Proximal humerus fracture restoration and preparation method thereof

Abstract

The invention relates to the technical field of medical instruments, and discloses a proximal humerus fracture restoration preparation method which comprises the following steps: acquiring proximal humerus CT image data of a patient, and constructing a three-dimensional digital skeleton model through medical image processing software; on the basis of the three-dimensional digital skeleton model, personalized adaptation parameters of the prosthesis are determined by adopting a parameterized design algorithm, and the personalized adaptation parameters comprise anatomical angle parameters, medullary cavity curvature parameters and dimension specification parameters; according to the personalized adaptation parameters, a digital model of the modular restoration is generated through computer aided design software, and the digital model comprises a first bearing part and a second bearing part which are connected through a splicing structure and an adjusting connection part arranged between the first bearing part and the second bearing part. The purpose of the invention is to realize personalized precise adaptation, have intraoperative regulation ability, and integrate advanced manufacturing and biological activity technologies.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a method for preparing a proximal humeral fracture repair and the repair thereof. Background Technology

[0002] Proximal humeral fractures are among the most common osteoporotic fractures in clinical practice, especially in elderly patients. Currently, internal fixation treatments for complex proximal humeral fractures (such as Neer's three-part and four-part fractures) mainly include locking proximal humeral plates (LPHP), intramedullary nail systems, and humeral head replacement. Locking plate systems provide angular stability through multi-angle locking screws, and their design has become standardized and serialized, aiming to provide stable mechanical support for the fracture fragments. Intramedullary nail systems adopt a central fixation concept, aiming to reduce soft tissue stripping. For severe comminuted fractures, humeral head replacement surgery is often used to replace the damaged humeral head. In terms of manufacturing, existing implants are usually produced on a standardized scale, that is, a series of products with several specifications and models are designed based on the average anatomical data of the population, and manufactured through traditional forging, casting, and machining (such as CNC) processes.

[0003] However, the aforementioned existing technologies still have significant drawbacks. First, standardized designs cannot accurately match each patient's unique anatomical parameters (such as neck-shaft angle, posterior tilt angle, and medullary cavity morphology), resulting in poor fit between the implant and the bone surface, easily causing stress concentration, and leading to complications such as screw cutting and internal fixation failure. Second, the integrated rigid structure lacks the ability to make intraoperative fine adjustments, and cannot cope with the precise adaptation required due to the complexity and variety of fracture types during surgery. It often requires the surgeon to perform multiple trial moldings and adjustments, prolonging the operation time. Third, traditional subtractive manufacturing processes have limitations in producing complex anatomical structures, making it difficult to efficiently and economically manufacture implants with personalized curved surfaces and internal structures. Finally, existing technologies lack comprehensive consideration of osseointegration efficiency and postoperative infection prevention. Summary of the Invention

[0004] The purpose of this invention is to propose a method for preparing a proximal humeral fracture repair and the repair itself, which can achieve personalized and precise fitting, have intraoperative adjustment capabilities, and integrate advanced manufacturing and bioactive technologies.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A method for preparing a proximal humeral fracture repair, comprising the following steps: S1. Obtain CT image data of the proximal humerus of the patient and construct a three-dimensional digital bone model using medical image processing software; S2. Based on the three-dimensional digital bone model, a parametric design algorithm is used to determine the personalized adaptation parameters of the prosthesis. The personalized adaptation parameters include anatomical angle parameters, medullary cavity curvature parameters, and size specifications. S3. Based on the personalized adaptation parameters, a digital model of the modular prosthesis is generated using computer-aided design software. The digital model includes a first load-bearing component and a second load-bearing component connected by a splicing structure, as well as an adjustment connecting component disposed between the two components. S4. Based on the digital model, the solid structures of the first load-bearing component, the second load-bearing component, and the adjusting connection component are prepared layer by layer using additive manufacturing technology; S5. Perform surface treatment and quality inspection on each component after preparation to ensure that it meets the standards for medical device implantation.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Furthermore, the acquisition of CT image data of the proximal humerus of the patient is carried out using thin-slice scanning technology to obtain CT image data with a slice thickness of no more than 0.625 mm, and the data is stored and transmitted in DICOM format; The medical image processing software is Mimics and 3D Slicer. The processing includes image segmentation, three-dimensional reconstruction and model optimization. The generated three-dimensional digital skeletal model contains the complete anatomical structure of the proximal humerus, including the humeral head, anatomical neck, surgical neck, greater and lesser tubercles and the humeral metaphysis. The model optimization includes removing excess bone spurs, defects, and surface roughness caused by scanning and imaging issues.

