Device for connecting body tissues

A device for connecting body tissues has a head part, which can be pushed into a body opening and has a longitudinal axis, wherein tissue staples are accommodated in the head part in a storage position. The tissue staples have a linear main section and two engagement sections projecting perpendicularly therefrom aligned in a first plane perpendicular to the longitudinal axis. Optimal usability in the human body is achieved by rotor elements, which are pivotable about an axis parallel to the main sections of the tissue staples with each have a bearing surface for an engagement section of a tissue staple to rotate said tissue staple from the storage position into a working position in which the tissue staple is arranged in a further plane oriented perpendicularly to the first plane, and in that a slider is provided to advance the tissue staple and deform it into a clamping position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national stage filing based upon International PCT Application No. PCT/AT2017/060264, filed 17 Oct. 2017, which claims the benefit of priority to Austria application No. A 50932/2016, filed 17 Oct. 2016.

BACKGROUND

The present invention relates to a device for connecting body tissues, having a head part with a longitudinal axis which can be pushed into a body orifice, wherein, in the head part, a plurality of tissue staples are accommodated in a storage position, which consist of a linear main section and two engaging sections projecting perpendicularly therefrom and which are each aligned in a first plane which is substantially perpendicular to the longitudinal axis.

It is known in medicine to close wounds with tissue staples, which are inserted into the skin in the area of the wound edges and then deformed in order to fix the wound edges against each other. Devices have been developed to carry out this process, which are generally referred to as staplers. Such devices are described in U.S. Pat. No. 5,170,926 A, EP 1 695 668 A or EP0 354 724 B, for example. Typically, several tissue staples are stacked in a magazine, similar to paper staples. Before use, the foremost tissue staple is turned into a position in which it can be advanced and inserted into the skin.

The present invention relates to devices suitable for connecting sections of body tissue of the type described above, with the difference, however, that the device is sufficiently small and compact to be inserted into artificial or natural body orifices in order to connect body tissue inside the body. It therefore relates to the use in endoscopic or laparoscopic interventions. The particular requirement is therefore to design the device with the smallest possible cross-section, to safely apply the necessary actuating forces and to guarantee a high level of reliability, since direct visual and tactile control is not possible in this form of application.

Various devices for connecting body tissues inside the body have become known. However, these devices are complex to use and often only suitable for special applications.

SUMMARY OF THE INVENTION

It is the object of the present invention to create a simple and easy-to-use device that can be used to connect body tissue inside the body.

In accordance with the invention, two rotor elements are provided which are pivotable about an axis parallel to the main sections of the tissue staples and which each have a bearing surface for an engagement section of a tissue staple in order to rotate the said tissue staple from the storage position into an operating position in which the tissue staple is arranged in a further plane which is oriented substantially perpendicularly to the first plane, and a slider is provided in order to advance the tissue staple present in the operating position in the further plane and to deform it into a clamping position.

It is an essential aspect of this invention that the individual tissue staples are actively rotated by rotor elements from the plane in which they are stacked in the magazine (storage position) to the plane in which they are advanced to penetrate the body tissue (working position).

The rotation takes place about an axis, which is perpendicular to the longitudinal axis of the device and to the feed direction of the tissue staples.

A further important aspect of this invention is that a slider assumes the task of advancing a tissue staple as well as the task of deforming it after penetrating the body tissue in order to establish a secure connection. In this way, the number of components required can be kept to a minimum and the device can be designed to be particularly compact.

It is advantageous if a rotor spring acts on one rotor element in each case in order to make its movement latchable in two rotational positions, and that the rotor elements are preferably connected to a shaft. In this way it is possible to make the drive of the rotor elements simple and provide it with sufficient tolerances, since the exact angular position of the rotor elements in the critical positions, i.e. the reception and delivery of the tissue staples, is guaranteed by the latching.

