A sleeve combined tension-compression internal fixation screw

Abstract

The present invention provides a sleeve combination tension-compression internal fixation screw, belonging to the technical field of medical devices. It includes an outer screw sleeve, and an inner core fixing screw is slidably connected to the inner cavity of the outer screw sleeve. A curved sleeve plate is fixedly connected to the middle of the inner cavity of the outer screw sleeve; a limit locking assembly, which is used to shorten the distance between the outer screw sleeve and both ends of the fracture, and the limit locking assembly is connected to the outer screw sleeve. Through the limit locking assembly of the present invention, the sliding of the inner core fixing screw is facilitated, and the resistance of the inner core fixing screw to slide is reduced. In such a state, the inner core fixing screw is in the most stable state, and different distances can be selected according to the severity of the fracture end, so as to change different compression effects, greatly improving the holding force of the inner core fixing screw at the fracture end, thereby ensuring that the inner core fixing screw can play a role in compressing the fracture end.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly relates to a sleeve combined tension compression internal fixation screw. Background Art

[0002] In modern orthopedic medicine, screws have almost become essential implants for each operation. Traditional screws are divided into full screws and half screws. After the two ends of the fracture are fixed by the screws and pass through the double cortical bone, the screws play a fixing role on the fracture ends. At the same time, the rotation between the tail screw and the tip can reduce the distance between the fracture ends, thereby generating a pressure effect on the fracture ends, that is, the compression effect.

[0003] However, in actual use, for patients with bone loss or bone transport, the bone density is lower than that of normal people. In daily life, the bone cortex will become thinner and the bone density will also become sparse, that is, the physical strength of the bone is reduced. When using internal fixation screws to fix fractures, the tip position of ordinary screws is fixed in the fracture area. However, due to the low bone density of the patient himself, the contact area between the screw tip and the bone quality will become loose, and the bone's wrapping of the screw will be reduced. It is easy for the screw to become loose during the fixation process, and even when the patient moves, the screw will be displaced along with the swing of the bone, greatly reducing the holding force of the screw on the fracture ends, thereby causing the ordinary screw to fail to exert a compression effect on the fracture ends.

[0004] Therefore, the present invention provides a sleeve combined tension compression internal fixation screw to meet the needs. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a sleeve combined tension compression internal fixation screw to solve the problem that the tip position of the existing ordinary screw is fixed in the fracture area, and due to the low bone density of the patient himself, the contact area between the screw tip and the bone quality will become loose, and the bone's wrapping of the screw will be reduced. It is easy for the screw to become loose during the fixation process, and even when the patient moves, the screw will be displaced along with the swing of the bone, greatly reducing the holding force of the screw on the fracture ends, thereby causing the ordinary screw to fail to exert a compression effect on the fracture ends.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] A sleeve combined tension compression internal fixation screw, comprising an outer screw sleeve, an inner core fixing screw slidably connected to the inner cavity of the outer screw sleeve, a telescopic rod fixedly connected to the middle of the top of the inner core fixing screw, and an arc-shaped sleeve plate fixedly connected to the middle of the inner cavity of the outer screw sleeve; a limit locking assembly for shortening the distance between the outer screw sleeve and the two ends of the fracture, and the limit locking assembly is connected to the outer screw sleeve.

[0008] Optionally, the limit lock includes a first limit portion opened at the bent end of the arc-shaped sleeve plate. A second limit portion is opened at the lower bent end of the arc-shaped sleeve plate. A correction block is fixedly connected to the inner cavity of the outer screw sleeve near the end of the arc-shaped sleeve plate.

[0009] Optionally, an adapter block is fixedly connected to the inner cavity of the outer screw sleeve near the correction block. A clamping groove is opened at the upper bent end of the adapter block. A U-shaped limit block is fixedly connected to the inner cavity of the outer screw sleeve near the adapter block.

[0010] Optionally, a U-shaped clamping plate is clamped on the outer surface of the top of the inner core fixing screw. A protection plate is fixedly connected to the side surface of the upper bent end of the U-shaped clamping plate. A buffer arc pad is fixedly connected to the bottom of the protection plate.

[0011] Optionally, an elastic sheet is fixedly connected to the inner cavity of the lower bent end of the U-shaped clamping plate. A weakening portion is opened at the lower bent end of the U-shaped clamping plate near the elastic sheet. A hollow frame is fixedly connected to the top end of the inner core fixing screw.

[0012] Optionally, an active rubber plug is fixedly connected to the inner surface of the telescopic rod near the top end of the outer screw sleeve. A blocking piece is fixedly connected to the middle of the bottom end of the active rubber plug.

