CN107252372B - Mortise and tenon type cervical vertebra intervertebral fixer - Google Patents

Abstract

The invention relates to the field of medical devices, in particular to a mortise and tenon type cervical intervertebral fixator, comprising an intervertebral fixator body for inserting into the intervertebral space of the cervical spine, and a vertical wing-shaped rotatably connected to one end of the intervertebral fixator body. The component, the vertical wing-shaped part includes a bearing and a tenon, the bearing is used to limit the rotation connection with the body of the intervertebral fixator, and the bearing extends along the length direction of the cervical spine to both sides of the body of the intervertebral fixator. Compared with the cervical intervertebral fixation device in the prior art, this device is suitable for intervertebral fusion and fixation of diseased segments in anterior cervical decompression surgery. The fixation will squeeze the upper and lower vertebral bodies to the body of the intervertebral fixator, so that the upper and lower vertebral bodies and the intervertebral fixator form a firm and stable whole, with better stability and reliability, limiting the depth of the fixator and preventing its return. retreat and provide favorable conditions for the final integration.

Description

Mortise and Tenon Cervical Intervertebral Fixator

technical field

The invention relates to the field of medical devices, in particular to a mortise and tenon type cervical intervertebral fixator.

Background technique

The main pathological basis of cervical spondylosis is the degeneration and protrusion of the intervertebral disc, the formation of osteophytes at the posterior border of adjacent vertebral bodies, and the thickening or ossification of the posterior longitudinal ligament, resulting in compression of the spinal cord, nerve roots and blood vessels. Surgery for cervical spondylosis mainly focuses on the intervertebral space. The classic surgical operation is to remove the degenerated and protruding intervertebral disc, clean up the osteophyte at the posterior edge of the vertebral body, remove the thickened or ossified posterior longitudinal ligament and its adhesions, sometimes decompress the nerve root at the same time, and then implant bone in the intervertebral body fusion. This cervical decompression and fusion operation takes the patient's vertebral body or intervertebral disc as the center, and performs intervertebral bone grafting or implantation of intervertebral implants from the upper to lower normal vertebral bodies in the lesion area to generate bone in multiple segments. Sexual connection, fusion into one, forming a mechanical whole, to achieve the purpose of treating spinal injuries, eliminating pain, preventing deformity, rebuilding spinal stability and protecting spinal cord nerves.

Mortise and tenon is a concave-convex connection method used on two components. The protruding part is called tenon (or tenon); the concave part is called tenon (or tenon, tenon and groove), and the tenon and tenon bite together to play a connecting role. This is the main structure of ancient Chinese buildings, furniture and other wooden instruments. The mortise and tenon structure is a combination of tenon and tenon. It is an ingenious combination of more and less, high and low, long and short parts, which can effectively limit the twisting of components in all directions. The most basic mortise and tenon structure is composed of two components, the mortise of one is inserted into the mortise of the other, so that the two components are connected and fixed.

Mortise and tenon structure is the main structural method used in ancient Chinese architectural construction and traditional furniture production. By combining and supporting each other, each component turns the thin individual into a seamless whole. It overcomes the shortcomings of individual thinness, and the combined whole can withstand huge stress. In addition, this special flexible structure allows a certain amount of deformation while bearing a large load. This is also the reason why many ancient Chinese buildings can stand for a hundred years without being fixed with an iron nail. Mortise and tenon is the epitome of the broad and profound Chinese traditional culture, the essence of ancient craftsmanship, and an extremely delicate invention.

Autologous iliac bone grafting was once considered the "gold standard" for intervertebral fusion. However, the use of bone grafts alone lacks effective initial stability, and the bone grafts have risks such as loosening, prolapse, and compression of the trachea, esophagus, or spinal cord. The bone graft may move abnormally after weight-bearing in the later stage, and a certain rate of nonunion and pseudarthrosis may occur. At the same time, the bone graft also lacks firmness, which is prone to decalcification and absorption of the bone of the bone graft, which reduces the height of the front vertebral body, and the rear facet joints bear abnormal stress, causing osteoarthritis and bone hyperplasia. In order to solve the above problems, researchers have designed a wide variety of intervertebral implants to restore the height of the intervertebral space, maintain the physiological curvature of the cervical spine, and meet the requirements of firm fixation. At present, the cervical intervertebral fixation devices on the market are generally hollow columnar or cubic structures. They are fixed by the tooth-like protrusions on the upper and lower surfaces and screws screwed into the upper and lower vertebral bodies. Generally, they need to be used in conjunction with an anterior cervical fixation plate or locking plate. , to increase stability, this fixation method is one of the current mainstream surgical methods, the structure of the cervical intervertebral fixation device is more complicated, the method of using this cervical intervertebral fixation device is more difficult to operate, and the stability and reliability are relatively high. Difference.

