WO2011018147A1

WO2011018147A1 - Tubular shaft of a surgical instrument

Info

Publication number: WO2011018147A1
Application number: PCT/EP2010/004385
Authority: WO
Inventors: Harald Hanke; Andreas Noack; Andreas Pohlmann; Hannes Miersch
Original assignee: Olympus Winter & Ibe Gmbh
Priority date: 2009-08-13
Filing date: 2010-07-19
Publication date: 2011-02-17
Also published as: DE102009037047A1

Abstract

The invention relates to a tubular shaft (1) of a surgical instrument, comprising at least one substantially flexurally rigid segment (3), at the distal end (6') of which a flexible area (4, 5) follows, wherein the shaft (1) is provided with an elongated tubular element (16) having segments (20, 120, 120') that can be longitudinally moved with respect to one another, wherein at the distal end (6') of the tubular element (16) the longitudinally movable segments (20, 120, 120') are fixed with respect to one another in the direction of the longitudinal axis. The tubular shaft (1) according to the invention is characterized in that a locking device (26, 32, 33) is provided, by way of which the position of the longitudinally movable segments (20, 20') to one another can be fixed.

Description

Tubular shaft of a surgical instrument Description

The invention relates to a tubular shaft of a surgical instrument with bendable areas. Such constructions are known from flexible endoscopes and also from endoscopic or laparoscopic instruments. As an example of a bendable endoscope shaft, EP 1 681 013 A1 is cited.

The bendable areas of such bendable Endoskopschäfte are steerable on complicated control devices and require a huge technical effort.

For simpler shanks of surgical instruments such. As for laparoscopic pliers such constructions are not suitable because of the high design complexity and the complicated operation.

However, there is an increasing need for shanks of surgical instruments for shanks that are simple and inexpensive. In some cases, the distal end regions can be adapted to the current work situation, or the collision problems can be reduced when working with several laparoscopic instruments through a single port.

It is an object of the present invention to make the surgical instrument known in the prior art, by means of which a controlled bendability is possible, safer in terms of operability.

This object is achieved by a tubular shaft of a surgical instrument having an at least substantially rigid portion, at the distal end of which a bendable region adjoins, wherein the shaft has a longitudinally extended rohrförmi- ges element having mutually longitudinally displaceable sections, wherein the longitudinally displaceable sections are fixed to the distal end of the tubular member longitudinally axial to each other, which is further developed by a locking device is provided by means of which the position of the longitudinally displaceable sections to each other can be fixed.

As a result, the degrees of freedom obtained by the degrees of freedom obtained in DE 10 2009 013 188 can be used in a simplified manner for the surgeon. It can namely instead of a fixation on, for example, a

Trocar, in order to have an abutment for the handle and the applied transverse forces and moments, if necessary, the bending of the bendable areas are fixed so that the surgeon in the usual way and easily perform its operation in this corresponding bent position of the shaft. Thus, the previous liberties of the surgeon, such as the movement in the axis of the trocar or a spatial rotation around the point of penetration of the trocar through, for example, an abdominal wall as well as mouth operation still available. By the measure according to the invention, the degrees of freedom of the spatial bending of the shaft end in the bendable region can be selectively and temporarily restricted. Through the locking device, a fixing mechanism is used, with which the spatial bending of the shaft can be released or prevented. Preferably, the shank has an outer tube which slidably receives the tubular element in its interior with close play. Preferably, the stem has an inner tube slidably disposed inside the tubular member with close clearance. In particular, preferably three tubular nested tubes are provided accordingly. Preferably, the longitudinally displaceable sections in the longitudinal axial direction tensile and pressure-resistant and otherwise preferably bendable. Preferably, the longitudinally displaceable portions are arranged longitudinally axially or substantially parallel to each other. Preferably, a bendable region adjoins the proximal end, wherein the longitudinally displaceable sections are fixed to the proximal end of the tubular element longitudinally axial to one another. As a result, a symmetrical configuration of the shaft is given. In particular, preferably, the locking device is self-locking. As a result, the bendable region can be actively moved by application of a force of the surgeon and automatically fixed upon completion of the movement. The fixation or locking remains in place until it is actively released again by operation. As a result, an additional element for fixing or locking and releasing is not required. Preferably, the self-locking is achieved by a gooseneck and / or a ball joint. In the case of the gooseneck, for example, the proximal control portion of the shaft, ie in particular, for example, the bendable portion of the proximal end portion 5 of the shaft, embedded in a gooseneck construction that maintains the mobility, but remains in the set orientation, due to the frictional forces or the material used in the gooseneck. The gooseneck can preferably be plugged separately.

