CN209899671U - Anterior cervical self-fixation artificial vertebral body - Google Patents

Abstract

The utility model discloses an anterior cervical self-fixing artificial vertebral body, which belongs to the technical field of medical prosthesis manufacturing. It is composed of integrated vertebral body parts, and the main features include the upper end arc surface, the lower end slope, the end surface sawtooth structure, the end surface microporous structure, the side wall diamond hole, the rear wall microporous structure, the front wall arc structure, the rear wall arc structure and The self-fixing screw hole structure of the front wall. The utility model eliminates the use of the traditional anterior cervical approach titanium plate on the premise of preserving the stability of the spinal segment after surgery, the breakthrough effectively reduces the complexity of the anterior cervical approach cervical vertebral body subtotal resection and fusion, and shortens the operation. Time, reduce the amount of bleeding in the book, optimize the biomechanical conduction mode of the anterior cervical implantation device, and avoid many complications caused by the anterior cervical plate. Through the above designed utility model, the anterior cervical self-fixation artificial vertebral body can effectively reduce many complications of the traditional titanium cage, and improve the prognosis of patients after subtotal cervical vertebral body resection and fusion.

Description

Anterior cervical self-fixation artificial vertebral body

【Technical field】

The utility model belongs to the technical field of medical prosthesis manufacturing, and relates to the implantation of a prosthesis after a cervical vertebral body and its adjacent intervertebral disc lesions are removed.

【Background technique】

With the improvement of modern people's living standards and the change of lifestyle, the incidence of cervical vertebral disease is gradually increasing. Neck pain has become one of the main reasons for clinic visits, with cervical spine problems accounting for 1.5% of all diseases. Anterior cervical subtotal resection and fusion is one of the most commonly used surgical methods for the treatment of cervical spine diseases, and is widely used in cervical spine degenerative diseases, trauma, tumors and other diseases.

At present, the most commonly used instrument in anterior cervical subtotal resection and fusion is a titanium cage combined with an anterior cervical plate. This method has been proven to provide sufficient stability for postoperative reconstruction of the cervical spine, thereby promoting fusion, preventing Displacement or collapse of titanium cages is widely used by spine surgeons. However, there are still many shortcomings in this method: the installation of the anterior steel plate complicates the operation, prolongs the operation time, and increases the amount of blood loss; the compression of the anterior steel plate on the adjacent tissues can cause damage to the esophagus and trachea, dysphagia, and acceleration Degenerative lesions of adjacent segments; the traditional titanium cage is a simple cylindrical structure, and the two ends of the cage need to be trimmed based on the surgeon's experience during the operation. The bulge eventually leads to the destruction of the endplate structure and the sinking of the titanium cage, which destroys the stability of the cervical spine after surgery. The above complications will seriously affect the postoperative rehabilitation and life safety of patients, and urgently need to be solved.

At present, there is no effective and simple method or technology to solve the above-mentioned problems caused by the anterior neck plate.

【Content of utility model】

The purpose of the utility model is to solve the shortcomings of the above-mentioned traditional titanium cage titanium plate, and to provide an anterior cervical self-fixation artificial vertebral body with simple structure and adaptable anatomical shape.

In order to achieve the above object, the utility model adopts the following technical solutions to be realized:

An anterior cervical self-fixation artificial vertebral body, comprising a hollow vertebral body part, the upper end, front wall, rear wall, front side angle and rear side wall of the vertebral body part are all arc structures, and the lower end has no inclined surface structure; The upper end surface and the lower end surface of the component are serrated, and the two side walls of the upper end surface and the lower end surface and the top end of the rear wall are provided with micro-hole structures; screw holes.

The further improvement of the present utility model is:

The vertebral body part is an integrated structure made of titanium alloy 3D printing, and is fixed and installed by screws; 12mm.

