TWI405555B - The attachment mechanism of the spinal fixation system - Google Patents

Abstract

A connection mechanism of a vertebral fixing system includes a bone fixing device having its near end as a connection end and its far end for fixing the spinal segment to be fixed, in which the connection end comprises a receiving portion; a first connecting rod having at least one end as a joining end, and the outer side of the joining end near the rod end is substantially spheral shaped and the rod end has a spheral bulge; a second connecting rod having at least one end as a joining end, in which the outer side of the joining end near the rod end is substantially spheral shaped, and the rod end has a spheral groove for matching with the spheral bulge of the first connecting rod; a first connecting cup having a connection mechanism at the cup opening edge, in which the inner side of the cup bottom is at least partially substantially spheral shaped, and the curvature of the spheral shape is slightly smaller or substantially equal to the curvature of spheral shape of the outer side of the joining end of the first connecting rod near the rod end for being universally joined with the spheral shape of the outer side of the first connecting rod near the rod end, and the cup bottom has a through hole for allowing the rod of the first connecting rod to extend outside from inside of the connecting cup; a second connecting cup having a connection mechanism at the cup opening edge, in which the inner side of the cup bottom is substantially spheral shaped, and the curvature of the spheral shape is slightly smaller or substantially equal to the curvature of the spheral shape of the outer side of the joining end of the second connecting rod near the rod end for being universally joined with the spheral shape of the second connecting rod near the rod end, and the cup bottom has a through hole for allowing the rod end of the second connecting rod to penetrate outside from inside of the connecting cup; and, a fastener for fixing the connecting cups with the receiving portion of the bone fixing device. The present invention is characterized by the connection mechanism at the cup opening edge of the first connecting cup and the connection mechanism at the cup opening edge of the second connecting cup are formed as a self connection.

Description

Linking mechanism of spinal fixation system

The invention relates to a connection mechanism of a spinal fixation system, in particular to a connection mechanism of an adjustable angle spinal fixation system.

In the spinal fixation surgery, the fixed rod is often used as an auxiliary fixation device, but because the spine is not in a straight line, the vertebrae are usually not parallel, for example, the lumbar vertebra is lordosis. Therefore, if the fixed rod that is originally in line is directly integrated with the multiple bone nails implanted in the vertebral joint to be fixed, it will force the spinal joints to be fixed not in the straight line to become in a straight line, and the original should not be parallel. The individual vertebrae to be fixed become parallel.

In order to avoid these shortcomings, the medical community has proposed various improved structures, such as:

1. Solve problems with angled screws such as US-5,176,679, US-5,196,014, US-5,257,994, US-5,466,238, etc.; for example US-5,176,679 utilizes angled pins designed to have specific angles ,), to solve the above-mentioned spine joints are usually not parallel problems. However, these methods are only suitable for the fixation of the vertebrae between a fixed rod and two bone nails (because the two points are in line), but not for a fixed rod and three or more bones above the bone. Fixed, because the three points are usually not in line. In addition, after the operation, the affected parts do not have dynamics such as extension, flexion, lateral bending, and axial torsion. Features.

2. Solve the problem with an angled connector, such as US-5,257,994, US-5,330,474, etc.; for example, US-5,257,994 utilizes locking blocks designed to have specific angles to solve the above-mentioned spine joints. Usually not parallel problems. However, these methods are only suitable for the fixation of the vertebrae between a fixed rod and two bone nails (because the two points are in line), but not for a fixed rod and three or more bones above the bone. Fixed, because the three points are usually not in line. In addition, after the operation, the affected parts do not have dynamics such as extension, flexion, lateral bending, and axial torsion. Features.

3. Solve problems with a universal connecting device, such as US-5,474,551, US-5,507,746, US-5,575,791, etc.; for example, US-5,474,551 utilizes a universal pad fixation device. Solving the above-mentioned vertebrae is usually not a parallel problem. However, these methods are only suitable for the fixation of the vertebrae between a fixed rod and two bone nails (because the two points are in line), but not for a fixed rod and three or more bones above the bone. Fixed, because the three points are usually not in line. In addition, after the operation, the affected parts do not have dynamics such as extension, flexion, lateral bending, and axial torsion. Features.

