Retention Suture Bridge

Abstract

Apparatus for controlling and distributing the tension of retention sutures used in abdominal surgery has a bridging element that may be placed across the surgical incision underneath the loosely tied suture. The surgeon obtains the desired suture tension by placing the tied suture within a slot in a positive locking capstan that is mounted on the bridging element, and rotating the capstan to take up the slack. An increase in the suture tension caused by swelling of the wound may be released by turning the capstan in the reverse direction.

Description

BACKGROUND OF THE INVENTION

Retention sutures (stay sutures) are frequently employed in abdominal and thorasic surgery when the surgeon is concerned with wound dehiscence because of age or condition of the patient. Such sutures are placed through the skin a distance away from the incision, downwardly through the fatty and muscular layers by means of a curved needle, then upwardly through both layers and the skin at the opposite side of the incision, and tied in a knot to draw the edges of the skin together. A preferred surgical technique is to apply the suture in a figure-of-eight configuration in which the lower loop of the suture surrounds the severed portions of muscular tissue and the upper loop is completed by tying a knot above the skin layer. In either case the knotted suture crosses the incision and rests on the sensitive skin adjacent to the wound. As swelling frequently occurs after surgery, it is customary for the comfort of the patient to provide a device to release and distribute the stress applied as the suture tension increases.

Makeshift devices for use with retention sutures have proliferated as surgeons have tried bridges, stents, cushions, sleeves, splints, bolsters, bars, shields, buffers, rolls, pads, buttons, tubing, pants, bumpers, boots, and booties. Perhaps the most widely used devices in the United States are rubber or plastic tubes which are generally available and easy to use because they can be quickly cut to the desired length. Such tubes have the advantage of simplicity, flexibility, and softness, but the tubing itself can cause skin necrosis and there is no way of adjusting the suture tension.

Surgeons have also used bridges, shields, and bars in conjunction with retention sutures. Such devices are placed across the wound and the retention suture is tied over it. A suture bridge has the advantage over a tube of better distribution of pressure over the skin surface and acts as a strut thereby preventing cutting as the suture comes through the skin. One such device that is adaptable to varying breadth of the retention suture line is described in Surgery, Gynecology, and Obstetrics, Volume 124, pages 359-361, Feb. 1967.

The basic design of suture bridges is important as high arched bridges tip or topple; flat bridges press on the incision; wide bridges obscure the wound; narrow bridges invite skin necrosis; hard bridges cut into the skin; and soft bridges buckle. A bridge suitable for one patient may not be suitable for the next or even for the next or even for the next retention suture in the same patient. A major disadvantage of most suture bridges however, similar to the problem encountered with rubber or plastic tubes, is the inability to adjust suture tension. A suture bridge that will support the suture in such manner that it will not bear on the wound while permitting adjustment of the suture tension following surgery is described in U.S. Pat. No. 1,852,098.

In view of the above it will be understood that an object of the present invention is to provide an improved surgical suture bridge. More specifically it is an object of the invention to provide a bridge with adjustable means to either increase or decrease suture tension at any time following placement of the suture by the surgeon.

SUMMARY OF THE INVENTION

The suture bridge of the present invention may be molded of a transparent plastic material in two parts. The bridging element has a plurality of openings spaced longitudinally so that when placed across the incision after suturing, each end of the suture as it exits through the skin will be in approximate registration with an opening and therefore may pass through the bridge and be tied above a longitudinal slot therein, adapted to receive the suture.

The suture when tied in position above the bridge engages a positive locking capstan that is mounted on the bridge for rotation. The tension of the tied suture may be adjusted at any time by rotating the capstan as will be better understood from the following descriptions when read in conjunction with the accompanying drawings wherein:

FIG. 1 shows the suture bridge in place and in locked position;

FIG. 2 is a vertical cross section, thereof and taken along lines 2--2 of FIG. 1;

FIG. 3 is an enlarged fragment in cross section of FIG. 2 showing the locking post in elevation;

FIG. 4 is a plan view thereof;

FIG. 5 is a vertical cross section of FIG. 3 taken along lines 5--5;

FIG. 6 is a perspective of the locking post;

FIG. 7 is a plan view similar to FIG. 4 and of the suture placed in position prior to tightening and locking;

FIG. 8 is a vertical cross section thereof taken along lines 8--8 of FIG. 7;

FIG. 9 shows the surgeon placing the bridge in position after the retention suture has been placed;

FIG. 10 illustrates the appearance of the suture after it is tied, with the retention bridge in place across the surgical incision;

FIG. 11 shows the surgeon engaging the suture in the positive locking capstan; and

FIG. 12 illustrates the manner in which the surgeon can adjust suture tension by rotating the capstan.