The vertebral body part is a square with four corners in cross section and an arc angle at the front and back. The radius of the front wall is 15mm, the radius of the back wall is 33mm, the radius of the front side is 2mm, and the radius of the back is 3mm;

The front and rear walls of the vertebral body parts each have an arc that protrudes forward, and the arc is matched with the anterior and posterior arcs of the subtotal resection vertebral body, so that the front end of the vertebral body part after implantation will not exceed the connection line between the front and rear walls of the upper and lower vertebral bodies, It will not compress any cervical vertebrae anterior and posterior tissue structures; the junctions of the front and rear side walls and the left and right side walls of the vertebral body parts are filled with rounded corners to prevent stress concentration; the upper and lower ends of the vertebral body parts are open, and the interior is reserved for Receiving cavity for implantation of bone grafts.

The front wall of the vertebral body part is provided with four screw holes.

The four screw holes are arranged symmetrically up and down, and the screw holes on both sides of the central axis are distributed with the central axis as the symmetry line. The diameters of the four screw holes are all 3.5-4mm; the four screw holes are all set as countersunk holes with threads, and the screws and the vertebral body parts are self-locking; the diameter of the nut part of the four screw holes is 5mm and the height is 1mm; A wrapping structure with a thickness of 1mm is provided around the hole.

The back wall of the vertebral body part is embedded with a layer of honeycomb-like microporous structure. The honeycomb-like microporous structure is formed by an array of rhombic hexahedral unit cells, with a size of 1 × 8 × 13.5 mm, a pore size of 400 μm, and a porosity of about 65%; all the pores in the honeycomb microporous structure are connected with each other, which can make blood vessels and soft tissues grow in.

The upper end of the vertebral body part is an arc surface structure, the arc surface structure is arranged on an inclined plane with an included angle of 9 degrees with the cross section, and the arc radius of the arc surface in the sagittal plane is 10-18 degrees.

The lower end of the vertebral body part is an inclined surface structure, which forms an angle of 10-15 degrees with the cross section.

The sawtooth includes an upper-end sawtooth structure and a lower-end sawtooth structure, and the depth of the sawtooth is 0.7-1.0 mm.

The microporous structure includes the upper end microporous structure and the lower end microporous structure.

The diamond-shaped window hole is composed of several diamond-shaped holes, and the area of the diamond-shaped holes accounts for more than 50% of the total area of the side wall of the vertebral body part.

Compared with the prior art, the utility model has the following beneficial effects:

The anterior cervical self-fixing artificial vertebral body of the utility model is combined with the anatomical features of the cervical vertebra. The serrated structure increases the friction between the vertebral body and the endplate, effectively preventing the vertebral body from shifting. The microporous structure of the upper and lower end surfaces increases the contact area with the end plate to prevent subsidence, and provides space for bone ingrowth to promote early stability. A large diamond-shaped hole is opened in the side wall, which is conducive to promoting bone fusion. Screw holes in the anterior wall allow the vertebral body to self-fix with screws.

Further, the screw holes provided on the anterior wall of the vertebral body of the present invention allow the operator to directly fix the artificial vertebral body to the upper and lower endplates with screws, without the need to additionally use an anterior cervical plate, thereby avoiding the need for an anterior cervical plate. It can lead to many complications and can provide sufficient postoperative stability to the reconstructed segment. At the same time, this fixation method changes the force support method of the traditional titanium cage titanium plate and focuses on the force conduction method, which can effectively reduce the stress of the screw-vertebral body interface, reduce the probability of screw loosening, appropriately increase the stress of the transplanted bone, and promote bone formation. , to promote integration.

Further, the diamond-shaped holes in the side wall of the vertebral body of the present invention account for a large proportion of the side wall, and these large-area diamond-shaped holes are conducive to the full contact between the bone graft in the vertebral body and the remaining bony parts of the subtotal vertebral body, and ensure that the vertebral body is fully in contact with each other. The peripheral blood supply enters the artificial vertebral body. Adequate blood supply and good bony contact are important prerequisites for bone growth and fusion. This design can effectively improve the postoperative fusion rate and fusion speed.

