CA2179807A1

CA2179807A1 - Flexible microsurgical instrument with rotatable clevis

Info

Publication number: CA2179807A1
Application number: CA002179807A
Authority: CA
Inventors: Matthew A. Palmer
Original assignee: Individual
Current assignee: Boston Scientific Miami Corp
Priority date: 1994-01-05
Filing date: 1995-01-04
Publication date: 1995-07-13
Also published as: JPH09507149A; DE69532711T2; JP3602535B2; EP0746242A4; WO1995018574A1; DE69535531T2; EP1325709A1; EP1325709B1; AU1448095A; DE69535531D1; US5439478A; DE69532711D1; EP0746242B1; EP0746242A1

Abstract

The instrument includes a flexible coil (14), a flexible pull wire (16) extending through the coil (14), a clevis (40) which is rotatably coupled to the distal end of the coil (14), a handle (12) coupled to the proximal end of the coil (14), and end effectors (18) coupled to the clevis (40) and the pull wire (16). The clevis (40) is coupled to the distal end of the flexible coil (14) by a bushing (60) which allows axial rotation of the clevis (40) relative to the coil (14). The pull wire (16) is formed from torsionally obdurate material and is coupled at its distal end to the end effector (18) and at its proximal end to a movable part of the handle (12). The handle (12) is provided with mechanism for rotating the pull wire (16) relative to the coil (14) and a mechanism for translating the pull wire (16) relative to the coil (14). Translation of the pull wire (16) relative to the coil (14) moves the end effector (18) relative to the clevis (40) and rotation of the pull wire (16) relative to the coil (14) rotates the clevis (40) and end effector (18) relative to the coil (14).

Description

W0 95/18574 ~ P~~
~ - 2 1 79807 A TI~ExIBLE ~-T. ,LhD llITII r lT~ TlTT~ CLEVID
TECHNICAL FIELD
miS invention relates to mi~;LUDUL~iCal i~ L_ .
More particularly, the present invention relates to micro-surgical iJ-,LL, having end e~uLu.D mounted on a clevis coupled to an actuation means by a flexible coil where the clevis is rotatable relative to the flexible coil.
Rb ~ ~uNl~ ART
Most mi-;Lul-uLyical il~DLL~ L~; used in laparoscopic and ~n~nccopir! ~uceluL~s include a pair of end effectors (cut-ters, dissectors, extractors, or the like) which are mounted on a clevis, where the clevis is coupled to the distal end of a tube. Proximal ends of the end effectors are often coupled to a push rod which extends through the tube. A
handle with an actuation means coupled to the proximal ends of the tube and the push rod is typically used to allow the practitioner to move the push rod relative to the tube, thereby opening and closing the end effectors. In some mi~:Lur~uLyical illDLL~ LD~ the tube and push rod are rigid members, ~uch as in parent application Serial Number 07/989,984. In other ill LL~ LS~ the "tube" is a long flexible coil and the "push rod" is one or more flexible wires such as in parent application Serial Number 08/042, 606 .
In,,LL ~ u~; 1; 7:;ng a rigid tube and push rod are typically relatively short and are i-lLL-~ lu~d into the body through a trocar tube. me practitioner views the surgical site through an optical device which is inserted in another trocar tube and "steers" the end effectors to the surgical site by angling the handle of the rigid in3LL, t, and thereby angling the entire illDLL L. Parent application 2 1 7 9 8 o 7 r~ n 1 .

