Rod fixing apparatus for vertebra connecting member

[0001] The present invention relates to a fixed structure for fixing a rod portion such as a rod member for integrally connecting vertebrae in the spine, and more specifically, a shaft of the rod member or the like. The present invention relates to a rod portion fixing structure capable of preventing a displacement in the direction and a displacement in the rotation direction around the axis.

[0002] Conventionally, a rod portion of a connecting member such as a rod member for connecting a separated vertebral body is engaged with a head of a screw having a screw portion screwed and embedded in the vertebral body in the vertebra. A configuration in which a rod engaging portion such as a groove or an elongated hole that can be fitted is provided, and the rod engaging portion is provided with a pressing fixture such as a set screw that can press and fix the rod portion engaged with the rod engaging portion. Has been adopted.

[0003] In the above configuration, the rod portion may be misaligned with respect to the head of the screw, and it is desired to prevent the misalignment.

[0004] Therefore, as shown in FIG. 5, an enlarged engaging recess 109 is formed in the groove-shaped rod engaging portion 107 formed in the head 105 of the screw 103 having the screw portion 101 screwed and embedded in the vertebral body. Then, after engaging the enlarged engaging convex portion 113 formed on the rod portion of the connecting member 111 with the expanded engaging concave portion 109, a pressing fixture 115 such as a set screw is engaged with the rod engaging portion 107. There is a matching configuration (for example, Patent Document 1).

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 11-509453 [0006] [Problems to be Solved by the Invention] In the conventional configuration as described above, from the rod engaging portion 107 of the head 105 of the screw 103. Although it is possible to prevent the connecting member 111 from being displaced in the axial direction, it is necessary to match the installation position of the screw 103 with the position of the enlarged engaging convex portion 113 formed on the connecting member 111, which lacks versatility. I hate it. Further, the manufacturing of the connecting member 111 is troublesome, and there is a problem that it cannot be applied to a conventional general rod or the like.

[Means for Solving the Problems] The present invention has been made in view of the conventional problems as described above, and the invention according to claim 1 is a vertebral bone connecting member for connecting separated vertebral bones. It is a structure for fixing the rod portion, and is provided with a pressing fixture capable of pressing and fixing the rod portion with respect to the arc-shaped rod engaging portion that can be engaged with the rod portion, and is more than the pressing fixture. On both ends of the outer rod engaging portion, micro-protruding portions having a sharp angle capable of inserting the rod portion are provided.<u style="single">The rod portion is configured to be bent by a minute amount between the two minute protrusions when the rod portion is pressed and fixed by the pressing fixture.</u>The concave surface of the rod engaging portion between the minute protrusions provided on the rod engaging portion is formed.<u style="single">To increase friction when the rods come into contact</u>It is formed on a rough surface.

[Embodiment of the Invention] With reference to FIG. 1, FIG. 1 illustrates the case of a screw to be screwed into the vertebra as an example of an implant for fixing a vertebra connecting member. The implant is not limited to a screw, but can also be applied to a hook provided with a locking portion for locking to the vertebral arch or spinous process of a vertebra.

[0010] The screw 1 according to the present embodiment includes a screw portion 3 screwed and embedded in a vertebral body in a vertebra (not shown), and a head portion 5 provided in the screw 1 is provided with a vertebral connecting member 7. An engaging hole or an engaging groove 11 having an arc-shaped rod engaging portion 9 capable of engaging the rod portion 7R is formed. More specifically, the rod engaging portion 9 is formed at the bottom of the engaging groove 11 and is formed in a semicircular arc corresponding to the diameter of the rod portion 7R of the vertebra connecting member 7 to be fixed.

[0011] Then, as an example of a pressing fixture that presses and fixes the rod portion 7R of the vertebra connecting member 7 engaged with the engaging groove 11 to the rod engaging portion 9 in the engaging groove 11. The fixing screw 13 is detachably screwed. When the rod portion 7R is firmly pressed and fixed by the fixing screw 13, a small protruding portion 15 having an acute angle capable of holding the rod portion 7R is outside the fixing screw 13 and both ends of the rod engaging portion 9. It is formed on the side. The concave surface of the rod engaging portion 9 between the minute protrusions 15 on both sides is formed as a rough surface by, for example, sandblasting so that the friction when the rod portion 7R comes into contact with the rod portion 7R increases. ..

[0012] According to the above configuration, the threaded portion 3 of the screw 1 is screwed and embedded in the vertebral body of the vertebral bone, and the rod portion 7R of the vertebral bone connecting member 7 is engaged with the engaging groove 11 provided in the head portion 5 of the screw 1. Then, when the rod portion 7R is firmly pressed and fixed to the rod engaging portion 9 at the bottom of the engaging groove 11 by the fixing screw 13, the minute protrusions 15 and the fixing screw 13 provided on both ends of the rod engaging portion 9 are provided. The three points act on the rod portion 7R, and when the minute protruding portion 15 firmly bites the rod portion 7R, a small amount of bite is formed so as to cause scratches on the surface of the rod portion 7R. , The rod portion 7R is bent by a small amount between the two minute protrusions 15, and the rod portion 7R comes into contact with the rough surface of the rod engaging portion 9.

