Bone taking knife with adjustable blade angle

Abstract

The utility model relates to a bone taking knife with an adjustable cutting edge angle, which belongs to the field of medical instruments in the department of stomatology and comprises a handle part, a rod part and a cutting edge part, the handle part and the rod part are integrally formed, the cutting edge part is arranged at the tail end of the rod part, and the tail end of the rod part is detachably connected with the cutting edge part; the edge part comprises a blade, the side surface of the blade is arc-shaped, and the tail end of the blade is a cut-off surface to form a cutting edge; the projection of the cut-off surface of the tail end of the blade on the longitudinal section of the center line of the rod passing part is a straight line perpendicular to the center line of the rod passing part or an oblique line not perpendicular to the center line of the rod passing part. According to the bone taking knife with the adjustable blade angle, massive bones can be taken out conveniently, the operation time of an operation is greatly shortened, and the bone taking knife is a special taking-out instrument for the massive bones.

Description

Technical Field

[0001] The utility model belongs to the field of stomatology medical instruments, and in particular relates to a bone removal knife with adjustable blade angle. Background Art

[0002] In oral implants, large bone defects require autologous block bone transplantation. Most doctors often use instruments such as bone chisels or tooth extraction spuds to pry and then remove the block bone.

[0003] Existing instruments for removing block bones are dental elevators and osteotome. Among them, the tip of the dental elevator is designed to be curved to fit the tooth root, which has low bone cutting efficiency and is not suitable for straight cutting of block bones. Although the tip of the osteotome is designed to be straight, the blade angle cannot be adjusted and can only be inserted into the superficial part of the block bone cutting line or limited to the cortical bone. The prying depth is shallow, which leads to a reduction in the volume of block bone that can be removed.

[0004] Since the bone around the bone defect in the oral cavity is relatively loose, the cancellous bone has fast blood supply reconstruction and contains a large number of bone marrow stem cells and growth factors related to osteogenesis, the reduction of cancellous bone will seriously affect the bone reconstruction effect. This requires that during the block bone transplantation, the bone cutting efficiency should be high, the prying depth should be deeper, and a larger block bone volume can be cut. Therefore, for the block bone transplantation of oral implant bone defects, there is currently a lack of a special block bone removal instrument with high bone cutting efficiency, deeper prying depth, and the ability to cut a larger block bone volume. Summary of the invention

[0005] In view of the above problems, the purpose of the utility model is to provide a bone removal knife with an adjustable blade angle, which is used to solve the current problem of lack of a special block bone removal instrument with high bone cutting efficiency, deeper prying depth, and the ability to cut larger block bones.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] The utility model discloses a bone removal knife with adjustable blade angle, comprising a handle portion, a rod portion and a blade portion, wherein the handle portion and the rod portion are integrally formed, the blade portion is arranged at the end of the rod portion, and the end of the rod portion is detachably connected to the blade portion;

[0008] The blade portion includes a blade, the side surface of the blade is in an arc shape, and the end of the blade forms a cutting edge for the cutting surface;

[0009] The projection of the cut surface of the end of the blade on the longitudinal section passing through the center line of the rod portion is a straight line perpendicular to the center line of the rod portion or a non-perpendicular oblique line.

[0010] Specifically, the length of the blade is less than 1 cm; the length of the projection of the cut surface of the blade end on the longitudinal section passing through the center line of the rod portion is 3 to 5 mm.

[0011] Preferably, the bone removal knife with adjustable blade angle comprises at least one blade set, the blade set comprises a plurality of blades, and the angle γ between the projection of the cut surface of the blade end of the blade on the longitudinal section passing through the center line of the rod and the cross section of the rod satisfies: 0≤γ≤40°.

[0012] Preferably, when the projection of the cut surface of the end of the blade on the longitudinal section passing through the center line of the rod is a straight line perpendicular to the center line of the rod, the angle γ between the projection of the cut surface of the end of the blade of the cutting edge on the longitudinal section passing through the center line of the rod and the cross section of the rod is 0°;

[0013] When the projection of the cut surface of the end of the blade on the longitudinal section passing through the center line of the rod is an oblique line that is not perpendicular to the center line of the rod, the angle γ between the projection of the cut surface of the end of the blade of the cutting edge on the longitudinal section passing through the center line of the rod and the cross section of the rod is 15°, 20°, 30° or 40°.

