Screw and screw plate system

Abstract

The invention discloses a screw and a screw plate system, the screw comprises a body part, a cap part and an elastic piece, and the near end of the body part is provided with a first driving part; the cap part is provided with a through hole and a second driving part, the near end of the body part is connected into the through hole so that torque can be applied to the body part and the cap part simultaneously or respectively through the first driving part and the second driving part, and the cap part can move in the axial direction of the body part; the elastic piece is arranged on the periphery of the body part in a sleeving mode and limited to move towards the far end of the body part, the elastic piece is arranged close to the cap part, and the elastic piece can deform in the radial direction of the elastic piece. According to the screw provided by the embodiment of the invention, the screw can be screwed into a bone by simultaneously applying torque to the body part and the cap part, and meanwhile, torque can be independently applied to the cap part, so that an implant positioned between the elastic part and the cap part is fastened, and the fitting effect and the fastening effect of the implant and a bone surface are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and particularly relates to a screw and a screw - plate system. Background Art

[0002] In the related art, a screw is usually directly pressed and fixed to a corresponding target plate during application, or a washer and threads are provided between the screw and the target plate to achieve anti - loosening. However, in some cases, it is not suitable to provide a washer and threads between the screw and the target plate. In such cases, when the screw is subjected to the force or vibration generated by human movement, the screw may become loose / backed out. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to some extent.

[0004] To this end, an embodiment of the present invention provides a screw that can improve the tightening effect.

[0005] An embodiment of the present invention also provides a screw - plate system.

[0006] The screw according to the embodiment of the present invention includes:

[0007] A body portion, the proximal end of the body portion having a first driving portion;

[0008] A cap portion, the cap portion having a through - hole and a second driving portion, the proximal end of the body portion being connected in the through - hole so as to apply torques to the body portion and the cap portion simultaneously or separately through the first driving portion and the second driving portion, and the cap portion being axially movable along the body portion;

[0009] An elastic member, the elastic member being sleeved on the circumferential direction of the body portion and being restricted from moving towards the distal end of the body portion, the elastic member being disposed close to the cap portion, and the elastic member being deformable in its radial direction.

[0010] The screw according to the embodiment of the present invention can screw the screw into the bone by applying torques to the body portion and the cap portion simultaneously, and can also apply a torque to the cap portion alone, thereby tightening the implant located between the elastic member and the cap portion, improving the fitting effect and tightening effect between the implant and the bone surface.

[0011] In some embodiments, the elastic member is in an open - ring shape, and the radial dimension of the elastic member can be reduced when it is compressed.

[0012] In some embodiments, the radial dimension of the elastic member gradually decreases from the end close to the cap portion to the end far from the cap portion;

[0013] and / or, the elastic member is in a petal shape;

[0014] And / or, at least one axial end face of the elastic member is provided with anti-slip grooves.

[0015] In some embodiments, the body portion has a limiting portion arranged along its circumferential direction, and one end of the elastic member away from the cap body abuts against the limiting portion.

[0016] In some embodiments, the body portion includes:

[0017] A nail body having an inner cavity;

[0018] A rod body, a partial section of the rod body is connected in the inner cavity, the rod body is axially movable along the nail body, the first driving portion is arranged at one end of the rod body away from the nail body, the proximal end of the rod body is connected in the through hole of the cap body, and the limiting portion is arranged on the rod body.

[0019] In some embodiments, the inner cavity is provided with internal threads, a partial section of the rod body is provided with external threads, and the internal threads and the external threads are threadedly connected.

[0020] In some embodiments, the first driving portion is a counterbore arranged at the proximal end of the body portion for matching with a wrench;

[0021] And / or, a partial section of the through hole is configured as an internal thread section threadedly connected to the body portion, and other sections of the through hole are configured as an internal polygonal interface to form the second driving portion;

[0022] And / or, the radial dimension of the outer wall surface of the cap portion gradually decreases from the end away from the elastic member to the end close to the elastic member.

[0023] In some embodiments, a protrusion is provided on the outer wall surface of the cap portion.

[0024] In some embodiments, the number of the protrusions is at least three and they are arranged along the circumferential direction of the cap portion;

[0025] And / or, the protrusion is strip-shaped, and a preset angle is formed between the length direction of the protrusion and the axis direction of the cap portion.

