A device for simulating the biomechanical state of bone tissue

Abstract

This invention relates to the field of biomaterial preparation technology, specifically disclosing a device for simulating the biomechanical state of bone tissue. The device includes a first wedge-shaped bidirectional moving device, a second wedge-shaped bidirectional moving device, a first optical axis, a second optical axis, a filament fixing seat, and a device base. The first and second optical axes are slidably connected to the moving ends of the filament clamps. The upper end of the device base is fixedly connected to the filament fixing seat and the optical axis base. There are two sets of optical axis bases, with a mold base fixedly connected between the two sets at the upper end of the device base. The mold base is fixedly connected to an open-hole plate. A double-track ball screw is fixedly connected to the inner side of the optical axis base. Clamp connectors are fixedly connected to the inner sides of the moving ends of the filament clamps. The first and second wedge-shaped bidirectional moving devices are movably connected between the clamp connectors. By adding directionally arranged filaments and applying tensile stress, the stress state of the organic components of bone tissue is simulated, thereby simulating the stress state of the inorganic components.

Description

Technical Field

[0001] This invention relates to the field of biomaterial preparation technology, specifically to a device for simulating the biomechanical state of bone tissue. Background Technology

[0002] Bones provide support, movement, and protection for the human body, but injuries and other factors can cause bone defects. Clinically, bone defect repair often involves implantation, leading to a growing demand for such materials. Currently, inorganic bone cement materials have become a research hotspot due to their excellent bioactivity, biocompatibility, and ability to transform into bone-like inorganic components (hydroxyapatite) within the body. However, their poor mechanical properties limit their practical application, making it crucial to improve these properties.

[0003] Bone is a composite material that combines elasticity and strength. Its mechanical properties are related to its composition and structure. Some studies use biomimetic methods to improve the mechanical properties of repair materials, such as biomimetic methods based on the composition and microstructure of bone tissue.

[0004] Chinese patent "A Fish Collagen-Based Bionic Bone Material and Its Preparation Method" (Application No.: CN202111623267.2, Publication No.: CN114262374A, Publication Date: 2022.04.01) discloses a fish collagen-based biomimetic bone material and its preparation method. The method involves mixing a fish collagen solution with a calcium chloride solution, centrifuging, freeze-drying, and shaping the mixture to obtain the fish collagen-based biomimetic bone material. The provided preparation method can complete the mineralization of fish collagen in vitro in a short time. The prepared fish collagen-based biomimetic bone material can effectively promote bone repair. However, this method only mimics the composition and fails to achieve matching with the microstructure and mechanical properties of bone tissue.

[0005] Chinese patent "A Method for Prestressed Reinforced Bone Cement Preparation" (Application No.: CN202211118425.3, Publication No.: CN115446976A, Publication Date: 2023.08.22) discloses a method for preparing prestressed reinforced bone cement. By pre-applying tensile stress to oriented fibers, compressive stress can be generated within the final component. This invention discloses a method for enhancing the mechanical properties of bone cement, but does not demonstrate its compatibility with the internal stress state of bone tissue.

[0006] In reality, the needle-like inorganic salt crystals and collagen fibers in human bone are primarily arranged longitudinally. Collagen fibers act as a reinforcing agent and generate internal pressure. Collagen fiber bundles bear tensile stress, while calcium phosphate salts bear compressive stress, forming an anisotropic structure and mechanical characteristics, thus achieving high mechanical properties. The method described above fails to consider the stress state of different components of bone tissue after arrangement, and the stress state of these different components is the most important factor in improving the mechanical properties of bone tissue. Summary of the Invention

[0007] In response to the problems raised in the background art, this invention proposes a bone tissue biomechanical state simulation device to simulate the stress state of different components of bone tissue, improve the mechanical properties of bone repair materials, and match them with the mechanical properties of different parts of bone tissue.

[0008] This invention discloses a bone tissue biomechanical state simulation device, comprising a first wedge-shaped bidirectional moving device, a second wedge-shaped bidirectional moving device, a first optical axis, a second optical axis, a filament fixing seat, and a device base plate. The upper end of the connecting plate is rotatably connected to the first and second optical axes, which are slidably connected to the moving end of a filament clamp. The upper end of the device base plate is fixedly connected to the filament fixing seat and an optical axis base. Two sets of optical axis bases are fixedly connected between the two sets at the upper end of the device base plate, with a mold base fixedly connected between them. An open-hole plate is fixedly connected to the mold base. A double-track ball screw is fixedly connected to the inner side of the optical axis base. Clamping connectors are fixedly connected to the inner side of the moving end of the filament clamp. The first and second wedge-shaped bidirectional moving devices are movably connected between the clamping connectors. The lower end of the connecting plate is fixedly connected to the moving end of a double-track ball screw linear module, and the fixed end of the double-track ball screw linear module is fixedly connected to the device base plate. The filament can be made of any material, such as metal, organic, or inorganic.

