JP2025122310A - Biological suturing device - Google Patents

Abstract

[Problem] To facilitate the release of sutures. [Solution] A biological suturing device comprising a suture insertion puncture needle 1 for feeding a suture 50 into the body and a suture insertion puncture needle 2 for withdrawing the suture from the body, arranged in parallel, and an operating section 40 including an operating rod 20 for inserting and removing a long, linear snare loop 10 formed at its looped tip into and from the body, wherein the snare loop 10 extends in a loop shape in a direction approximately perpendicular to the downward vertical direction and has an annular suture engagement section 14 twisted at the loop tip so that the intersecting portions do not come into contact, and wherein a suture 50 having higher rigidity than the snare loop 10 is inserted into the suture engagement section 14 and pushed out of the operating rod 20, whereby the suture 50 is pushed into the intersecting portion and released from the suture engagement section 14 of the snare loop 10. [Selected Figure] Figure 8

Description

The present invention relates to a biological suturing device used, for example, to suture the stomach wall and abdominal wall of a patient in order to temporarily secure the stomach wall to the abdominal wall. In particular, the present invention relates to a biological suturing device that can easily remove a suture that has been fed into the body using a suture-pulling puncture needle and held in a snare loop from the snare loop.

Typically, a biological suturing device is used, for example, when endoscopically forming a gastrostomy to allow food to flow into the stomach, to suture the patient's stomach wall to temporarily secure it to the abdominal wall. A conventional biological suturing device, shown in Figure 9(a) and elsewhere, is used to temporarily secure a patient's abdominal wall 101 and stomach wall 102 together. It includes a suture insertion needle 1 that is inserted from outside the body so that its tip reaches the stomach and introduces a suture 50 into the stomach, a suture withdrawal needle 2 that withdraws the suture 50 introduced into the stomach by the suture insertion needle 1, a plate-shaped connecting member 3 that positions the suture insertion needle 1 and the suture withdrawal needle 2 in parallel, and an operating unit 40 that inserts and removes a snare loop 10, whose long, loop-shaped tip is inserted and removed from a cylindrical operating rod 20 that can be inserted and removed from the outside.

The suture insertion puncture needle 1 is cylindrical and has an internal passageway passing through it in the axial direction for feeding the suture 50 from outside the body into the body, with an inlet connector 4 attached to its proximal end. The suture withdrawal puncture needle 2 is cylindrical and has an internal passageway passing through it in the axial direction for withdrawing the tip of the suture 50 introduced into the stomach from inside the body to outside the body, with an inlet connector 5 attached to its proximal end.

The operating unit 40 comprises a snare loop 10, a long material with a loop-shaped distal end, a cylindrical operating rod 20 that passes through the snare loop 10, and a gripping portion 30 attached to the rear end of the snare loop 10 for the operator to grasp with their hand. The snare loop 10 is an elastic wire, such as a long, solid stainless steel wire, with an open loop formed at its distal end for engaging near the distal end of the suture 50 and pulling the suture 50, and is provided with a suture engaging portion at its distal end for clamping and holding the suture 50. For example, as shown in Figures 10(a) and (b), the snare loop 10 is made of a long stainless steel wire and has a three-dimensional loop shape (heart or circular) at its tip, protruding from the tip and provided with a U-shaped suture engagement portion 15 with an inner diameter substantially the same as the diameter e of the snare loop 10 and a depth Z, which is shaped so that when inserted into the stomach, it extends in a direction substantially parallel to the stomach wall and abdominal wall (a direction substantially perpendicular to the downward vertical direction). Furthermore, the snare loop 10 can be elastically deformed by narrowing the loop-shaped portion so that it can pass through the internal passage of the suture withdrawal puncture needle 2.