Referring first to FIGS. 1-3 which best illustrate the construction of the bridge element 10, it will be noted that it is constructed with a slightly concave lower surface 11 adapted to conform with the abdomen of a patient. The bridge 10 has a thickened central portion 12 and a first cylindrical bore 13 in the upper surface 14 of said thickened portion that is perpendicular to the longitudinal axis of the bridge. A second cylindrical bore 15 in the bridge is concentric with said first bore and of smaller diameter. The thickened portion of the bridge and the first and second bore are transversed by a slot 16 that extends along the upper surface of the bridge parallel to its longitudinal axis. Openings 17 are spaced centrally and longitudinally from each end of the bridge toward the central portion in line with the slot and extend through the bridging element from the upper surface 14 to the lower surface 11.

A positive acting capstan 20 is positioned within the bore 15. The construction of this capstan and its mode of operation will be best understood by referring to FIGS. 4, 5, and 6. The capstan is constructed with a flange 21 at the upper end and has a cylindrical body portion 22 that is received by the bore 15 of the bridging element for slidable and rotary motion thereto. The flange at the upper end of the capstan has cogs 23 spaced around the circumference thereof. Both the capstan and cogged flange are bisected by a slot 24 characterized by a V-shaped entrance.

Stop pins 25 are spaced around the circumference of the bore 13 and engage the cogs 23 when the capstan is pressed downwardly toward the lower surface of the bridge. These pins are disengaged when the capstan is pulled upward.

The capstan may be secured within the bore 15 by a bolt 26.

Further details of the present invention are best understood within the framework of its use by the surgeon. Referring now to FIG. 9, there is shown the hand of a surgeon passing one end of a retention suture through the bridge. The other end of the suture is passed through an opening chosen so that when the bridge is in position across the incision as shown in FIG. 10, the section of the bridge between the suture ends closely approximates the suture spacing, i.e., so that the openings used to receive the suture 30 are in approximate registration with the bridge as best shown in FIG. 10. The suture is tied by the surgeon to complete a loop above the points of emergence of the suture from the skin.

After the suture is properly tied, the surgeon lifts the capstan upwardly in the direction of the arrow in FIG. 8 so that it is free of the stop pins 25 and rotates the cogged flange to align the slot 24 in the capstan with the slot 16 of the bridge. The suture is then laid in the slot 24 as best shown in FIG. 11 and the capstan is rotated clockwise as shown in FIGS. 7 and 8 until the tension of the suture is that desired by the surgeon (see FIG. 12). The capstan is then pressed downward to engage the cogs 23 with the stop pins 25 thus locking the suture in position.

If the wound should swell thereby increasing suture tension, the surgeon may relieve the tension by moving the capstan to its upper position above the stop pins 25, rotating the capstan in a counterclockwise direction to unwind the suture and again depressing the capstan to engage the stop pins 25 when the proper tension is approximated.

It will be noted from FIGS. 1 and 2 that the ends of the bridging element are turned upwardly which prevents the bridge from cutting into the skin of the patient. The bridge may be molded from any thermoplastic material such as methyl methacrylate. The preferred material is a polycarbonate resin such as that manufactured by the General Electric Co. under the trademark Lexan because this material is flexible, has exceptional clarity and will withstand autoclaving.

As best illustrated in FIG. 2, the bridge distributes the stress resulting from the tension of the suture over a relatively large skin area while the appreciable width of the suture and the proximity of the suture to the surface of the patient's body imports lateral stability to the bridge and prevents it from tipping over.

From the foregoing description of the invention it will be readily apparent that an improved surgical bridge is made available to the surgeon that will reduce the incidence of disfiguration by wound scars and contribute to the comfort of the patient undergoing surgery.

Claims

What is claimed is:

1. A surgical apparatus for use in controlling and distributing the tension of transverse retention sutures comprising:

a surgical incision bridging element, having a thickened central portion;

a cylindrical bore in said thickened portion perpendicular to the longitudinal axis of said bridging element, said cylindrical bore being transversed by a slot extending parallel to said longitudinal axis;

openings spaced centrally and longitudinally beyond each side of said slot and extending through the bridging element;

a positive locking capstan characterized by a cogged flange at the outer end, positioned within said bore for slideable and rotary motion relative thereto;

a slot transversing said cogged flange; and,

a stop adjacent the wall of said bore and integral with the bridging element, adapted to engage the cogged flange when slideably moved to its inward position.

2. The surgical apparatus of claim 1 wherein said bridging element is molded of a transparent plastic material.

3. The surgical apparatus of claim 2 wherein said plastic material is stable at elevated temperatures whereby the apparatus may be repeatedly sterilized by autoclaving.

4. The surgical apparatus of claim 1 wherein the bridging element is characterized by a concave lower surface.

5. The surgical apparatus of claim 1 wherein a plurality of stops are positioned around the circumference of said bore.

6. The surgical apparatus of claim 1 characterized by a V-shaped entrance to the slot transversing the cogged flange, whereby the placement of a suture in the slot is facilitated.