[0008] Furthermore, the anatomical angle parameters include the back tilt angle α and the neck-shaft angle β, wherein the back tilt angle α ranges from 20° to 40° and the neck-shaft angle β ranges from 110° to 140°. The medullary canal curvature parameters are obtained by calculating the radius of curvature and curvature of the inner wall of the medullary canal, including the diameter of the proximal medullary canal opening, the diameter of the isthmus of the medullary canal, and the curvature angle of the medullary canal; The dimensional specifications include the total length of the restoration, the cross-sectional dimensions of each component, and the dimensions of the connection structure. The parametric design algorithm employs automatic identification and measurement technology based on anatomical landmarks to ensure the accuracy and repeatability of parameter determination.

[0009] Furthermore, the splicing structure is a sliding groove connection mechanism, including a guide groove disposed on the first connection interface of the first bearing component and a mating slider disposed on the second connection interface of the second bearing component; the adjusting connection component is a wedge-shaped adjusting block, the wedge angle of which is determined according to the anatomical angle parameter in the personalized adaptation parameters; The digital model generation process also includes designing anti-slip structures and suture fixation structures on the surface of the restoration. The anti-slip structure is a uniformly distributed array of protrusions, and the suture fixation structure is an anatomical hole design specifically for fixing nodules of different sizes.

[0010] Furthermore, the step of preparing the material layer by layer using additive manufacturing technology specifically includes: Powder spreading process: A metal powder layer is spread on the molded substrate using a powder spreading device, and the thickness of a single powder layer is controlled to be between 20 micrometers and 50 micrometers. Cladding process: Based on the material properties of the metal powder, optimize the power parameters, scanning speed and scanning strategy of the laser to selectively melt specific areas of the powder layer, so that it is metallurgically bonded to the already formed part; Environmental control process: Throughout the entire preparation process, the atmosphere inside the molding chamber is controlled to be a high-purity inert gas atmosphere, with the oxygen content maintained below 1000 ppm, to prevent the metal powder from undergoing an oxidation reaction at high temperatures.

[0011] Furthermore, the surface treatment includes sandblasting, chemical polishing, and electrolytic polishing, so that the surface roughness Ra value is controlled within the range of 1.6-3.2 μm; Quality inspection includes dimensional accuracy inspection, mechanical property inspection, and biocompatibility inspection; The dimensional accuracy inspection is performed using a coordinate measuring machine for full-dimensional inspection. The mechanical property inspection includes static compression testing and fatigue testing. The biocompatibility inspection is performed according to ISO 10993 standard for cytotoxicity and sensitization testing.

[0012] A modular proximal humeral fracture repair device, comprising: The first load-bearing component has a load-bearing contact surface and a first connection interface adapted to the humeral head bone bed; The second load-bearing component has a support contact surface that conforms to the humeral medullary cavity and a second connection interface; The first connection interface and the second connection interface are connected and their relative positions can be adjusted through a splicing structure; An adjustable connecting component is positioned between the first and second supporting components to achieve precise fine-tuning of the relative positions of the two components.

[0013] Furthermore, the bearing contact surface of the first bearing component is a curved surface structure adapted to the anatomical shape of the humeral head bone bed, and the radius of curvature is individually designed according to the specific anatomical characteristics of the patient; the first connection interface is a groove structure with specific guiding characteristics, the cross-sectional shape of the groove is T-shaped, dovetail-shaped or wedge-shaped, the groove depth is 5-15mm and the width is 3-8mm.

[0014] Furthermore, the supporting contact surface of the second bearing component is a curved structure that conforms to the shape of the inner wall of the humeral medullary cavity, and the second connecting interface is a slider structure that cooperates with the first connecting interface. The cooperation gap between the slider and the groove is controlled within the range of 0.1-0.3mm.

[0015] Furthermore, the adjusting connecting component is a wedge-shaped adjusting block, made of medical-grade titanium alloy or polyetheretherketone material, with a wedge angle of 5° to 15°, a length of 10 to 30 mm, and a width that matches the splicing structure. The first and second supporting components are also provided with multiple sets of suture fixing holes, with a diameter of 1.0-2.0 mm, and the positions correspond to the anatomical attachment points of the large and small nodules.

