A personalized wrist brace based on biomechanical analysis and a design method thereof

Abstract

The application discloses a kind of individualized wrist brace based on biomechanical analysis and its design method, belong to medical apparatus field. Including: patient data collection, brace original design, brace structure optimization, brace detailed design, brace production and inspection. It is based on the complete brace generated by the three-dimensional model of the affected part reconstructed by patient CT scanning, eliminates pressure point and friction point;Then the local bone muscle system of patient is simulated by computer, according to the statics and thermodynamics results obtained by finite element analysis, lattice is generated on the complete brace, under the premise of not affecting the wearing of patient, the negative influence of joint on the rigidity of single direction of brace is reduced;Hollow out brace is provided with semicircular guide groove, C-shaped guide groove and accessory base;The brace is locked by pulling one or several steel cables, and the locking, fine adjustment, disengagement and removal of the brace are realized after wearing. It can be widely used in the design and manufacturing field of individualized custom wrist brace.

Description

Technical Field

[0001] This invention belongs to the field of medical devices, and in particular relates to a personalized wrist fixation brace generated based on the patient's own three-dimensional shape data and the biomechanical analysis results of the musculoskeletal system, as well as its design, manufacturing and testing methods. Background Technology

[0002] Distal radius and ulna fractures are among the most common fractures in clinical practice, accounting for up to one-sixth of all fracture cases. Reduction and fixation with traditional external wrist fixation braces made of plaster casts, low-temperature thermoplastic plates, and high-temperature thermoplastic plates are the routine treatment methods for these fractures.

[0003] The invention patent with authorization announcement date of August 21, 2013, and authorization announcement number CN 102068060 B, discloses a "dynamic wrist brace" consisting of a rigid brace that diverts stress and a soft inner pad that cushions stress. The rigid brace includes a palm brace fixed to the hand and a forearm brace fixed to the forearm. The palm brace and forearm brace are adjacent at the wrist joint and connected by the soft inner pad, but do not contact each other when the wrist joint is in a neutral position. The soft inner pad is bonded or sewn to the inner surface of the rigid brace. This patent document argues that, in order to create a wrist brace suitable for daily use that maintains wrist flexibility while effectively reducing the impact of external forces on the wrist joints, the wrist brace must be designed to be flexibly connected between the wrist and forearm protection systems. Maintaining wrist flexibility, comfort, and convenience of use will improve user compliance and increase usage, thereby maximizing its protective function. However, the best way to reduce the impact on the wrist joint is to use hard materials to divert the external force acting on the hand to the forearm and use soft materials to absorb the external force. This requires that the hard protective gear fixed to the hand and the hard protective gear fixed to the forearm make a real connection and force transfer at the moment the hand hits the ground (see paragraphs

[0004] to

[0009] of its instruction manual).

[0004] Clearly, the focus of the above technical solution is to provide a wrist brace (also known as a wrist protection device) suitable for daily use that can maintain wrist flexibility and effectively reduce the impact of external forces on the wrist joints. It does not address the issue of external fixation after distal radius and ulna fractures. Although the concept of "protecting the distal radius and ulna" is mentioned, it is only addressed under the premise that "when the hand lands in a palmar flexion position, ... the impact force on the back of the hand is transmitted through the palm guard to the forearm guard and dispersed throughout the coverage area of ​​the dynamic wrist brace, where it is absorbed by the underlying soft tissue." It is not applicable to the external fixation of the wrist after distal radius and ulna fractures.

[0005] A utility model patent with authorization announcement date of January 1, 2021, and authorization announcement number CN 212261640 U, ​​discloses a "powered brace for promoting the recovery of forearm rotation function," including a wrist brace and an elbow brace that can be assembled along the patient's forearm. The wrist brace is generally semi-tubular with a thumb placement opening at the front end, and the elbow brace is generally a bent semi-tubular structure. The assembled ends of the wrist brace and the elbow brace are connected by an elastic element. This utility model can fix the wrist joint while providing power for forearm rotation training for forearm pronation or supination dysfunction, which is beneficial to improving the auxiliary training effect of forearm pronation or supination function recovery. The key point of the design concept of this technical solution is "while fixing the wrist joint, it can provide power for forearm rotation training for forearm pronation or supination dysfunction" (see paragraph

[0003] of its specification). Therefore, it only pays attention to "fixing the wrist joint" and does not give much consideration to the problem of external fixation of the wrist after distal radius and ulna fractures.

[0006] In addition, various traditional wrist external fixation braces are still widely used. However, these traditional wrist external fixation braces rely heavily on inefficient manual operation and have inherent defects in terms of fit and comfort. For example, it is difficult to keep the affected area clean and dry; the brace has poor breathability, often causing itching, sweating, odor, and rashes; plaster braces are very heavy, seriously affecting the patient's daily life; the fit is poor, with pressure points and friction areas, which can easily cause redness, swelling, and numbness; they are difficult to put on and take off; they require a lot of manual operation during production; the maker needs a certain amount of experience, and rework and repeated fine adjustments are often required.

[0007] Therefore, further improvements to existing technologies are needed. Summary of the Invention

[0008] The technical problem this invention aims to solve is to provide a personalized wrist brace based on biomechanical analysis and its design method. While ensuring sufficient mechanical strength to guarantee therapeutic efficacy, it improves the fit between the brace and the affected area and enhances wearing comfort. A complete brace is generated based on a three-dimensional model of the affected area reconstructed from the patient's CT scan to ensure fit and eliminate pressure and friction points. Then, the patient's local musculoskeletal system is simulated by computer, and lattice perforations are generated on the complete brace based on the static and thermodynamic results (static and thermal fields) obtained from finite element analysis. The shape of the perforated portion is generated by a computer algorithm based on the static and thermal fields of the affected area surface. Areas with high stress concentration have denser lattice perforations and smaller perforation areas to improve strength and eliminate stress concentration. At the midpoint, in areas with lower stress and higher temperature, the lattice is sparse and the perforated area is large to reduce heat accumulation and structural weight; to minimize the negative impact of seams on the unidirectional stiffness of the brace without affecting patient wear; semi-circular guide grooves, C-shaped guide grooves, and accessory bases need to be added to the perforated brace; the brace is locked after wear by pulling one or more steel cables with a lubricated protective coating to lock the brace body; the pulling mechanism can be adjusted by turning the knob to adjust the tension of the steel cable to achieve fine adjustment of the brace tightness, and can also reliably lock the length of the steel cable to fix the brace, and can also release and remove the brace by loosening the steel cable.