[0013] Optionally, the arc-shaped sleeve plate is made of plastic and the inner cavity is hollow. The first limit portion and the second limit portion are symmetrically distributed horizontally through the middle of the arc-shaped sleeve plate. One end of the correction block away from the inner wall of the outer screw sleeve is arc-shaped, and a transverse groove is opened in the middle of the arc.

[0014] Optionally, the length of the opened clamping groove is half of that of the adapter block. The U-shaped limit block is made of plastic, and the upper and lower bent ends are provided with hooks.

[0015] Optionally, the opposite surface of the U-shaped clamping plate clamped with the inner core fixing screw is fixedly connected to the inner cavity of the outer screw sleeve. The upper and lower bent ends of the U-shaped clamping plate are provided with hollow shapes. The contact end of the buffer arc pad and the protection plate is flat, the opposite surface is an outwardly convex arc, and the inside is hollow.

[0016] Optionally, the elastic sheet is fixedly connected to the inner cavity of the lower bent end of the U-shaped clamping plate. The middle of the hollow frame is hollow, and the shape of the hollow frame is adapted to the outer surface shape of the top of the inner core fixing screw.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] In the above solution, through the limit locking component, it is convenient for the inner core fixing screw to slide, reducing the resistance of the inner core fixing screw to slide. In such a state, the inner core fixing screw is in the most stable state and can select different distances according to the severity of the fracture end, thereby changing different pressurizing effects, greatly improving the holding force of the inner core fixing screw at the fracture end, and ensuring that the inner core fixing screw can play a pressurizing role on the fracture end.

[0019] By setting the telescopic rod, the active rubber plug and the baffle, in the normal state, the active rubber plug has stability and can withstand a certain pressure, so as to ensure that when the telescopic rod shakes slightly, the active rubber plug can give a limit. When fixing the fracture end, it is necessary to continuously reduce the distance to generate a pressurizing effect.

[0020] By setting the U-shaped clamping plate, the buffer arc pad, the elastic sheet and the weakening part, the inner core fixing screw will no longer slide upward when it is clamped here, that is, the shortest distance between the outer screw sleeve and the inner core fixing screw, so as to effectively adjust the distance. It is convenient and can also minimize the damage to the patient to the greatest extent, improving the practicability and convenience of the device.

[0021] By setting the telescopic rod and the arc-shaped sleeve plate, when the arc-shaped sleeve plate contacts the periphery of the top of the inner core fixing screw, it will just clamp the periphery of the top of the inner core fixing screw in the inner cavity of the arc-shaped sleeve plate. The upper and lower bending ends of the arc-shaped sleeve plate can well prevent the inner core fixing screw from encountering large obstacles during the up and down sliding, thereby reducing the additional damage of the inner core fixing screw to the patient's fracture site. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings incorporated herein and constituting a part of the specification illustrate embodiments of the present invention and, together with the specification, are further used to explain the principles of the present invention and enable those skilled in the relevant art to implement and use the present invention.

[0023] Figure 1 It is a three-dimensional structural schematic diagram of a sleeve combination type tension compression internal fixing screw;

[0024] Figure 2 It is a sectional three-dimensional structural schematic diagram of a sleeve combination type tension compression internal fixing screw;

[0025] Figure 3 For Figure 2 The partial enlarged structural schematic diagram at position A in

[0026] Figure 4 For Figure 2 The partial enlarged structural schematic diagram at position B in

[0027] Figure 5 It is a three-dimensional enlarged structural schematic diagram of the arc-shaped sleeve plate, the first limiting part and the second limiting part;

[0028] Figure 6 Schematic diagram of the three-dimensional enlarged structure of the correction block, adaptation block and U-shaped limit block;

[0029] Figure 7 Schematic diagram of the three-dimensional enlarged structure of the U-shaped clamping plate, protection plate and buffer arc pad;

[0030] Figure 8 is Figure 7 Schematic diagram of the partial enlarged structure at position C in

[0031] Figure 9 is Figure 8 Schematic diagram of the partial enlarged structure at position D in

[0032] Figure 10 Schematic diagram of the three-dimensional enlarged structure of the U-shaped clamping plate, elastic sheet and weakening part I;

[0033] Figure 11 Schematic diagram of the three-dimensional enlarged structure of the inner core fixing screw and the telescopic rod.

[0034] Reference numerals:

[0035] 1. Outer screw sleeve; 2. Inner core fixing screw; 201. U-shaped clamping plate; 202. Protection plate; 203. Buffer arc pad; 204. Elastic sheet; 205. Weakening part; 206. Hollow frame; 3. Telescopic rod; 301. Active rubber plug; 302. Retaining piece; 4. Arc-shaped sleeve plate; 401. Limit part I; 402. Limit part II; 403. Correction block; 404. Adaptation block; 405. Clamping groove; 406. U-shaped limit block.