Contents of the invention

In view of the technical problems existing in the prior art, the object of the present invention is to provide a mortise and tenon type cervical intervertebral fixator, which is suitable for intervertebral fusion and fixation of diseased segments in anterior cervical decompression surgery, and can fix intervertebral The fixator is tightly embedded in the intervertebral space, and the upper and lower vertebral bodies are combined into a solid whole to achieve the purpose of limiting the depth of the fixator and preventing its regression. The stability and reliability are good.

In order to achieve the above object, the present invention adopts following technical scheme:

The mortise and tenon type cervical intervertebral fixator includes an intervertebral fixator body for insertion into the intervertebral space of the cervical spine, and a vertical wing-shaped part that is rotatably connected to one end of the intervertebral fixator body. The vertical wing-shaped part includes a bearing and a tenon. The bearing is used to limit the rotational connection with the body of the intervertebral fixator, and the bearing extends along the length direction of the cervical spine to both sides of the body of the intervertebral fixator. After adopting this structure, during the operation, the osteotome chisels the upper and lower vertebral body anterior bone grooves in the intervertebral space of the operating segment to make a mortise. The mortise and tenon are mortised together to achieve the purpose of tightly fixing the intervertebral fixator and the cervical spine and limiting the depth of the intervertebral fixator body implanted into the intervertebral space.

One end of the body of the intervertebral fixator is provided with a groove, the bearing is located in the groove, and the bearing abuts against the bottom surface of the groove. For the convex cylindrical surface, the bearing is provided with limiting shoulders, which are respectively located on both sides of the outwardly protruding cylindrical surface, corresponding to the limiting shoulders, and the bottom surface of the groove is provided with a limiting slope. After adopting this structure, the horizontal placement of the body of the intervertebral fixator can be ensured by controlling the vertical direction of the vertical wing-shaped components. The vertical wing-shaped part and the body of the intervertebral fixator have a certain degree of mobility, and the angle can be adjusted as required to adapt to the angle formed by the intervertebral space and the longitudinal axis of the cervical spine in different individuals and diseased segments.

It also includes a cylindrical pin, the vertical wing part is combined with the body of the intervertebral fixator through the cylindrical pin, and the bearing rotates around the cylindrical pin. After adopting this structure, it is convenient to assemble the intervertebral fixator during operation.

The two sides of the body of the intervertebral fixer are provided with a plurality of locking teeth, and the direction of the locking teeth faces the length direction of the human spine, and the locking teeth located on both sides of the body of the intervertebral fixer are arranged symmetrically. Provide good support and grip for the body of the intervertebral fixator.

The locking tooth is a right-angled triangular prism structure, and the slope of the locking tooth faces the insertion direction of the body of the intervertebral fixator. The above is the most preferred embodiment of the bayonet structure.

The locking teeth include large locking teeth and small locking teeth, and the large locking teeth are arranged on both sides of the small locking teeth, close to the two ends of the body of the intervertebral fixator. The above is the most preferred embodiment of the bayonet arrangement.

The body of the intervertebral fixer is provided with a hollow. It can not only be used to place bone grains to facilitate interosseous fusion, but also reduce the overall weight of the intervertebral fixator.

The hollow of the body of the intervertebral fixator includes a crescent-shaped hollow arranged in the middle of the body of the intervertebral fixator and trapezoidal hollows arranged on both sides of the body of the intervertebral fixator. The above structure is a preferred embodiment.

Both sides of the body of the intervertebral fixer are provided with horizontal grooves, and the connecting line of the two horizontal grooves is perpendicular to the length direction of the human spine. Used to fix the gripper during surgery.

The body of the intervertebral fixator gradually narrows along the direction of insertion into the intervertebral space. Easy insertion into intervertebral space.

Generally speaking, the present invention has following advantages:

Compared with the cervical intervertebral fixation device in the prior art, this device is suitable for intervertebral fusion and fixation of diseased segments in anterior cervical decompression surgery. The fixation will squeeze the upper and lower vertebral bodies to the body of the intervertebral fixator, so that the upper and lower vertebral bodies and the intervertebral fixator form a firm and stable whole, with better stability and reliability, limiting the depth of the fixator and preventing its return. retreat and provide favorable conditions for the final integration.

