JP2019111298A - Surgical suture - Google Patents

Abstract

To provide a surgical suture that facilitates suture, has excellent knotting performance, and achieves a braid structure whose knotted part is small.SOLUTION: A surgical suture having a braid structure includes a core yarn at a central part thereof and a sheath yarn around the core yarn. The sheath yarn is a multifilament yarn having a single fiber fineness of 1 dtex or less and a total fineness of 15-150 dtex. The core yarn has a knot tensile strength of 1 N or more, and a braiding angle of more than 5° and not more than 30°. Flatness of the surgical suture is 20-40%.SELECTED DRAWING: None

Description

  The present invention relates to a surgical suture, and more particularly, to a surgical suture having a braid structure that is easy to suture, ligature, and has a small ligature.

Surgical sutures are used to attract and fix dislocated tissues such as skin wound sites and surgical sites in the body. As the performance required for the suture, in addition to the mechanical strength that can withstand the stress at the time of ligature (tie the suture), it is required that it is easy to suture, easy to ligate, and further that the ligature portion is small.
Here, the easiness of suturing means that the resistance of the suture when passing through the living tissue is small. The resistance when the suture passes through the living tissue etc. leads to the damage of the living tissue, which will delay the healing.
In addition, here, ligability easily means that tissue is not drawn at the time of ligature and that a knot (ligature) is not loosened. For example, in the case of using a suture having a large strain to the ligature stress, it is easy to apply an excessive force, and as a result, the tissue is pulled and the state after healing is impaired. If not added, the knot will loosen and the affected tissue will break up again. On the other hand, since the appropriate ligature is different depending on the shape (monofilament, multifilament, braid structure) and size of the suture, depending on the type of suture, tissue will not be drawn at the time of ligation and the knot will not loosen. It takes a lot of experience and high skills to be able to adjust the coordination skills.
Furthermore, surgical sutures are required to be small in size from the viewpoint of preventing foreign body reaction and inflammatory reaction.

With respect to the required performance of such surgical sutures, Patent Document 1 below discloses a suture having a core at the center of the suture and a braid structure made of polyester fiber at the sheath. ing. In Patent Document 1, by arranging a core thread at the central portion, mechanical strength necessary at the time of suturing is improved, and by setting a set angle high, elasticity is given to the suture at the time of ligation, and the knot does not loosen. It has a suture design. However, as described above, when using a suture having a large strain, that is, a high stretchability, an excessive force is applied to cause the tissue to be pulled, but Patent Document 1 mentions the solution of the problem. Not. The suture described in Patent Document 1 has a high assembly angle, and is a structure that easily causes friction with tissue when the suture passes through a living tissue. Furthermore, Patent Document 1 does not mention at all about reducing the size of the ligature.
As mentioned above, a suture satisfying all the required performances has not been obtained so far.

JP, 2015-42195, A

  In view of the above background art, the problem to be solved by the present invention is to provide a surgical suture suitable for fixing a skin wound site or an internal tissue, which is easy to suture, easy to ligate, and has a small ligature. It is.

  The inventors of the present invention have intensively studied to solve the above problems, and as a result of repeating experiments, it is possible to solve all these problems by having a core yarn in the center and assembling the periphery with ultrafine fibers. The present invention has been completed.

That is, the present invention is as follows.
[1] A surgical suture of braided construction comprising a core yarn in the center and a sheath yarn around it, wherein the sheath yarn is a multifilament yarn having a single yarn fineness of 1 dtex or less and a total fineness of 15 dtex to 150 dtex or less A surgical suture characterized in that a knot tension of the core yarn is 1 N or more, a set angle is more than 5 ° and 30 ° or less, and a flatness of the suture is 20 to 40%.
[2] The surgical suture according to the above [1], which has an elastic modulus of 30 cN / dtex or more and a knot tension of 5 N or more.
[3] The surgical suture according to [1] or [2], wherein the core yarn is a multifilament yarn having a single yarn fineness of 1 dtex or less and a total fineness of 30 dtex to 150 dtex.

  The surgical suture according to the present invention is easy to sew, ligatures, and has a small ligature portion, so it can be suitably used as a 4-0 size to 2 size surgical suture according to USP standard.

It is an explanatory view for computing the flat rate of a suture.

Hereinafter, embodiments of the present invention will be described in detail.
The surgical suture of the present embodiment is a suture having a braided structure including a core at the center and a sheath around it, and the sheath has a single yarn fineness of 1 dtex or less and a total fineness of 15 dtex to 150 dtex. The following multifilament yarns, characterized in that the knot tension of the core yarn is 1 N or more, the assembly angle is more than 5 ° and 30 ° or less, and the flatness of the suture is 20 to 40%. I assume.
The single yarn fineness of the sheath yarn constituting the braided suture according to the present embodiment is required to be 1 dtex or less. When the single yarn fineness exceeds 1 dtex, the flexibility in the compression direction is impaired, and it becomes difficult to control the flatness to be described later to 20 to 40%. In addition, when the value of the single filament fineness exceeds 1 dtex, the ligature becomes large and the risk of the inflammatory reaction becomes high. The single yarn fineness of the sheath yarn constituting the braided suture according to the present embodiment is preferably 0.7 dtex or less, more preferably 0.5 dtex or less. The lower limit of the single yarn fineness is 0.01 dtex from the viewpoint of feasibility. As a standard of the size of a ligature part, 1.5 mm or less is preferable, More preferably, it is 1.2 mm or less.

