Tension band kirschner wire guide assembly for ulna olecranal fracture

Abstract

The invention relates to the technical field of orthopedic instruments, in particular to a tension band kirschner wire guide assembly for ulna olecranal fracture. Comprising an attaching plate capable of being attached to the back side of the olecranon of the ulna, an angle adjusting mechanism is installed on the arc face of the attaching plate, two parallel guide cylinders are installed on the angle adjusting mechanism, and the angle adjusting mechanism can adjust the angle between the guide cylinders and the tangent line of the back side of the olecranon of the ulna. The angle adjusting mechanism comprises a fixing plate, a driving device and two same transmission gears; the axes of the two transmission gears are rotationally connected with the fixing plate, the two transmission gears are meshed with each other, the two ends of a rotating shaft of one transmission gear are fixedly connected with the outer side walls of the two guide cylinders correspondingly, and the other transmission gear is meshed with the driving device; two parallel through grooves are formed in the positions, located on the guide cylinders, of the attaching plate. The guiding assembly can accurately control the needle inserting point and the needle inserting angle of the kirschner wire on the olecranon, and the risk that the kirschner wire penetrates through an articular cavity can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of orthopedic instruments, and in particular, to a tension band Kirschner wire guiding assembly for olecranon fractures of the ulna. Background Art

[0002] Olecranon fractures of the ulna are common traumas of the elbow joint, mostly caused by direct violence or strong contraction of the triceps brachii during a fall. Traditional treatment methods include plaster fixation, internal fixation with plates and screws, and tension band fixation techniques. Among them, tension band fixation has become a commonly used clinical procedure because it conforms to the biomechanical principle (converting tensile force into compressive stress) and is easy to operate.

[0003] In the prior art, the standardized operation of tension band fixation is first to expose the fracture site through a posterior incision, temporarily fix it with a reduction forceps after cleaning the soft tissues to ensure anatomical reduction of the articular surface; secondly, drill two Kirschner wires with a diameter of 2.0 - 2.5 mm in parallel, penetrating the anterior cortex of the ulna to enhance the anchoring effect; finally, use the "8" - shaped winding method to pass the wire through the distal ends of the Kirschner wires and the distal bone holes, and gradually tighten to achieve dynamic compression.

[0004] Among them, when drilling the Kirschner wires, to avoid the risk of the Kirschner wires penetrating the joint cavity, Turkish scientists measured the anatomical landmarks of the dorsal cortex of the olecranon (including the central height of the crescent - shaped incision, the tubercle angle, etc.), and simulated the joint penetration risks at different needle - entry positions (0, 5, 8 mm). It was found that when the safe needle - entry point is 5 mm in front of the dorsal cortex of the olecranon process and the angle with the dorsal cortex is ≤20°, the probability of the Kirschner wire penetrating the joint cavity is the lowest. However, in actual clinical operations, medical staff control the needle - entry point and the needle - entry angle of the Kirschner wire based on clinical experience. For medical staff with insufficient experience, it is easy for the tip of the Kirschner wire to break through the olecranon joint surface, causing the risks of cartilage damage and postoperative arthritis.

[0005] Therefore, in view of the above problems, the applicant invented a tension band Kirschner wire guiding assembly for olecranon fractures of the ulna that can accurately adjust the needle - entry point and the needle - entry angle of the Kirschner wire. Summary of the Invention

[0006] The purpose of the present invention is to provide a tension band Kirschner wire guiding assembly for olecranon fractures of the ulna, which can accurately control the needle - entry point and the needle - entry angle of the Kirschner wire in the olecranon of the ulna and avoid the risk of the Kirschner wire penetrating the joint cavity.

[0007] The present invention is realized as follows. A tension band Kirschner wire guiding assembly for olecranon fractures of the ulna includes a fitting plate that can be attached to the dorsal side of the olecranon process of the ulna. An angle - adjusting mechanism is installed on the arc surface of the fitting plate, and two parallel guiding cylinders are installed on the angle - adjusting mechanism. The angle - adjusting mechanism can adjust the angle between the guiding cylinder and the tangent line of the dorsal side of the olecranon process of the ulna.

[0008] Further, the angle adjustment mechanism is three groups of through holes with different angles and penetrating the fitting plate, and the number of through holes in each group is two; the two guide cylinders are detachably connected to one group of through holes.