[0014] Preferably, a joint is provided at the end of the rod portion, and a hexagonal nut hole is provided in the joint; the blade portion also includes a hexagonal nut and a transition section, the transition section is narrow at the bottom and wide at the top, and the hexagonal nut is connected to the blade through the transition section; the hexagonal nut of the blade portion is inserted and embedded in the hexagonal nut hole of the joint of the rod portion.

[0015] Preferably, the wall of the joint extends outward to form an outer flange, and the outer wall of the outer flange is provided with an external thread; the outer flange is configured with an end cover, the center of the end cover is provided with a blade through hole, the edge of the end cover is provided with a cover wall, and the cover wall is provided with an internal thread; the blade through hole of the end cover passes through the blade and the transition section of the blade from bottom to top in sequence, and is connected to the outer flange of the joint by a thread.

[0016] Preferably, the hexagonal nut, the transition section and the blade are integrally formed.

[0017] Preferably, the diameter of the hole of the blade portion of the end cover is larger than the maximum outer diameter of the transition section of the blade portion, but smaller than the outer diameter of the circumscribed circle of the hexagonal nut of the blade portion.

[0018] Preferably, the outer diameter of the outer flange is smaller than the outer diameter of the outer wall of the joint, and the outer diameter of the outer wall of the joint is equal to the outer diameter of the cover wall of the end cover.

[0019] Preferably, the total length of the bone removal knife with adjustable blade angle does not exceed 20 cm.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] (i) Compared with the tooth elevator in the prior art, in which the end of the blade is designed to be an arc suitable for the tooth root, the bone removal knife with an adjustable blade angle disclosed in the utility model sets the end of the blade of the blade as a cutting surface and forms a blade, and the projection of the cutting surface of the end of the blade on the longitudinal section passing through the center line of the rod is a straight line perpendicular to the center line of the rod, so as to obtain a larger cutting line, which can be inserted into the bottom of the block bone cutting line, not only increasing the prying force, but also increasing the hardness of the block bone elevator, which can significantly improve the bone cutting efficiency.

[0022] (ii) Compared with the bone chisel in the prior art, which has a straight tip but cannot adjust the blade angle, the bone removal knife with adjustable blade angle disclosed in the utility model is designed with blades of different angles according to the projection of the cut surface of the end of the blade on the longitudinal section passing through the center line of the rod as an oblique line not perpendicular to the center line of the rod, wherein the bone removal knife with adjustable blade angle includes at least one blade set, the blade set includes a plurality of blades, and the angle γ between the projection of the cut surface of the end of the blade of the blade on the longitudinal section passing through the center line of the rod and the cross section of the rod satisfies: 0≤γ≤40°. If the blade of the blade is designed to be oblique at 15°, 20°, 30° or 40°, it is convenient for doctors to select the appropriate cut surface of the end of the blade according to the size of the block bone to be removed from the patient to carry out surgery, such as the removal of block bones in different parts such as the ascending ramus of the mandible, the mandibular molar area, and the chin. The end of the rod is detachably connected to the blade. The doctor can select a suitable cutting surface at the end of the blade from the projections of the cutting surfaces at the end of the numerous blades on the longitudinal section passing through the center line of the rod and the angles at the center line of the rod to perform surgery, thereby achieving "adjustable blade angle". It can penetrate the superficial part of the block bone cutting line or the cortical bone, and can even be directly inserted to the depth reached by the ultrasonic bone knife. Prying can be performed to a deeper depth according to the cutting surface projected as an oblique line. The prying force can directly reach the base of the block bone, which is not only more suitable for cutting the block bone along the cutting line, but also the volume of the block bone removed can reach the maximum at this time, and ultimately a larger volume of cortical and cancellous bone can be pried and removed.

[0023] (III) The utility model discloses a bone removal knife with an adjustable blade angle, which not only retains the powerful prying force of the dental elevator, but also can pry to a deeper depth according to the cut surface projected as an oblique line, greatly increasing the volume of block bone removed. The utility model discloses a bone removal knife with an adjustable blade angle, which will greatly facilitate the removal of block bones and greatly shorten the operation time. It is a special removal instrument for block bones.