[0009] The technical solution of this invention is: to provide a personalized wrist brace based on biomechanical analysis and its design method, characterized in that the design of the wrist brace includes the following steps:

[0010] 1) S1, Patient Data Collection:

[0011] Read the CT data of the patient's affected area, extract the data of the skin, bone and soft tissue parts of the affected area from the finger to the elbow joint, and reconstruct them into three-dimensional models for subsequent generation of the original design of the brace;

[0012] 2) S2, Original design of the brace:

[0013] The affected skin portion obtained in step S1 is processed to generate a complete original design scheme for the brace without cutouts or segments, which will be used for subsequent optimization of the brace structure.

[0014] 3) S3, Support Structure Optimization:

[0015] The stress and heat distribution of the brace were simulated when the patient wore it. Computer simulation was performed, and based on the static and thermodynamic results obtained from finite element analysis, lattice cutouts were generated on the complete brace.

[0016] 4) S4, Detailed design of the support:

[0017] The lattice cutout obtained in step S3 is divided into double helix slices, and edging is added to the edges of the two slices of the cutout support. Then, design details including semi-circular guide grooves, C-shaped guide grooves and accessory bases are added to make the lattice cutout a cutout support design scheme.

[0018] 5) S5, Bracing fabrication and inspection:

[0019] The hollowed-out brace design scheme, refined in step S4, was prototyped and produced, and then tested after assembly.

[0020] Specifically, the collection of S1 patient data includes the following sub-steps:

[0021] S11. Reading Data: Use open-source or commercial software to read the patient's CT data;

[0022] S12. Create Region of Interest: Create a region of interest (VOI) for the fracture site and hide the rest.

[0023] S13, Adjusting the threshold: A skin mask is created in the VOI by adjusting the threshold;

[0024] S14. Modify the selection: Use tools including the brush and eraser to finely modify the mask and ensure that all skin is correctly selected;

[0025] S15. Reconstruction Calculation: Perform three-dimensional reconstruction calculation;

[0026] S16. Correct the rebuild error;

[0027] S17. Export the reconstruction results.

[0028] Specifically, the original design of the S2 brace includes the following sub-steps:

[0029] S21. Establish a suitable selection area: Establish a suitable selection area for the affected skin area;

[0030] S22, Offset: Perform an offset operation on the appropriate selection area;

[0031] S23, Smoothing and Shaping: Use the smoothing command to eliminate anatomical features, including blood vessels on the back of the hand and palm lines, in the offset selected area; then establish a suitable selected area on the three-dimensional shape of the ulnar styloid process and radial styloid process, offset it outward by 1mm to 5mm to prevent the formation of pressure points.

[0032] S24. Shelling: Shell the smoothed selected area outward by 1mm to 10mm to form a complete wrist brace. The shelling thickness is the brace thickness of the final product.

[0033] S25. Repair Model: Inspect and repair the original design of the support after shelling to ensure that the three-dimensional model is free from errors, including incorrect normal direction, broken surfaces, discrete surfaces, holes, and overlapping surfaces.

[0034] Furthermore, in the appropriate selection area in the S21 sub-step, the distal boundary of the selection area is the middle section of the second phalanx, and at least one-third of the length of the second phalanx should be retained; the remaining four fingers are cut to the middle section of the second to fifth metacarpal bodies, at least half the length of the metacarpal body should be retained, and at most should not exceed the bottom edge of the metacarpal head.

[0035] The proximal boundary of the selected area is the middle segment of the radius and ulna shafts, and should be no less than one-third of the length of the radius and ulna, and no longer than the bottom edge of the radial head.

[0036] Specifically, the optimization of the S3 support structure includes the following sub-steps:

[0037] S31. Finite element preprocessing: Import the three-dimensional reconstructed skin, bone and soft tissue models of the affected area into the finite element analysis software, perform mesh generation and assign various physical properties to the human tissues to which they belong; in the finite element analysis software, constrain the relationship between the patient's hand model and the complete model of the brace, including contact and friction, and then add loads to simulate one or more common hand movements.

[0038] S32. Finite Element Analysis: Output and save the stress distribution on the surface of the complete brace under one or more common hand movements; simulate the heat distribution of the hand model and the complete brace model when the patient wears the brace, and output and save the temperature distribution on the surface of the complete brace.

[0039] S33. Generating lattice cutouts: The finite element results are converted into discrete points on the surface of the complete support, then into Thiessen polygons, and finally into lattice cutouts of the support.

[0040] 6. The personalized wrist brace based on biomechanical analysis and its design method according to claim 5, characterized in that in the S31 sub-step, one or more common hand movements include at least wrist extension, flexion and rotation;

[0041] In the S33 sub-step, the volume of the lattice cutout should not exceed 90% of the volume of the complete support, and at the same time, the volume of the lattice cutout should not be less than 50% of the volume of the complete support.

[0042] Specifically, the detailed design of the S4 support includes the following sub-steps:

[0043] S41, Double Helix Segmentation: Using a 360° twisted plane, the lattice is hollowed out and divided into two double helix segments. The thickness of the plane is 1mm to 5mm, and the thickness of the plane is the distance between the two segments after division.

[0044] S42. Edge binding: Bind the edges of the two hollow support pieces, with a binding width of 1-20mm.

[0045] S43. Add semi-circular guide grooves: Add at least two semi-circular guide grooves to the joint of the two spiral segments to guide the two support segments to move in a preset direction during support installation or fine adjustment.

[0046] S44. Add C-shaped guide grooves: Add C-shaped guide grooves in pairs on both sides of the joint of the two spiral segments to restrict the movement of the steel cable and ensure that the steel cable will not slip when the locking mechanism pulls it.

[0047] S45. Add accessory base: The accessory base is used to install one or more locking mechanisms; a steel cable starts from the locking mechanism, crosses back and forth through the C-shaped guide grooves on both sides of one or two joints, and finally returns to the same locking mechanism; the steel cable and the locking mechanism together form a fixing mechanism to fix the support; the tension of the steel cable can be adjusted by turning the knob to achieve fine adjustment of the support tightness, which can reliably lock the length of the steel cable to fix the support, and the support can also be released and removed by loosening the steel cable.

[0048] Specifically, the manufacturing and inspection of the S5 brace includes the following sub-steps:

[0049] S51. Additive manufacturing: The hollowed-out wrist brace is made using additive manufacturing.

[0050] S52. Post-processing: The hollowed-out wrist brace is subjected to post-processing operations including removing residual powder, polishing, cleaning, removing residual liquid, secondary curing, and removing the support structure.

[0051] S53. Assembly: Use adhesive or riveting to fix the locking mechanism to the main body of the support. Pass the steel cable through the C-shaped guide groove in sequence and connect it to the locking mechanism to complete the assembly.