4. Solve problems with polyaxial screws, such as US approved patents US-5,520,690, US-5,531,746, ...US-7,186,2552, US-7,207,992, etc., and related publications in the United States Dozens of patent applications such as US-20010012937, US-20020111626, ..., US-20070161995, US-20070162006, etc. This is the current mainstream technology. These techniques basically utilize multi-axis screws (see the description of the details) to solve the problem that the above-mentioned vertebrae are usually not parallel.

However, the above methods are only applicable to the fixation of the vertebrae between a fixed rod and two bone nails (because the two points are in line), but not for a fixed rod and three or more bone bones. The knot is fixed because the three points are usually not in a straight line. Moreover, after the operation, the affected part does not have such an extension, flexion, lateral bending, axial torsion, etc. after the operation. Dynamic features.

5. Solve the problem with an artificial joint fixture, such as TW-I275380 (see the description of the case for details) to solve the problem that the above-mentioned vertebrae are usually not parallel.

These methods have dynamic functions such as extension, flexion, lateral bending, and axial torsion after surgery, but the design is poor in stability and has the risk of loosening. Sex also takes up a lot of space.

The inventor's Taiwan Patent TW-200936097 utilizes a ball and arc device to provide the spinal fixation rod with the above-mentioned dynamic functions such as extension, flexion, lateral bending and axial torsion. Functionality, but the patent utilizes an additional attachment means for attaching the first cup to the second cup such that the spinal fixation device would require an increased space, making the procedure less inconvenient and time consuming.

The invention cooperates with the ball arc groove of the joint end of the first connecting rod and the ball arc groove of the joint end of the second connecting rod, so that the two adjacent connecting rods can adjust the two adjacent links by the ball arc mechanism The purpose of the angle between the rods and the invention provides dynamic functions of extension, flexion, lateral bending, and axial torsion, and the present invention also employs a two-ball arc connection. The design of the self-linking between the cups is placed in the socket portion of the bone fixing device, so that the arc-shaped connecting cup body can be rotated relative to the receiving portion before fixing to adjust the placement angle of the fixing rod In order to meet the angle of lordosis of different patients; and the design of the arc-shaped connecting cup device in the socket of the bone fixing device does not occupy any space, and not only solves the Taiwan patent TW of the inventor -200936097 shortcomings, and improve the convenience of surgery.

It is an object of the present invention to provide a coupling mechanism for a spinal fixation system.

It is still another object of the present invention to provide a coupling mechanism for a spinal fixation system in which the coupling cup is self-joined.

Another object of the present invention is to provide a coupling mechanism for forming a universally coupled spinal fixation system using a ball arc structure.

It is still another object of the present invention to provide a coupling mechanism for an adjustable angle spinal fixation system.

Another object of the present invention is to provide a coupling mechanism for a spinal fixation system having a dynamic function.

It is still another object of the present invention to provide a coupling mechanism for a spinal fixation system that has a limited degree of control adjustment.

Another object of the present invention is to provide a coupling mechanism for a spinal fixation system having a ball-shaped connecting cup.

Still another object of the present invention is to provide a coupling mechanism for a spinal fixation system in which a coupling cup is rotatable in a receiving portion of a bone fixation device.

The joint mechanism of the spinal fixation system of the present invention comprises: a bone fixation device, the proximal end of which is a joint end, the distal end of which is used for fixing the vertebrae joint to be fixed, wherein the joint end has a receiving portion; the first connecting rod At least one end thereof is a joint end, the outer side of the joint end is substantially spherical arc-shaped, and the rod end has a ball arc bump; the second connecting rod has at least one end thereof being a joint end, and the joint end is near The outer side of the rod end is substantially spherical arc-shaped, and the rod end has a ball arc groove for engaging with the ball arc bump of the first connecting rod; the first connecting cup body has a cup end of the cup body a connecting mechanism, at least a portion of the inner side of the bottom of the cup is substantially spherically curved, and the curvature of the arc of the ball is slightly smaller than or substantially equal to the curvature of the ball at the outer end of the joint end of the first connecting rod near the rod end, and a ball joint of a joint end of the first connecting rod near the rod end is universally coupled, and a bottom of the cup has a through hole for allowing the rod end of the first connecting rod to pass out from the inside of the connecting cup to the outside; a second connecting cup body, the cup end of the cup body has a connecting mechanism, At least a portion of the inner side of the bottom of the cup is substantially spherically curved, and the curvature of the arc of the ball is slightly smaller than or substantially equal to the curvature of the ball at the outer end of the joint end of the second connecting rod near the rod end for use with the second connecting rod The ball end of the joint end near the rod end is universally coupled, and the bottom of the cup body has a perforation for allowing the rod end of the second connecting rod to pass out from the inside of the connecting cup body to the outside; and a holder And the connecting portion for fixing the connecting cup body to the bone fixing device; the connecting mechanism of the cup end of the first connecting cup body and the cup end of the second connecting cup body The machine constitutes a self-contained connection.

