JP2018000549A - Vertebral body spacer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique, when inserting a vertebral body spacer between vertebral bodies, capable of reducing friction resistance between the vertebral body spacer and the vertebral bodies.SOLUTION: A vertebral body spacer includes: first guide projection parts 30 disposed on a first surface 21 and extending in a direction along a third direction; second guide projection parts disposed on a second surface 22 and extending in a direction along the third direction; a first fitting projection part 50 disposed on a third surface 23; and a second fitting projection part 60 disposed on a fourth surface. When the vertebral body spacer is disposed between adjacent vertebral bodies, the third surface faces one vertebral body and the fourth surface faces the other vertebral body.SELECTED DRAWING: Figure 3

Description

  The present invention relates to vertebral body spacer technology.

  Conventionally, when an intervertebral disc located between two adjacent vertebral bodies is damaged and the original function is impaired, for example, a vertebral body spacer disposed between the two adjacent vertebral bodies is used instead of the intervertebral disc. Known (for example, Patent Documents 1 to 5).

Special table 2014-529310 gazette Japanese Patent No. 2855079 Japanese Patent No. 4197094 Japanese translation of Japanese translation of PCT publication No. 8-503876 JP-A-8-266565

  In the prior art, in order to prevent the vertebral body spacer from being detached from the vertebral body (displacement) in a state where the vertebral body spacer is disposed between the two vertebral bodies (arrangement state), the vertebral body spacer is disposed In a state, it has the protrusion part which bites into a vertebral body in the surface facing a vertebral body. The protrusion forms, for example, a concavo-convex structure extending along the direction intersecting the insertion direction of the vertebral body spacer between the vertebral bodies. Further, in the conventional technique, in order to reduce the load on the vertebral body, the vertebral body spacer is placed in a posture such that a surface (other surface) different from the surface on which the protrusion is arranged faces the vertebral body. May be inserted. In this case, after inserting the vertebral body spacer between the vertebral bodies, the vertebral body spacer is rotated so that the surface on which the protruding portion is formed faces the vertebral body. Thereby, a vertebral body spacer is arrange | positioned between vertebral bodies.

  In the conventional technique, when the vertebral body spacer is inserted between the vertebral bodies with the other surface facing the vertebral body, the contact area between the vertebral body and the other surface is large, so the frictional resistance at the time of insertion is low. In some cases, it was too high. When the frictional resistance is excessively high, an external force applied to the vertebral body spacer to insert the vertebral body spacer becomes excessive, and the vertebral body spacer may be damaged. Therefore, a technique that can reduce the frictional resistance between the vertebral body spacer and the vertebral body during insertion between the vertebral bodies is desired.

  The present invention has been made to solve the above-described problems, and can be realized as the following forms or application examples.

(1) According to one aspect of the present invention, the first surface and the second surface that face each other in the first direction, the third surface and the fourth surface that face each other in the second direction orthogonal to the first direction, A vertebral body spacer is provided that includes a spacer body having a first direction and a fifth surface and a sixth surface facing each other in a third direction orthogonal to the second direction, and is disposed between adjacent vertebral bodies. The The vertebral body spacer is disposed on the first surface and extends in a direction along the third direction. The vertebral body spacer is disposed on the second surface and extends in a direction along the third direction. 2 guide protrusions, a first fitting protrusion disposed on the third surface, and a second fitting protrusion disposed on the fourth surface, wherein the vertebral body spacer is the adjacent vertebra When placed between the bodies, the third surface faces one of the vertebral bodies and the fourth surface faces the other vertebral body. According to this embodiment, when the vertebral body spacer is inserted between adjacent vertebral bodies along the third direction in a posture in which the first surface is opposed to one vertebral body and the second surface is opposed to the other vertebral body. In addition, the first guide protrusion is in contact with one vertebral body, and the second guide protrusion is in contact with the other vertebral body. Thereby, when the 1st guide protrusion part and the 2nd guide protrusion part are not arrange | positioned, the contact area of the vertebral body spacer at the time of insertion between vertebral bodies and a vertebral body can be reduced. Therefore, since frictional resistance during insertion between vertebral bodies can be reduced, the possibility that the external force applied to the vertebral body spacers to insert the vertebral body spacers between the vertebral bodies becomes excessively large can be reduced.

(2) It is the said form, Comprising: Each of the said 1st guide protrusion part and the said 2nd guide protrusion part are provided with two or more, Two of these said 1st guide protrusion parts are in said 2nd direction. Two of the plurality of second guide protrusions may be positioned across the center of the spacer body in the second direction. According to this aspect, the two first guide protrusions and the two second guide protrusions are positioned across the center of the spacer body in the second direction. Thereby, at the time of insertion of the vertebral body spacer, it is possible to reduce the possibility that the vertebral body spacer is inclined to either one side of the center of the spacer body in the second direction.

(3) It is the said form, Comprising: The said 1st guide protrusion part has a 1st top part which forms the ridgeline along the said 3rd direction, and the said 2nd guide protrusion part followed the said 3rd direction. You may have the 2nd top part which forms a ridgeline. According to this configuration, the frictional resistance during insertion between the vertebral bodies can be further reduced, so that the possibility that the external force applied to the vertebral body spacers to insert the vertebral body spacers between the vertebral bodies becomes excessively large is further increased. Can be reduced.

(4) It is the said form, Comprising: The said 1st top part and the said 2nd top part may each form a corner | angular. According to this configuration, the frictional resistance during insertion between vertebral bodies can be further reduced, so that the external force applied to the vertebral body spacers to insert the vertebral body spacers between the vertebral bodies can be excessively increased. It can be further reduced.

(5) It is the said form, Comprising: The internal angle of the said 1st top part which forms the said angle | corner is 90 degree | times or more,
The inner angle of the second apex that forms the corner may be 90 degrees or more. According to this embodiment, when the vertebral body spacer is inserted and arranged between the vertebral bodies, the possibility that the first top portion and the second top portion are damaged can be reduced.

(6) It is the said form, Comprising: The said 1st fitting protrusion has a 1st side part connected to the said 3rd surface, and forms the side surface of the said 1st fitting protrusion, The said 2nd fitting The protrusion has a second side surface portion that is connected to the fourth surface and forms a side surface of the second fitting protrusion, and includes at least the third surface, the fourth surface, the first side surface portion, and A bone bonding layer for bonding to the vertebral body may be formed on each surface of the second side surface portion. According to this embodiment, after the vertebral body spacer is disposed between the vertebral bodies, the connectivity between the vertebral body and the vertebral body spacer can be improved.

(7) It is the said form, Comprising: The said bone joint layer may be formed in the whole surface of the said vertebral body spacer. According to this embodiment, after the vertebral body spacer is disposed between the vertebral bodies, the connectivity between the vertebral body and the vertebral body spacer can be further improved.

