JPH05269160A - Bone filling-up material - Google Patents

Abstract

PURPOSE:To stably fix vertebral bodies positioned in the upper and the lower parts of the resected intervertebral disk against force in the compression tensile direction and the direction being orthogonal to the compression tensile direction, in the case the intervertebral disk which becomes a disorder is resected, in a vertebra disease such as hernia of the intervertebral disk, etc. CONSTITUTION:The bone filling-up material is embedded extending over vertebral bodies 3, 3 positioned in the upper and the lower parts of the resected intervertebral disk, and provided with a hollow member 5 for positioning opposed parts 307, 307 of the vertebral bodies 3, 3 position in the upper and the lower parts of the resected intervertebral disk in its inside, and fixing means 9, 503 for fixing the hollow member 5 to the vertebral bodies 3, 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bone substitute material used when an injured intervertebral disc is resected in the cervical vertebrae, the lumbar spine or the like.

[0002]

2. Description of the Related Art For example, as one of the operations for spinal disorders such as disc herniation, the intervertebral disc that has been obstructed is excised from the front (front side) of the patient, and the intervertebral bodies located above and below the excised disc are separated. A method of inserting a bone substitute material is used. As such a bone filling material, an autogenous bone collected from the iliac bone of a patient or a bone filling material made of so-called bioceramics such as alumina and hydroxyapatite is used.

[0003]

However, the conventional method is a method in which the opposing parts of the vertebral bodies located above and below the resected intervertebral disc are excised, and a bone prosthesis is inserted into that part from the front of the patient. This is a method of filling the space from which the intervertebral disc is removed with a bone substitute material. Therefore, according to the conventional method, the upper and lower vertebral bodies can be fixed against the force in the compression direction, but it is difficult to fix the upper and lower vertebral bodies against the force in the tensile direction or the direction orthogonal to the compressive tension direction. The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide bone replacement capable of stably fixing upper and lower vertebral bodies against a force in the compression tension direction and a force in a direction orthogonal to the compression tension direction. Is to provide wood.

[0004]

In order to achieve the above object, the bone prosthesis material according to the present invention is embedded over the vertebral bodies located above and below the excised intervertebral disc, and is applied to the vertebral bodies located above and below the excised disc. It is characterized in that it is provided with a hollow member in which the facing parts are located inside and a fixing means for fixing the hollow member to the vertebral body. Further, the present invention is characterized in that the hollow member has a cylindrical shape, and the fixing means includes a screw formed on the outer periphery of the hollow member. Further, the present invention is characterized in that a flange is provided at an end of the hollow member, and the fixing means includes a screw which is inserted through the flange and is coupled to a vertebral body. .. Further, the present invention is characterized in that the flange is formed integrally with the hollow member. Further, the invention is characterized in that the flange is formed separately from the hollow member. Further, the present invention is characterized in that the hollow member is formed with a large number of holes communicating the inside and the outside of the hollow member.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional side view of the bone prosthesis material according to the first embodiment in use, and FIG. Reference numeral 1 is a spinal cord, 3 is a vertebral body, and is a portion obtained by cutting off an injured intervertebral disc.
The bone filling material 5 is fixed to the upper and lower vertebral bodies 3, 3 by the plate 7 and the two screws 9.

As shown in the side view of FIG. 3, the sectional side view of FIG. 4, and the front view of FIG.
And a trapezoidal screw 50 formed on the outer periphery of the cylindrical body 501.
As shown in FIG. 1, the length of the cylindrical body 501 is formed such that the vertebral body portion 311 remains on the spinal cord 1 side in a state of being embedded over the upper and lower vertebral bodies 3, 3. The body 501 is provided with a large number of holes 505 which communicate the inside and the outside of the cylindrical body 501. Further, as shown in FIG. 5, in the screw thread forming the trapezoidal screw 503, six screw holes 507 are arranged at equal intervals in the circumferential direction when viewed from one end face of the cylindrical body 501, and the six screw holes 507 are formed on the shaft of the cylindrical body 501. It is formed by penetrating each thread parallel to the core. The bone filling material 5 having such a structure is formed of a titanium alloy and is coated with a calcium phosphate-based compound. In the examples, a hydroxyapatite porous body is used.

