a 3D model generated via the aforementioned tools and taking advantage of the described benefits allowing to optimize the characteristics of this prosthesis.

[0047] Fig. 5 illustrates a 3D printing manufacturing system configured for the three-dimensional printing of a positive mold 110 representative of the internal shape of the final socket 2'. According to one embodiment, this system includes a 3D printer 45. The system consists of the control unit 41, used in the modeling system 400, or any similar system, into which a three-dimensional model derived with or without modifications of the three-dimensional model 44 has been transferred, connected to the 3D printer 45.A bidirectional link 43 between the control unit 41 and the 3D printer 45 allows the control unit 41, operating under dedicated software routines, to control the 3D printer 45 in three dimensions. This control unit 41 prints the prosthesis manufacturing aid assembly 100 from the three-dimensional model 44, which may be modified by one or more dedicated applications executed by the control unit 41 (an example of whose architecture is illustrated in Fig. 10). In one embodiment, the prosthesis manufacturing aid assembly 100 comprises the positive mold 110 and a positioning guide 112 that allows for precise positioning of the attachment 116 relative to the positive mold 110.

[0048] The 3D printing system using the 45 3D printer advantageously allows printing of the 110 positive mold as well as a mechanical fastener placement guide, under the control of the 4L control unit.

[0049] Indeed, the control unit 41 is configured to determine any object or volume from a set of points determined in a spatial frame (or reference space) in which a set of points representative of the digitized inner surface of a socket is determined.

[0050] In one embodiment, the positive mold 110 and the positioning guide 112 are manufactured as two separate objects or assemblies. In another embodiment, the positive mold 110 and the positioning guide are manufactured as a single object but with predefined points of weakness, also called "breakable parts," which allows the positive mold 110 to be separated from one or more other elements forming the positioning guide 112 or intended to form the positioning guide 112 after an assembly step.

[0051] Of course, the manufacturing methods described above are not exhaustive, and other methods for manufacturing the positive mold 110 and the positioning guide 112 may be used. For example, the positive mold 110 could be produced by machining operations (milling, for instance), and the positioning guide 112 could be produced by milling or by cutting with a laser cutting tool. The various manufacturing methods, such as machining, additive manufacturing, and laser cutting, can of course be combined.

[0052] It should be noted that the outer surface of the positive mold 110 is very important, as it serves to define the inner surface of the socket to be made, which will be worn by the wearer of the prosthesis to be manufactured. This is based on a scan of the inner surface of a previous socket (temporary or otherwise), whether modified or not. However, this does not preclude the creation of a cavity or any other shape within the positive mold 110, particularly for the purpose of attaching the mold to a work surface in order to apply a material to fabricate a prosthetic socket. More generally, the interior of the positive mold 110 can be modified to meet various constraints, for example, to save material or to insert one or more fastening elements, provided that the positive mold 110 is sufficiently robust and practical to meet the manufacturing requirements of a prosthesis using this mold.

[0053] Fig. 6 schematically illustrates, in perspective, a set 100 of aids for the manufacture of a prosthesis comprising the positive mold 110 and a placement guide 112.

[0054] In the example shown, the positive mold 110 is a separate element from the positioning guide 112, and a calibrated clamping ring 114 ensures stable and correct relative positioning of the positive mold 110 and the positioning guide 112 without any movement. The clamping ring 114 is first determined by the control unit 41, in the form of a 3D digital model, from a 3D digital model of the positioning guide 112, which 3D digital model of the positioning guide 112 is determined from the 3D digital model of the positive mold 110.