[0009] Further, the angle adjustment mechanism includes a fixing plate, a driving device and two identical transmission gears; the axles of the two transmission gears are rotatably connected to the fixing plate, the two transmission gears mesh with each other, the two ends of the rotating shaft of one of the transmission gears are respectively fixedly connected to the outer side walls of the two guide cylinders, and the other transmission gear meshes with the driving device; two parallel through grooves are formed in the fitting plate at the position of the guide cylinder.

[0010] Further, the driving device includes a rack, a slider and a limiting block; a vertical sliding groove is formed on the back side of the fitting plate, and a plurality of limiting grooves are formed on one side of the sliding groove; the rack meshes with the transmission gear, the end of the rack is fixedly connected to the slider, the limiting block is slidably arranged on the surface of the slider, and the limiting block can horizontally move into the limiting groove.

[0011] Further, the driving device includes a worm, two meshing bevel gears and a knob one; the worm meshes with the transmission gear, a rotating chamber is formed in the fitting plate, the two bevel gears are both located in the rotating chamber, and the axles are respectively fixedly connected to the end of the worm and the knob one.

[0012] Further, the driving device is a knob two, and the rotating shaft of the knob two is fixedly connected to the axle center of the transmission gear.

[0013] Further, an angle measuring device is installed on the fixing plate; the angle measuring device includes a protractor and a pointer; the protractor is arranged on the fixing plate, one end of the pointer is fixedly installed on the axle center of the transmission gear meshing with the driving device, the other end of the pointer points to the scale of the protractor, the pointer is arranged in parallel with the guide cylinder; the 0 scale line of the protractor is arranged in parallel with the driving device.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. Install the angle adjustment mechanism on the fitting plate, and then fixedly install the two parallel guide cylinders on the angle adjustment mechanism, so that the two Kirschner wires can be drilled into the ulna along a specified angle according to the fracture condition of the olecranon of the ulna, realizing the fixation of the fractured ulna, and at the same time, it can also avoid the Kirschner wire penetrating the joint cavity;

[0016] 2. Fix the two ends of the rotating shaft of the transmission gear to the two guide cylinders respectively, and drive the transmission gear to rotate by meshing the rack with the transmission gear, so as to adjust the angle of the guide cylinder, which can not only steplessly adjust the rotation angle of the guide cylinder, but also improve the practicability of the device;

[0017] 3. Mesh the worm with the transmission gear. By driving the rotation of the worm to adjust the angle of the guiding cylinder, not only can the stepless adjustment of the angle at which the Kirschner wire penetrates the olecranon of the ulna be achieved, but also self-locking can be realized. After the guiding cylinder rotates to the specified angle, there is no need for fixation, which is convenient for medical staff to perform subsequent operations.

[0018] 4. Set a protractor on the fixing plate and a pointer on the rotating shaft of the transmission gear. The pointer points to the scale of the protractor. At the same time, the 0 scale line of the protractor is parallel to the vertical direction of the driving device, and the pointer is parallel to the guiding cylinder. In this way, when the medical staff adjusts the angle of the guiding cylinder, they can always know the included angle between the guiding cylinder and the dorsal tangent of the olecranon process of the ulna, so as to effectively avoid the Kirschner wire penetrating the joint cavity.

[0019] 5. The connection line between the end of the through groove close to the driving device and the rotation axis of the guiding cylinder is parallel to the vertical direction of the driving device. In this way, by fixing the length value of the through groove, the maximum included angle between the guiding cylinder and the dorsal tangent of the olecranon process of the ulna can be fixed. In this way, no matter from which angle the medical staff drills the Kirschner wire into the olecranon of the ulna, the Kirschner wire can be prevented from penetrating the joint cavity. Description of the Drawings

[0020] Figure 1 is a side cross-sectional view of a tension band Kirschner wire guiding assembly for olecranon fracture of the ulna provided in Embodiment 1 of the present invention;

[0021] Figure 2 is a front view of a tension band Kirschner wire guiding assembly for olecranon fracture of the ulna provided in Embodiment 1 of the present invention;

[0022] Figure 3 is a schematic diagram of the use of a tension band Kirschner wire guiding assembly for olecranon fracture of the ulna provided in Embodiment 1 of the present invention;

[0023] Figure 4 is a side cross-sectional view of a tension band Kirschner wire guiding assembly for olecranon fracture of the ulna without the fixing plate provided in Embodiment 2 of the present invention;

[0024] Figure 5 is a side cross-sectional view of a tension band Kirschner wire guiding assembly for olecranon fracture of the ulna provided in Embodiment 2 of the present invention;