0

In the embodiment of the self-locking effect by means of a ball joint, the surfaces adjoining each other in the ball joint can be frictional, in particular a force, friction and / or form-liquid connection can be provided in the ball joint. Die5 friction force can be adjusted for example by their spring force

Springs or produced by a different type tensioning element. The tensioning element may, for example, be a screw guided through a wall of the ball joint and pressing with a corresponding force against another wall of the ball joint. It can also be applied a hydraulic force.

Preferably, the locking device comprises a clamping element, which produces a clamping effect on the locking device and / or the 5 mutually longitudinally displaceable sections for fixing the longitudinally displaceable sections. Here, for example, a screw mechanism can be used, which or in which a conical screw thread is used or functionally a mechanism that has bendable sections as in a garden hose connector, are pressed by a nut against the shaft or a shaft tube, so that a locking of the tubes or the tubular element is achieved. Preferably, the locking device is arranged in a proximal region of the shaft. Preferably, the locking device is designed as a stiffening element arranged in the interior of the tubular element, by means of which a force can be acted on the longitudinally displaceable sections, or it comprises such a stiffening element. The stiffening element exerts a pressure on the longitudinally displaceable elements for locking the bending of the tubular shaft from the inside, by means of which they are locked.

Such a stiffening element is advantageously arranged in a proximal area and / or a middle area and / or a distal area of the tubular shaft. Thus, the stiffening can take place in a desired region of the tubular shaft. In particular, the locking in the distal end region has the advantage that external forces acting on the distal end region less lead to a bending, since the bend to

Locked in place, and not by force transmission to the proximal end portion.

Preferably, the stiffening element is formed by a bending of the tubular element between the longitudinally displaceable

Sections to be filled out. As a result, the effectiveness of the force and / or frictional determination is further increased. In an advantageous development, the stiffening element is designed to receive tensile forces exerted by a pull wire in the interior of the tubular element. The stiffening element ment can then serve as a guide for the pull wire, which is used for example for operating a mouth.

Preferably, the stiffening element by means of a pneumatic see, hydraulic, mechanical or electrical drive is designed to effect a frictional clamping of the longitudinally displaceable sections. An example of a pneumatically operated stiffening element is a rubber balloon, which can be acted upon by compressed air. In particular, rubber balloons with liquids for pressure transmission are used as hydraulic solutions

Question, in particular liquids are advantageously used, which are variable in their viscosity or their state of aggregation by external influences, such as pressure, temperature or electric fields. As mechanical systems, for example, parking brakes come into consideration, while

Piezoelectric elements allow electrical clamping or stiffening.

Preferably, a surgical instrument is provided with a shaft according to the invention.

According to the invention, a tubular shaft of a surgical instrument is provided with a rigid portion, at each of whose ends a bendable region adjoins, wherein at least the rigid portion and the two bendable portions are continuously passed by bendable, tension and compression-resistant rods, of which several are distributed over the circumference of the shaft, wherein the rods are longitudinally displaceable and mounted fixedly in the circumferential direction on the shaft and are fastened at the ends in each case on a parallel to the axis of the shaft guided tailpipe. In an embodiment according to the invention, the shaft has two bendable regions, which are passed through by rods arranged distributed over the circumference. If one bends one of the two bendable areas, one or more of these bars will be shortened in this area and others will be extended in this area.

The rods are circumferentially fixed and only longitudinally displaceable mounted on the shaft, so you can not dodge. You must transmit from the bending-actuated area resulting from shortening or extension of the area during bending movements by longitudinal displacement to the other bendable area. Since the rods are attached to the ends of axially parallel tailpipes and thus their length between the tailpipes is rigid and can not be corrected by lateral evasion, the rods have no choice but to shorten in the second bendable area or to lengthen that the second bendable portion is bent in a forced motion in a direction other than the bend-operated portion. This results in a shaft with two bendable areas and an intermediate rigid section. You can hold this shaft on the rigid section and bend at one of the bendable areas in any direction. It then forcibly bends the other area in the reverse bending direction. In this case, the ends of the two bendable regions are always parallel, so that the second bendable region can be controlled very simply and clearly by actuating the bending-actuated region. The technical effort to do so is extremely low. The shaft may be formed as a hollow tube, in which z. As surgical work channels, image guide, light guide, pull cable, electrical cables and the like can be laid. At one end of the shaft according to the invention, for example, a handle and at the other end a forceps jaw be arranged.