The biological suturing device configured as above allows a doctor to suture the stomach wall and abdominal wall by carrying out the following steps.
(A) A first step in which a suture insertion puncture needle 1 and a suture withdrawal puncture needle 2 connected by a connecting member 3 are pierced from outside the body through the abdominal wall 101 and the stomach wall 102, so that the tips of the suture insertion puncture needle 1 and the suture withdrawal puncture needle 2 are lined up and open into the stomach, and then, as shown in Figure 9(a), a suture 50 is inserted from the entrance connector 4 to the rear end position of the suture insertion puncture needle 1, and a snare loop 10 is inserted from the entrance connector 5 into the suture withdrawal puncture needle 2, so that the loop portion of the snare loop 10 is extended toward the suture insertion puncture needle 1 in a direction approximately parallel to the stomach wall and abdominal wall (horizontal direction).
(B) In the first step, with the loop portion of the snare loop 10 extended from the tip of the suture withdrawal puncture needle 2 in a direction approximately parallel to the stomach wall and abdominal wall, the suture 50 is protruded from the suture insertion puncture needle 1 so as to pass through the loop portion of the snare loop 10 extending laterally from the suture withdrawal puncture needle 2, as shown in Figure 9(b).
(C) As shown in Figure 9(c), the third step is to use the operating part 40 to pull out the snare loop 10 from the inlet nozzle 5 of the suture withdrawal puncture needle 2, so that the end of the loop hooks the suture 50 and pulls it out of the body.

As shown in FIG. 10( a ), the details of this third step are as follows: a suture 50 is inserted downward from the suture insertion puncture needle 1 into the opening of the snare loop 10, which has a U-shaped suture engagement portion 15 at its tip and is in a loop shape that is spread out laterally, from below the suture withdrawal puncture needle 2; and then the snare loop 10 is pulled out, so that, as shown in FIG. 10( b ), the suture 50 is drawn into the U-shaped suture engagement portion 15 at the tip of the snare loop 10, and is hooked by retaining and engaging with the suture engagement portion 15, which has a U-shaped opening with a dimension e that is approximately the same as the diameter of the suture 50; and the snare loop 10 is then pulled out from within the suture withdrawal puncture needle 2.
(D) Next, the doctor pulls out the suture insertion needle 1 and the suture withdrawal needle 2 from the body and knots the suture together, thereby suturing the abdominal wall 101 and the stomach wall 102 together.

Note that the following patent documents 1 and 2 are examples of documents that describe technology related to the aforementioned biological suturing device.

Japanese Patent Application Laid-Open No. 2007-50200 Japanese Patent Application Laid-Open No. 2007-151615

Generally, when performing a procedure to temporarily fix a patient's stomach wall to the abdominal wall using the above-mentioned operation, it may be necessary to first hold and engage the suture 50 in the suture engagement portion 15 and then release the suture 50. However, the conventional biosuturing device described in Patent Document 1 clamps and holds the suture 50 in the U-shaped suture engagement portion 15, which makes it difficult to release the suture 50 from the suture engagement portion 15.

Furthermore, the biological suturing device described in Patent Document 2 describes a technique in which a highly rigid shape-memory wire, which is tied to a suture and has been curved to form an arc, is inserted laterally into a snare loop hanging vertically downward, thereby engaging and gripping the tip of a suture insertion needle with the shape-memory wire, and then the engaged suture insertion needle is pulled out, pulling the suture connected to the shape-memory wire out of the stomach. The technology described in Patent Document 2 describes a technique in which the suture engagement portion at the tip of the snare loop is configured as a guide portion (annular portion) formed by rotating a thin wire once. However, as described in paragraph 0038, this guide portion engages with the suture insertion needle and the shape-memory alloy wire to firmly grip them. Other effects are not described, nor is there any suggestion of the challenges or techniques involved in releasing the shape-memory wire after it has been engaged and gripped.

In view of these issues, the present invention aims to provide a biological suturing device that allows for easy removal of a suture from a snare that has been inserted into the body through a suture withdrawal puncture needle.

