plate

The plate's innovative hole design with projections and grooves enables secure bolt fixation at any angle, addressing the limitations of existing bone plates by adapting to individual bone variations for effective fracture repair.

JP2026061954APending Publication Date: 2026-04-09ME SYST CO LTD
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-09-30
Publication Date
2026-04-09

AI Technical Summary

Technical Problem

Existing bone plates are limited in their ability to adjust the angle of bolt fixation, as the fixing holes can only accommodate a specific range of angles due to the design of threaded regions and recesses, limiting flexibility in securing the plate to varying bone structures.

Method used

The plate features a hole design with multiple projections and grooves along its inner surface, allowing for the bolt to engage at any angle through plastic deformation of these projections when inserted, ensuring secure fixation regardless of the bone's position or shape.

Benefits of technology

The plate can securely fix bolts at any angle, accommodating varying bone structures, thereby promoting effective repair and treatment of fractures by allowing for precise and flexible attachment.

✦ Generated by Eureka AI based on patent content.

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Abstract

A plate is provided that allows bolts to be fixed at any angle. [Solution] The plate 10 has a hole 70 for inserting a bolt having a threaded portion, and the hole 70 has a first projection positioned along the inner surface of the hole 70. When the bolt is inserted into the hole 70, the threaded portion comes into contact with the first projection, and the first projection deforms, causing the hole 70 and the bolt to engage, and the plate 10 can be fixed at any angle by allowing the shaft to penetrate into the bone.
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Description

Technical Field

[0001] The present invention relates to a plate for fixing in order to repair a site when bone is deficient due to fracture, osteoporosis, or the like.

Background Art

[0002] The plate promotes repair of a deficient site by fixing the plate so as to span the deficient site in order to repair the site when bone is deficient or fractured.

[0003] In order to attach the plate to a site where bone is deficient, bolts having heads and screw portions on shaft portions may be used. Such a bolt is inserted into a hole provided in the plate and its head is locked to the hole, and the shaft portion is made to penetrate inside the bone, thereby fixing the plate.

[0004] However, the position of the site where bone is deficient or the shape of the bone may vary among individuals, and it is necessary to adjust the position of the bolt. That is, a plate with a hole is applied to the site where bone is deficient, and in some cases, it is required to adjust the angle formed by the bolt and the plate while inserting the bolt while engaging the head of the bolt with the hole.

[0005] As an example of such a plate, a bone plate is disclosed in Japanese Patent Publication No. 2019-526375. This bone plate includes an inner surface configured to face bone, an outer surface opposite to the inner surface, and an inner surface extending from the outer surface to the inner surface, the inner surface defining a fixing hole, the fixing hole extending from the outer surface to the inner surface along the hole's central axis and sized to receive a shaft of the bone anchor extending along the anchor's central axis toward the threaded head of the bone anchor, the inner surface comprising: 1) a tapered threaded region including a plurality of threaded columns spaced circumferentially apart from each other around the hole's central axis and separated from each other by a plurality of corresponding recesses; and 2) the tapered threaded region and the A second region extending between the outer surface and the second region is defined, the second region becoming concave as it extends along both the plane containing the central axis of the hole and the plane perpendicular to the central axis of the hole, wherein 1) the tapered threaded region is configured to screw-fit with the threaded head when the bone anchor is positioned in a first orientation with respect to the central axis of the hole, 2) the tapered threaded region is further configured to screw-fit with the threaded head when the bone anchor is positioned at an angle of a second orientation different from the first orientation with respect to the central axis of the anchor, and 3) the second region is configured to receive compressive force from the compression screw inserted into the fixing hole such that the head of the compression screw abuts against the second region.

[0006] The bone plate described above has a fixing hole, but the fixing hole has a second recessed area, and when an anchor bolt is inserted into the fixing hole and the angle of the anchor is tilted, it can engage while accommodating that tilted angle.

[0007] However, as shown in Figure 8 of the above-mentioned publication, the angle is limited to the ability of the fixing hole and anchor to be screw-fitted with threads that are offset by at least one notch, and the angle cannot be arbitrarily changed. [Prior art documents] [Patent Documents]

[0008] Special Publication No. 2019-526375 [Overview of the project] [Problems that the invention aims to solve]

[0009] This invention was made in view of the above circumstances, and its objective is to provide a plate that can fix a bolt at any angle. [Means for solving the problem]

[0010] To solve the aforementioned problems, the plate in the first aspect has a hole for inserting a bolt having a threaded portion, and the hole has a first projection positioned along the inner surface of the hole, and when the bolt is inserted into the hole the threaded portion comes into contact with the first projection, and the first projection deforms so that the hole and the bolt engage.