A particularly elegant way of ensuring the feed of the tissue staples in the magazine and the necessary contact force on the rotor elements is to pretension the tissue staples in the storage position against the rotor element by at least one storage spring via a storage slider, wherein the storage spring preferably is attached to the shaft of the rotor elements. The storage spring is a leaf spring which is pretensioned into the wound position. It always strives to shorten the linear section parallel to the magazine and wind itself around the shaft. The particular advantage of this solution is that the force applied to the storage slider is independent of the position of the storage slider, i.e. said force remains essentially the same from the first to the last tissue staple.

A particularly high degree of compactness can be achieved by the rotor elements being driven by at least one connecting rod, which is articulated to them and which is preferably connected to the slider via a connecting slider. In this way, it is possible to drive both the slider and the rotor elements with a single drive element, thus eliminating the need for additional effort for any synchronization of different drive elements.

It is particularly advantageous in this context if the rotor elements are each driven by a connecting rod and preferably each connected to the slider by a connecting slider. This ensures symmetrical force application.

An optimum sequence of the individual movements is achieved in particular in that the connecting slide(s) is/are firmly connected to the slider and that an elongated hole is arranged at each connecting slider, in which a pin of the connecting rod engages.

The elongated hole ensures that in a first phase of the forward movement only the slider is advanced, while the pin of the connecting rod slides backwards in the elongated hole of the connecting slider so that the connecting rod and thus the rotor elements are not moved. This phase is completed when the cone has arrived at the rear end of the elongated hole. In a second phase of the forward movement, the connecting slider now takes the connecting rod with it and in this way causes the rotor elements to rotate.

During the backward motion, at first only one movement of the slider can be observed in an analogous manner, while the pin of connecting slider glides ahead within the elongated hole, so that here too no movement of the connecting rod and rotor elements occurs. Only when the pin is in contact with the front end of the elongated hole will the connecting rod be entrained and the rotor elements are turned back.

A particularly preferred embodiment variant of the present invention provides that a slider is movably arranged on the side of the main sections of the tissue staples facing away from the engagement sections in the direction of the longitudinal axis, which slider has two lateral feed regions at its front end face, between which a substantially rectangular recess is provided, and that a retaining element is provided which engages in the recess of the slider in order to deform the linear main section of an interposed tissue staple when the slider is advanced.

It is an important aspect of this invention that the slider can both feed the tissue staples and deform them in a single movement. It is advantageous that the force on the respective tissue staple is exerted directly in the area of the engagement elements during the feed so that these can be advanced against the resistance of the body tissue without first causing a deformation of the tissue staple. Only when the tissue staple has penetrated sufficiently deeply into the body tissue does the middle section of the main section of the tissue staple come into contact with the retaining element, so that the tissue staple is bent around the edges of the retaining element.

After the tissue staple has been properly placed in the body tissue, a safe detachment from the device according to the invention must be ensured. In accordance with a preferred embodiment variant of the present invention, this is achieved by arranging an ejection spring in such a way that it removes a deformed tissue staple from the retaining element. A particular advantage of this solution is that the tissue staple is stripped fully automatically, without any special control effort.

Stripping is achieved in a particularly simple way in that the ejection spring protrudes into the movement area of the slider in a force-free state. By pushing the slider forward, the ejection spring is pretensioned and by pulling the slider back, the spring is released to strip off the tissue staple.

A particularly safe guidance of the tissue staple can be achieved by providing a lug on the slider which supports the tissue staple to be advanced against the pretension of the ejection spring.

An optimal configuration of the tissue staple in the applied state is achieved in that the recess is essentially rectangular.

A particularly compact and space-saving design of the device according to the invention can be achieved in that the slider is formed in a plate-shaped manner and the range of movement of the slider lies in a plane which lies in the storage position in the region of the tips of the engagement sections of the tissue staples, and particularly preferably lies substantially parallel and at a constant distance from the main sections of the tissue staples in the storage position. In this way it is possible that the slider and other components used to drive the slider use the space that is defined by the tissue staples in the storage position in the magazine.

A particularly efficient operation of the device is achieved in that the slider has a front position and a rear position, wherein in the front position a deformed tissue staple is clamped between the slider and the retaining element, and in the rear position a tissue staple rotated from the storage position to a working position perpendicular thereto is receivable.