Further, the vertebral body of the present invention is designed by collecting the anatomical structure data of the upper and lower end plates of the vertebral body of the normal cervical vertebra, and the upper and lower ends of the artificial vertebral body are designed so that the upper and lower ends of the artificial vertebral body and the adjacent vertebral bodies end. The plates are closely fitted, thereby increasing the contact area, preventing the occurrence of stress concentration that is widespread in traditional titanium cages, and effectively reducing the probability of vertebral body collapse and subsidence.

Further, the sawtooth structure at the upper and lower ends of the vertebral body of the present invention increases the frictional force between the upper and lower end surfaces of the artificial vertebral body and the end plate, greatly reducing the possibility of the artificial vertebral body being displaced and protruding forward or backward, thereby reducing Possibility of damage to structures anterior to the cervical spine such as the esophagus, trachea, and posterior structures such as the spinal cord.

Further, the micro-hole structure of the upper and lower ends of the vertebral body of the present invention is designed according to the mechanical analysis structure, and the micro-hole structure can greatly increase the contact area between the end surface of the vertebral body and the end plate under the premise of ensuring the strength of the vertebral body, reducing the amount of damage to the vertebral body. The actual elastic modulus of the artificial vertebral body provides space for the ingrowth of bone tissue, reduces stress shielding, promotes fusion of the bone-artificial vertebral body, and increases the structural stability of the cervical spine after surgery.

Further, the micro-hole structure on the posterior wall of the vertebral body of the present invention provides an attachment point for the attachment of the posterior soft tissue, which increases the stability of the artificial vertebral body in the early postoperative period.

【Description of drawings】

Figure 1 is a front isometric view;

Figure 2 is a rear isometric view;

Figure 3 is a front view;

Figure 4 is a rear view;

Figure 5 is a top view;

Figure 6 is a schematic diagram of the installation of the self-fixating cervical artificial vertebral body book.

Among them: 1-vertebral body part; 4-front wall camber structure; 5-back wall camber structure; 6-front side angle camber structure; 7-back side wall camber structure; 8a-upper serrated structure; 8b- 9a - microporous structure at the upper end; 9b - microporous structure at the lower end; 10 - microporous structure on the rear wall; 11 - diamond-shaped window hole; 12 - screw hole.

【Detailed ways】

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. . It is to be understood that the data so used may be interchanged under appropriate circumstances so that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having" and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those expressly listed Rather, those steps or units may include other steps or units not expressly listed or inherent to these processes, methods, products or devices.

Below in conjunction with accompanying drawing, the utility model is described in further detail:

1 , 2 and 3, the anterior cervical self-fixation artificial vertebral body of the present invention is composed of a vertebral body part 1 and a screw of an integrated structure printed from titanium alloy 3D, and the vertebral body part 1 includes an upper end arc Surface structure, lower slope structure, front wall camber structure 4, rear wall camber structure 5, front side corner camber structure 6, rear side wall camber structure 7, upper end sawtooth structure 8a, lower end sawtooth structure 8b, upper end micro-holes The structure 9a, the lower end microporous structure 9b, the rear wall microporous structure 10, the side wall diamond-shaped window holes 11 and the front wall self-fixing screw holes 12.

The thickness of the front and rear walls and the left and right side walls of the vertebral body part 1 are both 2 mm, so as to increase the contact area between the end face of the vertebral body part 1 and the end plate, and provide sufficient supporting strength. The left and right diameters of the vertebral body part 1 are 13-16 mm. On the premise of satisfying the complete decompression of the spinal canal, the amount of surgical vertebral body resection is minimized, and the bony structure is preserved as much as possible, which is beneficial to postoperative fusion. The anteroposterior diameter of the vertebral body part 1 is 12 mm, which matches the anteroposterior diameter of the human cervical vertebral body. The front and rear walls of the vertebral body part 1 each have an arc that protrudes forward, and the arc is matched with the anterior and posterior arcs of the subtotal resection vertebral body, so that the front end of the vertebral body part 1 will not exceed the connection line between the anterior and posterior walls of the upper and lower vertebral bodies after implantation. , will not cause compression to any cervical vertebrae anterior and posterior tissue structures. The junction of the front and rear and left and right side walls of the vertebral body part 1 is rounded to prevent the stress concentration caused by the sharp intersection angle. Both the upper and lower ends of the vertebral body component 1 retain sufficient opening area, and a sufficient volume of accommodating cavity is reserved inside the vertebral body to facilitate the implantation of the grafted bone.

