CN105726172A - Artificial cervical vertebra joint applicable to lower cervical vertebra - Google Patents

Abstract

The present invention provides an artificial cervical joint suitable for the lower cervical spine: it includes a vertebral body part and end plate parts arranged at both ends of the vertebral body part, and the vertebral body part includes a quadrangular prism and joints arranged at both ends of the quadrangular prism The two non-adjacent sides of the quadrangular prism are provided with tooth-like protrusion structures and a plurality of holes penetrating to the opposite side. The end plate part is an L-shaped structure, which has a structure that matches the joint socket structure at the corresponding end. The structure of the joint ball forming the ball and socket joint and the two screw holes. The present invention can produce stable support immediately after anterior cervical subtotal corpectomy and decompression surgery, and can simulate the motion function of normal cervical intervertebral joints through the upper and lower ball and socket joints, and can avoid adjacent joint joints caused by fusion surgery. Segment degeneration. At the same time, the long-term stability of the artificial cervical joint can be finally realized through bone grafting in the hole. The operation is less difficult, easy to operate, and easy to promote.

Description

A kind of artificial cervical vertebra joint suitable for lower cervical vertebra

technical field

The invention belongs to the field of medical prosthesis manufacturing, and in particular relates to an artificial cervical joint suitable for lower cervical vertebrae (cervical 3-7 vertebral bodies).

Background technique

Cervical diseases are an area of focus in spine surgery. In today's society, the number of patients with cervical spondylosis (such as cervical spondylosis, cervical spine fractures, cervical spine tumors, etc.) is increasing. For the surgical treatment of patients with various cervical spondylosis, especially cervical spondylosis and cervical fractures caused by cervical disc herniation, there are two key points of surgery: one is decompression, which needs to reduce the factors that compress the spinal cord or nerve roots to promote postoperative neuropathy. early restoration of function. The second is stability. Through various types of fusion surgery, different implant materials (such as autologous bone, allogeneic bone, and artificial vertebral body, etc.) are used to achieve long-term stability of the postoperative surgical segment. Among them, anterior cervical subtotal resection, decompression and fusion is currently the most important and most advantageous surgical procedure. It is a mature and effective surgical method for treating cervical diseases. It has been widely used in the treatment of ligament ossification, cervical trauma, cervical infection, cervical tumor and other diseases. Its advantages include that the decompression is more complete than the simple discectomy, and the fusion rate is higher. The methods of anterior intervertebral fusion include autologous bone, allograft bone and artificial vertebral bone graft fusion.

However, when cervical subtotal resection and bone graft internal fixation surgery restores the stability of the cervical spine, there are still two problems that have not been resolved: one is that the fusion of the corresponding segment will inevitably lead to the loss of the range of motion of the corresponding segment of the cervical spine; It is the degeneration acceleration of the adjacent segmental cervical intervertebral disc.

No matter what kind of fusion method is used, the problem of accelerated degeneration of adjacent segments will inevitably occur in spinal fusion, which has nothing to do with the surgical technique, but has something to do with the impact of the surgery itself on the normal biomechanical environment of the spine. After anterior cervical fusion, no matter in flexion or hyperextension, the range of motion of the upper and lower segments adjacent to the fusion increases, and the increase is more obvious in the adjacent upper segment during flexion, and the lower part is more prominent in hyperextension. The range of motion of the entire cervical spine decreased after fusion, while the percentage of motion of adjacent segments increased. As the stiffness of the fusion segment increases and the range of motion decreases, the range of motion of the entire cervical spine will be redistributed, and the range of motion of the fusion segment will be transferred to the remaining motion segments at a loss, which will lead to increased range of motion in adjacent segments and Abnormal movement patterns.