(8) It is the said form, Comprising: The porous layer which receives the growth of the said vertebral body may be sufficient as the said bone bond layer. According to this aspect, since the growth of the vertebral body can be accepted by the porous layer, the connectivity between the vertebral body and the vertebral body spacer can be improved.

(9) It is the said form, Comprising: The said porous layer may have a bioactive substance. According to this embodiment, when a vertebral body spacer is arranged between vertebral bodies, a chemical reaction between the bioactive substance and the bone tissue of the vertebral body starts, and new bone can be rapidly formed. Thereby, a vertebral body and a vertebral body spacer can be combined at an early stage.

(10) In the above form, the bioactive substance may be calcium phosphate. According to this embodiment, calcium phosphate can be used as the bioactive substance.

(11) It is the said form, Comprising: Hydroxyapatite may be sufficient as the said calcium phosphate. According to this embodiment, hydroxyapatite can be used as calcium phosphate.

(12) It is the said form, Comprising: You may have a 1st through-hole penetrated over the said 3rd surface and the said 4th surface further. According to this aspect, when the bone tissue of the vertebral body facing the third surface or the fourth surface grows, the grown bone tissue can be received by the first through hole. The bondability can be further improved.

(13) It is the said form, Comprising: You may have a 2nd through-hole penetrated over the said 1st surface and the said 2nd surface further. According to this aspect, when the bone tissue of the vertebral body grows to a position facing the first surface and the second surface, the grown bone tissue can be received by the second through hole. The bondability with the spacer can be further improved.

(14) It is the said form, Comprising: The said 1st fitting protrusion part and the said 2nd fitting protrusion part are extended along the said 1st direction, and the said 1st fitting is seen in planar view seen from the said 2nd direction. The direction along the first direction, which is the direction in which the mating protrusion extends, and the direction along the first direction, in which the second fitting protrusion extends, may intersect each other. According to this aspect, after the vertebral body spacer is arranged between the vertebral bodies, the possibility that the vertebral body spacer is displaced from the original arrangement position can be reduced.

(15) In the above embodiment, the vertebral body spacer may be made of a material mainly composed of a polymer material. According to this embodiment, the vertebral body spacer can be produced using a material mainly composed of a polymer material.

(16) It is the said form, Comprising: The material selected from the group which consists of resin containing polyether ether ketone and carbon fiber and polyether ether ketone may be sufficient as the said polymeric material. In general, polyetheretherketone is biocompatible and has mechanical properties similar to bone. According to this embodiment, the polymer material is a material selected from the group consisting of polyether ether ketone and a resin including carbon fiber and polyether ether ketone, so that the connectivity between the vertebral body and the vertebral body spacer Can be further improved.

  It should be noted that the present invention can be realized in various forms, and in addition to the vertebral body spacer, for example, can be realized in an aspect such as a vertebral body spacer manufacturing method.

It is a 1st figure for demonstrating the usage example of a vertebral body spacer. It is the figure which looked at the figure shown in FIG. 1 from the paper surface upper side. It is a 1st perspective view of a vertebral body spacer. It is a 2nd perspective view of a vertebral body spacer. It is a 3rd perspective view of a vertebral body spacer. It is a 4th perspective view of a vertebral body spacer. It is a top view of a vertebral body spacer. It is a side view of a vertebral body spacer. It is a processing flow which shows the arrangement | positioning process of the vertebral body spacer between vertebral bodies. It is a processing flow which shows the manufacturing process of a vertebral body spacer. It is a figure for demonstrating the vertebral body spacer of a 1st modification. It is a figure for demonstrating the 1st deformation | transformation aspect of a 1st guide protrusion and a 2nd guide protrusion. It is a schematic diagram for demonstrating the 2nd deformation | transformation aspect of a 1st guide protrusion part and a 2nd guide protrusion part. It is a schematic diagram for demonstrating a specific site | part.

A. Embodiment:
FIG. 1 is a first diagram for explaining an example of use of a vertebral body spacer 20 as an embodiment of the present invention. FIG. 2 is a view of the view shown in FIG. 1 as viewed from the upper side of the drawing. The vertebral body spacer 20 is an instrument (biological implant) that is placed between the adjacent first vertebral body 10A and the second vertebral body 10B and is implanted in the body. For example, the vertebral body spacer 20 is disposed between the first vertebral body 10A and the second vertebral body 10B instead of the damaged intervertebral disc. In the present embodiment, as shown in FIG. 2, two vertebral body spacers 20 are arranged side by side between the first vertebral body 10A and the second vertebral body 10B. When the first vertebral body 10A and the second vertebral body 10B are used without distinction, the vertebral body 10 is used.

  FIG. 3 is a first perspective view of the vertebral body spacer 20. FIG. 4 is a second perspective view of the vertebral body spacer 20. FIG. 5 is a third perspective view of the vertebral body spacer 20. FIG. 6 is a fourth perspective view of the vertebral body spacer 20. FIG. 7 is a top view of the vertebral body spacer 20. FIG. 8 is a side view of the vertebral body spacer 20. 3 to 6 and 8, the boundary between the third surface 23 and the first fitting protrusion 50 and the boundary between the fourth surface 24 and the second fitting protrusion 60 are easy to understand. Therefore, a broken line is attached. 3 is a cross-sectional view of the vertebral body spacer 20, and a single hatched portion indicates a dense main body portion 29A, and a cross hatched portion indicates an osteosynthesis layer 29B. Yes. Also, the first direction as the short direction of the vertebral body spacer 20 is denoted by “SD”, the second direction as the thickness direction is denoted by “TD”, and the third direction as the longitudinal direction. Is denoted by “LD”. The first direction SD, the second direction TD, and the third direction LD are orthogonal to each other. Further, the first direction SD, the second direction TD, and the third direction LD are straight directions, respectively.

  The vertebral body spacer 20 (FIG. 3) includes a spacer body 20A, a first guide protrusion 30, a second guide protrusion 40 (FIG. 4), a first fitting protrusion 50, and a second fitting protrusion. 60.

  The spacer main body 20A (FIG. 3) is a substantially rectangular parallelepiped hexahedron. The spacer body 20A has a first surface 21, a second surface 22, a third surface 23, a fourth surface 24 (FIG. 6), a fifth surface 25, and a sixth surface 26 (FIG. 4). . Each surface of the hexahedron is formed by the first surface 21 to the sixth surface 26. The first surface 21 to the fourth surface 24 are substantially flat surfaces, and the fifth surface 25 and the sixth surface 26 are flat surfaces.

