Bone plate device for preventing screw backout

Abstract

This utility model relates to the field of medical devices, and in particular to a bone plate device for preventing screws from loosening and retracting. It includes a bone plate body with screw holes. An elastic limiting structure is provided on the side of the bone plate body near the screw holes. The elastic limiting structure includes a groove, a limiting block, and a spring. The groove is radially opened along the screw holes and communicates with them. The limiting block is slidably disposed in the groove. A lower groove is formed on the upper surface of the groove bottom, and an upper groove is formed on the lower surface of the limiting block. The upper and lower grooves, when closed, form a chamber for installing the spring. The spring abuts against the inner wall of the chamber radially along the screw holes, pushing the limiting block towards the center of the screw holes. The end of the limiting block has a limiting protrusion extending a certain distance towards the center of the screw holes. The limiting protrusion covers the top of the screw head, thereby limiting the screw. This utility model features a simple structure, does not damage the original dimensions of the medical device, does not occupy additional space, and is automatically adjustable.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, and in particular to a bone plate device for preventing screws from loosening and retracting. Background Technology

[0002] In medical practice, bone plates and screws are often used to fix fractures. Fracture patients need appropriate exercise to help with recovery. Daily life and rehabilitation training may cause screws to loosen to varying degrees. When the loosening reaches a certain degree, medical intervention is needed to tighten them again, which may cause secondary damage to the patient.

[0003] Existing medical or non-medical limiting structures are essentially of two types: one is to fit a locking washer on the screw or to limit the screw through an auxiliary tool. The former, with its locking washer, creates a gap between the screw and the mounting position, which poses a risk of bacterial growth. The latter is bulky and has a limited range of applications, such as the pressure-type locking steel plate disclosed in Chinese patent document CN208838138U and the spring-locking bone plate assembly disclosed in Chinese patent document CN217744553U. Utility Model Content

[0004] The technical problem to be solved by this utility model is: in order to solve the problem that existing screws are prone to loosening and retraction after installation, a bone plate device is provided to prevent screws from loosening and retraction.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a bone plate device for preventing screws from loosening and retracting, including a bone plate body with a screw hole. An elastic limiting structure is provided on the side of the bone plate body of the screw hole. The elastic limiting structure includes a sliding groove, a limiting block, and a spring. The sliding groove is opened radially along the screw hole and communicates with the screw hole. The limiting block is slidably disposed in the sliding groove. A lower groove is opened on the upper surface of the bottom of the sliding groove, and an upper groove is opened on the lower surface of the limiting block. The upper and lower grooves are closed to form a chamber for installing the spring. The spring abuts against the inner wall of the chamber radially along the screw hole, pushing the limiting block to move toward the center of the screw hole. The end of the limiting block has a limiting protrusion extending a certain distance toward the center of the screw hole. The limiting protrusion covers the top of the screw head, thereby limiting the screw.

[0006] Furthermore, the upper and lower grooves have the same external dimensions and opening depth.

[0007] Furthermore, the spring is simultaneously pressed against the inner walls of the upper and lower grooves along the radial direction of the screw hole.

[0008] Furthermore, the spring is an S-shaped spring.

[0009] Furthermore, the upper limiting block and / or the lower sliding groove of the S-shaped spring are provided with through holes for rotating and adjusting the S-shaped spring.

[0010] Furthermore, the through hole is located in the central region of the S-shaped spring.

[0011] Furthermore, the upper surface of the limiting protrusion is an arc surface with an inclined angle.

[0012] The beneficial effects of this utility model are: This utility model provides a bone plate device for preventing screw loosening and retraction, which features a simple structure, does not damage the original medical device dimensions, does not occupy additional space, and is automatically adjustable. Specifically:

[0013] First, this invention will not affect the size of the original medical device, so medical personnel do not need to consider installation issues; second, it does not require additional space for installation, so it will not cause additional burden to the patient; finally, the tightness of the screw limit is automatically adjusted by the spring, so the patient will not feel any discomfort. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the structure of this utility model. Figure 1 ;

[0016] Figure 2 This is a schematic diagram of the structure of this utility model. Figure 2 ;

[0017] Figure 3 yes Figure 1 Sectional view at point AA;

[0018] Figure 4 yes Figure 3 Enlarged view of point B in the middle;

[0019] Figure 5 yes Figure 4 A schematic diagram of the structure after removing the S-shaped spring;

[0020] Figure 6 This is a schematic diagram of the structure of an S-shaped spring;

[0021] Figure 7 This is a three-dimensional structural schematic diagram of the present invention;

[0022] Figure 8 This is a three-dimensional structural diagram of the bone plate body of this utility model;

[0023] Figure 9 This is a three-dimensional structural diagram of the limiting block of this utility model;

