EP3160377A1 - Electrosurgical instrument and jaw part for same - Google Patents

Abstract

An electrosurgical instrument is disclosed having a jaw part composed of instrument branches which are movable towards each other and on each mutually facing side of which one or more electrode surfaces are arranged/formed, wherein the movement of the instrument branches relative to each other can be limited by at least one proximal spacer acting on proximal end portions of the instrument branches, at least one medial spacer acting on a medial portion, and at least one distal spacer acting on distal end portions of the instrument branches. According to the invention, the proximal and/or the distal spacer are made of electrically non-conductive material and the at least one medial spacer is composed of at least one electrode made of an electrically conductive material and connected electrically conductively to the electrode. Furthermore, the at least one medial spacer interacts with a local insulation component made of a non-conductive material, which insulation component is arranged in an electrically insulating manner on at least one opposite electrode.

Description

 description

Electrosurgical instrument and jaw part for this

The present invention relates to an electrosurgical instrument,

in particular for laparoscopic interventions, with a jaw part of mutually movable instrument branches, on whose mutually facing sides in each case at least one electrode surface is arranged / formed, the movement of the instrument branches relative to one another by a proximal end sections of the instrument branches acting proximal spacers, one on distal

End portions of the instrument industry acting distal spacers and at least one acting on a medial portion of the instrument brachial medial spacers is limited.

After surgical removal of a hollow vessel section, e.g. at a

Intestinal resection due to a tumor-affected part of the intestine, the two hollow vessel sections must be reconnected at their open ends so that a continuous course is formed. This is called an end-to-end anastomosis. By default, the two opened ends are e.g. sewn together with staplers again. Especially in thin and

Dickdrmeingriffen it sometimes comes to leaky seams

(Suture insufficiency), which is associated with a serious disease course and also a high mortality rate.

An alternative to the sewing of hollow vessel sections is the so-called Tissue Fusion Technique (TFT). TFT by means of high-frequency technology (HF) is based on a denaturation of proteins contained in many tissues. This makes it possible to weld collagen-containing tissue. The tissue is heated during the welding process to temperatures above the protein denaturation temperature and brought into a gel-like state together with the intracellular and extracellular matrix. Upon compression of the tissue surfaces, the liquefied tissue cools to a fused mass, causing a secure connection of the tissue. For welding hollow vessel sections, tissue caught between two clamping jaws is subjected to a current which flows between electrodes on the two clamping jaws. In order to prevent the sealing or welding from failing, it is necessary to record and regulate parameters which act on the fabric and are present during welding. To ensure this, you need precise control of temperature, pressure, tissue impedance and distance and location of the jaws.

In addition, it is desirable to uniformly treat tissue held between the jaws so that all areas are reliably reached and no area is over-energized. For this purpose, it must be ensured that the HF electrodes are evenly spaced from each other or

are aligned parallel to each other.

The prior art does not disclose any instruments of suitable size for use with the above-mentioned hollow vessels and tissue types. In coagulation instruments of smaller design, such as e.g. In EP 1 747 762 A2, due to the design, when closing the clamping jaws a non-parallel alignment of the HF electrodes occurs, for example as a result of bending. This leads to a reduction of the distance between the electrodes, in the

worst case can cause short circuits.

Basically, the distance between the electrodes through at the

Clamps attached spacers are maintained. However, if a larger number of spacers are provided on the jaws, as e.g. In EP 1 656 901 B1, EP 1 952 777 A1, EP 1 372 507 A1 or US 2004/122423 A1, the spacers inevitably perforate the tissue to be treated, since the tissue under the spacers is compressed with closed clamping jaws in such a way that it comes to permanent tissue damage. This has a negative impact on the result of the seal.

If the pressure of the jaws is reduced to avoid perforation of the tissue and the tissue is merely pinched under the spacers, this leads to an angular deflection of the jaws. Furthermore, since the spacers are made of electrically nonconductive material to avoid a short circuit between the RF electrodes, a so-called coagulation shadow, ie the tissue sections in the region of or under the spacers, is encapsulated in the area of these spacers, thus not or only Insufficient power is applied to it and there is no satisfactory welding of the vessel sections. In addition, it has been found that such, electrically non-conductive spacers, in particular when they are attached to the electrode, for example by gluing, can easily flake off, in order to then possibly go unnoticed in the patient's body. In addition, the predefined electrode spacing is no longer guaranteed.

Against this background, the object of the present invention is to provide an instrument which improves the result of an end-to-end anastomosis of hollow vessels, in particular of hollow vessels such as small and large intestine, or generally in tissue connections by means of a thermofusion technique, in particular ensures a parallel alignment of the RF electrodes without damaging the tissue and has increased reliability.