An important aspect of the present invention is provided in particular that a hydraulic cylinder and/or a piston rod are arranged at least partially inside the space between the engagement sections of the tissue staples in the storage position, and preferably that the piston rod is fixedly connected to the slider.

The hydraulic drive via a hydraulic cylinder, which enables the necessary forces to be applied independently of the distance to an operating element, is essential here. Since the tissue staples partially surround the hydraulic cylinder or the piston rod in the storage position, a special level of space saving is achieved.

In particular, the device can be made particularly compact in that the hydraulic cylinder is formed in a double-acting manner.

A particularly favored embodiment variant of the invention provides at least one channel for accommodating an instrument. Such known holding instruments can be advantageously used to hold tissue or to manipulate its position in order to be able to use the tissue staples optimally.

Preferably, two channels are provided, which preferably diverge slightly towards the front, wherein the angle between the channels is particularly controllable. This allows more distant tissue to be pulled up appropriately.

In particular, the manipulation of body tissue can be made particularly flexible if the holding instruments can be controlled independently of each other.

A particularly compact construction of the device according to the invention can be achieved in particular in that the channel is preferably arranged adjacent to the hydraulic cylinder and/or that the channel is arranged between the side parts.

It is particularly advantageous if the channel is located in the proximal area of the head part. This leaves space underneath the tissue staples in their storage position, so that the holding instruments can be pushed forward from the divergent channels to the side, even outside the cross-section of the device, in order to be able to also grasp lateral areas of the body tissue and pull them into the area of the tissue staples.

DETAILED DESCRIPTION

FIG. 1toFIG. 5show the head part100of a device according to the invention, which can eject and deform a tissue staple1with a linear main section2and two parallel engagement sections3(visible inFIG. 5) projecting vertically from it.

The device has a support element4on which two side parts5, a hydraulic cylinder6with a cylinder rod10and a retaining element22are arranged. On support element4, tissue staples1with their engagement sections3rest in a storage position7, which is partially illustrated inFIG. 2.

The side parts5each have a recess39, the main part of which is rectangular and is intended to receive the engagement sections3of the tissue staples1in the storage position7and to guide them up and down. In addition, the respective rotor element9is accommodated in the recess39.

In storage position7, the tissue staples1are essentially stacked on top of each other, wherein the planes7a, in which the main section2and the engagement sections3are located, are parallel to each other. In addition, the planes7aare essentially perpendicular to the axis6aof the hydraulic cylinder6, which is also the longitudinal axis of the device. This enables the tissue staples1to be arranged in storage position7in such a way that the space formed between the engagement sections3of the tissue staples1in storage position7can at least partially contain the hydraulic cylinder6or the cylinder rod10. This enables a very compact and space-saving design.

The tissue staples1in storage position7are pressed by a storage slider8against two rotor elements9which are connected to a shaft12. The pretension required for this is generated by two storage springs11. These are designed as unwound spiral springs, one end each is attached to the shaft12, the other ends to the storage slider8.

Each of the two rotor elements9is rotatably mounted and has a bearing surface13with a support lug16for an engagement section3of a tissue staple1and a recess14. A rotor spring15can engage in the recess14to allow latching to define positions of the rotor elements9. The rotor spring15is designed as an extension of the side part5.

A slider17is attached to the cylinder rod10and has two feed regions19with lugs18. There is a central rectangular recess20between the feed regions19. The slider17can be moved along the longitudinal axis6avia the hydraulic cylinder6.

In a first orientation of the rotor elements9, the bearing surfaces13face in the direction of the tissue staples1in storage position7. The storage slider8presses in this case a first tissue staple1against the bearing surfaces13. Now the rotor elements9can be turned by about 90°. The tissue staple1resting thereon is co-rotated by the support lugs16to reach a working position29, in which it is arranged in a further plane29a, which is parallel to the longitudinal axis6a. During the first part of the rotation, the first tissue staple1is pressed against the bearing surfaces13by the storage slider8, during the second part of the rotation, the surface pressure is maintained by the rotor spring15in order to hold the first tissue staple1in a defined position. The hydraulic cylinder6is at this time in a retracted position, the slider17is therefore behind the main section2of the first tissue staple1.