[0026] A nail plate system includes the screw in any one of the above embodiments, and further includes a bone plate. The bone plate is provided with a ball socket hole penetrating through the bone plate. The body portion can drive the elastic member to pass through the ball socket hole, the cap portion is rotatably arranged in the ball socket hole, and the end face of the elastic member close to the cap portion can abut against one side of the bone plate. Description of the Drawings

[0027] Figure 1 It is a schematic diagram of the screw in an embodiment of the present invention.

[0028] Figure 2 It is a schematic cross-sectional view of the screw according to an embodiment of the present invention.

[0029] Figure 3 It is a schematic three-dimensional view of the screw according to an embodiment of the present invention.

[0030] Figure 4 It is a schematic view of the elastic member according to an embodiment of the present invention.

[0031] Figure 5 It is a schematic view of the body part according to an embodiment of the present invention.

[0032] Figure 6 It is a schematic cross-sectional view of the body part according to an embodiment of the present invention.

[0033] Figure 7 It is a schematic view of the cap part according to an embodiment of the present invention.

[0034] Figure 8 It is a schematic cross-sectional view of the cap part according to an embodiment of the present invention.

[0035] Figure 9 It is a schematic connection view of the screw and the implant (there is a gap between the elastic member and the implant) according to an embodiment of the present invention.

[0036] Figure 10 It is a schematic connection view of the screw and the implant (there is no gap between the elastic member and the implant) according to an embodiment of the present invention.

[0037] Reference numerals:

[0038] 100, screw;

[0039] 1, body part; 11, nail body; 111, internal thread; 12, rod body; 121, external thread; 13, inner cavity; 14, first driving part; 15, limiting part;

[0040] 2, cap part; 21, through hole; 22, second driving part; 23, convex part;

[0041] 3, elastic member; 31, opening; 32, anti-slip groove; 33, inclined surface;

[0042] 4, implant; 41, fixing hole;

[0043] 5, internal thread section. Detailed implementation manners

[0044] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0045] AsFigure 1 and Figure 2 As shown in Figure 2 , the screw 100 according to the embodiment of the present invention includes a body portion 1, a cap portion 2, and an elastic member 3. In this embodiment, taking the example of screwing the screw 100 into the bone to fix the implant 4 in the medical field, the working principle will be described in detail. It should be understood that when the working principles are the same or similar, the screw 100 according to the embodiment of the present invention can also be applied to other fields and be used for connecting corresponding components.

[0046] The proximal end of the body portion 1 has a first driving portion 14, and the first driving portion 14 is used to apply torque to the body portion 1 through an operating tool such as a wrench, so as to facilitate screwing the body portion 1 into the bone. The "proximal end" involved in this embodiment and the following text should be understood as the end that is closer to the operator applying torque to the body portion 1 when operating the screw 100. Correspondingly, the "distal end" should be understood as the end of the body portion 1 that is first screwed into the bone. As shown in the up-and-down direction in the figure, the upper end of the component is the "proximal end", and the lower end of the component is the "distal end". The first driving portion 14 can be a counterbore provided at the proximal end of the body portion 1 and adapted to match the wrench. Optionally, the counterbore can be a flat head slot, a cross slot, an internal hexagonal counterbore, etc. Of course, it can also be other structures for applying torque to the body portion 1.

[0047] The cap portion 2 has a through hole 21 and a second driving portion 22. The proximal end of the body portion 1 is connected in the through hole 21, so as to apply torque to the body portion 1 and the cap portion 2 simultaneously or separately through the first driving portion 14 and the second driving portion 22, and the cap portion 2 is axially movable along the body portion 1. It should be understood that a partial section of the through hole 21 of the cap portion 2 is configured as an internal thread section, so that the proximal end of the body portion 1 is connected in the through hole 21 by thread, and other sections of the through hole 21 are configured as an internal polygonal interface to form the second driving portion 22. The second driving portion 22 is used to apply torque to the cap portion 2 through an operating tool such as a wrench. Optionally, the internal polygonal interface can be an internal square interface, an internal hexagonal interface, a petal-shaped interface, etc. Of course, it can also be other structures for applying torque to the body portion 1.