Summary of the invention

The object is achieved by an electrosurgical instrument with a jaw part of mutually movable instrument branches, on whose mutually facing sides in each case one or more electrode surfaces is or are or is or are formed, wherein the movement of the instrument branches relative to each other by a proximal to End portions of the instrument industry acting proximal (first) spacers, one acting on distal end portions of the instrument branches distal (second) spacers and at least one acting on a medial portion of the instrument brachial medial (third) spacers is limited, wherein the medial spacer is formed by at one Electrode made of their electrode surface elevating stop made of electrically conductive material and is electrically connected to the electrode and connected to an electrically insulating insulating component on the Elek trodenfläche the opposite electrode cooperates and the proximal spacers and / or the distal spacer are of electrically non-conductive material. Advantageous developments are the subject of

Dependent claims.

An inventive coagulation instrument for surgical purposes of the pertinent genus has in one embodiment against each other (preferably scissor or mouth-like) movable instrument industries, each with one or more electrode surfaces on the respectively facing industry sides.

Between these tissue can be trapped and treated electrothermally. The movement of the instrument branches relative to one another is limited by at least one proximal spacer acting on proximal end sections of the instrument branches, at least one second distal spacer acting on distal end sections of the instrument branches, and at least one medial spacer acting on medial sections. Proximal and distal spacers are formed of an electrically non-conductive material. Medial spacers have at least one projection of electrically conductive material holding the opposing electrode surfaces at a distance from each other. This is preferably provided directly integrally with the electrode, for example by embossing or punching or formed or fixed thereto, for example by welding or soldering. On the opposite electrode is an insulating member, preferably in the form of a pad or pins of electrically non-conductive material inserted into a corresponding recess or placed / glued on / to form a contact surface for a conductive medial spacer, so that this has conductive material, the However, two opposite electrodes electrically isolated from each other.

The embodiment according to the invention ensures that the distance of the opposing electrode surfaces over the entire electrode surface is uniform. By combining conductive medial spacers with nonconductive proximal and distal spacers, the advantage can be exploited that due to the use of conductive spacers in the medial region of the electrodes, a uniform, homogeneous current distribution, in particular to a uniform current density, in between the electrodes clamped tissue comes while also non-conductive spacers in the distal and proximal marginal areas of the electrodes are placed where coagulation shadows are less relevant. It can be a uniform

Surface pressure can be achieved on the tissue to be sealed, resulting in a particularly advantageous connection of the tissue. It may be a good one

controllable and reproducible result of the sealing of said hollow vessels can be achieved. The occurrence of leaks caused by

Non-conductive spacers in the central region of the electrode, so can be particularly well avoided, with a parallel alignment of the electrodes is always guaranteed. Furthermore, by means of the non-conductive spacers in the proximal and distal edge regions of the electrodes, relatively large-area electrically insulating bearing surfaces can be formed, so that a more uniform

Electrode distance can be set and the risk of short circuits in not fully covered electrodes can be reduced. Another advantage is that the size or area of the insulation component or the insulation components of the medial

Spacer, which would have to be relatively large due to the instrument structure as a rocker to avoid short circuits, greatly reduced by the use of non-conductive spacers at the proximal and distal end of the electrode

may be formed so that the formation of coagulation can be further reduced.

In summary, among other things, the following advantages can be achieved by the invention: Safe tissue fusion by avoidance of

Coagulation shadow, secure tissue fusion by always parallel alignment of the electrodes to each other, secure tissue fusion through a clearly defined

Distance of the electrodes, prevention of tissue damage by excessive force on the clamped tissue, caused by the spacers, secure fusion of the individual tissue components by consistent

Force relationships, avoidance of electrical short circuits between the

Electrodes and prevention of short circuits in partially covered electrodes.

According to the present invention, the medial spacers on the electrode surfaces can be arranged directly or fixed on it and made of an electrically conductive material, for example in one piece / soldered / welded to the relevant electrode / connected. On or at the respectively opposite electrode is provided or arranged for each medial spacer a non-conductive insulating member on which the respective electrically conductive medial spacer is supported with the instrument closed.

The electrically conductive medial spacer is preferably knob-shaped. The electrically insulating insulating components, for example in the form of glued, applied, inserted or filled pads / plates / pins formed substantially flat to the electrode surface, so have no or only a slight projection to the respective electrode surface and can not or only with difficulty from the electrode surface be detached / demolished. Accordingly, each of the insulating components can be dimensioned smaller than an electrically non-conductive medial spacer according to the prior art in terms of the surface dimensions, since of the insulating component due to low to absent

Supernatant no shear forces must be introduced into the electrode. The medial spacers themselves can be made of a material such as metal, which withstands high shear forces, so that they can also be small in size. This contributes overall to avoid coagulation and at the same time to increase the reliability.

