JP2500213B2 - Surgical tools - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surgical instrument for cutting and separating biological tissue by ultrasonic vibration.

[0002]

2. Description of the Related Art Conventionally, a surgical scalpel has been used for cutting and separating biological tissue, particularly hard bone tissue and cartilage tissue, but the efficiency of the cutting work is poor and it takes a long time, which requires a great deal of labor for the operator. However, there is a drawback in that it requires a high level of technique for cutting and separating.

A large number of surgical tools utilizing ultrasonic waves have also been developed. Surgery for ultrasonically vibrating an operating portion connected to an ultrasonic vibration source to crush the contacted biological tissue and suction removal. Surgical tools (for example, Japanese Patent Publication No. 47-3919)
No. 7), and surgical tools having a saw-like operating portion connected to an ultrasonic vibration source, which are developed for cutting and separating hard and soft biological tissues.
However, a surgical tool that oscillates, emulsifies, and removes the surface layer of soft biological tissue by ultrasonic vibration using a vibrating body that has a flat operating section that is perpendicular to the vibration direction Since the tissue is crushed by the action of hitting the surface layer of the biological tissue by vibration, it is difficult to cut the tissue into the biological tissue by cutting it into the biological tissue and it is not suitable for cutting harder biological tissue. there were.

A surgical instrument for cutting and separating biological tissue by means of a saw-like operating portion that vibrates ultrasonically is devised in the shape of the operating portion in order to improve the cutting efficiency, but it is necessary for cutting. Friction heat is generated between the operating section and the biological tissue to be cut due to the amplitude of the operating section of about 30 to 50 μm, and even in the case of the operating section, for example, a titanium alloy having excellent thermal conductivity, a surface temperature of several hundred degrees is reached. The tissue that has reached and has been cut is carbonized. Further, the operation portion having a thin wall such as a blade shape may be deteriorated by frictional heat and may be crushed.

Further, when microscopically observing the operation of cutting hard tissue by ultrasonic vibration, as shown in FIG. 8A, when cutting the bone (21) in the vibration direction of arrow B,
Although the fine fractured portion (24) is continuously generated by the shearing force at the tip portion (22) of the blade-shaped vibration transmitting tool (20), it becomes a macroscopically cut shape. FIG. 8B is a view of the blade-shaped vibration transmitting tool (20) seen from the front direction. When finely shearing a bone with a thin blade shape, the angle of the tip portion (22) of the vibration transmitting tool (20) is shown. Although the shearing force increases as the angle becomes sharper, a degenerated layer (25) other than the cut portion is widely generated, and there is a drawback that the bone regeneration state of the cut portion after the operation deteriorates.

When the cutting width is wide, the thickness of the blade-shaped vibration transmitting tool (20) is increased. As a result, the contact area of the side surface becomes too large and the cutting speed is reduced, and the frictional heat generated by ultrasonic vibration is increased. Could occur in large quantities.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the conventional surgical tools, and heats the horn to carbonize biological tissue or deteriorate the horn itself. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problem and to provide a surgical instrument having a shape suitable for fine work while minimizing the degeneration of the cut portion.

[0008]

That is, the present invention is a vibration transmitter for a surgical operating apparatus for cutting and separating living tissue by ultrasonic vibration, wherein the vibration transmitter has a mechanical ultrasonic wave in the vicinity of the tip. It has a working surface provided with a plurality of grooves having an angle with respect to the vibration direction, has an irrigation liquid passage inside, and the irrigation liquid passage is located on the working surface or stops near the tip. Is connected to one or more irrigation ejection holes located on the base side surface of the work surface, and the edge portion of each work surface sandwiched by the grooves of the work surface has a rake angle. It is a surgical instrument characterized in that

The present invention will be described in detail below with reference to the drawings. FIG. 1 is a view showing a surgical instrument according to an embodiment of the present invention.