In order to achieve the above object, the present invention provides a biological suturing device comprising an operating section including a snare loop made of a single stainless steel wire having a predetermined rigidity and a long, wire-like tip formed into a loop shape, and a cylindrical operating rod into which the snare loop can be inserted and removed; a suture insertion puncture needle having an internal passage passing therethrough in the axial direction for feeding a suture into a body; a suture withdrawal puncture needle arranged in parallel to the suture insertion puncture needle and having an internal passage passing therethrough in the axial direction for withdrawing the tip of the suture from the body, and into which the operating rod can be inserted and removed; and a connecting member for arranging the suture insertion puncture needle and the suture withdrawal puncture needle side by side,
the snare loop extends in a loop shape from the tip of the operating rod in a direction substantially perpendicular to the vertically downward direction when protruding from the cylindrical operating rod, and has an annular suture engaging portion in which the tip of the loop shape is twisted at an angle of 30 degrees to less than 180 degrees within a range in which the intersecting portions do not come into contact with each other;
The first feature is that the suture has higher rigidity than the snare loop, and when the snare loop is inserted into the suture engagement portion of the snare loop and pushed out from the operating rod, the suture is pushed into the intersection portion and disengaged from the suture engagement portion of the snare loop.

The present invention also provides a surgical instrument comprising: an operating section including a snare loop having a long, linear tip formed into a loop shape; and a cylindrical operating rod into which the snare loop can be inserted and removed; a suture insertion puncture needle having an internal passage passing therethrough in the axial direction for feeding a suture into a body; a suture withdrawal puncture needle having an internal passage passing therethrough in the axial direction for withdrawing the tip of the suture from the body, and through which the operating rod can be inserted and removed, and arranged in parallel to the suture insertion puncture needle; and a connecting member for arranging the suture insertion puncture needle and the suture withdrawal puncture needle side by side,
the snare loop is made of a stainless steel solid wire set to a predetermined first diameter;
a biological suturing device formed so as to extend in a loop shape from a tip of the operating rod in a direction substantially perpendicular to a vertically downward direction when protruding from the cylindrical operating rod,
the suture is a long, resin-made single wire, and has a straight shape maintaining force that tends to maintain the straight shape when hanging down in an elongated shape in the vertically downward direction, and the straight shape maintaining force is set by a difference in diameter between the suture and the first diameter of the snare loop being 1.5 to 5 times larger,
The second feature of the snare loop is that it has a circular suture engaging portion that protrudes from the tip of the loop, has an inner diameter that is set to a range of 1.5 to 5 times the diameter of the suture, and is twisted at an angle of 30 degrees to less than 180 degrees so that the intersections do not come into contact.

Furthermore, the present invention has a third feature in that, in the biological suturing device of the first or second feature, the snare loop has an annular suture engagement portion formed by a twist angle of 80 to 100 degrees; a fourth feature in that, in the biological suturing device of the first or second feature, the snare loop has an annular suture engagement portion formed by a twist angle of 170 to less than 180 degrees; a fifth feature in that, in the biological suturing device of the third feature, the suture engagement portion of the snare loop has an inner diameter set to a range of two to three times the diameter of the suture; and a sixth feature in that, in the biological suturing device of the fourth feature, the suture engagement portion of the snare loop has an inner diameter set to a range of two to three times the diameter of the suture.

The biological suturing device according to the first aspect of the present invention has a loop-shaped suture engagement section that extends from the tip of the snare loop in a direction approximately perpendicular to the downward vertical direction when the snare loop protrudes from the operating rod, and has a circular suture engagement section in which the tip of the loop is twisted so that the intersecting portions do not come into contact. When a suture with higher rigidity than the snare loop is inserted into the suture engagement section and the snare loop is pushed out, the suture is pushed into the intersecting portion and disengaged from the suture engagement section of the snare loop. This allows a suture that has been inserted into the snare to be easily removed from the snare.