The front wall of the vertebral body part 1 is provided with four screw holes 12 , two at the upper end and two at the lower end. The screw holes on both sides of the central axis are distributed with the central axis as the symmetrical line, and the included angles of all the screw holes and the cross section are consistent, which are 40°±10°. This angle is designed in combination with the anatomical structure of the normal cervical vertebral body to ensure that the screw can be smoothly implanted into the vertebral body through the upper and lower endplates through the screw hole, and to ensure that the screw will not pass through the vertebral body when the universal length screw is used. Lateral cortex. The diameter of the main body of all the screw holes 12 is 3.5-4 mm. This size not only allows the use of cortical screws with a larger diameter to ensure the fixation strength, but also allows sufficient screw hole sidewalls to be reserved on the vertebral body part 1 with a relatively small size. thickness to ensure the support strength of the vertebral body part 1 . All the screw holes 12 are set as countersunk holes with threads, which allow the screws to self-lock with the vertebral body part 1 and ensure the stability of the implanted part. The diameter of the nut part of the screw hole 12 is 5mm and the height is 1mm, and these parts are all arranged under the front wall of the vertebral body part 1, so that the top end of the nut after the screw is screwed into the nut part of the screw hole, It will not protrude from the front wall of the vertebral body part 1, completely realize the structure definition of zero notch, and prevent the compression and damage to the front structure of the cervical vertebra. A wrapping structure with a thickness of 1 mm is arranged around the screw hole 12 to ensure the stability and integrity of the screw hole 12 structure.

The back wall of the vertebral body part 1 is embedded with a layer of honeycomb-like microporous structure 10, which is formed by an array of a rhombic hexahedral unit cell unit, its pore size is 400 μm, and the porosity is about 65%. The connection allows the ingrowth of blood vessels and soft tissues. After the ingrowth of soft tissues, the stability of the artificial vertebral body can be improved. Even if non-fusion or false joint occurs, the vertebral body will not completely fall off and damage the spinal cord and anterior tissue structures in the spinal canal.

The upper end of the vertebral body part 1 is an arc structure, the arc structure 2 is established on an inclined plane with an included angle of 9 degrees with the cross section, and the arc radius of the arc surface in the sagittal plane is 10-18 degrees. The end face of the traditional titanium cage is sharply convex, and the contact between the end face and the end plate is not considered, which leads to the sinking of the titanium cage. The sagittal plane arc structure designed by the utility model makes the end face of the artificial vertebral body closely fit with the end plate, which greatly increases the contact area and reduces the occurrence rate of subsidence. The lower end of the vertebral body part 1 is an inclined surface structure 3, which forms an angle of 10-15 degrees with the cross section. The inclined surface increases the contact area between the lower end surface of the vertebral body part 1 and the end plate, and reduces the occurrence rate of subsidence.

The upper and lower end faces of the vertebral body part 1 are designed with serrations, and the depth of the serrations is about 0.7-1.0 mm. The serrations can effectively increase the friction force between the upper and lower end surfaces of the vertebral body part 1 and the end plate, and prevent the vertebral body part 1 from generating cumulative small slip during the cervical movement process to induce dislocation of the vertebral body part 1 .