[0055] Cleverly, at least one arm of the positioning guide 112 includes a visual marker 112n intended to coincide with a visual marker 11On of the positive mold 110 when the positioning guide 112 is positioned in contact with the positive mold 110 or when a single arm is securely fixed on a common base (a common support) with the positive mold 110 which includes a marker 11. According to one embodiment, the positioning guide 112 includes a plurality of arms and at least two of these arms then include a predetermined visual marker 112n intended to coincide with a dedicated visual marker 11On of the positive mold 110. According to the embodiment example described in relation to Fig. 6, a second visual reference 112n' of a branch of the positioning guide 112 is determined to be positioned opposite a second visual reference 11 On' of the positive mold 110. It should be noted that the term "visual references" here refers to any reference that can be perceived visually.Thus, it can be a simple marking, but also a predetermined mechanical feature designed to complement a second mechanical feature, allowing one to be fitted into the other. For example, a first marker could be a cylindrical mechanical feature (a pin or a cylindrical lug) designed to be inserted into a bore of complementary shape. In yet another example, a first marker could be a square protrusion designed to be inserted into a square cavity, and so on. Therefore, a visual marker designed to coincide with another visual marker can be defined as two complementary surfaces configured to achieve precise relative positioning between two parts or elements (here, the positioning guide 112 relative to the positive mold 110).The complementary shapes used can then be any shapes as long as, in pairs, they allow for error correction in position and precise positioning of the placement guide 112 relative to the positive mold 110.

[0056] Fig. 7 schematically illustrates the positioning of a portion 112m of the placement guide 112 configured to operate and functioning as a mechanical attachment support for a prosthetic artificial limb. This mechanical attachment support performs the functions of holding and positioning the mechanical attachment of the artificial limb in space. The prosthesis fabrication aid assembly 100, shown in Fig. 7, comprises the positive mold 110, the placement guide 112, and the band 114. The placement guide 112 comprises four arms 112a, 112b, 112c, and 112d, each arranged in an overall "L" shape and converging towards the central portion 112m.According to one embodiment, the central portion 112m comprises one or more bores or threads configured for the temporary attachment of the attachment 116 to the positioning guide 112, with reference to the reference point PI which precisely defines the position and orientation of the attachment 116 in combination with the central portion 112m of the positioning guide 112, the shape of which is determined under the control of the control unit 41 and 3D modeling. Such an arrangement advantageously allows the artificial limb attachment 116 to be positioned and fixed to the positioning guide 112 in a predetermined position within the reference space (spatial frame of reference) used, before sealing the attachment 116 to a surface affixed to the positive mold 110, prior to the molding of the prosthetic socket to be manufactured by a prosthetist or by an operator working under the supervision of a prosthetist.The socket manufacturing steps described herein are intentionally simplified to enhance readability, as they do not directly contribute to understanding the invention. A person skilled in the art, particularly in prosthetics, will be able to determine the prerequisites and steps for manufacturing a socket from a positive mold and a limb attachment positioned at a precise point relative to that mold, according to at least one embodiment and with the aid of an attachment placement guide. For example, a first pocket of PVA or PVC material can be applied (threaded) by an operator onto the surface of the positive mold, onto which a layer of re-impregnated fibers will be applied. This is then covered with a second pocket threaded over the entire assembly, and the space between the two pockets is then filled with a material such as, for example, resin.Thus, when it is stated previously that the fastener 116 is sealed onto the mold, it is actually positioned against the mold, flush with it or close to it, but is isolated by the first pocket acting as an insulating interface. The fastener 116 is actually sealed within the socket formed on the positive mold, and close to or against the positive mold.

[0057] Fig. 8 illustrates an example of an embodiment of the prosthetic limb fabrication aid assembly 100, in which the positive mold 110 and the positioning guide 112 are manufactured and supplied as separate components. According to the described embodiment, the positioning guide 112 is supplied as four arms 112a, 112b, 112c, and 112d, also supplied as separate components. In this embodiment, the ends of the arms then form the central part 112m of the positioning guide 112 when brought together during an assembly operation. According to this example, the assembly includes the fastener 116, and the band 114, as well as a set 116s of screws provided and configured to achieve a positioning and fixing of the fastener 116 against the central part 112m of the positioning guide 112, precisely between the central part 112m and the positive mold 110. According to the embodiment example of the assembly 110 shown in Fig.8, the visual markers allowing for proper relative positioning of the positioning guide and the assembly 100 are complementary shapes allowing for the insertion of a foot arranged at the base of each of the arms of the positioning guide into a cavity of complementary shape to the foot arranged at the base of the positive mold 110.