[0048] Since the proximal end of the body portion 1 is connected in the through hole 21, the first driving portion 14 can be exposed through the through hole 21. Therefore, the first driving portion 14 can be operated alone to apply torque to the body portion 1, the second driving portion 22 can be operated alone to apply torque to the cap portion 2, or an operating tool that cooperates with the first driving portion 14 and the second driving portion 22 simultaneously can be used to apply torque to the body portion 1 and the cap portion 2 simultaneously.

[0049] For example, if the first driving part 14 is a slotted drive and the second driving part 22 is an internal hexagonal interface, the operating tool can be provided with an external hexagonal block and a slotted block arranged coaxially. Among them, the slotted block is used to match the slotted drive, and the external hexagonal block is used to match the internal hexagonal interface. At this time, torque can be applied to both the cap part 2 and the body part 1 simultaneously. When only torque needs to be applied to the cap part 2, an external hexagonal wrench in the prior art can be used. When only torque needs to be applied to the body part 1, a flat head screwdriver in the prior art can be used.

[0050] The elastic member 3 of this embodiment is sleeved on the circumference of the body part 1 and is restricted from moving towards the distal end of the body part 1. The elastic member 3 is arranged close to the cap part 2, and the elastic member 3 can deform radially. It should be understood that a limiting part 15 can be arranged circumferentially on the body part 1, and the end of the elastic member 3 far from the cap body abuts against the limiting part 15, so as to be able to restrict the elastic member 3 from moving towards the distal end of the body part 1. During use, the elastic member 3 can undergo radial deformation when compressed. Initially, the elastic member 3 and the cap part 2 are located on the side of the implant 4 away from the bone surface. As torque is applied to the cap part 2, the cap part 2 will press the elastic member 3 against the fixing hole 41 of the implant 4. The side wall of the fixing hole 41 squeezes the elastic member 3, causing the radial dimension of the elastic member 3 to shrink, so that it can pass through the fixing hole 41 in the implant 4 and move to the side of the implant 4 close to the bone surface.

[0051] The body part 1 of the screw 100 is screwed into the bone, and the implant 4 is pressed and fixed through the elastic member 3 and the cap part 2. The implant 4 is located between the elastic member 3 and the cap part 2, which can achieve anti-loosening and anti-withdrawal of the screw. When the depth of the screw 100 screwed into the bone reaches the predetermined depth, the implant 4 is pressed between the elastic member 3 and the cap part 2, and at the same time, the elastic member 3 can abut between the bone surface and the implant 4. When the screw 100 is blocked and cannot advance when screwed into the bone, torque can be applied to the cap part 2 alone, so that the implant 4 is pressed between the elastic member 3 and the cap part 2. Since the elastic member 3 is restricted from moving towards the distal end of the body part 1, there may be a certain gap between the elastic member 3 and the bone surface, but it can still ensure that the implant 4 is pressed and fixed between the elastic member 3 and the cap part 2, ensuring the stability of the implant 4.

[0052] The embodiment of the present invention can apply torque to both the body part 1 and the cap part 2 of the screw 100 simultaneously, or apply torque to the body part 1 and the cap part 2 separately, improving the pressing effect between the implant 4, the cap part 2 and the elastic member 3, achieving the purpose of anti-loosening and anti-withdrawal, and improving the fitting effect and fastening effect between the implant 4 and the bone surface.

[0053] Such as Figure 4As shown, in some embodiments, the elastic member 3 has an opening 31 and is in the shape of an open ring. When the elastic member 3 is compressed, the radial dimension of the elastic member 3 can be reduced. In application, the implant 4 has a fixing hole 41, which is a ball-and-socket hole, and the radial dimension of the fixing hole 41 gradually decreases from the end far from the bone surface to the end close to the bone surface. The elastic member 3 and the cap portion 2 are combined on the body portion 1. After the implant 4 is aligned and fitted with the bone surface, the distal end of the body portion 1 is inserted into the fixing hole 41 and abuts against the bone surface. By applying a torque to the body portion 1 and the cap portion 2, the body portion 1 is screwed into the bone and the implant 4 is pressed tightly. During the above tightening process, the elastic member 3 first abuts against the wall surface of the fixing hole 41. As the pressure exerted by the cap portion 2 on the elastic member 3 continuously increases, the elastic member 3 can radially contract under the extrusion of the side wall of the fixing hole 41, the size of the opening 31 decreases, and then it passes through the fixing hole 41 and moves to the side of the implant 4 close to the bone surface. Subsequently, the elastic member 3 returns to its original state, so that the implant 4 is located between the elastic member 3 and the cap portion 2.

