JP2948148B2 - 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 fixing device for connecting a pedicle attached to a bone and a shaft serving as a reference for positioning in order to maintain the bone in a predetermined positional relationship.

[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 to 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 an operation requiring quick operation. 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 points, and has as its object to adjust the positional relationship between a shaft and a pedicle and then fix the shaft to the pedicle so that handling is easy and flexibility is improved. It is an object of the present invention to realize a bone fixing device which is large and can be made compact.

[0005]

In order to solve the above-mentioned problems, the present invention has a through hole 11 through which a shaft A passes, and a groove portion 12 which allows the hole diameter to be reduced. A portion 2 for attaching a connector 10 formed and formed with through holes 15 and 16 in separation portions 13 and 14 separated by a groove portion 12 and a pedicle 22 having screw legs 21 implantable in bone.
3 and has a locking means 24 which can be locked to one of the separation parts 13 and 14 formed by passing through the through holes 15 and 16 so as to surround the axis of the through hole. combining the pedicle mounting member 20 for mounting rotatably the shaft portion 25 provided on the mounting member 20
The locking means 2 is inserted into the through holes 15 and 16 of the connector 10 and the tightener 27 is screwed into the screw portion 26 at the tip.
Tighten the separating portions 13 and 14 at the 4 and緊締Ko 27, through hole
The peddy through which the shaft A passed through 11 passed through the through holes 15 and 16
The shaft A is fixed to the connector 10 by contacting the shaft portion 25 of the wheel mounting body 20 .

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described more specifically with reference to the illustrated embodiments. This device keeps the bone B in a predetermined positional relationship by being interposed between the axis A serving as a reference for positioning and the pedicle 22 attached to the bone B.

The connector 10 mounted on the shaft A is
A through hole 11 through which the shaft A can be moved so as to move along the groove, and a groove portion 12 for reducing the diameter of the hole is formed outward from the hole 11, and the separating portion 13 divided by the groove portion 12, 1
4, through holes 15 and 16 are formed substantially coaxially.

The through hole 11 communicates with the outside through a groove 12. Conversely, the groove 12 divides the tip of the through hole 11 of the connector 10 into two parts to form a pair of separation parts 13 and 14,
Further, the diameter of the through hole 11 is reduced by closing the groove by the width of the groove. The through holes 11, 16 penetrating the separation portions 13, 14 intersect with the through holes 11, and are orthogonal to each other in the embodiment shown in FIG. Also, as shown in the figure, the two holes 11, 15, 16 are close enough that the shaft A passed through the through hole 11 can come into contact with the constricted portion 28 of the shaft portion 25 of the pedicle mounting body 20 passed through the through holes 15, 16. (See FIG. 2).

The connector 10 is provided with locking means 24 for coupling with the pedicle mounting body 20. The pedicle attachment body 20 itself is a screw foot 21 which can be implanted in a bone.
Has an adjustable part 23 for mounting a pedicle 22 having a shaft 2 and a shaft 2 for coupling with the connector 10
5 at one end. The shaft portion 25 is rotatably inserted into the through holes 15 and 16, and the tip thereof penetrates through the connector 10, and a screw portion 26 is provided for attaching the tightener 27 there.

When the shaft portion 25 of the pedicle mounting body 20 is inserted into the through holes 15 and 16 of the connector 10, the contact portion between the separating portion 14 in the insertion direction and the base of the shaft portion 25 is provided. An engaging means 24 is provided. The locking means 24 stops the movement of the pedicle mounting body 20 in the axial direction, and in the illustrated example, the tapered inner surface 1 formed in one through hole 16.
6a and a tapered outer surface 25a on the side of the shaft portion 25 having substantially the same inclination.

The distal end of the tapered outer surface 25a is connected to the constricted portion 28 of the shaft portion 25. Therefore connector 10
When the tightener 27 is screwed into the screw portion 26 at the tip of the shaft portion that has penetrated further, the locking means 24 causes
Is pressurized, and the other separation piece 13 is pressed by the tightener 27, so that the groove 12 is narrowed, and the shaft A can be fixed to the connector 10 by clamping the shaft A from both sides.
The illustrated pedicle attachment body 20 is a pedicle 22
The pedicle 22 is moved along the mounting portion 23 so that the pedicle mounting body 20 can be clamped and stopped at an appropriate position by a stopper 29. it can.

In the bone anchoring apparatus of the present invention having such a configuration, when implanting the pedicle 22 in the bone B, the pedicle 22 can be rotated around the axis A and the axis 25 of the pedicle attachment body 20, and can be rotated. The distance from the axis A is adjustable.

For example, an example in which the device according to the present invention is used for fixing a cervical vertebra will be described with reference to FIGS. 7 and 8. Referring to FIG. 7, a bone (third vertebra c3 from the top in FIG. 7) V is implanted. The pedicle 22 and the shaft A are connected by the present apparatus.
As shown in FIG. 8, the direction and position of the pedicle 22 are different in each bone, but in this apparatus, the connector 10 is rotated around the axis A, and the direction of the pedicle attachment body 20 is adjusted by the shaft 25. Since the position of the pedicle 22 can be adjusted and moved on the mounting portion 23, the planting operation is also facilitated.

[0014]

Since the present invention is to act and the composition described above, and the axis A and connector 10 at the same time by installing a pedicle attachment body 20 to the connector 10 contact
It tactile, apparatus for perform the coupling is compact, collected
Great flexibility for adjusting the mounting position,
There is an effect that Ru easy der.

[Brief description of the drawings]

FIG. 1 is a side view of a shaft part showing a partial cross section of an embodiment of a bone fixing device according to the present invention.

FIG. 2 is a partial cross-sectional view as viewed from the direction of an axis A in the same.

FIG. 3A is a front view of a connector. (B) The longitudinal sectional view same as the above. (C) Transverse sectional view of the same.

FIG. 4 is a plan view of the pedicle attachment body.

FIG. 5 is a side view of the same.

FIG. 6 is a perspective view showing an assembled state.

FIG. 7 is an explanatory sectional view showing a use state.

FIG. 8 is an overall perspective view of the same.

Claims (3)

(57) [Claims] 1. A through-hole (11) through which a shaft (A) passes is formed, and a groove (12) that allows the diameter of the hole to be reduced is formed outward from the hole (11), and separated portions (13, 14) separated by the groove (12). The connector 10 has through holes 15 and 16 formed therein, and a portion 23 for attaching a pedicle 22 having screw legs 21 which can be implanted in bone, and is formed by passing through the through holes 15 and 16. And a pedicle mounting body 20 having a locking means 24 that can be locked to one of the separated portions 13 and 14 and rotatably mounted around the through-hole axis. Shaft 2
5 is inserted into the through-holes 15 and 16 of the connector 10, and the tightening means 27 is screwed into the threaded portion 26 at the tip to tighten the separating portions 13 and 14 with the locking means 24 and the tightening member 27.
The shaft A passed through the through hole 11 is
A bone fixing device that is in contact with the shaft portion 25 of the dickle attachment body 20 and fixes the shaft A to the connector 10. 2. The locking means 24 includes a tapered inner surface 16a formed in one of the through holes 16 and a tapered outer surface 2 of a pedicle mounting body 20 having an inclination substantially equal to the tapered inner surface 16a.
2. The bone anchoring device according to claim 1, wherein the bone anchoring device comprises: 3. The bone according to claim 1, wherein the through-hole 11 and the through-holes 15 and 16 partially overlap each other, and have a structure in which the shaft A and the shaft portion 25 of the pedicle mounting body 20 can come into contact with each other. Fixing device.