Now the hydraulic cylinder6can be extended. The slider17takes the first tissue staple1with it. The position on slider17is secured by an ejection spring21pressing the first tissue staple1against the lug18. At the same time, the ejection springs21are increasingly pretensioned by the feed.

The first tissue staple1is now pressed against the retaining element22, which is centered and adapted to the width of the recess20of the slider17. This deforms the first tissue staple1on the main section2into a rectangle.

When the hydraulic cylinder6is subsequently retracted, the pretension of the ejection spring21is transferred to the first tissue staple1and thus stripped off by the retaining element22.

The rotor elements9are each rotated by a connecting rod23articulated to them, which has a first pin30, which engages in an eccentric bore31of the respective rotor element9. One connecting slider24each connected to slider17has an elongated hole25in which a second pin26of the connecting rod23engages. The connection in an elongated hole25ensures that the rotation of the rotor elements9takes place in a second phase of the movement of the slider17.

In the following, the other components of the device according to the invention are briefly explained:

Cover plates32are fitted laterally outside the side parts5to cover their recesses33. The cylinder rod10is sealed by seals34against the hydraulic cylinder6, which is fastened to the support element4by mounting elements35. Hydraulic connections36and37are used to supply the hydraulic medium to control the device. A mounting bracket is designated with reference numeral38.

To illustrate the operation of the device,FIGS. 6 to 9show the same longitudinal section in different positions of the hydraulic cylinder6.

FIG. 6shows the initial condition with hydraulic cylinder6with fully extended cylinder rod10. Pin26is in the extension-side stop27of elongated hole25, the bearing surface13of the rotor elements9is parallel to the longitudinal axis6a. The slider17is in the fully extended position in which a tissue staple1(not shown here) has just been ejected.

Starting from this position, the cylinder rod10is retracted, the slider17moves to the right in the diagram, the connecting slider24connected to it also moves with it. In the first part of the extension process, no movement is transmitted to the connecting rod23, since the pin26moves in the direction of the stop28on the entry side of the elongated hole25of the connecting slider24. After about half the stroke, the stop28on the entry side is reached, and the connecting rod23is now moved with the slider17and the connecting slider24. In this way the rotor elements9are turned by about a right angle so that a first tissue staple1, which lies on the bearing surfaces13in the storage position, is turned from a vertical position inFIG. 6to a horizontal position in which it lies in the plane of the slider17. The tissue staple1, which rests on the bearing surfaces13, is entrained by the support lugs16of the rotor elements9. Since the slider17has already retracted behind the rotor elements9at this point, the movement path for the tissue staple1is free.

The position thus achieved with the cylinder rod10fully retracted is shown inFIG. 7. Now the cylinder rod10can be extended again from the hydraulic cylinder6. The slider17moves again with the connecting sliders24in the direction of the position ofFIG. 6. Again initially no movement is transmitted to the connecting rods23, as the pin26is pushed in the elongated hole25in the direction of the stop27on the extension side. When the stop27on the extension side is reached, as shown inFIG. 8, the connecting rods23move with the cylinder rod10, whereby the rotor elements9are turned back to the position shown inFIG. 6, which corresponds to the position shown inFIG. 10. During the extension movement of the cylinder rod10, which starts fromFIG. 7and ends inFIG. 9, the slider17is pushed forward to deform and eject the tissue staple1inserted in the phase betweenFIG. 6andFIG. 7. In the position shown inFIG. 9, the rotor elements9are again in the position to receive another tissue staple1.

When the slider17is fed, the ejection springs21are pretensioned via the tissue staple1in working position29, wherein the lugs18on the slider17support the tissue staple1in working position29at the bottom, so that the tissue staple1is guided on both sides. When pulling back the slider17, the support of the tissue staple1from below is omitted so that the ejection springs21push it downwards and strip it off from the retaining element22.