  The total fineness of the sheath yarn constituting the braided suture according to this embodiment is required to be 15 dtex to 150 dtex or less. If the total fineness is smaller than 15 dtex, the strength is insufficient and it can not withstand the nodal tensile strength according to the USP standard and it breaks. The suture size that is preferably used for fixing the wound site of the skin or body tissue is usually USP4-0 to USP2, but if the total fineness exceeds 150 dtex, the diameter of the braided suture exceeds the USP 2 standard, and surgery Not suitable for use with sutures.

  The number of filaments of the multifilament yarn which is a sheath yarn may be an appropriate value according to the standard of the suture, but is preferably 8 to 500, more preferably 24 to 380.

  The assembly angle of the surgical suture of the braid structure of this embodiment is required to be more than 5 ° and not more than 30 °. When the pair angle is larger than 30 °, elasticity appears and causes drawing of tissue. On the other hand, if the set angle is 5 ° or less, the stability of the form of the braid is degraded and the convergence of the ultrafine yarn is degraded. The preferred range of braid assembly angle is more than 5 ° to 20 °, more preferably 8 ° or more and 15 ° or less.

  The flatness of the surgical suture of the braided structure of the present embodiment is required to be 20 to 40%. Here, as shown in FIG. 1, the flatness is fixed to a jig capable of applying the same stress as the nodal tensile strength determined in accordance with the manufactured USP standard, and the suture is The cross section was observed with a microscope (VHX-5000 manufactured by KEYENCE CORPORATION), and when the major axis is a and the minor axis is b, it is a value calculated by (a−b) / a × 100. For example, when measuring the flatness of a suture according to the USP 4-0 standard, 9.8 N which is a load applied at the time of knotting is added, and the flatness is calculated by the method described above. When the flatness is lower than 20%, the ligature becomes large and the inflammatory response becomes large. The size of the nodule is preferably 2 mm or less, more preferably 1 mm or less. On the other hand, conditions higher than 40% are too flat, poor convergence and cause a reduction in suture strength during operation. The preferred range of flatness of the suture is 25-35%, more preferably 27-32%.

  The modulus of elasticity of the surgical suture of the braid structure according to this embodiment is preferably 30 cN / dtex or more, more preferably 40 cN / dtex or more. By setting the elastic modulus to 30 cN / dtex or more, the knot can be securely fixed without stretching the suture at the time of knotting.

  The knot tensile strength (knot strength) of the surgical suture of the braid structure of the present embodiment is preferably 5 N or more. If the knot strength is less than 5N, it will not withstand the stress at the time of suture and it will break. The knot tensile strength (knot strength) of the surgical suture of the braid structure of the present embodiment is more preferably 8 N or more, and still more preferably 10 N or more.

  The material of the sheath yarn of the surgical suture of the braid structure according to the present embodiment is selected from the group consisting of polyamide, polyester, polyolefin, and aliphatic polyester such as polylactic acid and polyglycol from the viewpoint of excellent biosafety. Preferably, it is at least one. Furthermore, polyester is more preferable from the viewpoint of affinity with living tissue.

  The number of braided threads of the sheath thread of the surgical suture of the braid structure according to the present embodiment is not particularly limited, but the number of sheathed threads is preferably 8 to 64, and more preferably There are eight to twenty-four. If the number of sheath yarns is less than eight, it is necessary to increase the total fineness to produce a thickness conforming to the standard of the suture, and the flatness becomes smaller. On the other hand, in the case of 64 or more, the suture becomes thick.

  The surgical suture of the braided structure of the present embodiment has a core yarn. The knot tension of the core yarn needs to be 1 N or more. If the strength of the core yarn is lower than 1 N, it can not withstand the stress at the time of ligation and it breaks. There is no upper limit of strength, and an appropriate value may be used depending on the suture site, but it is preferably 1N to 100N, more preferably 1N to 60N. The fineness of the core yarn is preferably in the range of 30 dtex to 150 dtex, more preferably 30 dtex to 100 dtex, and still more preferably 35 dtex to 70 dtex. The single yarn fineness of the core yarn is preferably 1 dtex or less. More preferably, it is 0.5 dtex or less. The lower limit of the single yarn fineness is 0.01 dtex from the viewpoint of feasibility. The core yarn may be monofilament or multifilament, but multifilament is preferred from the viewpoint of fiber flexibility. The number of filaments of the multifilament may be an appropriate value according to the standard of the suture, but is preferably 8-500, more preferably 24-380. The modulus of elasticity of the core yarn is preferably 30 cN / dtex or more, more preferably 40 cN / dtex or more.