Most of the flexion and extension activities of the cervical spine occur in the cervical 4-5 and cervical 5-6 segments, where the static curvature of the cervical spine is the largest, and it is also the site of stress concentration. Once these two segments are fused, the remaining motion segments need to Compensatory bear greater exercise load, so more prone to degeneration. At present, there are many studies on the biomechanical changes of the corresponding segments after fusion, and it is believed that fusion increases the pressure on the intervertebral discs and facet joints of adjacent segments. The results of long-term follow-up showed that after anterior cervical fusion surgery, up to 92% of patients had degeneration of adjacent segments, although the clinical symptoms were not consistent with the severity of the X-ray (Goffin, Jan, Geusens, Eric , Vantomme, Nicolaas, et al. Long-term follow-up after interbody fusion of the cervical spine. JSpinal DisordTech, 2004, 17(2):79-85.). Hilibrand et al. found that about 2.9% of patients had clinical symptoms related to adjacent segment degeneration every year after anterior fusion surgery, and statistical analysis showed that 25.6% of patients would experience symptoms due to adjacent segment degeneration within 10 years. Clinical symptoms caused by changes (HilibrandAS, CarlsonGD, PalumboMA, et al.Radiculopathyandmyelopathyyatsegmentsadjacenttothesiteofapreviousanteriorcervicalarthrodesis.JBoneJointSurgAm,1999,81(4):519-528.). The results of biomechanical experiments also confirmed the increase of intervertebral disc pressure in adjacent segments after fusion surgery. The imaging evidence of the dynamic position also showed that the relative motion of the vertebral bodies of adjacent segments increased after fusion. These factors are very likely to promote the degeneration of adjacent segments after fusion.

More and more researchers have paid more and more attention to the above-mentioned impact on cervical activities after subtotal cervical corpectomy and bone grafting and internal fixation, and are trying to find a solution. In recent years, the application of spinal non-fusion technology, especially the relatively mature application of cervical artificial disc replacement technology, provides the possibility for the emergence of a spinal non-fusion technology that can not only restore the stability of the cervical spine but also preserve the physiological mobility of the cervical spine.

In view of the loss of range of motion of the surgical segment and the degeneration of adjacent segments after fusion, scientists and doctors at home and abroad have established a non-fusion spinal surgery method, whose concept is motion preservation. Artificial disc replacement (also known as discplasty) is a typical representative of non-fusion spinal surgery. Currently clinically used artificial discs mainly include Bryan prosthesis, ProDisc-C prosthesis, Prestige prosthesis, PCM prosthesis and so on. At present, it is believed that the best indication for artificial intervertebral disc replacement is single-segment cervical intervertebral disc disease and the existence of cervical physiological curvature (SekhonLH. Although the materials of various artificial intervertebral discs are different in shape, their common limitations are: 1. The intervertebral disc can only be replaced alone, and it is not suitable for combined vertebral body resection and decompression (such as vertebral body tumors, and secondary vertebral body resection) total decompression surgery). 2. Most scholars do not agree with the multi-segment intervertebral disc replacement, especially the simultaneous replacement of two adjacent intervertebral discs.

Long-segment fusion after subtotal cervical corpectomy is more likely to cause degeneration of adjacent segments. Some patients with adjacent segment degeneration after fusion need reoperation, the main way is to decompress and expand fusion. However, due to the existence of previous fusion and the increase of fused segments, the fusion rate decreased, resulting in an increased incidence of pseudarthrosis. The key is to find a non-fusion method that can not only restore segmental stability, but also restore cervical mobility in the surgical area, so as to avoid long-term adjacent segmental degeneration. In recent years, for the treatment of simple cervical intervertebral disc disease, the non-fusion technology represented by artificial cervical intervertebral disc replacement has achieved good short-term results. However, the application of spinal non-fusion technology after subtotal cervical corpectomy is still blank, which poses a challenge to spine surgeons.

To sum up, the current existing technology cannot solve the problem of retaining the range of motion of the cervical spine after cervical corpectomy and the problem of postoperative adjacent segment degeneration caused by fusion.

Contents of the invention

The object of the present invention is to provide an artificial cervical joint suitable for lower cervical vertebrae with easy installation and reliable performance.

