Bone block fixation screw

Abstract

The present invention provides a bone block fixing screw, which comprises: a nail column, a nail cap and a traction rope; the nail cap is arranged at the top end of the nail column, and the side wall of the nail column is provided with an external thread; the bottom end of the nail column is provided with a through hole, and the traction rope is passed through the through hole; during surgery, the traction rope is passed through the second mounting hole on the scapula, and then the nail column is moved toward the second mounting hole by pulling the traction rope until the bottom end of the nail column abuts against the outside of the second mounting hole, and the nail column can be accurately passed into the second mounting hole, so that the installation of the bone block fixing screw is relatively simple, and the difficulty of surgery is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, and in particular to a bone block fixing screw. Background Art

[0002] Recurrent shoulder dislocation refers to the repeated dislocation of the shoulder due to accidental movements in the patient's daily life due to the failure to repair the damaged joint capsule and labrum in time after the initial trauma; therefore, how to treat recurrent shoulder dislocation has become a hot topic of research.

[0003] In the prior art, a portion of bone is often cut from the coracoid process of the patient, and then the bone is fixed to the scapula outside the labrum of the patient through a bone fixing screw. The bone can prevent the spherical articular cartilage from detaching from the labrum, thereby preventing the shoulder joint from dislocating. The bone fixing screw includes: a nail column and a nail cap; the side wall of the nail column is provided with an external thread, and the top cap is provided at the top of the nail column; during the operation, a portion of the bone is first cut from the coracoid process of the patient, and a first mounting hole is drilled on the bone block; then a second mounting hole is drilled on the scapula; then the bone block is fitted on the scapula, and the first mounting hole is directly opposite to the second mounting hole, then the front end of the guide tube is pressed against the bone block, and the guide tube is connected to the first mounting hole, and then the bone fixing screw is placed in the guide tube, so that the nail column is inserted into the first mounting hole, and then the nail column is twisted so that the nail column is gradually screwed into the second mounting hole under the action of the external thread, and then the bone block is fixed on the scapula to complete the operation.

[0004] However, in the prior art, when installing the bone block fixing screw, a guide tube is required to guide the screw so that the screw column is inserted into the first installation hole; after the front end of the guide tube abuts against the bone block, the front end of the guide tube is easy to move on the bone block, thereby causing the guide tube to be unable to face the first installation hole, making it difficult for the bone block fixing screw to be accurately inserted into the first installation hole, making the bone block fixing screw difficult to install and the operation difficult. Summary of the invention

[0005] In view of this, the present invention provides a bone block fixing screw to solve the technical problem that in the prior art, a guide tube is used to guide the screw. After the front end of the guide tube abuts against the bone block, the front end of the guide tube is easy to move on the bone block, resulting in difficulty in installing the bone block fixing screw and great difficulty in surgery.

[0006] The present invention provides a bone block fixing screw, comprising: a nail column, a nail cap and a traction rope; the nail cap is arranged at the top of the nail column, and the side wall of the nail column is provided with an external thread; the bottom end of the nail column is provided with a through hole, and the traction rope is passed through the through hole.

[0007] As described above, for the bone block fixing screw, preferably, a guide portion is provided at the bottom end of the screw column, and the through hole is provided on the guide portion.

[0008] As described above, for the bone block fixing screw, preferably, a guide cone is provided at the bottom end of the guide portion.

[0009] As for the bone block fixing screw as described above, preferably, a receiving groove is provided on the side wall of the guide portion, and the traction rope outside the through hole is received in the receiving groove.

[0010] As described above, the bone block fixing screw preferably comprises a first section and a second section, the top end of the first section is connected to the screw cap, and the top end of the second section is connected to the bottom end of the first section; the through hole is arranged at the bottom end of the second section; and the external thread is arranged on the side wall of the second section.

[0011] As described above, for the bone block fixing screw, preferably, the outer diameter of the external thread is larger than the diameter of the first section.

[0012] As mentioned above, for the bone block fixing screw, preferably, a driving part is provided on the screw cap.

