A wedge screw internal fixation device

Abstract

The invention discloses a wedge screw internal fixation device, comprising a lower wedge screw, an upper wedge oblique circular tube and a personalized bone plate. The lower wedge screw comprises an oblique cylindrical small screw segment and an oblique cylindrical large screw segment connected in sequence, the top surface of the oblique cylindrical small screw segment is provided with a cross-shaped groove, the outer wall is provided with an external thread, the oblique cylindrical large screw segment has an inclined surface, and its outer wall is provided with a self-tapping screw thread; a channel is axially provided in the upper wedge oblique circular tube, the oblique cylindrical small screw segment passes through the channel of the elliptical column structure and is sleeved in the upper wedge oblique circular tube from bottom to top, the outer diameter of the oblique cylindrical large screw segment is equal to the outer diameter of the upper wedge oblique circular tube, and the inclined surface of the upper wedge oblique circular tube is equal to the inclined angle of the inclined surface in the oblique cylindrical large screw segment; a screw thread hole is provided on the personalized bone plate, and the screw thread hole has an internal thread matching the oblique cylindrical small screw segment. The structure is designed based on the characteristics of human bones, is easy and efficient to install, has a short operation time during use, can be permanently fixed for osteoporosis patients, and is safe and reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a wedge screw internal fixation device. Background Art

[0002] Bones are divided into cortical bone and cancellous bone. Cortical bone, also called compact bone, maintains the hardness and density of bones and is distributed on the surface of bones. Cancellous bone has a lower bone density than cortical bone, is spongy and elastic, and is distributed inside bones. Osteoporosis is a group of bone diseases caused by various reasons. Bone tissue has normal calcification, and the ratio of calcium salts to matrix is ​​normal. It is a metabolic bone disease characterized by a decrease in the amount of bone tissue per unit volume.

[0003] In the case of osteoporosis, the requirements for bone screws will be higher. The bone screws currently used in clinical practice for osteoporosis still have shortcomings: 1) The size of existing bone screws is limited by the width of the bone plate. If the width of the bone plate is too large, it is not conducive to observing the healing of the fracture. If the screw is too small, the pull-out resistance and shear resistance of the bone screw will be insufficient. Especially in the case of severe osteoporosis, the possibility of failure of the bone screw tightening is greater; 2) There are also bone screws with variable pitch or variable outer diameter in the prior art to fix porous bone, but the operation is difficult. For patients with porous bone, the thinner cortical bone bears the main pull-out resistance and friction of the screw. At this time, once the stress at the cortical bone is too large, it is very likely to cause the threaded connection at the cortical bone to fail. If the pull-out resistance and friction of the screw are borne only by the cancellous bone, the screw will eventually loosen or even break, which will lead to the failure of internal fixation.

[0004] At the same time, fracture is the most common and most serious complication of osteoporosis. Currently, most osteoporotic fracture internal fixation uses cancellous bone screws for fixation. The screw thread is radially screwed into the bone to increase the contact area between the screw thread and the bone. Although the pull-out resistance and friction of the screw are improved to a certain extent, due to the long-term and repeated contact and compression between the screw and the bone, the pull-out resistance of the screw will inevitably be insufficient in the long run, which will eventually lead to failure of internal fixation. Some fixation methods use bicortical bone screws, but this method is very likely to cause secondary damage to the soft tissue on the opposite side of the bone, and the operation requires drilling, tapping, processing the screw channel, and screwing. The cumbersome operation makes the patient more susceptible to infection. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a wedge screw internal fixation device that can be used for internal fixation of osteoporosis and fractures, which can make the diameter of the wedge screw not limited by the width of the personalized bone plate, greatly improve the size design space of the personalized bone plate and the wedge screw, and enable the screw to maintain good pull-out resistance and friction for a long time in the fixation of loose bones. For patients with long-term osteoporosis, the wedge screw internal fixation device can be permanently fixed, safe and reliable.