  The first surface 21 and the second surface 22 face each other in the first direction SD. The third surface 23 and the fourth surface 24 oppose each other in the second direction TD. The third surface 23 and the fourth surface 24 intersect with the first surface 21 and the second surface 22, respectively. The fifth surface 25 and the sixth surface 26 face each other in the third direction LD. The fifth surface 25 and the sixth surface intersect with the first surface 21 to the fourth surface 24, respectively. The third surface 23 and the fourth surface 24 (FIG. 8) correspond to the distance between the first vertebral body 10A and the second vertebral body 10B, and the length of the spacer body 20A in the second direction TD is the fifth surface 25. It inclines so that it may become large as it goes to the 6th surface 26 side from the side.

  When inserting the vertebral body spacer 20 between the vertebral bodies 10A and 10B, the posture is such that the first surface 21 faces the first vertebral body 10A and the second surface 22 faces the second vertebral body 10B. The vertebral body spacer 20 is moved along the direction (insertion direction) from the fifth surface 25 toward the sixth surface 26 in the third direction LD. That is, the sixth surface 26 forms a tip surface in the insertion direction. After insertion, the vertebral body spacer 20 is rotated 90 degrees about the third direction LD so that the third surface 23 faces the first vertebral body 10A and the fourth surface 24 faces the second vertebral body 10B. . Thereby, the vertebral body spacer 20 is disposed between the vertebral bodies 10A and 10B. When inserting and arranging the vertebral body spacer 20 between the vertebral bodies 10A and 10B, a rod-shaped jig (described later) that can hold the vertebral body spacer 20 is used.

  In each of the first surface 21, the second surface 22, the third surface 23, and the fourth surface 24, the end surface on the side connected to the sixth surface 26 is an outwardly convex R surface (curved surface). RF is formed. Thereby, when inserting the vertebral body spacer 20 between the vertebral bodies 10A and 10B and when rotating the vertebral body spacer 20 after the insertion, the possibility that the vertebral body 10 is damaged by the vertebral body spacer 20 can be reduced. . Further, the vertebral body spacer 20 can be smoothly rotated by the R surface RF.

  The vertebral body spacer 20 further includes a first guide protrusion 30 (FIG. 3) and a second guide protrusion 40 (FIG. 4).

  The first guide protrusion 30 (FIG. 3) is disposed on the first surface 21. Specifically, the first guide protrusion 30 protrudes from the first surface 21. When the vertebral body spacer 20 is inserted between the vertebral bodies 10A and 10B (at the time of insertion), the first guide protrusion 30 abuts on the first vertebral body 10A and inserts the vertebral body spacer 20 in the third direction LD. To guide you.

  Two first guide protrusions 30 are provided at regular intervals in the second direction TD. As shown in FIG. 8, the two first guide protrusions 30 are located across the center CT of the spacer body 20 </ b> A in the second direction TD. The first guide protrusion 30 extends in a direction along the third direction LD. The “along direction” may not be completely parallel to the direction serving as the comparison reference (the third direction LD in this paragraph), and may intersect the direction serving as the comparison reference. For example, you may cross | intersect so that an angle within 25 degrees may be formed with the direction used as a comparison reference. In the present embodiment, the first guide protrusion 30 extends parallel to the third direction LD. The first guide protrusion 30 (FIGS. 3 and 4) extends continuously from the end of the first surface 21 on the fifth surface 25 side to the end of the sixth surface 26 side. In other embodiments, the first guide protrusion 30 is discontinuously spaced from the end on the fifth surface 25 side to the end on the sixth surface 26 side with a predetermined interval in the direction along the third direction LD. Further, in another embodiment, the first guide protrusion 30 extends from the end on the fifth surface 25 side to the end on the sixth surface 26 side. It does not have to be. For example, the first guide protrusion 30 may extend along the third direction LD so as to have a length that is at least half the length of the spacer body 20A in the third direction LD.

  The first guide protrusion 30 (FIG. 3) has a triangular cross section perpendicular to the third direction LD. The first guide protrusion 30 is a portion where the first side surface 32 forming one side of the triangular shape, the second side surface 33 forming the other side of the triangular shape, and the first side surface 32 and the second side surface 33 intersect. A first top 35. The first top portion 35 is a portion of the first guide protrusion 30 that is farthest from the first surface 21. The 1st top part 35 forms the ridgeline along the 3rd direction LD because the 1st side surface 32 and the 2nd side surface 33 cross. In addition, the first top portion 35 forms a corner when the first side surface 32 and the second side surface 33 intersect. A ridge line is formed by connecting the corners. The inner angle A1 (FIG. 3) of the first apex portion 35 is preferably 90 degrees or more. Thereby, when inserting and arrange | positioning the vertebral body spacer 20 between the vertebral bodies 10 (for example, at the time of rotation after insertion), it is possible to reduce the possibility that the first top portion 35 is broken and damaged. Further, the inner angle A1 of the first apex portion 35 may be 120 degrees or less. By setting the inner angle A1 to 120 degrees or less, the width of the first guide protrusion 30 in the second direction TD can be suppressed. Moreover, the 1st top part 35 of the part formed in R surface RF among the 1st guidance protrusion parts 30 forms round (curve) 35R (FIG. 4). Thereby, when inserting the vertebral body spacer 20 between the vertebral bodies 10A and 10B and when rotating the vertebral body spacer 20 after the insertion, the possibility that the vertebral body 10 is damaged by the vertebral body spacer 20 can be reduced. .

  The second guide protrusion 40 (FIG. 4) is disposed on the second surface 22. Specifically, the second guide protrusion 40 protrudes from the second surface 22. When the vertebral body spacer 20 is inserted, the second guide protrusion 40 contacts the second vertebral body 10A and guides the insertion of the vertebral body spacer 20 in the third direction LD.

  Two second guide protrusions 40 are provided at regular intervals in the second direction TD. The two second guide protrusions 40 are arranged at positions that overlap the two first guide protrusions 30 in the first direction SD across the spacer body 20A. Similar to the first guide protrusion 30, the two second guide protrusions 40 are located across the center CT (FIG. 8) of the spacer body 20 </ b> A in the second direction TD. The second guide protrusion 40 extends in a direction along the third direction LD. In the present embodiment, the second guide protrusion 40 extends parallel to the third direction LD. The second guide protrusion 40 (FIGS. 3 and 4) extends continuously from the end of the second surface 22 on the fifth surface 25 side to the end of the sixth surface 26 side. In another embodiment, the second guide protrusion 40 is discontinuously spaced from the end on the fifth surface 25 side to the end on the sixth surface 26 side with a predetermined interval in the direction along the third direction LD. The second guide protrusion 40 may extend from the end on the fifth surface 25 side to the end on the sixth surface 26 side in another embodiment. It does not have to be. For example, the second guide protrusion 40 may extend along the third direction LD so as to have a length that is at least half the length of the spacer body 20A in the third direction LD.

