Interphalangeal joint support anti-rotation nail

Abstract

The present invention discloses an interphalangeal joint supporting anti-rotation nail, which comprises a nail head and a nail body fixedly connected together; the outer peripheral wall of the nail body is provided with threads; the outer peripheral wall of the nail head is concavely provided with two first notches which are axially symmetrically arranged relative to the axis of the nail head, a protruding portion is formed between the two first notches, a second notch is concavely formed on the outer side wall of the protruding portion, and an inverted tooth structure is further provided on the outer side wall of the protruding portion. It has the following advantages: 1. Prevent rigid fracture at this position due to excessive pressure, and effectively prevent phalanx rotation, improving the stability of fixation; 2. Simple and convenient to operate, ensuring the fusion of the interphalangeal joint.

Description

Technical Field

[0001] The present invention relates to medical devices, and in particular to an interphalangeal joint support anti-rotation nail. Background Art

[0002] When treating toe pain caused by deformities such as hammer toe, claw toe or mallet toe in the foot, and the patient is unable to walk normally, clinical treatment often uses open reduction and Kirschner wire fixation. Although this fixation method is simple, the fixation is unstable, prone to rotational displacement, and the tip of the Kirschner wire is exposed outside the skin, which is prone to infection, difficult for postoperative care, difficult for the patient to wear shoes after the operation, unable to get out of bed to walk in the short term, the joint surface fusion is unstable, prone to non-fusion of the interphalangeal joint, and the surgical treatment effect is not ideal or even fails. In view of the above deficiencies, some solutions have been proposed:

[0003] For example, CN203885606U discloses a screw for correcting hammer toe, which includes a nail head and a nail body. The nail head has a serrated edge; the first end of the nail body is integrally formed with the nail head, the outer wall of the nail body is provided with threads, and a hole that penetrates both the nail body and the nail head is axially provided along the nail body. The cross-sectional shape of the nail head is trident-shaped, and the shapes of the three edges of the outermost end of the nail head parallel to the axis of the nail head are serrated. In this solution, the cross-sectional shape of the nail head is trident-shaped. On the one hand, the bone removal amount is relatively large, and the stress dispersion effect on the bone needs to be improved; on the other hand, the anti-rotation effect also needs to be improved. Summary of the Invention

[0004] The present invention provides an interphalangeal joint support anti-rotation nail, which overcomes the deficiencies of the screw for correcting hammer toe in the background art.

[0005] The technical solution adopted by the present invention to solve its technical problems is:

[0006] The interphalangeal joint support anti-rotation nail includes a nail head and a nail body fixedly connected together; the outer peripheral wall of the nail body is provided with threads; the outer peripheral wall of the nail head is concavely provided with two first notches arranged axially symmetrically with respect to the axis of the nail head, a convex portion is formed between the two first notches, a second notch is concavely formed on the outer side wall of the convex portion, and an inverted tooth structure is further provided on the outer side wall of the convex portion.

[0007] In one embodiment: the cross-section of the second notch is in a shape similar to an outward V shape.

[0008] In one embodiment: the cross-sectional contour of the second notch includes an arc segment with the center outside and two straight line segments respectively formed by extending the tangents at both ends of the arc segment.

[0009] In one embodiment: the central angle of the second notch is 30 to 85 degrees.

[0010] In one embodiment: The side wall of the first notch is a cylindrical arc surface with an opening facing outward.

[0011] In one embodiment: The end of the nail head is in a wedge-shaped structure.

[0012] In one embodiment: The axial planes of the two first notches are arranged along a first direction, the axial planes of the two second notches are arranged along a second direction, and the first direction and the second direction are perpendicular.

[0013] In one embodiment: The axial planes of the two first notches are arranged along a first direction, the axial planes of the two second notches are arranged along a second direction, and the first direction and the second direction are perpendicular; the end of the nail head is in a wedge-shaped structure, and the trailing side edge of the wedge-shaped structure is arranged along the first direction.

[0014] In one embodiment: A through hole is provided that penetrates the nail head and the nail body, and the through hole is arranged along the axis of the nail head and the axis of the nail body.

[0015] In one embodiment: A through hole is provided that penetrates the nail head and the nail body, and the through hole is arranged along the axis of the nail head and the axis of the nail body, and moreover, the end of the nail head is in a wedge-shaped structure.

[0016] In one embodiment: The outer diameter of the nail body is greater than the outer diameter of the nail head.

[0017] In one embodiment: At least three cutting edges are provided at the end of the nail body.

[0018] In one embodiment: The axis of the nail body coincides with the axis of the nail head.

