DE20001204U1 - Bipolar barrel instrument - Google Patents

Description

Bipolar gripping instrument

The invention relates to a bipolar grasping instrument with two clamping jaws that can be moved relative to one another, are elastically insulated from one another and can each be connected to a pole of a high-frequency electrical voltage source, each of which has two clamping elements arranged at a distance from one another and forming a longitudinal slot between them, each with a clamping surface, and with a cutting device that comprises a cutting element with a cutting edge that can be displaced into the longitudinal slot of the clamping jaws.

With bipolar grasping instruments it is possible to coagulate tissue in the grasped area so that bleeding in this area can be stopped.

It is known to use such instruments to coagulate certain areas of vessels, for example, and then to cut through the vessels in this coagulated area, minimizing the risk of bleeding through the preceding coagulation. This requires two completely separate process steps, which are usually carried out with different instruments, namely the coagulation

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ling with a bipolar grasping instrument on the one hand and severing the coagulated tissue by means of a cutting device on the other.

Bipolar grasping instruments are also known in which a cutting device is integrated (company brochure CIRCON, TRIPOLAR Cutting Forceps; US Patent 5,458,598). In this instrument, the clamping jaws of the grasping instrument are divided by longitudinal slots into two clamping surfaces arranged next to one another, and a cutting element provided with a blade can be inserted into the longitudinal slots in the longitudinal direction of the instrument, which cuts through the tissue parts held between the clamping surfaces after coagulation. In this previously known instrument, different drive mechanisms must be provided for closing the clamping jaws for the purpose of coagulation and for advancing the cutting element of the cutting device. This instrument, which is preferably designed as a tubular shaft instrument, is therefore relatively complicated, and the user of this instrument must also operate two separate drive mechanisms in order to grasp tissue one after the other and then cut it.

It is an object of the invention to design a bipolar grasping instrument of the generic type in such a way that operation is simplified, in particular because the user only needs one actuating mechanism to grasp tissue one after the other and then sever it.

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This object is achieved according to the invention in a bipolar grasping instrument of the type described at the outset in that the cutting element is arranged in the longitudinal slot of one clamping jaw in such a way that its cutting edge is received in the longitudinal slot between the clamping elements of this clamping jaw and does not protrude beyond its clamping surfaces in the direction of the other clamping jaw, and that the clamping elements of this clamping jaw are elastically movable relative to the cutting element against the closing movement of the clamping jaws to such an extent that the cutting edge of the cutting element protrudes beyond the clamping surfaces.

When the clamping jaws begin to close, the cutting element is held in the longitudinal slot of one of the clamping jaws in such a way that the cutting edge of the cutting element is inside the longitudinal slot and is therefore not effective. In this case, the instrument works like a conventional bipolar grasping instrument, where the clamping surfaces are placed on the tissue to be grasped without the cutting element even appearing. In this part of the closing movement, coagulation can be carried out in the conventional way by applying a high-frequency voltage; after coagulation, the bipolar grasping instrument can be removed again like a conventional bipolar grasping instrument.

However, if the closing movement of this bipolar grasping instrument is continued after coagulation,

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the clamping jaws are moved against each other so forcefully that the clamping elements of the clamping jaw that carries the cutting device are moved elastically against the closing movement of the clamping jaws, and this releases the cutting edge of the cutting device, which then protrudes above the clamping surface due to the elastic displacement of the clamping elements. The instrument is therefore now a cutting instrument in which the cutting element can reach the longitudinal slot of the other clamping jaw, cutting through the tissue arranged between the clamping jaws. This cutting movement follows directly on from the normal closing movement of the clamping jaws, the user only has to operate a drive mechanism, with light operation only the tissue to be coagulated is clamped and held, but with forceful closing of the clamping jaws the parts of the tissue held between the clamping jaws are also cut through.

In a first preferred embodiment, both the cutting element and the clamping elements are formed in one piece with the clamping jaws and the cutting element is a rigid part of the clamping jaw, while the clamping elements are connected to the other parts of the clamping jaw via elastically deformable regions. In particular, the elastically deformable regions can be formed by elastically bendable webs of a smaller height.

In another embodiment, the clamping jaw is designed in two parts with a

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rigid first part, which comprises the cutting element and the bearing of the clamping jaw on the grasping instrument, and with a second part, which comprises the clamping elements
and which is elastically movable on the first part.

For example, the clamping elements can be elastically pivotably mounted on the first part.

