External fixation device for preparing mouse bone defect model
By designing a multi-point fixation device with an Ω-shaped frame and a lock, the problem of fixation instability in a mouse bone defect model was solved, achieving stability and precise connection of fractured bones and promoting bone repair.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 山西医科大学第二医院(山西医科大学第二临床医学院)
- Filing Date
- 2025-02-26
- Publication Date
- 2026-06-19
AI Technical Summary
Existing fixation devices for mouse bone defect models suffer from problems such as trauma, bone loss, difficulty in operation, fracture splitting, and unstable fixation, especially when the mouse skeleton is thin and difficult to fix effectively.
An external fixation device including an Ω-shaped frame and a locker is designed. The clamping arms of the Ω-shaped frame and the locker are used to fix mouse bone fractures at multiple points. Wrap-like fixation is achieved through structures such as clamping arm rings, flexible pads and bolts to ensure that the bone fractures do not shift during the repair process.
It improves the fixation stability of the mouse bone defect model, ensures that the broken bone does not shift during the repair process, and promotes the precision of bone connection and healing.
Smart Images
Figure CN224370029U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of fixation of mouse bone fractures or bone defects, and more specifically, it relates to an external fixation device for preparing mouse bone fracture or bone defect models. Background Technology
[0002] Mouse fracture or bone defect models are commonly used animal models for research in bone regeneration, bone repair, orthopedic diseases, and biomaterials. However, existing fixation devices for mouse defect models can lead to partial bone loss due to trauma or treatment, loosening and dislodgement of internal fixation, operational difficulties, and intraoperative fracture splitting, posing challenges to experimental procedures. Exploring new treatment options for basic research is a hot topic in this field. Traditional external fixators used in bone defect models, such as CN110772308A and CN110301993A, involve vertically inserting short pins into the rat femur for fixation. The disadvantages include damage to intramedullary tissue via the pin channel, interfering with blood supply and affecting the integrity of bone sections. Furthermore, this approach is difficult to operate in mice due to their slender skeletons. The external fixator designed in CN219375022U is used for traction of bone defects, but its problems include a single stress point at the femoral fixation point, structural instability, and inability to stably fix the defect ends during movement after the mouse recovers from anesthesia.
[0003] Therefore, in view of this, we have studied and improved the existing structure and its deficiencies, and provided an external fixation device for preparing a mouse bone defect model, in order to achieve a more practical purpose. Utility Model Content
[0004] This invention provides an external fixation device for preparing a mouse bone defect model, which overcomes the above-mentioned defects in the prior art.
[0005] The purpose and effectiveness of this utility model's external fixation device for preparing mouse bone defect models are achieved through the following specific technical means:
[0006] An external fixation device for preparing a mouse bone defect model includes: an Ω-shaped frame and locking devices, wherein the Ω-shaped frame has an opening between its two ends, two locking devices are respectively connected to the two ends of the Ω-shaped frame and a space for free movement is formed between the two locking devices, the locking devices are hidden inside the mouse body and fix two fractured bones, and the Ω-shaped frame is exposed outside the mouse body.
[0007] In a further technical solution, the Ω-shaped frame has two clamping arms and one connecting arm. The connecting arm is disposed between the two clamping arms, and one end of each of the two clamping arms is fixedly connected to the connecting arm. The corners where the clamping arms and the connecting arm are connected are rounded. The free ends of the two clamping arms are close to each other, and the free ends of the clamping arms are fixedly connected to the locking device.
[0008] In a further technical solution, the locker is a rectangular plate with four through holes for locking onto the bone. The sides of the two rectangular plates that are close to each other are the inner wall surfaces, and the sides of the two rectangular plates that are far apart from each other are the outer wall surfaces. The outer wall surfaces protrude from the outer surface of the clamping arm, and the inner wall surfaces protrude from the inner surface of the clamping arm.