[0025] Figure 6 is Figure 5 the enlarged view of part A in

[0026] Figure 7 is the schematic diagram of the principle for measuring the included angle between the Kirschner wire and the dorsal tangent of the olecranon process when the Kirschner wire penetrates the ulna in Embodiment 2 of the present invention (point O is the rotation center point of the guiding cylinder);

[0027] Figure 8It is the front view of a tension band Kirschner wire guiding assembly for olecranon fracture in Embodiment 2 of the present invention;

[0028] Figure 9 It is the side sectional view of a tension band Kirschner wire guiding assembly for olecranon fracture provided in Embodiment 4 of the present invention;

[0029] Figure 10 It is the front view of a tension band Kirschner wire guiding assembly for olecranon fracture provided in Embodiment 4 of the present invention;

[0030] Figure 11 It is the front view of a tension band Kirschner wire guiding assembly for olecranon fracture provided in Embodiment 5 of the present invention.

[0031] The reference signs involved in the above-mentioned drawings:

[0032] 1, fitting plate; 2, guiding cylinder; 3, through hole; 4, Kirschner wire; 5, olecranon; 6, through groove; 7, sliding groove; 8, limiting block; 9, slider; 10, rack; 11, driving gear; 12, fixing plate; 13, pointer; 14, protractor; 15, limiting groove; 16, rotating chamber; 17, knob one; 18, bevel gear; 19, worm; 20, knob two. Detailed implementation manners

[0033] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0034] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0035] In the drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and cannot be understood as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0036] Refer to Figures 1-11 as shown, which is the preferred embodiment provided by the present invention.

[0037] Embodiment 1: A tension band Kirschner wire guiding assembly for olecranon fracture, such as Figures 1-3As shown, it includes a bonding plate 1 that can be bonded to the dorsal side of the olecranon 5 of the ulna. An angle adjustment mechanism is provided on the curved surface of the bonding plate 1. The adjustment mechanism of this embodiment is three groups of through holes 3, such as Figure 2 As shown, each group is 2. A thread is provided in the through hole 3, and the guide assembly also includes two identical guide cylinders 2, and the outer side wall of the guide cylinder 2 is provided with an external thread. When in use, the two guide cylinders 2 are installed on the two through holes 3 of the same group, and the Kirschner wire 4 can be drilled into the ulna. Since the three groups of through holes 3 are arranged on the curved surface of the bonding plate 1, the guide cylinders 2 are installed on the through holes 3 of different groups, and the tangent angles thereof with the dorsal side of the olecranon 5 process of the ulna are different. In the present embodiment, the closer the guide cylinder 2 is installed to the dorsal distal end of the olecranon, the smaller the angle between the guide cylinder 2 and the dorsal tangent of the olecranon 5 process of the ulna. The angles corresponding to the three groups of through holes 3 are 14°, 17° and 20° respectively. When in use, the medical staff inserts the guide cylinder 2 into different through holes 3 according to the specific situation of the olecranon fracture.

[0038] Embodiment 2: A tension band Kirschner wire guide assembly for olecranon fracture, such as Figures 4-8 As shown, the difference between this embodiment and embodiment 1 is mainly that the angle adjustment mechanism is different. In this embodiment, the angle adjustment mechanism is mainly composed of two parallel fixed plates 12, a driving device and two identical transmission gears 11. The two fixed plates 12 are fixedly mounted on the arc surface of the bonding plate 1, the two transmission gears 11 are located between the two fixed plates 12, and the two transmission gears 11 are meshed with each other. The rotating shaft of the transmission gear 11 is rotatably connected with the fixed plate 12, and the rotating shaft of the transmission gear 11 near the distal end of the dorsal side of the olecranon is fixedly connected with the outer side walls of the two guide cylinders 2. In order to allow the Kirschner wire 4 to drill smoothly into the ulnar olecranon 5 at different angles, two parallel through grooves 6 are opened on the arc surface of the bonding plate 1, and the two guide cylinders 2 are respectively located directly above the two through grooves 6.