[0054] After the screw 100 is screwed into the predetermined depth, by applying a torque to the cap portion 2 alone, the implant 4 can be further pressed tightly, so that the gap between the implant 4 and the elastic member 3 and the cap portion 2 is further reduced, improving the tightening effect.

[0055] The elastic member 3 of this embodiment can realize the reduction of the radial dimension. Therefore, before tightening, the body portion 1, the cap portion 2 and the elastic member 3 can be pre-connected to be integrated, which is convenient for the tightening operation, rather than placing multiple components in position separately and then applying a torque, which can prevent the components from being misaligned or falling off.

[0056] As Figures 1 to 6 As shown, in some embodiments, the body portion 1 includes a nail body 11 and a rod body 12. The nail body 11 has an inner cavity 13; a partial section of the rod body 12 is connected in the inner cavity 13. The rod body 12 is axially movable along the nail body 11. The first driving portion 14 is provided at the end of the rod body 12 far from the nail body 11. The proximal end of the rod body 12 is connected in the through hole 21 of the cap body. The elastic member 3 is sleeved on the circumference of the rod body 12. The outer wall surface of the nail body 11 has an external thread 121 that can be screwed into the bone. The distal end of the nail body 11 is a tip, which is convenient for the nail body 11 to drill into the bone. The inner cavity 13 of the nail body 11 has an internal thread 111 connected to the external thread of the rod body 12, so that the rod body 12 and the nail body 11 are threadedly connected together through the external thread 121 and the internal thread 111. When the screw 100 is screwed into the bone, by applying a torque to the first driving portion 14, the rod body 12 and the nail body 11 can be rotated synchronously. In this embodiment, the elastic member 3 is always sleeved on the circumference of the rod body 12 and is axially limited to restrict the elastic member 3 from moving towards the distal end of the rod body 12.

[0057] As Figure 9As shown, when the implant 4 is pressed against the bone surface by the cap 2, and there is a gap L between the elastic member 3 and the implant 4 or they cannot be effectively pressed and fitted together, the anti-loosening and locking effect of the elastic member 3 will be affected. In this embodiment, after the implant 4 is pressed and fixed, by applying a reverse torque to the rod body 12, the rod body 12 can move relative to the nail body 11 in the direction from the distal end to the proximal end. Since the elastic member 3 is axially limited by the rod body 12, the elastic member 3 can be compressed and closer to the implant 4, eliminating the gap between the elastic member 3 and the implant 4, as Figure 10 shown, so that the elastic member 3 is fully compressed and deformed, improving the anti-loosening effect.

[0058] This embodiment can use the cap 2 to press one side of the implant 4, and use the reverse rotation of the rod body 12 to drive the elastic member 3 to press the other side of the implant 4, so that the implant 4 can be firmly pressed and fixed between the elastic member 3 and the cap 2, fully ensuring the stability of the implant 4.

[0059] The following further details another specific embodiment of the present invention with reference to the accompanying drawings.

[0060] As Figures 1 to 10 shown, a screw 100 includes a body portion 1, a cap 2 and an elastic member 3. Among them, the body portion 1 includes a nail body 11 and a rod body 12.

[0061] The outer wall surface of the nail body 11 has an external thread section that can be screwed into the bone. The distal end of the nail body 11 is a tip. The nail body 11 has a lumen 13 extending from the end of its proximal end towards the distal end, and the lumen 13 has an internal thread section.

[0062] The rod body 12 has a limiting portion 15 arranged along its circumferential direction. The limiting portion 15 is an annular flange arranged on the circumferential direction of the rod body 12, and the radial dimension of the annular flange can be less than or equal to the radial dimension of the nail body 11.

[0063] The section between the annular flange on the rod body 12 and the distal end of the rod body 12 is connected to the lumen 13 by threads. The section between the annular flange of the rod body 12 and the proximal end of the rod body 12 is connected to the cap 2 by threads. When the rod body 12 rotates in the first direction, the rod body 12 can be screwed into the lumen 13 of the nail body 11. When the rod body 12 rotates in the direction opposite to the first direction, the rod body 12 can be screwed out of the lumen 13 of the nail body 11.