The vibration transmitting tool (1) is connected to the vibrating body having the same resonance frequency by the connecting screw (4), and ultrasonic vibration generated by applying high frequency power having the resonance frequency to the vibrating body is applied to the tip work. Communicate to biological tissue via surface (3). Connection between the vibrating body and the vibration transmitting tool (1) can be performed by any method other than screw connection, such as welding or crimping, as long as it is made on the antinode surface of ultrasonic vibration, and is not particularly limited. The vibrating body may be an electrostrictive type or magnetostrictive type vibrating element having an irrigation liquid passage therein and is not particularly limited, but it is preferable to use a BLT vibrating element having excellent electrical and mechanical conversion efficiency. . The ultrasonic vibration generated in the vibrating body is transmitted and expanded by the vibration transmitting tool (1) and has the maximum amplitude on the work surface (3), but the amplitude reaches 100 to 200 μm. If the amplitude is increased more than this, the cutting speed will be higher than it seems, but problems such as charring of the cutting part, durability of the work surface (3) and cutting noise will occur, so the upper limit amplitude should be 200 μm. Although preferred, it is not particularly limited technically. Further, the resonance frequency is preferably 20 to 45 KHz, and 2
Especially good vibration is obtained at 2 to 40 kHz.

The irrigation liquid passage (7) continues from the vibrating body to the vibration transmitting tool (1), and the irrigation liquid jetting located near the work surface (3) in front of the vibration transmitting tool (1) passes through the inside thereof. It is opened with a hole (2). 2 and 3 are enlarged views in the vicinity of the work surface (3) showing the opening positions of the irrigation liquid ejection holes (2). In the example shown in FIG. 2, the irrigation liquid passage (7) is located on the work surface (3). It is branched into two at the root side, and the branch passage (7 ′) forms an angle of 5 to 10 ° with respect to the long axis direction of the vibration transmission tool (1).
As shown in (a), the irrigation liquid ejection holes (2) are open on both side surfaces on the root side of the work surface (3),
The structure is such that the irrigation liquid can be sprayed toward the work surface (3) during ultrasonic vibration. On the other hand, in the example of FIG. 3, the irrigation liquid ejection holes (6) are directly opened to the work surface (3) to prevent the generation of frictional heat due to the vibration of the work surface (3). The opening position of the irrigation liquid ejection hole is
Depending on the durability of the working part (3) against vibration and the like, either the vicinity of the root side of the working surface or the working surface (3) may be used. The opening diameter of the irrigation liquid ejection hole (2) is not particularly limited, but it is preferably smaller than the diameters of the irrigation liquid passage (7) and the branch passage (7 ').

FIG. 4 is a view showing an example of the direction of grooves provided on the work surface. The direction of the groove can be selected according to the hardness of the bone to be cut and how to apply force during operation. FIG.
The groove (8) shown in (a) is perpendicular to the vibration direction of ultrasonic waves, that is, the long axis direction of the vibration transmission tool (1), and is long in the long axis direction when cutting a curved bone. Compared to the parallel grooves, the bite into the cutting portion is large, and the operator is less likely to slip the work surface (3) in a direction other than the cutting direction or cut another portion by mistake. On the other hand, FIG.
When creating a curved cutting line, the groove (9) shown in (b) has an acute angle with respect to the vibration direction so that the groove (9) can be easily moved left and right during cutting. Become.
The groove shape of the work surface is not limited to a straight line, but may be a curved line, and can be selected depending on the object to be cut.

FIG. 5 shows an example in which the work surface (10) has an angle α with the vibration direction. Since the operator can use the vibration transmitting tool (1) while standing it at an angle α, it is narrow. It is also suitable for cutting parts. The angle is not particularly limited, but is preferably 5 to 45 °.

FIG. 6 shows a plurality of work surfaces (3) (12) (1).
3), each working surface has groove pitch, depth,
The width is different from each other, and an appropriate work surface can be selected with one vibration transmission tool (1) according to the cutting target and the cutting shape, and there is an advantage that it is not necessary to prepare a plurality of vibration transmission tools. .