[0058] Advantageously, when the placement guide 112 is assembled against or near the positive mold 110 and positioned according to the predetermined reference position from the 3D model, and the attachment 116 is fixed to the central part of the placement guide 112, a practitioner or operator can proceed to cement the attachment 116 to a prosthesis fabricated on the positive mold 110. This cementing can be achieved using an adhesive, cement, or any other product, element, or assembly of fasteners. Once the attachment 116 has been cemented to the positive mold 110 (or to an interface envelope affixed to the positive mold), the dental technician or operator can disassemble the attachment 116 from the placement guide 112 and apply to the positive mold 110 the material used to continue fabricating the socket of the prosthesis.This material is then deposited in the form of a layer covering the positive mold 110 and enclosing the attachment 116 intended to receive an end of an artificial limb or an intermediate attachment element of an artificial limb configured to be assembled on the attachment 116.

[0059] Advantageously, presenting the set 100 in kit form makes it easier to transport.

[0060] According to one embodiment, the positive mold 110 and the placement guide 112 of the attachment 116 are delivered in the form of digital files comprising data respectively representative of the shapes (or profiles, or volumes, in reference to an orthonormal reference frame) of each and allowing a prosthetist practitioner or an operator to manufacture them himself with equipment programmed from these digital files, before using them for the manufacture of a prosthesis.

[0061] According to one embodiment, the positive mold is delivered in the form of a digital file comprising data representative of its shape (or profile, or volume with reference to a reference orthonormal frame) and the positioning guide 112 of the attachment 116 is delivered in the form of a digital file comprising data established for the configuration of a robot or an articulated arm, according to a predetermined position, with reference to the reference orthonormal frame used for the manufacture of the positive mold, allowing, in the end, the use of this robot or this articulated arm, equipped with a gripping element of the attachment 116, to serve as a positioning guide equivalent to the positioning guide made of a material and comprising one or more arms, at least one of which carries a visual reference.

[0062] Figure 9 is a diagram illustrating a method for assisting in the manufacture of a prosthetic limb according to one embodiment, more precisely in the form of a method for assisting in the manufacture of a prosthetic limb socket. Step S0 is an initial preparation step for the socket manufacturing method, at the end of which all the necessary components are made available to a prosthetist or an operator working under the supervision of a prosthetist. Thus, at the end of the initial step S0, the positive mold 110 has been designed and manufactured (e.g., 3D printed or machined, or both) from the digitally modified three-dimensional model 44 under the control of the control unit 41.Similarly, the positioning guide 112 was automatically designed from a three-dimensional digital model of the positive mold 110, determining the number and dimensions of the arm(s) of the positioning guide 112, as well as their precise shape, based in particular on the attachment model 116 designed for this purpose or selected from a catalog of attachment parts for prostheses. Thus, at the end of the initial preparatory step S0, the prosthetist or operator has the complete manufacturing aid 100, designed from the digital model of the inside of a temporary or anterior prosthesis of the wearer, and which has been provided to them (for example, by delivery to their practice).During step S1, the positive mold 100 is placed on a reference plane or base, providing stable and precise positioning in space. The positioning guide 112 can also be used as a reference point to establish a common spatial reference frame (or common reference space). In step S2, the positioning guide is then positioned along or around the positive mold 110 so that the visual marker(s) on the positive mold 110 and the positioning guide 112 coincide. In step S3, the fastener 116 is positioned and fixed against the central portion 112m of the positioning guide 112, placing it between the central portion 112m and the top of the positive mold 110 at a predetermined distance, or possibly tangentially flush with the surface of the positive mold 110 or against the mold.In one embodiment, the attachment is secured using a screw or bolt, or a set of screws or bolts. A step S4 then takes place, for example, using a strong adhesive or cement, for sealing the attachment 116 to the positive mold 110. In another embodiment, the process then includes, after sealing the attachment 116 to the positive mold 110, a drying step for the adhesive or cement, followed by a disassembly step of the attachment 116 and the central or end portion of the positioning guide 112, for example, by removing any screws used. The mold to which the attachment 116 is then attached is ready to be coated with a material that will dry to create a prosthetic socket for which the attachment point of an artificial limb is optimized, although the socket is manufactured manually in this case.