  The second guide protrusion 40 has a triangular cross section perpendicular to the third direction LD. The second guide protrusion 40 is a portion where the first side surface 42 that forms one side of the triangular shape, the second side surface 43 that forms the other side of the triangular shape, and the first side surface 42 and the second side surface 43 intersect. A second top 45. The second top 45 is the portion of the second guide protrusion 40 that is farthest from the second surface 22. The 2nd top part 45 forms the ridgeline along the 3rd direction LD because the 1st side 42 and the 2nd side 43 cross. Further, the second top portion 45 forms a corner when the first side surface 42 and the second side surface 43 intersect. A ridge line is formed by connecting the corners. The internal angle B1 (FIG. 4) of the second apex 45 is preferably 90 degrees or more. Thereby, at the time of rotation after insertion of the vertebral body spacer 20, the possibility that the second apex portion 45 is broken or the like can be reduced. Further, the inner angle B1 of the second apex 45 may be 120 degrees or less. By setting the inner angle B1 to 120 degrees or less, the width of the second guide protrusion 40 in the second direction TD can be suppressed. Moreover, the 2nd top part 45 of the part formed in R surface RF among the 2nd guide protrusion parts 40 forms 45 (R) (curve). Thereby, when inserting the vertebral body spacer 20 between the vertebral bodies 10A and 10B and when rotating the vertebral body spacer 20 after the insertion, the possibility that the vertebral body 10 is damaged by the vertebral body spacer 20 can be reduced. .

  The vertebral body spacer 20 further includes a first fitting protrusion 50 (FIG. 5), a second fitting protrusion 60 (FIG. 6), a first through hole 27 (FIG. 5), and a first sub through hole. 28A (FIG. 6), a second sub through hole 28B (FIG. 5), a third sub through hole 28C (FIG. 5), and a fourth sub through hole 28D (FIG. 4).

  The first through hole 27 (FIGS. 5 and 7) is a single hole that penetrates the vertebral body spacer 20 in the second direction TD, and penetrates from the third surface 23 to the fourth surface 24. The first sub through hole 28A (FIG. 6) is a hole that allows the first surface 21 and the first through hole 27 to communicate with each other, and penetrates a wall having the first surface 21 as an outer surface. Three first sub through holes 28A are arranged side by side along the third direction LD. The second sub through hole 28B (FIG. 5) is a hole that allows the second surface 22 and the first through hole 27 to communicate with each other, and penetrates a wall having the second surface 22 as an outer surface. Three second sub through holes 28B are arranged side by side along the third direction LD. The third sub through hole 28C (FIG. 5) is a single hole that allows the fifth surface 25 and the first through hole 27 to communicate with each other, and penetrates a wall having the fifth surface 25 as an outer surface. The fourth sub through hole 28 </ b> D (FIG. 6) is a single hole that allows the sixth surface 26 and the first through hole 27 to communicate with each other, and penetrates a wall having the sixth surface 26 as an outer surface. Here, the first sub through hole 28 </ b> A and the second sub through hole 28 </ b> B can be regarded as through holes penetrating over the first surface 21 and the second surface 22. The first sub through hole 28A and the second sub through hole 28B correspond to the “second through hole” described in the means for solving the problem.

  The first fitting protrusion 50 (FIG. 5) is disposed on the third surface 23. Specifically, the first fitting protrusion 50 protrudes from the third surface 23. The first fitting protrusion 50 bites into the first vertebral body 10 </ b> A when it is rotationally arranged between the vertebral bodies 10. The first fitting protrusion 50 extends in a direction along the first direction SD. The first fitting protrusion 50 extends from the end on the first surface 21 side of the third surface 23 to the end on the second surface 22 side. The first fitting protrusion 50 is divided in the first direction SD by the first through hole 27. In other words, in the first direction SD, the two first fitting protrusions 50 are positioned so as to sandwich the first through hole 27. A plurality of first fitting protrusions 50 are arranged side by side in the third direction LD, and form an uneven structure on the third surface 23.

  The first fitting protrusion 50 has a triangular cross section perpendicular to the first direction SD. The first fitting protrusion 50 includes a first side surface 52 that forms one side of the triangular shape, a second side surface 53 that forms the other side of the triangular shape, and a portion where the first side surface 52 and the second side surface 53 intersect. And a first fitting top 55. The first fitting top 55 is a portion of the first fitting protrusion 50 that is farthest from the third surface 23. The 1st fitting top part 55 forms the ridgeline along 1st direction SD by the 1st side surface 52 and the 2nd side surface 53 crossing. Moreover, the 1st fitting top part 55 forms an angle | corner (for example, the angle | corner which has an internal angle of 30 degrees-60 degrees) by the 1st side surface 52 and the 2nd side surface 53 crossing. The first side surface 52 and the second side surface 53 have one end connected to the third surface 23 and the other end forming a corner. The first side surface 52 and the second side surface 53 form the side surface of the first fitting protrusion 50. The first side surface 52 and the second side surface 53 correspond to the “first side surface portion” described in the means for solving the problem.

  The second fitting protrusion 60 (FIG. 6) is disposed on the fourth surface 24. Specifically, the second fitting protrusion 60 protrudes from the fourth surface 24. The second fitting protrusion 60 bites into the second vertebral body 10B when it is rotationally arranged between the vertebral bodies 10. The second fitting protrusion 60 extends in a direction along the first direction SD. The second fitting protrusion 60 extends from the end of the fourth surface 24 on the first surface 21 side to the end of the second surface 22 side. The second fitting protrusion 60 is divided in the first direction SD by the first through hole 27. In other words, in the first direction SD, the two second fitting protrusions 60 are positioned so as to sandwich the first through hole 27. A plurality of second fitting protrusions 60 are arranged side by side in the third direction LD to form a concavo-convex structure on the fourth surface 24.

  The second fitting protrusion 60 has a triangular cross section perpendicular to the first direction SD. The second fitting protrusion 60 includes a first side surface 62 that forms one side of the triangular shape, a second side surface 63 that forms the other side of the triangular shape, and a portion where the first side surface 62 and the second side surface 63 intersect. And a second fitting top portion 65. The second fitting top portion 65 is the portion of the second fitting protrusion 60 that is farthest from the fourth surface 24. The 2nd fitting top part 65 forms the ridgeline along 1st direction SD because the 1st side surface 62 and the 2nd side surface 63 cross. Moreover, the 2nd fitting top part 65 forms an angle | corner (for example, angle | corner which has an internal angle of either 30 degrees-60 degrees) by the 1st side surface 62 and the 2nd side surface 63 crossing. The first side surface 62 and the second side surface 63 are connected to the fourth surface 24 at one end side and the other end side forms a corner. The first side surface 62 and the second side surface 63 form a side surface of the second fitting protrusion 60. The first side surface 62 and the second side surface 63 correspond to the “second side surface portion” described in the means for solving the problem.

