阅读说明：本技术 一种寰枢椎侧块关节融合器 (Atlantoaxial lateral mass joint fusion cage ) 是由 余新光 郝世杰 宗睿 万明 杜宝鹏 于 2019-11-21 设计创作，主要内容包括：本发明公开一种寰枢椎侧块关节融合器,该融合器具有在温度20摄氏度以上的第一结构,以及在0至8摄氏度时的第二结构,所述第二结构由所述第一结构在同一个方向下压缩而成,所述第二结构状态下温度升高到20摄氏度以上时可恢复为所述第一结构,且所述第一结构和所述第二结构的外部轮廓均为多面体或曲面体形状结构。这种融合器从寰枢椎侧块关节的后方进行植入,植入时不需要很大的操作空间,操作简便,对关节及其周围结构损伤小,并且复位效果好,可以显著改善手术疗效。(The invention discloses an atlantoaxial lateral mass joint fusion cage which is provided with a first structure at the temperature of more than 20 ℃ and a second structure at the temperature of 0-8 ℃, wherein the second structure is formed by compressing the first structure in the same direction, the second structure can be restored to the first structure when the temperature is increased to more than 20 ℃ in the state of the second structure, and the outer outlines of the first structure and the second structure are both polyhedral or curved surface shape structures. The fusion cage is implanted from the back of the atlantoaxial lateral mass joint, does not need a large operation space during implantation, is simple and convenient to operate, has small damage to the joint and the surrounding structure thereof, has good reduction effect, and can obviously improve the operation curative effect.)

1. The atlantoaxial lateral mass joint fusion cage is characterized by comprising a first structure and a second structure, wherein the first structure is at a temperature of more than 20 ℃, the second structure is at a temperature of 0-8 ℃, the second structure is formed by compressing the first structure in the same direction, and the second structure can be restored to the first structure when the temperature is increased to more than 20 ℃ under the state of the second structure;

the outer contours of the first structure and the second structure are both polyhedral or curved surface shape structures.

2. The atlantoaxial lateral mass arthrodesis cage of claim 1, wherein the arthrodesis cage is a single structural member and the first structure has an internal structure of interconnected honeycomb or mesh structure.

3. The atlantoaxial lateral mass arthrodesis fusion cage of claim 1, wherein the arthrodesis fusion cage is made of nickel titanium shape memory alloy, wherein the mass percentage of nickel is 45% -60%.

4. The atlantoaxial lateral mass fusion cage of claim 1, wherein the first structure is defined by an anterior wall, a posterior wall, a left side wall, a right side wall, an upper surface and a lower surface, wherein the anterior wall is opposite the posterior wall, the left side wall is opposite the right side wall, the upper surface is opposite the lower surface, and the second structure is formed by compressing the first structure in an up-down direction.

5. The atlantoaxial lateral mass fusion cage of claim 4, wherein the anterior wall is an anteriorly convex arc, the anterior wall remaining anteriorly convex in the second compressed configuration.

6. The atlantoaxial lateral mass arthrodesis fusion cage of claim 4, wherein the superior surface is an upwardly convex arc surface configuration, and wherein in the second compressed configuration, the superior surface is a planar configuration and is parallel to the inferior surface.

7. The atlantoaxial lateral mass fusion cage of claim 4, wherein the left lateral wall is parallel to the right lateral wall and the lower surface is perpendicular to the left and right lateral walls, the anterior wall having a height greater than the posterior wall.

8. The atlantoaxial lateral mass arthrodesis device as claimed in any one of claims 4 to 7, wherein the arthrodesis device is a single structural member, and the first structure is a honeycomb or net structure, and the upper surface and the lower surface of the first structure are provided with first through holes which are vertically communicated, and the first through holes are communicated with the pores of the honeycomb or net structure.

9. The atlantoaxial lateral mass arthrodesis device of claim 8, wherein under the first configuration, the arthrodesis device further comprises a second through hole disposed on the posterior wall, the second through hole is a through hole which is axial in the anterior-posterior direction and which is through with the first through hole.