It is advantageous if the insulation components in the form of pads or pins are inserted into corresponding recesses or recesses (depressions) on the surface of the respective electrode, so that they are substantially planar

Form surface with the electrode (without overhang). It is also advantageous if each insulation component is designed in the form of a pin with a flat

Plate section, on the underside of a spinous process is added. This spinous process is located in a corresponding bore within the electrode and thus causes an even firmer fit / hold of the insulating component in the electrode recess.

In addition to the measures described above, it is possible to keep the number of medial spacers fixed on the respective electrode surface and thus of non-conductive insulating components used as small as possible in order additionally to reduce the effects of coagulation shadows. By providing the non-conductive proximal and distal spacers, it is generally ensured that the electrodes have a predetermined distance from each other over their entire length and thus preferably run parallel to one another. Due to the large distance of the spacers or their Einwirkstellen in industry longitudinal direction, the parallelism of the instrument industries and attached electrode surfaces is improved, as this possible manufacturing tolerances in the formation of the spacers only minor impact on the

Parallelism of industries in closed position. The thus adjustable, substantially uniform electrode spacing between the two branches in the closed position results in a uniform penetration of the tissue with HF energy and a uniform current density in the tissue.

Damage to tissue and its inhomogeneous penetration of HF energy can be further minimized in one embodiment of the invention by applying as small a number of medial spacers as possible to each electrode surface. Preferably, the instrument has two or three medial spacers, more preferably exactly one medial spacer.

The coagulation clamp according to the invention or the invention

Instrument industries of such a coagulation clamp thus provide an optimal compromise between maximum parallel alignment of the RF electrodes in the closed position of the branches on the one hand and homogeneous tissue fusion with minimal tissue damage on the other hand. Therefore, caused by the spacers tissue damage as a result of excessive force on the clamped tissue prevented and a secure fusion of the individual tissue components by constant force ratios, by the parallel arrangement of the electrodes, by the well-defined spacing of the electrodes and by the homogeneous current distribution in the tissue along ensures the electrodes. In addition, due to the special arrangement of the non-conductive proximal and distal spacers, the

can be arranged or formed in particular outside the electrode surfaces, short circuits between the electrodes and leaks on the sealed tissue layers avoided. This creates the same conditions for HF surgery, in particular with regard to tissue impedance, so that the quality of the sealed tissue areas can be better controlled electrically.

According to another or additional aspect of the invention, the

Spacers of electrically nonconductive material are disposed only outside of an area provided for the treatment of the tissue at the proximal and distal ends of the branches. When non-conductive spacers act only on the proximal and distal end portions of the instrument branches and are free of non-conductive spacers in the medial area of the instrument branches, which is typically the actual treatment area of the tissue, they are typically caused by them

Coagulation shadows avoided in this main area.

According to another or another aspect of the present invention, at least one spacer, in particular the proximal spacer, is realized in the form of a spacer module formed separately from the instrument branches. This can have at least one electrically non-conductive material tongue, which is clamped in a closed position of the instrument industries between them. The height of the material tongue therefore corresponds to a predetermined

Adjustment (parallel) distance between the instrument branches.

A separate spacer module of this type has several advantages. On the one hand, this can be done easily and independently of the respective one

Instrument industries or the coagulation clamp for which it is to be used. On the other hand, this can be exchanged at any time, be it off

Wear or replacement with another spacer module with higher or lower material tabs. This allows the distance of the

Instrument industries in the closed position can be varied. The physical separation of instrument branches and spacers thus has the advantage that the same spacer module can be provided for different instrument branches or different spacer modules for the same instrument branches. Also, the coagulation shadow effect is less in the case of a loosely held and between the electrode surfaces in the closed position of the industries clamped material tongue, as in the case of one on the electrode surfaces fixed spacer, even if the spacer is made of electrically conductive material and cooperates with an insulating member made of electrically non-conductive material.

The spacer module may have a plurality of laterally or transversely of the

Branches spaced apart material (of non-conductive material) have, for. to save a provided between two Koagulationselektrodenflächen electrical cutting section.

For opening and closing the instrument industries, at least one of the instrument branches can be pivotally mounted, for example, on an instrument shaft or on the opposite branch and can be actuated via a handling mechanism (mounted in the instrument shaft and / or in the grip) in order to move the instrument sectors counter to and away from each other. The spacer module can rotatably in a pivot joint of the actuated (stored)

Be stored instrument industry, in particular case-like encompassed by joint sections of the actuable instrument industry.

The integration of the spacer module in the pivot joint of one or both instrument industries this is not only saving space inside the

Instruments and the jaw part, but exercises his

Spacer function without additional operator intervention by itself when the instrument branches are closed.