The self-linking of the connecting cups is connected to each other by a cup end connection mechanism of the first connecting cup and a cup end connecting mechanism of the second connecting cup to form a complete cup, thereby reducing the The size and structural complexity of the attachment mechanism of the fixed system further simplifies the complexity of the operation.

The connecting cup body may have a ball arc structure (refer to FIG. 1a), and the connecting cup body may be rotated in the receiving portion of the bone fixing device before being placed on the receiving portion of the bone fixing device but not fixed. To adjust the angle.

The self-linking of the connecting cups may be any conventional connection method such as a snap-fit connection, a screw connection, a lock connection, a snap connection or a node connection (please refer to FIGS. 4c and 4d).

The shape of the perforation of the connecting cup body is not limited, but a round hole is preferred, and the radius of the round hole is slightly larger than or equal to the radius of the round rod end of the connecting rod, so as to be slightly larger than the round rod of the connecting rod. Preferably, the end radius is such that the connecting rods can rotate universally in the perforations, and the size of the perforations can also limit the angle of rotation of the connecting rods.

In the above connecting rods, the two ends of the connecting rods may be combined ends or only one end of the connecting rods, wherein the two adjacent connecting rods may be combined with the ball arc grooves and the ball arc bumps of the connecting rods of the connecting rods. The two adjacent connecting rods are relatively rotatable (refer to FIG. 2b), and the purpose of adjusting the angle between the two adjacent connecting rods is achieved. The ball arc groove and the ball arc bump of the connecting rod of the connecting rod may have an adjusting plane, such as a tilt adjusting plane, an arc adjusting plane, etc., so that the two adjacent connecting rods can be separated by the inclined plane. The angle between the two adjacent connecting rods is restricted, so that the angle between the two adjacent connecting rods is not too large, so that the structure of the connecting rods cannot be reset or broken, thereby affecting the function of the spinal rod connecting mechanism.

The connecting rods may be integrally formed with the joint ends or integrated by a plurality of rods in a conventional combination (for example, snapping, screwing, locking, etc.). Among them, the connecting rods are similar to the conventional spinal rods, and are preferably round rods.

The outer ball arc at the end of the connecting rod near the end of the connecting rod and the ball arc at the inner side of the bottom of the connecting cup form a universal joint, so that the connecting rod can be rotated relative to each other by the arc surface of the ball in the connecting cup body. And to achieve the purpose of adjusting the angle between two adjacent connecting rods.

The bone fixation device may be a conventional bone nail (which may be a mono-axial screw or a poly-axial screw), a bone-like fixation device (such as a bone hook-hook, etc.). An auxiliary bone fixation device (for example, a side block or a side block or the like) or a rotary screw (see another Taiwan patent TW-99100438 by the present inventors) is preferably a bone nail or a rotating bone nail. The manner in which the bone fixation device and the connecting rod are combined may be a fixed manner of a conventional fixing rod and a bone nail, a bone hook or a side block, such as direct screwing or snapping.

The fixing device may be any conventional fixing device for combining with the receiving portion of the bone fixing device, wherein the bonding manner may be any conventional fixing manner, such as locking, snapping, screwing, etc. It is better.

The fixing of the connecting cup body is fixed to the connecting end of the bone fixing device, and can be any conventional fixing manner, such as screwing and fixing (conventional bone nail and rod screwing), locking fixing or card Fixed and so on.

The bone fixation device, the connecting rod, the connecting cup or the fixing device may be made of any approved or suitable orthopedic material, such as a metal material that can be implanted into the human body, such as an iron-based material stainless steel 316 LVM (stainless steel 316 LVM). ), titanium-based materials (such as Ti-6Al-4V), and cobalt-chromium-molybdenum alloys.

The connecting rods may further be provided with a connecting sleeve for connecting two adjacent connecting rods (please refer to FIG. 5), and the distance between the two adjacent connecting rods is adjusted by the connecting sleeve to match the different intervertebral spaces. Pitch.