Serial Number 07/989,984 llic~locPc means for rotating the end effectors by rotating the rigid tube relative to the handle. This permits the practitioner to adjust the rota-tional position of the end effectors without rhAn~n~ the rotational posltion of the handle.
utilizing a fleYihl~ coil and pull wire(s) are typically relatively long and are il.LLu-luued into the body through the narrow lumen of an ~ c vl,e . The practi-tioner views the surgical site through the ~n~ scope and inserts the long flexible coil of the ir.D~ through the narrow lumen of the -~ 6cul,e 80 th~t the end effectors eYtend beyond the distal end of the - l ~6~ ,l e. Since the fl~Y~hl-- coil cannot be steered, the practitioner 2iteers the end effe~ ~o- D to the surgical site by steering the endo-scope. me ~ S~cc ,l,e is typically relatively long and often follows a t~L Luuu6 path to the surgical site. Although the ~n~ ccr~re can be steered, its tortuous path makes it impos-sible to rotate. IIJ-~:ov_l, because the flexible coil of the surgical in,-- ~ is, by nature, torsionally r~c~ nt, any attempt to rotate the end ef~ectors by rotating the coil will at best result in a ~erk~ng .~ of the end e~fec-tors. At worst, the coil will deform without effecting any rotation of the end ef reuLuLD at all.
DISCrOSURE OF INVENTION
It is LL._.~:f6Le an object of the invention to provide a miL;-uDu-yical illD~L~ having a pair of distal end effec-tors coupled to a proximal handle by a flexible coil where the end effectors are rotatable.
It is also an object of the invention to provide a 30 miu,~,~-Lulcal illD~LI having a clevis ~ 4 at the distal end of a flf~y~hle coil where the clevis is rotatable relative to the coil .

~ W095/18574 - .;j; `~; I. 21 79807 }~ 'C

.
It is another object of the invention to provide a pull wire for co~lrl;n~ an end effector mounted at the distal end of a flexible coil to a proximal actuation means where the pull wire i8 torsionally rigid but otherwise fl~y~hl~-.
It is still another object of the invention to provide a handle for a miuLu~uL~lcal i~ LI L having a pair of distal end erre~.LcL~, coupled to the handle by a flexible coil and a pull wire where the handle is provided with manual means for rotating the end effectors.
It is still another object of the invention to provide a handle for a miuLu~uLyical in:iLL, ' having a pair of distal end ~:rr~uLoLD coupled to the handle by a t'l-~Y~hle coil and a pull wire where the handle is provided with means for rotating the pull wire relative to the coil.
In accord with these objects which will be rli~c~lR~ in detail below, the steerable fl~Yihle- miuL~,~.uL~ical instru-ment of the present invention broadly in~lt~ a fl~Y~hle coil, a handle coupled to the proximal end of the fl-~Yihle coil, a flexible but tnr~inn~-lly oLduL<.Le pull wire extend-ing through the flexible coil, a clevis which is rotatably coupled to the distal end of the coil, and at least one end effector mounted on the clevis. The clevis is coupled to the distal end of the fleYible coil by a bushing which allows rotation of the clevis relative to the coil about a longitudinal axis. The pull wire is formed from torsionally obdurate material and is coupled at its distal end to the end ~f~ctnr and at its proximal end to a movable part of the handle. The handle is provided with means for rotating the pull wire relative to the coil and means for translating the pull wire relative to the coil. Translation of the pull wire relative to the coil moves the end effector relative to the clevis and rotation of the pull wire relative to the Wo sS/18574 ~ I 2 1 7 9 8 0 7 r~