Alternatively or in addition to the above-mentioned separate spacer module, at least one of the instrument branches, preferably the pivotable one, may be used

Industry one led in a backdrop on the side of the other industry

Have Drehbegrenzungsstift, the interaction of Drehbegrenzungsstift and backdrop a kind of spacer, in particular on the proximal

End sections of the instrument industry acting spacers simulated or

forms and the instrument industries to each other occupy a predetermined distance when the at least one rotation limiting pin reaches an end portion of the gate. In the event that both instrument branches are pivotable or otherwise movable (eg displaceable) are stored, the degree of freedom of both Instrument industries each guided by one in a particular backdrop

Be limited rotation limiting pin.

In particular, this solution has the advantage that the spacer, at least in the proximal end portion of the branches, is completely outside the clamping area of the instrument branches, i. outside the tissue treatment area

(Electrode surfaces) can be arranged and there is no contact between the spacer and the tissue to be treated. In this way damage to the tissue can be safely prevented.

A spacer, in particular the distal spacer, can be formed by a (knob-shaped) projection arranged outside the electrode surfaces, in particular between two electrode surfaces, and pointing towards the other instrument branch. Consequently, if this spacer is not arranged on the electrode surfaces, but next to or in between, no coagulation shadows develop in this region, in particular because then the spacer (s) need not be made of insulating material. When the spacer is disposed between the electrode surfaces, particularly when it is disposed on the central axis of one of the instrument branches, without direct contact with the electrode surfaces, there is no electrical

Short circuit between the electrode surfaces. In addition, no results

Torsionsbeanspruchung the instrument industries when they are pressed against each other in the closed position and held apart only by the spacer. As a result, the number of spacers can be further reduced overall.

One or more spacers may be formed by only one protrusion directly provided / fixed on an electrode surface or by a plurality of respectively different electrode surfaces. This ensures, on the one hand, a parallel alignment of the electrodes in the longitudinal direction and, on the other hand, keeps the number of spacers fixed on the electrode surfaces small, whereby an optimal treatment, in particular a homogeneous fusion of the

Tissue is possible. Between the proximal, medial and distal spacers, at least one instrument sector may additionally comprise one or more knob-shaped elevations whose height is less than the height of the spacers, in particular 10% to 75% of the height of the spacers Spacer is. By means of these elevations or teeth, the tissue can be better held to prevent the tissue or tissue sections to be treated from slipping out of the instrument branches before they are fused together. Since this increase is lower than the distance defined by the spacers of the two

Instrument industry in the closed position, e.g. 10% - 75% of the distance, these never come into contact with the opposite instrument industry. Therefore, the tissue between the elevation and the opposite

Instrument industry not perforated and thus not permanently damaged. Furthermore, no coagulation shadows are produced by these elevations, since the tissue clamped between the elevation and the opposing instrument industry is not substantially covered. The coagulation shadows created by the conventional instruments are thus avoided. Since these increases do not come into contact with the opposite instrument industry anyway, they can also be made of electrically conductive material, in which case can be dispensed with opposite pads / pins of electrically non-conductive material. Of course, several such elevations can be arranged per electrode surface. These can be arranged at regular intervals.

It should be noted that the aforementioned aspects and features can be combined individually as well as with several others.

Brief description of the drawings

Fig. 1 shows an electrosurgical instrument according to a first

Embodiment of the invention;

Fig. 2 shows an electrosurgical instrument according to a second

Embodiment of the invention; 3 shows a perspective view of two (scissor-like) pivotable instrument branches of the electrosurgical instrument with an enlarged view of a spacer module;

Fig. 4 shows a side view of the two instrument branches of Figure 3 in an open position.

Fig. 5 shows a side view of the two instrument branches of Figure 3 in a closed position.

Figures 6A, 6B, 6C show detail views A, B and C of Figures 4 and 5, respectively.

7 shows a perspective view of two instrument sectors of an electrosurgical instrument which can be pivoted relative to one another according to the invention;

Fig. 8 shows a side view of the two instrument branches of Fig. 7 in a closed position;

Figs. 9A, 9B and 9C show detail views A, B and C of Fig. 8;

Figures 10, 11 and 12 show medial spacers in different

Detailed views;

Fig. 13 shows an electrosurgical instrument according to another

Embodiment of the invention;

Fig. 14 shows the detail view of a spacer and an insulating member according to a first embodiment of the invention;

Fig. 15 shows the detail view of a spacer and an insulating member according to a second embodiment of the invention; and

Fig. 16 shows a detailed view of a spacer and an insulating member according to a third embodiment of the invention. Detailed description of preferred embodiments

Fig. 1 shows a perspective view of a laparoscopic

electrosurgical instrument 1 according to a first embodiment of the invention with a jaw part consisting of a pair of preferably scissor or forceps like each other moving instrument branches 2 and 3 in an open