[0009] A further technical solution includes a first clamping arm and a second clamping arm, and an external fixing device including a sliding frame and a central fixed clamping arm. One end of the first clamping arm is connected to the sliding frame, and the second clamping arm is slidably disposed on the inner side of the sliding frame. A central fixed clamping arm is connected between the second clamping arm and the first clamping arm. The locking device is a clamping arm ring, and the other end of the first clamping arm is connected to the clamping arm ring. The clamping arm ring includes a first clamping arm ring and a movable clamping arm assembly. One end of the first clamping arm ring is fixedly connected to the end of the first clamping arm, and the other end of the first clamping arm ring is provided with a fixing groove. The free end of the movable clamping arm assembly can be locked in the fixing groove. The movable clamping arm assembly includes a movable clamping arm ring body, a flexible pad, and a fixing plate. One end of the movable clamping arm ring body is connected to the fixing plate. The inner side of the movable clamping arm ring body is provided with a plurality of flexible pads, which are arranged in a ring and spaced apart.
[0010] In a further technical solution, the ends of the first clamping arm and the second clamping arm are provided with limiting grooves, the end of the fixing plate is inserted into the limiting groove, and the other end of the movable clamping arm ring is fixed inside the fixing groove.
[0011] In a further technical solution, the side of the sliding frame is provided with a movable groove, the other side surface of the sliding frame is provided with a threaded hole, and a second clamping arm is slidably disposed inside the movable groove.
[0012] In a further technical solution, a first fastening bolt is rotatably provided inside the threaded hole, and the first fastening bolt is used to fix the second clamping arm.
[0013] A further technical solution is provided, wherein the central fixed clamping arm includes a crossbar, a support rod, a through-hole ring, and a central fixed cylinder. The support rod is connected to the outer side of the crossbar, and the through-hole ring is fixedly connected to the end of the support rod. The central fixed cylinder is installed on the inner side of the through-hole ring, and a second fastening bolt is provided on the outer side of the through-hole ring. The second fastening bolt fastens and locks the central fixed cylinder.
[0014] In a further technical solution, a second clamping arm ring is fixedly connected to the end of the second clamping arm. A plurality of flexible pads are arranged in an annular array on the inner side of the second clamping arm ring. A plurality of circular protrusions are arranged on the surface of the flexible pads. A gap is provided between the plurality of circular protrusions. The plurality of circular protrusions are arranged in an annular pattern.
[0015] In a further technical solution, the upper surfaces of both the first clamping arm and the second clamping arm are provided with threaded grooves, and the threaded grooves are in communication with the interior of the limiting groove.
[0016] In a further technical solution, the first clamping arm and the second clamping arm are each provided with a telescopic groove on the opposite side, and the crossbar is slidably connected in the telescopic groove.
[0017] In a further technical solution, the second clamping arm ring and the movable clamping arm assembly close to form an annular groove. The first clamping arm and the second clamping arm have the same end structure, and the first clamping arm ring and the corresponding movable clamping arm assembly also close to form the annular groove.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] This invention discloses an external fixation device for preparing a mouse bone defect model. The device comprises a first clamping arm, a second clamping arm, and a central fixing clamping arm. The mouse bone fragment is removed, and the central bone fragment is placed inside the central fixing cylinder. A second fastening bolt is then used to fix the bone fragment. Next, the first clamping arm ring is placed on the right side of the mouse bone fragment, ensuring the fragment penetrates the annular groove. After installation, it is checked whether the first clamping arm ring and the movable clamping arm assembly provide a wrapping fixation to the end of the right side bone fragment. After verification, a bolt is used for penetration fixation. Once the right side bone fragment is fixed, the second clamping arm is installed in the movable groove. Then, the second clamping arm ring at the end of the second clamping arm and the movable clamping arm assembly are used in the same fixing method to fix the left side bone fragment. After the left and right sides are secured, the crossbar of the middle fixing arm is inserted into the telescopic groove. Then, the second clamping arm is moved inward, so that the first clamping arm, the middle fixing arm, and the second clamping arm are in the same horizontal position, and the left, middle, and right fracture bones are all connected. By gradually securing the left, middle, and right fracture bones, and ensuring that a wrapping fixation is used in each step, the fracture bones are kept in the same horizontal position. Multi-point fixation ensures that the bones will not shift during the repair process, improving stability. Furthermore, through the mobility of the second clamping arm and the cooperation of the first clamping arm, the middle fixing arm, etc., the position can be finely adjusted throughout the fixation process, making the bone connection more precise and facilitating repair and healing. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the overall appearance structure of the first embodiment of this utility model;
[0021] Figure 2 This is a schematic diagram of the overall front view of the first embodiment of this utility model;
[0022] Figure 3 This is a schematic diagram of the overall structure of the second embodiment of this utility model;
[0023] Figure 4 This is a front view structural diagram of the second embodiment of the present invention;
[0024] Figure 5 This is a schematic diagram of the overall structure of the first clamping arm 11 and the second clamping arm 12 in this utility model;
[0025] Figure 6 This is a partial structural schematic diagram of the first clamping arm 11 and the second clamping arm 12 in this utility model;
[0026] Figure 7 This is a schematic diagram of the overall structure of the movable clamping arm assembly 20 in this utility model;
[0027] Figure 8 This is a schematic diagram of the overall structure of the central fixed clamping arm 14 in this utility model;
[0028] Figure 9 This is a schematic diagram of the overall side view structure of this utility model;
[0029] Figure 10 This is a utility model Figure 9 Enlarged structural diagram at point A in the diagram;
[0030] Figure 11 This is a utility model Figure 10 Enlarged structural diagram at point B in the diagram;
[0031] Figure 12 This is a utility model Figure 6 A magnified structural diagram at point C in the diagram.