Description of drawings

Fig. 1 is a three-dimensional structural schematic view of a specific embodiment of the mortise and tenon type cervical intervertebral fixator of the present invention.

Fig. 2 is a front view of a specific embodiment of the mortise and tenon type cervical intervertebral fixator of the present invention.

Fig. 3 is a left side view of Fig. 2 .

FIG. 4 is a top view of FIG. 2 .

In Figures 1 to 4, 1 is the body of the intervertebral fixator; 2 is the vertical wing part; 3 is the cylindrical pin.

Fig. 5 is a schematic diagram of the three-dimensional structure of the intervertebral fixator body of the mortise and tenon type cervical intervertebral fixator of the present invention.

In Figure 5, 1-1 is a groove; 1-2 is a crescent-shaped hollow; 1-3 is an inwardly concave cylindrical surface; 1-4 is a trapezoidal hollow; 1-5 is a horizontal groove; Small locking teeth; 1-7 are large locking teeth; 1-8 are cylindrical jacks; 1-9 are limit slopes.

Fig. 6 is a schematic diagram of the three-dimensional structure of the vertical wing-shaped part of the mortise and tenon type cervical intervertebral fixator of the present invention.

Fig. 7 is a sagittal schematic view of the embodiment shown in Fig. 6 .

In Figures 6 to 7, 2-1 is a bearing; 2-2 is a tenon; 2-3 is a cylindrical surface protruding outward; 2-4 is a cutting edge; Limit card shoulder.

Detailed ways

The present invention will be described in further detail below.

As shown in Figures 1 to 4, the mortise-and-tenon cervical intervertebral fixator includes an intervertebral fixator body 1 for insertion into the intervertebral space of the cervical spine, and a vertical wing-shaped rotatably connected to one end of the intervertebral fixator body. Part 2, as shown in Figures 5 to 7, the vertical wing-shaped part 2 includes a bearing 2-1 and a tenon 2-2, the bearing 2-1 is used to limit the rotational connection with the intervertebral fixator body 1, and the bearing 2-1 Along the length direction of the cervical spine, tenon heads 2-2 are respectively extended to both sides of the body part 1 of the intervertebral fixator. After adopting this structure, during the operation, the bone knife chisels out the bone groove at the front edge of the upper and lower vertebral bodies in the intervertebral space of the operating segment to make a mortise. -2 is inserted into the mortise, and the mortise 2-2 and the mortise are engaged with each other, so as to achieve the purpose of tightly fixing the intervertebral fixator and the cervical spine and limiting the depth of implantation of the intervertebral fixator body 1 into the intervertebral space. The side of the vertical wing part 2 facing the opposite direction of the intervertebral fixator body 1 is a smooth arc surface, and the tenon 2-2 is provided with a sharp cutting edge 2-4 facing the direction of the intervertebral fixator body 1 . The sharp cutting edge 2-4 is convenient for the tenon 2-2 to be inserted into the intervertebral space when the intervertebral fixator is implanted into the intervertebral space.

As shown in Figures 1 to 7, one end of the intervertebral fixator body 1 is provided with a groove 1-1, the bearing 2-1 is located in the groove 1-1, and the bearing 2-1 abuts against the groove 1-1 The bottom surface of the groove 1-1 is provided with an inwardly recessed cylindrical surface 1-3, in cooperation with it, the bearing 2-1 is provided with an outwardly protruding cylindrical surface 2-3, and the bearing 2-1 is provided with a limit The card shoulders 2-6 are respectively located on both sides of the outwardly protruding cylindrical surface 2-3, corresponding to the limit card shoulders 2-6, and the bottom surface of the groove 1-1 is provided with a limit slope 1-9. After adopting this structure, the horizontal placement of the intervertebral fixator body 1 can be ensured by controlling the vertical direction of the vertical wing-shaped component 2 . The vertical wing-shaped part 2 and the body of the intervertebral fixator 1 have a certain degree of mobility, and the angle can be adjusted according to needs to adapt to the angle formed by the intervertebral space and the longitudinal axis of the cervical spine in different individuals and diseased segments. Simultaneously, the cooperation of the limit card shoulder 2-6 and the limit bevel 1-9 makes the bearing 2-1 rotate within a limited range, ensuring that the vertical wing member 2 does not rotate excessively, within the range of motion of the normal human cervical joint. It also includes a cylindrical pin 2-5, the vertical wing part 2 is combined with the intervertebral fixator body 1 through the cylindrical pin 2-5, and the bearing 2-1 rotates around the cylindrical pin 2-5. After adopting this structure, it is only necessary to insert the cylindrical pin 2-5 into the cylindrical insertion hole 1-8 provided on the intervertebral fixator body 1, which is convenient for assembling the intervertebral fixator during operation.