Position, which are arranged at the distal end of an instrument shaft 4, which in turn is rotatably mounted via a manually operable shaft rotator 5 to a handle or handling part 6. About the shaft rotator 5, the shaft 4 and arranged thereon Instrument industries 2 and 3 are rotated relative to the handling part 6 about the shaft longitudinal axis. The handling part 6 has a manually operable handle or trigger guard 7, which is pivotally movable relative to a handpiece or pistol grip 8 fixedly connected to the handling part 6. The instrument branches 2, 3 or at least one manually operable instrument branch 3 are connected via a (not shown)

Actuating mechanism, e.g. a cable or a push rod within the instrument shaft 4, in operative connection with the handle e and can be brought by manual operation of the handle 8 preferably continuously from an open to a closed position (and vice versa). Via a line or electrical wiring 9 (only partially shown), the handling part 6 is connected to an RF energy source (not shown) in order to apply an RF voltage to the electrothermal treatment of tissue between the instrument branches 2 and 3.

With regard to the basic mode of operation and the mechanical structure of the instrument 1, in particular of the actuating mechanism, reference is made, for example, to the published publication WO 201 1/097469 A2.

3 and 4 now show the distal end of the shaft 4 and the jaw part connected to the shaft 4 with the instrument branches 2 and 3 in an open position in detail. The first, as shown in FIG. 3 or 4 upper

Instrument industry 2 is pivotable about a transverse axis A at the distal end of the shaft 4 via a proximal pivot hinge or hinge 10 (see FIG. 4) stored. For this purpose, the distal shaft end or jaw part connected thereto has a centrally formed passage slot or longitudinal gap 11 extending along the shaft, whose side cheeks each have a (co-axially aligned) transverse bore which defines the aforementioned transverse axis A. The passage slot 1 1 further has a slot width which allows the movable / pivotable insertion of the first instrument industry 2 therein. In axial, distal

Extension (projection) to the through slot 1 1, the distal shaft end or jaw part forms a half-shell or channel-shaped support projection or support 12, which is opposite the rotatable upper instrument industry and at its distal end portion has a passage transverse bore, substantially parallel to the transverse axis A.

The second, as shown in FIG. 3 or 4 lower instrument industry 3 is in

Shaft longitudinal direction seen only over a partial length section in the

cupped support projection 12 (axially) received, so that it protrudes over the remaining part length section axially beyond the support projection 12 in the distal direction. Furthermore, the lower instrument industry 3 is pivotally articulated centrally on the support projection 12 via the distal through-cross bore in the manner of a rocker. By means of a spring mechanism not shown (see, inter alia, also WO 201 1/097469 A2) is the front or distal rocker part of the lower

4 upward or to the upper instrument industry 2 towards biased, whereby the lower sector 3 seen in the longitudinal direction at a slight angle to the instrument shaft 4 and the support projection 12 and thereby in the case of folding or closing of the jaw part, the distal End sections of the two branches 2, 3 come tweezer-like first in clamping contact. This facilitates the gripping of tissue. The lower one

Instrument industry 3 is only so far on the section or support projection 12th

rocker-shaped pivotally held about the axis B defined by the passage cross-bore to smaller angular deviations between the upper and lower

Instrument 2 and 3 in closed position to compensate or to achieve a parallel alignment of both sectors 2, 3.

Each of the instrument branches 2 and 3, according to the present

Embodiment preferably two in the sector transverse direction from each other spaced, in industry longitudinally substantially parallel

Electrodes or electrode surfaces 14, 15, 16, 17, which can be acted upon with RF voltage. As a result, tissue is between the

Instrument industries 2 and 3 in their closed position, the surgeon can coagulate this with the electrode surfaces 14, 15, 16, 17, separate or welded. A special electrosurgical knife (not shown) or a corresponding cutting device, which is electrically insulated from the electrode surfaces 14, 15, 16, 17, can also be arranged between the electrode surfaces 14, 15, 16, 17.

In order to avoid a short circuit between the electrode surfaces 14, 15, 16, 17 of the two instrument branches 2 and 3 or to ensure that a homogeneous current flows across the gap between the electrode surfaces 14, 15, 16, 17

If trapped tissue flows over the entire length of the electrode, the

Electrode surfaces 14, 15, 16, 17 remain substantially evenly spaced from each other in the closed position. The instrument 1 therefore has at the distal end portion of the lower instrument industry 3 (and / or the upper

Instrument industry 2) between the two electrode surfaces 16 and 17 beyond the electrode surfaces 16 and 17 by a predetermined and the desired distance between the electrode surfaces 14, 15, 16, 17 corresponding extent

projecting, preferably knob-shaped projection 18 which is connected to the upper

Instrument industry 2 (and / or the lower instrument industry 3) comes into abutment when closing the jaw part and so as a spacer to the distal