To achieve the above object, the present invention adopts the following technical solutions:

The artificial cervical vertebral joint includes a vertebral body part and an end plate part arranged at two ends of the vertebral body part. The adjacent side is provided with a tooth-like protrusion structure and a plurality of holes penetrating to the opposite side, the end plate component includes an end plate opposite to the glenoid structure and a side plate connected to the end plate, the One side surface of the end panel is provided with a joint ball structure for cooperating with the joint socket structure of the corresponding end of the vertebral body parts to form a ball and socket joint. There is a tooth-like protrusion structure, the side panel is spliced with the correspondingly connected end panel to form an L-shaped structure, and screw holes are provided on the side panel.

The distance between the two sides of the quadrangular prism with the tooth-like protrusion structure is consistent with the width of the decompression groove after subtotal cervical vertebral body resection.

There is a difference in height between the other two sides adjacent to the two sides with the tooth-like protrusion structure on the quadrangular prism, wherein the side with a higher height is an outwardly convex arc, and the side is provided with a useful Holes for convenient instrument clamping of vertebral body components.

There are four holes arranged in two rows, and the holes are filled with cancellous bone particles.

The thickness of the side panels is gradually thinned along the direction from one side close to the corresponding end panel to the other side, and the shape of the side panels corresponds to the front surface of the cervical vertebral body, and the screw holes on the side panels The number is 2.

The screw hole is oval.

The artificial cervical vertebra joint also includes endplate component fixing screws arranged in the screw holes.

The fixing screw of the endplate part is a locking screw, and the fixing direction of the locking screw is 28.1°-28.6° outwardly inclined from the horizontal plane, and 9.5° outwardly inclined from the sagittal plane.

The artificial cervical joint is made of titanium alloy, and the surface of the artificial cervical joint in contact with the bone is provided with a hydroxyapatite coating.

The beneficial effects of the present invention are: the present invention can produce stable support immediately after anterior cervical subtotal corpectomy and decompression surgery, and can simulate the motion function of normal cervical intervertebral joints through the upper and lower ball-and-socket joints, and can avoid fusion Adjacent segmental degeneration following surgery. At the same time, the long-term stability of the artificial cervical joint can be finally achieved through bone grafting in the hole. The operation is less difficult, easy to operate, and easy to promote.

Description of drawings

Fig. 1 is the overall front view (attached screw) that is applicable to the artificial cervical vertebra joint of lower cervical vertebra;

Fig. 2 is the overall side view (without screw) that is applicable to the artificial cervical vertebra joint of lower cervical vertebra;

Fig. 3 is the overall posterior view (without screw) that is applicable to the artificial cervical vertebra joint of lower cervical vertebra;

Fig. 4 is the overall oblique view (without screw) that is applicable to the artificial cervical vertebra joint of lower cervical vertebra;

Fig. 5 is the overall side sectional view (without screw) that is applicable to the artificial cervical vertebra joint of lower cervical vertebra;

Figure 6 is a front view of the upper endplate assembly;

Figure 7 is a side view of the upper endplate component;

Figure 8 is an oblique view of the upper endplate component;

Fig. 9 is the front view of vertebral body part;

Figure 10 is a side view of a vertebral body component;

Fig. 11 is the top view of vertebral body part;

Fig. 12 is the lower view of vertebral body part;

Figure 13 is a front view of the lower endplate component;

Figure 14 is a side view of the lower endplate component;

Figure 15 is a bottom view of the lower endplate component;

In the figure: 1 is the upper endplate part, 2 is the lower endplate part, 3 is the fixing screw of the endplate part, 4 is the vertebral body part, 5 is the joint ball structure, 6 is the glenoid fossa structure, 7 is the columnar base, 8 is the In the middle line, 9 is a tooth-like protrusion structure, 10 is a screw hole, 11 is a hole groove, and 12 is a hole.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

In order to solve the problem that stability and mobility cannot be achieved after anterior cervical subtotal decompression and fusion, the present invention proposes the following suitable for lower cervical spine with both supporting and stabilizing functions and retaining the intervertebral range of motion of the cervical spine (Cervical 3-7 vertebral body) artificial cervical joint.

Figures 1-5 show the overall structure of the artificial cervical joint. The artificial cervical joint mainly includes three parts: an upper endplate part 1, a lower endplate part 2, and a vertebral body part 4, together with four endplate part fixing screws 3. The upper endplate part 1 and the lower endplate part 2 are respectively fixed on adjacent vertebral bodies by two endplate part fixing screws 3 .