The biological suturing device according to the second aspect of the present invention has a straightness maintaining force that tends to maintain the straightness of the suture when it is hanging down in a thin, elongated shape in the vertical direction, and this straightness maintaining force is set by a difference in diameter between the snare loop and the first diameter being 1.5 to 5 times larger, and the snare loop has an annular suture engaging portion that projects from the tip of the loop and has an inner diameter that is 1.5 to 5 times larger than the diameter of the suture, and is twisted at an angle of 30 degrees to less than 180 degrees so that the intersecting portions do not come into contact with each other,
Once inserted into the snare, the suture can be easily removed from the snare.

1A and 1B are diagrams illustrating the operation unit of the biological suturing device according to an embodiment of the present invention and the step of inserting a snare loop into a suture withdrawal puncture needle using the operation unit. 1A and 1B are diagrams for explaining the structure of a snare loop according to a first embodiment of the biological suturing device of the present invention. FIG. 2 is an enlarged view showing the tip portion of the snare loop according to the first embodiment. 10A and 10B are diagrams illustrating the structure of a snare loop according to a second embodiment of the biological suturing device of the present invention. FIG. 10 is an enlarged view showing the tip portion of the snare loop according to the second embodiment. 5A to 5C are diagrams for explaining the suturing operation of the biological suturing device according to the first embodiment of the present invention. 5A to 5C are views for explaining a release operation of the biological suturing device according to the first embodiment of the present invention. 4A to 4C are diagrams for explaining the operation of the suture engaging portion of the snare loop and the suture of the biological suturing device according to the first embodiment of the present invention. 1A and 1B are diagrams for explaining the configuration and operation of a biological suturing device according to the prior art. FIG. 10 is a diagram illustrating a suture engagement portion of a snare loop according to the prior art.

Hereinafter, a biological suturing device according to an embodiment of the present invention will be described in detail.
[Basic configuration of the biological suturing device]
As shown in FIG. 1(b), the biological suturing device of this embodiment comprises a suture insertion puncture needle 1 having an internal passage passing axially through it for feeding a suture 50 into the body, a suture withdrawal puncture needle 2 having an internal passage passing axially through it for withdrawing the tip of the suture 50 from the body and arranged in parallel to the suture insertion puncture needle 1, a plate-like connecting member 3 for arranging the suture insertion puncture needle 1 and the suture withdrawal puncture needle 2 side by side, and an operating section 40 including a snare loop 10 having a long, linear tip formed into a loop shape and a cylindrical operating rod 20 which can be inserted and removed through the internal passage of the suture withdrawal puncture needle 2 and which can insert and remove the snare loop 10 from the outside.

As shown in Figure 1(a), the operating unit 40 comprises a snare loop 10, which is a long stainless steel wire with a looped tip, a cylindrical operating rod 20 through which the snare loop 10 passes, and a grip 30 attached to the rear end of the operating rod 20 for the operator to grip with their hand. When viewed axially of the operating rod 20, the snare loop 10 has a suture engagement portion 14 at its tip, which is a twisted U-shaped protrusion.

[Snare Loop of First Embodiment]
As shown in the perspective view of Figure 2(a) and the side view of Figure 2(b), the snare loop 10 protruding from the operating portion 40 is shaped so that when viewed from an oblique angle, it extends laterally (in a direction substantially parallel to the stomach wall and abdominal wall and substantially perpendicular to the downward vertical direction) from the tip of the operating rod 20, and is provided with a suture engaging portion 14 that protrudes in a direction twisted by 90 degrees from the tip and forms a circular portion whose intersecting portions intersect without contacting each other.

That is, as shown in Figure 3, the snare loop 10 of the biological suturing device according to the first embodiment of the present invention has a large loop-shaped tip extending in the XY plane (snare loop plane direction), which is approximately perpendicular to the downward vertical direction, and a U-shaped protrusion having an inner diameter approximately 1.5 to 5 times the outer diameter of the suture 50, twisted 90 degrees (semi-twisted) in the direction of rotation about the Y axis so that the intersecting portions do not contact each other, thereby forming an annular suture engagement portion 14 that extends in the Z direction perpendicular to the XY plane and whose intersecting portions (with a gap) do not contact each other. The twist angle of the suture engagement portion 14 may be close to 90 degrees, may be in the range of 80 to 100 degrees, or may be in an even wider range.