[0024] (IV) The utility model discloses a bone removal knife with an adjustable blade angle. The handle is designed to be cylindrical for easy holding. When necessary, it can be gently tapped to facilitate the blade of the bone removal knife to penetrate into the deepest part reached by the ultrasonic bone removal knife. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those skilled in the art. The accompanying drawings are only for the purpose of illustrating the preferred embodiment and are not to be considered as limiting the present invention.

[0026] Figure 1 This is a schematic diagram of the overall structure of a bone removal knife with adjustable blade angle provided in Example 1 of the utility model;

[0027] Figure 2 yes Figure 1 A partial enlarged view of the middle A;

[0028] Figure 3 This is an exploded view of the parts of a bone removal knife with adjustable blade angle provided in Example 1 of the utility model;

[0029] Figure 4 yes Figure 3 A partial enlarged view of point B in the middle;

[0030] Figure 5 It is a three-dimensional view of the joint at the end of the rod provided by Example 1 of the utility model from a top view, wherein the outer flange is perspectively processed in order to see the hexagonal nut hole;

[0031] Figure 6 It is a top view of the joint at the end of the rod provided in Example 1 of the utility model;

[0032] Figure 7 It is a schematic structural diagram of the blade provided by Example 1 of the present invention when the angle γ between the projection of the cut surface of the end of the blade of the blade on the longitudinal section passing through the center line of the rod portion and the cross section of the rod portion is 0°, wherein the cut surface of the end of the blade is perpendicular to the center line of the rod portion;

[0033] Figure 8 1 is a schematic diagram of the structure of the blade provided by Example 1 of the present invention when the angle γ between the projection of the cut surface of the end of the blade of the blade of the blade on the longitudinal section passing through the center line of the stem and the cross section of the stem is 15°, 20°, 30° and 40°, wherein Figure 8 (a) is γ = 15°, Figure 8 (b) is γ = 20°, Figure 8 (c) is γ = 30°, Figure 8 In (d), γ=40°.

[0034] Description of reference numerals: 1-handle portion;

[0035] 2-rod, 20-joint, 200-hexagonal nut hole, 21-external flange, 22-end cover;

[0036] 3-blade, 30-hexagonal nut, 31-blade, 32-transition section. DETAILED DESCRIPTION

[0037] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0038] In order to solve the problem that there is currently a lack of a special bone removal instrument for block bones with high bone cutting efficiency, deeper prying depth, and the ability to cut larger block bones, the utility model discloses a bone removal knife with an adjustable blade angle. First, the end of the blade of the blade is set as a cutting surface and forms a blade, and the projection of the cutting surface of the end of the blade on the longitudinal section passing through the center line of the rod is a straight line perpendicular to the center line of the rod, so as to obtain a larger cutting line, which can be inserted into the bottom of the block bone cutting line, which not only increases the prying force, but also increases the hardness of the block bone, and can significantly improve the bone cutting efficiency; secondly, according to the projection of the cutting surface of the end of the blade on the longitudinal section passing through the center line of the rod, the cutting surface of the end of the blade is adjusted to the cutting surface of the end of the blade. The image is designed with blades of different angles for the oblique lines that are not perpendicular to the center line of the shaft, such as designing the blade to be straight, oblique 15°, oblique 20°, oblique 30° or oblique 40°, which is convenient for doctors to choose. The end of the shaft is detachably connected to the blade. The doctor can, according to needs, select a suitable cutting surface of the blade end from the projections of the cutting surfaces of the blade ends on the longitudinal section passing through the center line of the shaft and the angles on the center line of the shaft to carry out surgery, thereby realizing the adjustment of the "adjustable blade angle", which can pass through the superficial part of the block bone cutting line or cortical bone, and can even be directly inserted to the depth reached by the ultrasonic bone knife, which will greatly facilitate the removal of the block bone.

[0039] Embodiment 1: A bone removal knife with adjustable blade angle

[0040] Embodiment 1 of the present invention provides a bone removal knife with adjustable blade angle, and its structure is described in detail below in conjunction with the accompanying drawings.