[0032] Explanation of reference numerals in the attached figures:
[0033] First clamping arm 11, second clamping arm 12, sliding frame 13, middle fixed clamping arm 14, threaded hole 15, clamping arm ring 16, telescopic groove 17, first clamping arm ring 18, second clamping arm ring 19, movable clamping arm assembly 20, first fastening bolt 21, movable groove 22, crossbar 23, limiting groove 24, fixing plate 25, flexible pad 26, support rod 27, through hole ring 28, second fastening bolt 29, middle fixed cylinder 30, annular groove 31, circular protrusion 32, threaded groove 33, fixing groove 34, movable clamping arm ring body 35, rectangular plate 41, through hole 42, outer facade 43, inner facade 44, outer wall surface 45, inner wall surface 46, clamping arm 47, connecting arm 48. Detailed Implementation
[0034] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.
[0035] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0036] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0037] Example 1: As shown in the attached document Figure 1 To be continued Figure 2 As shown:
[0038] This invention provides an external fixation device for preparing a mouse bone defect model.
[0039] See attached document Figure 11 To be continued Figure 12The device includes an Ω-shaped frame and locking devices. The Ω-shaped frame has an opening between its two ends. Two locking devices are respectively connected to the two ends of the Ω-shaped frame, and an open space for air-cushioning is formed between the two locking devices. The locking devices are hidden inside the mouse and fix two broken bones. The Ω-shaped frame is exposed outside the mouse.
[0040] See attached document Figure 1 To be continued Figure 2 The Ω-shaped frame has two clamping arms 47 and one connecting arm 48. The connecting arm 48 is disposed between the two clamping arms 47, and one end of each of the two clamping arms 47 is fixedly connected to the connecting arm 48. The corners where the clamping arms 47 and the connecting arm 48 are connected are rounded. The free ends of the two clamping arms 47 are close to each other, and the free ends of the clamping arms 47 are fixedly connected to the locking device.
[0041] See attached document Figure 1 To be continued Figure 2 The locking device is a rectangular plate 41 with four through holes 42 for locking to the bone. The sides of the two rectangular plates 41 that are close to each other are the inner wall surface 46, and the sides of the two rectangular plates 41 that are far apart from each other are the outer wall surface 45. The outer wall surface 45 protrudes from the outer surface 43 of the clamping arm 47, and the inner wall surface 46 protrudes from the inner surface 44 of the clamping arm 47.
[0042] Example 2: As shown in the attached document Figure 3 To be continued Figure 12 As shown:
[0043] This invention provides an external fixation device for preparing a mouse bone defect model.