It is advantageous if the second part is U-shaped with two parallel legs forming the clamping elements and a connecting piece which closes the longitudinal slot towards the distal end of the clamping jaw.
web and when the second part is rotatably mounted on the first part at the free ends of the legs. This results in a very stable arrangement of the second part carrying the clamping surfaces
of the Kleenunbacken.

The longitudinal slot in the other clamping jaw, which does not have a cutting device, is preferably closed at both ends so that the cutting device at the
cutting process into this longitudinal slot, which is closed on all sides, this also contributes to the
other clamping jaws form a very stable arrangement.

The following description of preferred embodiments of the invention serves in connection with the
Drawing for further explanation. Shown are:

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Figure 1: a side view of a bipolar grasping instrument designed as a tubular shaft instrument with two pivoting clamping jaws;

Figure 2: a perspective exploded view of the two clamping jaws and the drive elements for the clamping jaws;

Figure 3: a side view of the instrument of Figure 1 in the jaw area with the jaws in a grasping position;

Figure 4: a view similar to Figure 3 with the

Jaws in a cutting position and

Figure 5: a perspective view of the clamping jaw provided with a cutting device similar to the view in Figure 2 in a modified embodiment of this clamping jaw.

The surgical instrument shown in the drawing is designed as a tubular shaft instrument 1 with an elongated, tubular shaft 2 with a distal end 3 and a proximal end 4.

At the proximal end 4, the shaft 2 is connected to a handle part 5, which comprises a fixed branch 6 and a pivotally connected branch 7, which is articulated with a push and pull rod

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8, which penetrates the shaft 2 and can be advanced and retracted in the longitudinal direction by pivoting the branch 7 relative to the shaft 2.

A holder 9 is inserted into the shaft 2 at its distal end 3, which has two bearing arms 10 at its distal end, which run parallel to one another and protrude in the distal direction and enclose a bearing space 11 between them. An insulating body 12 made of an electrically insulating material, for example made of ceramic, is inserted into these, which is essentially U-shaped and covers the bearing arms 10 on their inside.

The push and pull rod 8 passes through both the bracket 9 and the insulation body 12 and ends in the area of the bearing gap 11.

In the area of their free ends, the bearing arms 10 have aligned receiving openings 13 for a bearing shaft 14, which runs transversely to the longitudinal direction of the shaft longitudinal axis of the instrument and penetrates the bearing space 11 at its distal, open end.

On this bearing shaft 14, two clamping jaws 15, 16 are mounted next to each other and can pivot independently of each other, the proximal ends 17, 18 of which extend into the bearing space 11. Each proximal end 17, 18 is connected in an articulated manner to a link 19 or 20, the other ends of which are also connected in an articulated manner to the distal

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end of the push and pull rod 8, so that these links 19, 20 together with the proximal ends
17 and 18 form a four-bar linkage, by means of which the clamping jaws 15 and 16 are moved by the distance between the bearing shaft and the push and pull rod when the push and pull rod are pushed forward and retracted.
14 formed axis of rotation can be pivoted: When pushing
the push and pull rod 8, the clamping jaws
swung apart, ie opened, when the push and pull rod 8 is pulled back, a
Closing the clamping jaws 15, 16.

The clamping jaws 15 and 16 are designed differently.
One of the two clamping jaws, hereinafter referred to as the lower clamping jaw 16, is designed in three parts, it comprises a proximal section 21, which extends to immediately in front of the bearing shaft 14, a middle section 22, which is located essentially in the area of the bearing shaft 14, and a distal
Section 23, whose essentially flat upper side 24 facing the other clamping jaw 15 forms a clamping surface which is provided with transverse ribs to increase the grip
25.

The middle section 22 consists of an electrically insulating material, for example ceramic, and connects the proximal section 21 to the distal section 23, electrically insulating these two sections, which consist of metal and are thus electrically conductive. The middle section 22 lies flat against both the distal section 23 and the proximal section 21, so that in the overlap

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region, a layered structure is created, and the middle section 22 is supported by its rear edge 26 and by a front contact surface 27 on the proximal section 21 and the distal section 23, respectively, so that in this way the proximal section 21 is connected to the distal section 23 in an electrically insulating and rigid manner.

The middle section 22 has a sleeve 28 formed integrally with it on the side, which passes through bearing openings 29 and 30 in the two clamping jaws 15 and 16 and which accommodates the bearing shaft 14, which is thereby electrically insulated from the clamping jaw 15 and the proximal end 18 of the clamping jaw 16. The bearing shaft 14 itself is made of metal and is electrically connected to the bearing arms 10 of the holder 9, which in turn is electrically connected to the shaft 2. This has an electrical connection 31, with which an electrical connection can be made to a high-frequency voltage source (not shown in the drawing).