The two side walls of the upper and lower end surfaces of the vertebral body part 1 and the top end of the rear wall are provided with micro-hole structures. According to the finite element mechanical analysis, the microporous structure is arranged in the area where the force of the vertebral body part 1 is the least, and under the condition of ensuring the strength of the vertebral body part 1, it provides an elastic modulus adaptation area for the fusion of the bone and the vertebral body part. And the bone grows into the space, which is conducive to promoting fusion, preventing the occurrence of dislocation of false joints and vertebral body components, and increasing the stability of the cervical spine after surgery.

The side wall of the vertebral body part 1 is a diamond-shaped window hole 11 structure. The size of the diamond-shaped hole structure is not strictly limited, but on the premise of ensuring the strength of the vertebral body part 1, the area of the diamond-shaped hole should account for the total area of the side wall of the vertebral body part 1. More than 50%, in order to effectively ensure the adequate blood supply of the grafted bone and contact with the surrounding bony tissue to promote the growth and fusion of the bone.

The anterior cervical self-fixation artificial vertebral body of the utility model is used when:

After the subtotal resection of the diseased vertebral body and the treatment of the upper and lower adjacent endplates, the upper and lower vertebral bodies are opened with a distractor, and the excised autologous bone or prepared allograft bone is filled into the vertebral body from the upper and lower ends of the vertebral body part 1. Inside part 1, clamp vertebral body part 1 with hemostatic forceps and place it into the excised vertebral body part, slowly loosen the spreader, and adjust the vertebral body part 1 until it is placed in the correct position: intraoperative X-ray shows vertebral body part 1 The upper end cambered serration structure 9a is completely fitted with the upper end plate, the lower end of the vertebral body member 1 is completely fitted with the lower end plate, and the front wall of the vertebral body member 1 does not exceed the connection between the front walls of the upper and lower adjacent vertebral bodies. line. Loosen the spreader, use a medical bone drill to drill in the direction of the four screw holes 12 on the anterior wall of the vertebral body part 1, and then screw in four screws with a diameter of 3.5mm in the direction of the drilling, ensuring that the top surface of the screws is not Beyond the anterior wall of the vertebral body part 1, X-ray checks whether the position of the screw is accurate. Afterwards, the follow-up routine surgical operations of the anterior cervical subtotal corpectomy and fusion were completed.

The utility model also has the following advantages:

The utility model removes the use of the traditional anterior cervical approach titanium plate on the premise of preserving the stability of the spinal segment after operation, the breakthrough effectively reduces the complexity of the anterior cervical approach cervical vertebral body subtotal resection and fusion, and shortens the operation. Time, reduce the amount of bleeding in the book, optimize the biomechanical conduction mode of the anterior cervical implantation device, and avoid many complications caused by the anterior cervical plate. The utility model greatly optimizes the anatomical shape of the upper and lower end faces of the artificial vertebral body, making it more suitable for the anatomical shape of the adjacent end plates. This anatomical adaptation optimization increases the contact area between the artificial vertebral body and the endplate, thereby effectively reducing the stress concentration of the endplate, avoiding the structural damage of the endplate caused by excessive stress and the consequent lowering of the artificial vertebral body. Shen. The utility model combines the advantages of the microporous structure of 3D printing technology and the traditional titanium cage, the side wall of the artificial vertebral body is still opened with large holes, and the traditional titanium cage titanium mesh graft bone and subtotal resection of the remaining bony part of the vertebral body are preserved. Contact, which is conducive to speeding up the bony fusion. The use of 3D-printed microporous structure on the end face of the artificial vertebral body is beneficial to improve the local elastic modulus of the artificial vertebral body and promote the fusion of the artificial vertebral body and the bone. Through the above designed utility model, the anterior cervical self-fixation artificial vertebral body can effectively reduce many complications of the traditional titanium cage and improve the prognosis of patients after subtotal cervical vertebral body resection and fusion.

The above content is only to illustrate the technical idea of the present utility model, and cannot limit the protection scope of the present utility model. Any changes made on the basis of the technical solution according to the technical idea proposed by the present utility model fall into the scope of the present utility model. within the scope of protection of the claims.