[0052] S54. Trial Wear Test: The device is delivered to the patient for trial wear, and patient feedback is collected through methods such as verbal description, questionnaires, and interviews, which will serve as a reference for future improvements.

[0053] The technical solution of the present invention also provides a personalized wrist brace manufactured according to the above-mentioned biomechanical analysis-based design method, characterized in that:

[0054] The personalized wrist brace is an external fixation brace for the wrist generated based on the patient's own three-dimensional shape data and the biomechanical analysis results of the musculoskeletal system, and produced using additive manufacturing.

[0055] The main structure of the personalized wrist brace consists of two pieces: a main piece and a secondary piece.

[0056] The main body and the auxiliary body are made by cutting the main body of the wrist brace using a double-helix segmentation method;

[0057] A chimney-like structure is provided on the main body of the film, through which the patient's thumb can pass, so that the main body of the film can be fixed to the patient's wrist.

[0058] Two strip-shaped spiral connecting seams are provided between the main body and the sub-body;

[0059] At the same time, at least two semi-circular guide grooves are provided between the main body and the auxiliary body to guide the two support bodies to move in a preset direction during support installation or fine adjustment, so as to avoid misalignment and slippage.

[0060] On both sides of the joint between the main body and the sub-body, several C-shaped guide grooves are provided in pairs. These C-shaped guide grooves allow one or more steel cables to pass through, thereby restricting the movement of the steel cables and ensuring that the steel cables will not slip when pulled by the locking mechanism.

[0061] At least one locking mechanism is provided on the main body or the sub-body;

[0062] A knob for adjusting the length of the steel cable is provided on the locking mechanism; rotating the knob can adjust the tension of the steel cable, realize the fine adjustment of the tightness of the support, and fix, release and remove the support.

[0063] One or more steel cables are installed between the main body and the sub-body. The steel cables start from the locking mechanism, cross and go back and forth through the C-shaped guide grooves on both sides of one or two joints, and finally return to the same locking mechanism.

[0064] The steel cable and locking mechanism together form a fixing mechanism used to fix the main body and the sub-body;

[0065] A lattice-like perforated structure is provided on the main and secondary slices; this lattice is generated based on the patient's own three-dimensional shape data and the results of biomechanical analysis of the musculoskeletal system.

[0066] Furthermore, the surface of the steel cable is provided with a lubricating coating;

[0067] In areas of stress concentration on the patient's skin surface, the dense lattice provides high mechanical strength, preventing the brace from breaking.

[0068] In areas of the patient's skin surface where stress is dispersed, the lattice is sparse, resulting in low mechanical strength and material savings.

[0069] In areas of the patient's skin surface where heat accumulation is severe, the sparse lattice provides strong heat dissipation, preventing the patient from feeling stuffy when wearing it.

[0070] The main and auxiliary film bodies are connected to the patient's wrist in the following manner:

[0071] After the patient's thumb passes through the chimney-shaped structure on the main body, the tail of the main body swings along the direction of the patient's forearm, thus completing the wrapping of the main body around the patient's entire wrist without the patient having to move their hand. This helps reduce pain during wearing and eliminates the possibility of loss of fracture reduction due to large wrist movements during wearing.

[0072] When wearing the accessory lens, it can be directly placed on the patient's wrist. With a slight rotation and swing, the semi-circular guide groove on the accessory lens can be aligned with the corresponding groove on the main lens.

[0073] By pulling one or more steel cables, the main and auxiliary plates of the brace are locked, thus achieving the locking of the brace after it is put on.

[0074] By turning the knob on the locking mechanism, the tension of the steel cable can be adjusted to achieve fine-tuning of the brace's tightness. The length of the steel cable can be reliably locked to fix the brace, and the brace can also be released and removed by loosening the steel cable.

[0075] Compared with the prior art, the advantages of the present invention are:

[0076] 1. The wrist brace described in this invention generates the complete shape of the brace based on the three-dimensional model of the affected area reconstructed from the patient's CT scan. While ensuring that the wrist brace has sufficient mechanical strength to guarantee the therapeutic effect, it improves the matching degree between the brace and the affected area and the comfort when wearing it. While having a matching degree with the affected area, it also eliminates pressure points and friction points, avoiding redness and swelling of the skin and numbness of the affected area.

[0077] 2. In the technical solution of the present invention, the shape of the hollow part is generated by computer algorithm according to the static field and thermal field of the affected area surface. The area with high stress concentration has dense lattice and small hollow area to improve strength and eliminate stress concentration points. The area with low stress and high temperature has sparse lattice and large hollow area to reduce heat accumulation and reduce structural weight. Without affecting the patient's wearing, the negative impact of seams on the unidirectional stiffness of the brace is reduced.

[0078] 3. The wrist brace described in the technical solution of the present invention can be locked after the brace is worn by pulling one or more steel cables. The tension of the steel cables can be adjusted by turning the knob to fine-tune the tightness of the brace. The length of the steel cables can also be reliably locked to fix the brace. Alternatively, the brace can be released and removed by loosening the steel cables.

[0079] 4. The main body and the secondary body of the wrist brace are formed by additive manufacturing using waterproof polymer. Patients can still shower and clean the brace with neutral detergent while wearing it, making it easy to keep clean.

[0080] 5. The main structure of the wrist brace has a lot of openwork, which makes it highly breathable and keeps the area in contact with the patient's skin dry, avoiding problems such as itching, sweating, odor, and rashes when the patient wears it;

[0081] 6. The wrist brace is designed with computer assistance, resulting in high structural efficiency and full utilization of materials. This allows the weight of the brace to be kept to a very low level without compromising its mechanical properties, and it does not interfere with the patient's daily life when worn.

[0082] 7. The main structure of the wrist brace adopts a double-helix segmented structure, which can be easily worn by patients without moving their hands and wrists. This not only reduces the pain when wearing the brace, but also avoids the possibility of loss of fracture reduction due to large movements of the wrist when wearing it.

[0083] 8. Semicircular guide grooves are provided on the edges of the main and auxiliary plates of the wrist brace to limit the relative displacement between the main and auxiliary plates. Attached Figure Description

[0084] Figure 1 This is a block diagram illustrating the personalized wrist brace design method of the present invention;

[0085] Figure 2 This is a schematic diagram of three-dimensional reconstruction during the patient data collection process of this invention;

[0086] Figure 3 This is a block diagram illustrating the original design method of the brace of the present invention;

[0087] Figure 4 This is a schematic diagram of the result after the preprocessing operation of the present invention;

[0088] Figure 5 This is a schematic diagram of the stress distribution on the surface of the complete support of the present invention;

[0089] Figure 6 This is a schematic diagram of the heat distribution on the surface of the complete support of the present invention;

[0090] Figure 7This is a schematic diagram of the Thiessen polygon generated based on the finite element analysis results of this invention.