[0013] As described above, in the bone block fixing screw, preferably, the driving portion comprises a cross slot provided at the top end of the screw cap.

[0014] As described above, for the bone block fixing screw, preferably, one end of the screw cap facing the screw post has a plane perpendicular to the axis of the screw post.

[0015] In the bone block fixing screw as described above, preferably, the traction rope is a nylon rope.

[0016] The bone block fixing screw provided by the present invention has a nail cap arranged on the top end of the nail column, an external thread arranged on the side wall of the nail column, and a through hole arranged at the bottom end of the nail column, and a traction rope is passed through the through hole. During surgery, the traction rope is passed through the second mounting hole on the scapula, and then the traction rope is pulled to move the nail column toward the second mounting hole until the bottom end of the nail column abuts against the outside of the second mounting hole, and the nail column can be accurately inserted into the second mounting hole. The installation of the bone block fixing screw is relatively simple, and the difficulty of surgery is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of a bone block fixing screw provided in an embodiment of the present invention;

[0019] Figure 2 A cross-sectional view of a bone block fixing screw provided in an embodiment of the present invention;

[0020] Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0021] Description of reference numerals:

[0022] 10. Nail cap;

[0023] 20. Nail pillar;

[0024] 30. Traction rope;

[0025] 40. Guide part;

[0026] 50. Guide cone;

[0027] 201, first paragraph;

[0028] 202, second paragraph;

[0029] 2021, External thread. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Figure 1 A schematic diagram of the structure of a bone block fixing screw provided in an embodiment of the present invention; Figure 2 A cross-sectional view of a bone block fixing screw provided in an embodiment of the present invention; Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0032] Please refer to Figure 1-Figure 3 The present embodiment provides a bone fixation screw, comprising: a screw post 20, a screw cap 10 and a traction rope 30; the screw cap 10 is arranged at the top of the screw post 20, and an external thread 2021 is arranged on the side wall of the screw post 20; a through hole is arranged at the bottom end of the screw post 20, and the traction rope 30 is passed through the through hole.

[0033] Specifically, the material of the nail post 20 in this embodiment can be various, for example, the nail post 20 can be made of stainless steel to prevent the nail post 20 from rusting in the body and affecting the patient's body; or, the nail post 20 can be mainly made of ceramic or plastic. It should be noted that the material constituting the nail post 20 needs to be non-toxic and harmless to prevent the toxic substances on the nail post 20 from entering the patient's tissue after the operation and affecting the patient's normal life.

[0034] In this embodiment, the nail column 20 is preferably a titanium alloy column. Titanium alloy is non-toxic, has a low density, high strength, and good affinity with the human body.

[0035] Titanium alloy is an alloy composed of titanium as the base element and other elements. Titanium alloy has good corrosion resistance and high specific strength. It is widely used in artificial organs, medical devices implanted in the human body, etc.

[0036] The nail cap 10 can be connected to the top of the nail column 20 by welding or bolting, or the nail cap 10 can be integrally formed with the nail column 20 by casting. The shape of the nail cap 10 in this embodiment can be various, for example: the nail cap 10 can be in a regular shape such as a circular plate, a hemispherical shape, or the nail cap 10 can be in other irregular shapes; as long as it is ensured that the nail cap 10 can be pressed against the bone block to prevent the nail cap 10 from entering the first mounting hole. Preferably, the contact area between the nail cap 10 and the bone block is increased as much as possible to reduce the pressure between the nail cap 10 and the bone block, so as to avoid the pressure between the nail cap 10 and the bone block being too high to crush the bone block at the edge of the first mounting hole.

[0037] Specifically, the external thread 2021 can be distributed on the side wall of the entire nail column 20, that is, the external thread 2021 is continuously arranged on the side wall of the nail column 20. At this time, it is necessary to ensure that the aperture of the first mounting hole is larger than the outer diameter of the external thread 2021, and at the same time, the aperture of the second mounting hole is smaller than the outer diameter of the external thread 2021; in this way, when the nail column 20 is screwed into the second mounting hole, the external thread 2021 in the first mounting hole will not drive the bone block to move; at the same time, the external thread 2021 will tap out an internal thread that cooperates with the external thread 2021 on the side wall of the second mounting hole on the scapula. With the cooperation of the internal and external threads 2021, the bone block is pressed against the scapula to achieve fixation of the bone block.