10. The atlantoaxial lateral mass fusion cage of claim 8, wherein the shape and size parameters of the fusion cage are preset according to different bone shape and size requirements, and the fusion cage is integrally formed by 3D printing.

Technical Field

The invention relates to the technical field of medical instruments, in particular to an atlantoaxial lateral mass joint fusion cage.

Background

The dislocation of the atlas refers to the pathological change of joint dysfunction and nerve compression caused by the loss of normal involution relationship between the atlas and the axis bone joint surface due to congenital development deformity, trauma, tumor, rheumatoid arthritis and other factors. Atlantoaxial dislocation can be classified into recoverable dislocation, refractory dislocation and nonreversible dislocation according to repositionability, wherein the treatment of refractory dislocation is a difficult point and is a hotspot of research in recent years. The classic treatment mode of difficult renaturation atlantoaxial dislocation is to adopt the grinding of the oral dentate process of the anterior way, and the peripheral ligament of the oral dentate process which evolves afterwards is loosened and is assisted with the occipital neck or atlantoaxial fixation of the posterior way, but with the development of reduction technology and internal fixation technology, the effect of decompression, reduction and fixation can be achieved by a single posterior way operation, and the mode becomes the current mainstream operation mode.

The atlantoaxial lateral mass joint is a bearing joint between atlantoaxial and plays an important role in promoting the structural variation of the atlantoaxial lateral mass joint in the occurrence process of congenital atlantoaxial dislocation. Therefore, as the degree of understanding of the disease increases, the focus of the refractory atlantoaxial dislocation treatment gradually shifts to the atlantoaxial lateral mass joint. Implant autologous ilium or fuse the ware in atlantoaxial lateral mass joint, can play the bearing effect and guarantee the stability of atlantoaxial lateral mass joint, can realize the reduction of vertical direction simultaneously, can also cooperate other apparatus to reach better effect of restoreing in addition. However, the atlantoaxial side mass of a patient with difficult renaturation atlantoaxial dislocation slips forwards and downwards compared with the epistropheus side mass, the atlantoaxial side mass joint is in a forward-leaning state, and the existing fusion device can not correct forward leaning of the joint well, or has large required operation space, complex operation and great damage to the joint and surrounding structures.

Therefore, how to provide a fusion cage with better adaptability is a technical problem that needs to be solved urgently by those skilled in the art.

Disclosure of Invention

In order to solve one of the technical problems, the invention provides the atlantoaxial lateral mass joint fusion cage which is implanted from the back of the atlantoaxial lateral mass joint, does not need a large operation space during implantation, is simple and convenient to operate, has small damage to the joint and surrounding structures, has a good resetting effect, and can obviously improve the operation curative effect.

The atlantoaxial lateral mass joint fusion cage is realized by the following technical scheme, and has a first structure with the temperature of more than 20 ℃ and a second structure with the temperature of 0-8 ℃, wherein the second structure is formed by compressing the first structure in the same direction, the atlantoaxial lateral mass joint fusion cage can be restored to the first structure when the temperature of the second structure is increased to more than 20 ℃, and the outer outlines of the first structure and the second structure are both polyhedral or curved surface shape structures.

Because the atlantoaxial lateral mass joint fusion cage provided by the invention can respectively maintain a structural state at two different temperatures, the normal body temperature of a human is about 37 ℃, so the state of the fusion cage above 20 ℃ can be regarded as a natural state by utilizing the characteristic of the fusion cage, and after the fusion cage is produced and manufactured, the atlantoaxial lateral mass joint is kept after being compressed in the same direction (such as up-down direction) by applying external force to the atlantoaxial lateral mass joint in a relatively low temperature state (0-8 ℃), namely, the atlantoaxial lateral mass joint is flattened, so that the atlantoaxial lateral mass joint can be implanted in a small volume during the operation, therefore, the fusion device can be implanted from the rear of the atlantoaxial lateral mass joint, does not need a large operation space and pry off the joint during implantation, has simple and convenient operation, has little damage to the joint and the surrounding structure, has good reduction effect and can obviously improve the curative effect of the operation.

On the basis of the technical scheme, the invention can also have the following further improvement scheme.