[0091] Figure 8 This is a schematic diagram of the lattice hollowing generated according to the finite element analysis results of the present invention;

[0092] Figure 9 This is a schematic diagram illustrating the double-helix segmentation and edge-binding of the lattice hollowing in this invention;

[0093] Figure 10 A schematic diagram of the accessory base for this invention, including the addition of a semi-circular guide groove, a C-shaped guide groove, and an accessory base.

[0094] Figure 11 This is a front structural schematic diagram of an embodiment of the personalized wrist brace of the present invention;

[0095] Figure 12 This is a schematic diagram of the back structure of an embodiment of the personalized wrist brace of the present invention;

[0096] Figure 13 This is a schematic diagram illustrating the connection between the main body of the wrist brace of the present invention and the patient's wrist;

[0097] Figure 14 This is a schematic diagram illustrating the connection between the accessory body of the wrist brace of the present invention and the patient's wrist.

[0098] In the image, 21 represents the affected skin; 22 represents the soft tissue; 23 represents the bone; 24 represents the distal boundary of the 3D model; 25 represents the carpal bones; 26 represents the distal radius fracture line; 27 represents the radius and ulna; and 28 represents the proximal boundary of the 3D model.

[0099] 31 is the distal boundary of the 3D model, 32 is the distal boundary of the suitable selection area, 33 is the skin part of the affected area, 34 is the original design of the brace, 35 is the gap between the brace and the skin, 36 is the thickness of the brace, 37 is the proximal boundary of the suitable selection area, and 38 is the proximal boundary of the 3D model.

[0100] 41 shows the skin, bone, and soft tissue model of the affected area; 42 shows the added loads; 43 shows the mesh of the complete brace; and 44 shows the added constraints.

[0101] 51 is a high-stress zone, and 52 is a low-stress zone;

[0102] 61 is the high temperature zone, and 62 is the low temperature zone;

[0103] 71 represents discrete points generated based on the finite element analysis results, and 72 represents Thiessen polygons generated based on the discrete points;

[0104] 81 is a cutout generated along the edge of the Thiessen polygon, 82 is a chamfer at the included angle of the Thiessen polygon, and 83 is a lattice cutout generated based on finite element analysis.

[0105] 91 is the edging, 92 is the gap between the segments, and 93 is the double helix segmentation and the hollow lattice after adding the edging;

[0106] 101 is a semi-circular guide groove, 102 is an accessory base, 103 is a C-shaped guide groove, and 104 is a hollow support.

[0107] 1101 is the main body, 1101a is the tail of the main body, 1102 is the secondary body, 1103 is a chimney-shaped structure, 1104 is a connecting seam, 1105 is a semi-circular guide groove, 1106 is a steel cable, 1107 is a locking mechanism, 1108 is a C-shaped guide groove, 1109 is a lattice cutout, 1110 is the patient's thumb, and 1111 is the patient's wrist. Detailed Implementation

[0108] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0109] The technical solution of this invention, while ensuring that the wrist brace has sufficient mechanical strength to guarantee the therapeutic effect, improves the matching degree between the brace and the affected area and the comfort during wearing. It provides a personalized wrist fixation brace generated based on the patient's own three-dimensional shape data and the biomechanical analysis results of the musculoskeletal system, as well as its design, manufacturing and testing methods.

[0110] The overall concept of this invention is to generate a complete, customized wrist fixation brace (hereinafter referred to as the brace) based on a three-dimensional model of the affected area reconstructed from a patient's CT scan, ensuring a good fit and eliminating pressure and friction points. Then, the patient's local musculoskeletal system is simulated using computer simulation. Based on the static and thermodynamic results (static and thermal fields) obtained from finite element analysis, a lattice of openwork (also called a hollowed-out lattice) is generated on the complete brace. The shape of the openwork is generated according to the static and thermal fields of the affected area surface. Areas with high stress concentration have denser lattice openings and smaller openwork areas to improve strength and eliminate stress concentration points, while areas with lower stress and higher temperature have sparser lattice openings. The openwork area is large to reduce heat accumulation and structural weight; the body of the brace adopts a double-helix segmented structure to reduce the negative impact of seams on the unidirectional stiffness of the brace without affecting the patient's wearing experience; semi-circular guide grooves, C-shaped guide grooves, and accessory bases are added to the openwork brace; the brace is locked after wearing by pulling one or more steel cables with a lubricated protective coating to lock the brace body; the pulling mechanism can adjust the tightness of the brace by turning the knob to adjust the tension of the steel cable, and can also reliably lock the length of the steel cable to fix the brace, and can also release and remove the brace by loosening the steel cable.

[0111] Specifically, the technical solution of the present invention is as follows:

[0112] A flowchart illustrating the design process of a personalized wrist brace based on biomechanical analysis is shown below. Figure 1 As shown.

[0113] This specifically includes the following steps:

[0114] S1. Patient data collection;

[0115] S2, Original design of the brace;

[0116] S3. Optimization of support structure;

[0117] S4. Detailed design of the bracing;

[0118] S5. Bracing fabrication and inspection.

[0119] The S1 patient data collection step includes using open-source or commercial software to read the CT data of the patient's affected area, extracting data of the skin, bone and soft tissue parts of the affected area from the fingers to the elbow joint, and reconstructing them into three-dimensional models for subsequent generation of the original design of the brace.

[0120] In the S1 patient data collection step Figure 2 This is a schematic diagram of the 3D reconstruction method during patient data collection. In the diagram: 21 is the skin of the affected area; 22 is the soft tissue; 23 is the bone; 24 is the distal boundary of the 3D model (metacarpophalangeal joint); 25 is the carpal bones (8 bones); 26 is the distal radius fracture line; 27 is the radius and ulna; 28 is the proximal boundary of the 3D model (proximal radioulnar joint).

[0121] The S1 patient data collection step includes the following sub-steps:

[0122] S11, Read data;

[0123] S12. Establish the region of interest;

[0124] S13, Adjust the threshold;

[0125] S14, Modify the selection area;

[0126] S15, Reconstruction Calculation;

[0127] S16. Correct the rebuild error;

[0128] S17. Export the reconstruction results.

[0129] Sub-step S11 involves reading patient CT data using open-source or commercial software.

[0130] Sub-step S12 creates a volume of interest (VOI) for the fractured limb and hides the rest.

[0131] Sub-step S13 is to establish a skin mask in VOI by adjusting the threshold.

[0132] Sub-step S14 involves using tools such as a brush and eraser to finely modify the mask and ensure that all skin is correctly selected.