[0044] See attached document Figure 3 To be continued Figure 12The device includes: the Ω-shaped frame includes a first clamping arm 11 and a second clamping arm 12; the external fixing device further includes a sliding frame 13 and a central fixing clamping arm 14; one end of the first clamping arm 11 is connected to the sliding frame 13; the second clamping arm 12 is slidably disposed on the inner side of the sliding frame 13; the central fixing clamping arm 14 is connected between the second clamping arm 12 and the first clamping arm 11; the locking device is a clamping arm ring 16; the other end of the first clamping arm 11 is connected to the clamping arm ring 16; the clamping arm ring 16 includes a first clamping arm ring 18 and a movable clamping arm assembly 20; the first clamping arm ring 18... One end of the arm ring 18 is fixedly connected to the end of the first clamping arm 11. The other end of the first clamping arm ring 18 is provided with a fixing groove 34. The free end of the movable clamping arm assembly 20 can be locked in the fixing groove 34. The movable clamping arm assembly 20 includes a movable clamping arm ring body 35, a flexible pad 26, and a fixing plate 25. One end of the movable clamping arm ring body 35 is connected to the fixing plate 25. The inner side of the movable clamping arm ring body 35 is provided with a plurality of flexible pads 26. The plurality of flexible pads 26 are arranged in a ring and there is a gap between the plurality of flexible pads 26.
[0045] Preferred options are shown in the appendix. Figure 6 and appendix Figure 7 The ends of the first clamping arm 11 and the second clamping arm 12 are provided with limiting grooves 24. The end of the fixing plate 25 is inserted into the limiting groove 24, and the other end of the movable clamping arm ring 35 is fixed inside the fixing groove 34.
[0046] Preferred options are shown in the appendix. Figure 6 The sliding frame 13 has a movable groove 22 on one side and a threaded hole 15 on the other side surface. A second clamping arm 12 is slidably disposed inside the movable groove 22.
[0047] Preferred options are shown in the appendix. Figure 6 A first fastening bolt 21 is rotatably provided inside the threaded hole 15, and the first fastening bolt 21 is fixedly connected to the second clamping arm 12.
[0048] Preferred options are shown in the appendix. Figure 8 The central fixed clamping arm 14 includes a crossbar 23, a support rod 27, a through-hole ring 28, and a central fixed cylinder 30. The support rod 27 is connected to the outer side of the crossbar 23. The through-hole ring 28 is fixedly connected to the end of the support rod 27. The central fixed cylinder 30 is installed on the inner side of the through-hole ring 28. A second fastening bolt 29 is provided on the outer side of the through-hole ring 28. The second fastening bolt 29 fastens and locks the central fixed cylinder 30.
[0049] Preferred options are shown in the appendix. Figure 10 and appendix Figure 11The second clamping arm 12 is fixedly connected to a second clamping arm ring 19. The inner side of the second clamping arm ring 19 is also provided with a plurality of flexible pads 26 arranged in a ring. The surface of the flexible pads 26 is provided with a plurality of circular protrusions 32 arranged in a ring. There are gaps between the plurality of circular protrusions 32. The plurality of circular protrusions 32 are arranged in a ring.
[0050] Preferred options are shown in the appendix. Figure 5 The upper surfaces of the first clamping arm 11 and the second clamping arm 12 are provided with threaded grooves 33, and the threaded grooves 33 are in communication with the interior of the limiting groove 24.
[0051] Preferred options are shown in the appendix. Figure 6 and appendix Figure 8 The first clamping arm 11 and the second clamping arm 12 are each provided with a telescopic groove 17 on the opposite side, and the crossbar 23 is slidably connected in the telescopic groove 17.
[0052] Preferred options are shown in the appendix. Figure 9 The second clamping arm ring 19 and the movable clamping arm assembly 20 close to form an annular groove 31. The first clamping arm 11 and the second clamping arm 12 have the same end structure. The first clamping arm ring 18 and the corresponding movable clamping arm assembly 20 also close to form the annular groove 31.
[0053] Specific usage method of this utility model:
[0054] When using this invention, first disinfect it, then anesthetize the mouse, prepare and disinfect the skin on the outer side of the femur, cut the skin along the long axis of the femur, and bluntly separate the soft tissue around the mouse femur with scissors.