The snare loop 10 according to this embodiment is a solid wire made of austenitic stainless steel (SUS304WP-8) containing, for example, 18.00 to 20.00 chromium (Cr), 8.00 to 10.50 nickel (Ni), and 0.080 or less carbon (C), with an elastic modulus (modulus of elasticity) of approximately 74 GPa and a tensile strength of approximately 1700 to 2500 N/mm2, and has a diameter (referred to as the first diameter in this application) of, for example, 0.16±0.005 mm.

This snare loop 10 can be formed by wrapping and twisting a linear stainless steel cylinder of a specified diameter at any position to define the inner diameter, forming a twisted shape (annular portion) at a specified angle, and then forming it into a loop to capture the suture 50. This allows the protruding U-shape to be twisted in a direction rotating around the Y-axis (the direction twisting the plane of the snare loop).

The suture 50 in this embodiment is made of nylon, a type of polyamide resin formed from a thermoplastic polymeric material whose main chain is composed of repeated amide bonds, and has a diameter of, for example, 0.35 mm. Therefore, compared to the snare loop 10, which is made of stainless steel wire with a diameter of 0.16 mm, approximately half the diameter of the snare loop, the suture 50 is designed so that the force that attempts to maintain its straight shape when hanging vertically downward (referred to as the "straight shape maintaining force" in this invention) is greater due to the difference in material diameter and rigidity. The inner diameter of the annular portion of the suture engagement portion 14 is preferably sufficiently larger, approximately 1.5 to 5 times the outer diameter of the suture 50 (0.35 mm diameter), and is approximately 3 times larger, or approximately 1 mm, in the drawings.

[Suture operation]
The biological suturing device according to this embodiment configured as described above sutures the stomach wall and abdominal wall by carrying out the following surgical steps shown in FIG.

(A) The doctor inserts the suture insertion needle 1 and the suture withdrawal needle 2, which are connected to the abdominal wall 101 and the stomach wall 102 by connecting member 3, into the abdomen from outside the body, so that the tips of the suture insertion needle 1 and the suture withdrawal needle 2 are lined up and open into the stomach. He then inserts the suture 50 through the entrance nozzle 4 to the rear end of the suture insertion needle 1, and inserts the snare loop 10 into the suture withdrawal needle 2 through the entrance nozzle 5, so that the loop portion of the snare loop 10 (the portion that takes in the suture) is extended in a direction approximately parallel to the stomach wall and abdominal wall (horizontal direction) and toward the suture insertion needle 1. Next, as shown in Figure 6(a), the doctor further inserts the suture 50 vertically downward from the suture insertion puncture needle 1, thereby passing the suture 50 through the loop portion of the snare loop 10 extending laterally from the suture withdrawal puncture needle 2 in the direction of arrow (I).

(B) Next, as shown in Figure 6(b), the doctor pulls out the knob 30 of the operating part 40 inserted into the suture withdrawal puncture needle 2 in the direction of arrow B, thereby gradually pulling out the annular part of the snare loop 10, which is the suture 50 extending from the suture insertion puncture needle 1, toward the outlet of the operating rod 20.
(C) A third step in which the doctor further pulls out the suture 50 from the second step, as shown in Figure 6(c), so that the suture 50 fits into and engages with the semi-twisted, annular suture engagement portion 14 provided at the tip of the snare loop 10.