[0009] Preferably, the fixed end of the filament clamp is located outside the moving end of the filament clamp and is fixedly connected to the upper end of the connecting plate.

[0010] Preferably, optical axis fixing plates are fixedly connected to both sides of the upper end of the connecting plate, and the first optical axis and the second optical axis are rotatably connected between the optical axis fixing plates.

[0011] Preferably, nylon foot pads are threaded to the four corners of the lower end of the equipment base plate.

[0012] Preferably, a linear bearing is connected between the first optical axis, the second optical axis, and the moving end of the filament clamp. The second wedge-type bidirectional moving device has a hole in the middle, and a threaded hole located at the upper end of the connecting plate is formed at the lower end of the hole.

[0013] Preferably, the upper end of the filament fixing seat is provided with a threaded hole, the second wedge-type bidirectional moving device is provided with a hole in the middle, and a second threaded hole is provided at the lower end of the hole located at the upper end of the connecting plate.

[0014] Preferably, the upper end of the perforated plate is fixedly connected to the mold top cover, and the upper end of the mold top cover has a casting hole. The perforated plate in the mold area is detachable and adjustable, and can be switched according to the required filament size and spacing.

[0015] Preferably, the dual-track ball screw linear module is driven by a stepper motor.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] Since the mechanical properties of bone tissue are closely related to its anisotropic biomechanical characteristics, this invention, based on the biomimetic model of bone tissue composition and structure, further simulates the stress state of the organic components of bone tissue by adding oriented filaments and applying tensile stress. The recovery stress after stretching will generate compressive stress in the vertical direction, thereby simulating the stress state of the inorganic components. Simultaneously, by adjusting the arrangement of the organic components, the stress state on different components can be controlled, thus achieving precise matching of the mechanical properties of bone tissue in different locations. A stepper motor is used to achieve fixed displacement movement of the filaments, thereby precisely applying tension to each filament while ensuring that the filaments bear tensile stress and the matrix bears compressive stress, achieving the simulation of anisotropic biomechanics of bone tissue based on the biomimetic model of composition and structure. Attached Figure Description

[0018] Figure 1 The three-dimensional structure of the device of the present invention Figure 1 ;

[0019] Figure 2 The three-dimensional structure of the device of the present invention Figure 2 ;

[0020] Figure 3 This is a split view of the perforated plate, mold top cover, and mold base of the present invention;

[0021] Figure 4 This is a structural diagram of the mold top cover of the device of the present invention;

[0022] Figure 5 This is a three-dimensional structural diagram of the perforated plate of the device of the present invention;

[0023] Figure 6 This is a perspective structural diagram of the connecting plate of the device of the present invention;

[0024] Figure 7This is a perspective structural diagram of the first and second inclined wedge bidirectional moving devices of the present invention.

[0025] Figure 8 This is a three-dimensional structural diagram of the filament fixing seat of the device of the present invention.

[0026] In the diagram: 1. Double linear guide ball screw linear module; 2. Stepper motor; 10. Double linear guide ball screw; 14. Connecting plate; 1401. Second threaded hole; 15. First wedge-type bidirectional moving device; 16. Fine wire clamp moving end; 17. Second wedge-type bidirectional moving device; 1701. Hole; 18. Fine wire clamp fixing end; 20. Clamp connector; 21. Linear bearing; 22. First optical axis; 23. Optical axis fixing plate; 24. Second optical axis; 26. Opening plate; 27. Mold top cover; 2701. Casting hole; 28. Mold base; 29. ​​Fine wire fixing seat; 2901. Threaded hole; 30. Equipment base plate; 32. Optical axis base; 34. Nylon foot pad. Detailed Implementation

[0027] The following illustrations disclose several embodiments of the present invention. For clarity, many physical details will be described in the following description. However, it should be understood that these physical details are not intended to limit the invention. That is, in some embodiments of the invention, these physical details are not essential. Furthermore, for the sake of simplicity, some conventional structures and components will be shown in the illustrations in a simple schematic manner.