[0016] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: This invention constructs a three-dimensional bone model by acquiring the patient's CT images. Using parametric design, it determines personalized adaptation parameters such as anatomical angles and medullary canal curvature, accurately matching the patient's unique anatomical parameters. This solves the problem of poor bone surface fit in standardized designs, avoiding complications such as screw cutting and internal fixation failure caused by stress concentration. The modular prosthesis design, incorporating adjustable connecting components, overcomes the limitations of rigid, one-piece structures, enabling flexible micro-adjustments during surgery without the need for multiple trial moldings, effectively shortening surgical time. Utilizing additive manufacturing technology overcomes the limitations of traditional subtractive manufacturing in producing complex anatomical structures, enabling efficient and economical fabrication of implants with personalized curved surfaces and internal structures. Surface treatment improves osseointegration efficiency, and quality testing ensures compliance with medical device implantation standards, indirectly reducing the risk of postoperative infection. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the overall process for preparing a proximal humeral fracture repair body according to the present invention. Figure 2 This is a schematic diagram of the modular repair structure of the present invention; Figure 3 This is a schematic diagram of the overall connection structure of the repair body of the present invention; Figure 4 This is a schematic diagram of the explosive connection structure of the repair body of the present invention; Figure 5 This is a schematic diagram of the explosive connection structure of the repair body from another perspective of the present invention; Figure 6 This is a schematic diagram of the overall connection structure after the present invention is assembled.

[0018] In the figure: 1. First load-bearing component; 11. Load-bearing contact surface; 12. First connection interface; 2. Second load-bearing component; 21. Support contact surface; 22. Second connection interface; 3. Adjustable connection component. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] like Figures 1-2 As shown, a method for preparing a proximal humeral fracture repair according to the present invention includes the following steps: S1. Obtain CT image data of the proximal humerus of the patient and construct a three-dimensional digital bone model using medical image processing software; S2. Based on a three-dimensional digital bone model, a parametric design algorithm is used to determine the personalized adaptation parameters of the prosthesis. The personalized adaptation parameters include anatomical angle parameters, medullary cavity curvature parameters, and size specifications. S3. Based on the personalized adaptation parameters, a digital model of the modular prosthesis is generated using computer-aided design software. The digital model includes a first load-bearing component and a second load-bearing component connected by a splicing structure, as well as an adjustment connection component set between the two components. S4. Based on the digital model, the solid structures of the first load-bearing component, the second load-bearing component, and the adjusting connection component are prepared layer by layer using additive manufacturing technology; S5. Perform surface treatment and quality inspection on each component after preparation to ensure that it meets the standards for medical device implantation.

[0021] Based on the above preparation method, the specific implementation steps are as follows. It should also be noted that the following preparation method is merely an exemplary implementation method used to illustrate the principle of this disclosure, but this disclosure is not limited thereto.

