JPH0473057A - Bone frame forming device for tubular organ - Google Patents

Abstract

PURPOSE:To eliminate deformation and deviation after implantation into an organism by arranging one pair each of connecting branches so that at least one of two straight lines connecting points at which they are connected to respective rings runs through an axis center while the two straight lines are perpendicular to each other. CONSTITUTION:A holding body 1 is a tubular construction in which numerous rings 21 arranged on the same axis A are coupled together with a pair of connecting branches shorter with a diameter thereof being less than that of the rings 21. Straight lines L1 and L2 connecting two points at which the rings 21 are connected to one pair each of the connecting branches 31 and 31' and 32 and 32' are perpendicular to each other while at least one of the L1 and L2 runs through the center axis A. According to a position at which the L1 and L2 are perpendicular to each other on the center axis A, for example, if the L1 is a straight line which does not run through the center axis A, as the L1 separates further from the center axis A further, bending is worsened in such a direction while it is better in an opposite direction thereto. An angle of the bending may be determined properly depending on the type of an artificial organ and an object to be transplanted.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a tool for forming the skeleton of a tubular organ. More specifically, the present invention relates to a plastic molding that forms a tubular skeleton of an artificial organ when repairing tubular organs such as the trachea and bronchi.

<Prior art> Artificial blood vessels, artificial tracheas, artificial esophagus, and other tubular artificial organs have been actively developed in recent years as substitutes for tubular organs such as blood vessels, tracheas, and esophagus, and are being used in clinical applications for various diseases. There are also many reports on these topics. In general, the conditions required for tubular artificial organs are: ■ have high fatigue strength and durability, and do not deteriorate in the body; ■ have low inflammation and integrate with surrounding tissues; ■ have appropriate porosity. It must have appropriate strength, lumen retention, elasticity, and extensibility; ■ It must not degenerate due to disinfection or sterilization; ■ It must survive in living organisms; ■ It must not fall off or deform due to suture failure, etc. .

In conventional artificial tubular organs, in order to satisfy the above conditions, materials have to be selected, weaving methods have been devised, and bellows have been applied (Japanese Utility Model Publication No. 51-50394).
Fixing coagulation factor X on the wall of a tubular body
7-115250), various ideas have been made.

Among these tubular artificial organs, skeletal organs (such as the trachea and bronchi)
An artificial organ (hereinafter referred to as an artificial trachea) that substitutes for a tubular organ having cartilage (cartilage) was developed in 1950 by
A report on a clinical case using stainless steel wire covered with fascia by Daniel et al.
Since the experimental report using a glass tube by Daniel R.A., many researchers have investigated using various materials, but the common requirements for an artificial trachea are: It has support properties, does not allow air to leak, has little inflammatory reaction, and is well absorbed into the body. In order to meet these conditions, methods using meshes and methods using tubes without holes have been studied in the past, but in recent years, the use of a skeleton-forming part (hereinafter referred to as a holder) has been studied.
Structures in which the material is covered with mesh such as woven or knitted fabrics have been proposed and are being studied. Mr. Fubile of the United States (N
eville) is the ideal condition for an artificial trachea.■
Airtight (exhalation and intake air does not escape); Appropriate strength
Luminal retention ability (trachea does not collapse) ■ Adheres to the body, ■ Integrates with surrounding tissue with little inflammation, ■ Does not allow fibroblasts to pass through and does not allow bacterial invasion, ■ Epithelium fits into the airway lumen. However, there are six conditions for conventional artificial tracheas, including those with a structure in which the holder is covered with mesoche, that satisfy all of the conditions (1), (2), and (3). do not have. Regarding the artificial trachea with its holder,
Conventionally, devices as shown in FIGS. 4 and 5 have been proposed. The one in Figure 4 is what is called an old type of arch-shaped graft, and is a tunnel-shaped mesh reinforced with a half-ring-shaped holder, and the one in Figure 5 is the same as the one in Figure 4, but is attached to the floor of the tunnel. The corresponding parts have been omitted. All of them have a problem with the condition (2) above (due to poor lateral flexibility, peeling and deviation occur, making engraftment impossible).

<Problems to be Solved by the Invention> The present invention has been made in view of the above circumstances, and an object thereof is to provide a holder for a tubular artificial organ that does not cause deformation or deviation after being transplanted into a living body.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides a method in which adjacent rings of a large number of plastic rings arranged on the same axis,
A tubular structure connected by a pair of connecting branches each having a radius shorter than the radius of the ring, with respect to two pairs of connecting branches adjacent in the axial direction on any ring except for both ends,
A configuration characterized in that at least one of the two straight lines formed by connecting the points where each pair of connecting branches connects with its ring passes through the axis, and the two straight lines are orthogonal to each other. is adopted.

<Function> Since the holder of the present invention is constructed as described above, it can be bent in any direction, front, rear, left, right, etc. By appropriately selecting the position of the connecting branch, the bending angle in the front/rear direction can be changed, for example. It is also possible to provide a difference.

Furthermore, the presence of the connecting branch restricts excessive extension in the axial direction, and also makes it difficult for the ring to slip, improving the lumen retention force.

Furthermore, since the movement of the sewing thread is restricted at the connecting branches, the fabric placed over the holder will not shift.

<Example> Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a perspective view of the holder of the present invention, and FIG. 2 is a perspective view of the holder of the present invention.
FIG. 3 is a diagram showing an artificial trachea in which the holder shown in the figure is covered with a polyester knitted mesh, and FIG. 3 is a diagram for explaining the positional relationship of a pair of axially adjacent connecting branches for an arbitrary ring.