coil rotates the clevis and end ef fector rel_tive to the coil .
According to one: '; of the invention, the handle ; n~ a central shaft with a longitudinal slot about which a lliRrlAr!oAhle spool with a cross pin is dis-posed. The cQntral shaft has a thumb ring on its proximal end and longitudinal bore eYtending from its distal end into the distal end of the slot. The proximal end of the coil extends into the bore on the distal end of the central shaft and is held there by a bushing which allows the central shaft to rotate axially relative to the coil. The pull wire extends through the bore into the slot where it is coupled to the cross pin of the rl i ~pl~A~cPAhle spool . I,ongitudinal of the spool causes translational -- v~ L of the pull wire relative to the coil. Rotational ~ of the spool and central shaft causes rotation of the pull wire relative to the coil. A ~L~fe L~d aspect Or this: -tr L
iB to provide the thumb ring with a rotational joint 80 that the central shaft is rotatable relative to the thumb ring.
According to another: _ '1- L of the invention, a lever arm is pivotally engaged to the handle. The proximal end of the f 1 ~Yi hlP coil is f iYedly coupled to the handle and the proximal end of the pull wire is coupled to the lever arm by a rotational ~ member. The rotational e~ . L member is pre$erably a knurled disk where the pull wire is fixedly coupled to the disk, and the disk is rotationally coupled in a socket of the lever arm. At least a portion o$ the surface of the disk is exposed by the socket 80 that the disk may be rotated by the practitioner's finger or thumb.
In either of these two: -'; , a variety of dif-ferent end effectors may be used including cutters, grip-pers, forceps and the like. The end ~rr.,. ~r,r_ may be single ~ WO95/1857~ 2 1 79807 .~~ C 1 acting or double acting and may be coupled to the handle via a single pull wire or multiple pull wires.
Preferred aspects of the rotatable clevis a include providing the clevis bushing with a stepped inner 5 ~i ~ Pr and providing the clevis with a cylindrical stem.
The cylindrical stem of the clevis is fitted into the small-er inner rl~i ' Qr portion of the clevis bushing and flared at its proximal end to attach the clevis to the bushing.
The larger inner fli~ ~ or portion of the clevis bushing is 10 fiYed to the distal end of the coil by crimping, welding or soldering. The rotational co~rl ~ng of the clevis and the clevis bushing may be DnhAnr~l by the use of friction reduc-ing bearings (e.g. ball bearings or needle bearings) between the clevis stem and the smaller inner ~ r portion of 15 the clevis bushing. Alternatively, the clevis stem and/or the smaller inner ~li ' portion of the clevis bushing may be coated wit.h TBFLON or provided with a TEFLON sleeve.
Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference 20 to the /l~tAil~d description taken in ~u~.ju~.vLion with the provided f igures .
8RIEF DES~ OF nD~
Figure 1 is a side elevation view in partial longitudi-nal section of a first ~ L of the proximal end of the 25 mi~;LVDULyiCal ir.~LL, ' of the invention;
Figure 2 is a side elevation view in partial longitudi-nal section of a second ~ ' of the proximal end of the miv,~ uLyical in.iLL t of the invention;
Figure 3 is a side elevation view in partial longitudi-30 nal section of the distal end of a first: ' -'i ' of the mi~ ,u,yical i~ LL, L of the invention;

W095ll8574 j . 21 798 ~7 r Figure 4 i8 a top view o~ the clcvi5 assembly and coil o~ Pigure 3;
Figure 5 is an exploded top view of the clevis assembly and coil o~ Figure 4;
Figure 6 i6 an enlarged top view of a second of the clevis assembly;
Figure 7 is an enlarged top view o~ another ~ L
of the clevis bushing;
Figure ~8 is a cross Sorf i o~ view along line 8-8 of lo Figure 7;
Figure 9 is an enlarged top view of another ~ t of the clevis assembly;
Figure 10 is an enlarged top view o~ another o~ the clevis;
Figure 11 is a cross sectional ViQW along line 11-11 of Figure 10:
Figure 12 is a view sim1 lar to Figure 3 showing a double acting biopsy forceps according to a second e~bodi-ment o~ the invention;
Figure 13 is an enlarged side elevation view of a ~irst alternate . ' '; t of pull wires for use with a double acting end efrector;
Figure 14 is an enlarged side elevation view of a second alternate: ' '~ ' o~ pull wires for use with a single acting end ef fector;
Figure 15 is a side elevation view in partial longitu-dinal section of another ~ ' --t t. of the mic.:L~uLylcal il-aLL, L of the invention; and Figure 16 is a top view of a portion of the lever arm o~ Figure 15 showing the rot~t;nn~l L.l,_, L o~ the pull wire with t.he lever arm.