  The vertebral body spacer 20 is made of a material mainly composed of a polymer material (50% by mass or more). Here, when the vertebral body spacer 20 is formed of a material having a metal material as a main component, it has high strength, but may have a high elastic modulus and lack toughness, and a portion where a large load is continuously applied. If it is placed in the position, there is a problem that stress shielding occurs due to a difference in mechanical properties with surrounding bones, and there is a problem that it is not directly coupled to bones. In addition, when bioceramics such as hydroxyapatite are selected as the material for the artificial bone, the bioceramics usually have good biocompatibility, high bioactivity, and excellent bone binding properties, but external Since it is vulnerable to impact, there is a problem that it cannot be used for a part where a large load is applied instantaneously. By forming the vertebral body spacer 20 from a material mainly composed of a polymer material, the possibility of the above-described problems occurring can be reduced.

  In the present embodiment, the vertebral body spacer 20 (FIG. 3) has a dense main body portion 29A made of a polymer material and an osteosynthesis layer 29B formed on the entire surface of the main body portion 29A. The bone bonding layer 29 </ b> B is a layer for bonding with the vertebral body 10. In the present embodiment, the bone bonding layer 29 </ b> B is a porous layer that accepts the growth of the vertebral body 10. For example, polyether ether ketone (PEEK) can be used as the polymer material of the main body portion 29A. The polymer material may be a resin containing carbon fiber. For example, the vertebral body spacer 20 may have a composition of 70 to 90% by mass of PEEK and 10 to 30% by mass of carbon fiber.

PEEK is biocompatible and has mechanical properties similar to bone. Therefore, when PEEK is adopted as a material for forming the vertebral body spacer 20, the connectivity with the vertebral body 10 can be improved. For example, when the vertebral body spacer 20 is disposed at a site where a large load is continuously applied for a long period of time, it is possible to suppress a decrease in bone density and a decrease in bone density that may occur due to stress shielding, that is, shielding of stress applied to the bone. . The bone bonding layer 29B has an opening on the surface and a hole communicating to the inner side. The bone bonding layer 29B is formed by performing various processes to be described later on the base material that is the base of the vertebral body spacer 20 formed by PEEK. The bone bonding layer 29B may have a bioactive substance on the inner wall surface or surface of the hole. Thereby, after the vertebral body spacer 20 is disposed between the first vertebral body 10A and the second vertebral body 10B, a chemical reaction between the bioactive substance and the bone tissue of the living body starts, and formation of new bone is started. Promptly. Therefore, the bone (vertebral body 10) and the vertebral body spacer 20 can be joined at an early stage. The bioactive substance is not particularly limited as long as it has high affinity with a living body and has a property of chemically reacting with bone tissue. For example, calcium phosphate-based material, bioglass, crystallized glass (also called glass ceramics) ), Calcium carbonate and the like. Examples of calcium phosphate materials include calcium hydrogen phosphate, calcium hydrogen phosphate hydrate, calcium dihydrogen phosphate, calcium dihydrogen phosphate hydrate, α-type tricalcium phosphate, β-type tricalcium phosphate, Examples thereof include dolomite, tetracalcium phosphate, octacalcium phosphate, hydroxyapatite, fluorapatite, carbonate apatite, and chlorapatite. Examples of the bioglass include SiO ₂ —CaO—Na ₂ O—P ₂ O ₅ glass, SiO ₂ —CaO—Na ₂ O—P ₂ O ₅ —K ₂ O—MgO glass, and SiO ₂ —. Examples include CaO—Al ₂ O ₃ —P ₂ O ₅ glass. Examples of the crystallized glass include SiO ₂ —CaO—MgO—P ₂ O ₅ glass (also referred to as apatite wollastonite crystallized glass), CaO—Al ₂ O ₃ —P ₂ O ₅ glass, and the like. Is mentioned. These calcium phosphate materials, bioglass, and crystallized glass are, for example, “Chemical Handbook Applied Chemistry 6th Edition” (The Chemical Society of Japan, published on January 30, 2003, Maruzen Co., Ltd.), “Development of Bioceramics” And Clinical "(edited by Hideki Aoki et al., Published on April 10, 1987, Quintessence Publishing Co., Ltd.).

  As the bioactive substance, a calcium phosphate-based material is particularly preferable in terms of excellent bioactivity. More preferably, hydroxyapatite is used. This is because hydroxyapatite is similar in composition, structure, and properties to actual bones, and thus has excellent stability in the body environment and does not exhibit remarkable solubility in the body.

  FIG. 9 is a processing flow showing a process of arranging the vertebral body spacer 20 between the vertebral bodies 10. First, the vertebral body spacer 20 is held by the jig 70 (step S10). The jig 70 may be configured to hold the vertebral body spacer 20. For example, the jig 70 may be configured to hold the vertebral body spacer 20 and inserted into the third auxiliary through hole 28 </ b> C opened in the fifth surface 25. Possible configurations can be used. Next, the vertebral body spacer 20 is inserted between the vertebral bodies 10A and 10B in such a posture that the first surface 21 faces the first vertebral body 10A and the second surface 22 faces the second vertebral body 10B ( Step S12). The insertion direction is a direction from the fifth surface 25 toward the sixth surface 26 in the third direction LD. The insertion of the vertebral body spacer 20 is performed by applying an external force in the insertion direction to the vertebral body spacer 20 via the jig 70. For example, an external force in the insertion direction is applied to the vertebral body spacer 20 by hitting the jig 70 with a hammer. Next, the vertebral body spacer 20 is rotated 90 degrees around the third direction LD so that the third surface 23 faces the first vertebral body 10A and the fourth surface 24 faces the second vertebral body 10B ( Step S14). After step S14, the jig 70 is removed from the vertebral body spacer 20. Through the steps S10 to S14, the vertebral body spacer 20 is arranged between the vertebral bodies 10A and 10B.

  FIG. 10 is a process flow showing the manufacturing process of the vertebral body spacer 20. First, a base material that is a base of the vertebral body spacer 20 is produced (step S20). Specifically, the base material is produced by cutting a plastic material (for example, PEEK) so as to have the shape of the vertebral body spacer 20. This base material has the external shape shown in FIGS. In addition, it may replace with cutting and may produce a base material by injection molding using a metal mold | die.

  Next, a large number of micropores are formed on the substrate surface (step S22). A well-known method can be employ | adopted as a method of forming a micropore on the base-material surface. For example, a method in which a plastic substrate is immersed in a corrosive solution such as concentrated sulfuric acid, concentrated nitric acid, or chromic acid for a predetermined time, and then the substrate is immersed in a cleaning solution that does not elute the plastic, such as pure water. Can be mentioned. When, for example, polyether ether ketone (PEEK) is used as the plastic, micropores can be formed by immersing PEEK in concentrated sulfuric acid for a predetermined time and then immersing it in pure water. A number of microporous layers formed on the surface of the base material become the bone bonding layer 29B.