[0028] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0029] like Figure 1-8As shown, a bone tissue biomechanical state simulation device of the present invention includes a first inclined wedge-shaped bidirectional moving device 15, a second inclined wedge-shaped bidirectional moving device 17, a first optical axis 22, a second optical axis 24, a filament fixing seat 29, and a device base plate 30. The upper end of the connecting plate 14 is rotatably connected to the first optical axis 22 and the second optical axis 24. The first optical axis 22 and the second optical axis 24 are slidably connected to the filament clamp moving end 16. The upper end of the device base plate 30 is fixedly connected to the filament fixing seat 29 and the optical axis base 32. There are two sets of optical axis bases 32, and the two sets of optical axis bases 32 are located between the device bases. The upper end of the plate 30 is fixedly connected to the mold base 28, and the mold base 28 is fixedly connected to the perforated plate 26. The inner side of the optical axis base 32 is fixedly connected to the double linear guide ball screw 10. The inner side of the moving end 16 of the fine wire clamp is fixedly connected to the clamp connector 20. The clamp connector 20 is movably connected to the first wedge-type bidirectional moving device 15 and the second wedge-type bidirectional moving device 17. The lower end of the connecting plate 14 is fixedly connected to the moving end of the double linear guide ball screw linear module 1. The fixed end of the double linear guide ball screw linear module 1 is fixedly connected to the equipment base plate 30.

[0030] Furthermore, the fixed end 18 of the filament clamp is fixedly connected to the outer side of the moving end 16 of the filament clamp and to the upper end of the connecting plate 14.

[0031] Furthermore, optical axis fixing plates 23 are fixedly connected to both sides of the upper end of the connecting plate 14, and the first optical axis 22 and the second optical axis 24 are rotatably connected between the optical axis fixing plates 23.

[0032] Furthermore, nylon foot pads 34 are threaded to the four corners of the lower end of the equipment base plate 30.

[0033] Furthermore, a linear bearing 21 is connected between the first optical axis 22, the second optical axis 24 and the moving end 16 of the filament clamp.

[0034] Furthermore, the upper end of the filament fixing seat 29 is provided with a threaded hole 2901. The second wedge-type bidirectional moving device 17 is provided with a hole 1701 in the middle, and a second threaded hole 1401 located on the upper end of the connecting plate 14 is provided at the lower end of the hole 1701.

[0035] Furthermore, the upper end of the perforated plate 26 is fixedly connected to the mold top cover 27, and the upper end of the mold top cover 27 is provided with a casting hole 2701.

[0036] Furthermore, the dual-track ball screw linear module 1 is driven by a stepper motor 2.

[0037] Example 1

[0038] Step 1: Fix the filament (fiber) array

[0039] One end of a 0.2mm diameter titanium wire is fixed with a screw in the corresponding threaded hole 2901 on the wire fixing seat 29. The other end of the wire is passed through the first wedge-type bidirectional moving device 15, the second wedge-type bidirectional moving device 17, the first optical axis 22 and the second optical axis 24 respectively, and through the perforated plate 26 of the mold area. Similarly, it passes through the first optical axis 22, the second optical axis 24 and the first wedge-type bidirectional moving device 15 and the second wedge-type bidirectional moving device 17 in symmetrical parts to reach the wire fixing seat 29 on the other side. The operation is repeated to fix the 9 wires separately, resulting in a 3*3 wire array.

[0040] Step 2: Controlling the stress state of the filament array

[0041] The above-obtained filament array is pre-tensioned: after fixing the filaments, the screws on the second inclined wedge bidirectional moving device 17 are tightened to lock the filament clamp, thus completing the filament locking operation. The stepper motor 2 is controlled to change displacement by 0.05mm in a single operation, thereby achieving precise displacement control of the filaments and realizing stress change of the filaments through displacement change.

[0042] Step 3: Pour the grout, allow it to cure, and then demold.

[0043] The prepared calcium phosphate bone cement slurry is poured through the pouring hole 2701 at the top of the mold cover 27 above the mold area. After it is completely cured, the perforated plate 26 and the mold cover 27 of the mold area are removed to demold the target composite material sample.

[0044] Example 2

[0045] Unlike Example 1, the diameter of the titanium wire is 0.5 mm, and the corresponding aperture size of the perforated plate in the mold area is 0.55 mm, resulting in a 3*4 filament array.

[0046] Example 3

[0047] The difference from Example 1 is that the titanium wire is replaced with a polylactic acid long monofilament with a diameter of 0.15 mm, and the corresponding aperture size of the perforated plate in the mold area is 0.18 mm, resulting in a 3*3 filament array.

[0048] Example 4

[0049] The difference from Example 1 is that the titanium wire was replaced with a 0.3 mm diameter polylactic acid monofilament, resulting in a 3*4 filament array.