[0063] In one variant, the positioning guide 112 is an articulated arm or robot whose position is programmed to implement the positioning guide 112, i.e., by aligning its position with the position of the positive mold 110 in order to position the fastener 116 at the predetermined location when the fastener 116 is held by a terminal gripping element of the articulated arm or robot, optionally precisely positioned by an element acting as a visual alignment guide. The articulated arm, or robot, thus programmed, performs the same positioning guide function as the previously described positioning guide 112. To achieve this, a work surface S is used that conforms to a single spatial reference frame for both the robot and the positioning of the positive mold 110.In this case, any point of a terminal gripping element or tool of the attachment 116, arranged at the end of the articulated arm or robot, operates the function of a reference point, visual or not, whose programmed position is determined with respect to a reference point of the positive mold 110 or to a reference position of the positive mold 110 on the working surface S.

[0064] Fig. 11 illustrates a design and manufacturing process for assembly 100 of a socket manufacturing aid according to one embodiment.

[0065] An initial step S0' is an initial preparation step at the end of which the provisional socket or an anterior socket 2 has been digitized using the three-dimensional modeling system illustrated in Fig. 2 or a similar system. During a step S1', the control unit 41 determines a three-dimensional volume with a shape complementary to the inner surface of the socket 2, inserting modifications as needed to increase wearer comfort and / or the mechanical characteristics of the prosthesis to be produced (range of motion, load absorption, etc.). In addition, the reference point PI for positioning the attachment 116 is also determined with respect to the preliminary settings established as described in relation to Fig. 1. This three-dimensional volume is then used by the control unit 41 to determine another volume for defining the positive mold 110, during a step S2'.Then the shape and dimensions of the placement guide 112 are determined during a step S3' by the control unit 41 from the modeled volume of the positive mold 110, the chosen attachment model 116 and possibly the material chosen to make the prosthesis socket since this choice has an impact on the strength of the socket and therefore on its thickness.

[0066] The dimensions of the positioning guide 112 are calculated based on the dimensions of the positive mold 110, the dimensions of the chosen fastener 116, and the desired thickness of the socket, which depends on the required mechanical characteristics. Finally, the positive mold 110 and the positioning guide are manufactured, during step S4', by a 3D printer, a machining center, or a combination of machining and additive manufacturing using one or more dedicated machines.

[0067] The use of the prosthesis manufacturing aid kit 100 in a manufacturing process such as that described in relation to Fig. 9 advantageously allows for very precise alignment and positioning of the artificial limb attachment. 3D printing the internal shape of the prosthesis, defined here as the positive mold 110, and the placement guide 112 greatly simplifies and accelerates the manufacturing process. Furthermore, the system can be easily modified to accommodate various prosthesis configurations.

[0068] Fig. 10 schematically illustrates an example of the internal architecture of the 4L control unit. For illustrative purposes, Fig. 10 illustrates an internal arrangement of the 4L control unit. It should be noted that the architecture shown could also be used as the internal architecture of the internal systems of the distance measuring device 42 or as the internal architecture of the 3D printing device 45. According to the example of hardware architecture shown in Fig.10, the control unit 41 then comprises, connected by a communication bus 419: a processor or CPU (“Central Processing Unit”) 411; a RAM (“Random Access Memory”) 412; a ROM (“Read Only Memory”) 413; a storage unit such as a hard disk drive (or a storage media reader, such as an SD card reader (“Secure Digital”) 414; at least one communication interface 415 allowing the control unit 41 to communicate with other devices to which it is connected, such as the distance measuring device 42 or the 3D printing device 45 or internal devices such as a screen, a keyboard, etc.

