A type of bone screw

Abstract

This utility model discloses a bone screw, comprising: a screw body, which is columnar, with threads on its outer periphery and a plurality of helical grooves evenly distributed on its outer periphery. The helical grooves spirally surround the screw body and spirally penetrate the screw body along its axial direction. This bone screw can effectively reduce implantation resistance while facilitating bone tunnel repair and preventing dislodgement.

Description

Technical Field

[0001] This utility model belongs to the field of medical devices, specifically relating to a bone screw. Background Technology

[0002] Currently, bone screws on the market can be divided into two types: traditional metal bone screws and emerging biomedical absorbable polymer bone screws. Metal bone screws require a second surgery for removal, so the product needs both a smooth surface and intact threads to facilitate removal after bone repair. Absorbable bone screws can be absorbed by the body, avoiding the risks of a second removal surgery. However, current absorbable bone screws on the market also use the same structural design as metal bone screws, which brings some problems. For example, the breaking torque of absorbable bone screws is lower than that of metal screws; the intact thread design increases the resistance to screwing in absorbable bone screws or requires a larger tolerance between the bone tap and the absorbable bone screw; at the same time, the intact thread design essentially fills the bone tunnel completely, which is not conducive to bone tunnel repair, and if the bone healing and repair speed is slow, there is also a risk of rotation and loosening. Based on these problems, it is necessary to reconsider the innovative design of absorbable products.

[0003] Therefore, providing a bone screw that can effectively reduce implantation resistance, facilitate bone tunnel repair, and prevent dislodgement is a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0004] This invention provides a bone screw that can effectively reduce implantation resistance while facilitating bone tunnel repair and preventing dislodgement.

[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0006] A bone screw includes: a screw body, which is columnar, with threads on the outer periphery of the screw body, and a plurality of spiral grooves evenly distributed on the outer periphery of the screw body, the spiral grooves spirally surrounding the screw body and spirally penetrating the screw body along the axial direction of the screw body.

[0007] Furthermore, the spiral grooves are distributed in a spiral shape around the outer periphery of the nail body, and the spiral can be a single line or multiple lines.

[0008] Furthermore, when the spiral is a bilinear distribution, the starting points of the spirals coincide or separate.

[0009] Furthermore, when the spiral is distributed in multiple lines, the number of starting points of the spiral is no greater than the total number of spirals.

[0010] Furthermore, the cross-section of the spiral groove is one or more of a rectangular, circular arc, or irregular geometric shape.

[0011] Furthermore, the thread has multiple spaced spirally arranged threads, and the cross-section of the threads is triangular or trapezoidal.

[0012] Furthermore, the height of the thread is not less than half of the half-width of the thread.

[0013] Furthermore, the depth of the spiral groove is no less than half the height of the thread.

[0014] Furthermore, the spacing between each group of adjacent threads is not less than half the height of the thread.

[0015] Furthermore, the helix angle of the spiral is 64° to 75°.

[0016] This invention provides a bone screw with spiral grooves on its surface. During implantation, this ensures a smaller tolerance between the tap and the screw, reducing the likelihood of loosening. The spiral groove design cleans residual material from the bone tunnel into the groove structure, reducing screw insertion resistance and minimizing the risk of screw breakage. Simultaneously, osteoblasts within residual bone fragments in the bone tunnel accelerate bone healing. During the initial healing stage, the spiral groove structure provides space for bone cell growth, resulting in more secure fixation and preventing loosening caused by rotation. The spiral groove design can also carry growth factors, promoting bone healing and serving as a channel for nutrient transport between the two bone surfaces. Furthermore, spiral grooves distribute stress better than straight grooves, preventing fracture due to weakness in any one dimension. The larger surface area of ​​spiral grooves also promotes bone healing, reduces implant weight, and accelerates final degradation. Attached Figure Description

[0017] Figure 1 This is a structural diagram of the bone screw according to Embodiment 1 of this utility model;

[0018] Figure 2 This is a structural diagram of the bone screw in Embodiment 2 of this utility model;

[0019] Figure 3 This is a side view of the bone screw of Embodiment 2 of this utility model;

[0020] Figure 4 This is a structural diagram of the bone screw in Embodiment 3 of this utility model;

[0021] Figure 5 This is a side view of the bone screw of Embodiment 3 of this utility model.

[0022] The reference numerals in the figures include:

[0023] 100—Bone screw; 110—Screw body; 120—Screw head

[0024] 130—Thread; 131—Thread; 140—Helical groove

[0025] 141—Starting point; 132—First thread segment; 133—Second thread segment

[0026] 150—Nail Head Detailed Implementation

[0027] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0028] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0029] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] This utility model provides a bone screw 100 according to a first embodiment, the structure of which is as follows: Figure 1As shown, it mainly includes a nail body 110, which is cylindrical. Threads 130 are provided on the outer periphery of the nail body 110, and multiple spiral grooves 140 are evenly distributed on the outer periphery of the nail body 110. The spiral grooves 140 spirally surround the nail body 110 and spirally penetrate the nail body 110 circumferentially. The nail body 110 can use different shapes depending on the application scenario. Generally, when using compression for fracture fixation and reduction, a bone tunnel is first formed in the bone tissue by drilling (e.g., using an electric drill). Then, a tap is used to tap the bone, and a bone screw is implanted into the bone tunnel to complete the internal fixation of the fracture.