The bearing shaft 14 is in direct contact with the distal section 23 of the clamping jaw 16, so that in this area an electrically conductive connection is created between the distal section 23 and the bearing shaft 14. The distal section 23 of the clamping jaw 16 can thus be connected to a pole of the high-frequency voltage source.

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The other pole is connected to the push and pull rod 8 in a manner not apparent from the drawing, so that in this way, via the links 19 and 20, both

«r

the proximal portion 21 of the clamping jaw 16 as well as the entire clamping jaw 15 are connected to this second pole of the high-frequency voltage source.

The middle section 22, which is additionally fixed relative to the proximal section 21 by a pin 33 engaging in a bore 32 of the proximal section 21, electrically separates the distal section 23 of the clamping jaw 16 from the proximal section 21 of the clamping jaw 16, so that the two clamping jaws 15 and 16 are electrically insulated from one another and are each connected to a pole of the voltage source.

The other clamping jaw, referred to below as the upper clamping jaw 15, is made entirely of metal and is formed in one piece in the embodiment of Figures 1 to 4. A proximal section 34 is designed similarly to the proximal section 21 of the lower clamping jaw 16; it merges into a distal section 35 which has two clamping elements 37 which run parallel to one another and form a longitudinal slot 36 between them and are of the same design. Both clamping elements 37 have a clamping surface 38 on their side facing the lower clamping jaw 16, which is opposite the clamping surface 24 of the lower clamping jaw 16 and which, like the latter, is provided with transverse ribs 39.

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Both clamping elements 37 are connected to the proximal section 34 via band-shaped webs 40 of low overall height, which are designed so flat that an elastic pivoting of the arm-like clamping elements 37 is possible in this area, namely about a pivot axis which runs parallel to the bearing shaft 14.

A cutting body 41, which is rigidly connected to the proximal section 34 and whose lower edge is designed as a cutting edge 42, projects into the longitudinal slot 36 remaining free between the two clamping elements 37. When the clamping elements 37 are undeformed, i.e. when they are not elastically pivoted relative to the proximal section 34, the cutting edge 42 is located completely inside the longitudinal slot 36, i.e. it does not protrude downwards over the clamping surfaces 38 of the two clamping elements 37 (illustration in Figures 2 and 3).

If, however, the clamping elements 37 are elastically pivoted upwards, i.e. in the opening direction of the clamping jaws, then this cutting edge 42 protrudes downwards between the clamping surfaces 38 and can become effective.

A longitudinal slot 43 is also formed in the lower clamping jaw 16, which is aligned with the longitudinal slot 36 in the upper clamping jaw 15 and which is closed at both ends, the length of the longitudinal slot 43

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is dimensioned such that the cutting edge 42 of the cutting body 41 can penetrate into the longitudinal slot 43.

The instrument designed in this way serves equally as a bipolar grasping instrument and as a cutting instrument.

When the push and pull rod 8 is advanced, the
Clamping jaws 15 and 16 are initially swung apart,
the grasping forceps is in the open position. In this position, tissue to be treated, for example a vessel 44, can be grasped at the clamping surfaces 24 and 38 of the
clamping jaws are placed and grasped (Figure 3).
By applying a high frequency voltage to the two clamping jaws 15 and 16, the vessel is thus held in place by the two clamping jaws 15 and 16.
coagulation of the vessel 44 in the area of the implantation is possible,
as is known from bipolar grasping forceps.

This coagulation takes place when the clamping jaws 15, 16 are in a position where they are pivoted into an intermediate position compared to the open position, but still
are not completely closed. In this intermediate position, the contact pressure of the upper clamping jaw
15 to the vessel 44 should still be so small that the clamping elements 37 in the area of the webs 40 are not elastic
but remain undeformed, so that the cutting body 41 with the cutting edge 42 in the longitudinal slot
36 remains, the cutting edge 42 is therefore ineffective
(Figure 3).

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However, when the clamping jaws 15 and 16 are closed further by pulling back the push and pull rod 8, the clamping jaws 15 and 16 are pressed forcefully against one another, and this leads to the clamping elements 37 being bent in the area of the thin, elastically bendable webs 40, the clamping elements 37 thus pivoting upwards against the closed position, and as a result the cutting edge 42 of the cutting body 41 can emerge downwards over the clamping surfaces 38, come into contact with the vessel 44 and sever it when the clamping jaws 15 and 16 are closed further, the cutting body 41 with the cutting edge 42 dipping into the longitudinal slot 43 of the clamping jaw 16.