[0055] The mouse's broken bone was then removed, and the middle part of the broken bone was placed inside the middle fixing cylinder 30. The second fastening bolt 29 was then used to fix the broken bone. The first clamping arm ring 18 was then placed on the right side of the broken bone, ensuring that the broken bone penetrated into the annular groove 31. After installation, it was checked whether the first clamping arm ring 18 and the movable clamping arm assembly 20 provided a wrapping fixation to the end of the right side of the broken bone. After the check was completed, the bolt was used for penetration fixation. After the right side of the broken bone was fixed, the second clamping arm 12 was installed in the movable groove 22. Then, the second clamping arm ring 19 at the end of the second clamping arm 12 and the movable clamping arm assembly 20 were fixed to the left side of the broken bone using the same fixation method.
[0056] After the left and right sides are fixed, the crossbar 23 of the middle fixing arm 14 is inserted into the telescopic groove 17. Then the position of the second clamping arm 12 is moved inward, and the first clamping arm 11, the middle fixing arm 14 and the second clamping arm 12 are in the same horizontal position, and the left fracture bone, the middle fracture bone and the right fracture bone are all connected.
[0057] After determining the position of the second clamping arm 12, the position of the second clamping arm 12 is fixed by passing the first fastening bolt 21 through the threaded hole 15. Then the wound is disinfected and sutured layer by layer.
[0058] This invention discloses an external fixation device for preparing a mouse bone defect model. The device comprises a first clamping arm, a second clamping arm, and a central fixing clamping arm. The mouse bone fragment is removed, and then the central bone fragment is placed inside the central fixing cylinder. A second fastening bolt is then used to fix the bone fragment. Next, the first clamping arm ring is placed on the right side of the mouse bone fragment, ensuring the fragment penetrates the annular groove. After installation, it is checked whether the first clamping arm ring and the movable clamping arm assembly provide a wrapping fixation to the end of the right side bone fragment. After inspection, a bolt is used for penetration fixation. Once the right side bone fragment is fixed, the second clamping arm is installed on the movable clamping arm. Within the movable groove, the second clamping arm ring at the end of the second clamping arm and the movable clamping arm assembly are then fixed to the fractured bone on the left side of the mouse using the same fixing method. After both the left and right sides are fixed, the crossbar on the middle fixing clamping arm is inserted into the telescopic groove. The position of the second clamping arm is then moved inward, aligning the first clamping arm, the middle fixing clamping arm, and the second clamping arm at the same horizontal level, ensuring that the fractured bones on the left, middle, and right sides are all connected. By progressively fixing the fractured bones on the left, middle, and right sides, and ensuring that a wrap-around fixation is used in each step, the fractured bones are kept in the same horizontal position. This multi-point fixation ensures that the bone does not shift during the repair process, improving stability. Furthermore, through the mobility of the second clamping arm and the coordination of the first clamping arm, the middle fixing clamping arm, etc., the position can be finely adjusted throughout the fixation process, making the bone connection more precise and facilitating repair and healing.
[0059] The embodiments of this utility model are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the utility model to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical applications of this utility model, and to enable those skilled in the art to understand this utility model and design various embodiments with various modifications suitable for a particular purpose.
Claims
1. An external fixation device for preparing a mouse bone defect model, characterized in that: The device includes an Ω-shaped frame and locking devices. The Ω-shaped frame has an opening between its two ends. Two locking devices are respectively connected to the two ends of the Ω-shaped frame, and an open space for air-cushioning is formed between the two locking devices. The locking devices are hidden inside the mouse and fix two broken bones. The Ω-shaped frame is exposed outside the mouse.
2. The external fixation device for preparing a mouse bone defect model according to claim 1, characterized in that, The Ω-shaped frame has two clamping arms (47) and one connecting arm (48). The connecting arm (48) is disposed between the two clamping arms (47), and one end of each of the two clamping arms (47) is fixedly connected to the connecting arm (48). The corners where the clamping arms (47) and the connecting arm (48) are connected are rounded. The free ends of the two clamping arms (47) are close to each other, and the free ends of the clamping arms (47) are fixedly connected to the locking device.
3. The external fixation device for preparing a mouse bone defect model according to claim 2, characterized in that, The locking device is a rectangular plate (41) with four through holes (42) for locking to the bone. The sides of the two rectangular plates (41) that are close to each other are the inner wall surfaces (46), and the sides of the two rectangular plates (41) that are far apart from each other are the outer wall surfaces (45). The outer wall surfaces (45) protrude from the outer facade (43) of the clamping arm (47), and the inner wall surfaces (46) protrude from the inner facade (44) of the clamping arm (47).