The plate 7 is shown in front view in FIG.
As shown in the sectional side view, it is composed of a small-diameter cylindrical portion 701 and a circular flange portion 703 at the end thereof. The outer diameter of the cylindrical portion 701 is formed to fit into the inner peripheral surface of the cylindrical body 501, and the outer diameter of the flange portion 703 is formed to be substantially the same as the outer diameter of the trapezoidal screw 503. The flange portion 703 is provided with a screw insertion hole 705 having a size corresponding to the screw hole 507 in the circumferential direction.
It is formed at the same interval as the interval of 7. The plate 7 having such a structure is formed of a titanium alloy and is coated with a calcium phosphate-based compound. In the examples, a hydroxyapatite porous body is used.

As shown in FIG. 1, the screw 9 is composed of a screw portion 901 and a head portion 903. The screw part 9
01 is formed so as to be screwed into the screw hole 507 of the trapezoidal screw 503, and the length thereof is inserted from the screw insertion hole 705 of the flange portion 703 as shown in FIG. It is formed with dimensions up to. The screw 9 having such a configuration is formed of a titanium alloy and is coated with a calcium phosphate-based compound. In the examples, a hydroxyapatite porous body is used.
In this embodiment, the plate 7 corresponds to the flange in the claims, and the trapezoidal screw 503 and the two screws 9 correspond to the fixing means.

Next, a procedure for cutting off an intervertebral disc which has become an obstacle and fixing the vertebral bodies 3, 3 located above and below the cut intervertebral disc with the bone filling material 5 will be described with reference to FIG. First, an annular groove 301 having a size in which the cylindrical body 501 is fitted over the vertebral bodies 3 and 3 located above and below the intervertebral disc in which the intervertebral disc is removed.
To form. Further, a screw groove 303 into which the trapezoidal screw 503 is screwed is formed on the outer peripheral portion of the annular groove 301. Also,
Small holes having a size smaller than the screw hole 507 of the trapezoidal screw 503 are formed in the upper and lower vertebral bodies 3, 3 respectively with a length corresponding to the length of the screw 9. As will be described later, the position of this small hole is such that when the bone filling material 5 is rotated to fit the cylindrical body 501 into the annular groove 301, as shown in FIG. 1, among the six screw holes 507. The two screw holes 507 correspond to the positions along the extending direction of the spinal cord 1. Further, a concave portion 305 in which the tubular portion 701 of the plate 7 is fitted and accommodated is formed in a portion where the vertebral bodies 3 and 3 located above and below face each other.

Next, a trapezoidal screw 503 is screwed into the thread groove 303, the cylindrical body 501 is fitted into the annular groove 301 while rotating the bone filling material 5, and the end face of the bone filling material 5 is slightly vertebral body 3. , 3 until the bone prosthesis 5 is placed on both sides of the vertebral body 3,
3 so that inside the cylindrical body 501, the facing portions 307, 3 of the upper and lower vertebral bodies 3, 3
07 remains. Then, two screw holes 507 of the six screw holes 507 are aligned with the small holes, respectively, and the bone filling material 5
Stop rotating.

Next, the cylindrical portion 70 is formed on the inner peripheral surface of the cylindrical body 501.
1 is fitted to accommodate the cylindrical portion 701 in the recess 305, and the screw insertion hole 705 of the plate 7 is aligned with the screw hole 507 and the small hole. Next, the two screws 9 are screwed into the screw holes 507 and the small holes from the corresponding screw insertion holes 705, and screwed until the head 903 comes into contact with the plate 7, and the operation is completed.