[0011] To solve the aforementioned problems, the plate in the second view has a hole for inserting a bolt having a threaded portion, the hole has a first projection positioned along the inner surface of the hole, and a second projection positioned below the first projection along the inner surface of the hole, and when the bolt is inserted into the hole the threaded portion comes into contact with the first projection and the second projection, and the first projection and the second projection deform, thereby engaging the hole and the bolt.

[0012] To solve the aforementioned problems, the plate of the third perspective has a hole for inserting a bolt having a threaded portion, the hole has a first projection positioned along the inner surface of the hole, a second projection positioned below the first projection along the inner surface of the hole, and a third projection positioned below the second projection along the inner surface of the hole, and when the bolt is inserted into the hole, the threaded portion comes into contact with one of the first projection, the second projection, or the third projection, and one of the first projection, the second projection, or the third projection that comes into contact with the threaded portion deforms, thereby engaging the hole and the bolt.

[0013] To solve the aforementioned problems, the plate of the fourth aspect has a hole for inserting a bolt having a threaded portion, the hole has a first projection positioned along the inner surface of the hole, a second projection positioned below the first projection along the inner surface of the hole, a third projection positioned below the second projection along the inner surface of the hole, and a fourth projection positioned below the third projection along the inner surface of the hole, the threaded portion has a barrel shape and a first groove that forms a groove between the first projection and the second projection, and a second The bolt has a groove-shaped second groove between the projection and the third projection, and a groove-shaped third groove between the third projection and the fourth projection. The first groove has a first side surface, the second groove has a second side surface, and the third groove has a third side surface. The first, second, and third side surfaces are inversely tapered. When a bolt is inserted into the hole, any of the first, second, third, or fourth projections that come into contact with the threaded portion deform, causing the hole and the bolt to engage.

[0014] To solve the aforementioned problems, the plate of the fifth aspect has a hole for inserting a bolt having a threaded portion, the hole has a first projection positioned along the inner surface of the hole, a second projection positioned below the first projection along the inner surface of the hole, a third projection positioned below the second projection along the inner surface of the hole, and a fourth projection positioned below the third projection along the inner surface of the hole, the threaded portion has a barrel shape and a first groove that forms a groove between the first projection and the second projection, and a second projection The bolt has a groove-shaped second groove between the starting portion and the third projection, and a groove-shaped third groove between the third projection and the fourth projection. The first groove has a first side surface, the second groove has a second side surface, and the third groove has a third side surface. The first, second, and third side surfaces are inversely tapered. When a bolt is inserted into the hole at an angle, any of the first, second, third, or fourth projections that come into contact with the threaded portion deform, causing the hole and the bolt to engage. [Effects of the Invention]

[0015] As the present invention is configured and operates as described above, it is possible to provide a plate that can fix a bolt at any angle. [Brief explanation of the drawing]

[0016] [Figure 1] This is a perspective view of the plate. [Figure 2] This is a plan view of the plate. [Figure 3] This is a side view of the plate. [Figure 4] A is a cross-sectional view taken along the line IVA-IVA in Figure 2. B is a cross-sectional view taken along the line IVB-IVB in Figure 2. [Figure 5] This is a magnified cross-sectional view of the hole in the plate. [Figure 6] This is a conceptual perspective view showing a plate attached to a bone. [Figure 7] This is a conceptual plan view showing a plate attached to a bone. [Figure 8] It is a conceptual side view of the state where a plate is attached to a bone. [Figure 9] It is a side conceptual perspective view of the state where a plate is attached to a bone. [Figure 10] It is a side conceptual view of the state where a plate is fixed to a bone. [Figure 11] A is a side view of a bolt. B is a plan view of a bolt. [Figure 12] A is a cross-sectional view of the head of a bolt. B is a side view of the head of a bolt before machining the screw part. [Figure 13] It is a cross-sectional view of a bolt. [Figure 14] A is a state diagram where a bolt and a hole part are vertically fitted. B is a state diagram where a bolt and a hole part are inclined and fitted. [Figure 15] It is a partial enlarged conceptual view of the state where a bolt and a hole part are vertically fitted. [Figure 16] It is a partial enlarged conceptual view of the state where a bolt and a hole part are inclined and fitted.