[0041] refer to Figures 1 to 4 The bone removal knife with adjustable blade angle comprises a handle portion 1, a rod portion 2 and a blade portion 3. The handle portion 1 and the blade portion 3 are connected together through the rod portion 2, and the handle portion 1 and the rod portion 2 are integrally formed.

[0042] The blade portion 3 is disposed at the end of the rod portion 2 , and the end of the rod portion 2 is detachably connected to the blade portion 3 .

[0043] The blade portion 3 includes a blade 31 , the side surface of the blade 31 is in an arc shape, and the end of the blade 31 forms a cutting edge for the cutting surface.

[0044] The projection of the cut surface at the end of the blade 31 on the longitudinal section passing through the center line of the rod portion 2 is a straight line perpendicular to the center line of the rod portion 2 or a non-perpendicular oblique line.

[0045] It should be noted that when the rod 2 is kept in a plumb state, when the projection of the cut surface of the end of the blade 31 on the longitudinal section passing through the center line of the rod 2 is perpendicular to the center line of the rod 2, the obtained projection is a straight line perpendicular to the center line of the rod 2, such as Figure 1 and Figure 2 When the obtained projection is not perpendicular to the center line of the rod 2, it is a slant line.

[0046] In order to facilitate insertion into the human mouth and be suitable for stomatology, the length of the arc-shaped piece is less than 1 cm, and the length of the projection of the cut surface at the end of the blade 31 on the longitudinal section passing through the center line of the rod part 2 is 3 to 5 mm.

[0047] Compared with the prior art, in which the end of the blade is designed to be an arc suitable for the root of the tooth, the end of the blade 31 of the embodiment 1 of the utility model changes this arc into a cutting surface, and the cutting surface is projected as a straight line or an oblique line perpendicular to the center line of the rod 2 on the longitudinal section, and the length of the straight line or the oblique line is 3 to 5 mm. Using the bone removal knife with adjustable blade angle of the utility model, not only can it be inserted into the superficial part or cortical bone of the block bone cutting line, but it can also be pried to a deeper depth according to the cutting surface projected as an oblique line, which greatly increases the removal of the block bone volume.

[0048] In order to facilitate the doctor to select a suitable cutting surface at the end of the blade 31 according to the size of the bone block to be removed from the patient to perform surgery, the bone removal knife with adjustable blade angle includes at least one blade set, the blade set includes a plurality of blades 3, and the angle γ between the projection of the cutting surface at the end of the blade 31 of the blade 3 on the longitudinal section passing through the center line of the rod 2 and the cross-section of the rod 2 satisfies: 0≤γ≤40°.

[0049] Specifically, when the projection of the cut surface of the end of the blade 31 on the longitudinal section passing through the center line of the rod 2 is a straight line perpendicular to the center line of the rod 2, the angle γ between the projection of the cut surface of the end of the blade 31 of the cutting edge 3 on the longitudinal section passing through the center line of the rod 2 and the cross section of the rod 2 is 0°, that is, a straight type, such as Figure 1 shown.

[0050] When the projection of the cut surface of the end of the blade 31 on the longitudinal section passing through the center line of the rod 2 is an oblique line that is not perpendicular to the center line of the rod 2, the angle γ between the projection of the cut surface of the end of the blade 31 of the cutting edge 3 on the longitudinal section passing through the center line of the rod 2 and the cross section of the rod 2 is 15°, 20°, 30° or 40°, that is, an oblique line of 15°, 20°, 30° or 40° is formed, such as Figure 8 shown.

[0051] The term "blade angle is adjustable" in the present invention means that the angle between the projection of the cut surface at the end of the blade 31 on the longitudinal section passing through the center line of the rod 2 and the projection of the cut surface on the center line of the rod 2 can be selected as needed to achieve adjustment.

[0052] As a specific method for realizing the detachable connection between the end of the rod 2 and the blade 3, the detachable connection between the end of the rod 2 and the blade 3 includes plug-in and threaded connection. The method of the detachable connection between the end of the rod 2 and the blade 3 is introduced in detail below.