[0050] Table 1 compares the flexural strength of Examples 1-4 with that of the fiber-reinforced non-stretch composite material.

[0051]

[0052] As shown in Table 1, compared with composite materials without tension on the filaments, by optimizing the size, spacing, and distribution array parameters of the filaments, and using a stepper motor 2 to achieve fixed displacement movement of the filaments, the tension can be precisely applied to each filament. This ensures that the filaments bear tensile stress and the matrix bears compressive stress, achieving biomimicry of composition and structure, and further simulating the anisotropic biomechanics of bone tissue. The final results show improved bending strength. This device is of great value for simulating the anisotropic biomechanical characteristics of bone tissue and improving the mechanical properties of biomaterials to better adapt them to bone tissue.

[0053] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A device for simulating the biomechanical state of bone tissue, characterized in that, The device includes a first wedge-type bidirectional moving device (15), a second wedge-type bidirectional moving device (17), a first optical axis (22), a second optical axis (24), a filament fixing seat (29), a device base plate (30), and a connecting plate (14). The upper end of the connecting plate (14) is rotatably connected to the first optical axis (22) and the second optical axis (24). The first optical axis (22) and the second optical axis (24) are slidably connected to the moving end (16) of the filament clamp. The upper end of the device base plate (30) is fixedly connected to the filament fixing seat (29) and the optical axis base (32). The optical axis base (32) consists of two sets, and the two sets of optical axis bases (32) are located between the device base plate (30). The upper end of the mold base (28) is fixedly connected to the mold base (28), and the mold base (28) is fixedly connected to the perforated plate (26). The inner side of the optical axis base (32) is fixedly connected to the double linear guide ball screw (10). The inner side of the fine wire clamp moving end (16) is fixedly connected to the clamp connector (20). The clamp connector (20) is movably connected to the first inclined wedge bidirectional moving device (15) and the second inclined wedge bidirectional moving device (17). The lower end of the connecting plate (14) is fixedly connected to the moving end of the double linear guide ball screw linear module (1). The fixed end of the double linear guide ball screw linear module (1) is fixedly connected to the equipment base plate (30). Located outside the moving end (16) of the filament clamp and fixedly connected to the upper end of the connecting plate (14) of the filament clamp (18). The upper end of the filament fixing seat (29) is provided with a threaded hole (2901), the second inclined wedge bidirectional moving device (17) is provided with a hole (1701) in the middle, and a second threaded hole (1401) is provided at the lower end of the hole (1701) located at the upper end of the connecting plate (14). The upper end of the perforated plate (26) is fixedly connected to the mold top cover (27), and the upper end of the mold top cover (27) is provided with a pouring hole (2701). The dual-track ball screw linear module (1) is driven by a stepper motor (2); One end of the filament is fixed in the corresponding threaded hole (2901) on the filament fixing seat (29) by a screw. The other end of the filament is passed through the first inclined wedge bidirectional moving device (15), the second inclined wedge bidirectional moving device (17), the first optical axis (22) and the second optical axis (24) respectively, and passes through the opening plate (26) of the mold area. Similarly, it passes through the first optical axis (22), the second optical axis (24) and the first inclined wedge bidirectional moving device (15) and the second inclined wedge bidirectional moving device (17) of the symmetrical part in sequence to reach the filament fixing seat (29) on the other side. The operation is repeated to complete the fixing of the filaments separately and obtain the filament array. The above-obtained filament array is pre-tensioned. After fixing the filament, the screw on the second inclined wedge bidirectional moving device (17) is tightened to lock the filament clamp, thus completing the filament locking operation. The displacement of the stepper motor (2) is controlled to achieve precise displacement control of the filament. The stress change of the filament is achieved through displacement change. The prepared calcium phosphate bone cement slurry is poured through the pouring hole (2701) at the top of the mold top cover (27) above the mold area. After it is completely cured, the perforated plate (26) and the mold top cover (27) of the mold area are removed to demold the target composite material sample.

2. The bone tissue biomechanical state simulation device according to claim 1, characterized in that: The upper end of the connecting plate (14) is fixedly connected to the optical axis fixing plate (23) on both sides, and the optical axis fixing plate (23) is rotatably connected to the first optical axis (22) and the second optical axis (24).

3. The bone tissue biomechanical state simulation device according to claim 1, characterized in that: The bottom of the equipment base plate (30) is threaded with nylon foot pads (34) at the four corners.

4. The bone tissue biomechanical state simulation device according to claim 1, characterized in that: A linear bearing (21) is connected between the first optical axis (22), the second optical axis (24) and the moving end (16) of the filament clamp.

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