JP3172703B2 - Bone fixation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bone fixing device for connecting a pedicle attached to a bone to a reference shaft.

[0002]

2. Description of the Related Art A known device of this type has a large number of parts and requires a complicated structure. For example, in the invention of Japanese Patent Application Laid-Open No. 7-255739, a reference shaft, a bar serving as an intersecting arm, a continuous tool attached thereto, a bone screw corresponding to a pedicle, a collar for connecting the screw and a connecting tool are used. And a set screw for fastening the member.

[0003] Such a structure is necessary to give the pedicle various directions with respect to a reference axis. However, a complicated structure with many parts is not easy to manufacture and unsuitable for handling during surgery requiring a high speed. Therefore, a device that is easy to handle and compact as an implantable device in a living body is required.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned point, and an object of the present invention is to make it possible to connect shafts and pedicles irrespective of the positional relationship between them and to facilitate handling. Therefore, it is an object of the present invention to realize a bone fixing device having a high degree of freedom and a compact size.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a method in which an opening at one end is fitted to a shaft, is movable along the shaft, and is rotatably mounted around the shaft. A connector having a first coupling portion at one end for coupling with the connector, a screw leg which can be screwed into the bone at one end, and a second coupling portion at the other end for coupling with the connector; A bone anchoring device is constituted by the pedicle, the first coupling partner capable of coupling to the first coupling part of the connector, and the connector having the second coupling partner capable of coupling to the second coupling part of the pedicle, Attach to the axis of the insertion shaft of the first joint and the opening
The shaft center of the shaft A in the eccentric state and the shaft center of the shaft hole of the second coupling portion.
The axis of the wedging leg, the axis of the first coupling partner and the axis of the second coupling partner
The axes are also orthogonal as shown in FIG.
All is one that was taken means that in so that is stopped by each one of us screws.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A bone fixing device according to the present invention
And a pedicle 20 attached to a bone. The connector 10 and the pedicle 20 are connected with the connector 30 interposed therebetween.

[0007] The connector 10 has an opening 11 at one end.
The opening 11 is fitted to the shaft A, is movable along the shaft A, and is attached so as to be rotatable around the shaft. Therefore, the opening 11 has a groove-like opening shape that can be fitted to and removed from the shaft A.

The opening 11 in the illustrated embodiment is formed in a substantially U-shaped channel shape when viewed from the side, and a cylindrical fitting surface 12 adapted to the outer diameter of the shaft A having a circular cross section is provided at the back. ing. The rising 2 forming the opening 11
The pieces (U-shaped portions) are holding portions 13 and 14 of the shaft, and one of them has a screw hole 16 into which a male screw 15 to be fixed to the shaft A is screwed as a means for attaching (fixing or tightening) the shaft A. Provided. The illustrated male screw 15 (25, 35) is a hexagon socket head bolt type.

The connector 10 has a first connecting portion 17 for connecting the connector 30 at the other end. The connecting means may be either insertion or screwing, and in each case, it is optional whether the male and female are provided on the connector 10 side or the connector 30 side. However, the male side member is provided with a required length capable of adjusting the insertion length.

The first connecting means in the illustrated embodiment is a plug, and the plug shaft on the male side is connected to the opening 11.
Are provided integrally so as to protrude from the bulging portion 18 provided with the ridge. The axis of the insertion shaft of the first coupling portion 17 and the opening 11
Is orthogonal to the axis of the axis A in the state where it is mounted on the shaft.
Therefore, the female shaft hole is provided on the side of the connector 30 with the first coupling partner 37.
Is formed as

The pedicle 20 has a threaded leg at one end which can be screwed into the bone. The screw-in leg 21 is, for example, the tip 2
2 has a sharp, self-tapping screw-type thread at the base end 23, and a second coupling portion 2 for coupling with the connector 30.
7 at the other end. Also in this case, the connecting means is optional, and whether the second connecting portion 27 is female or male is freely determined.

[0012] The second coupling means in the illustrated embodiment is also plug the shaft hole serving as a female pedicle other end head section 2
8. The axis of the shaft hole of the second coupling portion 27 and the axis of the screwing leg 21 are orthogonal to each other. Therefore, connector 3
On the 0 side, a male shaft is formed. As a means for fixing or tightening the shaft portion inserted into the shaft hole, a screw portion 26 into which the male screw 25 is screwed is provided to stop the second coupling partner 47.

The first connector 17 of the connector 10 shown as an example is also compatible with the second connector 27 of the pedicle 20. That is, the first coupling portion 17 is not only insertable into the second coupling 27 but also fits exactly, and the relationship is the same as that of the second coupling partner 47 of the coupling 30 described below. Therefore, direct the connector 10 and the pedicle 20, it is also possible to bond and examples are also previously assumed in the present invention.