According to the present embodiment, the bone prosthesis 5 is embedded and fixed over the upper and lower vertebral bodies 3, 3 of the excised disc, and the upper and lower vertebral bodies are provided inside the cylindrical body 501 of the bone prosthetic material 5. Since the facing portions 307 and 307 of the bones 3 and 3 remain, the bone prosthesis 5 can receive the force in the compression tension direction acting on the vertebral bodies 3 and 3 located above and below and the direction orthogonal to the compression tension direction. Therefore, even if a force in the compression tension direction and a force in a direction orthogonal to the compression tension direction act on the upper and lower vertebral bodies 3, 3, the upper and lower vertebral bodies 3, 3 can be stably fixed by the bone prosthetic material 5. it can. In addition, the cylindrical body 5 of the bone filling material 5
01, inside the vertebral bodies 3, 3 facing each other 30
Since 7,307 remains, both remaining parts 30
Bone tissue of 7,307 grows and bone fusion is performed, which is advantageous in stably fixing the upper and lower vertebral bodies 3, 3.

Further, since a large number of holes 505 are formed in the cylindrical body 501 of the bone prosthetic material 5, bone penetrates into the holes 505 and the portion 307 remaining inside the cylindrical body 501 of the bone prosthetic material 5 and the cylindrical body Bone fusion with the vertebral body portion 313 located outside the 501 is performed, whereby the upper and lower vertebral bodies 3, 3 can be more stably fixed. In this case, the cylindrical body 501
Is coated with a calcium phosphate-based compound having excellent biocompatibility, bone tissue easily enters the hole 505, and the portion 307 remaining inside the cylindrical body 501 and the vertebral body portion 313 located outside the cylindrical body 501 It is advantageous for the bone fusion of and.

Further, since the bone filling material 5, the plate 7, and the screw 9 are all formed of a titanium alloy and coated with a calcium phosphate-based compound, the weight can be reduced, and the calcium phosphate-based compound is excellent in bone fusion. Bone fusion between the surfaces of these members 5, 7, 9 and the vertebral body 3 is performed, and the bone prosthetic material 5 can be reliably fixed over the upper and lower vertebral bodies 3, 3.
Further, in the embodiment, since the plate 7 and the screw 9 are used, the strength and the rigidity of the bone prosthetic material 5 are enhanced by these members 7 and 9, and the upper and lower vertebral bodies 3 and 3 are stably fixed. Be advantageous.

FIG. 8 shows a modification of the plate 7. In this modified example, the flange portion 703 is formed in a cylindrical surface according to the shape of the vertebral body 3, and when this plate 71 is used, the end surface of the bone prosthetic material 5 that abuts the flange portion 703 is A cylindrical surface that engages with the flange portion 703 is formed. If such a plate 71 is used, the amount of protrusion of the plate 71 can be reduced and the plate 71 can be arranged in a small space.

It should be noted that the facing portions 3 of the upper and lower vertebral bodies 3, 3
The bone filling material 5 may be embedded between 07 and 307 with a spacer made of, for example, an osteointegrative material or a biocompatible material, inserted. Also, in the example,
The case where the plate 7 and the screw 9 are used in order to fix the bone prosthetic material 5 and enhance the strength and rigidity of the bone prosthetic material 5 has been described, but the plate 7 and the screw 9 may not be used. For example, various methods for fixing the bone prosthetic material 5 are conceivable. The bone prosthetic material 5 may be simply fixed by a screw formed on the outer periphery of the cylindrical body 501, or a flange is formed at the end of the cylindrical body 501. The bone prosthesis material 5 may be fixed by a screw that is inserted through the flange and screwed into the vertebral body 3. Further, without using the plate 7 and the screw 9, by increasing the wall thickness of the cylindrical body 501 or changing the material of the cylindrical body 501,
The strength and rigidity of the bone filling material 5 can be increased. Furthermore,
The bone filling material 5 is not limited to a cylindrical shape, and may be, for example, a hollow rectangular shape. Next, second to fourth embodiments in which a flange is integrally formed at the end of the cylindrical body will be described.