[0022] A thin-slice scan of the proximal humerus on the affected side was performed using a Siemens SOMATOM ForceCT scanner to obtain high-resolution two-dimensional tomographic images. The scanned data was exported and stored in DICOM standard format. Subsequently, the DICOM data was imported into Materialise's Mimics Innovation Suite 26.0 medical image processing software. In this software, a threshold segmentation algorithm was first used to initially distinguish bone tissue from surrounding soft tissue. Then, the target humerus was separated using a region growing tool. Finally, manual erasure and editing tools were used to finely remove irrelevant bone fragments and artifacts, generating a three-dimensional mesh model containing only the proximal humerus. This model fully includes all key anatomical structures such as the humeral head, anatomical neck, surgical neck, greater tuberosity, lesser tuberosity, and part of the humeral shaft. The aforementioned 3D mesh model was imported into 3-Matic 16.0 software, and its built-in parametric design module was used to determine personalized adaptation parameters. The specific process was as follows: First, the software automatically identified and labeled key anatomical landmarks, including the center point of the humeral head, the central axis of the humeral shaft, the highest point of the greater tubercle, and the highest point of the lesser tubercle. Then, based on these landmarks, the algorithm automatically calculated and output anatomical angle parameters: posterior tilt angle α and neck-shaft angle β. The medullary canal curvature parameters were obtained by calculating the best-fit ellipse of multiple cross-sections of the medullary canal wall, including the diameter of the proximal medullary canal opening, the diameter of the isthmus of the medullary canal, and the medullary canal curvature angle. Finally, based on the above parameters and combined with clinical needs, the algorithm automatically derived the size specifications of the prosthesis, including the total length, the cross-sectional dimensions of each component, and the specific dimensions of the connecting structures. All the personalized parameters obtained were input into the Siemens NX 1980 series computer-aided design software. First, based on the dimensional specifications, preliminary solid models of the first and second load-bearing components were created. The radius of curvature of the load-bearing contact surface of the first load-bearing component was personalized according to the curvature of the humeral head bed of the patient. The profile of the support contact surface of the second load-bearing component was designed to fit closely to the curved surface of the patient's medullary cavity. Then, the splicing structure was constructed. Finally, the adjustment connection component, namely the wedge-shaped adjustment block, was designed. Its wedge angle was based on the adjustment requirements of the back tilt angle α and neck-shaft angle β obtained above. Finally, all components were virtually assembled in the software assembly module, interference was checked, and the model was exported as a digital model in STL format for subsequent manufacturing. Using the EOS M 290 metal additive manufacturing equipment, solid parts are prepared layer by layer through selective laser melting (SLM). First, medical-grade Ti-6Al-4V ELI titanium alloy powder is filled into the powder supply chamber of the equipment. The powder particle size is controlled between 15-53μm after sieving. The obtained STL model is then imported into the equipment's operating software EOSPRINT 2.6. The software automatically slices the model, and the layer thickness parameter is set to 40μm. At the same time, the support structure optimization algorithm in the software automatically generates the necessary support structure in areas with a hanging angle greater than 45° based on the geometric characteristics of the model to ensure printing success rate and accuracy. The laser scanning path adopts an island scanning strategy to disperse internal stress. The laser power is optimized to 280W based on the material characteristics of titanium alloy, the scanning speed is set to 1200mm / s, and the scanning interval is 0.1mm. The entire printing process is carried out in a forming chamber continuously supplied with high-purity argon gas. The oxygen content in the chamber is monitored in real time by a sensor and always maintained below 500ppm to prevent oxidation of the metal powder. The first support component, the second support component, and the wedge-shaped adjustment block are printed sequentially. After printing, the parts are removed from the substrate using wire cutting, and the supporting structure is removed by fitter and CNC machining. Surface treatment follows: first, sandblasting with 120-mesh white corundum abrasive removes surface powder; then, chemical polishing initially reduces surface roughness; finally, electrolytic polishing controls the surface roughness Ra value of the main surface in contact with bone to within 2.0 μm. Quality inspection includes: full-dimensional inspection of key dimensions of the parts using a ZEISS CONTURA coordinate measuring machine to ensure deviations from the digital model are within ±0.1 mm; static compression and fatigue tests using an INSTRON 5966 universal testing machine, with results meeting ISO 5832-3 standards; and cytotoxicity and sensitization tests conducted by a qualified testing institution according to ISO 10993-5 and -10 standards, with results showing no potential toxicity or sensitization. After all tests are passed, the parts are cleaned, packaged, and sterilized, ultimately yielding a modular proximal humeral fracture repair body that meets medical device implantation standards. Figure 6 The image shows the assembled prosthesis, which is placed on the lateral side of the humeral shaft. It should also be noted that different sizes can be made to accommodate different populations. The bone sizes of men and women, adults and children vary greatly, and adjustment blocks alone cannot cover the differences in age, gender, and bone size among different populations. Therefore, the entire prosthesis can be customized.

[0023] Thin-slice scanning technology was used to acquire CT image data of the proximal humerus of patients, with a slice thickness of no more than 0.625 mm. The data was stored and transmitted in DICOM format. The medical image processing software is Mimics, 3D Slicer, or other medical image processing platforms. The processing includes image segmentation, 3D reconstruction, and model optimization. The generated 3D digital skeletal model contains the complete proximal anatomical structure of the humerus, including the humeral head, anatomical neck, surgical neck, greater and lesser tubercles, and humeral metaphysis. Model optimization includes removing excess bone spurs, defects, and surface roughness caused by scanning imaging issues. In the specific implementation of the step of acquiring CT image data of the proximal humerus of the patient, the aforementioned Siemens SOMATOM Force dual-source CT scanner was used, with a minimum slice thickness of 0.5mm. In this example, it was set to 0.625mm, which was sufficient to clearly distinguish the trabecular bone structure. After the scan was completed, the original two-dimensional tomographic sequence images were burned to a CD in DICOM format for archiving and transmission. In the three-dimensional reconstruction process, Mimics software was used. First, the threshold was set to a lower limit of 226HU and an upper limit of 3071HU based on the CT value. The software automatically selected all bone tissue within this range. Then, the target humerus was precisely outlined by manually drawing the region of interest. Pixels of connected bones such as the glenoid fossa and clavicle were erased using tools. Finally, a high-quality triangulation algorithm was used to generate a three-dimensional model, and the model was smoothed and optimized to reduce holes. The final STL format three-dimensional digital bone model file clearly and completely includes the humeral head, anatomical neck, surgical neck, greater tuberosity, lesser tuberosity, and humeral metaphysis.