As shown in Figures 1 to 5, the two sides of the intervertebral fixator body 1 are provided with several locking teeth, the direction of the locking teeth faces the length direction of the human spine, and the locking teeth on both sides of the intervertebral fixator body 1 The teeth are arranged symmetrically. The locking teeth are one-way locking teeth, and the one-way locking teeth on both sides of the body of the intervertebral fixer 1 fit closely with the top and bottom of the upper and lower vertebral bodies, and have good holding force, so as to fix the intervertebral fixator and limit its The purpose of the fallback. The locking teeth are in a right-angled triangular prism structure, and the slopes of the locking teeth face the insertion direction of the intervertebral fixator body 1 . The above is the most preferred embodiment of the bayonet structure. The locking teeth include large locking teeth 1-7 and small locking teeth 1-6, and the large locking teeth 1-7 are arranged on both sides of the small locking teeth 1-6, close to the two ends of the body 1 of the intervertebral fixator. The above is the most preferred embodiment of the bayonet arrangement.

As shown in FIGS. 1 to 5 , the body 1 of the intervertebral fixator is hollowed out. It can not only be used to place bone grains to facilitate interosseous fusion, but also reduce the overall weight of the intervertebral fixator. The hollows of the intervertebral fixator body 1 include crescent-shaped hollows 1-2 arranged in the middle of the intervertebral fixator body 1 and trapezoidal hollows 1-4 arranged on both sides of the intervertebral fixator body. The above structure is a preferred embodiment. Both sides of the intervertebral fixator body 1 are provided with horizontal grooves 1-5, and the connecting line between the two horizontal grooves 1-5 is perpendicular to the length direction of the human spine. . Used to fix the gripper during surgery. The intervertebral fixator body 1 gradually narrows along the direction of insertion into the intervertebral space. Easy insertion into intervertebral space.

As shown in Figures 1 to 7, in general, the present invention has the following advantages:

Compared with the cervical intervertebral fixation device in the prior art, it is suitable for intervertebral fusion and fixation of diseased segments in anterior cervical decompression surgery. The fixation will squeeze the upper and lower vertebral bodies to the intervertebral fixator body 1, so that the upper and lower vertebral bodies and the intervertebral fixator form a firm and stable whole, with good stability and reliability, limiting the depth of the fixator and preventing other Fall back and provide favorable conditions for eventual fusion.

As shown in Fig. 1 to Fig. 7, the usage method of this fixator is specifically described below:

After the decompression of the anterior cervical spine surgery is completed, select the vertical wing-shaped part 2 with a suitable height. If multi-segment fixation is required, the height of the tenons 2-2 is less than half of the height of the vertebral body. Taking the height of the mortise 2-2 as a reference, use a bone knife to cut bone grooves of corresponding height, width, and depth on the front edge of the upper and lower vertebral bodies in the intervertebral space of the operating segment to prepare the mortise. Note that the direction of the bone groove is perpendicular to the intervertebral space.

The height and width of the intervertebral space were detected according to the surgical trial model, and the most suitable specification of the cervical intervertebral fixator body 1 was determined in combination with the experience of the surgeon. After the cervical intervertebral fixator body 1 is selected, the prepared mortise-cut bone slices or autologous iliac crest and allogeneic bone grains are implanted into the hollow space of the intervertebral fixator body 1 and compacted to form bone grafts. It is advisable that the block fills up the intervertebral fixator body 1 and is flush with the top, bottom and left and right sides.

Fit the bearing 2-1 in the middle of the vertical wing-shaped part 2 into the groove 1-1 at the front end of the intervertebral fixator body 1, and insert the cylindrical pin 2-5 into the bearing 2-1 of the vertical wing-shaped part 2 after the fitting is accurate. 1 and the cylindrical insertion hole 1-8 at the front end of the intervertebral fixator body 1. The stability and rotational activity between the fixed vertical wing part 2 and the intervertebral fixator body 1 are tested. So far, the mortise and tenon type cervical intervertebral fixator is ready for assembly.