[0036] As shown in the figure, in order to clearly implement the structure of the embodiments of the present invention, specific structures and devices are marked in the figure, but this is only for schematic needs and is not intended to limit the present invention to this specific structure, device and environment. According to specific needs, those of ordinary skill in the art can adjust or modify these devices and environments. Detailed implementation manners

[0037] The following describes in detail a sleeve combined tension and compression internal fixing screw provided by the present invention with reference to the accompanying drawings and specific embodiments. At the same time, it should be noted here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments. For some well-known technologies, those skilled in the art can also adopt other alternative methods for implementation; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0038] It should be noted that in the specification, references to "one embodiment", "an embodiment", "exemplary embodiments", "some embodiments", etc. indicate that the described embodiments may include a particular feature, structure, or characteristic, but not necessarily every embodiment includes that particular feature, structure, or characteristic. Additionally, when describing a particular feature, structure, or characteristic in connection with an embodiment, implementing such feature, structure, or characteristic in connection with other embodiments (whether or not explicitly described) should be within the knowledge of those skilled in the relevant art.

[0039] Generally, terms can be understood, at least in part, from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or can be used to describe a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood to not necessarily be intended to convey a set of exclusive factors, but rather, alternatively, depending at least in part on the context, to allow for the existence of other factors that may not necessarily be explicitly described.

[0040] It can be understood that the meanings of "on", "above", and "over" in the present invention should be interpreted in the broadest manner such that "on" not only means "directly on" something, but also includes the meaning of being "on" something with intervening features or layers therebetween, and "above" or "over" not only means "above" or "over" something, but also can include the meaning of being "above" or "over" something with no intervening features or layers therebetween.

[0041] Furthermore, spatial relative terms such as "under", "below", "lower", "above", "upper", etc. may be used herein for convenience of description to describe the relationship of one element or feature to another or other elements or features, as illustrated in the figures. Spatial relative terms are intended to cover different orientations in the use or operation of the device in addition to the orientation depicted in the figures. The device may be otherwise oriented, and the spatial relative descriptors used herein may be interpreted accordingly.

[0042] Such as Figures 1 to 11As shown in the figure, an embodiment of the present invention provides a sleeve combined tension-compression internal fixation screw, which includes an outer screw sleeve 1. A core fixing screw 2 is slidably connected to the inner cavity of the outer screw sleeve 1. A telescopic rod 3 is fixedly connected to the middle of the top of the core fixing screw 2. An arc-shaped sleeve plate 4 is fixedly connected to the middle of the inner cavity of the outer screw sleeve 1; a limit locking component, which is used to shorten the distance between the outer screw sleeve 1 and both ends of the fracture. The limit locking component is connected to the outer screw sleeve 1. In the present invention, the overall material of the outer screw sleeve 1 is titanium alloy, and its interior is hollow. The diameter of the top of the outer screw sleeve 1 is larger than that of the middle, and there are notches in a circular array at the top to facilitate screwing. The core fixing screw 2 is cylindrical as a whole. The part extending into the outer screw sleeve 1 is a flat end, and the exposed part is a tip, which is convenient for piercing into the fracture area of the patient. The outer surface of the core fixing screw 2 is slidably connected to the inner cavity of the outer screw sleeve 1. The diameter of the core fixing screw 2 is slightly smaller than the inner diameter of the outer screw sleeve 1. A slot is opened in the middle of the top of the core fixing screw 2. The diameter of the telescopic rod 3 is adapted to the diameter of the slot in the top of the core fixing screw 2. The telescopic rod 3 is a prior art, which is divided into an outer sleeve and an inner core tube. The outer sleeve is clamped at the top position of the outer screw sleeve 1, and the inner core tube is connected to the core fixing screw 2 for lifting and lowering movement. The bottom end of the telescopic rod 3 is fixed in the slot of the top of the core fixing screw 2.

[0043] Among them, during the use process, first, the top with a large diameter of the outer screw sleeve 1 is abutted against one end of the fracture area. The notches on its large diameter can increase the friction with the fracture area, thereby enhancing the holding force on the bone mass. In the initial state, the tip of the core fixing screw 2 extends out of most of the bottom end of the outer screw sleeve 1, and a small part of the top of the core fixing screw 2 is located in the inner cavity of the outer screw sleeve 1, which is convenient for directly abutting against the corresponding position of the fracture area at the beginning of the work to improve accuracy. Then, the bone mass at the fracture area of the broken end is gradually approached. The main way of approaching is to rely on the sliding connection of the core fixing screw 2 in the inner cavity of the outer screw sleeve 1. The telescopic rod 3 is fixed in the slot of the top of the core fixing screw 2, which can further ensure that the sliding track of the core fixing screw 2 in the inner cavity of the outer screw sleeve 1 is vertical to avoid deviation. During the sliding process, through the arc-shaped sleeve plate 4, when the arc-shaped sleeve plate 4 contacts the periphery of the top of the core fixing screw 2, it will just clamp the periphery of the top of the core fixing screw 2 in the inner cavity of the arc-shaped sleeve plate 4. The upper and lower curved ends of the arc-shaped sleeve plate 4 can well prevent the core fixing screw 2 from having a large obstacle during the up and down sliding, thereby reducing the additional damage of the core fixing screw 2 to the patient's fracture site.