[0038] Preferably, the tooth profile of the external thread 2021 in this embodiment can be a triangle, and of course the tooth profile of the external thread 2021 can also be a rectangle or a trapezoid. The thread lead angle of the external thread 2021 is reasonably set so that the thread lead angle is smaller than the equivalent friction angle of the spiral pair formed by the shoulder blade and the external thread 2021, so that the external thread 2021 has a self-locking function to prevent the external thread 2021 from loosening in the second mounting hole after installation, and then gradually withdrawing from the second mounting hole.

[0039] It should be noted that the length of the nail column 20 needs to be greater than the thickness of the bone block. After the nail column 20 is inserted into the first mounting hole, the bottom end of the nail column 20 passes through the first mounting hole and is located outside the bone block so that the nail column 20 can be screwed into the second mounting hole.

[0040] Specifically, in this embodiment, the through hole can be set on the side wall of the nail column 20 near the bottom end, the center line of the through hole is perpendicular to the axis of the nail column 20, and the through hole runs through the entire nail column 20. Alternatively, a through hole is opened inward at the bottom end of the nail column 20, and an opening is formed at the bottom end of the nail column 20 accordingly. In this case, the center line of the through hole is a curve, so that the other opening of the through hole is formed on the side wall of the nail column 20, and the traction rope 30 passes through the through hole through the opening at the bottom end and passes out from the other opening on the side wall of the nail column 20; or the center line of the through hole is semicircular, and in this case, both openings of the through hole are located at the bottom end of the nail column 20.

[0041] The traction rope 30 in this embodiment can be of various types, as long as it can pull the nail column 20 and the bone block to move; for example: the traction rope 30 can be a steel wire rope, and the strength of the steel wire rope is relatively high to prevent the traction rope 30 from breaking due to excessive pulling force when the traction rope 30 is pulled; in addition, the hardness of the steel wire rope is relatively high, which can prevent the traction rope 30 from rubbing against the side walls of the first mounting hole and the second mounting hole when the traction rope 30 is pulled, thereby preventing the traction rope 30 from breaking.

[0042] In this embodiment, the traction rope 30 is preferably a nylon rope. The hardness of the nylon rope is relatively small, and it is easy to bend. In other embodiments, the traction rope 30 can also be a hemp rope, etc.

[0043] The installation process of the bone block fixing screw provided in this embodiment is as follows: first, a bone block is cut from the patient's coracoid process, and then a first installation hole is opened on the bone block; the screw column 20 is inserted into the first installation hole, and then the traction rope 30 is inserted into the through hole on the screw column 20; then a second installation hole is drilled on the scapula, and the second installation hole passes through the entire scapula. A guide needle with a diameter smaller than that of the second installation hole is used to pass both ends of the traction rope 30 through the second installation hole, so that both ends of the traction rope 30 enter from one end of the second installation hole, pass through the second installation hole, and stay on the outside of the other end, and then the guide needle is removed; then the traction rope is pulled out The two ends of 30 are connected so that the traction rope 30 drives the nail column 20 and the bone block to move toward the scapula; because the traction rope 30 is inserted into the through hole at the bottom end of the nail column 20, when the nail column 20 moves, the bottom end of the nail column 20 is closer to the scapula than the top end of the nail column 20; when the traction rope 30 is pulled to the limit, the bottom end of the nail column 20 just hits the opening of the second mounting hole; then the nail column 20 is twisted to make the nail column 20 gradually screwed into the second mounting hole, and at the same time, the external thread 2021 on the nail column 20 taps out the internal thread matching it on the side wall of the second mounting hole until the bone block hits the scapula to complete the installation of the bone block fixing screw.