[0019] In one embodiment: The axis of the nail body intersects the axis of the nail head, and the intersection angle is 5 to 30 degrees.

[0020] Compared with the background art, the present technical solution has the following advantages:

[0021] On the outer peripheral wall of the nail head, two first notches are concavely provided and are axially symmetrically arranged with respect to the axis of the nail head. A protruding portion is formed between the two first notches. A second notch is concavely formed on the outer side wall of the protruding portion, and a reverse tooth structure is further provided on the outer side wall of the protruding portion. Therefore, the deficiencies existing in the background art are overcome and the following technical effects are produced: First, the protruding portion forms a structure similar to an inverted V shape. The opening of the inverted V shape can effectively increase the anti-rotation performance, and the elastic performance with slight deformation of the inverted V shape structure enables the inverted V shape structure to generate up and down elastic deformation when pressure is applied to this position, so as to prevent rigid fracture at this position due to excessive pressure. The structures similar to inverted V shapes of the two protruding portions make the nail head have a tip quadrangular pyramid design, effectively preventing phalanx rotation and improving the stability of fixation; Second, the operation is simple and convenient, ensuring interphalangeal joint fusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the drawings and specific embodiments.

[0023] Figure 1 It is one of the three-dimensional schematic diagrams of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0024] Figure 2 It is the second three-dimensional schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0025] Figure 3 It is the third three-dimensional schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0026] Figure 4 It is the front view schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0027] Figure 5 It is the left view schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0028] Figure 6 It is Figure 2 the partial enlarged schematic diagram of.

[0029] Figure 7 It is Figure 3 the partial enlarged schematic diagram of.

[0030] Figure 8 It is Figure 4 the partial enlarged schematic diagram of.

[0031] Figure 9 It is the usage schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 1.

[0032] Figure 10 It is the three-dimensional schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 2.

[0033] Figure 11 It is the front view schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 2.

[0034] Figure 12 It is the usage schematic diagram of the interphalangeal joint support anti-rotation nail in Embodiment 2. Detailed implementation mode

[0035] Embodiment 1

[0036] Please refer to Figures 1 to 8 , the interphalangeal joint support anti-rotation nail includes a nail head 10 and a nail body 20 fixedly connected together, such as integrally formed, and the outer diameter of the nail body 20 is larger than the outer diameter of the nail head 10. The anti-rotation nail is provided with a through hole 30 penetrating through the nail head 10 and the nail body 20. The through hole 30 is arranged along the axis of the nail head 10 and the axis of the nail body 20. The cross section of the through hole 30 is circular, and the center of the circle is located on the axis of the anti-rotation nail; the through hole 30 is provided to cooperate with the guide pin to ensure the position during implantation, facilitating clinical use. In this embodiment, the axis of the nail body 20 coincides with the axis of the nail head 10.

[0037] The outer peripheral wall of the nail body 20 is provided with a thread 21, and at least three cutting edges 22 are provided at the end of the nail body 20. If three cutting edges 22 are provided, the cutting angles of the respective cutting edges 22 are different. In this embodiment, the cutting edge 22 has a self-tapping and self-drilling function, and there are 3 sharp edges at the forefront of the multi-angle cutting edge, which can perform positioning and rapid cutting and screwing functions. The thread 21 adopts a cancellous bone thread design to enhance the holding force.

[0038] The outer peripheral wall of the nail head 10 is concavely provided with two first notches 11 arranged axially symmetrically with respect to the axis of the nail head 10. A protruding portion 12 is formed between the two first notches 11. A second notch 13 is concavely formed on the outer side wall of the protruding portion 12, and a reverse tooth structure 14 is further provided on the outer side wall of the protruding portion 12. Among them: two first notches 11 and two second notches 13 are provided, so that the protruding portion 12 forms a structure similar to an eight-character shape. First, the opening of the eight-character shape can effectively increase the anti-rotation performance. Second, the eight-character shape structure has an elastic performance with micro-deformation. Therefore, when pressure is applied to this position, the eight-character shape structure can produce up-and-down elastic deformation to prevent rigid fracture at this position due to excessive pressure. Third, the structure similar to an eight-character shape of the two protruding portions makes the nail head 10 have a pointed quadrangular pyramid design, effectively preventing phalangeal rotation and improving the stability of fixation. A reverse tooth structure 14 is further provided on the outer side wall of the protruding portion 12 to effectively prevent the implant from slipping out; the reverse tooth angle of the reverse tooth structure 14 is between 0 and 90°.