[0053] First, regarding the connection between the end of the rod 2 and the blade 3: a joint 20 is provided at the end of the rod 2, and a hexagonal nut hole 200 is provided in the joint 20. Figure 5 and Figure 6 The blade 3 also includes a hexagonal nut 30 and a transition section 32, the shape of the transition section 32 is narrow at the bottom and wide at the top, the hexagonal nut 30 is connected to the blade 31 through the transition section 32, such as Figure 7 As shown; the hexagonal nut 30 of the blade 3 is inserted and embedded in the hexagonal nut hole 200 of the joint 20 of the rod 2, thereby achieving the plug-in connection between the end of the rod 2 and the blade 3.

[0054] Secondly, on the basis of plug-in connection, the detachable connection between the end of the rod part 2 and the blade part 3 also includes a threaded connection: the wall of the joint 20 extends outward to form an outer flange 21, and the outer wall of the outer flange 21 is provided with an external thread; the outer flange 21 is provided with an end cover 22, and a blade through hole is provided in the center of the end cover 22, and a cover wall is provided at the edge of the end cover 22, and an internal thread is provided on the cover wall; the blade through hole of the end cover 22 passes through the blade 31 and the transition section 32 of the blade 3 from bottom to top in sequence, and is connected to the outer flange 21 of the joint 20 by threads.

[0055] Therefore, on the basis of plug-in connection, a threaded connection is added between the end of the rod portion 2 and the blade portion 3 to achieve a detachable connection between the two.

[0056] Preferably, the hexagonal nut 30, the transition section 32 and the blade 31 are integrally formed.

[0057] In order to prevent the hexagonal nut 30 of the blade 3 from slipping out of the blade through hole of the end cover 22 when the blade 31 and the transition section 32 of the blade 3 are passed through from bottom to top in sequence, the hole diameter of the blade through hole of the end cover 22 is larger than the maximum outer diameter of the transition section 32 of the blade 3, but smaller than the outer diameter of the circumscribed circle of the hexagonal nut 30 of the blade 3.

[0058] In order to ensure that the outer wall of the end cover 22 can be tightly closed with the outer wall of the joint 20, the outer diameter of the outer flange 21 is smaller than the outer diameter of the outer wall of the joint 20, and the outer diameter of the outer wall of the joint 20 is equal to the outer diameter of the cover wall of the end cover 22.

[0059] In order to facilitate the doctor to hold the bone removal knife with adjustable blade angle, the rear end of the handle part 1 is thick and cylindrical, and a plurality of anti-slip ribs are arranged at the rear end of the handle part 1. More specifically, the front end of the handle part 1 gradually becomes smaller from the back to the front and is in a truncated cone shape.

[0060] It should be noted that the "rear end" here refers to the end pointing to the doctor when the doctor holds the handle part 1; the "end", also known as the "front end", is opposite to the "rear end", and refers to the end pointing to the patient when the doctor holds the handle part 1.

[0061] In order to facilitate the doctor to control the process of removing the block bone, the total length of the bone removal knife with adjustable blade angle shall not exceed 20 cm. Preferably, the total length of the bone removal knife with adjustable blade angle can be distributed in a stepped manner, such as 20 cm, 18 cm, 15 cm, 12 cm, 10 cm and 8 cm.

[0062] Embodiment 2: Method for using a bone removal knife with adjustable blade angle

[0063] Embodiment 2 of the present invention provides a method for using a bone removal knife with an adjustable blade angle, using the bone removal knife with an adjustable blade angle of embodiment 1, and the method for using the bone removal knife comprises the following steps:

[0064] Step 1: Hold the handle 1 and move the blade 3 to the position of the bone to be removed;

[0065] Step 2: Select the cutting surface of the end of the blade 31 according to the size of the bone block to be removed from the patient, and select the most suitable type of bone removal knife with adjustable blade angle from the straight type, oblique 15°, oblique 20°, oblique 30° and oblique 40° types to facilitate the removal of bone blocks in different parts such as the mandibular ascending ramus, mandibular molar area, chin, etc.;