[0044] The bone block fixing screw provided in this embodiment is provided with a nail cap 10 at the top end of the nail column 20, and an external thread 2021 is provided on the side wall of the nail column 20; and a through hole is provided at the bottom end of the nail column 20, and a traction rope 30 is passed through the through hole; during surgery, the traction rope 30 is passed through the second mounting hole on the scapula, and then the traction rope 30 is pulled to move the nail column 20 toward the second mounting hole until the bottom end of the nail column 20 abuts against the outside of the second mounting hole, and the nail column 20 can be accurately inserted into the second mounting hole, and the installation of the bone block fixing screw is relatively simple, which reduces the difficulty of surgery.

[0045] Continue to refer to Figure 1 and Figure 2 Specifically, a guide portion 40 is provided at the bottom end of the nail column 20, and a through hole is provided on the guide portion 40. Pulling the traction rope 30 can make the guide portion 40 penetrate into the second mounting hole first, and then twist the nail column 20 to screw the nail column 20 into the second mounting hole, so as to avoid the bottom end of the nail column 20 being difficult to align with the second mounting hole when twisting the nail column 20.

[0046] Preferably, the guide portion 40 in this embodiment can have a variety of shapes, for example, the guide portion 40 can be cylindrical, the center line of the guide portion 40 is arranged colinearly with the axis of the nail column 20, and the diameter of the guide portion 40 should be smaller than the aperture of the second mounting hole, so that when the guide portion 40 is pulled by the traction rope 30, the guide portion 40 can drive the nail column 20 and the bone block to move toward the scapula, and the guide portion 40 can be directly inserted into the second mounting hole; correspondingly, a through hole is opened from the side wall of the guide portion 40 to the inside, and the two openings of the through hole are both located on the side wall of the guide portion 40, and the center line of the through hole is a straight line, and the center line is perpendicular to the center line of the guide portion 40; the through hole is as close as possible to the end of the guide portion 40 away from the nail column 20. Of course, the guide portion 40 can also be hemispherical, in which case the bottom surface of the guide portion 40 is connected to the nail column 20.

[0047] Preferably, the guide portion 40 can be connected to the nail column 20 by welding, or the guide portion 40 can be integrally formed with the nail column 20 by casting.

[0048] Continue to refer to Figure 1 and Figure 2 Specifically, a guide cone 50 is provided at the bottom end of the guide portion 40. The guide cone 50 can guide the guide portion 40. When the conical surface of the guide cone 50 contacts the side wall of the second mounting hole, the guide cone 50 can enter the second mounting hole along the conical surface by pulling the traction rope 30, so as to prevent the bottom end of the guide portion 40 from abutting against the shoulder blade at the edge of the second mounting hole, thereby preventing the guide portion 40 from entering the second mounting hole.

[0049] In this embodiment, the guide cone 50 is preferably in a cone shape, the bottom surface of the cone is connected to the bottom end of the guide portion 40 away from the nail column 20, and the center line of the guide cone 50 is arranged colinearly with the axis of the nail column 20.

[0050] In other embodiments, the guide cone 50 may be in a pyramidal shape, such as a triangular pyramid, a quadrangular pyramid, etc. It should be noted that when the guide cone 50 is in a pyramidal shape, rounded corners need to be provided on the side edges of the pyramid to prevent the side edges from scratching the patient's tissue when the pyramid moves.

[0051] Preferably, in this embodiment, the guide cone 50 and the guide portion 40 can be connected by welding, or the guide cone 50 can be integrally formed with the guide portion 40 by casting.