[0064] One end of the rod body 12 away from the nail body 11 is provided with a first driving portion 14, and the first driving portion 14 is a slotted crosshead or a Phillips head.

[0065] As Figure 7 and Figure 8As shown, the cap portion 2 has a through hole 21 and a second driving portion 22. A partial section of the through hole 21 is an internal thread section, and the cross-section of other partial sections of the through hole 21 is a regular hexagon, so that it is configured as a regular hexagonal interface, and this regular hexagonal interface serves as the second driving portion 22. The section between the annular flange of the rod body 12 and the proximal end of the rod body 12 is connected to the internal thread section of the through hole 21.

[0066] The radial dimension of the outer wall surface of the cap portion 2 gradually decreases from the end far from the elastic member 3 to the end close to the elastic member 3. For example, the outer wall surface of the cap portion 2 has a conical surface structure in the shape of a bowl. The shape of the outer wall surface of the cap portion 2 is complementary to the shape of the fixing hole 41 on the implant 4. After the implant 4 is fixed to the bone by the screw 100 under compression, the cap portion 2 of the screw 100 is embedded in the fixing hole 41, and the cap portion 2 is substantially flush with the end face of the implant 4.

[0067] Optionally, a protrusion 23 is further provided on the outer wall surface of the cap portion 2. After the cap portion 2 is pressed against and fits with the wall surface of the fixing hole 41 on the implant 4, the protrusion 23 can be engaged with the wall surface of the fixing hole 41 of the implant 4, achieving the effects of anti-loosening and anti-slip. The number of the protrusions 23 is at least three and is arranged along the circumferential direction of the cap portion 2. For example, the number of the protrusions 23 is 3, 4 or 6.

[0068] The protrusion 23 is in a strip shape, and there is a preset angle between the length direction of the protrusion 23 and the axis direction of the cap portion 2. For example, the preset angle is 30°, 35° or 66°, and preferably, the preset angle is 45°.

[0069] As Figure 4 shown, the elastic member 3 is sleeved on the circumference of the rod body 12. In this embodiment, whether the elastic member 3 is in the initial state or in the compressed state, it is located on the side of the annular flange close to the implant 4, preventing the elastic member 3 from moving towards the distal end of the rod body 12.

[0070] The elastic member 3 is in an open-ring shape 31, and the radial dimension of the elastic member 3 gradually decreases from the end close to the cap portion 2 to the end far from the cap portion 2, so that an inclined surface 33 is formed on the side surface of the elastic member 3. When the inclined surface 33 of the elastic member 3 is pressed, it can guide the elastic member 3 to radially contract. Optionally, the elastic member 3 is in a petal shape; compared with directly designing the elastic member 3 as a circular ring, it can increase the end face area in the circumferential direction of the elastic member 3, thereby improving more balanced and stable elasticity.

[0071] Furthermore, an anti-slip groove 32 is provided on the axial end face of the elastic member 3. After the elastic member 3 is compressed, it can achieve anti-rotation, thereby realizing the anti-loosening effect and making the pressing effect between the elastic member 3 and its adjacent components more stable.

[0072] When fixing the implant 4 to the bone, first align the implant 4 with the bone surface, then insert the distal end of the nail body 11 into the fixing hole 41 and abut it against the bone surface. By applying torque to the rod body 12 and the cap portion 2, the nail body 11 is screwed into the bone, and the implant 4 is pressed. During the above tightening process, the inclined surface 33 of the elastic member 3 will first abut against the wall surface of the fixing hole 41. As the pressure exerted by the cap portion 2 on the elastic member 3 continuously increases, the elastic member 3 can radially contract under the extrusion of the side wall of the fixing hole 41, the size of the opening 31 decreases, and then the elastic member 3 will pass through the fixing hole 41 and move to the side of the implant 4 close to the bone surface. Subsequently, the elastic member 3 returns to its original state, making the implant 4 located between the elastic member 3 and the cap portion 2.

[0073] After the implant 4 is tightly fixed, the nail body 11 is screwed into the bone, the cap portion 2 is pressed against one side of the implant 4, the elastic member 3 is pressed against the other side of the implant 4, and the elastic member 3 abuts against the annular flange.