[0017] The plate 10 of this embodiment will be described. The plate 10 of this embodiment has a main body part 20 and a head part 50 and integrally forms them, and the head part 50 is wider than the main body part 20. The plate 10 is used, for example, instead of a plaster or a splint at the fractured part, is applied so as to straddle the fractured part, and by fixing it with a plurality of bolts 100 as will be described later, the treatment of the fracture can be promoted.

[0018] The plate 10 of this embodiment can be made of pure titanium or 64 titanium. The plate 10 has a plurality of hole parts 70 for inserting a plurality of bolts 100. The hole parts 70 are arranged so as to penetrate the front surface 11 and the back surface 12 of the plate 10. Here, the back surface 12 is the part that contacts the bone. In addition, the plate 10 of this embodiment is also preferable as a stainless material.

[0019] The hole 70 has a first projection 81 that is circumferential to its inner surface 71 and has a cross-sectional projection shape, a second projection 82 that is circumferential to its inner surface 71 and has a cross-sectional projection shape, a third projection 83 that is circumferential to its inner surface 71 and has a cross-sectional projection shape, and a fourth projection 84 that is circumferential to its inner surface 71 and has a cross-sectional projection shape. The position of the second projection 82 from the center C is preferably, for example, 1.5 millimeters. The same applies to the third projection 83 and the fourth projection 84.

[0020] Furthermore, the hole 70 has a groove-shaped first groove 91 arranged around its inner surface 71 between the first projection 81 and the second projection 82, a groove-shaped second groove 92 arranged around its inner surface 71 between the second projection 82 and the third projection 83, and a groove-shaped third groove 93 arranged around its inner surface 71 between the third projection 83 and the fourth projection 84.

[0021] In other words, on its inner surface 71, the hole 70 has the following arrangement of projections: a first projection 81, a first groove 91, a second projection 82, a second groove 92, a third projection 83, a third groove 93, and a fourth projection 84, in that order from the upper U direction to the lower D direction. It is preferable that these projections do not constitute a screw, but rather are arranged independently around the inner surface 71. The number of projections is not limited to these.

[0022] Furthermore, the first groove 91 has a first side surface portion 91a, which is the side surface of the first groove 91. The second groove 92 has a second side surface portion 92a, which is the side surface of the second groove 92. The third groove 93 has a second side surface portion 93a, which is the side surface of the third groove 93. The positions T1 of the first side surface portion 91a, T2 of the second side surface portion 92a, and T3 of the third side surface portion 93a from the center C are arranged to become shorter in the order T1, T2, and T3. Therefore, the position of the first inner wall portion 91a, which is the inner wall of the first groove 91, and the position of the second inner wall portion 92a, which is the inner wall of the second groove 92, are such that the position of the first inner wall portion 91a is outward from the position of the second inner wall portion 92a. In other words, the diameter of the first groove 91 is larger than the diameter of the second groove 92.

[0023] The position of the second inner wall portion 92a, which is the inner wall of the second groove portion 92, and the position of the third inner wall portion 93a, which is the inner wall of the third groove portion 93, are such that the second inner wall portion 92a is positioned further outward than the third inner wall portion 93a. In other words, the diameter of the second groove portion 92 is larger than the diameter of the third groove portion 93.

[0024] Thus, the first inner wall portion 91a, the second inner wall portion 92a, and the third inner wall portion 93a are arranged in such a way that their diameter decreases from the upward U direction to the downward D direction. That is, the first inner wall portion 91a, the second inner wall portion 92a, and the third inner wall portion 93a are arranged in such a way that they approach the center C from the upward U direction to the downward D direction.

[0025] In other words, the grooves are configured to become shallower in the order of the first groove 91, the second groove 92, and the third groove 93. Therefore, the line L1 connecting the first groove 91, the second groove 92, and the third groove 93 exhibits a reverse taper shape, decreasing in diameter from the upward U direction to the downward D direction.