Fig. 1a is an exploded perspective view showing a preferred embodiment of the connecting mechanism of the spinal fixation system of the present invention. The first connecting rod 310 and the second connecting rod 320 respectively pass through the first connecting cup body 110 and the second connecting cup body 120, because the outer side 312, 322 of the first connecting rod 310 and the second connecting rod 320 near the rod end is larger than The first connecting cup body 110 and the second connecting rod 320 will not slip out of the connecting cup body, and the first connecting cup body 110 and the second connecting cup body The first connecting rod 310 and the second connecting rod 320 are wrapped in the connecting cup body by the self-linking mechanism, and the ball arc of the first connecting rod 310 and the ball arc of the second connecting rod 320 The grooves 321 are relatively rotatable between the connecting rods by the ball arc mechanism of each other (please refer to FIG. 2b) to adjust the angle between the connecting rods. The size of the opening of the receiving portion 420 of the bone fixing device and/or the size of the perforation of the connecting cup body can limit the adjustable angle of the two adjacent connecting rods, so that the angle between the two adjacent connecting rods is not too large and cannot be reset or The structure of the connecting rod is destroyed, thereby affecting the function of the connecting mechanism of the spinal fixation system. The holder 200 fixes the coupling cup in the receiving portion 420. The outer side surface of the first connecting cup body 110 and the second connecting cup body 120 is a ball arc structure 150. After the connecting cup body is placed on the receiving portion 420, the receiving portion 420 can be rotated to adjust the angle. The outer side 312 of the first connecting rod 310 near the rod end and the outer side 322 of the second connecting rod 320 are ball arcs, so that the ball arc mechanism connecting the rods on the inner side of the bottom of the cup body can be made by the ball between each other The arc surface is relatively rotated to achieve the purpose of adjusting the angle between the two adjacent connecting rods.

Figure 1b is a combination of Figure 1a.

2a is a cross-sectional view showing a preferred embodiment of the coupling mechanism of the spinal fixation system of the present invention. The first connecting cup body 110 and the second connecting cup body 120 cover the first connecting rod 310 and the second connecting rod 320, and are placed in the receiving portion 420 of the nail, the ball arc bump 311 of the first connecting rod 310 and the first connecting rod 310 The ball arc grooves 321 of the two connecting rods 320 are relatively rotatable between the connecting rods by the ball arc mechanism of each other to adjust the angle between the connecting rods (please refer to FIG. 2b). The inclination angles of the inclined adjustment planes 313, 323 of the connecting rods are used to limit the angle between the two adjacent connecting rods in a limited manner.

Figure 2b is a schematic view showing the rotation of the connecting rod of Figure 2a.

Fig. 3 is a cross-sectional view showing a preferred embodiment of the coupling cup body in the coupling mechanism of the spinal fixation system of the present invention. After the first connecting cup body 110 is coupled to the second connecting cup body 120, the inner side surface thereof is a ball arc structure 160, so that the connecting rod can be rotated in the connecting cup body by mutually rotating the ball surface to achieve two phases. The purpose of the angle between the adjacent connecting rods.

4a, 4b, 4c, and 4d are schematic views showing a preferred embodiment of four types of connecting cups of the connecting mechanism of the spinal fixation system of the present invention. 4a shows that the first coupling cup 110 and the second coupling cup 120 are screwed together. FIG. 4b shows that the first connecting cup body 110 and the second connecting cup body 120 are coupled to each other by engagement. Fig. 4c shows that the connecting cup 100 is covered with a connecting rod by a side joint by a two-node joint 130 and is fixed by engagement. Fig. 4d shows that the connecting cup 100 is covered with a connecting rod by a side joint 140 and fixed by a snap fit.

Fig. 5 is a schematic view showing a preferred embodiment of the multi-segment connecting rod of the connecting mechanism of the spinal fixation system of the present invention. The first connecting rod 310 and the sleeve 360 are screwed together and adjusted in length, wherein the second rod 320 and the sleeve 350 are coupled to the first connecting rod 310 and the sleeve 360.

Fig. 6 is a schematic view showing a preferred embodiment of the joint mechanism of the spinal fixation system of the present invention assembled to the joint. The ball arc bumps of the first connecting rod 310 and the ball arc grooves of the second connecting rod 320 are relatively rotatable between the connecting rods by the ball arc mechanism of each other to adjust the angle between the connecting rods.

Figure 7 is a schematic view of another view of Figure 6.