The lower part of the upper endplate part 1 is an articular ball structure 5, which forms a ball-and-socket joint with the upper end glenoid structure 6 of the vertebral body part 4 and coincides with it. Similarly, the lower endplate part 2 has the same joint as the upper endplate part 1 The ball structure 5 also forms a ball-and-socket joint with the joint socket structure 6 at the lower end of the vertebral body part 4 and coincides with it.

The upper endplate part 1 is fixed on the upper vertebral body adjacent to the subtotal resection through the endplate part fixing screw 3, the articular ball structure 5 of the upper endplate part 1 and the upper end glenoid structure 6 of the vertebral body part 4 The formed ball-and-socket joint can realize three-degree-of-freedom activities (set the line along the midpoints of the front and rear edges of the vertebral body on the horizontal plane as the X-axis, the line along the midpoints of the left and right edges of the vertebral body on the horizontal plane is the Y-axis, and the vertical direction is the Z axis), and the activities of the three degrees of freedom are forward flexion and extension (that is, rotation along the Y axis), left and right lateral flexion (that is, rotation along the X axis), and left and right rotation (that is, rotation along the Z axis). The lower endplate part 2 is fixed on the adjacent lower vertebral body of the subtotal resection through the endplate part fixing screw 3, the articular ball structure 5 of the lower endplate part 2 and the lower end glenoid structure 6 of the vertebral body part 4 The formed ball-and-socket joint can realize three-degree-of-freedom activities (set the line along the midpoints of the front and rear edges of the vertebral body on the horizontal plane as the X-axis, the line along the midpoints of the left and right edges of the vertebral body on the horizontal plane is the Y-axis, and the vertical direction is the Z axis), and the activities of the three degrees of freedom are forward flexion and extension (that is, rotation along the Y axis), left and right lateral flexion (that is, rotation along the X axis), and left and right rotation (that is, rotation along the Z axis). The four hollow structures (holes) of the vertebral body part 4 are used to fill the cancellous bone during the operation, and the filled cancellous bone will be fused with the bone of the side wall of the vertebral body after subtotal resection. In addition, the small tooth-like protrusion structure 9 on the side surface of the vertebral body can increase the immediate stability of artificial vertebral body implantation and reduce the possibility of backward displacement.

The specific structure of each part is introduced below:

Referring to Figures 6-8, the upper half of the upper endplate component 1 is a plate-shaped structure with two left-right symmetrical screw holes 10, the rear surface of the plate-shaped structure is attached to the front surface of the adjacent upper vertebral body; The upper half of the plate-like structure is thinner than the lower half, so as to minimize the unnecessary notch of the upper end plate component 1 in front of the cervical spine. The two screw holes are provided with internal threads, which match the threads on the periphery of the caps of the fixing screws 3 of the end plate. The screw hole is elliptical, the long diameter of the screw hole is about 5.5mm, and the short diameter is about 4mm. The thickness of the upper endplate part 1 (the thickest part at the front and rear) is 2.7mm, and the height of the upper endplate part (that is, the height of the side panel) is 10mm, and the width of the upper endplate component is 13mm. The reason why the height of the upper endplate part 1 is almost the same as the size of the screw hole is to avoid the excessive volume of the upper endplate part 1 and form a too high notch in front of the cervical spine. The fixing screw 3 of the end plate part can be placed obliquely upward into the adjacent upper vertebral body through the screw hole. Due to the internal thread structure of the screw hole 10, it cooperates with the endplate component to fix the screw 3 to form a locking screw structure, and the screw is placed obliquely outward at an angle of 28.1° to the horizontal plane into the bone of the adjacent upper vertebral body (screw outward The angle of inclination is about 9.5°), the direction determined by this included angle can make the screw be placed as long as possible in the vertebral bone, so as to obtain the largest possible screw holding force, and fix the artificial cervical joint on the adjacent on the vertebral body for instant stabilization. The lower half (end panel) of the upper endplate part 1 is a plate-shaped structure that is attached to the adjacent upper vertebral body. Viewed from the side, the plate-like structure (end panel) of the lower half of the upper endplate part 1 and the upper half The connection of the plate-like structure (side panel) is an L-shaped structure with an angle of 85°, which is designed according to the natural angle between the front surface and the lower surface of the adjacent upper vertebral body. The plate-shaped structure (end panel) of the lower half of the upper end plate part 1 is attached to the lower surface of the adjacent upper vertebral body, and the attached surface (upper surface) is covered with denticulate protrusion structures 9 (the arrangement direction is from front to back). ), the fitting surface is shallow arc-shaped with a diameter of about 21 mm to fit the natural curvature of the endplate cortical bone below the adjacent upper vertebral body. The denticulation structure can increase the immediate stability of the upper endplate component and reduce the possibility of anterior-posterior displacement. The lower surface of the plate-shaped structure (end panel) of the lower part of the upper end plate component 1 is connected with an articular ball structure 5, the diameter of the articulation ball is 6.4mm, and the height is 3.5mm (the height of the columnar base 7 connected above the articular ball is 1mm).