Further, the arthrodesis device is a single structural member, and the internal structure of the first structure is a mutually communicated honeycomb or net structure.

Further, the joint fusion device is made of nickel-titanium shape memory alloy, wherein the mass percent of nickel is 45% -60%.

Further, first structure is enclosed by antetheca, back wall, left side wall, right side wall, upper surface and lower surface and becomes, wherein, the antetheca with the back wall is relative, the left side wall with the right side wall is relative, the upper surface with the lower surface is relative, the second structure is for following form after the upper and lower direction compression of first structure.

Further, the front wall is a forward convex cambered surface structure, and in the compressed second structure, the front wall still keeps a forward convex shape.

Furthermore, the upper surface is an arc surface structure protruding upwards, and in the compressed second structure, the upper surface is a plane structure and is parallel to the lower surface.

Further characterized in that the left side wall is parallel to the right side wall and the lower surface is perpendicular to the left and right side walls, the height of the front wall being greater than the height of the rear wall.

Further, the joint fusion cage is a single structural member, the first structure is a honeycomb or net-shaped structure, first through holes which are vertically communicated are formed in the upper surface and the lower surface of the first structure, and the first through holes are communicated with the pores of the honeycomb or net-shaped structure.

Further, under the first structure, the joint fusion cage further comprises a second through hole arranged on the rear wall, and the second through hole is a through hole which takes the front-back direction as the axial direction and is communicated with the first through hole.

Furthermore, the shape and size parameters of the joint fusion cage are preset according to different bone shape and size requirements, and the joint fusion cage is integrally formed by 3D printing.

Particularly, the atlantoaxial lateral mass joint fusion cage provided by the invention has the following beneficial effects in combination with a further improved scheme:

(1) the atlantoaxial lateral mass joint fusion cage provided by the invention is made of nickel-titanium alloy. The nickel-titanium alloy is widely applied to internal fixation of limb fracture, has good biocompatibility, the mechanical strength of the nickel-titanium alloy is close to that of medical titanium alloy, but the elastic modulus is only 1/2 of the medical titanium alloy, and the design of the cellular or reticular structure porous structure further reduces the elastic modulus of the fusion cage, is closer to that of human bones, has lower stress shielding effect, and provides a good biological environment for bone fusion. The nickel-titanium alloy has super elasticity, can generate continuous restoring force after being implanted, plays a role in elastic fixation and increases the instant stability of the implantation of the fusion device.

(2) The atlantoaxial side block joint fusion cage provided by the invention can form different structure shape memory in two temperature states, so that the shape memory effect can be utilized to be reshaped along with the temperature rise after the atlantoaxial side block joint fusion cage is implanted, the volume is small during the implantation, the implantation is convenient, the atlantoaxial side block joint does not need to be pried, the damage to the surrounding structure is small, and the original stability of the joint is kept to the maximum extent.

(3) The atlantoaxial lateral mass joint fusion device provided by the invention is made of nickel-titanium alloy, the atlantoaxial lateral mass joint fusion device is reshaped along with the temperature rise after being implanted by utilizing the shape memory effect, the restoring force generated in the reshaping process is utilized to prop open the atlantoaxial lateral mass joint, and the height of the reshaped front wall is higher than that of the rear wall, so that the dentate process of the axis is displaced towards the front lower part, and the restoration in the vertical and horizontal directions is simultaneously completed, thereby achieving better restoration effect by simpler restoration operation. For the case of large anteversion angle of the atlantoaxial lateral mass joint, the fusion cage can also be used as a fulcrum to be matched with a nail-rod system to achieve greater reduction.

(4) The invention adopts the bionic design concept, the fusion cage is in a first structure along with the change of temperature after being implanted, the upper surface of the fusion cage is in an integrally convex arc-shaped curved surface under the structure and is matched with the shape of the joint surface under the lateral mass of the atlas, and meanwhile, the structure is in a honeycomb or net-shaped structure, and the surface of the fusion cage is in a grid shape and is uneven, so that the fusion cage has better supporting and stabilizing effects. In addition, because the interior of the fusion cage is filled with the honeycomb or net-shaped structure, the fusion cage is provided with a plurality of mutually communicated pores which are communicated with the first through hole and the second through hole, and bone tissues can grow into the interior of the fusion cage through the pores, thereby achieving better fusion effect.