[0006] A wedge screw internal fixation device according to an embodiment of the present invention comprises:

[0007] The lower wedge screw comprises an oblique cylindrical small screw section and an oblique cylindrical large screw section connected in sequence, a cross-shaped groove is provided on the top surface of the oblique cylindrical small screw section, an external thread is provided on the outer wall of the oblique cylindrical small screw section, the oblique cylindrical large screw section has an inclined surface, and a self-tapping thread is provided on the outer wall of the oblique cylindrical large screw section;

[0008] An upper wedge block oblique circular tube, wherein the upper wedge block oblique circular tube is provided with a channel in the axial direction for the oblique cylindrical small screw segment to pass through, the channel is an elliptical cylinder structure, the oblique cylindrical small screw segment passes through the channel from bottom to top and is sleeved in the upper wedge block oblique circular tube, so that the lower wedge block screw is sleeved with the upper wedge block oblique circular tube, the bottom surface of the upper wedge block oblique circular tube is an inclined surface, and the inclination angle of the bottom surface of the upper wedge block oblique circular tube is equal to the inclined surface of the oblique cylindrical large screw segment;

[0009] A personalized bone plate is provided with a screw hole, wherein the screw hole has an internal thread matching an oblique cylindrical small screw segment.

[0010] The wedge screw internal fixation device according to the embodiment of the present invention has at least the following beneficial effects:

[0011] The elliptical cylinder-shaped channel in the upper wedge block oblique circular tube can be used for the oblique cylindrical small screw section to pass through, and the lower wedge block screw is sleeved with the upper wedge block oblique circular tube, so that the upper wedge block oblique circular tube and the lower wedge block screw can slide on the inclined surface; when fixing, by screwing the cross-shaped groove from bottom to top, the lower wedge block screw can drive the upper wedge block oblique circular tube to rotate in the tightening direction of the screwdriver, thereby driving the lower wedge block screw to move upward, and at the same time, the self-tapping screw teeth in the oblique cylindrical large screw section tap the bone from bottom to top, so that the lower wedge block screw can maintain good pull-out resistance and friction for a long time in the loose bone fixation; wherein, the upper The combination of the wedge oblique circular tube and the lower wedge screw eliminates the need to pass through the personalized bone plate for fixation as in traditional internal fixation. Therefore, the diameter of the lower wedge screw is not limited by the width of the personalized bone plate, greatly improving the size design space of the personalized bone plate and the screw. The diameter of the lower wedge screw is not limited by the width of the personalized bone plate, greatly improving the size design space of the personalized bone plate and the wedge screw. The structure is designed based on the characteristics of human bones, with a simple structure, easy operation, simple and efficient installation and fixation, short operation time, and can be permanently fixed for patients with long-term osteoporosis. It is safe and reliable.

[0012] According to some embodiments of the present invention, the lower wedge screw is integrally formed, which can prevent the connection between the small oblique cylindrical screw section and the large oblique cylindrical screw section from loosening and enhance stability.

[0013] According to some embodiments of the present invention, the outer diameter of the oblique cylindrical large screw segment is equal to the outer diameter of the upper wedge block oblique circular tube.

[0014] According to some embodiments of the present invention, the personalized bone plate is further provided with a boss, the boss is provided with a through hole, the through hole is provided with an internal thread identical to the screw hole, the through hole is coaxial with the screw hole, and the oblique cylindrical small screw segment is passed through together. This ensures that the personalized bone plate has enough screw holes to match the oblique cylindrical small screw segment, and does not affect the overall thickness of the personalized bone plate after fixation, further ensuring the fixed connection between the oblique cylindrical small screw segment and the personalized boss.

[0015] According to some embodiments of the present invention, the through hole is located at the center of the boss, so that the force is evenly distributed, further enhancing the stability of the connection between the personalized bone plate and the lower wedge screw.

[0016] According to some embodiments of the present invention, the personalized bone plate is integrally formed by 3D printing, so that the personalized bone plate can be designed and prepared according to the actual situation of the patient to more accurately match the patient's situation.