9-12, the width of the vertebral body part 4 is 14 mm, and the width of the vertebral body part is consistent with the width of the decompression groove after subtotal vertebral body resection. The average height of the front surface of the vertebral body parts is about 14.7mm, and the average height of the back surface of the vertebral body parts is about 14mm. The difference between the height of the front surface of the vertebral body parts 4 and the height of the back surface is to adapt to the natural curvature formed by cervical lordosis . There are two circular hole grooves 11 whose diameters are respectively 1.8 mm in the middle of the front surface. The design of the two small round hole slots is to facilitate the insertion of instruments into the two small round hole slots, clamp the vertebral body components, and place them into the decompression slot after subtotal vertebral body resection. The side surfaces of the vertebral body parts 4 (surfaces adjacent to the front and rear surfaces) can be seen with denticles 9 (arranged from front to back). The denticles can increase the immediate stability of the vertebral body parts 4 and reduce the anterior and posterior possibility of displacement. Four circular holes 12 with different diameters can be seen on the side surface. The diameters of the four circular holes are respectively 4mm in diameter of the upper two circular holes, 3.8mm in diameter of the next circular hole in front, and 3.6mm in diameter of the next circular hole in the back. 4 circular holes respectively run through the vertebral body part 4 horizontally, and the 4 circular holes are used to fill cancellous bone particles, and the filled cancellous bone particles will fuse with the bone on both sides of the decompression groove after subtotal vertebral body resection. In order to obtain the final permanent stabilization of the vertebral body part 4 . The maximum depth of the vertebral body part 4 from the front surface to the rear surface (i.e. the midline 8) is 14mm, and the depth of the vertebral body part 4 gradually decreases from the midline 8 to both sides. The surface is shallowly curved. The upper surface and the lower surface of the vertebral body part 4 are respectively a glenoid structure 6, which coincide with the joint ball structure 5 of the upper endplate part 1 and the lower endplate part 2 respectively and form a ball-and-socket joint structure. The diameter of the glenoid structure is It is 6.4mm and the height is 3.5mm.