FIG. 7A shows a microscopic process for cutting the bone (15) of the vibration transmission tool (1) of the present invention which vibrates in the direction of arrow A. The work surface (10) sandwiched by the groove (5) has an angle with respect to the vibration direction (A), and a shearing force is generated by the vibration of the work surface (10) to cause a fine fracture portion (14). Occurs, and macroscopically shows the action of cutting the bone (15). The angle of the working surface (10) at this time is 1 to 30 °, preferably 5 to 10 °. Due to the effect of this angle, even if the work surface (10) is not pressed against the bone surface by the mechanical force of the operator other than the vibration, the work surface (10) automatically bites into the bone due to the vibration and shear fracture. Cause As a result, the force for pressing down the work surface (10) is reduced, and the degenerated layer (16) becomes thin as shown in FIG. 7 (b), which is effective for bone regeneration after surgery. The depth of the groove (5) depends on the size of the fine fracture part (14) and is 0.01 to 0.5.
mm, preferably 0.05 to 0.3 mm, but not particularly limited. The width of the groove is preferably 0.1 to 0.5 mm. The number of grooves on the work surface is not particularly limited,
The tip shape of the vibration transmitter (1) having the work surface (3) is
It may be block-shaped or dome-shaped, and can be appropriately selected depending on the approach direction and size of the cutting portion.

Further, as shown in FIG. 7 (a), the edge portion (18) of the work surface (3) sandwiched by the groove (5) has a rake angle, and the angle is not particularly limited, but this shape By having, it is possible to control the size of the fine fracture portion (14) due to the shearing force and adjust the surface condition after cutting. The cross-sectional shape of the edge portion (18) may be a curved line or a straight line, and the cross-sectional shape and the rake angle of the two edge portions on both sides may be the same or different.

[0017]

According to the present invention, the work of cutting and separating biological tissue, particularly hard tissue such as bone, by ultrasonic vibration does not require technical skill and is quicker than the conventional surgical tools. It can be cut and separated, and it prevents alteration of the bone cell tissue around the cutting surface due to frictional heat and degeneration of tissue due to mechanical compression to promote postoperative healing and further improve the operator's safety and vision. It is suitable as a surgical tool that can perform a wide range of precise cutting work without interference and can be used continuously for a long time with high amplitude.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic structure of a surgical instrument according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a vibration transmission tool tip portion showing an example of the opening position of an irrigation liquid ejection hole.

FIG. 3 is an enlarged view of a tip portion of a vibration transmitter showing another example of the opening position of the irrigation liquid ejection hole.

FIG. 4 is a diagram showing an example of a groove shape on a work surface.

FIG. 5 is a diagram showing an example in which a work surface has an angle with a vibration direction.

FIG. 6 is a diagram showing an example of a vibration transmitter having a plurality of work surfaces.

7A and 7B are views showing a microscopic process in cutting by the vibration transmitting tool of the present invention, FIG. 7A is a side sectional view, and FIG. 7B is a front sectional view.

FIG. 8 is a diagram showing a microscopic cutting state of a conventional surgical instrument by ultrasonic vibration, (a) is an example of a blade-shaped vibration transmitting tool perpendicular to the vibration direction, and (b) is parallel to the vibration direction. It is an example of a simple blade-shaped vibration transmission tool.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration transmission tool 2, 6 Irrigation liquid ejection hole 3, 10, 12, 13 Working surface 5, 8, 9 Groove 7 Irrigation liquid passage 14, 24 Micro fracture part 16, 25 Denatured layer 18 Edge part 20 Blade shape vibration transmission tool

Claims (3)

(57) [Claims] 1. A vibration transmitter for a surgical apparatus for cutting and separating living tissue by ultrasonic vibration, wherein the vibration transmitter has a plurality of angles in the vicinity of its tip with respect to the mechanical vibration direction of ultrasonic waves. Has a working surface provided with a groove, and has an irrigation liquid passage inside , and the irrigation liquid passage is located on the working surface, or is stopped at a portion near the tip and is on the root side surface of the working surface. Which are respectively connected to one or a plurality of irrigation ejection holes, and which are located in the respective work surfaces sandwiched by the work surface grooves.
A surgical instrument wherein the edge portion has a rake angle . 2. The surgical instrument according to claim 1, wherein the surgical instrument has a plurality of types of working surfaces having different groove pitches and depths . 3. The surgical instrument according to claim 1, wherein the work surface has an angle with respect to the mechanical vibration direction of the ultrasonic waves.