[0044] As Figure 3As shown, a reactive rubber plug 301 is fixedly connected to the inner surface of the telescopic rod 3 near the top end of the outer screw sleeve 1. A retaining piece 302 is fixedly connected to the middle of the bottom end of the reactive rubber plug 301. The reactive rubber plug 301 is made of rubber and has vertically arrayed grooves at its end. The outer surface of the reactive rubber plug 301 slides in the inner cavity of the outer screw sleeve 1. A notch is formed in the middle of the reactive rubber plug 301, and the diameter size of the notch is adapted to the diameter size of the telescopic rod 3. The retaining piece 302 is made of a rigid material, and the middle of the retaining piece 302 is fixed at the middle position of the telescopic rod 3 near the bottom end of the reactive rubber plug 301 and moves along with the movement of the upper half of the telescopic rod 3.

[0045] In the present invention, if the outer surface of the reactive rubber plug 301 is not provided with grooves, it will be very difficult for the reactive rubber plug 301 to slide in the inner cavity of the outer screw sleeve 1, similar to pulling the push rod in the inner cavity of a syringe after blocking the needle of the syringe. By providing grooves, the sealing performance between the reactive rubber plug 301 and the outer screw sleeve 1 can be weakened, thereby improving the sliding effect of the reactive rubber plug 301. Since the titanium alloy material itself has good magnetic compliance performance, but is relatively prone to fatigue and fracture. If the patient is a growing teenager or in a situation where it needs to be removed after recovery, we often pull the top position of the telescopic rod 3 and then pull it outwards. During the pulling process, the telescopic rod 3 will gradually be pulled out. The retaining piece 302 is fixed on the surface of the telescopic rod 3, so the retaining piece 302 will move synchronously with the pulling of the telescopic rod 3. When it moves to the reactive rubber plug 301, it will abut against the bottom of the reactive rubber plug 301. In the normal state, the reactive rubber plug 301 has stability and can withstand a certain pressure, so as to ensure that when the telescopic rod 3 shakes slightly, the reactive rubber plug 301 can provide a limit. When fixing the fracture end, it is necessary to continuously reduce the distance to generate a pressing effect.

[0046] Such as Figures 4 to 6As shown, the limit lock includes a first limit portion 401 opened at the bent end of the arc-shaped sleeve plate 4. A second limit portion 402 is opened at the lower bent end of the arc-shaped sleeve plate 4. A correction block 403 is fixedly connected to the inner cavity of the outer screw sleeve 1 near the end of the arc-shaped sleeve plate 4. An adapter block 404 is fixedly connected to the inner cavity of the outer screw sleeve 1 near the correction block 403. A clamping groove 405 is opened at the upper bent end of the adapter block 404. A U-shaped limit block 406 is fixedly connected to the inner cavity of the outer screw sleeve 1 near the adapter block 404. The first limit portion 401 and the second limit portion 402 are respectively opened in the inner cavity of the arc-shaped sleeve plate 4 and are symmetrically distributed horizontally. The arc-shaped sleeve plate 4 is made of plastic as a whole and is hollow inside. The arc-shaped sleeve plate 4 is distributed on the inner cavity of the outer screw sleeve 1 according to the size of the inner diameter of the outer screw sleeve 1. Since the material of the inner core fixing screw 2 is titanium alloy and not very heavy, the two ends of the arc-shaped sleeve plate 4 are cut open so that the arc-shaped sleeve plate 4 is not a connected whole. The flat end of the correction block 403 is fixed in the inner cavity of the outer screw sleeve 1 and near the end of the arc-shaped sleeve plate 4, while the arc end of the correction block 403 is open, and a transverse groove is opened in the middle of the arc end. The flat end of the adapter block 404 is fixed in the inner cavity of the outer screw sleeve 1 and is located at the lower end of the correction block 403, while the arc end is open. In order to enhance the clamping and locking effect of the inner core fixing screw 2, a clamping groove 405 is opened on the inner wall of the upper arc surface of the adapter block 404, and the opening length of the clamping groove 405 is half of the whole clamping groove 405. The flat end of the U-shaped limit block 406 is fixed at the lower end of the adapter block 404 in the inner cavity of the outer screw sleeve 1. The U-shaped limit block 406 presents a U shape, and the end far from the inner wall of the outer screw sleeve 1 is a bent end.