[0133] Sub-step S15 is to perform three-dimensional reconstruction calculations.

[0134] Sub-step S16 is to correct and rebuild errors.

[0135] Sub-step S17 is to export the reconstruction results.

[0136] When reconstructing CT data, the affected skin portion should be stored separately as a basis for the shape design of subsequent braces.

[0137] During reconstruction, care should be taken to separate the various metacarpals, phalanges, and radius and ulna of the hand musculoskeletal system and preserve their anatomical details for subsequent finite element analysis and computer simulation. To reduce the workload of reconstruction and the probability of model errors, all eight carpal bones (including: scaphoid, lunate, triquetrum, pisiform, trapezium, trapezium, capitate, and hamate) are treated as a whole, and only their general shape is preserved without separation. During reconstruction, care should be taken to distinguish and preserve the anatomical details of each muscle and ligament, and spring elements are used instead in subsequent finite element analysis.

[0138] Specifically, the S2 brace original design step is completed using open-source or commercial 3D design software. The affected skin portion obtained in step S1 is processed to generate a complete original design scheme for the brace without cutouts or segments, which is used for subsequent brace structure optimization.

[0139] In the S2 patient data collection step Figure 3 This is a schematic diagram of the original design method for the brace.

[0140] In the figure: 31 is the distal boundary of the 3D model (metacarpophalangeal joint); 32 is the distal boundary of the appropriate selection area (middle segment of the second phalanx and middle segments of the second to fifth metacarpal bodies); 33 is the skin portion of the affected area; 34 is the original design of the brace; 35 is the gap between the brace and the skin; 36 is the thickness of the brace; 37 is the proximal boundary of the appropriate selection area (middle segment of the radius and ulna shafts); 38 is the proximal boundary of the 3D model (proximal radioulnar joint).

[0141] Furthermore, the original design steps of the S2 brace include the following sub-steps:

[0142] S21. Establish a suitable selection area;

[0143] S22, Offset;

[0144] S23, Smoothing and Shaping;

[0145] S24, Shelling;

[0146] S25, Repair the model.

[0147] In step S21, a suitable selection area is established for the affected skin. The distal boundary of this selection area is the middle segment of the second phalanx, and at least one-third of the length of the second phalanx should be retained. The remaining four fingers are trimmed to the middle segment of the second to fifth metacarpal bodies, retaining at least half the length of the metacarpal body and at most not exceeding the bottom edge of the metacarpal head. The proximal boundary of this selection area is the middle segment of the ulna and radius shafts, with a minimum length not less than one-third of the length of the ulna and radius and a maximum length not exceeding the bottom edge of the radial head.

[0148] The S22 sub-step involves offsetting the appropriate selection area. The offset distance is equal to the distance between the brace and the patient's skin, and this distance is generally selected as 1mm to 5mm.

[0149] Substep S23 involves using a smoothing command to eliminate anatomical features such as blood vessels and palm prints on the back of the hand, which are unnecessary to be reflected in the subsequent brace, from the offset selected area. These features increase the computational cost of subsequent finite element analysis but have minimal impact on the mechanical properties of the brace and are considered useless details. Subsequently, suitable selected areas are established on the ulnar and radial styloid processes of the 3D shape and offset outward by 1mm to 5mm to prevent the formation of pressure points.

[0150] The S24 sub-step involves removing a 1mm to 10mm shell from the smoothed selected area to form a complete wrist brace. The shell thickness is the final brace thickness, determined based on the required mechanical properties of the affected area.

[0151] The S25 sub-step involves checking and repairing the original design of the support after shell extraction to ensure that the 3D model is free from errors such as incorrect normal direction, breakage, discrete surfaces, holes, and overlapping surfaces.

[0152] Specifically, in the S3 brace structure optimization step, open-source or commercial software is used to perform finite element analysis to simulate the stress and heat distribution of the brace when worn by the patient. Computer simulation is conducted, and based on the static and thermodynamic results (static field and thermal field) obtained from the finite element analysis, a lattice hollow is generated on the complete brace.

[0153] The S3 support structure optimization steps include:

[0154] S31, Finite element preprocessing;

[0155] S32, Finite Element Analysis;

[0156] S33, generating a hollowed-out lattice.

[0157] Sub-step S31 is a preprocessing operation before finite element analysis. The 3D reconstructed models of the affected skin, bones, and soft tissues are imported into the finite element analysis software. Meshing is performed, and the models are assigned various physical properties of the corresponding human tissues, including at least: elastic modulus, Poisson's ratio, temperature, and heat flux. The 3D model of the complete brace is then imported into the finite element analysis software and assigned various physical properties, including at least: elastic modulus, Poisson's ratio, specific heat capacity, and thermal conductivity. Then, in the finite element analysis software, the contact and friction relationships between the patient's hand model and the complete brace model are constrained. Loads are then added to simulate one or more common hand movements, including at least wrist extension, flexion, and rotation.

[0158] In sub-step S31 Figure 4 This is a schematic diagram of the preprocessed result.

[0159] In the figure: 1 is the model of the skin, bone and soft tissue of the affected area; 2 is the added load; 3 is the mesh of the complete brace; 4 is the added constraint condition.

[0160] Sub-step S32 is for finite element analysis and solution, outputting and saving the stress distribution on the surface of the complete support under one or more common actions (e.g., Figure 5 (As shown); In the finite element analysis software, the heat distribution of the patient's hand model and the complete brace model when wearing the brace is simulated, and the temperature distribution of the complete brace surface is output and saved (e.g. Figure 6 (As shown).

[0161] In sub-step S32, the stress distribution on the surface of the complete support is as follows: Figure 5 As shown in the image.

[0162] In the diagram: 51 is the high-stress area; 52 is the low-stress area.

[0163] In sub-step S32, the heat distribution on the surface of the complete brace is as follows: Figure 6 As shown in the figure: 61 is the high temperature zone; 62 is the low temperature zone.

[0164] The S33 sub-step involves using a specific algorithm to generate lattice cutouts on the complete support based on the static and thermodynamic results obtained from the finite element analysis. The algorithm statistically summarizes the finite element analysis results, selects a specific stress and temperature value based on the summary results, and extracts the discrete points corresponding to these values ​​on the surface of the complete support. Subsequently, Thiessen polygons are constructed for these discrete points on the support surface.

[0165] The Thiessen polygon, also known as the von Lonoi diagram, is a set of continuous polygons formed by the perpendicular bisectors of line segments connecting two adjacent points.

[0166] The distance from any point within a Thiessen polygon to the discrete points constituting that polygon is less than the distance to the control points of other polygons. Therefore, in the technical solution of this invention, Thiessen polygons are used to describe the static / thermodynamic properties of discrete points on the surface of a complete support.