The third step of retaining and engaging the suture thread engaging portion 14 at the tip of the snare loop 10 will be described in detail with reference to FIG. 8, which shows an enlarged view of the vicinity of the suture thread engaging portion 14.
In the third step of holding and engaging the suture 50 with the suture engaging portion 14, as shown in Figure 8(a), as the surgeon pulls out the snare loop 10 in the direction of the arrow T, the snare loop 10 moves in the direction of the arrow H, and the intersection of the twisted portion of the snare loop 10 causes the suture 50 to hit the circular edge of the operating rod 20 of the operating portion 40, and by further pulling the snare loop 10, the suture 50 is pushed (fitted) into the gap in the suture engaging portion 14. As the suture engaging portion 14 continues to be fitted into the gap, in the biological suturing device of this embodiment, the suture 50 has a greater ability to maintain its straight shape due to differences in diameter, hardness, and rigidity compared to the snare loop 10, so the snare loop 10 side within the operating rod 20 undergoes rotational deformation, and the suture 50 behaves as if it is being fitted into the circular portion of the half-twisted suture engaging portion 14 of the snare loop 10, as shown in Figure 8(b).

As shown in Figure 8(b), the biological suturing device of this embodiment holds the suture 50 by fitting it into the circular portion of the semi-twisted suture engagement portion 14 of the snare loop 10. Because the inner diameter of the suture engagement portion 14 is sufficiently larger than the diameter of the suture (approximately 1.5 to 5 times, approximately 3 times in the drawing), the suture 50 is loosely held within the suture engagement portion 14 and can move within it.

(D) Furthermore, in this third step, the doctor can pull out the snare loop 10, which has loosely held and engaged the suture 50 in the suture engagement portion 14, from the suture withdrawal needle 2, pull out the suture insertion needle 1 and the suture withdrawal needle 2 to the outside of the body, and then tie the suture together, thereby suturing the abdominal wall 101 and the stomach wall 102.

[Release action]
Generally, in biological suturing procedures, there are cases where it becomes necessary to release (release) the suture 50 after it has been held and engaged by the suture engaging portion 14. This suture release operation will be described with reference to FIG. 7.

This release operation is performed by the surgeon forcefully pushing the snare loop 10 from the operating rod 20 in the direction of arrow D, as shown in Figure 7(d), from a state in which the suture 50 is retained and engaged with the annular suture engagement portion 14 of the snare loop 10 as shown in Figure 6(c).

In the biological suturing device of this embodiment, as shown in Figure 7(d), by strongly pushing out the snare loop 10, the suture engagement portion 14 of the snare loop 10 is pushed toward the arrow E so that it passes over the position of the suture 50, forcing the suture 50 into the intersection of the annular suture engagement portion 14. Further pushing out the snare loop 10 results in the following: (1) the suture 50 maintains its straight state by its linear shape-maintaining force, dangling downward (the suture 50 is more rigid than the snare loop 10); (2) the suture 50 is loosely held within the diameter of the snare loop 10; and (3) there is a gap in the twisted portion at the intersection of the semi-twisted suture engagement portion 14, causing the suture 50 to be pushed into the intersection from its retained engagement with the annular suture engagement portion 14 of the snare loop 10 and released. If the snare loop 10 cannot be released by pushing it out once, repeating the pushing and pulling operation will cause the suture 50, which has a strong ability to maintain its straight shape, to come into strong contact with the twisted part of the suture engagement portion 14, thereby facilitating release.

In other words, in prior art, the suture engaging portion tightly grips the suture in a U-shape, making it difficult to release the suture from the suture engaging portion. However, in the biological suturing device of this embodiment, the suture engaging portion gently holds the suture without pinching it, utilizes the straight shape-maintaining force (rigidity) of the suture 50, and semi-twists the suture engaging portion 14 to create a gap, allowing for easy release by pushing the snare loop 10 out of the operating rod 20. In other words, in the biological suturing device of this embodiment, the suture 50 has higher rigidity than the snare loop 10, and when the suture engaging portion 14 is inserted into the annular portion of the suture engaging portion 14 and is pushed out of the operating rod 2, it abuts against and enters the gap in the annular portion, and then the suture engaging portion 14 is rotated to disengage from the annular portion 14, allowing for easy release.