[0074] As Figure 9 and Figure 10 shown, when there is a gap L between the implant 4 and the elastic member 3 or the pressing effect is insufficient, the annular flange, the elastic member 3, the implant 4 and the cap portion 2 can be further close to each other by applying torque to the cap portion 2 or applying reverse torque to the rod body 12, so as to further press and lock the implant 4 to prevent loosening.

[0075] In this embodiment, a nail-plate system is also provided, including the screw 100 in any one of the above embodiments. Specifically, it further includes a bone plate. The bone plate is provided with a ball-and-socket hole penetrating the bone plate. The body portion 1 can drive the elastic member 3 through the ball-and-socket hole. The cap portion 2 is rotatably arranged in the ball-and-socket hole. The end face of the elastic member 3 close to the cap portion 2 can abut against one side of the bone plate. Among them, as Figure 3 shown, the bone plate can be a kind of the implant 4 in the above embodiment. Correspondingly, the ball-and-socket hole is the fixing hole 41 in the above embodiment.

[0076] The bone plate of the nail-plate system cooperates with the screw 100. By applying torque to the body portion 1 and the cap portion 2 simultaneously, the screw 100 is screwed into the bone. At the same time, the bone plate located between the elastic member 3 and the cap portion 2 can also be tightened by applying torque to the cap portion 2 alone, improving the fitting effect and tightening effect between the bone plate and the bone surface.

[0077] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is 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, and therefore should not be construed as a limitation to the present invention.

[0078] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0079] In the present invention, unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or capable of communicating with each other; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0081] In the present invention, terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example 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 can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0082] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A screw, characterized in that: include: A main body, wherein a proximal end of the main body has a first driving portion; A cap portion, the cap portion having a through hole and a second driving portion, the proximal end of the body portion being connected to the through hole, so that the first driving portion and the second driving portion simultaneously or separately apply torque to the body portion and the cap portion, and the cap portion is movable along the axial direction of the body portion; An elastic member is sleeved on the circumference of the main body and is restricted from moving toward the distal end of the main body. The elastic member is arranged close to the cap and can be deformed in its radial direction.

2. The screw according to claim 1, characterized in that The elastic member is in the shape of an open ring, and the radial dimension of the elastic member can be reduced when the elastic member is under pressure.

3. The screw according to claim 2, characterized in that: The radial dimension of the elastic member gradually decreases from an end close to the cap portion to an end away from the cap portion; And / or, the elastic member is in a petal shape; And / or, at least one axial end surface of the elastic member has an anti-slip groove.

4. The screw according to claim 1, characterized in that The main body has a limiting portion arranged along its circumference, and one end of the elastic member away from the cap body abuts against the limiting portion.

5. The screw according to claim 4, characterized in that The main body comprises: A nail body having an inner cavity; A rod body, a partial section of which is connected in the inner cavity, the rod body is movable along the axial direction of the nail body, the first driving part is arranged at an end of the rod body away from the nail body, the proximal end of the rod body is connected in the through hole of the cap body, and the limiting part is arranged on the rod body.

6. The screw according to claim 5, characterized in that The inner cavity is provided with an internal thread, and a partial section of the rod body is provided with an external thread, and the internal thread and the external thread are threadedly connected.

7. The screw according to claim 1, characterized in that The first driving portion is a recessed groove disposed at the proximal end of the main body portion and used to match a wrench; And / or, some sections of the through hole are configured as internal thread sections threadedly connected to the main body, and other sections of the through hole are configured as internal polygon interfaces to form the second driving portion; And / or, the radial dimension of the outer wall surface of the cap portion gradually decreases from an end away from the elastic member to an end close to the elastic member.

8. The screw according to claim 7, characterized in that A protrusion is arranged on the outer wall surface of the cap.

9. The screw according to claim 8, characterized in that The number of the protrusions is at least three and they are arranged along the circumferential direction of the cap portion; And / or, the protrusion is in the shape of an elongated strip, and a preset angle is formed between the length direction of the protrusion and the axial direction of the cap portion.

10. A nail plate system, characterized in that: It includes the screw described in any one of claims 1-9, and also includes a bone plate, the bone plate is provided with a ball and socket hole passing through the bone plate, the main body can drive the elastic member to pass through the ball and socket hole, the cap can be rotatably arranged in the ball and socket hole, and the end face of the elastic member close to the cap can be pressed against one side of the bone plate.

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