阅读说明：本技术 一种多孔结构融合器 (Porous structure fuses ware ) 是由 蔡方舟 丁伟 于 2019-08-26 设计创作，主要内容包括：本发明提供了一种多孔结构融合器,包括：筒状件,以及套设在筒状件上的融合器本体,疏松撑开部,所述疏松撑开部设置在所述筒状件与所述融合器本体之间,用于连接融合器本体和筒状件；其中,疏松撑开部由若干单胞结构阵列连接而成的多孔结构,所述单胞结构由若干微杆连接而成双棱锥结构,本发明通过对现有的融合器本体内部进行改造,有利于成骨细胞的增殖、分化和生长,形成紧密的骨内植入界面,以及单胞结构的填充,使植入后的融合器本体更容易形成紧密的骨痂和骨桥,更有利于骨长入。(The invention provides a porous structure fusion cage, comprising: the fusion cage comprises a cylindrical part, a fusion cage body sleeved on the cylindrical part and a loosening and opening part, wherein the loosening and opening part is arranged between the cylindrical part and the fusion cage body and is used for connecting the fusion cage body and the cylindrical part; the invention improves the interior of the existing fusion cage body, is beneficial to the proliferation, differentiation and growth of osteoblasts, forms a compact intraosseous implantation interface, and fills the single cell structure, so that the implanted fusion cage body can more easily form compact callus and bone bridge, and is more beneficial to bone ingrowth.)

1. A porous structure fusion cage characterized by: comprises that

The fusion cage comprises a cylindrical part and a fusion cage body sleeved on the cylindrical part;

the loosening and opening part is arranged between the cylindrical part and the fusion device body and is used for connecting the fusion device body and the cylindrical part;

the loosening and opening part is of a porous structure formed by connecting a plurality of unit cell structures, and each unit cell structure is of a double-pyramid structure formed by connecting a plurality of micro rods.

2. A multi-cellular structure fusion device according to claim 1 further comprising: further comprising:

and one end of each reinforcing rib is connected to the outer wall of the cylindrical part, and the other end of each reinforcing rib is connected to the inner wall of the fusion device body.

3. A multi-cellular structure fusion device according to claim 1 further comprising: the periphery wall of the barrel-shaped part is provided with at least one first filling hole.

4. A multi-cellular structure fusion device according to claim 3 wherein: the loose opening part extends into the first filling hole and is filled with the first filling hole.

5. A multi-cellular structure fusion device according to claim 1 further comprising: the peripheral wall of the fusion device body is provided with at least one second filling hole.

6. The cellular structure fusion device according to claim 5, wherein: the loose opening part extends into the second filling hole and is filled with the second filling hole.

7. A multi-cellular structure fusion device according to claim 1 further comprising: a plurality of bulges are formed at two ends of the fusion device body.

8. A multi-cellular structure fusion device according to claim 1 further comprising: the fusion cage body is manufactured in an integrated mode and is provided with a first end face and a second end face which are used for being in butt joint with a vertebral body, and the side wall of the fusion cage body of the mounting hole is provided with at least two inclined mounting holes which are respectively inclined towards the first end face and the second end face and used for fixing the fusion cage body on a vertebra.

9. A multi-cellular structure fusion device according to claim 8 further comprising: the two mounting holes respectively form an included angle of 15-25 degrees with the two end surfaces of the fusion cage body.

10. A multi-cellular structure fusion device according to claim 1 further comprising: the micro rod is a straight rod or a bent rod.

Technical Field

The invention relates to the field of medical instruments, in particular to a fusion cage with a porous structure.

Background

Intervertebral joint degeneration and peripheral tissue compression caused by chronic strain are main causes of cervical spondylosis, and a series of cervical nerve root syndromes seriously affect the life of patients. The anterior decompression fusion of cervical spondylosis is the first choice of degenerative cervical spondylosis which is ineffective in conservative treatment, but the titanium alloy fusion cage used in the clinical process at the present stage has higher overall elastic modulus, and is directly applied to the conditions of internal implant deposition, stress shielding and the like which are easily generated between vertebral bodies, so that the solid titanium alloy interbody fusion cage is not suitable for clinical use. At present, titanium alloy implanted into a porous structure is adopted, but a cavity is formed in the middle of a fusion device body of the existing porous structure, so that the fatigue strength of the fusion device is reduced while the elastic modulus is reduced, and the postoperative fusion device fails.