End sections of the two instrument industries 2 and 3 is used. At the proximal end portions of the two instrument branches 2 and 3, the distance between the electrode surfaces 14, 15, 16, 17 according to this embodiment is separated by a separate, i.e. separated from the branches 2, 3 or the electrodes 14, 15, 16, 17 freely held spacer module 19 accomplished. This spacer module 19 is presently a cam-shaped component with a proximal bearing portion (cam portion with through-cross bore), which with the pivot joint

(Pivot pin) 10 is engageable and located between the

Instrument industries 2 and 3 thus can rotate freely about the pivot axis A. For reasons of space, in the present case the movable upper (and / or the lower) sector 2 is hollowed out at its proximal end section in the region of the pivot axis A in the longitudinal direction, resulting in a type of receiving space or longitudinal groove which Dimensions for receiving therein the spacer module 19 are sufficient. That is to say, at least in the closed position of the jaw part, the spacer module 19 is accommodated between two slot cheeks of at least one actuatable instrument branch 2.

Fig. 3 shows an enlarged perspective view of the spacer module 19 alone. As already indicated above, the module 19 has a camshaft shape with the proximal bearing portion in which the cam has such a cam thickness / height as to be retractably movable in the proximal longitudinal groove of the one branch 2. In the storage section of the module 19, the transverse passage bore 20 is further formed. On the storage section

opposite to the distal outer transverse side of the module 19 are formed two radially with respect to the pivot axis A projecting flat material tongues 21, the respective flat sides of the branches 2, 3 are facing and their

Tongue thickness / height H to be achieved minimum distance S (gap) between the opposite electrode surfaces 14 and 16 or 15 and 17 in

Closed position of the branches 2, 3 corresponds and whose lateral distance (in

Sector transverse direction) and width essentially corresponds to the parallel spacing and the width of the electrode surfaces 14, 15, 16, 17, so that the material tongues 21 at least partially come to lie on the electrode surfaces 14, 15, 16, 17.

Between the two material tongues 21, a longitudinal slot 22 open at the distal end of the module 19 is formed in the cam-shaped module 19, which extends as far as the bearing section and ends immediately in front of the transverse bore 20. The entire spacer module 19 or at least the material tongues 21 are in this

Embodiment made of electrically non-conductive material.

Figures 4 and 5 show a side view of the jaw part or the

Instrument branches 2 and 3 once in open position and once in closed position. FIGS. 6A, 6B and 6C show detailed views of the jaw part according to FIGS. 4 and 5.

In Fig. 6A it can be seen that the material tongues 21 of the

Spacer module 19 loosely rest on a proximal end portion of the electrode surfaces 16 and 17 of the lower instrument industry 3 when the jaw part in Open position is. When the instrument branches 2 and 3 are brought into the closed position (preferably Fig. 5) by operation of the upper instrument industry 2, the material tongues 21 of the separate spacer module 19 become between the proximal end portions of the electrode surfaces 14, 15, 16, 17 of the two instrument branches 2 and 3 are clamped (see FIG. 6B) and the projection 18 at the distal end section of the lower instrument sector 3 comes into abutment with the distal end section of the upper instrument sector 2. Thus, the proximal and distal end sections and thus also the entire electrode surfaces 14, 15 remain 16, 17 by the predetermined gap S of each other and substantially parallel to each other objected.

As stated above, in this embodiment, the (knob-shaped) projection 18 is interposed between the electrodes and thus comes into direct contact with the upper actuatable sector 2 (and not with the upper electrode surfaces of branch 2). In addition, the proximal material tongues 21 are not fixed directly on the electrode surfaces but are only applied to them. In the first embodiment, therefore, no spacer is located directly on one of the electrode surfaces 14, 15, 16, 17 (in the sense of being fixed thereon). With that you can

Coagulation shadow effects over the prior art can be reduced.

Fig. 7 shows an embodiment of the laparoscopic electrosurgical instrument 1 in a perspective view. FIG. 8 shows the distal end region of the instrument of FIG. 7 in a lateral view. FIGS. 9A, 9B and 9C show enlarged cutouts, which are respectively identified in FIG. Fig. 9A shows a medial spacer, Fig. 9B a distal spacer, and Fig. 9C a proximal spacer. On the electrode surface 14 of the instrument 1 at the distal end a projection 18 and on the electrode surface 17 at the distal end a projection 13 is arranged, in particular directly (ie fixed fixed) on the distal end portions of the electrode surfaces 14 and 17. The projections 13 and 18 form non-conductive distal spacers according to the invention. To a short circuit between the electrode surfaces 14, 15 on the one hand and the

On the other hand, to avoid electrode surfaces 16, 17 when they come in a closed position close to the respective opposite electrode surfaces, the projections 13, 18 made of an electrically non-conductive material manufactured. You can therefore either directly with the respective opposite electrode surface in contact and thus come into contact or indirectly, for example via insulation components not shown in Figure 7, in particular on the respective opposite electrode (exclusively) in the region of the respective projection (dot / pad-shaped) can be provided. The projections 13, 18 as well as possibly provided insulation components can be formed by spraying, applying, filling a hardening mass or by sticking or inserting a lsolationsplättchens / -pads / -pins preferably in a recess in the respective electrode, as shown in more detail below is described.