[0069] According to one embodiment, the communication interface 415 is also configured for the control of a user interface configured for the supervision of the manufacturing operations of a final socket using the system 400 and according to the process described and its variants described.

[0070] The processor 411 is capable of executing instructions loaded into RAM 412 from ROM 413, external memory (not shown), storage media (such as an SD card), or a communication network. When the control unit 41 is powered on, the processor 411 can read instructions from RAM 412 and execute them. These instructions form a computer program that causes the processor 411 to implement all or part of a process described in relation to Fig. 11, or variations thereof.

[0071] All or part of the processes described in relation to Fig. 11, or their described variants, can be implemented in software form by executing a set of instructions by a programmable machine, for example a DSP (Digital Signal Processor) or a microcontroller, or implemented in hardware form by a dedicated machine or component, for example an FPGA (Field-Programmable Gate Array) or an ASIC (Application-Specific Integrated Circuit). In general, the control unit 41 comprises electronic circuitry configured to implement the described processes in relation to itself.Obviously, the control unit 41 also includes all the elements usually present in a system comprising a digital core operating control unit functions and its peripherals, such as, a power supply circuit, a power supply monitoring circuit, one or more clock circuits, a reset circuit, input / output ports, interrupt inputs, bus drivers, this list being non-exhaustive.

[0072] According to an alternative embodiment illustrated in Fig. 12, the prosthesis manufacturing aid assembly 100 comprises a positive mold 110 having a surface shape complementary or substantially complementary to an internal surface of a limb prosthesis socket and having at least one first visual reference mark 110 allowing precise and reference positioning of the positive mold 110 relative to a reference working surface S on which the positive mold 110 is positioned and held, and the positioning guide 112 is an articulated arm, for example a robot arm forming a branch 112a, positioned in space with reference to said working surface S, and whose actuator operates, in a programmed position, a second reference mark 112n intended to coincide with a determined position of the positive mold 110 established with reference to said first visual reference mark 110.The robot arm, forming the branch 112a of the positioning guide 112, further carries a holding and positioning element 112m within the space of a mechanical attachment 116 configured to allow the fixation of an artificial limb onto a surface of a material applied to the positive mold 110 in order to form a socket for the prosthetic limb. According to the described embodiment, a visual marker SA and a positive mold support 110g are used to define a reference position of the positive mold 110 on the working surface S. According to an embodiment illustrated by way of non-limiting example, the element 110g is a vertical holding axis inserted into a cavity or machining of the positive mold 110, and the markers 110g and SA are used to correctly orient the positive mold 110 around the vertical axis defined by the element 110g. This makes it possible to determine a reference position of the positive mold 110.determined from a 3D model in a spatial reference frame. According to this same embodiment, the reference frame 112n is used to normally position the attachment 116 in a gripping actuator of the articulated arm (for example, a rod intended to be inserted into a bore of the attachment 116). Obviously, this example is not limiting, and the reference frame 112n can be any element participating in the gripping function of the attachment 116 by the articulated arm or robot 112, such as to determine a relative position of the attachment 116 and the positive mold 110 in order to position the attachment on the prosthesis to be made on the positive mold.

[0073] The invention is not limited to the examples and embodiments described, but more generally to any set of aids for the manual manufacture of a prosthesis from a positive mold using a guide for positioning an attachment of an artificial limb, the positioning guide being designed and then manufactured from a 3D model of the inner surface of a socket or being a robot programmed from this 3D model, as well as to any manufacturing process using a positive mold and such a positioning guide to position such an attachment.