[0047] In the above-mentioned present invention, each component is made of plastic material, and a number of components are distributed in a vertical array with the same number. When in use, the distance between the outer screw sleeve 1 and the inner core fixing screw 2 is continuously shortened. Under the action of the thrust, the inner core fixing screw 2 begins to slide in the inner cavity of the outer screw sleeve 1, and the flat end of the inner core fixing screw 2 begins to contact the U-shaped limit block 406 first. When the curved end of the U-shaped limit block 406 contacts the flat end of the inner core fixing screw 2, the applied thrust will cause the lower curved end of the U-shaped limit block 406 to deform first. If the supporting capacity of the deformation is less than the thrust, the inner core fixing screw 2 will be deformed. The fixing screw 2 continues to slide. At this time, when the bottom of the flat end of the inner core fixing screw 2 is completely stuck in the lower curved end of the U-shaped limit block 406, the inner core fixing screw 2 is in a preliminary clamping and fixing state. Since the inner core fixing screw 2 is only clamped and fixed by the U-shaped limit block 406 at this time, it has a certain instability. If it continues to be pushed upward, the thrust will be greater than the supporting capacity of the upper curved end of the U-shaped limit block 406, which will cause the flat end of the inner core fixing screw 2 to break away from the clamping area of the U-shaped limit block 406, so that the flat end of the inner core fixing screw 2 comes to the adapter block 404, and the adapter block 404 is in the middle of the arc sleeve plate 4. The same level, that is, when the inner core fixing screw 2 is clamped in the adapter block 404, it is most stable. At this time, the clamping groove 405 will clamp the moving inner core fixing screw 2. At the same time as the clamping groove 405 is clamped, other positions of the plane end of the inner core fixing screw 2 are also in contact with the arc sleeve 4, and the limiting part 402 will preferentially resist the plane end of the inner core fixing screw 2 and concave toward the hollow position of the arc sleeve 4 during deformation, which facilitates the sliding of the inner core fixing screw 2 and reduces the sliding resistance of the inner core fixing screw 2. When the plane end of the inner core fixing screw 2 is completely in the middle position of the arc sleeve 4, the limiting part 402 It will abut against the bottom of the flat end of the inner core fixing screw 2, the limiting portion 401 will abut against the top of the flat end of the inner core fixing screw 2, and the clamping groove 405 will clamp against the top of the flat end of the inner core fixing screw 2. In this state, the inner core fixing screw 2 is in the most stable state. In the case of non-violent exercise, the relative position of the fracture ends can be well maintained, and different distances can be selected according to the severity of the fracture ends, thereby changing different pressurization effects, which greatly improves the holding force of the inner core fixing screw 2 at the fracture ends, thereby ensuring that the inner core fixing screw 2 can exert a pressurizing effect on the fracture ends.

[0048] like Figures 7 to 11As shown, a U-shaped clamping plate 201 is clamped on the outer surface of the top of the inner core fixing screw 2. A protection plate 202 is fixedly connected to the side surface of the bent end of the U-shaped clamping plate 201. A buffer arc pad 203 is fixedly connected to the bottom of the protection plate 202. An elastic piece 204 is fixedly connected to the inner cavity of the lower bent end of the U-shaped clamping plate 201. A weakening part 205 is provided at the lower bent end of the U-shaped clamping plate 201 close to the elastic piece 204. The top end of the inner core fixing screw 2 is fixedly connected with a hollowed-out frame 206. The U-shaped clamping plate 201 is made of plastic. The flat end of the U-shaped clamping plate 201 is fixed in the middle of the inner cavity of the inner core fixing screw 2, above the arc-shaped sleeve plate 4 at the top of the vertical array. The open end of the U-shaped clamping plate 201 is divided into an upper end and a lower end. The lower end is provided with a hollow, and the lower end has an extended part. The protection plate 202 is a solid disc, and the diameter edge is fixed to the inner wall of the upper end of the U-shaped clamping plate 201. The buffer arc pad 203 is in the shape of flat on the top and convex on the bottom, with a hollow inside. The flat end is fixed to the bottom of the protection plate 202, and the protruding end faces downward, which is convenient for directly contacting the top end of the inner core fixing screw 2, can play a certain buffering effect, and at the same time can prevent the inner core fixing screw 2 from being blocked and the counter impact force from causing secondary damage to the fracture site. The elastic piece 204 is made of wavy plastic and is fixed in the middle of the hollow of the lower end of the U-shaped clamping plate 201. The weakening part 205 is opened at the extended part of the lower end of the U-shaped clamping plate 201, and is concentrated at the intersection of the U-shaped clamping plate 201 and the extended part. The hollowed-out frame 206 is a hollowed-out frame, and its shape is adapted to the edge shape of the flat end of the inner core fixing screw 2. The side surface of the hollowed-out frame 206 is fixed to the edge of the flat end of the inner core fixing screw 2.