  Next, a foaming agent holding base material in which the foaming agent is held on the surface of the base material having a large number of micropores is produced (step S24). The foaming agent may be any substance that can form a desired porous structure on the surface of a plastic substrate, and as such a foaming agent, an inorganic foaming agent such as carbonate or aluminum powder, Examples thereof include organic foaming agents such as azo compounds and isocyanate compounds. The foaming agent is preferably a substance that does not adversely affect the living body, and as such a foaming agent, carbonates are preferable, and examples thereof include sodium hydrogen carbonate, sodium carbonate, and potassium carbonate.

  Next, a foaming base material is produced from the foaming agent holding base material (step S26). Specifically, the foaming agent holding substrate is immersed for a predetermined time in a foaming solution that swells the plastic and foams the foaming agent, so that the swelling of the plastic and the foaming of the foaming agent proceed simultaneously. Thereafter, the foamed substrate is produced by immersing it in a coagulation solution that coagulates the swollen plastic. Examples of the foaming solution include acidic solutions such as concentrated sulfuric acid, hydrochloric acid, and nitric acid. When the material for forming the foaming agent holding substrate is PEEK and the foaming agent is carbonate, the sulfuric acid is preferably concentrated sulfuric acid having a concentration of 90% or more as the foaming solution. Examples of the coagulation solution, that is, a solution from which the plastic does not elute, include aqueous solutions such as water, acetone, and ethanol. When the material for forming the foamed substrate is PEEK, in addition to the above, there are aqueous solutions of inorganic acids such as sulfuric acid, nitric acid, phosphoric acid, hydrochloric acid and the like, water-soluble organic solvents having a concentration of less than 90%. Examples of the water-soluble organic solvent include N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, ethylene glycol, diethylene glycol, trietylene glycol, propylene glycol, diester. Alcohols such as propylene glycol, glycerol ethanol, propanol, butanol, pentanol, hexanol and the like and their aqueous solutions, polyethylene glycol, polypropylene glycol, polyvinyl pyrrolidone, etc. Mention may be made of molecules or their aqueous solutions and mixtures thereof.

  Next, the hydroxyapatite particles are immobilized on the surface of the foamed substrate (step S28). Thereby, the hydroxyapatite particles are immobilized on the inner wall surface and the surface of the bone bonding layer 29B. As the immobilization method, for example, the following method can be used. First, a dispersion solution in which hydroxyapatite particles are dispersed in an ethanol solution is prepared. Next, the foamed base material is immersed in the dispersion solution, and ultrasonic waves are applied to the dispersion solution in the immersed state. Thereby, the hydroxyapatite particles adhere uniformly to the surface of the foamed substrate. Next, the foamed substrate is taken out of the dispersion solution and dried under predetermined conditions (for example, at a temperature of about 230 ° C. for 20 minutes) to immobilize the hydroxyapatite particles. The vertebral body spacer 20 is produced by performing Step S20 to Step S28.

  According to the embodiment, the first guide protrusion 30 is disposed on the first surface 21, and the second guide protrusion 40 is disposed on the second surface 22 (FIGS. 3 and 4). Further, in a posture such that the first surface 21 faces the first vertebral body 10A and the second surface 22 faces the second vertebral body 10B, the fifth surface 25 to the sixth surface 26 in the third direction LD. The vertebral body spacer 20 is inserted between the vertebral bodies 10A and 10B along the direction (insertion direction). Thereby, the contact area of the vertebral body spacer 20 and the vertebral bodies 10A, 10B at the time of insertion between the vertebral bodies 10A, 10B than when the first guide protrusions 30 and the second guide protrusions 40 are not arranged. Can be reduced. Therefore, since the frictional resistance during insertion between the vertebral bodies 10A and 10B can be reduced, the external force applied to the vertebral body spacer 20 to insert the vertebral body spacer 20 between the vertebral bodies 10A and 10B can be excessively increased. Can be reduced. Further, since the first guide protrusion 30 and the second guide protrusion 40 extend in the direction along the third direction LD that is the insertion direction, the vertebral body spacer 20 can be smoothly moved in the insertion direction at the time of insertion. .

  Moreover, according to the said embodiment, the two 1st guide protrusion parts 30 are located in the 1st surface 21 on both sides of center CT of the spacer main body 20A in the 2nd direction TD, and the two 2nd guide protrusion parts 40 are , Located on the second surface 22 across the center CT in the second direction TD (FIG. 8). Thereby, when inserting the vertebral body spacer 20, it is possible to reduce the possibility that the vertebral body spacer 20 is inclined to either one side of the center CT of the spacer body 20A in the second direction TD.

  Further, according to the embodiment, the first guide protrusion 30 has the first top 35 that forms a ridge line along the third direction LD, and the second guide protrusion 40 has a ridge line along the third direction LD. The second top portion 45 is formed (FIGS. 3 and 4). Thereby, the contact area between the first guide protrusion 30 and the first vertebral body 10A and the contact area between the second guide protrusion 40 and the second vertebral body 10B at the time of insertion between the vertebral bodies 10A and 10B. Can be further reduced. Therefore, since the frictional resistance at the time of insertion into the vertebral bodies 10A and 10B can be further reduced, the external force applied to the vertebral body spacer 20 to insert the vertebral body spacer 20 between the vertebral bodies 10A and 10B can be excessively increased. Can be further reduced. In particular, in the present embodiment, the first top portion 35 and the second top portion 45 each form a corner. As a result, the frictional resistance during insertion between the vertebral bodies 10A and 10B can be further reduced, so that the external force applied to the vertebral body spacer 20 to insert the vertebral body spacer 20 between the vertebral bodies 10A and 10B is excessive. The possibility of becoming larger can be further reduced.

  Further, according to the above embodiment, the vertebral body spacer 20 has the bone bonding layer 29B formed on the entire surface of the main body 29A (FIG. 3). Thereby, after arranging the vertebral body spacer 20 between the vertebral bodies 10A and 10B, the connectivity between the vertebral bodies 10A and 10B and the vertebral body spacer 20 can be further improved. In this embodiment, since the bone bonding layer 29B is a porous layer that accepts the growth of the vertebral bodies 10A and 10B, the porous layer accepts the growth of the vertebral bodies 10A and 10B, so that the vertebral bodies 10A and 10B and the vertebral body spacer 20 are received. Can be improved.

  Further, according to the embodiment, the vertebral body spacer 20 has the first sub through hole 28 </ b> A and the second sub through hole 28 </ b> B as the second through hole penetrating over the first surface 21 and the second surface 22. (FIGS. 3 and 4). As a result, when the bone tissue of the vertebral body 10 has grown to a position facing the first surface 21 and the second surface 22, the grown bone tissue is received by the first auxiliary through hole 28A and the second auxiliary through hole 28B. Therefore, the connectivity between the vertebral body 10 and the vertebral body spacer 20 can be further improved.