[0024] The anatomical angle parameters include the back tilt angle α and the neck-shaft angle β, where the back tilt angle α ranges from 20° to 40° and the neck-shaft angle β ranges from 110° to 140°. The curvature parameters of the medullary canal are obtained by calculating the radius of curvature and the degree of curvature of the inner wall of the medullary canal, including the diameter of the proximal medullary canal opening, the diameter of the isthmus of the medullary canal, and the curvature angle of the medullary canal; Dimensional specifications include the total length of the restoration, the cross-sectional dimensions of each component, and the dimensions of the connecting structures; The parametric design algorithm employs automatic identification and measurement technology based on anatomical landmarks to ensure the accuracy and repeatability of parameter determination. In the specific implementation of determining personalized adaptation parameters using the parametric design algorithm, the 3-Matic software is used. The software's built-in algorithm automatically identifies the following anatomical landmarks: the uppermost, lowermost, anteriormost, and posteriormost points of the humeral head; the most prominent point of the greater tubercle; the deepest point of the intertubercular groove; and multiple points on the midline of the humeral shaft. Based on these points, the algorithm automatically constructs the best-fit sphere for the humeral head, the best-fit cylinder for the humeral shaft, and related reference planes and axes. The method for measuring the posterior tilt angle α is as follows: on the transverse section, find the center point of the humeral head and the center point of the metaphysis and draw a line connecting them. Then, draw a line perpendicular to the line connecting the medial and lateral condyles of the distal humerus. The angle between these two lines is the posterior tilt angle α. The software automatically calculates and outputs this value. The angle value, the neck-shaft angle β, is measured as follows: on the coronal plane, the angle between the line connecting the center of the humeral head and the center of the metaphysis and the axis of the humeral shaft. The software outputs the angle value. The medullary canal curvature parameter is obtained as follows: the software makes a cross-section every 5 mm along the longitudinal axis of the medullary canal. On each cross-section, the software calculates the best-fit ellipse of the medullary canal wall profile, thus obtaining the major and minor axis diameters of that cross-section. The diameter of the proximal medullary canal opening is taken as the major axis diameter of the ellipse of the uppermost cross-section, and the diameter of the isthmus of the medullary canal is taken as the minimum value of the major axis diameter of the ellipse among all cross-sections. The medullary canal curvature angle is obtained by calculating the maximum angle of the medullary canal centerline deviating from the axis of the humeral shaft. All dimensional specifications, such as the total length of the prosthesis being 65 mm, are automatically calculated and generated by the software based on the above measurement results and the built-in clinical rule base, ensuring the objectivity, accuracy, and repeatability of the parameter determination.

[0025] like Figure 4 , Figure 5 As shown; the splicing structure is a sliding groove connection mechanism, including a guide groove set on the first connection interface of the first bearing component and a matching slider set on the second connection interface of the second bearing component; the adjusting connection component is a wedge-shaped adjusting block, and its wedge angle is determined according to the anatomical angle parameter in the personalized adaptation parameters; The digital model generation process also includes designing anti-slip structures and suture fixation structures on the surface of the prosthesis. The anti-slip structure is a uniformly distributed array of protrusions, and the suture fixation structure is an anatomical hole design specifically for fixing the large and small tubercles. The creation of the suture fixation structure involves creating a through hole at the projection position of the highest point of the large and small tubercles determined by the preoperative CT image. The axis of the hole is designed to be perpendicular to the bone surface to facilitate suturing.

[0026] The specific steps involved in layer-by-layer fabrication using additive manufacturing technology include: Powder spreading process: A metal powder layer is spread on the molded substrate using a powder spreading device, and the thickness of a single powder layer is controlled to be between 20 micrometers and 50 micrometers. Cladding process: Based on the material properties of the metal powder, optimize the power parameters, scanning speed and scanning strategy of the laser to selectively melt specific areas of the powder layer, so that it is metallurgically bonded to the already formed part; Environmental control process: Throughout the preparation process, the atmosphere inside the molding chamber is controlled as a high-purity inert gas atmosphere, with the oxygen content maintained below 1000 ppm to prevent oxidation of the metal powder at high temperatures; the preferred range for the deposition thickness is 30 to 40 micrometers; the metal powder is medical-grade titanium alloy powder with a normally distributed particle size distribution, where the D10 value is not less than 15 micrometers and the D90 value is not greater than 60 micrometers, to ensure good powder flowability and cladding formability. In the cladding process: The laser power parameters are dynamically optimized and adjusted according to the type of metal powder, deposition thickness, and thermophysical properties; for titanium alloy materials, the laser power setting range is 200 watts to 400 watts; the scanning strategy employs one or a combination of partitioned scanning, island scanning, or rotating scanning strategies to reduce internal stress and thermal deformation. In the environmental control process: the inert gas is high-purity argon, with a purity of not less than 99.999%; real-time monitoring of oxygen content is carried out through an integrated oxygen analyzer, forming a closed-loop control system. When the oxygen content exceeds the preset threshold, the system automatically triggers an alarm and replenishes inert gas to prevent oxidation.