[0026] Furthermore, the hole 70 has a circular opening 75 in plan view, located in the U direction above the first projection 81. The opening 75 serves as an entry point for inserting the bolt 100, which will be described later.

[0027] The amount of protrusion of the first projection 81 and the second projection 82 relative to the center C direction of the hole 70 is such that the amount of protrusion of the second projection 82 is greater than that of the first projection 81.

[0028] Furthermore, the amount of protrusion of the second projection 82 and the third projection 83 relative to the center C direction of the hole 70 is approximately the same. Also, the amount of protrusion of the fourth projection 84 relative to the center C direction is approximately the same as the amount of protrusion of the third projection 83.

[0029] In this embodiment, the radius of the opening 75 of the hole 70 in the plate 10 is preferably 2 millimeters, for example, so that the bolt head 110 of the bolt 100, which will be described later, can be placed there.

[0030] Furthermore, the thickness S1 of the first groove 91 and the second projection 82 is preferably 0.4 millimeters in this embodiment, and the thickness S2 of the second groove 92 and the third groove 93 is also preferably 0.4 millimeters in this embodiment.

[0031] The plate 10 also has screw holes 76 for attaching a block guide (not shown). Furthermore, the plate 10 has elongated adjustment holes 77 for attaching it to, for example, the radius 500.

[0032] Furthermore, the plate 10 has a concave recess 51 on the head 50 of the back surface 12. The plate 10 of this embodiment is preferably applied to the radius 500, and is particularly preferably applied to fractures of the distal end 510 of the radius 500. Also, by positioning the recess 51 to correspond to the distal end 510 of the radius 500, the positioning of the plate 10 can be facilitated. Therefore, when the distal end 510 of the radius 500 has a convex protrusion 511, positioning the plate 10 and the radius 500 can be facilitated by applying the concave recess 51 to the head 50 of the back surface 12 of the plate 10. In addition, the recess 51 can also accommodate fractured bone fragments, so by positioning the recess 51 to accommodate the bone fragments, the repair of the fractured and separated portion can be promoted.

[0033] Furthermore, the tip 55 of the head 50 has multiple claw-shaped locking portions 56. The side 60 of the head also has multiple claw-shaped second locking portions 61. The plate 10 of this embodiment is preferably applied to the treatment of fractures of the distal end 510 of the radius 500. When applied to the distal end 510 of the radius 500, the locking portions 56 can engage with the distal end 510 of the radius 500, and the second locking portions 61 can engage with the side 520 of the radius 500. However, it is not limited to the treatment of the radius 500 and can be applied to other fractures. In addition, the locking portions 56 can engage with, for example, bone fragments fractured and separated from the distal end 510 of the radius 500, thereby pulling the bone fragments closer and promoting the repair of the distal end 510 of the radius 500. Furthermore, the second locking portion 61 can engage with, for example, a bone fragment fractured and separated from the lateral portion 520 of the radius 500, thereby pulling the bone fragment closer and promoting the repair of the lateral portion 520 of the radius 500. In this embodiment, it is preferable, but not limited to, the plate 10 has two locking portions 56. Similarly, it is preferable, but not limited to, that the plate 10 has two second locking portions 61. When the claw-shaped locking portion 56 protrudes from the distal end 510 of the radius 500, it is preferable that the claw-shaped locking portion 56 protrudes by 3 mm or less in a plan view. Similarly, when the second locking portion 61 protrudes from the lateral portion 520, it is preferable that the second locking portion 61 protrudes by 3 mm or less in a plan view. This is because such a protrusion is considered not to interfere with the flexion and extension movement of the wrist. Furthermore, the plate 10 of this embodiment can also be applied to bones other than the radius 500. In that case, the claw-shaped locking portion 56 can lock onto the tip of the bone (not shown), while the second locking portion 61 can lock onto the side surface of the bone (not shown).

[0034] Next, the bolt 100 that engages with the aforementioned hole 70 will be described. The bolt 100 has a bolt head 110 with an engaging portion 115 into which a tool is inserted and engaged, and a bone thread portion 150 that penetrates into the bone and screws into it. The bolt 100 is preferably made of 64 titanium. Stainless steel is also preferred.