[0039] In order to drive the transmission gear 11 to rotate, the driving device of this embodiment is mainly composed of a rack 10, a slider 9 and a limit block 8. Figure 8 As shown, a slide groove 7 is opened on the back side of the bonding plate 1, and three limit grooves 15 are opened at equal intervals on one side of the slide groove 7. The slider 9 is slidably set in the slide groove 7, and the rack 10 is composed of a tooth surface section and a smooth section. The tooth surface section of the rack 10 is meshed with the transmission gear 11, and the smooth section of the rack 10 is located in the bonding plate 1 and is slidably connected thereto. The end of the rack 10 is fixedly connected to the slider 9, so that by moving the slider 9 along the slide groove 7, the transmission gear 11 can be driven to rotate, thereby adjusting the inclination angle of the guide cylinder 2. The limit block 8 is slidably set on the slider 9, combined with Figure 5 As shown, the limit block 8 can slide transversely into the limit groove 15, so that part of the limit block 8 is connected to the slider 9 and the other part is located in the limit groove 15, so that the limit block 8 can fix the entire drive device.

[0040] The limiting grooves 15 are not limited to three either. The more the number, the more fixed angles there are for the guiding cylinder 2. Compared with Embodiment 1, this embodiment can perform stepless adjustment of the angle of the guiding cylinder 2. In addition, the rack 10 of this embodiment is parallel to the tangent line of the dorsal side of the olecranon process, so only the included angle between the Kirschner wire 4 and the rack 10 needs to be measured, and this included angle should be less than 20° as much as possible to avoid the Kirschner wire 4 penetrating the joint cavity.

[0041] To facilitate medical staff to observe the included angle between the guiding cylinder 2 and the tangent line of the dorsal side of the ulnar olecranon 5 process, as shown in combination with Figure 5 and Figure 7 In this embodiment, a protractor 14 is provided on the outer side of the fixing plate 12. A pointer 13 is fixed on the rotating shaft of the transmission gear 11 engaged with the rack 10. The indicating end of the pointer 13 points to the reading of the protractor 14, and the pointer 13 is parallel to the guiding cylinder 2. The 0 scale line of the protractor 14 is parallel to the rack 10, so the angle indicated by the pointer 13 is the angle between the guiding cylinder 2 and the rack 10. Medical staff only need to observe the reading of the pointer 13 to obtain the angle between the Kirschner wire 4 and the tangent line of the dorsal side of the olecranon process.

[0042] Working principle: When the guiding assembly needs to be used, first attach the fitting plate 1 to the dorsal side of the ulnar olecranon 5, and then push up or pull down the slider 9 and the limiting block 8. Since the rack 10 is engaged with the transmission gear 11, when the rack 10 moves at this time, it will drive the transmission gear 11 to rotate. Since both ends of the rotating shaft of the transmission gear 11 are fixedly connected to the two guiding cylinders 2, the angle between the guiding cylinder 2 and the rack 10 can be adjusted in this way. After adjusting the angle of the guiding cylinder 2, the medical staff horizontally move the limiting block 8 so that the limiting block 8 moves into the limiting groove 15, thereby fixing the entire limiting device.

[0043] Embodiment 3: A tension band Kirschner wire guiding assembly for ulnar olecranon fractures. The difference between this embodiment and Embodiment 2 lies in the different sizes of the through groove 6. In this embodiment, the connection line formed by the end of the through groove 6 close to the rack 10 and the rotation center of the guiding cylinder 2 is parallel to the rack 10. The angle between the connection line formed by the other end of the through groove 6 and the rotation center of the guiding cylinder 2 and the rack 10 is 20°. In this way, no matter how the guiding cylinder 2 rotates, as long as the Kirschner wire 4 passes through the guiding cylinder 2 and drills into the ulnar olecranon 5, the angle between the Kirschner wire 4 and the tangent line of the dorsal side of the olecranon is ≤20°, so that the Kirschner wire 4 can be prevented from penetrating the joint cavity.

[0044] Embodiment 4: A tension band Kirschner wire guiding assembly for ulnar olecranon fractures, as shown in Figures 9-10As shown in the figure, the main difference between this embodiment and Embodiment 3 lies in the different structures of the driving devices. The driving device of this embodiment mainly consists of a worm 19, two bevel gears 18 and a first knob 17. The worm 19 meshes with the transmission gear 11, the two bevel gears 18 mesh with each other, and their axles are respectively fixedly connected to the worm 19 and the first knob 17. And the two bevel gears 18 are arranged in the rotation chamber 16 of the fitting plate 1. In this way, only by rotating the first knob 17, the guide cylinder 2 can be driven to rotate through the transmission of the worm and gear 19. By adopting the transmission mode of the worm and gear 19, self-locking can be generated when the guide cylinder 2 rotates to a specified angular position. Compared with Embodiment 3, this structural design is simpler, and its fixation is not limited by the number of the limiting grooves 15, and the stepless adjustment of the angle of the guide cylinder 2 can be completely realized.