[0066] Step 3: Insert the straight blade-shaped end of the blade portion 3 suitable for the block bone cutting line into the bottom of the block bone cutting line to pry and remove a larger volume of cortical and cancellous bones.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model 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 make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A bone removal knife with adjustable blade angle, comprising a handle portion (1), a rod portion (2) and a blade portion (3), wherein the handle portion (1) and the rod portion (2) are integrally formed, and the blade portion (3) is arranged at the end of the rod portion (2), characterized in that: The end of the rod portion (2) is detachably connected to the blade portion (3); The blade portion (3) comprises a blade (31), the side surface of the blade (31) is in an arc shape, and the end of the blade (31) forms a cutting edge on a cutting surface; The projection of the cut surface of the end of the blade (31) on the longitudinal section passing through the center line of the rod (2) is a straight line perpendicular to the center line of the rod (2) or a non-perpendicular oblique line.

2. The bone removal knife with adjustable blade angle according to claim 1, characterized in that: The length of the blade (31) is less than 1 cm; The length of the projection of the cut surface at the end of the blade (31) on the longitudinal section passing through the center line of the rod (2) is 3 to 5 mm.

3. The bone removal knife with adjustable blade angle according to claim 1, characterized in that: comprising at least one blade set, wherein the blade set comprises a plurality of blades (3), The angle γ between the projection of the cut surface of the end of the blade (31) of the cutting portion (3) on the longitudinal section passing through the center line of the rod portion (2) and the cross section of the rod portion (2) satisfies: 0≤γ≤40°.

4. The bone removal knife with adjustable blade angle according to claim 3, characterized in that: When the projection of the cut surface of the end of the blade (31) on the longitudinal section passing through the center line of the rod (2) is a straight line perpendicular to the center line of the rod (2), the angle γ between the projection of the cut surface of the end of the blade (31) of the cutting edge portion (3) on the longitudinal section passing through the center line of the rod (2) and the cross section of the rod (2) is 0°; When the projection of the cut surface of the end of the blade (31) on the longitudinal section passing through the center line of the rod (2) is an oblique line that is not perpendicular to the center line of the rod (2), the angle γ between the projection of the cut surface of the end of the blade (31) of the cutting edge portion (3) on the longitudinal section passing through the center line of the rod (2) and the cross section of the rod (2) is 15°, 20°, 30° or 40°.

5. The bone removal knife with adjustable blade angle according to claim 1, characterized in that: A joint (20) is provided at the end of the rod (2), and a hexagonal nut hole (200) is provided in the joint (20); The blade portion (3) further comprises a hexagonal nut (30) and a transition section (32), wherein the transition section (32) is narrow at the bottom and wide at the top, and the hexagonal nut (30) is connected to the blade (31) via the transition section (32); The hexagonal nut (30) of the blade portion (3) is inserted into and embedded in the hexagonal nut hole (200) of the joint (20) of the rod portion (2).

6. The bone removal knife with adjustable blade angle according to claim 5, characterized in that: The wall of the joint (20) extends outward to form an external flange (21), and the outer wall of the external flange (21) is provided with an external thread; The outer flange (21) is provided with an end cover (22), a blade through hole is provided in the center of the end cover (22), a cover wall is provided at the edge of the end cover (22), and an internal thread is provided on the cover wall; The blade hole of the end cover (22) passes through the blade (31) and the transition section (32) of the blade (3) from bottom to top in sequence, and is connected to the outer flange (21) of the joint (20) through threads.

7. The bone removal knife with adjustable blade angle according to claim 5, characterized in that: The hexagonal nut (30), the transition section (32) and the blade (31) are integrally formed.

8. The bone removal knife with adjustable blade angle according to claim 6, characterized in that: The diameter of the hole of the blade portion of the end cover (22) is larger than the maximum outer diameter of the transition section (32) of the blade portion (3), but smaller than the outer diameter of the circumscribed circle of the hexagonal nut (30) of the blade portion (3).

9. The bone removal knife with adjustable blade angle according to claim 6, characterized in that: The outer diameter of the outer flange (21) is smaller than the outer diameter of the outer wall of the joint (20), and the outer diameter of the outer wall of the joint (20) is equal to the outer diameter of the cover wall of the end cover (22).

10. The bone removal knife with adjustable blade angle according to claim 1, characterized in that: The total length of the bone removal knife with adjustable blade angle does not exceed 20 cm.

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