[0049] In the present invention, the U-shaped clamping plate 201 is fixed in the inner cavity of the outer screw sleeve 1. In the initial state, the overall length of the inner core fixing screw 2 is less than the length of the outer screw sleeve 1. Therefore, when the inner core fixing screw 2 completely enters the interior of the outer screw sleeve 1, there will still be a part of the hollow space at the top of the outer screw sleeve 1. In order to prevent the tip of the inner core fixing screw 2 from coming into contact with the fracture end, the distance between the U-shaped clamping plate 201 and the bottom end of the outer screw sleeve 1 is less than the length of the inner core fixing screw 2. Thus, when the top of the inner core fixing screw 2 is completely clamped inside the U-shaped clamping plate 201, there is still a tip part exposed outside. Similarly, the inner core fixing screw 2 will slide in the inner cavity of the outer screw sleeve 1 and gradually approach the position of the U-shaped clamping plate 201. It will first come into contact with the extending part of the U-shaped clamping plate 201. Under the action of the thrust, the extending part will cooperate with the weakening part 205 to turn upwards. When the extending part turns, it will also be pressed against the hollow frame 206. The inside of the hollow frame 206 is hollow, so it will also be pressed against the edge of the flat end of the inner core fixing screw 2. When the extending part gradually turns to the vertical position, the hollow frame 206 will slide into the inside of the U-shaped clamping plate 201. At this time, the hollow frame 206 is no longer pressed and returns to its original state. The inner core fixing screw 2 continues to slide. When the top of the inner core fixing screw 2 touches the protruding end of the buffer arc pad 203, under the action of the thrust, the protruding end will deform and press upwards. During the pressing process, the bottom of the flat end of the inner core fixing screw 2 will abut against the extending part of the U-shaped clamping plate 201 that has returned to its original state. The extending part will support a part of the bottom of the flat end of the inner core fixing screw 2, and most of the bottom of the flat end of the inner core fixing screw 2 will be supported by the lower end of the U-shaped clamping plate 201, and the key position is directly above the elastic piece 204. Through the deformation of the elastic piece 204, it can be ensured to the greatest extent that the thrust during the clamping of the inner core fixing screw 2 is weakened, thereby reducing the damage to the patient's fracture end caused by the counter impact. In this way, the inner core fixing screw 2 will no longer slide upwards, which is the shortest distance between the outer screw sleeve 1 and the inner core fixing screw 2, thus effectively adjusting the distance, being convenient and at the same time reducing the damage to the patient to the greatest extent, improving the practicability and convenience of the device.

[0050] The working process of the technical solution of the present invention is as follows:

[0051] In the initial state, the positions of the outer screw sleeve 1 and the inner core fixing screw 2 are the shortest, that is, only part of the tip position of the inner core fixing screw 2 is exposed outside (as Figure 11 ), and by pushing the position at the top of the telescopic rod 3, the inner core fixing screw 2 gradually slides out (as Figure 2 ).

[0052] During use, first place the top of the outer screw sleeve 1 with a large diameter against one end of the fracture area. The notch on its large diameter can increase the friction with the fracture area, thereby enhancing the holding force on the bone mass. In the initial state, the tip of the inner core fixing screw 2 extends out of most of the bottom end of the outer screw sleeve 1, and a small part of the top end of the inner core fixing screw 2 is located in the inner cavity of the outer screw sleeve 1, which is convenient for directly abutting against the corresponding position of the fracture area at the beginning of work to improve accuracy. Then, gradually bring the bone ends of the fracture area closer. The main way of approaching is completed by the sliding connection of the inner core fixing screw 2 in the inner cavity of the outer screw sleeve 1. The telescopic rod 3 is fixed in the slot hole at the top end of the inner core fixing screw 2, which can ensure that the sliding track of the inner core fixing screw 2 in the inner cavity of the outer screw sleeve 1 is vertical to avoid deviation. During the sliding process, through the arc-shaped sleeve plate 4, when the arc-shaped sleeve plate 4 contacts the periphery of the top of the inner core fixing screw 2, it will just clamp the periphery of the top of the inner core fixing screw 2 in the inner cavity of the arc-shaped sleeve plate 4. The upper and lower curved ends of the arc-shaped sleeve plate 4 can well prevent the inner core fixing screw 2 from being greatly hindered during the up and down sliding, thereby reducing the additional damage of the inner core fixing screw 2 to the patient's fracture site.