B. Variations:
In addition, this invention is not restricted to said embodiment, In the range which does not deviate from the summary, it can implement in a various aspect.

B-1. First modification:
In the above embodiment, in a plan view (for example, FIG. 7) viewed from the second direction TD, the direction in which the first fitting protrusion 50 extends (first direction SD) and the direction in which the second fitting protrusion 60 extends. However, the present invention is not limited to this, and the direction in which the first fitting protrusion 50 extends and the direction in which the second fitting protrusion 60 extends are the first direction SD. Any direction along the line may be used. An example will be described below.

  FIG. 11 is a view for explaining a vertebral body spacer 20a of a first modification. FIG. 11 is a diagram corresponding to FIG. 7, and is a plan view of the vertebral body spacer 20a viewed from the second direction TD. In FIG. 11, the second fitting protrusion 60a located on the back side of the drawing is indicated by a dotted line for easy understanding. Further, the direction in which the first fitting protrusion 50a extends is denoted by “D1”, and the direction in which the second fitting protrusion 60a extends is denoted by “D2”. The difference between the vertebral body spacer 20a and the vertebral body spacer 20 (FIG. 7) is that, in a plan view (FIG. 11) viewed from the second direction, the direction D1 in which the first fitting protrusion 50a extends and the second fitting This is a point where the direction D2 in which the protruding portion 60a extends intersects. Since other configurations are the same as those in the above-described embodiment, the same configurations are denoted by the same reference numerals and description thereof is omitted. In a plan view viewed from the second direction TD, for example, the direction D1 and the direction D2 intersect each other so as to have an angle of 5 degrees with respect to the first direction SD. As described above, the direction D1 and the direction D2 cross each other, so that after the vertebral body spacer 20a is arranged in the vertebral bodies 10A and 10B, the vertebral body spacer 20a is shifted in the first direction SD in addition to the third direction LD. The possibility can be reduced. That is, the possibility that the vertebral body spacer 20a is displaced from the original arrangement position can be reduced.

B-2. Second modification:
In the above embodiment, the first top 35 of the first guide protrusion 30 and the second top 45 of the second guide protrusion 40 each form a corner (FIGS. 3 and 4), but the first surface The shape of the first guide protrusion 30 and the second guide protrusion 40 is arbitrary as long as the shape protrudes from 21 and the second surface 22. Below, the modification of the 1st guide protrusion 30 and the 2nd guide protrusion 40 is demonstrated.

  FIG. 12 is a diagram for explaining a first modification of the first guide protrusion 30a and the second guide protrusion 40a. FIG. 12 is a diagram schematically showing a cross section orthogonal to the third direction LD, and shows the first guide protrusion 30a, but the second guide protrusion 40a has the same shape. The first guide protrusion 30a and the second guide protrusion 40a have a semicircular cross section perpendicular to the direction in which they extend (for example, the third direction LD). The vertices of the semicircle form the first top portion 35a and the second top portion 45a. The first apex portion 35a and the second apex portion 45a are connected in a direction along the third direction LD to form a ridge line. When the vertebral body spacer 20 is inserted between the vertebral bodies 10A and 10B, the first apex portion 35a abuts on the first vertebral body 10A, and the second apex portion 45a abuts on the second vertebral body 10B. Even in this case, the contact area between the vertebral body spacer 20 and the vertebral bodies 10A and 10B at the time of insertion between the vertebral bodies 10A and 10B can be reduced. Therefore, since the frictional resistance during insertion between the vertebral bodies 10A and 10B can be reduced, the external force applied to the vertebral body spacer 20 to insert the vertebral body spacer 20 between the vertebral bodies 10A and 10B can be excessively increased. Can be reduced.

  FIG. 13 is a schematic diagram for explaining a second modification of the first guide protrusion 30b and the second guide protrusion 40b. FIG. 13 is a view corresponding to FIG. 12 and shows the first guide protrusion 30b, but the second guide protrusion 40b has the same shape. The first guide protrusion 30b and the second guide protrusion 40b have a rectangular cross section orthogonal to the direction in which they extend (for example, the third direction LD). One side (upper side) of the rectangular shape contacts the first vertebral body 10A and the second vertebral body 10B when the vertebral body spacer 20 is inserted between the vertebral bodies 10A and 10B. Even in this case, the contact area between the vertebral body spacer 20 and the vertebral bodies 10A and 10B at the time of insertion between the vertebral bodies 10A and 10B can be reduced. Therefore, since the frictional resistance during insertion between the vertebral bodies 10A and 10B can be reduced, the external force applied to the vertebral body spacer 20 to insert the vertebral body spacer 20 between the vertebral bodies 10A and 10B can be excessively increased. Can be reduced.

B-3. Third modification:
In the above embodiment, two first and second guide protrusions 30 and 40 are provided (FIGS. 3 and 4), but may be one, or may be three or more. Good.

B-4. Fourth modification:
In the above embodiment, the bone bonding layer 29B is a porous layer (FIG. 3), but may be any layer for bonding to the vertebral body 10. For example, the bone bonding layer 29B may be a layer formed of titanium, or may be formed of hydroxyapatite particles immobilized on the surface of the main body portion 29A. Moreover, in the said embodiment, although the bone bonding layer 29B was formed in the whole surface of 29 A of main-body parts, you may abbreviate | omit and may form only in the surface of a specific site | part. FIG. 14 is a schematic diagram for explaining a specific part. FIG. 14 is a cross section orthogonal to the third direction LD. The specific portion may be a portion facing the vertebral bodies 10A and 10B with a gap in the arrangement state of the vertebral body spacer 20 between the vertebral bodies 10A and 10B. For example, a specific part is a part which divides the recessed part of the uneven structure formed of the 1st fitting protrusion part 50 and the 2nd fitting protrusion part 60. FIG. Specifically, for example, on the third surface 23 side, the third surface 23 and the first side surface 52 and the second side surface 53 that are the first side surface portions are specific parts, and on the fourth surface 24 side, The 4th surface 24 and the 1st side surface 62 and the 2nd side surface 63 which are 2nd side surfaces are specific parts. In FIG. 14, the adjacent first fitting protrusions 50 are adjacent to each other, but may be arranged at intervals. Adjacent second fitting protrusions 60 may be similarly arranged with an interval therebetween. In this case, a part of the planar third surface 23 or a part of the planar fourth surface 24 is between the adjacent first fitting protrusions 50 and the adjacent second fitting protrusions 60. It is formed. Even if it does in this way, after arrange | positioning the vertebral body spacer 20 between the vertebral bodies 10A and 10B, the connectivity between the vertebral bodies 10A and 10B and the vertebral body spacer 20 can be improved.

B-5. Fifth modification:
In the above embodiment, the spacer body 20A has a substantially rectangular parallelepiped shape (FIGS. 3 and 4), but is not limited thereto. For example, at least a part of each of the surfaces 21 to 26 of the hexahedron may be a curved surface.