The construction of the invention is already functional with only three or four rods and can be very simple in this way. However, the rods must be stored multiple times and very precisely over their length in order to avoid lateral avoidance. Only then does the described forced bending result in a sufficiently precise manner. The preferred construction, in which the stem consists of three concentric and closely slidably intermeshing tubes, wherein the inner tube and the outer tube are rigid in the rigid portion and bendable in the bendable portions without substantial change in the circumferential length, and wherein the middle tube forms the tailpipes at its ends and is divided in the area between them with narrow longitudinal slots in slidably adjacent rods, it may be advantageous and in particular because of their lower technical complexity. In this construction, three tubes are inserted into each other, the z. B. are formed as thin metal tubes. The

Tubes are slidingly close together, so that the middle tube is protected by the inner and the outer tube against evasive movements inwardly or outwardly. The central tube forms the rods, preferably in large numbers in the circumference closely adjacent to each other, so that they support each other and prevent evasion in the circumferential direction.

Advantageous embodiments of the invention will become apparent from the other dependent claims. In this case, the middle tube is designed, for example, as a metal tube with longitudinal slots. Preferably, the inner tube and / or the outer tube are formed as metal tubes, which at the bendable areas with in longitudinal direction tion arranged in succession wide transverse slots are provided, which are alternately offset in the circumferential direction.

The invention is based on embodiments without limitation of the general inventive concept below

Reference is made to the drawings, with reference to all unspecified in the text details of the invention, reference is expressly made to the drawings. 1 is a schematic side view of a shaft according to the invention in a first embodiment,

Fig. 2 is a highly schematic enlarged section

Line 2-2 in Fig. 1 transverse to the axis of the shaft,

3 shows a view according to FIG. 1 through an embodiment variant of the first embodiment with a different bending characteristic, FIG. 4 shows a highly schematic section transversely to the axis of a shaft of a second embodiment,

5 is an enlarged perspective view of the detail V of FIG. 4,

6 is a side view of the outer tube of the construction of FIG. 4,

7 is a side view of the middle tube of the construction of FIG. 4, FIG.

Fig. 8 is a side view of the inner tube of the construction of Fig. 4,

9a is a schematic three-dimensional representation of an elongate tubular element,

9b shows a schematic three-dimensional representation of the elongate tubular element from FIG. 9a, in which the bendable sections or bendable areas are bent accordingly, FIG.

10 is a schematic representation of a locking device according to the invention,

1 is a schematic representation of a shaft according to the invention with a further locking device according to the invention,

Fig. 12 shows a further embodiment of an inventive

Shank with a further arresting device according to the invention and

Fig. 13 is a schematic representation of another shaft according to the invention with a locking device according to the invention.

FIG. 1 shows a first embodiment of a tubular shaft 1 according to the invention. The shaft is shown in section in FIG. 2 and, in the highly schematized representations of FIGS. 1 and 2, has a tube 2 which is rigid in a rigid section 3 is formed and is formed bendable in it at the ends subsequent bendable areas 4 and 5. At the bendable areas 4 and 5 can turn at the ends more areas begin, as in the example shown rigid end portions 6 and 6 '.

As shown in FIG. 2, the shaft 1 is traversed by four rods 7, 8, 9 and 10. Of these, only two, namely the rods 7 and 9, are shown in dashed lines in FIG. As shown in FIG. 2, the rods 7 - 10 are mounted in guides 1 1, which are fixed to the tube 2. The rods 7 - 10 are thus secured in the guides against lateral deflections, but can move longitudinally in the guides.

As shown in FIG. 1, the rods 7 and 9 thus always run parallel to the wall of the tube 2 through the bends in the bendable regions 4, 5. At the ends, the rods 7 - 10 are fastened to tail pipes 12, 12 'which are in Fig. 1 are also shown in dashed lines. The tail pipes 12, 12 'are guided axially parallel in the shaft 1 and indeed in

Embodiment in the rigid end regions 6 and 6 '.