(5) The atlantoaxial lateral mass joint fusion cage is manufactured by 3D printing, and the length, the width, the height, the upper surface curvature, the included angle between the front wall and the rear wall and other appearance parameters and the internal structure parameters such as the aperture, the porosity and the like of the fusion cage can be customized according to the atlantoaxial lateral mass joint form of a patient, so that the optimal resetting, supporting and fusion effects can be achieved.

Drawings

FIG. 1 is a schematic perspective configuration view of the first structure of an embodiment of the atlantoaxial lateral mass fusion cage disclosed in the present invention;

FIG. 2 is a schematic view of another angular perspective configuration of the first configuration of an embodiment of the atlantoaxial lateral mass fusion cage disclosed herein;

FIG. 3 is a bottom side view of the first construct of an embodiment of the atlantoaxial lateral mass fusion cage of the present disclosure;

FIG. 4 is a schematic perspective configuration view of the second construct of an embodiment of the atlantoaxial lateral mass fusion cage disclosed in the present invention;

FIG. 5 is a schematic view of the meshwork of the atlantoaxial lateral mass joint fusion cage disclosed in the present invention;

FIG. 6 is a schematic structural view of a specific embodiment of the mesh unit of the atlantoaxial lateral mass joint fusion cage disclosed in the present invention;

wherein the part numbers in the figures are represented as:

1. front wall, 2, rear wall, 3, left side wall, 4, right side wall, 5, upper surface, 6, lower surface, 7, first through hole, 8, second through hole, 9, mesh unit, 100, first structure, 200, second structure.

Detailed Description

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings. The principles and features of the present invention are described below in conjunction with the drawings, it being noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict. The examples are given solely for the purpose of illustration and are not intended to limit the scope of the invention.

Referring to fig. 1 to 6, fig. 1 is a schematic perspective outline structure of the first structure of an embodiment of the atlantoaxial lateral mass joint fusion cage disclosed in the present invention; FIG. 2 is a schematic view of another angular perspective configuration of the first configuration of an embodiment of the atlantoaxial lateral mass fusion cage disclosed herein; FIG. 3 is a bottom side view of the first construct of an embodiment of the atlantoaxial lateral mass fusion cage of the present disclosure; FIG. 4 is a schematic perspective configuration view of the second construct of an embodiment of the atlantoaxial lateral mass fusion cage disclosed in the present invention; FIG. 5 is a schematic view of the meshwork of the atlantoaxial lateral mass joint fusion cage disclosed in the present invention; fig. 6 is a schematic structural diagram of a specific embodiment of the mesh unit 9 of the atlantoaxial lateral mass joint fusion cage disclosed in the present invention.

It should be noted that, in order to clearly show the outline structure of the atlantoaxial lateral mass fusion cage provided by the present invention, the outline structure is shown in a wire frame mode in fig. 1 to 4, which is not an actual structure.

Referring to fig. 1 to 6, in an embodiment of the atlantoaxial lateral mass joint fusion device provided by the present invention, the joint fusion device has a first structure 100 at a temperature above 20 degrees celsius, which may be referred to as an austenite phase structure in a high temperature state; and a second structure 200 at 0 to 8 degrees celsius, which may be referred to as a martensite phase structure in a low temperature state; it is to be understood that references herein to high and low temperatures are intended to be relative concepts, not absolute. The second structure 200 is formed by compressing the first structure 100 in the same direction, and the second structure 200 can be restored to the first structure 100 when the temperature is increased to more than 20 ℃ in the state of the second structure 200; the outer contours of the first structure 100 and the second structure 200 are both polyhedral or curved structures. In this embodiment, the joint fusion cage has a characteristic of being able to respectively maintain a fixed shape in two temperature ranges, and by using this characteristic, the fusion cage can be compressed and refrigerated at a low temperature, and the normal body temperature of a person is about 37 degrees centigrade, so that by using the fusion cage provided by the present invention, the fusion cage can be reshaped at a temperature above 20 degrees centigrade, where 20 degrees centigrade means that when the temperature of the fusion cage in the compressed second structure is gradually increased to a certain temperature above 20 degrees centigrade, the phase change can occur, and this temperature can be a critical point, for example, 30 degrees centigrade, when reaching 30 degrees centigrade, the fusion cage starts to gradually rebound, and gradually returns to the state of the first structure 100 along with the maintenance or continuous increase of the temperature; the critical point temperature value is related to the material, processing and manufacturing precision, post-processing and the like of the fusion device, and the temperature value of 30-35 ℃ is preferably used as the critical point temperature value. The restored fusion cage can play a role in supporting the joint due to the increase of the height, so that the atlantoaxial joint can be restored. In addition, the compressed fusion cage is in a flat state, is more suitable for being implanted from the back of the atlantoaxial lateral mass joint, does not need a large operation space and pry off the joint during implantation, is simple and convenient to operate, has small damage to the joint and surrounding structures, has a good resetting effect, and can obviously improve the operation curative effect.