Proximal spacers in the form of material tongues 21 of a spacer module 19, which has already been described with reference to FIGS. 3 to 6, to which description reference is made, are formed in the proximal end section of the instrument branches 2, 3.

In the medial section, four equally spaced insulating components 23, 24, 25 are arranged on the electrode surface 14. On the

opposite electrode surface 16 are in a corresponding position three equally spaced, electrically conductive projections 26, 27, 28 are formed. In the medial portion of the electrode surface 15 are also three equally spaced, electrically conductive projections 29, 30, 31 formed, while on the opposite electrode surface 17 in

corresponding position three equally spaced isolation components 32, 33, 34 are formed. As can be seen in particular from FIG. 8, in the case of closed instrument branches 2, 3 the insulating component 23 reaches the

Projection 26, the insulating member 24 with the projection 27 and the insulating member 25 with the projection 28 in abutment. In a similar way get the

Insulating components and projections of the electrode surfaces 15 and 17 in mutual contact.

FIG. 13 shows an electrosurgical instrument 102 according to another embodiment, which differs from the instrument 1 described above in FIG

Instrument type, especially in the design of the actuator and the handle is different. While the above-described various Embodiments all with reference to the laparoscopic electrosurgical instrument 1 shown in Fig. 1 with a thin, long shaft 4 and pivotally articulated instrument industries 2 and 3 has been described as the distal jaw part, are the previously described variants of

Spacer arrangements also in connection with the instrument 102 can be realized, in which, however, two instrument branches 104 and 106 via a

Slider element 108 and a corresponding (not shown) facial expressions are interconnected. The handle or the handle has a kind of receiving shaft from which protrude the instrument industries axially and distally. This shaft is dimensioned so that the instrument industries in their

Pull back over the sliding element 108 into the shaft of this

be compressed. If the sliding element 108 again in the direction

Manhole opening advanced, move the instrument industries out of the shaft and open it preferably automatically, for example, due to a spring preload.

The shape and size of the chewers can be selected as desired, as long as all spacers are coordinated so that the distance between the electrode surfaces is always the same at all points. For example, the spacer can also be pyramid (dull), cylindrical or cube-shaped. The

Spacer module may eventually be arranged in several juxtaposed

Single modules are divided with only one material tongue each.

Hereinafter, a spacer 300 as an example of one of the projections 26, 27, 28, 29, 30, 31 and an insulating member 350 as an example of one of

Insulating components 23, 24, 25, 32, 33, 34 described in more detail with reference to FIGS. 14 to 16, as they are basically used in the above embodiments of a jaw member preferably on the electrode.

As has already been stated, the spacers or protrusions 300 according to the present invention are preferably formed from an electrically conductive material (ie electrically conductive), preferably integrally with an associated, associated electrode 360. The respective projection 300 can by appropriate punching and bending or by (selective) embossing / pressing out the electrode 360 itself be made. However, it is also possible in principle to weld, solder or mold the electrically conductive projection 300, for example in the form of a cone according to FIGS. 14 to 16 or a hemisphere, on the electrode 360. In this way, in each case a high strength between the projection 300 and electrode 360 and a rigid projection itself is generated, so that accidental scratching or breaking off of the projection thus formed is largely avoided.

On an opposite electrode 370 (the other branch) are formed in the region of the projection 300 plate or disc-shaped recesses or recesses 372. These recesses 372 also have a central blind or through hole 374 in the electrode 370 extending in the thickness direction of the electrode 370. In this way, in the longitudinal section according to FIGS. 14 to 16, a kind of mushroom-shaped recess is formed in the relevant electrode 370.

In this recess, a pin / plug or plug is used as an insulating member 350 made of electrically non-conductive material whose shape of the recess in

Substantially exactly adapted and defines the insulation component. Alternatively, it is also possible to inject into the recess a potting compound of electrically non-conductive material which cures thereon.

As shown in FIG. 14, the plug 350 terminates substantially flat with the surface of the respective electrode 370. In this way, the plug 350 does not form an external point of attack in order to be able to be pulled out of the recess if necessary. Furthermore, the outer surface of the plug 350 is in

Substantially matched to the opposite projection 300 and only so large that the projection 300 securely presses on compression of the two branches on the plug 350, without touching the electrode in question directly.

15 and 16 each show alternative embodiments for the plug 350 (insulating component), according to which a concave outer surface is provided on the plug 350 according to FIG. 15, which effects a better centering of the opposite projection 300 during compression of the branches or according to FIG Fig. 16 of Plug 350 is opposite the surface of the relevant electrode (slightly) reset in order to avoid a supernatant in any case.