In Fig. 1 of the four rods 7 - 10 for the sake of clarity, only the two rods 7 and 9 are shown. The construction of FIG. 1 and FIG. B. only three on the

Circumference distributed arranged rods have, or more than four.

Since the rods 7 - 10 are secured in the guides 11 against lateral Ausweich and since they are at the ends of the tailpipes

12, 12 'are fixed and their ends are thus always held on a plane transverse to the axis of the shaft 1, there is a forced movement, which will be explained below. If, as shown in FIG. 1, the bendable region 4 is bent in the direction of the arrow 13, the rod 9 shortens in this region 4, while the rod 7 must extend. Since the rods are longitudinally slidably mounted in the guides 11, the rods move accordingly in the rigid area 1. In the other two rods 8, 10, resulting in the case of bending as shown in FIG. 1, no shift.

5

Since the length of the rods 7, 9 between the tailpipes 12 is constant and lateral deflection is nowhere possible except for the second bendable region 5, this must bend in the direction shown in Fig. 1 in the direction of arrow 14, danno within the bendable area 5 extends the rods 9 and the rod 7 is shortened.

If the bending of the one bendable region 4 in the other direction, e.g. perpendicular to the plane of the drawing, the bendable region 5 bends in a corresponding manner perpendicular to the plane of the drawing.

As far as possible, the same reference numbers are used. In the section according to FIG. 2, the construction of FIG. 3 agrees with that of FIG.

It is only different in the construction of FIG. 3 that the rods 7, 9 run crosswise in the rigid section 3 of the shank 1. This is achieved in a simple manner in that they follow in this area, ie in the rigid section 3, the circumference of the tube 2 on a helix, which is predetermined by appropriate arrangement and design of the guides 11. o It turns out that when bending the bendable area 4 of the

3 in the direction of the arrow 13, ie in the same sense as in the illustration of FIG. 1, the second bendable Rich 5 in turn is bent forcibly, but in the opposite sense as in the construction of FIG. 5.

It is thus possible, according to the construction variants of FIGS. 1 and 3, to design shafts 1 in such a way that they bend in one direction when the one section is bent, and forcibly bend the other section either in one direction or the other. In the construction of FIG. 3, the rods 7, 9 are circumferentially offset in the rigid section 3 by 180 ° between the ends of this section. Would the Schraubenverwindung the rods 7 - 10 not over 180 °, but only about z. For example, when the region 4 of FIG. 3 moves in the manner shown, a movement of the other bendable region 5 upwards out of the plane of the drawing would result.

FIGS. 4 to 8 show a fundamentally different second embodiment of the shank 1, again using the previous reference numerals as far as possible. The shaft 1 is tubular in form of three closely fitted tubes, namely an outer tube 15, a middle tube 16 and an inner tube 17. FIG. 4 shows the interdigitation of these three tubes in a section perpendicular to the tube axis. A section V of the section of Fig. 4 is enlarged in Fig. 5 and shown in real, for illustrative simplification, however, without showing the pipe curvature. The tubes are shown in side view in Figs. 6-8.

The tubes 15, 16 and 17 are made in the embodiment of metal and z. B. cut with lasers in their special shape. FIG. FIG. 5 shows that the tubes 15, 16 and 17 are arranged very close to one another, ie as far as possible without a gap, so that the inner tube 17 and the outer tube 15 enclose the middle tube 16 closely between them. As material for the tubes 15, 16 and 17, for example, ferrous steel is suitable.

The outer tube 15 and the inner tube 17 are constructed very similar. When comparing with FIG. 1, they have the rigid section 3, to which the bendable regions 4 and 5 adjoin laterally, to which the rigid end sections 6 in turn connect.

In the exemplary embodiment, the bendable areas 4 and 5 are provided with transverse to the tube axis wide slots 18. These are also indicated in Fig. 4 with dashed areas of the tubes 15 and 17. The slots 18 are, as shown in FIGS. 6 and 8, arranged in the axial direction one behind the other alternately at 90 ° angularly offset and give a structure that is bendable in all directions, while always maintaining their circumferential length.