4. The external fixation device for preparing a mouse bone defect model according to claim 1, characterized in that, The Ω-shaped frame includes a first clamping arm (11) and a second clamping arm (12). The external fixing device also includes a sliding frame (13) and a middle fixing clamping arm (14). One end of the first clamping arm (11) is connected to the sliding frame (13). The second clamping arm (12) is slidably disposed on the inner side of the sliding frame (13). The middle fixing clamping arm (14) is connected between the second clamping arm (12) and the first clamping arm (11). The locking device is a clamping arm ring (16). The other end of the first clamping arm (11) is connected to the clamping arm ring (16). The clamping arm ring (16) includes a first clamping arm ring (18) and a movable clamping arm assembly (20). One end of the ring (18) is fixedly connected to the end of the first clamping arm (11). The other end of the first clamping arm ring (18) is provided with a fixing groove (34). The free end of the movable clamping arm assembly (20) can be locked in the fixing groove (34). The movable clamping arm assembly (20) includes a movable clamping arm ring body (35), a flexible pad (26), and a fixing plate (25). One end of the movable clamping arm ring body (35) is connected to the fixing plate (25). The inner side of the movable clamping arm ring body (35) is provided with a plurality of flexible pads (26). The plurality of flexible pads (26) are arranged in a ring, and there is a gap between the plurality of flexible pads (26).
5. The external fixation device for preparing a mouse bone defect model according to claim 4, characterized in that: The ends of the first clamping arm (11) and the second clamping arm (12) are provided with limiting grooves (24), the end of the fixing plate (25) is inserted into the limiting groove (24), and the other end of the movable clamping arm ring (35) is fixed inside the fixing groove (34).
6. The external fixation device for preparing a mouse bone defect model according to claim 5, characterized in that: The sliding frame (13) has a movable groove (22) on its side and a threaded hole (15) on the other side surface of the sliding frame (13). A second clamping arm (12) is slidably disposed inside the movable groove (22).
7. The external fixation device for preparing a mouse bone defect model according to claim 6, characterized in that: The threaded hole (15) is rotatably provided with a first fastening bolt (21), which is used to fix the second clamping arm (12).
8. The external fixation device for preparing a mouse bone defect model according to claim 7, characterized in that: The central fixed clamping arm (14) includes a crossbar (23), a support rod (27), a through-hole ring (28), and a central fixed cylinder (30). The support rod (27) is connected to the outer side of the crossbar (23). The through-hole ring (28) is fixedly connected to the end of the support rod (27). The central fixed cylinder (30) is installed on the inner side of the through-hole ring (28). The second fastening bolt (29) is provided on the outer side of the through-hole ring (28). The second fastening bolt (29) fastens and locks the central fixed cylinder (30).
9. The external fixation device for preparing a mouse bone defect model according to claim 8, characterized in that: The second clamping arm (12) is fixedly connected to a second clamping arm ring (19). The inner side of the second clamping arm ring (19) is provided with a plurality of flexible pads (26) arranged in an annular array. The surface of the flexible pads (26) is provided with a plurality of circular protrusions (32). There are gaps between the plurality of circular protrusions (32). The plurality of circular protrusions (32) are arranged in an annular pattern.
10. The external fixation device for preparing a mouse bone defect model according to claim 9, characterized in that: The upper surfaces of the first clamping arm (11) and the second clamping arm (12) are provided with threaded grooves (33), and the threaded grooves (33) are in communication with the interior of the limiting groove (24).
11. The external fixation device for preparing a mouse bone defect model according to claim 10, characterized in that: The first clamping arm (11) and the second clamping arm (12) are each provided with a telescopic groove (17) on the opposite side, and the crossbar (23) is slidably connected in the telescopic groove (17).
12. The external fixation device for preparing a mouse bone defect model according to claim 11, characterized in that: The second clamping arm ring (19) and the movable clamping arm assembly (20) close to form an annular groove (31). The first clamping arm (11) and the second clamping arm (12) have the same end structure. The first clamping arm ring (18) and the corresponding movable clamping arm assembly (20) also close to form the annular groove (31).