[Snare Loop of Second Embodiment]
In the above-described embodiment, an example was described in which a vertical suture engagement portion was provided in which the U-shaped portion was half-twisted, but the configuration of the suture engagement portion according to the present invention is not limited to this. A suture engagement portion may be employed in which the U-shaped portion is twisted nearly 180 degrees to the extent that the intersecting portions do not come into contact in the planar direction of the snare loop. A second embodiment of a biological suturing device employing a snare loop 10 twisted nearly 180 degrees will be described with reference to FIGS. 4 and 5.

As shown in the perspective view of Figure 4(a) and the side view of Figure 4(b), the snare loop 10 of this second embodiment is formed so that when viewed from a perspective, it extends laterally (in a direction approximately perpendicular to the downward vertical direction) from the tip of the operating rod 20. It has a suture engagement portion 141 at the tip that extends laterally (in a direction approximately perpendicular to the downward vertical direction) and is formed by twisting the protruding U-shaped portion, which opens wider than the diameter of the suture, to nearly 180 degrees (approximately full twist) within a range where the intersecting portions do not come into contact with each other.

That is, as shown in Figure 5, which shows an enlarged perspective view of the tip, the snare loop 10 of the biological suturing device according to this second embodiment is configured to have a ring-shaped suture engagement portion 141 at the tip of a large loop portion extending in the horizontal XY plane. The U-shaped protrusion has an inner width (inner diameter) approximately 1.5 to 3 times the outer diameter of the suture 50 and is twisted nearly 180 degrees (less than 180 degrees) so that the intersections do not touch. The intersecting region (intersection portion) E of the twisted stainless steel wire of this suture engagement portion 141 is twisted nearly 180 degrees (less than 180 degrees), so that the intersections of the twisted stainless steel wires are spaced apart without touching. Furthermore, the materials, diameters, elastic moduli, and other characteristics of the snare loop 10 and suture 50 according to this embodiment are the same as those of the first embodiment. In this embodiment, the twist angle of the suture engaging portion 14 may be close to 180 degrees so that the intersections do not come into contact, and may be in the range of 170 degrees to less than 180 degrees, or in a wider range less than 180 degrees, for example.

[Operation of the second embodiment]
The biological suturing device according to the second embodiment configured as described above can perform the suturing operation and the release operation in the same manner as the first embodiment. For example, the suturing procedure involves the steps of: a) pulling the snare loop 10 in, causing the circular edge of the rod 20 of the operating unit 40 to abut against the suture 50; b) pulling out the snare loop 10, causing the circular edge of the rod 20 to push the suture 50 and force the suture 50 into (fit) the minute gap in the suture engagement portion 141; c) the circular edge of the rod 20 further pushing the suture 50, causing the straight shape of the suture 50 to maintain its shape, thereby deforming (rotating) the snare loop 10 and fitting the suture 50 into the minute gap in the suture engagement portion 141; and d) pulling out the snare loop 10, which holds and engages the suture 50 with the suture engagement portion 141, and drawing the suture 50 out of the body; and tying the suture together, thereby suturing the abdominal wall 101 and the stomach wall 102.

The suture 50 is released by the surgeon by forcefully pushing the snare loop 10 off the operating rod 20, bringing the annular suture engagement portion 141 into contact with the suture 50, and then further pushing the snare loop 10. The relatively rigid suture 50 is maintained in a straight state by the linear shape retention force F, causing it to hang downward. Because the suture 50 is loosely held within the inner diameter of the suture engagement portion 14, which is twisted less than 180 degrees, the suture engagement portion 141 of the snare loop 10 moves from a state in which it is loosely holding the suture 50 to a state in which it is pushed into the small gap in the suture engagement portion 141, causing it to release. If the snare loop 10 cannot be released by pushing it out once, repeated pushing and retracting can facilitate release.

In addition, the biological suturing device of this embodiment has a much smaller gap at the twisted intersection of the suture engaging portion 141 than the first embodiment, making it relatively difficult to release compared to the suture engaging portion 14 of the first embodiment. However, conversely, during suturing, the suture 50 does not easily slip into the small gap from the suture engaging portion 141 and become detached, making it easier to pull out the snare loop 10 from the suture withdrawal puncture needle 2.