In an alternative, but less simple design, could also be used for the bendable areas a joint construction, as described in EP 1 681 013 A1. The central tube 16, the essential details of which are shown in Fig. 7 and in Fig. 5, is, as these figures show, provided at the ends with circumferentially closed end pipes 12 and 12 '. In the intermediate region, the tube 16 is longitudinally slotted with longitudinal slots 19, with which the tube in this area is subdivided into rods 20, which are close to each other on the very narrow longitudinal slots 19, as shown in Fig. 5 in the enlarged view , The rods are therefore supported laterally in the circumference close to each other and can not avoid pressure and tensile load, so are as safe against lateral deflection as the rods 7 - 10 in the construction of Fig. 1 and 2 in the guides 1 1.

In the embodiment of FIGS. 4-8, the shaft 1 reacts in flexion just as in the embodiment of FIG. 1. For this purpose, the three tubes 15, 16 and 17 must be pushed one above the other into a relative longitudinal position as defined by the superimposition. Arrangement of Fig. 6-8 results in the drawing. The middle tube

16 is thus with the tailpipes 12 in the rigid end portions 6 and 6 'of the inner and outer adjacent tubes 15 and 17. The tail pipes 12 and 12' are held by their leadership between the two tubes 15 and 17 parallel to the tube axis. The rods 20 of the middle tube 16 can not escape laterally due to their close abutment. Bending in this construction, one bendable region 4, the other bendable region 5 must follow with a forced bend, namely, as explained with reference to FIG. Also in the embodiment of FIGS. 4-8, the embodiment of FIG. 3 can be realized. For this purpose, the rods 20 of the central tube 16 in the rigid region 3, ie between the bendable regions 4 and 5 helically wound be formed. The shaft 1 according to the invention can be used as a shaft of a surgical

Instrument used. For example, it can form the shaft of an endoscope, wherein the interior of the tubular shaft 1, the facilities of an endoscope are laid, such. As image guide, light guide, working channel, electrical cables, etc. At one end, a window may be provided through which a lens looks, while at the other end are arranged manual control devices. Likewise, the shaft of the invention also as a shaft, z. B. a laparoscopic instrument, such. As a pair of pliers are used. Then at one end a handle and at the other end a forceps jaw is arranged. For required rotational actuations over the length of the shank z. B. in the embodiment of Figs. 4 - 8, the tubes 15 and 17 are rotated against each other, which is also possible in the bent state. Relative longitudinal displacements are also possible.

The rods 7 - 10 and 20 must be well slidably formed or arranged on all sides, so that there is a proper, precise forced bend in the shaft according to the invention. For this purpose, the rods, or the abutting surfaces, e.g. be polished, lubricated, coated or otherwise reduced friction.

Instead of the term "rods" used to date in the description, the term "longitudinally displaceable section" can also generally be used. In order to illustrate this, as a further embodiment according to FIGS. 9a and 9b, a tube 16 or an elongated tubular element 16 is shown, which preferably, like the elongate tubular element 16 or tube 16 from FIG. 7, is narrow between an outside Pipe 15 and an inner tube 17 may be plugged. The longitudinally displaceable portions 120 'and 120, which are shown in Figs. 9a and 9b, are mounted longitudinally displaceably at a gap 19. The longitudinally displaceable sections 120, 120 'pass over to the end pipes 12 and 12' by tapered sections 21, 21 '. As a result, an improved bendability of the bendable regions 4, 5 of the elongated tubular element 16 is given. By providing tapered sections 21, 21 'result in longitudinal axial apertures 22 to 25 in the bending region 4 and 5. In the figures, only two longitudinally displaceable sections 120, 120' are provided with reference numerals due to the three-dimensional schematic representation. However, there are two more longitudinally displaceable sections available.

In Fig. 9a, the tubular element 16 is shown in an undeflected or bent shape and in Fig. 9b in a deflected or bent shape. With regard to this embodiment of the tubular element 16 according to the invention, reference is made in particular to the patent application PCT / EP2009 / 051294 of 05.02.2009 or WO 2009/098244 A2. The further embodiments of the corresponding tubular elements as well as of the controllable tubes disclosed in this patent application (PCT / EP2009 / 051294) are to be incorporated in full in the disclosure content of this patent application.

The embodiments of the tubular shafts according to the invention have hitherto been formed substantially symmetrically. However, it is also possible to provide only at the distal end a bendable region 4 and at the proximal end instead of the bendable region 5 a control region, by means of which the corresponding desired movements on the längsverschiebba- ren sections can be generated.