[0027] Surface treatment includes sandblasting, chemical polishing, and electrolytic polishing, so that the surface roughness Ra value is controlled within the range of 1.6-3.2μm; Quality inspection includes dimensional accuracy inspection, mechanical property inspection, and biocompatibility inspection; Dimensional accuracy was inspected using a coordinate measuring machine (CMM) for full-dimensional inspection. Mechanical property testing included static compression and fatigue testing. Biocompatibility testing was conducted according to ISO 10993 standards for cytotoxicity and sensitization. Sandblasting used 120-mesh white alumina abrasive at a nozzle pressure of 0.4 MPa, with the nozzle approximately 15 cm from the workpiece. The abrasive was sprayed evenly onto the workpiece surface until all surface powder was removed. Chemical polishing used a mixed acid solution with a concentration of 3% hydrofluoric acid, 7% nitric acid, and the remainder being deionized water. The workpiece was completely immersed in the acid solution and magnetically stirred for 2 minutes before being immediately removed and rinsed with plenty of pure water. Electrolytic polishing used an electrolyte solution with a concentration of 10% perchloric acid and 90% acetic acid. The workpiece was used as the anode, and a stainless steel plate as the cathode, with an electrode spacing of 3 cm. The reaction was carried out in a constant temperature bath at 15°C with a 30V DC voltage applied for 30 seconds. After treatment, the Ra value was measured to be 2.0 μm using a Taylor Hobson surface roughness meter. In quality inspection, dimensional accuracy was measured using a ZEISS abrasive. The CONTURA coordinate measuring machine, equipped with a VAST XXT probe, was used to inspect all critical dimensions and geometric tolerances of the restoration in a constant temperature chamber of 20°C ± 1°C, according to GD&T standards. The deviations between the measured dimensions and the CAD model were all within ± 0.08 mm. In the mechanical property test, the static compression test was performed until the material yielded, and the yield strength was measured to be 795 MPa and the compressive strength to be 905 MPa. The fatigue test showed no fracture after 5 million cycles under a 500 N load. The biocompatibility test report, issued by a third-party testing institution, showed a relative cell proliferation rate (RGR) of 98% (>75% is considered acceptable). No skin allergic reactions were observed in the guinea pig maximization test.

[0028] A modular proximal humeral fracture repair device, comprising: The first load-bearing component 1 has a load-bearing contact surface 11 adapted to the humeral head bone bed and a first connection interface 12; The second load-bearing component 2 has a support contact surface 21 that conforms to the humeral medullary cavity and a second connection interface 22; The first connection interface 12 and the second connection interface 22 are connected and their relative positions can be adjusted through a splicing structure; Adjustable connecting component 3 is positioned between the first bearing component 1 and the second bearing component 2 to achieve precise fine-tuning of the relative positions of the two components; The splicing structure provides initial positioning and anti-displacement functions, while the adjustable connecting components provide personalized adaptation functions after surgery.

[0029] like Figure 4 , Figure 5As shown; the bearing contact surface 11 of the first bearing component 1 is a curved surface structure adapted to the anatomical shape of the humeral head bone bed, and the radius of curvature is individually designed according to the specific anatomical characteristics of the patient; the first connecting interface 12 is a groove structure with specific guiding characteristics, the cross-sectional shape of the groove is T-shaped, dovetail-shaped or wedge-shaped, the groove depth is 5-15mm and the width is 3-8mm, providing stable guiding function and anti-rotation function; the supporting contact surface 21 is a curved surface that conforms to the shape of the inner wall of the patient's humeral medullary cavity, and the design of this curved surface is also based on the patient's CT three-dimensional model, and its cross-sectional shape simulates the natural shape of the medullary cavity, which is approximately elliptical; the second connecting interface 22 is a slider structure that cooperates with the first connecting interface 12, ensuring that the slider 32 can slide smoothly in the groove 31 during the adjustment process, and can provide sufficient connection stability after final locking to prevent micro-movement.