~ W0 95/18574 ` ' `- 2 t 7 9 ~ 0 7 r~

BEST MODE FOR CARRYING OUT THE INVENTION
A rirst: 'i of the mi~Lv;,uL~ical in;,L., 10 of the invention is shown in Figures 1 and 3. The instru-ment 10 i n~ w a proximal handle 12, a f lexible member 14 5 such as a coil which is coupled at its proximal end to the handle 12, a flexible pull wire 16 which extends through the flexible memher or coil 14, distal end e~r~vLoL:. ~8 which are coupled to the distal end of the pull wire 16, and a rotatable clevis assembly 20 which is coupled to the distal 10 end of the coil 14.
The proximal handle 12 of the in.-LL. L 10 has a central shaft 22 and a ~ i wrl Ar~C Ahle spool 24 . A thumb ring 26 is optionally rotatably coupled to the proximal end 27 of the central shaft 22 and a longitudinal bore 28 is provided 15 at the distal end of the shaft 22. A longitudinal slot 30 extends from the proximal end of bore 28 to a point distal of the thumb ring 26. The rliwrl~eAhle spool 24 is provided with a cross pin 32 which passes through the slot 30 in the central shaft 22. The cross pin 32 is provided with a set 20 screw 34 for ~n~A,~i n~ the proximal end of the pull wire 16 .
In accord with a ~reLL-ad aspect of the invention, the proximal end of the coil 14 is mounted in a stepped longitu-dinal bore 28 so that the central shaft 22 is axially rotat-able relative to the coil 14 . According to a f irst embodi-25 ment as seen in Figure 1, rotational ing is preferablyobtained by providing a bushing 35a which is mounted in a recess 36a in the bore 28 and which receives the proximal end of the coil 14. The bushing 35a is provided as a frus-trocnn;--~l member 37a which is r~W~ ontly deformed as it is 30 pushed into the distal end of the bore 28, and which expands into the recess 36a and isi held therein. Of course, if desired, instead of providing a r~w~ nt ~LuDL~v~ ,.i member 37a, the central shaft 22 may be formed as a two WO95/18~74 ~ ; s j ~ 2 1 798 07 t~-,, s ~ ~

piece unit, and snapped t~qeth~, or otherwise joined around the coil 14 and bushing 35a. Alternatively, and as seen in Figure 2, a cylindrical body 35b i8 fixedly mounted at the proximal end of the coil 14 and a sleeve 37b is located 5 distally of the body 35b . The outer ti i ~ ~- o~ the cylin-drical body 35b is larger than the inner diameter of the sleeve 37b. The sleeve 37b is fixedly mounted in the bore 28 by gluing, sonic welding, or the like. The coil 14 i8 free to rotate within the sleeve 37b and the cylindrical 10 body is free to rotate within the bore 28. The coil 14 is, ntv~=LLl.eless, coupled to the shaft 22 because the cylindri-cal body 35b PL-..-I~LS the coil 14 ~rom being removed rrom the sleeve 37b. Regardless, from the foregoing, those skilled in the art will appreciate that rotation of the central shaft 22 relative to the coil 14 results in a corre-~rnnrlin~ rotation of the tli~D]arr~hle spool 24 and vice versa because of the ell,_, L of the cross pin 32 and the longitudinal slot 30. I~L~OV~=I, rotation o~ the centr~l shaft 22 or the tiicpl~cr~hle spool 24 relative to the coil 14 results in a rotation of the pull wire 16 relative to the coil 14 because the pull wire 16 i5 fixed ln the spool 24.
In accord with the pre~erred 'i-- o~ the invention, the f~ Yihle pull wire 16 is formed as a torsionally rigid member, pre~erably from drawn, round, stralghtened 304V
(vacuum melted) sf~-;nlr~ steel.
Turning now to Figures 3, 4, and 5, it is seen that the distal end of the coil 14 is coupled to the rotatable clevis assembly 20 . The clevis assembly 20 i n~ a clevis 40 and a clevis bushing 60. Clevis 40 has a pair of clevis arms 42, 44, each of which is provided with an aYle hole 46, 48 ~or receiving a clevis axle 50 upon which the end effec-tor6 18 are mounted in a conv~ntir~n~l manner. A cylindricAl stem 52 with a throughbore 54 is provided at the proximal ~ WO95/18574 i ~ 2 ~ 798(~7 r ~,~j ;. 1 g end of the clevis 40 . The t~lLvuyl-bOL~ 54 ~ i ~Ates with the space between the clevis arms 42, 44 and receives the distal end of the pull wire 16 as seen best in Figure 3.
The clevis bushing 60 is provided with a stepped Lhlvu~lL~vvLa 62, 64. In particular, the proximal portion 62 of the thl UUylLVUL ~ has a larger inner diameter than the distal portion 64 of the throughbore, thus creating an annular step 63 in a central part of the bushing 60. The inner r~ ' or of the distal portion 64 of the bushing Lll~ UU~I~UL~ is sized to receive the cylindrical stem 52 of the clevis 40. Ac-cording to a ~Lef~LLe:d: ' ~'i- L, the cylindrical stem 52 of the clevis 40 and the distal portion 64 of the bushing throughbore are also sized such that the proximal end 53 of the stem 52 extends beyond the annular step 63 when the clevis and bushing are ~ nn~ct~d as shown in Figures 3 ~nd 4. Further, according to the l . ~r~L.ed . - ~1 , the proximal end 53 Qf the cylindrical stem 52 is flared after the clevis and bushing are conn~ctecl 80 that the clevis stem is held rotatably within the bushing. The flaring may be A~ Rh~(l by inserting a conical tool into the proximal end 53 of the cylindrical stem 52 or by other te~lhn~T~
Regardless, after the clevis and clevis bushing are 80 l ~ri, the proximal portion 62 of the throughbore of the clevis bushing 60 is attached to the distal end of the coil 14 by crimping, welding or soldering.
Turning now to Figures 6 through 8, according to the invention, some type of friction reducing means preferably is provided between the clevis 40 and the clevis bushing 60.
Figure 6 shows a TEFI~ON sleeve 59 which has an inner diame-ter slightly larger than the outer r'iii "-r of the cylindri-cal stem 52 of the clevis 40 and an outer ~ r slightly smaller than the inner ~ ~r of the distal portion 64 of the clevis bushing throughbore. The length of the sleeve 59 WO9S/18574 ' - I '; 2 ~ 79807 P~IIIJ~.,~ ~ 1 ~