[0167] In sub-step S33, the finite element results are converted into discrete points on the surface of the complete support, then into Thiessen polygons, and finally into lattice cutouts of the support. This process saves material consumption as much as possible while ensuring strength and heat dissipation, thereby improving the overall structural efficiency.

[0168] In areas of stress concentration, the discrete points are dense and the Thiessen polygons are dense, resulting in high mechanical strength and preventing brace breakage. In areas of stress dispersion, the discrete points are few and the Thiessen polygons are sparse, resulting in low mechanical strength and saving materials. In areas of severe heat accumulation, the discrete points are few and the Thiessen polygons are sparse, resulting in strong heat dissipation and preventing patients from feeling stuffy when wearing the brace.

[0169] In sub-step S33, the volume of the lattice cutout should not exceed 90% of the volume of the complete support to improve material utilization and thermal comfort, while facilitating observation of the affected area and maintaining cleanliness. At the same time, the volume of the lattice cutout should not be less than 50% of the volume of the complete support to avoid excessively reducing the rigidity of the support and affecting the therapeutic effect. The corners of the lattice cutout should be rounded at the corners of the Tyson polygon with a radius of 0.2mm to 5mm to prevent pressure and friction on the affected area.

[0170] In sub-step S33, the Thiessen polygon generated based on the finite element analysis results is as follows: Figure 7 As shown in the image.

[0171] In the figure, 71 represents discrete points generated based on the finite element analysis results, and 72 represents Thiessen polygons generated based on the discrete points.

[0172] In sub-step S33, lattice cutouts are generated based on the finite element analysis results, such as... Figure 8 As shown in the image.

[0173] In the figure, 81 is the cutout generated along the edge of the Thiessen polygon, 82 is the chamfer of the included corner of the Thiessen polygon, and 83 is the lattice cutout generated based on finite element analysis.

[0174] Specifically, the S4 support refinement design steps involve dividing the lattice hollow obtained in step S3 into double helix slices, adding edging to the edges of the two slices of the hollow support, and then adding design details including semi-circular guide grooves, C-shaped guide grooves, and accessory bases to make the lattice hollow become the hollow support design scheme.

[0175] Specifically, the detailed design steps for the S4 brace include the following sub-steps:

[0176] S41, Double Helix Slicing;

[0177] S42, Binding;

[0178] S43. Add a semi-circular guide groove;

[0179] S44. Add a C-shaped guide groove;

[0180] S45. Add accessory base.

[0181] In substep S41, a 360° twisted plane is used to divide the lattice into two double-helix segments. The thickness of this plane is 1mm to 5mm, and the thickness of the plane is the distance between the two segments after division.

[0182] In sub-step S42, the edges of the two hollowed-out brace panels are edged with a width of 1–20 mm. Adding edge binding can prevent compression of the affected skin and improve the torsional resistance of the brace panels; however, excessively thick edge binding will reduce the brace's heat dissipation capacity and increase its weight.

[0183] In sub-step S43, at least two semi-circular guide grooves are added to the joint of the two spiral segments. The semi-circular guide grooves are used to guide the two support segments to move in a preset direction during support installation or fine adjustment to avoid misalignment and slippage.

[0184] In sub-step S44, C-shaped guide grooves are added in pairs on both sides of the joint between the two spiral segments. These C-shaped guide grooves allow one or more steel cables coated with a lubricating coating to pass through, thereby restricting the movement of the steel cables and ensuring that the steel cables do not slip when pulled by the locking mechanism.

[0185] In sub-step S45, the accessory base is used to install one or more locking mechanisms; a steel cable starts from the locking mechanism, crosses back and forth through the C-shaped guide grooves on both sides of one or two joints, and finally returns to the same locking mechanism; the steel cable and the locking mechanism together form a fixing mechanism to fix the brace; the tension of the steel cable can be adjusted by turning the knob to achieve fine adjustment of the brace tension, and the steel cable length can also be reliably locked to fix the brace, and the brace can also be released and removed by loosening the steel cable.

[0186] In sub-step S42, the lattice cutouts are double-helixed and edge-binding is added, as shown below. Figure 9 As shown in the image.

[0187] In the figure, 91 represents the edging, 92 represents the gap between the segments, and 93 represents the double-helix segmentation and the lattice cutout after adding the edging.

[0188] In sub-step S44, add a semi-circular guide groove, a C-shaped guide groove, and an accessory base as follows: Figure 10 As shown in the image.

[0189] In the diagram: 101 is a semi-circular guide groove, 102 is an accessory base, 103 is a C-shaped guide groove, and 104 is a hollow support.

[0190] Specifically, the S5 brace manufacturing and inspection steps involve prototyping and producing the hollow brace design scheme refined in step S4, followed by assembly and trial wearing inspection.

[0191] The S5 brace fabrication and inspection process includes the following sub-steps:

[0192] S51, Additive manufacturing;

[0193] S52, Post-processing;

[0194] S53, Assembly;

[0195] S54. Trial fitting inspection.

[0196] In sub-step S51, the hollow brace design has a complex shape, making conventional injection molding or cutting methods difficult to implement. Therefore, additive manufacturing must be used. The manufacturing method can be additive manufacturing methods such as laser selective sintering, fused deposition modeling, or photopolymerization. The selected materials are chosen based on the molding method and patient needs, and the selected materials include at least: Nylon 11, Nylon 12, polycaprolactone PCL, polylactic acid PLA, resin, ABS engineering plastics, or other polymers; or, the above materials mixed with carbon fiber / glass fiber as the reinforcing phase can be used.

[0197] In the S52 sub-step, all wrist braces produced need to undergo post-processing, such as removing residual powder, grinding, cleaning, removing residual liquid, secondary curing, or removing support structures.

[0198] In sub-step S53, the locking mechanism is fixed to the support body using adhesive or riveting. The steel cables coated with lubricating coating are then passed through the C-shaped guide grooves and connected to the locking mechanism to complete the assembly.

[0199] In sub-step S54, the personalized wrist brace is delivered to the patient by professionals for trial use, and patient feedback is collected through verbal descriptions, questionnaires, and interviews as a reference for future improvements.

[0200] Example:

[0201] Figure 11 This is a front structural diagram of the personalized wrist brace in this embodiment. Figure 12 This is a schematic diagram of the back structure of the personalized wrist brace in this embodiment.

[0202] This embodiment is a wrist external fixation brace generated based on the patient's own three-dimensional shape data and the results of biomechanical analysis of the musculoskeletal system, and produced using additive manufacturing.

[0203] The main structure of this embodiment consists of two pieces: a main piece 1101 and a secondary piece 1102.