Disclosure of Invention

The invention aims to provide a novel cervical vertebra porous structure fusion cage, which reduces the elastic modulus, ensures the strength of the fusion cage, promotes callus and bone bridges closely connected with bone formation after the fusion cage is implanted, and effectively promotes bone growth.

The technical scheme provided by the invention is as follows: a multi-cellular structure cage, comprising:

the fusion cage comprises a cylindrical part and a fusion cage body sleeved on the cylindrical part;

the loosening and opening part is arranged between the cylindrical part and the fusion device body and is used for connecting the fusion device body and the cylindrical part;

the loosening and opening part is of a porous structure formed by connecting a plurality of single-cell structures in an array mode, and the single-cell structures are of a double-pyramid structure formed by connecting a plurality of micro rods.

In this technical scheme, through reforming transform inside the present fusion cage body, strut the partial connection tube-shape spare and fusion cage body through the looseness, form the internal frame, reduce the elastic modulus of fusion cage itself, be difficult to produce the implant deposit, the circumstances such as "stress shielding" are favorable to osteoblast's proliferation, differentiation and growth, form inseparable intraosseous implantation interface, and the filling of loose division portion of strutting, make the fusion cage body after the implantation form inseparable callus and bone bridge more easily, more be favorable to the bone to grow into.

Preferably, the method further comprises the following steps: and one end of each reinforcing rib is connected to the outer wall of the cylindrical part, and the other end of each reinforcing rib is connected to the inner wall of the fusion device body.

In this technical scheme, through set up the strengthening rib between tube-shape spare and fuse the ware body, guaranteed the bearing capacity that fuses the ware, when guaranteeing inside porous structure, the inside intensity of reinforcing fusion ware.

Preferably, the outer peripheral wall of the cylindrical member is opened with at least one first filling hole.

In the technical scheme, the first filling hole is formed in the cylindrical part, so that the first filling hole is favorable for cell adhesion growth, extracellular matrix deposition, nutrition and oxygen entry and metabolite discharge, and is also favorable for growth of blood vessels and nerves.

Preferably, the loose spreader extends into and fills the first fill hole.

In the technical scheme, the loose opening part extends into the first filling hole and is filled with the first filling hole, so that the space in the first filling hole is further changed, a multistage pore structure is formed, the porous structure is favorable for cell adhesion growth, extracellular matrix deposition, nutrition and oxygen entry and metabolite discharge, and is also favorable for blood vessels and nerves to grow in, and the fusion cage is an ideal fusion cage structure. In particular to intra-osseous implants, the porous structure facilitates the growth of osteoblasts into the pores and the production of a bony component. On the other hand, the surface roughness of the porous internal implant is controllable, which is beneficial to the adhesion and growth of bone cells. Finally, the well-designed porous structure is beneficial to reducing the elastic modulus of the solid internal implant and avoiding the stress shielding effect of the fusion between the vertebral bodies.

Preferably, the fusion cage body is provided with at least one second filling hole on the peripheral wall.

In the technical scheme, the second filling hole is formed in the peripheral wall of the fusion cage body, so that the second filling hole is favorable for cell adhesion growth, extracellular matrix deposition, nutrition and oxygen entry and metabolite discharge, and is also favorable for growth of blood vessels and nerves.

Preferably, the loose spreader portion extends into and fills the second fill hole.

In the technical scheme, the loose opening part extends into the second filling hole and is filled with the second filling hole, so that the space in the second filling hole is further changed, a multistage pore structure is formed, the porous structure is favorable for cell adhesion growth, extracellular matrix deposition, nutrition and oxygen entry and metabolite discharge, and is also favorable for blood vessels and nerves to grow in, and the fusion cage is an ideal fusion cage structure. In particular to intra-osseous implants, the porous structure facilitates the growth of osteoblasts into the pores and the production of a bony component. On the other hand, the surface roughness of the porous internal implant is controllable, which is beneficial to the adhesion and growth of bone cells. Finally, the well-designed porous structure is beneficial to reducing the elastic modulus of the solid internal implant and avoiding the stress shielding effect of the fusion between the vertebral bodies.

Preferably, a plurality of protrusions are formed at both ends of the cage body.

In this technical scheme, the both ends of fusing the ware body have been seted up protrudingly for fuse the ware when implanting, can make fusing ware body both ends and cervical vertebra bone laminating better, promote the stability of being connected of fusing ware and centrum.