[0032] The bone screw also includes a screw cap 120 and a screw head 150 as the implantation end. The screw cap 120 is connected to the screw body 110 and is integrally formed, which can improve the stability of the bone screw 100.

[0033] The cross-section of the spiral groove 140 can be one or more of a rectangular, arc-shaped, or irregular geometric shape. The spiral grooves 140 are distributed in a spiral pattern around the outer periphery of the nail body 110, and in this embodiment, multiple spiral lines are distributed. The connection point between the spiral line and the nail head 150 serves as the starting point 141 of the spiral line. In this embodiment, the starting points 141 of multiple spiral lines can all coincide, some starting points 141 can coincide, or they can all be non-coincident as shown in the figure. When the starting point is like... Figure 1 When evenly distributed as shown, it can interact more evenly with surrounding tissues during implantation and is less prone to dislodgement.

[0034] The thread 130 has multiple spaced spirally arranged threads 131, the cross-section of which is triangular or trapezoidal. The height of each thread 131 is not less than half its half-height width. The spacing between adjacent threads 131 is not less than half its height. In terms of structural design, the threads 131 of the thread 130 can be thickened, resulting in high locking strength and good pull-out resistance. This solution is impossible to achieve with traditional metal materials. With the addition of spiral grooves 140, traditional metal bone screws cannot be removed a second time after bone healing.

[0035] Preferably, the thread 131 has a chamfered tip, which protects the strength of the thread 131 tip.

[0036] Preferably, the bone screw is made of absorbable material; absorbable material includes polymer absorbable material or a composite of polymer absorbable material and inorganic material.

[0037] Absorbable materials include: polylactic acid, polycaprolactone, polydioxanone, and polyglycolic acid, or one of the following: binary or block copolymers selected from lactide, caprolactone, dioxanone, and glycolide. The inorganic materials include one or both of hydroxyapatite and tricalcium phosphate. Using absorbable materials to manufacture bone screws not only avoids the need for secondary surgery but also avoids many inconveniences caused by residual material in the body, such as the inability to perform MRI scans.

[0038] The second embodiment of the bone screw provided by this utility model has the following structure: Figure 2 and Figure 3 As shown, its general structure is similar to that of the first embodiment. The difference is that the thread 130 of the screw body 110 includes a second thread segment 133 near the screw head 150 and a first thread segment 132 away from the screw head 150. The spacing of the threads 131 of the first thread segment 132 is smaller than the spacing of the threads 131 of the second thread segment 133. The height of the threads 131 of the first thread segment 132 is not constant. It gradually increases along the direction away from the screw head 150. This thread design plays a role in increasing pressure during implantation and preventing dislodgement.

[0039] In this embodiment, the spiral is distributed in a single line, the spiral angle is 72°, the spiral depth is 15mm, and the depth of the spiral groove 140 is equal to the height of the thread 131. This design structure makes the distribution of the spiral groove 140 more reasonable, which helps to reduce the resistance during implantation and also prevents the implantation from falling out.

[0040] The bone screw of the third embodiment provided by this utility model has the following structure: Figure 4 and Figure 5 As shown, its general structure is similar to that of the second embodiment. The difference is that in this embodiment, the spiral is distributed in two lines, and the starting points 141 of the two spirals do not coincide. The spiral angle of the spiral is 73° and the spiral depth is 15mm. The spiral distribution structure of this structure ensures that the spiral grooves 140 are not too dense, which would affect its strength and the firmness of the fixation, nor too sparse, which would fail to achieve the effect of reducing resistance.

[0041] The above content is only a preferred embodiment of this utility model. For those skilled in the art, many changes can be made in the specific implementation and application scope based on the idea of ​​this utility model. As long as these changes do not depart from the concept of this utility model, they all fall within the protection scope of this utility model.

Claims

1. A bone screw, characterized in that, include: The nail body (110) has a thread (130) on its outer periphery and a plurality of spiral grooves (140) are evenly provided on its outer periphery. The spiral grooves (140) are spirally arranged around the nail body (110) and spirally penetrate the nail body (110) along the axial direction of the nail body (110).

2. The bone screw according to claim 1, characterized in that, The spiral grooves (140) are distributed in a spiral shape on the outer periphery of the nail body (110), and the spiral lines can be single or multi-line distributed.

3. The bone screw according to claim 2, characterized in that, The spiral is a double-line distribution, and the starting points (141) of the spirals coincide or separate.

4. The bone screw according to claim 2, characterized in that, The spiral is distributed in multiple lines, and the number of the starting points (141) of the spiral is not greater than the number of the spirals.

5. The bone screw according to claim 3 or 4, characterized in that, The cross-section of the spiral groove (140) is one or more of a rectangular, circular arc, or irregular geometric shape.

6. The bone screw according to claim 2, characterized in that, The thread (130) has a plurality of spaced spirally arranged threads (131), and the cross-section of the threads (131) is triangular or trapezoidal.

7. The bone screw according to claim 6, characterized in that, The height of the thread (131) is not less than half of the half-height width of the thread (131).

8. The bone screw according to claim 7, characterized in that, The depth of the spiral groove (140) is not less than half the height of the thread (131).

9. The bone screw according to claim 8, characterized in that, The spacing between each group of adjacent threads (131) is not less than half the height of the thread (131).

10. The bone screw according to claim 9, characterized in that, The helix angle of the spiral is 64° to 75°.

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