[0017] According to some embodiments of the present invention, the wedge screw internal fixation device is made of titanium alloy material.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1 This is a schematic structural diagram of the upper wedge oblique circular tube according to an embodiment of the present invention;

[0021] Figure 2 It is a schematic structural diagram of a lower wedge screw according to an embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of a wedge screw internal fixation device according to an embodiment of the present invention being installed into a bone;

[0023] Upper wedge block oblique round tube 100, channel 110,

[0024] Lower wedge screw 200, oblique cylindrical small screw section 210, cross-shaped groove 211, oblique cylindrical large screw section 220, self-tapping screw thread 221,

[0025] Personalized bone plate 300, boss 310,

[0026] Bone quality: 400. DETAILED DESCRIPTION

[0027] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0028] In the description of the present invention, it should be understood that descriptions involving orientation, such as orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are 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, and therefore should not be understood as a limitation on the present invention.

[0029] In the description of the present invention, unless otherwise clearly defined, words such as provided with, installed, connected, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0030] Reference below Figure 1 , Figure 2 and Figure 3A wedge screw internal fixation device according to an embodiment of the present invention is described.

[0031] like Figure 1-Figure 3 As shown, the wedge screw internal fixation device according to an embodiment of the present invention comprises a lower wedge screw 200, an upper wedge oblique circular tube 100 and a personalized bone plate 300. The lower wedge screw 200 comprises an oblique cylindrical small screw segment 210 and an oblique cylindrical large screw segment 220 connected in sequence, a cross-shaped groove 211 is provided on the top surface of the oblique cylindrical small screw segment 210, an outer wall of the oblique cylindrical small screw segment 210 is provided with an external thread, the oblique cylindrical large screw segment 220 has an inclined surface, and a self-tapping screw thread 221 is provided on the outer wall of the oblique cylindrical large screw segment 220. The combination of the upper wedge oblique circular tube 100 and the lower wedge screw 200 makes it unnecessary to pass through the personalized bone plate 300 for fixation as in traditional internal fixation, thereby making the lower wedge The diameter of the screw 200 is not limited by the width of the personalized bone plate 300, which greatly improves the size design space of the personalized bone plate 300 and the screw. The diameter of the lower wedge screw 200 is not limited by the width of the personalized bone plate 300, which greatly improves the size design space of the personalized bone plate 300 and the wedge screw. The upper wedge oblique circular tube 100 is provided with an elliptical column structure channel 110 along the axial direction for the oblique cylindrical small screw segment 210 to pass through. The oblique cylindrical small screw segment 210 passes through the channel 110 from bottom to top and is sleeved in the upper wedge oblique circular tube 100. , so that the lower wedge screw 200 is sleeved with the upper wedge oblique circular tube 100, the upper wedge oblique circular tube 100 and the lower wedge screw 200 can slide on the inclined surface. During the fixing process, the upper wedge oblique circular tube 100 is immovable, and the lower wedge screw 200 slides upward along the inclined surface; the outer diameter of the oblique cylindrical large screw segment 220 is equal to the outer diameter of the upper wedge oblique circular tube 100, and the bottom surface of the upper wedge oblique circular tube 100 is an inclined surface, and the inclination angle of the inclined surface is equal to that of the inclined surface in the oblique cylindrical large screw segment 220; the personalized bone plate 300 is provided with The screw hole has an internal thread that matches the oblique cylindrical small screw segment 210; when fixing, by screwing the cross-shaped groove 211 from bottom to top, the lower wedge screw 200 can drive the upper wedge oblique circular tube 100 to rotate in the tightening direction of the screwdriver, thereby driving the lower wedge screw 200 to move upward. At the same time, the self-tapping screw thread 221 in the oblique cylindrical large screw segment 220 taps the bone 400 from bottom to top, so that the lower wedge screw 200 can maintain good pull-out resistance and friction for a long time in the fixation of the loose bone 400.