Put the fork-like structure at the distal end of the gripper (common to the products used in existing intervertebral fusion devices) into the horizontal grooves 1-5 on both sides of the body of the mortise and tenon cervical intervertebral fixator, and tighten the gripper The proximal bolt ensures that the gripper is well fixed to the body 1 of the intervertebral fixator.

Align the narrower end of the intervertebral fixator body 1 with the intervertebral space, align the mortise 2-2 on both sides of the vertical wing 2 along the length direction of the cervical spine with the bone groove, and hit the proximal end of the gripper to control the hitting force and rhythm, closely observe the implantation direction and depth of body part 1 of the intervertebral fixator. Keep the front edge of the intervertebral fixator body 1 and the bottom surface of the vertical wing part 2 flush with the front edges of the upper and lower vertebral bodies, and the mortise and tenon cervical intervertebral fixator is implanted in place.

Moderately pull the gripper handle, check the fixing depth and firmness of the mortise and tenon cervical intervertebral fixator, and loosen the proximal bolt of the gripper. The mortise and tenon cervical intervertebral fixator was placed.

The mortise and tenon cervical intervertebral fixator can be used alone in anterior cervical decompression surgery, or as an auxiliary anterior cervical locking plate fixation, or combined with posterior cervical decompression and pedicle screw internal fixation. At the same time, the height of the vertical wing-shaped part 2 does not exceed half of the height of the vertebral body, so it can also be used to perform operations on two or more consecutive segments of intervertebral lesions. The specific situation needs to be considered comprehensively in combination with the patient's condition and the experience of the surgeon.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (8)

1. The mortise and tenon type cervical intervertebral fixator is characterized in that: it includes an intervertebral fixator body for inserting into the intervertebral space of the cervical vertebrae, and a vertical wing-shaped part that is rotatably connected to one end of the intervertebral fixator body. The components include a bearing and a tenon. The bearing is used to limit the rotation connection with the body of the intervertebral fixator. The bearing extends along the length direction of the cervical spine to both sides of the body of the intervertebral fixator. The tenons of the body of the intervertebral fixator One end is provided with a groove, the bearing is located in the groove, the bearing abuts against the bottom surface of the groove, the bottom surface of the groove is provided with an inwardly concave cylindrical surface, and matched with it, the bearing is provided with an outwardly convex cylindrical surface, the bearing Limiting shoulders are provided, which are respectively located on both sides of the outwardly protruding cylindrical surface, corresponding to the limiting shoulders, and the bottom surface of the groove is provided with a limiting slope; it also includes a cylindrical pin, and the end of the body of the intervertebral fixator. The two side walls of the groove are provided with cylindrical sockets, the vertical wing parts are combined with the body of the intervertebral fixator through the cylindrical pins, and the bearings rotate around the cylindrical pins. 2. According to the mortise and tenon type cervical intervertebral fixer according to claim 1, it is characterized in that: both sides of the intervertebral fixator body are provided with several locking teeth, and the direction of the locking teeth faces the length direction of the human spine, located at The locking teeth on both sides of the body of the intervertebral fixer are arranged symmetrically. 3. The mortise and tenon type cervical intervertebral fixator according to claim 2, wherein the locking teeth are in a right-angled triangular prism structure, and the slopes of the locking teeth face the insertion direction of the body of the intervertebral fixator. 4. The mortise and tenon type cervical intervertebral fixator according to claim 3, wherein the locking teeth include large locking teeth and small locking teeth, and the large locking teeth are arranged on both sides of the small locking teeth, close to the intervertebral fixator both ends of the body. 5. The mortise and tenon type cervical intervertebral fixator according to claim 1, wherein the body of the intervertebral fixator is hollowed out. 6. The mortise and tenon cervical intervertebral fixator according to claim 5, characterized in that: the hollow of the intervertebral fixator body includes a crescent-shaped hollow arranged in the middle of the intervertebral fixator body and a crescent-shaped hollow arranged in the vertebral body. The trapezoidal hollows on both sides of the body of the intermediate fixer. 7. The mortise and tenon type cervical intervertebral fixator according to claim 1, characterized in that: the body of the intervertebral fixator is provided with horizontal grooves on both sides, and the connecting line of the two horizontal grooves is perpendicular to the length of the human spine direction. 8. The mortise and tenon cervical intervertebral fixator according to claim 1, characterized in that: the body of the intervertebral fixator gradually narrows along the direction of insertion into the intervertebral space.

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