100. . . Link cup

110. . . First connecting cup

120. . . Second connecting cup

130. . . Two-node link

140. . . Single node link

150. . . Ball arc structure

160. . . Ball arc structure

200. . . Holder

310. . . First connecting rod

311. . . Ball arc bump

312. . . Near the outer end of the rod

313. . . Tilt adjustment plane

320. . . Second connecting rod

321. . . Ball arc groove

322. . . Near the outer end of the rod

323. . . Tilt adjustment plane

330. . . Third connecting rod

340. . . Fourth connecting rod

350, 360. . . Sleeve

410. . . Screw section

420. . . Undertaking department

510, 520, 530. . . joint

Fig. 1a is an exploded perspective view showing a preferred embodiment of the connecting mechanism of the spinal fixation system of the present invention.

Figure 1b is a combination of Figure 1a.

2a is a cross-sectional view showing a preferred embodiment of the coupling mechanism of the spinal fixation system of the present invention.

Figure 2b is a schematic view showing the rotation of the connecting rod of Figure 2a.

Fig. 3 is a cross-sectional view showing a preferred embodiment of the coupling cup body in the coupling mechanism of the spinal fixation system of the present invention.

4a, 4b, 4c, and 4d are schematic diagrams showing a preferred embodiment of the connection type of the connecting cups of the spinal fixation system of the present invention.

Fig. 5 is a schematic view showing a preferred embodiment of the multi-segment connecting rod of the connecting mechanism of the spinal fixation system of the present invention.

Fig. 6 is a schematic view showing a preferred embodiment of the joint mechanism of the spinal fixation system of the present invention assembled to the joint.

Figure 7 is a schematic view of another view of Figure 6.

100. . . Link cup

110. . . First connecting cup

120. . . Second connecting cup

150. . . Ball arc structure

200. . . Holder

310. . . First connecting rod

312. . . Near the outer end of the rod

320. . . Second connecting rod

322. . . Near the outer end of the rod

410. . . Screw section

420. . . Undertaking department

Claims (6)

A joint mechanism for a spinal fixation system, comprising: a bone fixation device, the proximal end of which is a joint end, the distal end of which is used for fixing a spine joint to be fixed, wherein the joint end has a receiving portion; the first connecting rod, At least one end is a joint end, the outer side of the joint end is substantially spherical arc-shaped, and the rod end has a ball arc bump; the second connecting rod has at least one end thereof being a joint end, and the joint end is near the rod end The outer side of the ball is substantially spherical, and the rod end has a ball arc groove for engaging with the ball arc bump of the first connecting rod; the first connecting cup body has a connecting mechanism at the cup end of the cup body At least a portion of the inner side of the bottom of the cup is substantially spherically curved, and the curvature of the arc of the ball is slightly smaller than or substantially equal to the curvature of the ball at the outer end of the joint end of the first connecting rod near the rod end, and the first The ball end of the joint end of the connecting rod near the rod end is universally coupled, and the bottom of the cup body has a perforation for allowing the rod end of the first connecting rod to pass out from the inside of the connecting cup body to the outside; Connecting the cup body, the cup end of the cup has a connecting mechanism, the cup At least a portion of the inner side of the bottom portion is substantially arcuately curved, and the arc curvature of the ball is slightly smaller than or substantially equal to the curvature of the ball arc at the outer end of the joint end of the second connecting rod near the rod end for combining with the second connecting rod The ball arc on the outer side of the end near the rod end is universally coupled, and the bottom of the cup body has a perforation for allowing the rod end of the second connecting rod to pass out from the inside of the connecting cup body to the outside; and a holder And a connecting portion for fixing the connecting cup body to the bone fixing device; the connecting mechanism of the cup end of the first connecting cup body and the connecting machine of the cup end of the second connecting cup body are configured Self-linking. The connecting mechanism of the spinal fixation system according to claim 1, wherein the first connecting cup body and the outer side of the second connecting cup body are substantially spherical arc-shaped. The connection mechanism of the spinal fixation system according to claim 1, wherein the self-linking is a snap or screw. The joint mechanism of the spinal fixation system according to claim 1, wherein the first connecting rod has an adjustment plane beside the ball arc groove adjacent to the end ball arc bump and the second connecting rod joint end. The joint mechanism of the spinal fixation system according to claim 4, wherein the adjustment plane is a tilt adjustment plane. The joint mechanism of the spinal fixation system according to claim 1, wherein the bone fixation device is a bone nail or a rotating screw.