[0032] In some embodiments of the present invention, the lower wedge screw 200 is integrally formed, which can prevent the connection between the oblique cylindrical small screw segment 210 and the oblique cylindrical large screw segment 220 from loosening and enhance stability.

[0033] In some embodiments of the present invention, the outer diameter of the oblique cylindrical large screw segment 220 is equal to the outer diameter of the upper wedge block oblique circular tube 100 .

[0034] In some embodiments of the present invention, a boss 310 is further provided on the personalized bone plate 300, and a through hole is provided on the boss 310. The through hole is provided with an internal thread identical to the screw hole. The through hole is coaxial with the screw hole, and the oblique cylindrical small screw segment 210 is allowed to pass through together. This ensures that the personalized bone plate 300 has sufficient screw holes to cooperate with the oblique cylindrical small screw segment 210, and does not affect the overall thickness of the personalized bone plate 300 after fixation, further ensuring the fixed connection between the oblique cylindrical small screw segment 210 and the personalized boss 310.

[0035] In some embodiments of the present invention, the through hole is located at the center of the boss 310. The force is evenly distributed, further enhancing the stability of the connection between the personalized bone plate 300 and the lower wedge screw 200.

[0036] In some embodiments of the present invention, the personalized bone plate 300 is integrally formed through 3D printing, and combined with the precision advantage of the 3D printed personalized bone plate 300 and the design of the boss 310 in the personalized bone plate 300, the personalized bone plate 300 can be fixed as a compression plate or a locking plate, and the personalized bone plate 300 can be designed and prepared according to the actual situation of the patient to more accurately match the patient's condition.

[0037] In some embodiments of the present invention, the wedge screw internal fixation device is made of titanium alloy material.

[0038] Other structures and operations of the wedge screw internal fixation device according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0039] Reference below Figure 1-Figure 3 , a wedge screw internal fixation device according to an embodiment of the present invention is described in detail with a specific embodiment. It is worth noting that the following description is only an exemplary description and is not a specific limitation of the invention.

[0040] like Figure 1-Figure 3As shown, the wedge screw internal fixation device comprises a lower wedge screw 200, an upper wedge oblique circular tube 100 and a personalized bone plate 300. The lower wedge screw 200 is an oblique cylindrical small screw segment 210 and an oblique cylindrical large screw segment 220 connected in sequence, the top surface of the oblique cylindrical small screw segment 210 is provided with a cross-shaped groove 211, the outer wall of the oblique cylindrical small screw segment 210 is provided with an external thread, the oblique cylindrical large screw segment 220 has an inclined surface, and the outer wall of the oblique cylindrical large screw segment 220 is provided with a self-tapping screw thread 221; an elliptical cylindrical channel 110 is axially provided in the upper wedge oblique circular tube 100, and the oblique cylindrical small screw segment 210 passes through the channel 110 from bottom to top and is sleeved in the upper wedge oblique circular tube 100; the oblique cylindrical large screw The outer diameter of the segment 220 is equal to the outer diameter of the upper wedge oblique circular tube 100, and the bottom surface of the upper wedge oblique circular tube 100 is an inclined surface, and the inclination angle of the inclined surface is equal to the inclined surface in the oblique cylindrical large screw segment 220; a screw hole is provided on the personalized bone plate 300, and the screw hole has an internal thread matching the oblique cylindrical small screw segment 210; the upper wedge oblique circular tube 100 and the lower wedge screw 200 are combined through the oblique cylindrical small screw segment 210, and then the oblique cylindrical small screw segment 210 is placed under the personalized bone plate 300 and aligned with the screw hole in the personalized bone plate 300.