As shown in FIG. 1, the holder (1) of the present invention has a large number of rings (2) arranged on the same axis (A).
It is a tubular structure connected one after another by a pair of connecting branches (3) shorter than the radius of (2), and the connecting branches (3) are preferably arranged oppositely. In other words, two sets of connecting branches (3) adjacent in the axial direction on any ring (2) excluding both ends
), each pair of connecting branches (3) is connected to its ring (
The two straight lines formed by connecting the points that connect with 2) are the central axis (
A) They are arranged orthogonally on the top.

The ring (2) constitutes the side wall of the holding body (1),
Synthetic resins that are generally compatible with living organisms, such as olefin resins such as polyethylene and polypropylene, fluororesins such as polytetrafluoroethylene and ethylene tetrafluoroethylene copolymers, and polyesters are preferably used, but are not particularly limited. It is formed flat in the direction, that is, the direction of the central axis (A) of the holder (1), and maintains an appropriate compressive strength so that the holder (1) does not collapse after implantation.

The compressive strength of the artificial trachea is generally, but not limited to, 500 g in the direction perpendicular to the longitudinal axis of a 5 cm long artificial trachea.
When a load of 1 is applied, the compression rate is approximately 5 to 25%, and the thickness of the ring (2), which determines the compressive strength, varies depending on the forming material used.

The connecting branch (3) connects the ring (2) and is integrally formed of the same material as the ring (2). Connecting branch (3)
The length of the ring is shorter than the radius of the ring (2), and its thickness is not limited, but it is preferably made equal to the thickness of the ring (2) in consideration of strength and ease of molding. As shown in FIG. '; 32. A straight line connecting the two points where 32) and ring (21) connect, ,
L are orthogonal to each other, and at least one of L and L passes through the central axis (A). Preferably, both the straight line and the straight line Lx pass through the central axis (A) (opposite arrangement in plants). The distance between the straight line (L) that does not pass through the central axis (A) and the central axis (A) varies depending on how the bending angle of the holder (1) is determined with respect to the axis (A). For example, if Ll is a straight line that does not pass through the central axis (A) from a position that is perpendicular to the central axis (A), the farther Ll is from the central axis (A), the more it bends in that direction. is worse and bending in the opposite direction is better.

The bending angle may be appropriately determined depending on the type of artificial organ and the transplant target.

When used, for example, a knitted fabric of polyester fiber (K:
A mesh (M) is sewn onto the holder (1) using a thin thread (not shown) made of the same material to create an artificial organ.

Example 1] Holding body of the present invention (diameter 20 cm, width 3 m, thickness 0.5 m,
When we conducted a transplantation test on dogs using an artificial trachea made of polytetrafluoroethylene (polytetrafluoroethylene) covered with a polyester knitted mesh from the inside and sewn with polyester suture thread, we obtained the results shown in Table 1. . No cases of death caused by the carrier were observed. However, dogs weigh between 10 and 15 kg.
28 g adults (m) were used.

[Comparative Example 1].

A transplantation test similar to that in Example 1 was conducted using an artificial trachea in which a polyethylene holder as shown in FIG. 4 was covered with a polyester knitted mesh, and the results shown in Table 1 were obtained. Holder deformation has occurred. However, dogs weigh 10
Twenty adult (male) animals weighing ~14 kg were used.

[Comparative Example 2] A transplantation test similar to that in Example 1 was conducted using an artificial trachea in which a polyethylene holder as shown in Figure 5 was covered with a polyester knitted mesh, and the results shown in Table 1 were obtained. It was done. Similar to Comparative Example 1, deformation of the holder occurred. however,
Five adult (male) dogs weighing 7 to 13 kg were used.

[Comparative Example 3] A transplantation test similar to that in Example 1 was conducted using an artificial trachea made of a silicone tube (manufactured by N Company, USA) as shown in Figure 6, and the results shown in Table 1 were obtained. . Tracheal prolapse occurs. However, dogs must be adults weighing 9 to 13 kg (
a) 10 animals were used.

Hereinafter omitted <Effects of the Invention> By using the holder of the present invention, the following effects can be achieved.

(1) Since the holder has appropriate elasticity and deformability, there is little discomfort after transplantation.

(2) Since the lumen retention force is good and there is no excessive extension, deformation or deviation of the holder does not occur, and therefore long-term survival of the living body after transplantation is possible.

(3) Since the movement of the sewing thread is small, the mesh does not slip easily.
Therefore, granulation cells can easily invade and spread into the mesh after transplantation, and endothelial cells can easily attach thereto.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the holder of the present invention, and FIG. 2 is a perspective view of the holder of the present invention.
FIG. 3 is a diagram showing an artificial trachea in which the holder shown in the figure is covered with a polyester knitted mesh, and FIG. 3 is a diagram for explaining the positional relationship of a pair of axially adjacent connecting branches for an arbitrary ring. Moreover, FIGS. 4 to 6 are diagrams showing examples of conventional holders. <Explanation of main symbols> 1: Holding body 2 Eli, Gu: Connecting technique M: Mesoshu

Claims (1)

[Claims] 1) A tubular structure in which a number of adjacent plastic rings arranged on the same axis are connected by a pair of connecting branches each having a radius shorter than the radius of the ring. ,
For two sets of connecting branches adjacent in the axial direction on any ring other than both ends, at least one of the two straight lines formed by connecting the points where each pair of connecting branches connects with its ring passes through the axis. , and the two straight lines are arranged so as to be orthogonal to each other. A tool for forming a skeleton of a tubular organ. 2) The tool for forming a skeleton of a tubular organ according to claim 1, wherein the connecting branches are arranged oppositely.