Preferably, the fusion cage body is manufactured in an integral molding mode and is provided with a first end face and a second end face which are used for being in butt joint with a vertebral body, and the side wall of the fusion cage body of the mounting hole is provided with at least two inclined mounting holes which are respectively inclined towards the first end face and the second end face and used for fixing the fusion cage body on a vertebra.

In the technical scheme, the two mounting holes are formed, so that the fusion cage can be fixed on the upper bone and the lower bone of the cervical vertebra through screws when being implanted, and the stability of the fusion cage is improved.

Preferably, the two mounting holes respectively form an included angle of 15-25 degrees with the two end faces of the fusion cage body.

Preferably, the micro-rods are straight rods or bent rods.

Compared with the prior art, the porous structure fusion cage provided by the invention has the following beneficial effects:

1. according to the invention, the interior of the existing fusion cage body is modified, the cylindrical part and the loose part are additionally arranged to connect the cylindrical part and the fusion cage body, so that the fusion cage body further forms an inner frame, the elastic modulus of the fusion cage is reduced, the deposition of an implant is not easy to generate, the conditions of stress shielding and the like are facilitated, the proliferation, differentiation and growth of osteoblasts are facilitated, a compact intraosseous implantation interface is formed, and the implanted fusion cage body is more easily formed into compact callus and bone bridges by filling a single cell structure, and is more beneficial to bone ingrowth.

2. The porous structure is favorable for cell adhesion growth, extracellular matrix deposition, nutrition and oxygen entry and metabolite discharge, and is also favorable for blood vessel and nerve growth, so that the fusion cage is an ideal fusion cage structure. Particularly, the porous structure of the implant in the bone is beneficial to the growth of osteoblasts into pores and the generation of bone components, and on the other hand, the surface roughness of the implant in the bone is controllable, thereby being beneficial to the adhesion and the growth of the osteoblasts. Finally, the porous structure is beneficial to reducing the elastic modulus of solid internal implants and avoiding the stress shielding effect of the fusion between the vertebral bodies.

Drawings

The above features, technical features, advantages and modes of realisation of a multi-cellular structure fusion device will be further described in the following, in a clearly understandable manner, with reference to the accompanying drawings, which illustrate preferred embodiments.

FIG. 1 is a schematic top view of the present invention;

FIG. 2 is a schematic structural diagram of another embodiment of the present invention;

FIG. 3 is a schematic perspective view of the unfilled loose spreader portion of FIG. 2;

FIG. 4 is a schematic structural diagram of another embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another embodiment of the present invention;

FIG. 6 is a schematic view of a further perspective of the unfilled loose expansion of FIG. 5;

FIG. 7 is a schematic view of the alternate view structure of FIG. 6;

FIG. 8 is a schematic view of a further perspective structure of FIG. 6;

FIG. 9 is a schematic diagram of a unit cell structure;

FIG. 10 is a schematic diagram of a simulation of a unit cell structure;

FIG. 11 is a schematic diagram of an application of the cage of FIG. 4;

FIG. 12 is a schematic representation of the reconstruction after 6 weeks of sample MicroCT scan;

FIG. 13 is a schematic representation of the reconstruction after a 12 week sample MicroCT scan;

FIG. 14 is a schematic representation of the reconstruction after a 24 week sample MicroCT scan;

FIG. 15 is a schematic representation of hard tissue sections from 6 week, 12 week, 24 week samples;

FIG. 16 is a graph of broken lines showing the percent bone in growth at different time nodes for the 6 week, 12 week, 24 week samples;

fig. 17 is a broken line graph of bone density at different time nodes for the 6 week, 12 week, 24 week samples.

The reference numbers illustrate: the cage comprises a cylinder 100, a first filling hole 101, a cage body 200, a front wall 201, a rear wall 202, a protrusion 203, a mounting hole 204, a second filling hole 205, a reinforcing rib 3 and a loosening and expanding part 4.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will be made with reference to the accompanying drawings. It is obvious that the drawings in the following description are only some examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be derived from them without inventive effort.

For the sake of simplicity, the drawings only schematically show the parts relevant to the present invention, and they do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled. In this document, "one" means not only "only one" but also a case of "more than one".