[0030] like Figure 4 , Figure 5 As shown; the supporting contact surface 21 of the second bearing component 2 is a curved structure that conforms to the shape of the inner wall of the humeral medullary cavity, and the second connecting interface 22 is a slider structure that cooperates with the first connecting interface 12. The cooperation gap between the slider and the groove is controlled within the range of 0.1-0.3mm to ensure connection stability while allowing necessary adjustment and movement. To facilitate intraoperative operation, anti-slip textures are etched on the top and two sides of the wedge-shaped adjustment block 4 using a laser marking machine. The texture is a cross-shaped mesh with a depth of 0.1mm. On one side, depth scale markings are processed using micro-engraving technology. The markings contain a series of precise lines and numbers. Each 1mm insertion depth corresponds to a short line, and each 5mm insertion depth corresponds to a long line and number markings such as 5, 10, 15. The surgeon can intuitively understand the insertion depth by observing the scale, thereby achieving precise and quantitative adjustment of the prosthesis size.

[0031] like Figure 3 , Figure 6 As shown; the adjusting connecting component is a wedge-shaped adjusting block, made of medical-grade titanium alloy or polyetheretherketone material, with a wedge angle of 5° to 15°, a length of 10 to 30 mm, and a width that matches the splicing structure; The first and second support components 1 and 2 are also provided with multiple sets of suture fixation holes, with a diameter of 1.0-2.0 mm. The holes are positioned corresponding to the anatomical attachment points of the greater and lesser tubercles. Multiple sets of suture fixation holes are provided on the prosthesis. Their positions are not arbitrary but determined by projection based on the anatomical attachment points such as the highest point of the greater tubercle, the highest point of the lesser tubercle, and the intertubercular groove identified on the preoperative 3D model. For example, two holes are specifically designed on the anterolateral aspect of the prosthesis, corresponding to the posterior edge of the biceps brachii long head tendon groove, while the other three holes are designed on the greater tubercle crest to facilitate intraoperative suturing and fixation of the torn rotator cuff tendon, achieving anatomical reconstruction.

[0032] The prosthesis also includes surface functional structures: a uniformly distributed array of anti-slip protrusions on the load-bearing contact surface to ensure uniform pressure distribution; a bioactive coating: a hydroxyapatite bioactive coating is applied to the load-bearing and support contact surfaces to promote bone ingrowth and bio-fixation; the coating is prepared using plasma spraying or electrochemical deposition techniques to ensure the bonding strength and bioactivity between the coating and the substrate; and an antibacterial functional layer: a silver-containing antibacterial coating or an antibiotic-loaded coating is applied to the surface of the prosthesis, prepared using micro-arc oxidation or sol-gel techniques to continuously release antibacterial factors to prevent postoperative infection; the antibacterial coating and the bioactive coating are designed in layers to ensure antibacterial effect without affecting the bone integration process.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a proximal humeral fracture repair, characterized in that, Includes the following steps: S1. Obtain CT image data of the proximal humerus of the patient and construct a three-dimensional digital bone model using medical image processing software; S2. Based on the three-dimensional digital bone model, a parametric design algorithm is used to determine the personalized adaptation parameters of the prosthesis. The personalized adaptation parameters include anatomical angle parameters, medullary cavity curvature parameters, and size specifications. S3. Based on the personalized adaptation parameters, a digital model of the modular prosthesis is generated using computer-aided design software. The digital model includes a first load-bearing component and a second load-bearing component connected by a splicing structure, as well as an adjustment connecting component disposed between the two components. S4. Based on the digital model, the solid structures of the first load-bearing component, the second load-bearing component, and the adjusting connection component are prepared layer by layer using additive manufacturing technology; S5. Perform surface treatment and quality inspection on each component after preparation to ensure that it meets the standards for medical device implantation.

2. The method for preparing a proximal humeral fracture repair according to claim 1, characterized in that, The acquisition of CT image data of the proximal humerus of the patient is carried out using thin-slice scanning technology to obtain CT image data with a slice thickness of no more than 0.625 mm, and the data is stored and transmitted in DICOM format; The medical image processing software is Mimics and 3D Slicer. The processing includes image segmentation, three-dimensional reconstruction and model optimization. The generated three-dimensional digital skeletal model contains the complete anatomical structure of the proximal humerus, including the humeral head, anatomical neck, surgical neck, greater and lesser tubercles and the humeral metaphysis. The model optimization includes removing excess bone spurs, defects, and surface roughness caused by scanning and imaging issues.