  The material of the core yarn is preferably at least one selected from the group consisting of polyamide, polyester, polyolefin, aliphatic polyester such as polylactic acid and polyglycol, and silk, from the viewpoint of excellent in biosafety.

  Hereinafter, the present invention will be specifically described by way of examples and comparative examples, but the present invention is not limited to the following examples. Main measured values of physical properties were calculated by the following method.

(1) Fineness of yarn Obtain a sample 90 rotations using a measuring machine with a frame diameter of 1.125 m and measure the weight. The obtained weight was converted to a weight of 10000 m to calculate the total fineness (dtex). The single yarn fineness was calculated by dividing the calculated total fineness by the number of filaments.

(2) Measurement of elastic modulus of suture thread The elastic modulus of suture thread is an elastic modulus measured by a tensile tester (AGS-500NG manufactured by Shimadzu Corporation), and was calculated from loads at 1% and 2% tensile elongation.

(3) Yarn assembly angle A suture manufactured by a stringing machine is measured with a digital microscope (VHX-5000 manufactured by Keyence Corporation), and a 5-point assembly angle is measured by image analysis using the attached software. The set angle of the suture.

(4) Flatness The manufactured suture was fixed to a jig capable of applying a load of nodal tensile strength according to the USP standard shown in FIG. The observation of the cross section of the suture is performed using a digital microscope (VHX-5000 manufactured by Keyence Corporation), and when the major axis is a and the minor axis is b, the following formula:
Flatness = (a-b) / a x 100
The value calculated by was taken as the flattening.

(5) Knot Size The prepared suture was used to form a male knot used for suturing, and the cross-sectional size was measured. The size of the cross-section referred to here is the length of the flattened suture in the short diameter direction.

(6) Nodular tension (Nodular strength)
The knot tension of the core yarn forms a single knot on the core yarn, which is fixed so that the single knot is placed in the middle between 200 mm wide chucks of a tensile tester (AGS-500NG manufactured by Shimadzu Corporation), and the tensile test is carried out The stress at the time when the half-broken point breaks is taken as the nodal tension. The knot tension of the suture forms a single knot on the prepared suture, and it is fixed so that the single knot is placed between 200 mm wide chucks of a tension tester (AGS-500NG manufactured by Shimadzu Corporation), and the tension test is performed. The stress at the time of breaking at the place where it was carried out and partially tied was taken as nodal tensile strength.

Example 1
In order to produce a suture according to the USP 4-0 standard, 16 bobbins obtained by winding a polyethylene terephthalate yarn having a single yarn fineness of 0.13 dtex and a total fineness of 20 dtex are installed in a sheath yarn, and a single yarn fineness of 0.13 is provided for the core yarn. A polyethylene terephthalate yarn of dtex and total fineness of 46 dtex was placed and braided to produce a braided suture. The elastic modulus, set angle, flatness, and knot size of the obtained sutures are shown in Table 1 below.

[Examples 2 to 6, Comparative Examples 1 to 5]
A braided suture was produced in the same manner as in Example 1 except that the single yarn fineness, the total fineness, the assembly angle, and the number of sheath yarns of the sheath yarn and the core yarn were changed as shown in Table 1 below. Only in Comparative Example 5, a suture was produced using silk. The elastic modulus, set angle, flatness, and knot size of the obtained sutures are shown in Table 1 below. The comparative example 1 has a high set angle, the stretchability of the suture is easily developed, and the elastic modulus decreases to 20%. In Comparative Example 2, since the set angle was low, the convergence of the yarn became worse, fluff was generated, and use as a suture was difficult. Comparative Example 3 had a high single yarn fineness, and a low degree of flatness, so the size of the knot increased to 1.5 mm. In Comparative Example 4, the modulus of elasticity was 25% because there was no core yarn, and the strength was also reduced, making measurement impossible. In Comparative Example 5, the strength was reduced by using a silk thread, and the knot tension of the suture was reduced to 4N.

  When the flatness is less than 20% in Comparative Examples 1 to 6, the nodular portion is large. In addition, when the strength of the core thread is less than 3 N, the knot tension of the suture is reduced and it is not suitable for use.

  The surgical suture according to the present invention is easy to sew, ligatures, and has a small ligature portion, so that it can be suitably used as a 4-0 size to 2 size surgical suture according to USP standard.

a major diameter of suture cross section b minor diameter of suture cross section

Claims (3)

  A surgical suture of braided construction comprising a core yarn in the center and a sheath yarn around it, wherein the sheath yarn is a multifilament yarn having a single yarn fineness of 1 dtex or less and a total fineness of 15 dtex to 150 dtex. A surgical suture characterized in that the knot tension of the yarn is 1 N or more, the set angle is more than 5 ° and 30 ° or less, and the flatness of the suture is 20 to 40%.   The surgical suture according to claim 1, wherein the elastic modulus is 30 cN / dtex or more and the knot tension is 5 N or more.   The surgical suture according to claim 1 or 2, wherein the core yarn is a multifilament yarn having a single yarn fineness of 1 dtex or less and a total fineness of 30 dtex to 150 dtex.

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