is slightly shorter than the length of the distal portion 64 of the clevis bushing U-Luu~l~ore. Those skilled in the art will thus appreciate that the TEFLON sleeve 59 i5 ~ inn-ed to fit over the cylindrical stem 52 of the clevis 40 5 before the clevis is attached to the clevis bushing and to thereby provide a lubricious lnterface between the clevis and the clevis bushing to f~A~il 1tAte their rotational en-~ ~, L ~ .
Figures 7 and 8 show an alternate ~ of a clevis bushing 160 having a stepped thLuu~l.bore 162, 164 where the proximal portion 162 of the Lllruu~l~uLe has a larger inner diameter than the distal portion 164 of the tllruuyl.bore, thus creating an annular step 163 in a ce~tral part of the bushing 160. According to this ~ , the distal portion 164 of the clevis bushing U1LO~I~UI~ i5 formed as a race containing a nu~ber of radially ~ pos~
roller bearings 165. When the clevis 40 is u~ 1 to the clevis bushing 160, the cylindrical stem 52 o~ the clevls is engaged by the roller bearings 165 thereby ~nhAnrin~ the rotational el ,_, L of the clevis and the clevis bushing.
Figure 9 shows an alternate ` '; L of a rotatable clevis assembly 220 . The clevis assembly 220 i nrl~ a clevis 240 and a clevis bushing 260. Clevis 240 has a pair of clevis arms 242, 244, each of which is provided with an axle hole 246, 248 ~or receiving a clevis axle 50 (Figures 4 and 5) upon which the end e~reuLuL:. are mounted in a conven-tional manner. A UlLvuyl~buIe 264 having a distal annular step 264a ; c~tes with the space between the clevis arms 242, 244 and provides passage for the pull wire. The clevis bushing 260 is provided with a stepped thLuuyl.bure 262, 254. In particular, the proYimal portion 262 of the UILuu~LbuLe has a larger inner tl;~ ' than the distal portion 254 of the th~u~l buL~, thus creating an annular W095/18574 ~ , 2 1 7 9 8 û7 step 263 in a central part of the bushing 260. A cylindri-cal stem 252 is provided at the distal end of the bushing 260. The inner diameter of the clevis throughbore 264 is sized to receive the cylindrical stem 252 of the bushing 260. Preferably, the cylindrical stem 252 of the bushing 260 and the clevis ~ILv~ bv~ a 264 are also sized such that the distal end 253 of the stem 252 extends beyond the annu-lar step 264a when the clevis and bushing are cnnnect~d.
Further, the distal end 253 of the cylindrical stem 252 is flared after the clevis and bushing are connected so that the bushing stem is held rotatably within the clevis VU~hbV.~e. The flaring may be accomplished by inserting a conical tool into the space between the clevis arms 242, 244 or by other t~ hn;~ . Regardless, after the clevis and clevis bushing are 50 s~r- led, the proximal portion 262 of the th~vuyl~bvle of the clevis bushing 260 is attached to the distal end of the coil or ~ Y;h1 P member 14 by crimping, welding or soldering.
As described above with r ere. ence to Figures 6 - 8, some type of friction reducing means preferably is provided between the clevis 240 and the clevis bushing 260. Figure 9 shows a TEFLvN sleeve 59 which has an inner diameter slight-ly larger than the outer ~ of the cylindrical stem 252 of the bushing 240 and an outer rli; ~.r 81ightly small-er than the inner rl; t,~r of the clevis throughbore 264.
The length of the sleeve 59 is slightly shorter than the length of the clevis ~1l vu~l~v~ê. Those skilled in the art will thus appreciate that the TEFLON 81eeve 59 is rl ~ nn-ed to fit over the cylindrical stem 252 of bushing 260 before the clevis is attached to the clevis bushing and to thereby provide a lubricious interface between the clevis and the clevis bushing to facilitate their rotational en-W0 9511857~ 2 1 7 9 8 ~ 7 ~ ? ~ ~

