JP2001149392A - Vertebral arch spacer for expanding spinal canal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertebral arch spacer for dialating the spinal canal which is excellent in initial fixability and difficult to break a suture. SOLUTION: The vertebral arch spacer for dialating the spinal canal by inserting the spacer between divided vertebral arches, comprises side surfaces 1 and 2 in contact with each divided vertebral arch, a through hole 3 for passing the suture opened in the side surfaces 1 and 2, and a tightening surface 5 having lattice-like grooves formed therein and the suture tightened thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertebral column spacer for spinal canal enlargement.

[0002]

2. Description of the Related Art Surgical treatment is one of the treatments for ossification of the posterior longitudinal ligament, ossification of the yellow ligament, spinal canal stenosis, and the like.
In this method, the spine is deployed posteriorly, and the vertebral arch is cut off at one side, or the spinous process is split. In the former method, a groove is formed in the contralateral side of the lamine, the inside of the vertebral cortex is thinned, and the vertebral column is turned to enlarge the spinal canal. In the latter method, a groove is made in the lateral part of the bilateral lamine, the vertebral spine is similarly inverted, and the spinal canal is enlarged. Thereafter, the lamine spacer is sandwiched and fastened and fixed with a suture such as a wire, a synthetic thread, or a silk thread. This is intended to expand and fix the stenotic spinal canal.

[0003]

However, a spacer having a dense and smooth surface, such as a spacer made of crystallized glass, is not easily hooked on the surface of the fastened and fixed suture, and thread slippage is likely to occur. For this reason, the initial fixation of the spacer is poor, and the spacer moves to absorb the surrounding bone, which may further deteriorate the fixation. In addition, the movement of the spacer may cause the suture used for fixation to be cut, which may cause a drop into the spinal canal. Under such circumstances, a spacer having a concave portion for preventing thread slippage has been proposed, but since the fastening method differs depending on the surgical technique, this may not function sufficiently.

[0004] It is an object of the present invention to provide a lamine spacer for dilatation of a spinal canal which has good initial fixation and is hard to cut a suture.

[0005]

SUMMARY OF THE INVENTION As shown in FIG. 1, a vertebral canal dilation spacer according to the present invention is inserted between divided lamines to expand a spinal canal. A bow spacer, which is formed with side surfaces 1 and 2 in contact with each of the divided vertebrae, through holes 3 opened in both side surfaces 1 and 2 for inserting a suture, and a lattice-shaped groove 4; And a fastening surface 5 on which the fastening is performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The vertebral canal dilatation spacer of the present invention has a lattice-shaped groove formed on the fastening surface, so that the suture can be used regardless of the fastening method used. In any of the grooves. For this reason, the displacement or cutting of the suture hardly occurs, and the initial fixability of the vertebral arch and the spacer can be improved.

[0007] Further, a through hole for inserting a suture is formed in the direction of enlargement of the vertebra, and the vertebra on both sides of the spacer can be firmly fixed with the suture.

The spacer of the present invention may be a ceramic material such as alumina, zirconia, hydroxyapatite, calcium phosphate, tetracalcium phosphate, a glass material having bioactivity such as calcium phosphate glass, calcium phosphate crystallized glass, stainless steel, titanium,
It can be made of a metal material such as a titanium alloy. Especially hydroxyapatite, calcium phosphate,
It is preferable to use a bioactive material such as tetracalcium phosphate, calcium phosphate-based glass, or calcium phosphate-based crystallized glass, since direct bonding with natural bone becomes possible.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.
FIG. 1A is a perspective view showing an embodiment of the spacer for spinal canal enlargement of the present invention, and FIG. 1B is a sectional view thereof.

The spacer 10 is a block made of a substantially trapezoidal calcium phosphate crystallized glass that expands from the spinal canal side to the back side. Openings 3a, 3b of the through-hole 3 are provided in the central portions of both side surfaces 1, 2. The fastening surface 5 of the suture on the back side is flat, and a lattice-shaped groove 4 is formed over the entire fastening surface 5. Here, the groove 4 has a width of 0.05 to 5 mm and a depth of 0.0
It is preferable that the size is 5 to 5 mm and the interval between the grooves is about 0.05 to 5 mm. The grooves need not necessarily be orthogonal to each other. Further, the interval between the grooves and the size of the grooves may not be constant.

Next, a method of using the spacer having such a configuration will be described with reference to FIG.

First, the spinal canal is vertically divided and enlarged. Next, insertion holes for the suture A are formed in the vertically split lamine portions 20, 21, respectively.

Subsequently, after the suture A is passed through the insertion holes of the lamine portions 20 and 21 and the through hole 3 of the spacer 10, the side surfaces 1 and 2 of the lamine 20,
The spacer 10 is inserted so as to be in contact with 21. Thereafter, the suture A is inserted into the appropriate groove 4 of the fastening surface 5 of the spacer 10.
And fix the spacer 10 by fastening it on the fastening surface 5.

The lamine spacer of the present invention is not limited to the above-described shape, and various shapes can be selected without impairing the features of the present invention.

[0015]

As described above, when the spinal canal dilatation spacer of the present invention is used, the initial fixation of the spacer is good and the suture is hard to be cut. Therefore, even if the spacer has a dense and smooth surface, such as a crystallized glass spacer, the spacer can be prevented from falling off, moving, and dropping.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a spacer for spinal canal enlargement of the present invention.

FIG. 2 is an explanatory view showing a use state of a spacer for spinal canal enlargement of the present invention.

[Explanation of symbols]

 Reference Signs List 10 spacer for spinal canal enlargement 1, 2 side surface 3 through hole 3a, 3b opening 4 groove 5 fastening surface A suture

Claims (1)

[Claims] 1. A laminoplasty spacer for dilatation of a vertebral canal, which is inserted between divided lamines to enlarge a spinal canal, wherein a suture is opened on a side surface in contact with each of the divided lamineae and on both side surfaces. A lamine spacer for spinal canal enlargement, comprising a through hole for insertion, a lattice-shaped groove, and a fastening surface for fastening a suture.