The atlantoaxial joint fusion cage provided by the present invention is a single structural member, and the internal structure of the first structure 100 is a mutually communicated honeycomb or net structure. The single structural member is an integral structure of the whole fusion cage, and only has a single structural member without assistance or cooperation of other parts. Therefore, the difficulty and the cost of processing and manufacturing are greatly reduced, and the uniform release of the internal stress is more favorable, so that the atlantoaxial lateral mass joint is more favorably supported and fused with the bone. Meanwhile, the whole structure is of a honeycomb or net structure, a plurality of mutually communicated pores are formed inside the structure, so that the elastic modulus of the fusion cage can be reduced, the elastic modulus of the fusion cage is closer to that of human bones, stress shielding is reduced, and meanwhile, the honeycomb or net structure can be favorable for bone tissues to grow into the fusion cage through the pores, so that a better fusion effect is achieved.

Shape memory alloys transition between two crystalline states, austenite and martensite. At low temperatures, they exhibit martensite which is relatively soft, plastic and easily shaped; at (relatively) high temperatures, they become harder and more difficult to deform austenite.

The joint fusion device is made of nickel-titanium shape memory alloy, wherein the mass percent of nickel is 45% -60%, preferably 50% -55%. Nitinol in this ratio range can have a significant effect on the critical point temperature as described above, and thus can improve the therapeutic effect of the fusion device.

The nickel-titanium alloy is widely applied to internal fixation of limb fracture, has good biocompatibility, the mechanical strength of the nickel-titanium alloy is close to that of medical titanium alloy, but the elastic modulus of the nickel-titanium alloy is only 1/2 of medical titanium alloy, and the design of the honeycomb porous structure enables the elastic modulus of the fusion cage to be further reduced, is closer to that of human bones, has lower stress shielding effect, and provides a good biological environment for bone fusion. The nickel-titanium alloy has shape memory effect, is reshaped along with the temperature rise after being implanted, and can prop open the atlantoaxial lateral mass joint by utilizing the restoring force generated in the reshaping process to achieve the resetting effect. The nickel-titanium alloy has super elasticity, can generate continuous restoring force after being implanted, plays a role in elastic fixation and increases the instant stability of the implantation of the fusion device.

In order to facilitate implantation, according to the structural characteristics of the atlantoaxial joint of a human body, the invention provides an atlantoaxial lateral mass joint fusion cage printed by using a nickel-titanium shape memory alloy material in a 3D mode based on a bionic design concept, and the atlantoaxial lateral mass joint fusion cage has two shape structures, namely a first structure 100 of an austenite phase at a high temperature and a second structure 200 of a martensite phase at a low temperature. The first structure 100 is defined by a front wall 1, a rear wall 2, a left side wall 3, a right side wall 4, an upper surface 5 and a lower surface 6, wherein the front wall 1 is opposite to the rear wall 2, the left side wall 3 is opposite to the right side wall 4, the upper surface 5 is opposite to the lower surface 6, and the second structure 200 is formed by compressing along the vertical direction of the first structure 100. The front wall 1 is a cambered surface structure protruding forwards, and in the compressed second structure 200, the front wall 1 still keeps protruding forwards and is in a circular arc shape, so that the front wall is convenient to implant forwards from the back of a human body. In the state of the first structure 100, the upper surface 5 is an arc surface structure protruding upward, and in the compressed second structure 200, the upper surface 5 is a plane structure and is parallel to the lower surface 6. In the state of the first structure 100, the left side wall 3 is parallel to the right side wall 4, the lower surface 6 is perpendicular to the left side wall 3 and the right side wall 4, and the height of the front wall 1 is greater than the height of the rear wall 2.