[0039] The side wall of the first notch 11 is a cylindrical arc surface with an opening facing outwards; the cross-sectional contour of the second notch 13 includes an arc segment 131 with a center outside and two straight line segments 132 respectively formed by extending the tangents at both ends of the arc segment, so that the cross-section of the second notch presents a structure similar to an outer eight-character shape. Moreover, the radius of the arc segment 131 is smaller than the radius of the cylindrical arc surface. The central angle of the second notch 13 is 30 to 85 degrees. Among them, the side wall of the first notch 11 being a cylindrical arc surface with an opening facing outwards can reduce the amount of bone removed, disperse the stress at this position, and reduce the possibility of bone fracture caused by stress.

[0040] The axial planes of the two first notches 11 are arranged in a first direction, and the axial planes of the two second notches 13 are arranged in a second direction, and the first direction and the second direction are perpendicular; the end of the nail head 10 has a wedge-shaped structure 15, and the trailing side edge of the wedge-shaped structure is arranged in the first direction. Since the end of the nail head 10 has a wedge-shaped structure and the anti-rotation nail is provided with a through hole 30 penetrating the nail head 10 and the nail body 20, a groove 151 is formed in the middle of the end of the nail head 10, and a pointed tooth 152 is formed at the end of the nail head 10. The pointed tooth can perform a positioning and indicating function on the end face of the opposite bone, and the wedge-shaped structure is convenient for insertion.

[0041] Figure 9 It is a schematic diagram of the use of the interphalangeal joint support anti-rotation nail in Embodiment 1. The interphalangeal joint support anti-rotation nail is screwed into the interphalangeal joint 40.

[0042] Embodiment 2

[0043] Please refer to Figure 10 and Figure 11 , which is different from the first embodiment in that the axes of the nail body 20 and the nail head 10 intersect, and the intersection angle is 5 to 30 degrees, such as 10 degrees. Figure 12 FIG. is a schematic view of the use of the interphalangeal joint support anti-rotation nail of the second embodiment, and the interphalangeal joint support anti-rotation nail is screwed into the interphalangeal joint 40.

[0044] The above is only a preferred embodiment of the present invention, and thus the scope of implementation of the present invention cannot be limited thereby. That is, equivalent changes and modifications made according to the scope of the present invention patent and the content of the specification should still fall within the scope covered by the present invention.

Claims

1. The interphalangeal joint support anti-rotation nail comprises a nail head and a nail body fixedly connected together; the outer peripheral wall of the nail body is provided with threads; It is characterized in that: The outer peripheral wall of the nail head is concavely provided with two first notches which are axially symmetrically arranged relative to the axis of the nail head. There are two protruding parts formed between the two first notches. The outer side walls of the two protruding parts are respectively concavely provided with two second notches, so that each protruding part forms a structure similar to an inverted V shape. This structure similar to an inverted V shape has elastic performance with micro-deformation and can produce elastic deformation when subjected to pressure. The outer side wall of the protruding part is also provided with an inverted tooth structure; the cross-sections of the two first notches are respectively cylindrical arc surfaces with openings facing outwards; the cross-sections of the two second notches respectively include a structure similar to an outward inverted V shape. The cross-section contour of the second notch includes an arc segment with the center outside and two straight line segments respectively formed by extending the tangents at both ends of the arc segment. The radius of the arc segment is smaller than the radius of the cylindrical arc surface; the central angle of the second notch is 30 - 85 degrees.

2. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The end of the nail head is in a wedge-shaped structure.

3. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The axial planes of the two first notches are arranged along a first direction, and the axial planes of the two second notches are arranged along a second direction, and the first direction and the second direction are perpendicular.

4. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The axial planes of the two first notches are arranged along a first direction, and the axial planes of the two second notches are arranged along a second direction, and the first direction and the second direction are perpendicular; the end of the nail head is in a wedge-shaped structure, and the trailing edge of the wedge-shaped structure is arranged along the first direction.

5. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: There is a through hole passing through the nail head and the nail body, and the through hole is arranged along the axis of the nail head and the axis of the nail body.

6. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: There is a through hole passing through the nail head and the nail body, and the through hole is arranged along the axis of the nail head and the axis of the nail body, and the end of the nail head is in a wedge-shaped structure.

7. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The outer diameter of the nail body is larger than the outer diameter of the nail head.

8. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: At least three cutting edges are provided at the end of the nail body.

9. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The axis of the nail body coincides with the axis of the nail head.

10. The interphalangeal joint support anti-rotation nail according to claim 1, It is characterized in that: The axis of the nail body intersects with the axis of the nail head, and the intersection angle is 5 - 30 degrees.

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