Claims

23 DEMANDS 1) Assembly (100) of aids for the manufacture of a prosthetic limb (F), said assembly comprising: - a positive mold (110) having a surface shape complementary or substantially complementary to an internal surface of a first socket (2) of a prosthesis (1) of a limb and having at least one first visual landmark, (H On), - a positioning guide (112) comprising at least one arm (112a) and one end of which has a second marker (112n) intended to coincide with said first visual marker (HOn), or with a position of said positive mold (110) established with reference to said first visual marker (HOn), said arm (112a) of said guide (112) further carrying a retaining and positioning element in space (112m) of a mechanical attachment (116) configured to allow the fixing of an artificial limb (3) on a surface of a material applied to said positive mold (110) in order to form a second socket of said prosthetic limb. 2) Assembly (100) for the manufacture of a prosthetic limb according to claim 1, said assembly comprising at least four branches (112a, 112b, 112c, 112d) between which is arranged said support and positioning element (112s) and of which one or more branch ends (112a, 112b, 112c, 112d) have said support and positioning element (112s), and the second marker (112n) being a visual marker. 3) Assembly (100) of aid in the manufacture of a prosthetic limb according to one of claims 1 and 2, further comprising a ring (114) configured to hold in position and stabilize said guide (112) against said positive mold (110). 4) Method for manufacturing a prosthetic limb (1'), the method being characterized in that it comprises the use of an assembly (100) for manufacturing a prosthetic limb (F) according to one of claims 1 to 3 and in that it comprises the steps: placing (11) said positive mold (110) of said assembly (100) on a reference surface, position (S2) the positioning guide (112) of said assembly (100) so that the part of said mold (110) having said first visual mark (HOn) is in contact with the part of said guide (112) having said second visual mark (112n), said first (HOn) and second (112n) visual marks (HOn, 112n) being arranged opposite each other or coinciding with each other, assemble (S3) a fastener (116) on said holding and positioning element (112s) in the space of said positioning guide (112), perform a sealing (S4) of said fastener (116) and of a surface or envelope of said positive mold arranged opposite said fastener (116). 5) Method of manufacturing a prosthetic limb (1') according to claim 4, further comprising depositing a layer of material around said positive mold (110), the deposited material sealing said attachment (116) on said positive mold (110) to form said second socket (2') of prosthesis (1') equipped with an attachment (116) configured for the fixation of an artificial limb (3). 6) Method of manufacturing a prosthetic limb (1') according to any one of claims 4 and 5, the method further comprising a preliminary manufacturing step by 3D printing, machining or laser cutting said positive mold (110) from a 3D digital model obtained by modeling an inner surface of said first socket (2) of prosthesis (1). 7) Method of manufacturing a prosthesis (1') of a limb according to any one of claims 4 and 5, the method further comprising prior manufacturing by 3D printing, machining or laser cutting of said placement guide (112) from a 3D digital model (44) obtained by modeling an inner surface of said first prosthesis socket (2). 8) Method of manufacturing a prosthetic limb according to any one of claims 4 and 5, the method further comprising prior manufacturing by 3D printing, machining or laser cutting of said positive mold (110) and said placement guide (112) from a 3D digital model obtained by modeling an inner surface of said first socket (2) of prosthesis (1), said positive mold (110) and placement guide (112) being manufactured in the same element and being separable by means of pre-cuts or breakable parts. 9) A method for manufacturing an assembly (100) of a manufacturing aid according to any one of claims 1 to 3, said method comprising the steps of: obtaining a first 3D digital model (44), representative of the inner surface of said first socket (2), by digitizing the inner surface of said first socket (2), with reference to a spatial reference frame (10) comprising at least one reference point (PI), determining a second 3D digital model, representative of the shape of said positive mold (110) of said second socket (2'), from the first 3D digital model (44), determining a third 3D digital model, representative of the shape of said positioning guide (112), from the second 3D digital model, and manufacturing by 3D printing, laser cutting or machining, of the positive mold (110) or of said positioning guide (112). 10) Method of manufacturing an assembly (100) of manufacturing aid according to any one of claims 1 to 3, said method further comprising a step of determining a fourth 3D digital model, representative of the shape of said band (114). 11) Product computer program comprising program code instructions to execute the steps of the process according to any one of claims 9 and 10 when said program is executed by a processor. 12) Information storage medium comprising a computer program product according to claim 11.

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