The second embodiment will be described with reference to FIGS. 9 to 11. The bone filling material 21 according to the second embodiment is composed of a cylindrical body 25 and a flange 27 formed at the end of the cylindrical body 25. A screw 2501 is formed on the outer circumference of the cylindrical body 25. As in the first embodiment, the length of the cylindrical body 25 is formed such that the vertebral body portion 311 remains on the spinal cord 1 side in a state of being embedded over the upper and lower vertebral bodies 3, 3. Is provided with a large number of holes 2502 which communicate the inside and the outside of the cylindrical body 25. The cylindrical body 2
A tapered taper surface 2503 is formed at the tip of the outer periphery of 5 so as to be easily embedded in the upper and lower vertebral bodies 3, 3. The flange 27 has a rectangular shape, and screw holes 2701 are formed at four corners of the flange 27.
On both sides of the upper surface of 7, as shown in FIG.
03 is formed. Screw 2 in the screw hole 2701
9 is screwed and the screw 29 is connected to the upper and lower vertebral bodies 3, 3. Bone prosthesis material 21 and screw 29 having the above structure
Is made of a titanium alloy and is not coated with calcium phosphate. In this embodiment, the screw 2501 and the screw 29 correspond to the fixing means.

Next, a procedure for cutting off the intervertebral disc which has become an obstacle and fixing the vertebral bodies 3, 3 located above and below the cut intervertebral disc with the bone filling material 21 will be described. First, an annular groove having a size in which the cylindrical body 25 is fitted is formed over the vertebral bodies 3 and 3 located above and below the intervertebral disc where the intervertebral disc is removed, as in the first embodiment. Next, while rotating the bone filling material 21, the cylindrical body 25 is fitted into the annular groove, and the bone filling material 21 is embedded over both vertebral bodies 3, 3. In this case, an internal thread may be formed in advance in the annular groove, or the cylindrical body 25 may be threaded while being fitted into the annular groove. Then, after the cylindrical body 25 is embedded, small holes having a smaller diameter than the screw hole 2701 are made in the vertebral body portion of the flange 27 that matches the screw hole 2701, and the screw 29 is embedded in the screw hole 2701 and the small hole. The small hole may be formed in advance when the annular groove is formed in the upper and lower vertebral bodies 3, 3.

Also in the second embodiment, as in the first embodiment, the bone filling material 21 is embedded and fixed over the vertebral bodies 3, 3 above and below the excised intervertebral disc, and the bone filling material 2
Since the facing portions of the upper and lower vertebral bodies 3, 3 remain inside the cylindrical body 25 of No. 1, the compressive tension direction acting on the vertically located vertebral bodies 3, 3 and the force in the direction orthogonal to the compressive tension direction are applied. It can be received by the bone filling material 21. In addition, since the facing parts of the upper and lower vertebral bodies 3, 3 remain inside the cylindrical body 25 of the bone prosthesis 21, the bone tissue of both remaining parts grows, and bone fusion is performed. This is advantageous in stably fixing the bodies 3 and 3. In addition, the bone filling material 21
Since a large number of holes 2502 are formed in the cylindrical body 25 of
Bone invades 502, and bone fusion between the vertebral body portion remaining inside the cylindrical body 25 and the vertebral body portion located outside the cylindrical body 25 is performed, and the upper and lower vertebral bodies 3, 3 are stably fixed. It will be advantageous in doing so.

Next, a third embodiment will be described with reference to FIGS. Bone substitute material 31 according to the third embodiment
Is a modification of the second embodiment, and the shape of the flange is different from that of the second embodiment. The bone filling material 31 according to the third embodiment is the second one.
Similar to the embodiment, it is composed of a cylindrical body 35 and a flange 37 formed at the end of the cylindrical body 35.
As described above, the screw 3501, the hole 3502, the tapered surface 3
503 is formed. The flange 37 is a cylindrical body 3
5 are formed so as to project outward in the radial direction of the cylindrical body 35 on both sides of the end portion of 5, and two screw holes 3701 are formed in the flange 37 at positions near the front end thereof. As shown in FIG. A cylindrical surface 3703 is formed from both sides of the upper surface of the cylindrical body 35 to the upper part of the cylindrical body 35. In FIG. 13, reference numeral 3701A indicates the axis of each screw hole 3701, and the screw holes 3701 are screwed into the screw holes 3701 so that the tips of the screws 39 connected to the upper and lower vertebral bodies 3, 3 are separated from each other. It is formed to be inclined. The bone prosthesis material 31 and the screw 39 configured as described above are made of a titanium alloy and are not coated with calcium phosphate. In this embodiment, the screw 3501 and the screw 39 correspond to the fixing means. The third embodiment as described above also achieves the same effects as the second embodiment.