[0053] When in use, the distance between the outer screw sleeve 1 and the inner core fixing screw 2 is continuously shortened. Under the action of the thrust, the inner core fixing screw 2 begins to slide in the inner cavity of the outer screw sleeve 1, and the flat end of the inner core fixing screw 2 begins to contact the U-shaped limit block 406 first. When the curved end of the U-shaped limit block 406 hits the flat end of the inner core fixing screw 2, the applied thrust will cause the lower curved end of the U-shaped limit block 406 to deform first. If the supporting capacity of the deformation is less than the thrust, the inner core fixing screw 2 will continue to slide. At this time, when the inner core fixing screw 2 After the bottom of the flat end is completely stuck in the lower curved end of the U-shaped limit block 406, the inner core fixing screw 2 is in a preliminary clamping and fixing state. Since the inner core fixing screw 2 is only clamped and fixed by the U-shaped limit block 406 at this time, it has a certain instability. If it continues to be pushed upward, the thrust will be greater than the supporting capacity of the upper curved end of the U-shaped limit block 406, which will cause the flat end of the inner core fixing screw 2 to break away from the clamping area of the U-shaped limit block 406, so that the flat end of the inner core fixing screw 2 comes to the adapter block 404, and the adapter block 404 is at the same level as the middle part of the arc sleeve plate 4. That is, when the inner core fixing screw 2 is clamped in the adapter block 404, it is most stable. At this time, the clamping groove 405 will clamp the moving inner core fixing screw 2. At the same time as the clamping groove 405 is clamped, other positions of the plane end of the inner core fixing screw 2 are also in contact with the arc sleeve 4. The limiting part 402 will preferentially resist the plane end of the inner core fixing screw 2 and concave toward the hollow position of the arc sleeve 4 during deformation. This effect facilitates the sliding of the inner core fixing screw 2 and reduces the sliding resistance of the inner core fixing screw 2. When the plane end of the inner core fixing screw 2 is completely in the middle position of the arc sleeve 4 When in the position, the limiting part 402 will abut against the bottom of the plane end of the inner core fixing screw 2, the limiting part 401 will abut against the top of the plane end of the inner core fixing screw 2, and the clamping groove 405 will clamp on the top of the plane end of the inner core fixing screw 2. In this state, the inner core fixing screw 2 is in the most stable state, which is the purpose of locking the inner core fixing screw 2. In the case of non-violent exercise, the relative position of the fracture ends can be well maintained, ensuring the holding force of the inner core fixing screw 2 at the fracture ends, thereby improving the pressurization effect of the inner core fixing screw 2 on the fracture ends.

[0054] The U-shaped clamping plate 201 is fixed in the inner cavity of the outer screw sleeve 1. In the initial state, the overall length of the inner core fixing screw 2 is less than the length of the outer screw sleeve 1. So when the inner core fixing screw 2 completely enters the inside of the outer screw sleeve 1, there will still be a part of the hollow space at the top of the outer screw sleeve 1. In order to prevent the tip of the inner core fixing screw 2 from contacting the fracture end, the distance between the U-shaped clamping plate 201 and the bottom end of the outer screw sleeve 1 is less than the length of the inner core fixing screw 2. Thus, when the top of the inner core fixing screw 2 is completely clamped inside the U-shaped clamping plate 201, there is still a tip part exposed outside. Similarly, the inner core fixing screw 2 will slide in the inner cavity of the outer screw sleeve 1 and gradually approach the position of the U-shaped clamping plate 201. It will first contact the extending part of the U-shaped clamping plate 201. Under the action of the thrust, the extending part will cooperate with the weakening part 205 to turn upwards. When the extending part turns, it will also be squeezed against the hollow frame 206. The inside of the hollow frame 206 is hollow, so it will also squeeze against the edge of the flat end of the inner core fixing screw 2. When the extending part gradually turns to the vertical, the hollow frame 206 will slide into the inside of the U-shaped clamping plate 201. At this time, the hollow frame 206 is no longer squeezed and returns to its original state. The inner core fixing screw 2 continues to slide. When the top of the inner core fixing screw 2 contacts the protruding end of the buffer arc pad 203, under the action of the thrust, the protruding end will deform and squeeze upwards. During the squeezing process, the bottom of the flat end of the inner core fixing screw 2 will abut against the extending part of the U-shaped clamping plate 201 that has returned to its original state. The extending part will support a part of the bottom of the flat end of the inner core fixing screw 2, and most of the bottom of the flat end of the inner core fixing screw 2 will be supported by the lower end of the U-shaped clamping plate 201, and the key position is directly above the elastic piece 204. Through the deformation of the elastic piece 204, it can ensure to the greatest extent that the thrust during the clamping of the inner core fixing screw 2 is weakened, thereby reducing the damage to the patient's fracture end caused by the counter impact. In this way, the inner core fixing screw 2 will no longer slide upwards, which is the shortest distance between the outer screw sleeve 1 and the inner core fixing screw 2, thus effectively adjusting the distance. It is convenient and can also reduce the damage to the patient to the greatest extent, improving the practicability and convenience of the device.