[0052] The installation process of the bone block fixing screw provided in this embodiment is as follows: first, a bone block is cut from the patient's coracoid process, and then a first installation hole is opened on the bone block; the nail column 20 is inserted into the first installation hole, and then the traction rope 30 is inserted into the through hole on the nail column 20; then, a second installation hole is drilled on the scapula, and the second installation hole passes through the entire scapula. A guide needle with a diameter smaller than that of the second installation hole is used to pass both ends of the traction rope 30 through the second installation hole, so that the two ends of the traction rope 30 enter from one end of the second installation hole, pass through the second installation hole, and stay on the outside of the other end, and then remove the guide needle; then, the two ends of the traction rope 30 are pulled, so that the traction rope 30 drives the guide part 40, the guide cone 50, the nail column 20 and the bone The block moves toward the scapula; since the traction rope 30 is inserted into the through hole on the guide part 40 at the bottom end of the nail column 20, when the nail column 20 moves, the guide cone 50 is closer to the scapula than the top of the nail column 20 and the bone block; the guide cone 50 first enters the second mounting hole, and then under the guiding action of the guide cone 50, the guide part 40 enters the second mounting hole; when the traction rope 30 is pulled to the limit, the bottom end of the nail column 20 just abuts against the opening of the second mounting hole; then the nail column 20 is twisted to make the nail column 20 gradually screwed into the second mounting hole, and at the same time, the external thread 2021 on the nail column 20 taps out the internal thread matching it on the side wall of the second mounting hole until the bone block abuts against the scapula to complete the installation of the bone block fixing screw.

[0053] Continue to refer to Figure 1 and Figure 2 Specifically, a receiving groove is provided on the side wall of the guide portion 40, and the traction rope 30 outside the through hole is received in the receiving groove. This prevents the traction rope 30 in contact with the guide portion 40 from protruding outward from the guide portion 40 when the traction rope 30 is pulled out, causing friction between the traction rope 30 and the side wall of the second mounting hole, thereby preventing the traction rope 30 from breaking.

[0054] Specifically, there are two receiving grooves, which are respectively arranged on the guide parts 40 outside the two openings of the through hole, so that the traction ropes 30 extending from the two ends of the through hole are all accommodated in the receiving grooves.

[0055] Continue to refer to Figure 1-Figure 3 In this embodiment, the nail column 20 preferably includes a first section 201 and a second section 202. The top of the first section 201 is connected to the nail cap 10, and the top of the second section 202 is connected to the bottom of the first section 201. The through hole is provided at the bottom of the second section 202. The external thread 2021 is provided on the side wall of the second section 202. The first section 201 that matches the first mounting hole is not provided with the external thread 2021, so as to avoid the bone block from moving when the nail column 20 is rotated, resulting in insufficient bone block installation accuracy.

[0056] It should be noted that, at this time, the apertures of the first mounting hole and the second mounting hole can be the same, that is, the apertures of the first mounting hole and the second mounting hole are both smaller than the outer diameter of the external thread 2021; so that the first mounting hole and the second mounting hole can be formed by the same bone drill, reducing the number of surgical tools. During the operation, the bone block can be cut from the patient's coracoid process first, and then the first mounting hole is drilled on the coracoid process by the bone drill, and then the second section 202 is screwed into the first mounting hole, and until the second section 202 completely passes through the first mounting hole, at this time the first section 201 is in the first mounting hole; because the second section 202 will tap out the internal thread in the first mounting hole when passing through the first mounting hole, when the bone block fixing screw and the bone block move, the internal thread and the external thread 2021 cooperate to prevent the bone block and the nail column 20 from detaching.

[0057] Continue to refer to Figure 2 and Figure 3 Preferably, the outer diameter of the external thread 2021 is greater than the diameter of the first section 201. Increasing the outer diameter of the external thread 2021 can enhance the connection strength between the external thread 2021 and the scapula to prevent the nail column 20 from falling out of the second mounting hole after surgery.

[0058] Specifically, a driving part is provided on the nail cap 10. By driving the driving part on the nail cap 10, the nail column 20 is driven to rotate, and the nail column 20 is screwed into the second mounting hole, which is easy to operate.

[0059] Preferably, there can be multiple types of driving parts, for example: the driving part can be a driving groove with a hexagonal cross-section formed on the nail cap 10, and a hexagonal driving column can be inserted into the driving groove during installation, and then the nail cap 10 is twisted by driving the driving column to drive the nail column 20 to rotate; or the driving part can be a clamping column with a hexagonal cross-section arranged on the nail cap 10, and a wrench matching the clamping column can be used to drive the clamping column to rotate during installation, thereby driving the nail column 20 to rotate.