The working cycle can be restarted after reaching the position shown inFIG. 9.

FIG. 10toFIG. 13show two different embodiment variants of a rotor element9. The first embodiment variant shown inFIG. 10andFIG. 11corresponds to the rotor element9used and shown in the embodiment variants ofFIG. 1toFIG. 9.

This first embodiment variant has a bearing surface13, which forms part of a circular segment in relation to circumference43. A lug13ais provided at one end to entrain the tissue staple1, which in its storage position rests with its engagement section3against the bearing surface13, when the rotor element9is rotated. The bearing surface13does not extend over the entire thickness of the rotor element9. A web40remains on one side, which guides the engagement section3of the adjacent tissue staple1laterally. In the region of this web40, a first recess41is provided and, as viewed from the center of rotor element9, a second recess14is designed on circumference43at a right angle thereto. The two recesses41,14are used to latch the rotor spring15and to determine the end positions of the rotation of the rotor element9. The eccentric bore31is used for rotation through the connecting rod23. The bore42is intended for fitting onto the shaft12.

In the alternative embodiment variant shown inFIG. 12andFIG. 13, the bearing surface13extends over the entire thickness of the circumference43. The lateral guidance is assumed by the cover plates32. In addition to the bearing surface13, a further contact surface44at right angles to the circumference is preferably provided, against which the tissue staples1rest in the storage position7when the bearing surface13is turned into the ejection position (parallel to the longitudinal axis6a). With this embodiment variant, the engagement sections3of the tissue staples1, which rest against the bearing surface13or the contact surface44and are pressed on by the storage springs11, define the end positions of the rotation of the rotor element9. Therefore, recesses are not required here.

FIG. 14shows a longitudinal section of an embodiment variant of the device according to the invention using the rotor elements9ofFIG. 12andFIG. 13. This variant largely corresponds to the embodiment variant shown inFIG. 1toFIG. 9. It can be seen that the engagement section3of a first tissue staple1on the bearing surface13is already present in the working position29. A further tissue staple1with its engagement section3rests on the further contact surface44and is pressed against it by the storage slider8so that the rotor element9is fixed in this position in a resilient manner. After ejecting the first tissue staple1, the rotor element9is turned back clockwise, wherein the storage slider8together with the tissue staples1in storage position7must first be pushed back against the resistance of the storage springs11however.

FIG. 14also shows that the engagement sections3of the tissue staples1in the storage position7(a tissue staple1is shown with interrupted lines correspondingly) extend upwardly well beyond the lower section of the cylinder rod10, which means that in the extended position the cylinder rod10moves within the rectangular space spanned on three sides of the main section2and the two engagement sections3of the tissue staple1.

FIG. 15shows a first variant of the use of a device according to the invention. The head part100is detachably mounted on a standard endoscope101with a bent portion102and is controlled by hydraulic hoses103and104, which are inserted into a body opening parallel to the endoscope.

FIG. 16shows an alternative variant of the use of the device according to the invention, in which the head part100forms the tip of an independent flexible instrument105. According to standard designs has at least one channel through which an endoscope107with a bent portion102can be inserted. The endoscope107is led out laterally with a separate bent portion106in order to be able to observe the process of stapling.

The embodiment variant ofFIG. 17andFIG. 18differs from the variants described above in that two channels50,51are provided below the hydraulic cylinder6. Channels50,51are directed outwards towards the distal end, i.e. divergent, wherein the angle of divergence is preferably adjustable. If holding instruments are now pushed through the channels50and51forward in each case, then these come out slightly directed outwards, wherein thus the variable extension increases by the distance to the point, thus increasing the space underneath the tissue staples1in their storage position7.

Due to the special design of the device, it is possible to arrange the channels50and51within the circular cross-section defined by the other components.

The present invention makes it possible to connect tissues inside the body with tissue staples, wherein it is particularly advantageous that a number of tissue staples can be used one after the other without the need to pull the device out of the patient's body and then reinsert it again.