Referring to Figures 13-15, the lower half (side panel) of the lower endplate component 2 is a plate-like structure with two symmetrical screw holes 10, the rear surface of the plate-like structure is in contact with the front surface of the adjacent lower vertebral body Fitting; the lower half of the plate-like structure is thinner than the upper half to minimize unnecessary notching of the lower endplate components anterior to the cervical spine. The two screw holes are internally threaded and are matched with the fixing screws 3 of the end plate components. The screw hole is elliptical, the long diameter of the ellipse is about 4.2mm, the short diameter is about 3.7mm, the thickness of the lower endplate part (the thickest part before and after) is 2.7mm, the height of the lower endplate part (that is, the lower half of the lower endplate part) The height of the part) is 9 mm and the width of the lower endplate part is 13 mm. Like the upper endplate part 1, the reason why the height of the lower endplate part is only about the same size as the screw hole is to prevent the lower endplate part 2 from being too bulky and forming an excessively high notch in front of the cervical spine. The fixing screw 3 of the end plate part can be placed obliquely downward into the adjacent lower vertebral body through the screw hole. Due to the internal thread structure of the screw hole 10, it cooperates with the endplate component to fix the screw 3 to form a locking screw structure, and the screw is placed obliquely outward and downward into the bone of the adjacent lower vertebral body at an angle of 28.6° to the horizontal plane (the screw is outward The angle of inclination is about 9.5°), the direction determined by this included angle can make the screw be placed as long as possible in the vertebral bone, so as to obtain the largest possible screw holding force, and fix the artificial cervical joint on the adjacent on the vertebral body for instant stabilization. The upper part of the lower endplate part 2 is a plate-shaped structure that fits with the adjacent lower vertebral body. Viewed from the side, the plate-shaped structure (end panel) of the upper part of the lower endplate part 2 and the plate-shaped structure of the lower part (Side panels) The connection is in an L-shaped structure with an included angle of 95°, which is designed according to the natural included angle between the front surface and the upper surface of the adjacent lower vertebral body. The plate-shaped structure (end panel) of the upper half of the lower endplate part 2 is attached to the upper surface of the adjacent lower vertebral body, and the attached surface (lower surface) is covered with denticulate protrusion structures 9 (the arrangement direction is from front to back). ). The denticles increase the immediate stability of the inferior endplate components and reduce the possibility of anterior-posterior displacement. The upper surface of the plate-shaped structure (end panel) of the upper part of the lower end plate component 1 is connected with the joint ball structure 5, the diameter of the joint ball is 6.4 mm, and the height is 3.5 mm (the height of the columnar base connected under the joint ball is 1 mm). ).

The above-mentioned artificial cervical joint system is mainly made of titanium alloy, and the surface in contact with the bone is coated with biological hydroxyapatite after plasma oxidation treatment.

The surgical indications for the above-mentioned artificial cervical joints are the same as those for cervical corpectomy and bone graft internal fixation (anterior cervical corpectomy and fusion, ACCF). For example, herniation of two adjacent cervical intervertebral discs, ossification of the posterior longitudinal ligament of the cervical spine, stenosis of the cervical spinal canal between two adjacent segments, cervical infection, cervical trauma, and cervical tumors. For patients with indications and no contraindications found in the preoperative examination, this surgical treatment requires routine preoperative preparation, and general anesthesia with endotracheal intubation is usually selected. The body position is supine, the shoulders are padded with soft pillows, the head is naturally stretched back, the back pillow is padded with a soft headband to prevent pressure sores, and small sandbags are placed on both sides of the head to prevent head rotation during the operation. The incision is generally made through an anterior cervical transverse incision to expose the affected vertebra and intervertebral disc, and the needle is positioned using a C-arm X-ray fluoroscopy machine during the operation. Cervical vertebral body spreader screws are respectively screwed into the center of the upper and lower vertebral bodies of the vertebral body to be subjected to subtotal resection, and the spreader is inserted on the spreader screws, and the upper and lower ends are spread apart. Decompression: use a sharp knife to incise the fibrous annulus of the intervertebral disc above and below the operated vertebral body, remove the intervertebral disc tissue with a nucleus pulposus forceps, and bite off the anterior cortical bone and most of the cancellous bone of the vertebral body with a three-joint sharp-nose rongeur. Pause when approaching the posterior edge of the vertebral body, completely resect the upper and lower intervertebral discs of the operating vertebral body, and repair the intervertebral articular surface to the subchondral hemorrhage with curettes, rongeurs, and round-head files, so that the endplates are roughly parallel and the bone cannot be damaged endplate. Use a nerve stripper to separate the gap between the posterior edge of the vertebral body and the posterior longitudinal ligament, and use a gun-style rongeur to gradually bite off the cortical bone at the posterior edge of the vertebral body to form a rectangular decompression groove (sometimes the posterior longitudinal ligament can be bitten off as needed). ligament), the width of the decompression groove is about 14mm. Adjust the height of the vertebral body spreader to restore the height of the cervical anterior column to normal. At this time, the subtotal excised vertebral bone is trimmed into cancellous bone granules, which are filled in the four circular holes of the vertebral body parts of the artificial cervical vertebra joint. The artificial cervical joint is inserted so that the upper endplate part fits the front surface and the lower surface of the upper vertebral body, and the lower endplate part fits the front surface and the upper surface of the lower vertebral body. Reconfirm the normal fit relationship among the three parts of the artificial cervical joint, especially the fit relationship of the ball and socket joint. A total of 4 screws were placed obliquely upward and downward through the screw holes of the upper endplate part and the lower endplate part respectively. After the C-arm X-ray machine fluoroscopy confirms that the position of the prosthesis is correct, the wound is washed to prevent drainage and sutured layer by layer. Postoperative cervical immobilization for 6 weeks, prophylactic use of antibiotics, close observation, other routine treatment of anterior cervical surgery.