Fig. 10 shows schematically a part of a shaft according to the invention with a locking device according to the invention. The locking device is designed in the form of a ball joint 26. The ball joint 26 has a guide tube 28 with a first

Half shell 29 'and a guide tube 28' with a second half-shell 29. The ball joint 26 encloses a bendable rich of the shaft 1, namely at the proximal end. 6

The ball joint 26 may be set self-locking. For this purpose, the contact surface 27 on the contact surface 27 'can be so firmly abutting that the friction of the contact surfaces is greater than that

Restoring force of the shaft. For this purpose, the inner half-shell 29 'have an outer diameter which is slightly larger than the inner diameter of the outer half-shell 29. The inner half-shell 29' and / or the outer half-shell 29 can then also be formed somewhat radially elastic.

Alternatively, for example, a clamping element 30 may be provided, for example, a spring load on the contact surface 27 'exerts or alternatively has a screw which presses on the contact surface 27'. The locking device in the form of the ball joint 26 can enable or prevent the bending of the shaft 1.

The ball joint 26 can be fixed by means of a lever as a trigger or push button or otherwise in its position or, accordingly, the fixation or locking can be solved to make a change in the angulation. Here are several variants possible. The joint can move freely until it is actively fixed. The fixation or locking remains in place until it is actively released again. This can be done for example by a push button or by twisting a screw. In addition, the joint can be permanently clamped or locked or locked with a spring loaded member to be released by active actuation. At the moment when the active operation ceases, the joint can be automatically locked again. Further, the lock can be tuned self-locking, for example, by a corresponding friction of the half-shells (29, 29 ') to each other and be aligned by clear actuation accordingly and remain in the respective position until a new significant force is exercised as movement. An additional element or clamping element 30 for locking or releasing is then no longer necessary.

FIG. 11 schematically shows a further embodiment of a shaft 1 according to the invention, in which the proximal end region 6 is embedded in a gooseneck 32. As a result, the mobility is maintained. The gooseneck ensures that the movable end area remains in the set orientation. The gooseneck, for example, be plugged separately or be releasably fixed to the bracket 31. The holder 31 may for example also be a trocar.

A further shaft according to the invention in a further embodiment is shown schematically in FIG. 12. In this case, the locking device 33 looks like a fixed part 34 with flexible

Elements 36 and a conical thread as indicated there is formed. A rotatable part 35 can be screwed onto the thread there and, by means of pressing elements 37 arranged on the rotatable part 35, exerts a radially inwardly acting force on the flexible elements 36, which exert a radial contact force on the shaft. As a result, the tubes or tubular elements are fixed relative to each other.

So that no remaining bending occurs, the inner tube is made sufficiently stable at least in this area or has a reinforcing element in this area. The inner sleeve or the inner tube, for example, in a length of 10 to 20 mm be strengthened.

The externally located radially acting clamping element may for example also be a collet, which is actuated, for example, with a clamping nut. The radially acting clamping forces increase the friction locally so strongly that a displacement of the central tube segment or of the longitudinally extended tubular element 16 is no longer possible or made correspondingly more difficult. This can also be provided for an overload protection.

FIG. 13 shows schematically another cross section of a further shaft 1 according to the invention with a locking device 42 according to the invention. The concentrically interlocking structures of the shaft 1 are from outside to inside an outer tube 15 as an outer guide tube, a central tube 16 as a control tube with longitudinally displaceable rods, not shown, and an inner tube 16 as an inner guide tube.

In the center of the shaft 1, a puller wire 40 is arranged, which is surrounded by a puller wire guard 41, for example a spiral. Between the puller wire guard 41 and the inner tube 17, a stiffening element 42 is arranged, which, in the activated state, exerts a pressure on the inner side of the inner tube 17 which acts in a radially outward direction, corresponding to the direction of force application 43 shown in FIG , This transmits this pressure on the rods of the central tube 16, whereby they are fixed.

The stiffening element is designed in the example of Fig. 13 as a balloon which is filled with compressed air or a hydraulic fluid. On the inside, it offers the puller wire (40) in the puller wire guard (41) a guide, so that in the event of any bending, the bend As soon as the stiffening element is activated, the length of the path of the puller wire 40 remains essentially unchanged. All mentioned features, including the drawings alone to be taken as well as individual features that are disclosed in combination with other features are considered alone and in combination as essential to the invention. Embodiments of the invention may be accomplished by individual features or a combination of several features.