[0013] Therefore, the rod portion 7R of the vertebral bone connecting member 7 is prevented from being displaced in the axial direction with respect to the head portion 5 of the screw 1, and the rod portion 7R rotates about the axial center. This prevents misalignment due to this. Further, the rod portion 7R may be simply in the shape of a round bar, and the desired position of the rod portion 7R can be engaged and fixed, and the conventional problems as described above can be solved.

[0014] FIG. 2 shows a second embodiment, and in the second embodiment, the same reference numerals are given to the components having the same mechanism as that of the second embodiment, and duplicate description will be omitted.

[0015] In the second embodiment, the head portion 17H of the screw 17 provided with the screw portion 3 is formed in the spherical portion, and the spherical portion is provided with the engaging groove 19 corresponding to the engaging groove 11. A bottom member 25 is provided with a rod engaging portion 23 in which the engaging head 21 is swingably engaged and the contact surface with the rod portion is formed as a rough surface at the bottom of the engaging groove 19. It is a configuration.

[0016] The bottom member 25 has a configuration in which the rod-shaped rod engaging portion 23 is provided on the upper portion of a tubular engaging protrusion 27 having a hole 27H that can be engaged with the head portion 17H of the screw 17. A micro-projection portion 29 similar to the micro-projection portion 15 is formed at both ends of the rod engaging portion 23.

[0017] With the above configuration, the engaging head 21 can be arbitrarily swung in a desired direction with respect to the screw 17, and it is possible to easily cope with the inclination of the rod portion 7R of the vertebral connecting member 7 to be supported and fixed. It is a thing.

[0018] In the above configuration, by engaging the rod portion 7R of the vertebra connecting member 7 with the engaging groove 19 and tightening the fixing screw 13, the minute protrusion 29 provided on the rod engaging portion 23 of the bottom member 25. Therefore, the rod portion 7R can be firmly gripped, and the same effect as described above can be obtained. Further, when the fixing screw 13 is firmly tightened, the portion of the hole 27H of the bottom member 25 is firmly pressed and fixed to the head 17H of the screw 17, and the vertebral connecting member 7 is placed at a predetermined position. It can be fixedly supported.

[0019] FIG. 4 shows a third embodiment. In the third embodiment, the block 33 provided with the hook 31 that can be hooked to the vertebral arch in the vertebra is provided with the engaging groove 35 corresponding to the engaging groove 11, and the fixing screw 36A can be screwed freely. The female screw portion 36B of the above is provided, and micro-projections 37 corresponding to the micro-projections 15 are provided on both ends of the bottom of the rough surface of the engagement groove 35. The vertebra connecting member 39 has a configuration in which a hook 41 that can be hooked on the spinous process in the vertebra is provided at the tip of the rod portion 43.

[0020] According to the above configuration, the rod portion 43 of the vertebra connecting member 39 in which the hook 41 is hooked on the spinous process of the vertebra is engaged with the engaging groove 35 of the block 33, and the female screw portion 36B of the block 33 is engaged. By tightening the fixing screw 36A and firmly pressing and fixing the rod portion 43 to the bottom portion of the engaging groove 35, the same effect as that of the above-described embodiment can be obtained.

[Effect of the Invention] As will be understood from the above description, according to the present invention, the rod portion of the vertebral bone connecting member is held on both ends of the rod engaging portion which can be engaged with the rod portion. By providing the micro-projection portion that can be inserted, when the rod portion is pressed and fixed to the rod portion engaging portion by the pressing fixture, the micro-projection portion firmly grips the rod portion, and the rod portion It is possible to prevent the occurrence of misalignment and fix it, and it is possible to solve the conventional problems as described above.

BRIEF DESCRIPTION OF THE DRAWINGS [FIG. 1] FIG. 1 is an explanatory diagram showing a case where the first embodiment of the present invention is applied to a screw.

FIG. 2 is an explanatory diagram showing a case where the second embodiment of the present invention is applied to a screw.

FIG. 3 is an explanatory diagram of the implementation portion of the same.

FIG. 4 is an explanatory diagram showing a case where the hook is mounted.

FIG. 5 is an explanatory diagram showing a conventional configuration.

[Explanation of symbols] 1 ... Screw 3 ... Screw part 5 ... Head 7 ... Vertebra connecting member 7R ... Rod part 9 ... Rod engaging part 11 ... Engagement groove 13 ... Fixing screw 15 ... Micro protrusion 19 ... Engagement groove 23 ... Rod engagement part 25 ... Bottom member 29 ... Micro protrusion 33 ... Block 35 ... Engagement groove 37 ... Micro protrusion 39 ... Vertebra connecting member 43 ... Rod part