[0041] Specifically, when the wedge screw internal fixation device is applied to the internal fixation surgery of osteoporosis patients, the designed hole position is first drilled with a drill, and the diameter of the nail channel is required to be equal to the outer diameter of the upper wedge oblique circular tube 100, and the depth of the nail channel is equal to the height of the upper wedge oblique circular tube 100 plus the height of the boss 310 in the personalized bone plate 300. In this way, it is ensured that there are enough screw holes to match the oblique cylindrical small screw segment 210, and the overall thickness of the personalized bone plate 300 is not affected after fixation, thereby further ensuring the fixed connection between the oblique cylindrical small screw segment 210 and the personalized boss 310; then the upper wedge oblique circular tube 100 and the lower wedge screw 200 are combined through the oblique cylindrical small screw segment 210, and the oblique cylindrical small screw segment 210 in the lower wedge screw 200 is placed into the nail channel in an upward direction, and the oblique cylindrical small screw segment 210 of the lower wedge screw 200 is aligned with the personalized bone plate 30 0 and the screw thread hole above the boss 310, use a cross screwdriver to screw the lower wedge screw 200 into the through hole in the center of the boss 310 of the personalized bone plate 300, at this time, press the personalized bone plate 300 to move downward, while the lower wedge screw 200 drives the upper wedge oblique circular tube 100 to rotate in the direction of tightening the screwdriver, and the personalized bone plate 300 and the upper wedge oblique circular tube 100 are fitted and then continue to be tightened. At this time, the lower wedge screw 200 drives the upper wedge oblique circular tube 100 to continue to rotate and the lower wedge screw 200 begins to move upward and enters the screw thread hole in the personalized bone plate 300. At the same time, the self-tapping screw thread 221 on the oblique cylindrical large screw segment 220 begins to tap the bone 400 from bottom to top until the lower wedge screw 200 slides in the channel 110 of the upper wedge oblique circular tube 100 to the limit position of the stroke, that is, the fixation of the loose bone 400 is completed. In this way, the diameter of the lower wedge screw 200 is not limited by the width of the personalized bone plate 300, which greatly improves the size design space of the personalized bone plate 300 and the wedge screw, and enables the screw to maintain good pull-out resistance and friction for a long time in the fixation of loose bone 400, especially for patients with long-term loose bone 400, and can ensure the reliability of internal fixation.

[0042] In the description of this specification, the description with reference to the terms "some embodiments" or "examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0043] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A wedge screw internal fixation device, characterized in that: include: The lower wedge screw comprises an oblique cylindrical small screw section and an oblique cylindrical large screw section connected in sequence, a cross-shaped groove is provided on the top surface of the oblique cylindrical small screw section, an external thread is provided on the outer wall of the oblique cylindrical small screw section, the oblique cylindrical large screw section has an inclined surface, and a self-tapping thread is provided on the outer wall of the oblique cylindrical large screw section, and the lower wedge screw is integrally formed; An upper wedge block oblique circular tube, wherein the upper wedge block oblique circular tube is provided with a channel in the axial direction for the oblique cylindrical small screw segment to pass through, the channel is an elliptical cylinder structure, the oblique cylindrical small screw segment passes through the channel from bottom to top and is sleeved in the upper wedge block oblique circular tube, so that the lower wedge block screw is sleeved with the upper wedge block oblique circular tube, the bottom surface of the upper wedge block oblique circular tube is an inclined surface, the bottom surface of the upper wedge block oblique circular tube is equal to the inclined surface of the oblique cylindrical large screw segment at an inclination angle, and the outer diameter of the oblique cylindrical large screw segment is equal to the outer diameter of the upper wedge block oblique circular tube; A personalized bone plate is provided with a screw hole, wherein the screw hole has an internal thread matching an oblique cylindrical small screw segment.

2. The wedge screw internal fixation device according to claim 1, characterized in that: The personalized bone plate is also provided with a boss, the boss is provided with a through hole, the through hole is provided with an internal thread identical to the screw hole, the through hole is coaxial with the screw hole, and an oblique cylindrical small screw segment passes through.

3. The wedge screw internal fixation device according to claim 2, characterized in that: The through hole is located at the center of the boss.

4. The wedge screw internal fixation device according to claim 1, characterized in that: The personalized bone plate is integrally formed through 3D printing.

5. The wedge screw internal fixation device according to claim 1, characterized in that: The wedge screw internal fixation device is made of titanium alloy material.

Images