[0045] Embodiment 5: A tension band Kirschner wire guiding assembly for olecranon fractures. The main difference between this embodiment and Embodiment 3 and Embodiment 4 lies in the different structures of the driving devices. The driving device of this embodiment is a second knob 20, and the second knob 20 is directly fixedly connected to the axle center of the transmission gear 11 close to the driving device. By rotating the second knob 20, the angle of the guide cylinder 2 can be directly adjusted. Compared with Embodiment 3 and Embodiment 4, the structure of this embodiment is simpler and more convenient for production.

[0046] It should be noted that in this application, no matter how the structure of the angle adjustment mechanism is designed, as long as the angle of the guide cylinder 2 can be adjusted so that the Kirschner wire 4 can be drilled into the olecranon 5 as required, such an angle adjustment mechanism is within the protection scope of this application.

[0047] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A tension band Kirschner wire guiding assembly for olecranon fractures, characterized in that, It includes a fitting plate (1) that can fit on the dorsal side of the olecranon process of the ulna. An angle adjustment mechanism is installed on the arc surface of the fitting plate (1). Two parallel guide cylinders (2) are installed on the angle adjustment mechanism, and the angle adjustment mechanism can adjust the angle between the guide cylinder (2) and the tangent line of the dorsal side of the olecranon process of the ulna.

2. The tension band Kirschner wire guiding assembly for olecranon fracture according to claim 1, characterized in that, The angle adjustment mechanism is three groups of through holes (3) with different angles and penetrating the fitting plate (1). The number of each group of through holes (3) is two; the two guide cylinders (2) are detachably connected to one group of through holes (3).

3. The tension band Kirschner wire guiding assembly for olecranon fractures according to claim 1, characterized in that, The angle adjustment mechanism includes a fixed plate (12), a driving device, and two identical transmission gears (11); the axles of the two transmission gears (11) are rotatably connected to the fixed plate (12), the two transmission gears (11) are meshed with each other, the two ends of the rotating shaft of one transmission gear (11) are respectively fixedly connected to the outer side walls of the two guide cylinders (2), and the other transmission gear (11) is meshed with the driving device; two parallel through slots (6) are opened at the position of the fitting plate (1) where the guide cylinder (2) is located.

4. A tension band Kirschner wire guiding assembly for olecranon fractures according to claim 3, characterized in that, The connection line between the end of the through slot (6) close to the driving device and the rotation axis of the guide cylinder (2) is parallel to the vertical direction of the driving device.

5. A tension band Kirschner wire guiding assembly for olecranon fractures according to claim 3, characterized in that, The driving device includes a rack (10), a slider (9), and a limit block (8); a vertical sliding slot (7) is opened on the dorsal side of the fitting plate (1), and a plurality of limit slots (15) are opened on one side of the sliding slot (7); the rack (10) is meshed with the transmission gear (11), the end of the rack (10) is fixedly connected to the slider (9), the limit block (8) is slidably arranged on the surface of the slider (9), and the limit block (8) can move horizontally into the limit slot (15).

6. The tension band Kirschner wire guiding assembly for olecranon fracture according to claim 3, wherein, The driving device includes a worm (19), two meshing bevel gears (18), and a knob one (17); the worm (19) is meshed with the transmission gear (11), a rotation chamber (16) is opened in the fitting plate (1), the two bevel gears (18) are both located in the rotation chamber (16), and the axles are respectively fixedly connected to the end of the worm (19) and the knob one (17).

7. A tension band Kirschner wire guiding assembly for olecranon fractures according to claim 3, characterized in that, The driving device is a knob two (20), and the rotating shaft of the knob two (20) is fixedly connected to the axle center of the transmission gear (11).

8. A tension band Kirschner wire guiding assembly for olecranon fractures according to any one of claims 5-7, characterized in that An angle measuring device is installed on the fixed plate (12); the angle measuring device includes a protractor (14) and a pointer (13); the protractor (14) is arranged on the fixed plate (12), one end of the pointer (13) is fixedly installed on the axle center of the transmission gear (11) meshed with the driving device, the other end of the pointer (13) points to the scale of the protractor (14), and the pointer (13) is arranged parallel to the guide cylinder (2); the 0 scale line of the protractor (14) is parallel to the driving device.

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