[0024] In the diagram: 1. Bone plate body; 2. Screw hole; 3. Slide groove; 4. Limiting block; 5. Spring; 6. Lower groove; 7. Upper groove; 8. Limiting protrusion; 9. Through hole. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] Figures 1 to 9 The illustrated bone plate device for preventing screw loosening and retraction includes a bone plate body 1 with screw holes 2. An elastic limiting structure is provided on the bone plate body 1 on the side of the screw holes 2. The elastic limiting structure includes a sliding groove 3, a limiting block 4, and a spring 5. The sliding groove 3 is radially formed along and communicates with the screw holes 2. The limiting block 4 is slidably disposed in the sliding groove 3. A lower groove 6 is formed on the upper surface of the bottom of the sliding groove 3, and an upper groove 7 is formed on the lower surface of the limiting block 4. The upper and lower grooves 7... The outer dimensions and opening depth of 6 are the same. After the upper and lower grooves 7 and 6 are closed, they form a cavity for installing spring 5. Spring 5 is radially abutted against the inner wall of the cavity along the screw hole 2. Specifically, the two ends of spring 3 as the telescopic end abut against the inner walls of the upper groove 7 and the lower groove 6 at the same time. Spring 3 pushes the limiting block 4 to move towards the center of the screw hole. The end of the limiting block 4 has a limiting protrusion 8 that extends a certain distance towards the center of the screw hole 2. In the figure, the upper surface of the limiting protrusion 8 is an arc surface with an inclined angle.

[0027] To reduce the risk of bacterial growth, S-shaped springs are used. The S-shaped springs are placed horizontally in the cavity. Compared with ordinary spiral springs, S-shaped springs have better openness, making it less likely for bacteria to attach and grow. At the same time, S-shaped springs have less lateral deviation when extending and retracting compared to spiral springs, making them less noticeable to patients.

[0028] To further reduce the risk of bacterial growth and expand the applicability of this invention, a through hole 9 for rotating and adjusting the S-shaped spring is provided on the upper limiting block 4 and / or the lower sliding groove 3 of the S-shaped spring. The through hole is usually located in the central area of ​​the S-shaped spring. The through hole 9 firstly allows the medium (usually blood) to flow through the spring 5, so that bacteria are less likely to adhere to and grow at the spring 5. Secondly, the S-shaped spring can be rotated, causing the extension and retraction end of the S-shaped spring to shift, thereby adjusting the extension and rebound force of the limiting block 4 to adapt to more application scenarios. At the same time, the through hole 9 also serves as an installation channel for installing the S-shaped spring.

[0029] Compared to the conventional structure, which places the spring at the rear end of the limiting block and uses the rear end face of the slide groove to push the limiting block toward the center of the screw hole 2, this invention has three advantages:

[0030] First, machining the lower groove 6 and the upper groove 7 on the limiting block 4 and the slide 3 respectively can reduce the shaking of the spring 5 during operation, especially the up and down shaking. Conventional structures require additional limiting to achieve this, and the limiting also has the risk of hindering the normal sliding of the limiting block 4.

[0031] Secondly, the conventional structure does not have a structure to adjust the extension force of spring 5. It can only be achieved by selecting the elastic force of spring 5. It is not practical to set up an adjustment structure while ensuring the sliding distance of limit block 4.

[0032] Third, combining the first and second, this utility model can maximize the sliding stroke of the limiting block 4, occupy the least space to achieve a larger adjustment range of the limiting block 4, and further save space.

[0033] Working principle: When the screw rotates downward, the limiting block 4 will come into contact with the upper surface of the limiting protrusion 8 of the limiting block 4 due to the downward pressure of the screw. Since the upper surface is an arc surface with an inclined angle, the limiting block 4 will retract backward.

[0034] When the screw is screwed in place, the upper surface of the limit block 4 is no longer in contact with the screw. The limit block 4 will extend forward and return to normal due to the spring 5 rebounding. The limiting protrusion 8 of the limit block 4 will cover the top of the screw to prevent the screw from falling off.

[0035] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A bone plate device for preventing screws from loosening and retracting, comprising a bone plate body, wherein screw holes are provided on the bone plate body, characterized in that: An elastic limiting structure is provided on the bone plate body on the side of the screw hole. The elastic limiting structure includes a sliding groove, a limiting block, and a spring. The sliding groove is opened radially along the screw hole and communicates with the screw hole. The limiting block is slidably disposed in the sliding groove. A lower groove is opened on the upper surface of the bottom of the sliding groove, and an upper groove is opened on the lower surface of the limiting block. After the upper and lower grooves are closed, they form a cavity for installing the spring. The spring abuts against the inner wall of the cavity radially along the screw hole and pushes the limiting block to move towards the center of the screw hole. The end of the limiting block has a limiting protrusion extending a certain distance towards the center of the screw hole. The limiting protrusion covers the top of the screw head, thereby limiting the screw.

2. The bone plate device for preventing screw loosening and retraction according to claim 1, characterized in that: The upper and lower grooves have the same external dimensions and opening depth.

3. The bone plate device for preventing screw loosening and retraction according to claim 1, characterized in that: The spring is simultaneously pressed against the inner walls of the upper and lower grooves along the radial direction of the screw hole.

4. The bone plate device for preventing screw loosening and retraction according to claim 1 or 3, characterized in that: The spring is an S-shaped spring.

5. The bone plate device for preventing screw loosening and retraction according to claim 4, characterized in that: The upper limiting block and / or lower sliding groove of the S-shaped spring are provided with through holes for rotating and adjusting the S-shaped spring.

6. The bone plate device for preventing screw loosening and retraction according to claim 5, characterized in that: The through hole is located in the central region of the S-shaped spring.

7. The bone plate device for preventing screw loosening and retraction according to claim 1, characterized in that: The upper surface of the limiting protrusion is an arc surface with an inclined angle.

Images