The results show that the artificial cervical joint can achieve the following effects: 1. Realize the immediate stability after the anterior cervical surgery and play a supporting role. 2. Realize the immediate reconstruction of motor function after anterior cervical surgery, making its activity close to that of normal cervical spine. 3. The intraoperative operation is simple, the side injury is small, and the long-term stability after operation is reliable.

Claims (9)

1. An artificial cervical vertebral joint suitable for lower cervical vertebrae is characterized in that: the artificial cervical vertebral joint comprises a vertebral body part (4) and an endplate part arranged at both ends of the vertebral body part (4), and the vertebral body part (4) ) includes a quadrangular prism and glenoid structures (6) arranged at both ends of the quadrangular prism, tooth-like protrusion structures (9) are arranged on two non-adjacent sides of the quadrangular prism and multiple holes penetrating to the opposite side a hole (12), the end plate part includes an end plate opposite to the glenoid structure (6) and a side plate connected to the end plate, and a side surface of the end plate is provided with a The joint socket structure (6) at the corresponding end of the body part (4) cooperates to form the joint ball structure (5) of the ball and socket joint. The protruding structure (9), the side panel and the correspondingly connected end panel are spliced into an L-shaped structure, and screw holes (10) are arranged on the side panel. 2. A kind of artificial cervical joint suitable for lower cervical vertebra according to claim 1, characterized in that: the distance between the two sides of the quadrangular prism with the tooth-like protrusion structure (9) is the same as that of the cervical vertebral body. After total resection, the width of the decompression groove is the same. 3. A kind of artificial cervical joint suitable for lower cervical spine according to claim 1, characterized in that: the other two sides adjacent to the two sides with tooth-like protrusion structure on the quadrangular prism exist in height The difference is that the side with a higher height is an outwardly convex arc, and the side is provided with a hole (11) for conveniently clamping the vertebral body part (4) by the instrument. 4. A kind of artificial cervical joint suitable for lower cervical spine according to claim 1, characterized in that: said holes (12) are four, and the four holes are arranged in two rows, and said holes (12) are filled with loose Bone particles. 5. A kind of artificial cervical joint suitable for lower cervical spine according to claim 1, characterized in that: the thickness of the side panel is gradually thinned along the direction from one side close to the corresponding end panel to the other side, and the The shape of the side panel corresponds to the front surface of the cervical vertebral body, and the number of screw holes on the side panel is 2. 6. An artificial cervical joint suitable for lower cervical spine according to claim 1, characterized in that: said screw hole (10) is oval. 7 . The artificial cervical vertebral joint suitable for lower cervical vertebrae according to claim 1 , characterized in that: the artificial cervical vertebral joint further comprises endplate member fixing screws ( 3 ) arranged in the screw holes ( 10 ). 8. An artificial cervical joint suitable for the lower cervical spine according to claim 7, characterized in that: the fixing screw (3) of the end plate part is a locking screw, and the fixing direction of the locking screw is inclined outward from the horizontal plane 28.1°～28.6°, and 9.5° outward tilt from the sagittal plane. 9. An artificial cervical joint suitable for the lower cervical spine according to claim 1, characterized in that: the artificial cervical joint is made of titanium alloy, and the surface of the artificial cervical joint in contact with the bone is provided with hydroxyapatite coating.