In the state of the first structure 100, the upper surface 5 and the lower surface 6 are provided with first through holes 7 which are vertically through, and are called bone grafting cavities, the through holes can be round, oval, rectangular and the like, and the first through holes 7 are communicated with the pores of the honeycomb structure or the reticular structure.

In the state of the first structure 100, the arthrodesis device further includes a second through hole 8, called a bone graft hole, provided in the posterior wall 2, and the second through hole 8 is a through hole that is formed in the anterior-posterior direction as an axial direction and that penetrates the first through hole 7, and may be circular, elliptical, rectangular, or the like.

Through set up the bone grafting hole and set up the bone grafting chamber that link up at the integration ware central authorities behind the integration ware 2, can implant autologous bone or xenogenous bone to better realization osseous tissue fuses.

The honeycomb structure inside the fusion cage has a plurality of pores, so that the elastic modulus of the fusion cage can be reduced, the fusion cage is closer to the elastic modulus of human bones, stress shielding is reduced, meanwhile, the honeycomb structure is communicated with the bone grafting cavity and the bone grafting holes, and bone tissues can grow into the fusion cage through the pores, so that a better fusion effect is achieved.

The austenite phase shape structure (the first structure 100) of the fusion cage is a hollow polyhedron with a high front and a low rear, and the front wall 1 protrudes forwards and is in an arc shape and is higher than the rear wall 2. The center of the back wall 2 is provided with a bone grafting hole, the left side wall 3 is parallel to the right side wall 4, the upper surface 5 is an integrally convex arc curved surface and is matched with the shape of the lower articular surface of the atlas lateral mass, the lower surface 6 is flat, and the center of the fusion cage is provided with a bone grafting cavity (a first through hole 7) which penetrates through the upper surface 5 and the lower surface 6. The interior of the fusion cage is filled with a complex honeycomb structure or a net structure, and the pores of the honeycomb structure are communicated with the bone grafting cavity and the bone grafting holes (second through holes 8).

In a preferred embodiment of the atlantoaxial lateral mass arthrodesis cage provided by the invention, the atlantoaxial lateral mass arthrodesis cage is made of nickel titanium shape memory alloy through 3D printing, has a one-way shape memory effect, and has two shape structures of a martensite phase (a second structure) at a low temperature and an austenite phase (a first structure) at a high temperature. In the martensite phase, the cage is a flat hollow polyhedron, and similar to the austenite phase structure before compression, the cage also comprises a front wall 1, a rear wall 2, a left side wall 3, a right side wall 4, an upper surface 5 and a lower surface 6. The front wall 1 protrudes forwards to form a circular arc shape, so that the implant is convenient. The center of the back wall 2 is provided with a round-corner rectangular hole which is a bone grafting hole. The left side wall 3 and the right side wall 4 are arranged in parallel. The upper surface 5 is contacted with the lower articular surface of the atlas lateral mass, the lower surface 6 is contacted with the upper articular surface of the axis lateral mass, and the center is provided with a round-corner rectangular through hole which runs through the upper surface 5 and the lower surface 6 and is a bone grafting cavity. The interior of the fusion cage is filled with a compressed honeycomb structure, and the honeycomb structure is communicated with the bone grafting cavity and the bone grafting holes. The fusion cage is implanted in a low-temperature martensite phase state, phase change occurs along with temperature rise after implantation, and the fusion cage is changed into an austenite phase shape structure due to the complex shape of a compressed honeycomb structure in the fusion cage. The whole height of the austenite phase shape structure is higher than that of the martensite phase shape structure, and the front wall 1 is higher than the rear wall 2, so that the dentate process of the axis can be moved forwards and downwards, and the aim of resetting the atlantoaxial dislocation is achieved. The overall height is 9mm to 15mm in the austenite phase and 3mm to 5mm in the compressed martensite phase. The atlantoaxial dislocation reduction system can be customized in a personalized way, is convenient to implant, can be effectively reset, is stable in support and can be used for porous fusion, and can be applied to the operation treatment of patients with atlantoaxial dislocation.