The above-described connector 30 has a first coupling partner 37 that can be coupled to the first coupling part 17 of the connector 10 and a second coupling partner 47 that can be coupled to the second coupling part 27 of the pedicle 20. . As described above, the first coupling partner 37 and the second coupling partner 47 can be inserted, screwed, and other means can be used. However, what to make the first coupling partner 37 depends on the relationship with the first coupling unit 17. What is determined as the second binding partner 47 depends on the relationship with the second binding unit 27. First binding partner
The axis of 37 and the axis of the second coupling partner 47 are also shown in FIG.
Are orthogonal to each other.

In the illustrated embodiment, the first coupling portion 17 is a plug-in shaft, so the first coupling partner 37 in this case is a shaft hole, and the second coupling portion 27 is a shaft hole, so the second coupling partner 47 is a plug-in shaft. Axis. Moreover, the insertion axis of the second connection partner 47 and the insertion axis of the first connection part 17 have the same shaft diameter, and the shaft hole of the second connection part 27 and the shaft hole of the first connection partner 37 have the same axis. The diameter is set respectively. A male screw 35 for fixing the first coupling portion 17 as a fixing or tightening means.
And a screw hole 36 for screwing the same.

In such a bone anchoring apparatus, when the pedicle 20 screwed into the bone is connected to the shaft A only by attaching the connector 10 thereto without using the connector 30 in the middle, the slide in the direction of the axis A is required. And rotation about the axis A, sliding in the direction of the first connector 17 and rotation around it. Using the connector 30, the first coupling portion 17 is connected to the first coupling partner 3
7 and the second coupling partner 47 is inserted into the second coupling portion 27 of the pedicle 20, the second coupling partner 47
A slight slide in the axial direction and a rotation about the same axis. See FIG.

The bone anchoring device according to the present invention is implanted in a living body to maintain the bones in a predetermined positional relationship, or to determine the positional relationship between the skull 51 and the spine (cervical vertebra) 52 as shown in FIG. Can be used in case. The device according to the invention, in which the axis A is then movably attached to the skull 51 by means of the attachment piece 53 (to obtain free movement during the procedure, not to move the head) and to the vertebral side And will be combined. Therefore, the components must be able to be positioned accurately and quickly, but the present invention fulfills this requirement to a high degree.

[0018]

Since the present invention is constructed and operates as described above, it has a remarkable effect that the pedicle can be accurately and quickly connected regardless of the positional relationship between the shaft and the pedicle.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a bone fixing device according to the present invention.

FIG. 2A is a side view of the apparatus of FIG. 1 as viewed from the pedicle side. (B) A bottom view of the pedicle viewed from below.

FIG. 3 is a perspective view showing the operation of the device of the present invention.

FIG. 4 is an explanatory plan view showing a state of attachment to a spine.

FIG. 5 is an explanatory side view showing the state shown in FIG.

────────────────────────────────────────────────── (5) References US Patent 5,254,118 (US, A) US Patent 5,543,260 (US, A) US Patent 5,688,275 (US, A) European Patent Application Publication 811356 (EP, A1) (58) Field surveyed (Int. Cl. ⁷ , DB name) A61B 17/56-17/92

Claims (3)

(57) [Claims] 1. A bone anchoring device for connecting a pedicle attached to a bone to a shaft serving as a reference, wherein the bone fixing device is fitted to the shaft at an opening at one end, and is movable along the shaft. A connector that is rotatably mounted about an axis and has a first coupling portion at the other end for coupling with the coupling, and a threaded leg that can be screwed into the bone at one end, for coupling with the coupling; A pedicle having a second coupling portion at the other end thereof, and a first
A first binding partner capable of binding to the binding portion and a second pedicle
A connector having a second coupling partner that can be coupled to the coupling portion, and an axial center of the insertion shaft of the first coupling portion;
Axis of axis A attached to mouth, axis of second joint
The axis of the hole and the axis of the screwed leg, the axis of the first mating partner and the
(2) The axes of the coupling partners are all orthogonal to each other, and
Rukotsu locking device all is stopped by each one of your screw parts. 2. The first connector of the connector is adapted to the second connector of the pedicle and connects the connector and the pedicle directly.
The bone fixation device according to claim 1, wherein the bone fixation device is connectable. 3. The bone fixation according to claim 1, wherein the first coupling portion and the second coupling partner are insertion shafts, and the second coupling portion and the first coupling partner are shaft holes having diameters adapted to the respective insertion shafts. apparatus.