Claims (10)

1. an anterior cervical self-fixing artificial vertebral body, is characterized in that, comprises hollow vertebral body part (1), the upper end of vertebral body part (1), front wall, rear wall, front side angle and rear side wall are all It is an arc surface structure, and the lower end has no inclined surface structure; the upper end surface and the lower end surface of the vertebral body part (1) are serrated, and the top ends of the two side walls and the rear wall of the upper end surface and the lower end surface are provided with a microporous structure; the vertebral body part (1) 1) A diamond-shaped window hole (11) is provided on the side wall, and a screw hole (12) for self-fixation is provided on the front wall. 2. The anterior cervical self-fixation artificial vertebral body according to claim 1, wherein the vertebral body part (1) is an integrated structure made of titanium alloy 3D printing, and is fixed and installed by screws; (1) The thickness of the front and rear walls and the left and right side walls are both 2 mm, the left and right diameters are both 13 to 16 mm, and the front and rear diameters are both 12 mm. 3. The anterior cervical self-fixation artificial vertebral body according to claim 1 and 2, wherein the vertebral body part (1) is a square with four corners and front and rear band arc angles in cross section, and the anterior wall radian is 15mm , the arc radius of the rear wall is 33mm, the arc radius of the front two sides is 2mm, and the arc radius of the rear two sides is 3mm; The front and rear walls of the vertebral body component (1) each have an arc that protrudes forward, and the arc is matched with the anterior and posterior arcs of the subtotal vertebral body, so that the front end of the vertebral body component (1) will not exceed the front and rear of the upper and lower vertebral bodies after implantation. The connecting line of the posterior wall will not cause any compression to the anterior and posterior tissue structures of the cervical vertebrae; the junction of the front and rear side walls and the left and right side walls of the vertebral body part (1) has a fillet to prevent stress concentration; the vertebral body part (1) ) are both open at the upper and lower ends, and a accommodating cavity for the implantation of bone grafts is reserved inside. 4. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, characterized in that, four screw holes (12) are provided on the front wall of the vertebral body part (1). 5. The anterior cervical self-fixation artificial vertebral body according to claim 4, wherein the four screw holes (12) are arranged symmetrically up and down, and the screw holes on both sides of the central axis are distributed with the central axis as a line of symmetry, and all the screw holes (12) are arranged symmetrically up and down. The included angles of the holes and the cross-sectional section are consistent, which are 40°±10°; the diameters of the main parts of the four screw holes (12) are all 3.5 to 4 mm; the four screw holes (12) are all set as countersunk holes, and The screw is self-locking with the vertebral body part (1); the diameter of the nut part of the four screw holes (12) is 5mm and the height is 1mm; a wrapping structure with a thickness of 1mm is arranged around the four screw holes (12). 6. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, wherein the rear wall of the vertebral body part (1) is embedded with a layer of honeycomb-like microporous structure (10), and the honeycomb-like microporous structure (10) is formed by an array of rhombic hexahedral unit cells, the size is 1×8×13.5mm, the pore size is 400μm, and the porosity is about 65%; They communicate with each other, allowing blood vessels and soft tissues to grow in. 7. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, wherein the upper end of the vertebral body part (1) is a curved surface structure (2), and the curved surface structure (2) is arranged on the On the inclined plane whose cross section is at an included angle of 9 degrees, the arc radius of the arc surface in the sagittal plane is 10 to 18 degrees; . 8. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, wherein the sawtooth comprises an upper sawtooth structure (8a) and a lower sawtooth structure (8b), and the depth of the sawtooth is 0.7-1.0 mm. 9. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, wherein the microporous structure comprises an upper microporous structure (9a) and a lower microporous structure (9b). 10. The anterior cervical self-fixation artificial vertebral body according to claim 1 or 2, characterized in that, the diamond-shaped window hole (11) is composed of several diamond-shaped holes, and the area of the diamond-shaped hole accounts for the total amount of the side wall of the vertebral body part (1). more than 50% of the area.

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