[0060] In this embodiment, the driving part preferably includes a cross slot that is recessed inwardly at the top of the nail cap 10. The bone block fixing screw is installed by a cross screwdriver that cooperates with the cross slot, and the cross slot is not easily damaged by the cross screwdriver.

[0061] The installation process of the bone fixation screw provided in the present embodiment is as follows: first, a bone block is cut from the coracoid process of the patient, and then a first installation hole is opened on the bone block; the nail column 20 is inserted into the first installation hole, and then the traction rope 30 is inserted into the through hole on the nail column 20; then, a second installation hole is drilled on the scapula, and the second installation hole passes through the entire scapula. A guide needle with a diameter smaller than that of the second installation hole is used to pass both ends of the traction rope 30 through the second installation hole, so that the two ends of the traction rope 30 enter from one end of the second installation hole, pass through the second installation hole, and stay on the outside of the other end, and then remove the guide needle; then, the two ends of the traction rope 30 are pulled, so that the traction rope 30 drives the guide part 40, the guide cone 50, the nail column 20 and the bone block to move toward the scapula; because the traction rope 30 is inserted into the through hole on the guide part 40, when the nail column 20 moves , the guide cone 50 is closer to the scapula than the top of the nail column 20 and the bone block; the guide cone 50 first enters the second mounting hole, and then under the guiding action of the guide cone 50, the guide part 40 enters the second mounting hole; in the process of pulling the plate traction rope 30, the traction rope 30 is tensioned after being subjected to tension, so that the traction rope 30 located on the side wall of the guide part 40 is accommodated in the accommodating groove; when the traction rope 30 is pulled to the limit, the bottom end of the nail column 20 just hits the opening of the second mounting hole; then the cross screwdriver is matched with the cross slot on the nail cap 10, and then the nail column 20 is twisted by the cross screwdriver, so that the nail column 20 is gradually screwed into the second mounting hole. At the same time, the external thread 2021 on the nail column 20 taps out the internal thread matching it on the side wall of the second mounting hole until the bone block hits the scapula to complete the installation of the bone block fixing screw.

[0062] In this embodiment, the end of the nail cap 10 facing the nail post 20 has a plane perpendicular to the axis of the nail post 20. When in use, the plane fits the bone block, which can avoid damage to the bone block caused by the contact between the nail cap 10 and the bone block.

[0063] In the present invention, unless otherwise clearly defined, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral molding, it can be a mechanical connection, it can be an electrical connection, or it can communicate with each other; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bone block fixing screw, characterized in that: include: A nail column, a nail cap and a traction rope; the nail cap is arranged on the top of the nail column, and the side wall of the nail column is provided with an external thread; a through hole is arranged on the side wall of the bottom end of the nail column, and the traction rope is passed through the through hole.

2. The bone block fixing screw according to claim 1, characterized in that: A guide portion is provided at the bottom end of the nail column, and the through hole is provided on the guide portion.

3. The bone block fixing screw according to claim 2, characterized in that: A guide cone is arranged at the bottom end of the guide portion.

4. The bone block fixing screw according to claim 2, characterized in that: A receiving groove is provided on the side wall of the guide portion, and the traction rope outside the through hole is received in the receiving groove.

5. The bone block fixing screw according to any one of claims 1 to 4, characterized in that: The nail column includes a first section and a second section, the top of the first section is connected to the nail cap, and the top of the second section is connected to the bottom of the first section; the through hole is arranged at the bottom of the second section; and the external thread is arranged on the side wall of the second section.

6. The bone block fixing screw according to claim 5, characterized in that: The outer diameter of the external thread is greater than the diameter of the first section.

7. The bone block fixing screw according to any one of claims 1 to 4, characterized in that: The nail cap is provided with a driving part.

8. The bone block fixing screw according to claim 7, characterized in that: The driving part includes a cross groove arranged on the top end of the nail cap.

9. The bone block fixing screw according to any one of claims 1 to 4, characterized in that: One end of the nail cap facing the nail column has a plane perpendicular to the axis of the nail column.

10. The bone block fixing screw according to any one of claims 1 to 4, characterized in that: The traction rope is a nylon rope.

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