According to an embodiment of the present invention, a multi-hole structure fusion cage, as shown in fig. 1 and 4, includes: a barrel 100, and a cage body 200 fitted over the barrel 100; a loosening and spreading part 4, the loosening and spreading part 4 being provided between the cylindrical member 100 and the fusion cage body 200 for connecting the fusion cage body and the cylindrical member 100; the loosening and expanding part 4 is a porous structure formed by connecting a plurality of unit cell structures, as shown in fig. 9, the unit cell structure is a double pyramid structure formed by connecting a plurality of micro-rods, and in the specific implementation, the double pyramid structure is manufactured by a 3D printing technology, so that the cylindrical part 100, the loosening and expanding part 4 and the fusion device body 200 are integrated; the loose portion 4 that struts is connected with tube-shape piece 100, forms inside frame, for fusing ware body 200 provides internal support structure, makes and fuses ware body 200 can also increase strength when reducing elastic modulus, and the single cell structure that a plurality of micro-rods formed of connecting has fine pore structure, is favorable to fusing the callus and the bone bridge that the ware body was implanted and is closely related with the bone formation, does benefit to the growth of bone and goes into.

In this embodiment, the fusion cage body 200, the tubular member 100 and the unit cell structure are made of titanium alloy material instead of the conventional PEEK (polyether ether ketone) material, and when the PEEK material is used, the PEEK material cannot be tightly combined with the surrounding bone tissue, and a small gap exists between the bone interface and the implant interface, which may cause the fusion cage to loosen or even fail to fuse; on the other hand, when the PEEK fusion cage is used, autologous or allogeneic bones need to be implanted;

the titanium alloy material is adopted in the invention, and the problem of the porous structure of the material can be well solved through an additive manufacturing technology, namely a 3D printing technology. The 3D printing technology enables an inner framework and an outer framework of an entity to be obtained, the middle of the inner framework is hollow, the weight is reduced, the elastic modulus is reduced, the overall performance of the whole implant is closer to the material property of human bones, the 3D printing porous structure titanium alloy embedded object has better animal safety and tolerance, callus and bone bridges closely connected with bone formation are facilitated after the implant is implanted, and meanwhile, the bone growth in pores is obvious. The design of this structure can make the fusion cage form 300 um's non-hollow structure, is favorable to the income of bone more, sees from fig. 12-14, 300 um's hole, compares with 600 um's hole at same time point, and its inside new bone is more.

The inner part of the existing fusion cage body 200 is modified, the cylindrical part 100 and the loose opening part 4 connected with the cylindrical part 100 are increased to form an inner frame 1, the inner frame 1 bears axial load, the strength of the fusion cage is improved, compared with the whole titanium alloy fusion cage, the elastic modulus of the fusion cage is reduced, the deposition of an implant is not easy to generate, the conditions of stress shielding and the like are reduced, the proliferation, differentiation and growth of osteoblasts are facilitated, a compact intraosseous implantation interface is formed, and the implanted fusion cage body is more easily formed into compact callus and bone bridges by filling of a single cell structure, so that the bone can grow in;

in the embodiment shown in fig. 10, the unit cell structure formed by the micro-rods is formed by connecting straight rods or curved rods at the central points of two adjacent surfaces of the inner wall of the cube. In the technical scheme, the square body is preferably connected by curved bent rods, when the side length of the square body is L, the R is 0.45 times of the side length, when the R is infinite, the R is a straight line, the bent rods form double rectangular pyramids, certain variable spaces exist in the bent rods, the toughness of a porous structure can be increased and the elastic modulus of a product can be reduced besides the shape of the double rectangular pyramids, the straight rods only depend on the structural deformation of the double rectangular pyramids to reduce the elastic modulus of the product, and the formed double rectangular pyramids enable the pore levels to be more, so that the growth of bones is facilitated.

In another embodiment of the present invention, as shown in fig. 2 and 5, at least two reinforcing ribs 3 are provided, one end of each reinforcing rib 3 is connected to the outer wall of the cylindrical member 100, the other end of each reinforcing rib 3 is connected to the inner wall of the cage body 200, and a plurality of protrusions 203 are formed at both ends of the cage body 200.

In this embodiment, mode that strengthening rib 3 and arch 203 used 3D to print and whole integration ware body 200 to form integratively equally, and strengthening rib 3 can guarantee to merge the ware when increasing porous structure, can also strengthen inside intensity, and arch 203 can make integration ware body both ends and the laminating of cervical vertebra bone better when merging the ware and implant, is difficult for removing.