Other Embodiments
In the above-described embodiments, a first embodiment is provided in which a suture engaging portion 14 is provided that is half twisted (twisted by 90 degrees), and a second embodiment is provided in which a suture engaging portion 141 is provided that is twisted to nearly 180 degrees. However, the suture engaging portion of the biological suturing device according to the present invention is not limited to the structure of the above-described embodiments. Taking into consideration the material and diameter of the suture and snare loop used in the procedure, and the balance between the ease of inserting and releasing the suture into the suture engaging portion and the physician's preference for operability, the twist angle may be set within a range where the intersecting portions do not come into contact, for example, between 30 degrees and 180 degrees.

1 Puncture needle for inserting suture thread, 2 Puncture needle for withdrawing suture thread, 3 Connecting member,
4 entrance cap, 5 entrance cap, 10 snare loop,
14 suture thread engaging portion, 15 suture thread engaging portion, 20 operating rod, 30 picking portion,
40 Operation part, 50 Suture, 101 Abdominal wall, 102 Stomach wall, 141 Suture engagement part

Claims (6)

a suture insertion needle having an internal passage passing therethrough in the axial direction for feeding a suture into a body; a suture withdrawal needle arranged in parallel to the suture insertion needle, and having an internal passage passing therethrough in the axial direction for withdrawing the tip of the suture from the body, and through which the operation rod can be inserted and removed; and a connecting member for arranging the suture insertion needle and the suture withdrawal needle side by side,
the snare loop extends in a loop shape from the tip of the operating rod in a direction substantially perpendicular to the vertically downward direction when protruding from the cylindrical operating rod, and has an annular suture engaging portion in which the tip of the loop shape is twisted at an angle of 30 degrees to less than 180 degrees within a range in which the intersecting portions do not come into contact with each other;
The suture thread has a higher rigidity than the snare loop, and when the snare loop is pushed out from the operating rod while inserted into the suture thread engagement portion of the snare loop, the suture thread is pushed into the intersection portion and disengaged from the suture thread engagement portion of the snare loop. the suture insertion needle has an internal passage passing therethrough in the axial direction for feeding the suture into the body; the suture withdrawal needle has an internal passage passing therethrough in the axial direction for withdrawing the tip of the suture from the body, and the operating rod is insertable and detachable therethrough, and the suture insertion needle is disposed in parallel to the suture insertion needle; and a connecting member for arranging the suture insertion needle and the suture withdrawal needle side by side,
the snare loop is made of a stainless steel solid wire set to a predetermined first diameter;
a biological suturing device formed so as to extend in a loop shape from a tip of the operating rod in a direction substantially perpendicular to a vertically downward direction when protruding from the cylindrical operating rod,
the suture is a long, resin-made single wire, and has a straight shape maintaining force that tends to maintain the straight shape when hanging down in an elongated shape in the vertically downward direction, and the straight shape maintaining force is set by a difference in diameter between the suture and the first diameter of the snare loop being 1.5 to 5 times larger,
The snare loop protrudes from the tip of the loop shape and has an inner diameter set to a range of 1.5 to 5 times the diameter of the suture thread, and has a circular suture thread engagement portion formed by twisting at an angle of 30 degrees to less than 180 degrees so that the intersections do not come into contact. A biological suturing device according to claim 1 or 2, wherein the snare loop has a circular suture engagement portion formed by twisting at an angle of 80 to 100 degrees. A biological suturing device according to claim 1 or 2, wherein the snare loop has a circular suture engagement portion formed by twisting at an angle of 170 degrees to less than 180 degrees. The biological suturing device according to claim 3, wherein the inner diameter of the suture engagement portion of the snare loop is set to a range of two to three times the diameter of the suture. 5. The biological suturing device according to claim 4, wherein the inner diameter of the suture engaging portion of the snare loop is set to be two to three times the diameter of the suture.