3. The method for preparing a proximal humeral fracture repair according to claim 1, characterized in that, The anatomical angle parameters include the back tilt angle α and the neck-shaft angle β, wherein the back tilt angle α ranges from 20° to 40° and the neck-shaft angle β ranges from 110° to 140°. The medullary canal curvature parameters are obtained by calculating the radius of curvature and curvature of the inner wall of the medullary canal, including the diameter of the proximal medullary canal opening, the diameter of the isthmus of the medullary canal, and the curvature angle of the medullary canal; The dimensional specifications include the total length of the restoration, the cross-sectional dimensions of each component, and the dimensions of the connection structure. The parametric design algorithm employs automatic identification and measurement technology based on anatomical landmarks to ensure the accuracy and repeatability of parameter determination.

4. The method for preparing a proximal humeral fracture repair according to claim 1, characterized in that, The splicing structure is a sliding groove connection mechanism, including a guide groove set on the first connection interface of the first bearing component and a matching slider set on the second connection interface of the second bearing component; the adjusting connection component is a wedge-shaped adjusting block, and its wedge angle is determined according to the anatomical angle parameter in the personalized adaptation parameters. The digital model generation process also includes designing anti-slip structures and suture fixation structures on the surface of the restoration. The anti-slip structure is a uniformly distributed array of protrusions, and the suture fixation structure is an anatomical hole design specifically for fixing nodules of different sizes.

5. The method for preparing a proximal humeral fracture repair according to claim 1, characterized in that, The specific steps of preparing the material layer by layer using additive manufacturing technology include: Powder spreading process: A metal powder layer is spread on the molded substrate using a powder spreading device, and the thickness of a single powder layer is controlled to be between 20 micrometers and 50 micrometers. Cladding process: Based on the material properties of the metal powder, optimize the power parameters, scanning speed and scanning strategy of the laser to selectively melt specific areas of the powder layer, so that it is metallurgically bonded to the already formed part; Environmental control process: Throughout the entire preparation process, the atmosphere inside the molding chamber is controlled to be a high-purity inert gas atmosphere, with the oxygen content maintained below 1000 ppm, to prevent the metal powder from undergoing an oxidation reaction at high temperatures.

6. The method for preparing a proximal humeral fracture repair according to claim 1, characterized in that, The surface treatment includes sandblasting, chemical polishing, and electrolytic polishing, so that the surface roughness Ra value is controlled within the range of 1.6-3.2 μm; Quality inspection includes dimensional accuracy inspection, mechanical property inspection, and biocompatibility inspection; The dimensional accuracy inspection is performed using a coordinate measuring machine for full-dimensional inspection. The mechanical property inspection includes static compression testing and fatigue testing. The biocompatibility inspection is performed according to ISO 10993 standard for cytotoxicity and sensitization testing.

7. A modular proximal humeral fracture repair body, prepared by the method described in claim 1, characterized in that, include: The first load-bearing component (1) has a load-bearing contact surface (11) adapted to the humeral head bone bed and a first connection interface (12). The second load-bearing component (2) has a support contact surface (21) that conforms to the humeral medullary cavity and a second connection interface (22). The first connection interface (12) and the second connection interface (22) are connected and their relative positions are adjusted through a splicing structure; Adjust the connecting component (3) between the first bearing component (1) and the second bearing component (2) to achieve precise fine-tuning of the relative position of the two components.

8. A proximal humeral fracture repair body according to claim 7, characterized in that, The bearing contact surface (11) of the first bearing component (1) is a curved surface structure adapted to the anatomical shape of the humeral head bone bed, and the radius of curvature is designed in a personalized manner according to the specific anatomical characteristics of the patient; the first connection interface (12) is a groove structure with specific guiding characteristics, the cross-sectional shape of the groove is T-shaped, dovetail-shaped or wedge-shaped, the groove depth is 5-15mm and the width is 3-8mm.

9. A proximal humeral fracture repair body according to claim 8, characterized in that, The supporting contact surface (21) of the second bearing component (2) is a curved structure that conforms to the shape of the inner wall of the humeral medullary cavity. The second connecting interface (22) is a slider structure that cooperates with the first connecting interface (12). The cooperation gap between the slider and the groove is controlled within the range of 0.1-0.3mm.

10. A proximal humeral fracture repair body according to claim 7, characterized in that, The adjusting connection component is a wedge-shaped adjusting block, made of medical-grade titanium alloy or polyetheretherketone material, with a wedge angle of 5° to 15°, a length of 10 to 30 mm, and a width that matches the splicing structure. The first support component (1) and the second support component (2) are also provided with multiple sets of suture fixing holes with a diameter of 1.0-2.0 mm, and the positions correspond to the anatomical attachment points of the large and small nodules.

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