In the existing atlantoaxial lateral mass joint fusion cage, the atlantoaxial lateral mass joint generally has the appearance of being equal in front and back or low in front and high in back, which is convenient for implantation from the back of the atlantoaxial lateral mass joint in posterior surgery, but the anteversion problem of the atlantoaxial lateral mass joint cannot be corrected by the structure; when the fusion cage with the shape of high front and low back is implanted, a larger operation space is needed, a larger implantation opening needs to be cut, and the fusion cage can be implanted only by prying the atlantoaxial lateral mass joint, so that the operation is inconvenient and complicated, the stability of the joint is damaged, and the treatment effect is seriously influenced.

Furthermore, the shape and size parameters of the atlantoaxial side block joint fusion cage provided by the invention can be preset according to different bone shape and size requirements, the atlantoaxial side block joint fusion cage is integrally formed by 3D printing, and the length, the width, the height, the curvature of the upper surface 5, the included angle between the front wall 1 and the rear wall 2 and other external shape parameters, and the internal structure parameters such as aperture, porosity and the like of the atlantoaxial side block joint fusion cage can be customized according to the atlantoaxial side block joint form of a patient, so that the optimal resetting, supporting and fusion effects are achieved.

In addition, the 3D printing technology can be used for manufacturing three-dimensional entities with complex shapes, and has the advantages of simple and convenient operation, short production period and individuation customization.

The general process of manufacturing the atlantoaxial lateral mass joint fusion cage by using the 3D printing technology is as follows: three-dimensional image data of a skull-neck junction area of a patient is obtained through CT scanning, and the three-dimensional image data comprises various indexes for evaluating atlantoaxial dislocation and skull base depression degree and various data of atlantoaxial side block joint morphology, such as joint length, width, inclination angle and the like. And then, according to the data, the atlantoaxial lateral mass joint fusion cage is designed by computer aided design software, so that the atlantoaxial lateral mass joint fusion cage can be matched with the atlantoaxial lateral mass joint form of the patient and can achieve the optimal resetting effect. And finally, carrying out integrated 3D printing by using the nickel-titanium alloy powder as a raw material through a 3D printer according to design data.

The following gives the operation procedure for implanting the atlantoaxial lateral mass fusion cage provided by the present invention:

the nasal trachea cannula is full anesthesia, in prone position, and a Sugitar four-nail head frame is used for fixing the skull and vertically drawing. The posterior cervical median approach is adopted to prop open the posterior cervical muscle, the atlantoaxial is exposed under a microscope, and atlantoaxial screws are implanted respectively. The nerve root of the left C2 is retracted, the lateral mass of the atlantoaxial joint capsule on the left side is cut open, and the cartilage of the joint surface is scraped. Flushing the surgical area with ice-saline water for cooling, implanting the fusion device stored at low temperature into the lateral mass joint of the atlantoaxial on the left side, and adjusting the implantation position under X-ray fluoroscopy. After the position is satisfied, the operation area is washed by warm saline water to raise the temperature, and when the temperature reaches the phase transition temperature of the nickel-titanium shape memory alloy, the fusion device is changed into an austenite phase shape structure. And implanting the autologous cancellous bone particles of the ilium through the bone grafting hole, compacting, and implanting the autologous cancellous bone particles of the ilium in the joint gap around the fusion device. In the same way, the right fusion cage was implanted into the right atlantoaxial lateral mass joint and bone was implanted.

The atlantoaxial lateral mass joint fusion cage provided by the invention has the advantages of individuation customization, convenient implantation, effective reduction, stable support, porous fusion and the like, and can be applied to the operation treatment of the atlantoaxial dislocation patient.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.