[0035] The bolt head 110 has a so-called barrel shape, and the barrel-shaped body portion has a threaded portion 120 that serves as the male screw. Here, the barrel shape is preferably one that resembles a spherical shape with the top and bottom cut off, and the outer shape of the bolt head 110, which corresponds to the barrel-shaped body portion, is preferably configured to resemble the shape of a part of a sphere. In Figure 12B, the bolt head 110' before the threaded portion is machined has a barrel shape. In this embodiment, the pitch of the threaded portion 120 is preferably 0.4 millimeters, similar to the thickness S1 of the first projection 81 and the first groove 91. However, it is not limited to this dimension, but the thickness S1 of the first projection 81 and the first groove 91, the thickness S2 of the second projection 82 and the second groove 92, and the thickness S3 of the third projection 83 and the third groove 93 are preferably the same as the pitch of the threaded portion 120.

[0036] Next, the method of using plate 10 will be described. Place plate 10 against the radius 500. Plate 10 in this embodiment is suitable for fractures of the distal end 510 of the radius 500, and is positioned to be placed against the distal end 510 of the radius 500. At that time, as described above, plate 10 is positioned with the recess 51 against the protrusion 511 of the radius 500, and the claw-shaped locking portion 56 engages with the distal end 510 of the radius 500. Also, the second locking portion 61 engages with the side portion 520 of the radius 500. In this embodiment, it is preferable that plate 10 has two claw-shaped locking portions 56 and two second locking portions 61. However, the number is not limited to these.

[0037] Thus, the plate 10 has either or both of the recess 51 and the claw-shaped locking portion 56, or the second locking portion 61, which allows for quick and easy positioning when applying it to the radius 500. Therefore, the plate 10 of this embodiment can be quickly and reliably applied to the distal end 510 of the radius 500.

[0038] Next, bolts 100 are inserted into each of the multiple holes 70 to fix the plate 10 to the radius 500. To do this, the bolts 100 need to be fixed to the radius 500 at various angles. For example, when the bolt 100 is upright relative to the hole 70, the threaded portion 120 of the bolt head 110 contacts one of the first projection 81, the second projection 82, the third projection 83, or the fourth projection 84. As the first projection 81, the second projection 82, the third projection 83, and the fourth projection 84 undergo plastic deformation due to the threaded portion 120, the first projection 81, the second projection 82, the third projection 83, and the fourth projection 84 engage with the threaded portion 120, fixing the bolt 100 to the hole 70 in the plate 10. However, the threaded portion 120 may undergo plastic deformation, causing the first projection 81, the second projection 82, the third projection 83, the fourth projection 84, and the threaded portion 120 to engage and fix the bolt 100 to the hole 70 in the plate 10. Furthermore, the threaded portion 120 and the first projection 81, the second projection 82, the third projection 83, and the fourth projection 84 may both deform and engage, fixing the bolt 100 to the hole 70 in the plate 10. Note that the opening 75 is omitted in Figure 15.

[0039] Furthermore, the bolt 100 is positioned at an angle to the hole 70. At this time, the head 110 of the bolt 100 has a barrel-shaped outer form, so the bolt 100 can be inserted into the hole 70 even when it is at an angle to the hole 70. In addition, the threaded portion 120 of the bolt head 110 contacts the first projection 81, the second projection 82, and the third projection 83, and as these projections are plastically deformed by the threaded portion 120, the first projection 81, the second projection 82, and the third projection 83 and the threaded portion 120 interlock, fixing the bolt 100 and the hole 70 in the plate 10 in an angled position. However, the threaded portion 120 may undergo plastic deformation, causing the first projection 81, the second projection 82, the third projection 83, the fourth projection 84, and the threaded portion 120 to engage and fix the bolt 100 to the hole 70 in the plate 10. Furthermore, the threaded portion 120 and the first projection 81, the second projection 82, the third projection 83, and the fourth projection 84 may both deform and engage, fixing the bolt 100 to the hole 70 in the plate 10. Note that the opening 75 is omitted in Figure 16.

[0040] Furthermore, when the bolt 100 is positioned at an angle to the hole 70, as described above, the head 110 of the bolt 100 has a barrel-shaped outer form, so it can be positioned at any angle to the hole 70 and fixed at that angle. Therefore, it is not limited to a certain angle. Also, when the plate 10 is made of pure titanium and the bolt 100 is made of 64 titanium, the second projection 82 and the third projection 83 in the hole 70 of the plate 10 are crushed, and the bolt 100 is fixed in place.