B-6. Sixth modification:
In the above embodiment, the first through hole 27, the third sub through hole 28C, and the fourth sub through hole 28D are each a single hole, and the first sub through hole 28A and the second sub through hole 28B are each 3 The number of the first through hole 27, the first sub through hole 28A, the second sub through hole 28B, the third sub through hole 28C, and the fourth sub through hole 28D is limited to these. It is not limited. For example, a plurality of (for example, two) first through holes 27, third sub through holes 28C, and fourth sub through holes 28D may be formed, or the first sub through hole 28A and the second sub through hole may be formed. Only one 28B may be formed.

B-7. Seventh modification:
In the said embodiment, in the 1st fitting protrusion part 50 extended along 1st direction SD, the distance from the 3rd surface 23 of the 1st fitting top part 55 is in any position along 1st direction SD. Although the same, the distance from the third surface 23 of the first fitting top 55 may be partially different along the first direction SD. Moreover, in the said embodiment, in the 2nd fitting protrusion part 60 extended along 1st direction SD, the distance from the 4th surface 24 of the 2nd fitting top part 65 is any position along 1st direction SD. However, the distance from the fourth surface 24 of the second fitting top 65 may be partially different along the first direction SD.

B-8. Eighth modification:
In the said embodiment, although the 1st fitting protrusion part 50 and the 2nd fitting protrusion part 60 extended in the direction along 1st direction SD, if it protrudes from the 3rd surface 23 or the 4th surface 24, it will be. However, the present invention is not limited to this. Examples of the shapes of the first fitting protrusion 50 and the second fitting protrusion 60 include, for example, a shape extending along the first direction SD, a column shape having the third surface 23 or the fourth surface 24 as a bottom surface, and a frustum shape. Alternatively, at least one shape selected from a cone shape and the like may be employed. The first fitting protrusion 50 and the second fitting protrusion 60 may be regularly arranged on the third surface 23 or the fourth surface 24, or may be irregularly arranged. Good.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the above effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 10A ... 1st vertebral body 10B ... 2nd vertebral body 20, 20a ... Vertebral body spacer 20A ... Spacer main body 21 ... 1st surface 22 ... 2nd surface 23 ... 3rd surface 24 ... 4th surface 25 ... 5th surface 26 ... 6th surface 27 ... 1st through-hole 28A ... 1st sub through-hole 28B ... 2nd sub through-hole 28C ... 3rd sub through-hole 28D ... 4th sub through-hole 29A ... Main-body part 29B ... Bone bonding layer 30, 30a, 30b ... 1st guide protrusion 32 ... 1st side surface 33 ... 2nd side surface 35, 35a ... 1st top part 40, 40a, 40b ... 2nd guide protrusion 42 ... 1st side surface 43 ... 2nd side surface 45, 45a ... 1st 2 top 50, 50a ... first fitting protrusion 52 ... first side 53 ... second side 55 ... first fitting top 60, 60a ... second fitting protrusion 62 ... first side 63 ... second side 65 ... 2nd fitting top part 70 ... Jig A1, B1 ... Interior angle CT ... Center LD ... 3rd Direction SD ... first direction TD ... the second direction

Claims (16)

A first surface and a second surface facing each other in the first direction; a third surface and a fourth surface facing each other in a second direction orthogonal to the first direction; and a first surface orthogonal to the first direction and the second direction. A vertebral body spacer for positioning between adjacent vertebral bodies, comprising a spacer body having a fifth surface and a sixth surface opposed in three directions,
A first guide protrusion disposed on the first surface and extending in a direction along the third direction;
A second guide protrusion disposed on the second surface and extending in a direction along the third direction;
A first fitting protrusion disposed on the third surface;
A second fitting protrusion disposed on the fourth surface,
When the vertebral body spacer is disposed between the adjacent vertebral bodies, the third surface faces one of the vertebral bodies, and the fourth surface faces the other vertebral body. Vertebral spacer. The vertebral body spacer according to claim 1,
A plurality of the first guide protrusions and the second guide protrusions are provided,
Two of the plurality of first guide protrusions are located across the center of the spacer body in the second direction,
Two of the plurality of second guide protrusions are located across the center of the spacer body in the second direction, and the vertebral body spacer is characterized in that: The vertebral body spacer according to claim 1 or 2,
The first guide protrusion has a first apex that forms a ridge line along the third direction,
The vertebral body spacer, wherein the second guide protrusion has a second apex that forms a ridge line along the third direction. The vertebral body spacer according to claim 3,
The vertebral body spacer, wherein the first apex portion and the second apex portion each form a corner. The vertebral body spacer according to claim 4,
The internal angle of the first apex that forms the corner is 90 degrees or more,
A vertebral body spacer, wherein an inner angle of the second apex forming the corner is 90 degrees or more. The vertebral body spacer according to any one of claims 1 to 5,
The first fitting projection has a first side surface connected to the third surface and forming a side surface of the first fitting projection,
The second fitting protrusion has a second side surface connected to the fourth surface and forming a side surface of the second fitting protrusion.
At least a surface of each of the third surface, the fourth surface, the first side surface portion, and the second side surface portion is formed with a bone bonding layer for bonding to the vertebral body. Vertebral spacer characterized by. The vertebral body spacer according to claim 6,
The vertebral body spacer is characterized in that the bone bonding layer is formed on the entire surface of the vertebral body spacer. The vertebral body spacer according to claim 6 or 7,
The vertebral body spacer, wherein the osteosynthesis layer is a porous layer that receives the growth of the vertebral body. The vertebral body spacer according to claim 8,
The vertebral body spacer, wherein the porous layer has a bioactive substance. The vertebral body spacer according to claim 9,
The vertebral body spacer, wherein the bioactive substance is calcium phosphate. The vertebral body spacer according to claim 10,
The vertebral body spacer, wherein the calcium phosphate is hydroxyapatite. The vertebral body spacer according to any one of claims 1 to 11, further comprising:
A vertebral body spacer having a first through-hole penetrating over the third surface and the fourth surface. The vertebral body spacer according to any one of claims 1 to 12, further comprising:
A vertebral body spacer having a second through-hole penetrating over the first surface and the second surface. The vertebral body spacer according to any one of claims 1 to 13,
The first fitting protrusion and the second fitting protrusion extend along the first direction,
In a plan view seen from the second direction, the first fitting protrusion extends in a direction along the first direction, and the second fitting protrusion extends in the first direction. A vertebral body spacer characterized by intersecting with the direction along. The vertebral body spacer according to any one of claims 1 to 14,
The vertebral body spacer is made of a material mainly composed of a polymer material. The vertebral body spacer according to claim 15,
The vertebral body spacer is characterized in that the polymer material is a material selected from the group consisting of polyetheretherketone and a resin containing carbon fiber and polyetheretherketone.

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