Next, a fourth embodiment will be described with reference to FIGS. Bone substitute material 41 according to the fourth embodiment
Is a modification of the third embodiment, and two flanges are provided in the third embodiment, whereas one flange is provided in the third embodiment. The bone filling material 41 according to the fourth embodiment includes a cylindrical body 45 and a flange 47 formed at an end of the cylindrical body 45.
The cylindrical body 45 is provided with a screw 4 as described above.
501, a hole 4502, and a tapered surface 4503 are formed, and the axis line 4701A is inclined on the flange 47 to form a screw hole 47.
01 is formed and screwed into the screw hole 4701.
9 is connected to the vertebral body 3. Also, as shown in FIG.
A cylindrical surface 4703 is formed from both sides of the upper surface of the flange 47 to the upper part of the cylindrical body 45. Further, as shown in FIG. 16, a cutout 4509 is formed in the end portion of the cylindrical body 45 where the flange 47 is not formed. There is. In this embodiment, the screw 4501 and the screw 49 correspond to the fixing means. The same effect as that of the second embodiment can be obtained by the fourth embodiment.

[0022]

As is apparent from the above description, the bone prosthesis material according to the present invention is embedded over the vertebral bodies located above and below the resected intervertebral disc, and the facing parts of the vertebral bodies located above and below the excised disc are removed. Since it has a hollow member located inside it, when the intervertebral disc that has become an obstacle is resected in spinal diseases such as disc herniation, the vertebral bodies located above and below the excised disc are compressed and stretched in the direction of compression and tension. It becomes possible to stably fix to the force in the direction orthogonal to the direction.

[Brief description of drawings]

FIG. 1 is a sectional side view of a bone filling material according to a first embodiment in a used state.

FIG. 2 is a front view of a bone filling material according to the first embodiment in a used state.

FIG. 3 is a side view of the bone substitute material according to the first embodiment.

FIG. 4 is a cross-sectional side view of the bone prosthetic material according to the first embodiment.

FIG. 5 is a front view of the bone substitute material according to the first embodiment.

FIG. 6 is a front view of a plate.

FIG. 7 is a sectional side view of the plate.

FIG. 8 is a sectional side view of a modification of the plate.

FIG. 9 is a plan view of a bone substitute material according to a second embodiment.

FIG. 10 is a front view of a half section of the bone prosthetic material according to the second embodiment.

FIG. 11 is a side view of the bone prosthetic material according to the second embodiment.

FIG. 12 is a plan view of a bone substitute material according to a third embodiment.

FIG. 13 is a front view of a half section of the bone prosthetic material according to the third embodiment.

FIG. 14 is a side view of the bone prosthetic material according to the third embodiment.

FIG. 15 is a plan view of a bone substitute material according to a fourth embodiment.

FIG. 16 is a half sectional front view of the bone prosthetic material according to the fourth embodiment.

FIG. 17 is a side view of the bone prosthetic material according to the fourth embodiment.

[Explanation of symbols]

 1 Spinal cord 3 Vertebra 5,21,31,41 Bone substitute 7,71 Plate 9,29,39,49 Screw 307 Remaining part of vertebral body

Claims (6)

[Claims] 1. A hollow member, which is embedded over vertebral bodies located above and below a resected intervertebral disc, and in which the facing portions of the vertebral bodies located above and below the excised intervertebral disc are located, and the hollow member. A bone prosthesis material comprising: a fixing means for fixing to a vertebral body. 2. The bone filling material according to claim 1, wherein the hollow member has a cylindrical shape, and the fixing means includes a screw formed on the outer periphery of the hollow member. 3. A flange is provided at an end of the hollow member, and the fixing means includes a screw which is inserted through the flange and is connected to a vertebral body. Bone replacement material. 4. The bone substitute material according to claim 3, wherein the flange is formed integrally with the hollow member. 5. The bone substitute material according to claim 3, wherein the flange is formed separately from the hollow member. 6. The bone substitute material according to claim 1, wherein the hollow member is provided with a large number of holes that communicate the inside and the outside of the hollow member.