[0041] However, it is also preferable to make the plate 10 out of 64 titanium and the bolt 100 out of pure titanium, and it is also preferable to make the plate 10 and the bolt 100 out of pure titanium or 64 titanium, respectively. If there is a difference in hardness between the materials of the plate 10 and the bolt 100, one of them will be more easily deformed, allowing them to interlock and be fixed together. Even if both are made of the same material, they can still interlock and be fixed together. In this embodiment, the plate 10 has been described as being applicable to the radius 500, but it goes without saying that it is not limited to the radius 500 and can be applied to fractures of bones other than the radius. [Explanation of Symbols]

[0042] 10 plates 11 Surface 12 Back side 20 Main body 50 heads 51 Recess 56 Locking part 61 Second locking section 70 Hole 71 Inner self 81 1st protrusion 82 2nd protrusion 83 Third protrusion 84 4th protrusion 91 First groove 91a 1st side part 92 Second groove 92a 2nd side part 93 Third groove 93a 3rd side part 100 volts 110 bolt head 120 threaded section

Claims

1. It has a hole for inserting a bolt having a threaded portion, The aforementioned hole has a first projection positioned along the inner surface of the hole, When the bolt is inserted into the hole, the threaded portion comes into contact with the first projection. The first projection deforms to engage with the hole and the bolt, forming a plate.

2. It has a hole for inserting a bolt having a threaded portion, The aforementioned hole includes a first projection positioned along the inner surface of the hole, Below the first projection, there is a second projection positioned along the inner surface of the hole, When the bolt is inserted into the hole, the threaded portion comes into contact with the first projection and the second projection. The first projection and the second projection deform to engage with the hole and the bolt in a plate.

3. It has a hole for inserting a bolt having a threaded portion, The aforementioned hole includes a first projection positioned along the inner surface of the hole, Below the first projection, a second projection is positioned along the inner surface of the hole, A third projection is positioned below the second projection so as to follow the inner surface of the hole, It has, When the bolt is inserted into the hole, the threaded portion comes into contact with any of the first projection, the second projection, or the third projection. The plate is such that any of the first, second, or third projections that come into contact with the threaded portion deforms, thereby engaging the hole and the bolt.

4. It has a hole for inserting a bolt having a threaded portion, The aforementioned hole includes a first projection positioned along the inner surface of the hole, Below the first projection, a second projection is positioned along the inner surface of the hole, A third projection is positioned below the second projection so as to follow the inner surface of the hole, Below the third projection, a fourth projection is positioned along the inner surface of the hole, It has, The aforementioned threaded portion has a barrel shape, A first groove, which is groove-shaped, is formed between the first projection and the second projection. A second groove, which is groove-shaped, is formed between the second projection and the third projection. A third groove, which is groove-shaped, is formed between the third projection and the fourth projection. It has, The first groove portion has a first side surface portion which is a side surface, The second groove portion has a second side surface portion which is a side surface, The third groove portion has a third side surface portion which is a side surface, The first side portion, the second side portion, and the third side portion have an inverse tapered shape. When the bolt is inserted into the hole, any of the first, second, third, or fourth projections that come into contact with the threaded portion deform, thereby engaging the hole and the bolt in the plate.

5. It has a hole for inserting a bolt having a threaded portion, The aforementioned hole includes a first projection positioned along the inner surface of the hole, Below the first projection, a second projection is positioned along the inner surface of the hole, A third projection is positioned below the second projection so as to follow the inner surface of the hole, Below the third projection, a fourth projection is positioned along the inner surface of the hole, It has, The aforementioned threaded portion has a barrel shape, A first groove, which is groove-shaped, is formed between the first projection and the second projection. A second groove, which is groove-shaped, is formed between the second projection and the third projection. A third groove, which is groove-shaped, is formed between the third projection and the fourth projection. It has, The first groove portion has a first side surface portion which is a side surface, The second groove portion has a second side surface portion which is a side surface, The third groove portion has a third side surface portion which is a side surface, The first side portion, the second side portion, and the third side portion have an inverse tapered shape. When the bolt is inserted into the hole at an angle, any of the first, second, third, or fourth projections that come into contact with the threaded portion deform, thereby causing the hole and the bolt to engage with the plate.