[0055] If the patient is a developing teenager or in a situation where it needs to be removed after recovery, we usually pull the top position of the telescopic rod 3 and pull it outwards. During the pulling process, the telescopic rod 3 will be gradually pulled out. The retaining piece 302 is fixed on the surface of the telescopic rod 3, so the retaining piece 302 will move synchronously with the pulling of the telescopic rod 3. When it moves to the active rubber plug 301, it will abut against the bottom of the active rubber plug 301. In the normal state, the active rubber plug 301 has stability and can withstand a certain pressure, so as to ensure that when the telescopic rod 3 shakes slightly, the active rubber plug 301 can give a limit. When fixing the fracture end, it is necessary to continuously reduce the distance to generate a pressurizing effect.

[0056] The present invention covers any alternatives, modifications, equivalent methods and solutions made on the essence and scope of the present invention. For the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention. However, those skilled in the art can fully understand the present invention without the description of these details. In addition, well-known methods, processes, procedures, components and circuits are not described in detail to avoid unnecessary confusion to the essence of the present invention.

[0057] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A sleeve combined tension-compression internal fixation screw, comprising an outer screw sleeve, characterized in that, The inner cavity of the outer screw sleeve is slidably connected with an inner core fixing screw. The middle part of the top end of the inner core fixing screw is fixedly connected with a telescopic rod. The middle part of the inner cavity of the outer screw sleeve is fixedly connected with an arc-shaped sleeve plate; A limit locking component, which is used to shorten the distance between the outer screw sleeve and the two ends of the fracture. The limit locking component is connected with the outer screw sleeve; The limit locking includes a first limit part opened at the bent end of the arc-shaped sleeve plate. A second limit part is opened at the lower bent end of the arc-shaped sleeve plate. A correction block is fixedly connected to the inner cavity of the outer screw sleeve close to the end of the arc-shaped sleeve plate; An adapter block is fixedly connected to the inner cavity of the outer screw sleeve close to the correction block. A clamping groove is opened at the upper bent end of the adapter block. A U-shaped limit block is fixedly connected to the inner cavity of the outer screw sleeve close to the adapter block; The arc-shaped sleeve plate is made of plastic and its inner cavity is hollow. The first limit part and the second limit part are symmetrically distributed horizontally through the middle part of the arc-shaped sleeve plate. One end of the correction block far from the inner wall of the outer screw sleeve is arc-shaped, and a transverse groove is opened in the middle of the arc; The length of the opened clamping groove is half of that of the adapter block. The U-shaped limit block is made of plastic, and its upper and lower bent ends are provided with hooks; 2. The sleeve combined tension-compression internal fixation screw according to claim 1, characterized in that, The outer surface of the top of the inner core fixing screw is clamped with a U-shaped clamping plate. A protection plate is fixedly connected to the side surface of the upper bent end of the U-shaped clamping plate. A buffer arc pad is fixedly connected to the bottom of the protection plate; 3. The sleeve combined tension-compression internal fixation screw according to claim 2, wherein An elastic sheet is fixedly connected to the inner cavity of the lower bent end of the U-shaped clamping plate. A weakening part is opened at the lower bent end of the U-shaped clamping plate close to the elastic sheet. A hollow frame is fixedly connected to the top end of the inner core fixing screw; 4. The sleeve combined tension-compression internal fixation screw according to claim 1, wherein An active rubber plug is fixedly connected to the inner surface of the telescopic rod close to the top end of the outer screw sleeve. A blocking piece is fixedly connected to the middle part of the bottom end of the active rubber plug; 5. The sleeve combined tension-compression internal fixation screw according to claim 2, wherein The opposite side of the U-shaped clamping plate clamped with the inner core fixing screw is fixedly connected to the inner cavity of the outer screw sleeve. The upper and lower bent ends of the U-shaped clamping plate are provided with hollow shapes. The contact end of the buffer arc pad and the protection plate is flat, and its opposite side is an outwardly convex arc and is hollow inside; 6. The sleeve combined tension-compression internal fixation screw according to claim 3, characterized in that, The elastic sheet is fixedly connected to the inner cavity of the lower bent end of the U-shaped clamping plate. The middle part of the hollow frame is hollow, and the shape of the hollow frame is adapted to the outer surface shape of the top of the inner core fixing screw;

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