In another embodiment of the present invention, as shown in fig. 3 and 6, the outer peripheral wall of the cylindrical member 100 is provided with at least one first filling hole 101, and the loose opening part 4 extends into the first filling hole 101 and fills the first filling hole 101; the peripheral wall of the fusion cage body 200 is provided with at least one second filling hole 205, and the loose opening part 4 extends into the second filling hole 205 and fills the second filling hole 205.

In this embodiment, the first filling hole 101 is formed in the cylindrical member 100, the second filling hole 205 is formed in the circumferential wall of the fusion body 200, then the loose opening part 4 formed by a unit cell structure is filled in the first filling hole 101 and the second filling hole 205, and the loose opening part 4 is arranged between the cylindrical member 100 and the fusion body 200, so that the whole fusion device body forms a porous structure, and the porous structure is favorable for cell adhesion growth, extracellular matrix deposition, nutrient and oxygen entry, metabolite discharge, and vascular and nerve ingrowth, and is an ideal titanium alloy structure. The well-designed porous structure is beneficial to reducing the elastic modulus of solid internal implants and avoiding the stress shielding effect of the fusion between vertebral bodies. Solves the problems of the operation of planting autogenous bone or allogeneic bone and the risk of rejection in the prior operation. The fusion cage solves the effect that the upper and lower segments can still be fused under the condition of no bone grafting.

In another embodiment of the present invention, as shown in fig. 7 and 8, the fusion cage body 200 is integrally formed and has a first end surface and a second end surface for abutting against a vertebral body, and the side wall of the fusion cage body 200 of the mounting hole 204 is provided with at least two inclined mounting holes 204 inclined to the first end surface and the second end surface respectively for fixing the fusion cage body 200 on a vertebra, in a specific implementation, the fusion cage body 200 is integrally formed by a front wall 201 and an opposite rear wall 202, the front wall 201 is provided with two inclined mounting holes 204, the two mounting holes 204 are inclined to the two end surfaces respectively, and the two mounting holes 204 form an included angle of 15-25 degrees with the two end surfaces of the fusion cage body 200 respectively.

In this embodiment, the fusion cage is implanted between the upper and lower bones of the cervical vertebrae by forming the mounting holes 204, and then fixed to the upper and lower bones through the mounting holes 204 by medical fixing screws, respectively, to ensure a good fixing effect.

Experiments prove that the PEEK fusion cage, the titanium alloy solid fusion cage and the cervical vertebra fusion cage with the porous structure printed by the titanium alloy have the elastic modulus and the bone ingrowth effect.

1. Modulus of elasticity: n/mm

Titanium alloy solid fusion device	PEEK fuses ware	The invention relates to a fusion device	Human bone
				66593.3	22460.67	18901	12000

The experimental data comparison shows that the elastic modulus in the application file is obviously close to that of human bones, and the biocompatibility is good.

2. Bone ingrowth condition:

through animal experiments, the solid structure and the surface have no bone growth and attachment.

The titanium alloy microporous structure was obtained by CT scanning, bone in-growth reached about 25% at 6 weeks, and the bone in-growth rate increased with the passage of time. Reaching about 50% at 24 weeks. Bone density also exhibits the same characteristics. Over time, the density of new bone cortical bone is approaching the density of osteogenic bone. The hard slices corroborate the CT conclusion.

The CT reconstruction results are shown in fig. 12-14.

The hard cut results were as follows:

hard tissue sections were sliced by using an EXAKT E300 microtome and an EXAKT E400 CP microtome, and the results are shown in FIG. 15 (cutting tools and techniques: diamond band saw, point contact cutting, cutting speed: 10000mm/sec, minimum thickness of cut sample: 30um, sample size range: 100 mm. times.90 mm. times.60 mm, constant temperature control: circulating cooling water, grinding force: grinding force controlled by an electronic measurement system, minimum force of 1N, sample thickness after grinding: 5-20 μm).

As shown in FIGS. 16-17, over time of implantation, there was no significant difference in BV/TV and BMD for S-600, H-600, S-300, H-300; however, as time goes on, H-300 is obviously increased on both BV/TV and BMD indexes, which indicates that the area of bone ingrowth is increased and that the difference has statistical significance.

It should be noted that the above embodiments can be freely combined as necessary. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.