[0204] The main body 1101 has a chimney-shaped structure 1103 that allows the patient's thumb to pass through, thus fixing the main body to the patient's wrist.

[0205] There are two spiral-shaped connecting seams 1104 between the main body and the auxiliary body; at the same time, there are several semi-circular guide grooves 1105 between the main body and the auxiliary body. The semi-circular guide grooves are used to guide the two support bodies to move in a preset direction during the installation or fine adjustment of the support, so as to avoid misalignment and slippage; one or more steel cables 1106 coated with lubricating coating pass between the main body and the auxiliary body. The steel cables start from the locking mechanism 1107, cross and pass back and forth through the C-shaped guide grooves 1108 on both sides of one or two seams, and finally return to the same locking mechanism; the steel cables and the locking mechanism together form a fixing mechanism to fix the support; by turning the knob on the locking mechanism, the tension of the steel cables can be adjusted to achieve fine adjustment of the support tightness, and the length of the steel cables can also be reliably locked to fix the support. The support can also be released and removed by loosening the steel cables.

[0206] The main body and the sub-body have hollowed-out lattices (also known as lattice hollowing) 1109. These lattices are generated based on the patient's own three-dimensional shape data and the results of biomechanical analysis of the musculoskeletal system: the lattice is dense in the areas where stress is concentrated on the patient's skin surface, resulting in high mechanical strength and preventing the brace from breaking; the lattice is sparse in the areas where stress is dispersed on the patient's skin surface, resulting in low mechanical strength and saving materials; and the lattice is sparse in the areas where heat accumulation is severe on the patient's skin surface, resulting in strong heat dissipation and preventing the patient from feeling stuffy when wearing it.

[0207] The way the main body is attached to the patient's wrist is as follows: Figure 13 As shown.

[0208] After the patient's thumb 1110 passes through the chimney-shaped structure 1103 on the main body 1101, the tail 1101a of the main body swings along the direction of the patient's forearm, thus completing the encirclement of the main body around the patient's entire wrist 1111. This process can be completed without the patient moving their hand, which helps reduce pain during wearing and eliminates the possibility of loss of fracture reduction due to large wrist movements during wearing.

[0209] The way the accessory piece is attached to the patient's wrist and the main piece is as follows: Figure 14 As shown.

[0210] When worn, the secondary lens 1102 can be directly placed on the patient's wrist. With a slight rotation and swing, the semi-circular guide groove 1105 on the secondary lens can be aligned with the corresponding groove on the main lens 1101.

[0211] Compared to traditional wrist external fixation braces made of plaster, low-temperature thermoplastic sheets, and high-temperature thermoplastic sheets, the wrist brace of this invention uses waterproof polymers to form its main and secondary bodies through additive manufacturing. Patients can still shower and clean the brace with neutral detergent while wearing it, making it easy to keep clean. The main structure of this wrist brace has numerous perforations, providing excellent breathability and keeping the areas in contact with the patient's skin dry, preventing itching, sweating, odor, and rashes. This wrist brace was designed using computer-aided design. The structure boasts high efficiency and maximizes material utilization, resulting in a minimally sized brace without compromising its mechanical properties, ensuring it doesn't interfere with the patient's daily life. The wrist brace's shape is generated based on the patient's own three-dimensional skin data, achieving a perfect fit while eliminating pressure points and friction areas, preventing redness, swelling, and numbness. The main structure employs a double-helix, segmented design, allowing for easy wearing without requiring the patient to move their hand or wrist, reducing discomfort and minimizing discomfort caused by excessive wrist movement. The wrist brace's main structure employs a double-helix segmented design, avoiding the negative impact of gaps on the overall brace in a specific direction when segmented radially up and down or left and right. This ensures good stability for the patient during flexion, extension, and torsion. The lattice perforations on the surface of the wrist brace are generated based on the static and thermodynamic results obtained from finite element analysis of the patient's own musculoskeletal system. Areas with high stress concentration have denser lattice perforations with smaller areas to improve strength and eliminate stress concentration points, while areas with lower stress and higher temperature have denser lattice perforations. The sparse, openwork design features a large area to reduce heat accumulation and structural weight. Semi-circular guide grooves are provided on the edges of the main and auxiliary panels of the wrist brace to limit relative displacement between them. The wrist brace achieves locking after being worn by pulling one or more steel cables with a lubricated protective coating to secure the main and auxiliary panels. The pulling mechanism on the wrist brace allows for fine-tuning of the brace's tightness by adjusting the steel cable tension using a knob. It reliably locks the steel cable length for brace fixation and allows for release and removal of the brace by loosening the steel cables.

[0212] The technical solution of this invention provides a personalized wrist brace and its design method based on a three-dimensional model of the affected area reconstructed from a patient's CT scan. While ensuring sufficient mechanical strength to guarantee therapeutic efficacy, it improves the fit between the brace and the affected area and enhances wearing comfort. Based on the three-dimensional model of the affected area reconstructed from the patient's CT scan, a complete customized wrist fixation brace is generated to ensure fit and eliminate pressure and friction points. Then, the patient's local musculoskeletal system is simulated by computer, and based on the static and thermodynamic results obtained from finite element analysis, a lattice-like perforation is generated on the complete brace. Corresponding semi-circular guide grooves, C-shaped guide grooves, and accessory bases are provided on the perforated brace body. The entire brace is locked by pulling one or more steel cables, achieving locking after wearing. The pulling mechanism adjusts the tension of the steel cables by turning a knob to fine-tune the brace's tightness, reliably locking the cable length for fixation. The brace can also be released and removed by loosening the steel cables.

[0213] This invention can be widely used in the design and manufacturing of personalized custom wrist braces.