With the same closing movement of the pivoting branch 7, the surgeon can therefore first grasp the tissue to be treated and severed, then coagulate it by applying a high-frequency voltage and finally severe it in the coagulated area by further pivoting the branch 7. Only one drive mechanism is necessary for this, and the surgeon can carry out this process with a single lever, which he pivots according to the requirements so that the described working positions are adopted one after the other.

The embodiment of Figure 5 is constructed similarly to that of Figures 1 to 4, and corresponding parts therefore bear the same reference numerals.

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The only difference is in the area of the upper clamping jaw 15, which is made in two parts in the embodiment of Figure 5. In this embodiment, the two clamping elements 37 are not connected to the proximal section 34 of the clamping jaw 15 via elastic webs 40, but are pivotably mounted on the cutting body 41 via a bearing pin 45, specifically in the transition area of the cutting body 41 to the proximal section 34. In this embodiment, the clamping elements 37 are connected to one another at the distal ends by a crossbar 46, so that the two clamping elements 37 together with the crossbar 46 form a single component.

A spring element 47, shown only schematically in the drawing and connected on the one hand to the cutting body 41 and on the other hand to the crosspiece 46, holds the clamping elements 37 in a position in which the clamping surfaces 38 protrude downwards over the cutting edge 42 of the cutting body 41, so that the cutting edge 42 is completely received in the longitudinal slot 36 and is therefore ineffective. The clamping elements 37 can be pivoted elastically against the effect of this spring element 47 so that the cutting edge 42 emerges from the longitudinal slot 43 and becomes effective in the manner described.

In this embodiment, the clamping elements 37 are electrically connected to the proximal section 34 via the bearing pin 45, so that in this case too the clamping surfaces 38 are connected to a pole of the high-frequency voltage source.

Claims (7)

1. Bipolar grasping instrument with two clamping jaws that can be moved relative to one another, are electrically insulated from one another and can each be connected to a pole of a high-frequency electrical voltage source, each of which has two clamping elements arranged at a distance from one another and forming a longitudinal slot between them, each with a clamping surface, and with a cutting device that comprises a cutting element with a cutting edge that can be moved in the longitudinal slots of the clamping jaws, characterized in that the cutting element ( 41 ) is arranged in the longitudinal slot ( 36 ) of one clamping jaw ( 15 ) in such a way that its cutting edge ( 42 ) is received in the longitudinal slot ( 36 ) between the clamping elements ( 37 ) of this clamping jaw ( 15 ) and does not protrude beyond its clamping surfaces ( 38 ) in the direction of the other clamping jaw ( 16 ), and that the clamping elements ( 37 ) of this clamping jaw ( 15 ) are arranged relative to the cutting element ( 41 ) can be moved elastically against the closing movement of the clamping jaws ( 15 , 16 ) to such an extent that the cutting edge ( 42 ) of the cutting element ( 41 ) projects beyond the clamping surfaces ( 38 ). 2. Instrument according to claim 1, characterized in that both the cutting element ( 41 ) and the clamping elements ( 37 ) are formed in one piece with the clamping jaw ( 15 ) and that the cutting element ( 41 ) is a rigid part of the clamping jaw ( 15 ), while the clamping elements ( 37 ) are connected to the remaining parts ( 34 ) of the clamping jaw ( 15 ) via elastically deformable regions ( 40 ). 3. Instrument according to claim 2, characterized in that the elastically deformable regions ( 40 ) are formed by elastically bendable webs of low height. 4. Instrument according to claim 1, characterized in that the clamping jaw ( 15 ) is designed in two parts with a rigid first part which comprises the cutting element ( 41 ) and the mounting of the clamping jaw ( 15 ) on the grasping instrument, and with a second part which comprises the clamping elements ( 37 ) and which is elastically movable on the first part. 5. Instrument according to claim 4, characterized in that the clamping elements ( 37 ) are elastically pivotably mounted on the first part. 6. Instrument according to claim 5, characterized in that the second part is U-shaped with two parallel legs forming the clamping elements ( 37 ) and a web ( 46 ) connecting them and closing the longitudinal slot ( 36 ) towards the distal end of the clamping jaw ( 15 ), and that the second part is rotatably mounted on the first part at the free ends of the legs. 7. Instrument according to one of the preceding claims, characterized in that the longitudinal slot ( 43 ) in the other clamping jaw ( 16 ), which has no cutting device, is closed at both ends.