LIST OF REFERENCE NUMERALS

1 shaft

3 middle section

4 bendable area

5 bendable area

6 proximal end region

6 'distal end region

7 - 10 pole

1 1 tour

12 proximal tailpipe

12 'distal tailpipe

15 outer tube

16 middle pipe

17 inner tube

18 slot

19 longitudinal slot

20 pole

21, 21 'tapered section

22 - 25 longitudinal axial aperture

26 ball joint

27, 27 'contact surface

28, 28 'guide tube

29, 29 'half shell

30 clamping element

31 bracket

32 gooseneck

33 locking device

34 fixed part

35 rotatable part

36 flexible element

37 pressing element pull wire

Zugdrahtschutz

stiffener

Direction of a force application longitudinally displaceable section

Claims

claims

1. tubular shaft (1) of a surgical instrument with an at least substantially rigid portion (3), at the distal end (6 '), a bendable region (4) connects, wherein the shaft (1) is a longitudinally extended rohrför- miges element (16) having mutually longitudinally displaceable portions (20, 120, 120 ^' ), wherein the longitudinally displaceable portions (20, 120, 120 ^' ) at the distal end (6 ') of the tubular member (16) are fixed longitudinally to each other, characterized in that a locking device (26, 32, 33, 42) is provided, by means of which the position of the longitudinally displaceable sections (20, 120, 120 ^' ) can be fixed relative to one another.

Second shaft (1) according to claim 1, characterized in that the shaft (1) has an outer tube (15) which receives the rohrför- mige element (16) in its interior with close play sliding.

3. shank (1) according to claim 1 or 2, characterized in that the shaft (1) has an inner tube (17) which is slidably disposed in the interior of the tubular member (16) with close clearance.

4. shank (1) according to one of claims 1 to 3, characterized in that the longitudinally displaceable sections (20, 120, 120 ') in the longitudinal axial direction tensile and are pressure-resistant.

5. shaft (1) according to one of claims 1 to 4, characterized in that at the proximal end (6) adjoins a bendable region (5), wherein the longitudinally displaceable portions (20, 120, 120 ') at the proximal end ( 6) of the tubular element (16) are fixed longitudinally to each other.

6. shaft (1) according to one of claims 1 to 5, characterized in that the locking device (26, 32, 33, 42) in a proximal region of the shaft (1) is arranged.

7. shank (1) according to one of claims 1 to 6, characterized in that the locking device (26, 32, 33, 42) is self-locking.

8. shaft (1) according to claim 7, characterized in that the self-locking by a gooseneck (32) and / or a ball joint (26) is achieved.

9. shank (1) according to one of claims 1 to 8, characterized in that the locking device (26, 32, 33, 42) comprises a clamping element (30, 36, 37), which is for fixing the longitudinally displaceable portions (20, 120, 120 ') produces a clamping effect on the locking device (26) and / or the mutually longitudinally displaceable portions (20, 120, 120').

5

10. Shaft (1) according to one of claims 1 to 9, characterized in that the locking device (26, 32, 33, 42) is designed as a stiffening element (42) arranged in the interior of the tubular element or a stiffening element ( 42), by means of which a force on the longitudinally displaceable portions (20, 120, 120 ') can be acted upon.

1. Shaft (1) according to claim 10, characterized in that the stiffening element (42) in a proximal region (6) and / or a central region (3) and / or a distal region (6 ') of the tubular element ( 1) is arranged.

12 shaft (1) according to claim 10 or 1 1, characterized gekennzeich-o net, that the stiffening element (42) is formed by a bending of the tubular element (1) between the longitudinally displaceable sections (20, 120, 120 ') resulting Fill in the column. 5

13. shank (1) according to any one of claims 10 to 12, characterized in that the stiffening element (42) is formed by a pull wire (40) in the interior of the tubular member (1) applied tensile forces. 0

14 shaft (1) according to any one of claims 10 to 13, characterized in that the stiffening element (42) by means of a pneumatic, hydraulic, mechanical or electrical is designed to drive a force-locking clamping of the longitudinally displaceable sections (20, 120, 120 ').

15. Surgical instrument with a shaft (1) according to one of claims 1 to 14.