Finally, it should be noted that the insulating component may in principle also have a different shape than the stopper 350 shown. So it is possible, the insulating component exclusively flat, i. platelet-shaped. It is also possible to make the plug 350 pyramidal or conical. As a material for the insulating component, a ceramic or a plastic offers. Also, between the insulating member (in particular the plug 350) and the

Electrode 370 may be provided an intermediate layer, the heat-related

different material expansions between the electrode 370 and the

Isolation component compensates and so breaking or swelling of the

Isolation component from the recess 372 prevented.

Claims

claims 1 . Electrosurgical instrument (1) with a jaw part of mutually movable instrument branches (2, 3), on whose mutually facing sides at least one electrode surface (14, 15, 16, 17) is arranged / formed, wherein the movement of the instrument branches (2, 3 relative to one another by a proximal spacer (21) acting on proximal end portions of the instrument branches (2, 3), a distal spacer (13, 18) acting on distal end portions of the instrument branches (4, 6), and at least one medial portion of the instrument acting medial spacer (23-34) is limited, wherein the at least one medial spacer (23-34) is formed by an electrode (360) from the electrode surface (14, 15, 16, 17) rising stop (300 ) made of electrically conductive material and electrically conductively connected to the electrode (360) and with an electrically insulating isolation construction part (350) on the electrode surface (14, 15, 16, 17) of the cooperating electrode (370); and where  the proximal spacer (21) and the distal spacer (13, 18) are of electrically non-conductive material. 2. electrosurgical instrument (1) according to claim 1, characterized in that the instrument (1) has exactly one medial spacer (23-34), preferably two or three medial spacers (23-34). 3. electrosurgical instrument (1) according to claim 1 or 2, characterized in that the insulation component (350) has a contact surface for the abutment (300) and in particular a mushroom-shaped body, wherein the areal extent of the abutment surface in the electrode plane projects beyond the abutment (300) on all sides so that the abutment (300) does not make electrical contact with the electrode (370) having the insulating member (350) is obtained. 4. Electrosurgical instrument (1) according to one of the preceding claims, characterized in that the insulating member (350) having electrode (370) has at least one recess (372, 374) on its surface into which the Insulating member (350) is inserted or which is poured with an electrically insulating material which forms the insulating member (350) after solidification. 5. Electrosurgical instrument (1) according to one of the preceding claims, characterized in that the insulating member (350), in particular its contact surface for the stop (300), just with the electrode surface (14, 15, 16, 17) is aligned or a concavity or with respect to the electrode surface (14, 15, 16, 17) is reset. 6. An electrosurgical instrument (1) according to any one of the preceding claims, characterized in that the proximal spacer (21) and / or the distal spacer (13, 18) are arranged exclusively outside of an area intended for the treatment of the tissue. 7. electrosurgical instrument (1) according to one of the preceding Claims, characterized in that  the proximal spacer through one at a proximal end portion of an instrument industry (3) between two electrode surfaces (16, 17) thereof 2), and / or the distal spacer by a distal end portion of an instrument industry (3) between two electrode surfaces (16, 17) of this instrument industry (3). 3) arranged and to the other instrument industry (2) facing out projection (13, 18) is formed. 8. electrosurgical instrument (1) according to one of the preceding Claims, characterized in that  the distal spacer and / or the proximal spacer is formed by a projection (13, 18) provided on an electrode surface (16, 17) or by a plurality of respectively different electrode surfaces (16, 17). 9. electrosurgical instrument (1) according to one of the preceding Claims, characterized in that the proximal spacer is formed by a spacer module (19) formed separately from the instrument branches (2, 3), which at least one is electrically non-conductive material tongue (21), which is clamped in a closed position between the instrument industries (2, 3). 10. electrosurgical instrument (1) according to claim 9, characterized marked that  the spacer module (19) is rotatably mounted in a pivot joint (10) of a pivotable instrument industry (2) and in particular by cheek-shaped joint portions of the pivotable instrument industry (2) is embraced, which define a receiving cavity for the spacer module (19). 1 1. Electrosurgical instrument (1) according to one of the preceding Claims, characterized in that  the height (H) of the proximal spacer, the distal spacer and the medial spacer corresponds to a predetermined minimum distance (S) between the instrument branches (2, 3) in the closed position, in particular the respective height (H) of the proximal spacer, the distal spacer and of the medial spacer is the same size. 12. electrosurgical instrument (1) according to one of the preceding Claims, characterized in that  the spacers are evenly spaced, in particular that the distances between the proximal spacer and the medial Spacers and / or between the distal spacer and the medial spacer are the same. 13. electrosurgical instrument (1) according to one of the preceding Claims, characterized in that  the spacers are formed on each electrode surface, in particular are formed identically on each electrode surface.