Claims

1. A design method for personalized wrist braces based on biomechanical analysis, characterized by: The design of a wrist brace includes the following steps: 1) S1, Patient Data Collection: Read the CT data of the patient's affected area, extract the data of the skin, bone and soft tissue parts of the affected area from the finger to the elbow joint, and reconstruct them into three-dimensional models for subsequent generation of the original design of the brace; 2) S2, Original design of the brace: The affected skin portion obtained in step S1 is processed to generate a complete original design scheme for the brace without cutouts or segments, which will be used for subsequent optimization of the brace structure. 3) S3, Support Structure Optimization: The stress and heat distribution of the brace were simulated when the patient wore it. Computer simulation was performed, and based on the static and thermodynamic results obtained from finite element analysis, lattice cutouts were generated on the complete brace. 4) S4, Detailed design of the support: The lattice cutout obtained in step S3 is divided into double helix slices, and edging is added to the edges of the two slices of the cutout support. Then, design details including semi-circular guide grooves, C-shaped guide grooves and accessory bases are added to make the lattice cutout a cutout support design scheme. 5) S5, Bracing fabrication and inspection: The hollowed-out brace design scheme with refined design in step S4 was prototyped and produced, and then tested after assembly. The optimization of the S3 support structure includes the following sub-steps: S31. Finite element preprocessing: Import the three-dimensional reconstructed skin, bone and soft tissue models of the affected area into the finite element analysis software, perform mesh generation and assign various physical properties to the human tissues to which they belong; in the finite element analysis software, constrain the relationship between the patient's hand model and the complete model of the brace, including contact and friction, and then add loads to simulate one or more common hand movements. S32. Finite Element Analysis: Output and save the stress distribution on the surface of the complete brace under one or more common hand movements; simulate the heat distribution of the hand model and the complete brace model when the patient wears the brace, and output and save the temperature distribution on the surface of the complete brace. S33. Generating lattice cutouts: The finite element results are converted into discrete points on the surface of the complete support, then into Thiessen polygons, and finally into lattice cutouts of the support. The biomechanical analysis-based personalized wrist brace design method improves the fit between the brace and the affected area and the comfort of wearing it, while ensuring sufficient mechanical strength to guarantee therapeutic efficacy. A complete brace is generated based on a 3D model of the affected area reconstructed from the patient's CT scan to ensure fit and eliminate pressure and friction points. Then, the patient's local musculoskeletal system is simulated by computer, and lattice perforations are generated on the complete brace based on the static and thermodynamic results obtained from finite element analysis. The shape of the perforations is generated by computer algorithms based on the static and thermal fields of the affected area surface. Areas with high stress concentration have denser lattice perforations with smaller areas to increase strength and eliminate stress concentration points, while areas with lower stress and higher temperature have sparser lattice perforations with larger areas to reduce heat accumulation and structural weight. The method also minimizes the negative impact of seams on the brace's unidirectional stiffness without affecting patient comfort.

2. The design method for a personalized wrist brace based on biomechanical analysis according to claim 1, characterized in that: The S1 patient data collection includes the following sub-steps: S11. Reading Data: Use open-source or commercial software to read the patient's CT data; S12. Create Region of Interest: Create a region of interest (VOI) for the fracture site and hide the rest. S13, Adjusting the threshold: A skin mask is created in the VOI by adjusting the threshold; S14. Modify the selection: Use tools including the brush and eraser to finely modify the mask and ensure that all skin is correctly selected; S15. Reconstruction Calculation: Perform three-dimensional reconstruction calculation; S16. Correct the rebuild error; S17. Export the reconstruction results.

3. The design method for a personalized wrist brace based on biomechanical analysis according to claim 1, characterized in that: The original design of the S2 brace includes the following sub-steps: S21. Establish a suitable selection area: Establish a suitable selection area for the affected skin area; S22, Offset: Perform an offset operation on the appropriate selection area; S23, Smoothing and Shaping: Use the smoothing command to remove anatomical features, including blood vessels on the back of the hand and palm lines, from the offset selection area. Subsequently, suitable selection areas are established on the three-dimensional shape of the ulnar styloid process and the radial styloid process, offset outward by 1 mm to 5 mm, in order to prevent the formation of pressure points; S24. Shelling: Shell the smoothed selected area outward by 1 mm to 10 mm to form a complete wrist brace. The thickness of this shelling is the thickness of the brace in the final product. S25. Repair Model: Inspect and repair the original design of the support after shelling to ensure that the three-dimensional model is free from errors, including incorrect normal direction, broken surfaces, discrete surfaces, holes, and overlapping surfaces.

4. The design method for a personalized wrist brace based on biomechanical analysis according to claim 3, characterized in that: The appropriate selection area in the S21 sub-step has its distal boundary at the middle section of the second phalanx, and should retain at least one-third of the length of the second phalanx; the remaining four fingers are cut to the middle section of the second to fifth metacarpal bodies, and should retain at least half the length of the metacarpal body, and should not exceed the bottom edge of the metacarpal head at most. The proximal boundary of the selected area is the middle segment of the radius and ulna shafts, and should be no less than one-third of the length of the radius and ulna, and no longer than the bottom edge of the radial head.

5. The design method for a personalized wrist brace based on biomechanical analysis according to claim 1, characterized in that: In the S31 sub-step, one or more common hand movements include at least wrist extension, flexion, and rotation; In the S33 sub-step, the volume of the lattice cutout should not exceed 90% of the volume of the complete support, and at the same time, the volume of the lattice cutout should not be less than 50% of the volume of the complete support.

6. The design method for a personalized wrist brace based on biomechanical analysis according to claim 1, characterized in that: The detailed design of the S4 support includes the following sub-steps: S41, Double Helix Segmentation: Using a 360° twisted plane, the lattice is hollowed out and divided into two double helix segments. The thickness of the plane is 1 mm to 5 mm, and the thickness of the plane is the distance between the two segments after division. S42. Edge binding: Bind the edges of the two hollow support pieces, with a binding width of 1~20mm. S43. Add semi-circular guide grooves: Add at least two semi-circular guide grooves to the joint of the two spiral segments to guide the two support segments to move in a preset direction during support installation or fine adjustment. S44. Add C-shaped guide grooves: Add C-shaped guide grooves in pairs on both sides of the joint of the two spiral segments to restrict the movement of the steel cable and ensure that the steel cable will not slip when the locking mechanism pulls it. S45. Add accessory base: The accessory base is used to install one or more locking mechanisms; a steel cable starts from the locking mechanism, crosses back and forth through the C-shaped guide grooves on both sides of one or two joints, and finally returns to the same locking mechanism; the steel cable and the locking mechanism together form a fixing mechanism to fix the support; the tension of the steel cable can be adjusted by turning the knob to achieve fine adjustment of the support tightness, which can reliably lock the length of the steel cable to fix the support, and the support can also be released and removed by loosening the steel cable.

7. The design method for a personalized wrist brace based on biomechanical analysis according to claim 1, characterized in that: The S5 brace fabrication and inspection includes the following sub-steps: S51. Additive manufacturing: The hollowed-out wrist brace is made using additive manufacturing. S52. Post-processing: The hollowed-out wrist brace is subjected to post-processing operations including removing residual powder, polishing, cleaning, removing residual liquid, secondary curing, and removing the support structure. S53. Assembly: Use adhesive or riveting to fix the locking mechanism to the main body of the support. Pass the steel cable through the C-shaped guide groove in sequence and connect it to the locking mechanism to complete the assembly. S54. Trial Wear Test: The device is delivered to the patient for trial wear, and patient feedback is collected through methods such as verbal description, questionnaires, and interviews, which will serve as a reference for future improvements.

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