Figures 10 and 11 show an alternate: - ' i t of a clevis 340 having a stepped throughbore 364, 364a. Accord-ing to this ~ --ir ~, the proximal portion of the LhL~
bore 364 is formed as a race containing a number of radially ,~ ros~ roller bearings 365. When the clevis 340 is con-nected to the clevis bushing 260, the cylindrical stem 252 of the bushing 260 is engaged by the roller bearings 365 thereby ~nhAn~ in~ the rotational ~n~n; of the clevis and the clevis bushing.
Returning to Fig. 3, it is seen that the end effectors - 18 in the: 'i t of Figure 3 comprise a single acting scissors having a stationary cutting blade 70 and a movable cutting blade 72. Both of the blades 70 and 72 are mounted between the clevis arms 42, 44 in a conv~ntit~n~l manner.
The proximal end of the movable cutting blade 72 is provided with a tang 74 having a hole 76 for at1~ L to the distal end of the pull wire 16. As described more fully in parent application Serial ~umber 08/042,606, the pull wire 16 is typically provided with a "jogged" distal end which engages the hole 76 in the tang 74 of the movable cutting blade 72.
Referring now to Figures 1 and 3, those skilled in the art will appreciate that translational ~ ~. L of the spool 24 relative to the central shaft 22 on the handle 12 in the directions indicated by the arrows "0", will result in a translational - . c L of the pull wire 16 relative to the coil 14. This in turn results in a ~ L of the movable cutting blade 72 about the clevis axle 50 in the directions indicated by the arrows "P" to thereby effect a cutting action between the blades 70, 72 . I~L C~V-C1~ in accord with the invention, it will be appreciated from the foregoing description that rotation of the central shaft 22 and the spool 24 relative to the coil 14 in the directions i n~ d by the arrows "Q" will result in a rotation of the pull wire W0 9Sl18574 2 t 7 9 8 0 7 P~

16 relative to the coil 14 as shown by the arrows "R". This results in a rotation of the clevis 40 (240, 340) relative to the clevis bushing 60 (160, 260) in the directions indi-cated by the arrows "S". It will also be appreciated that such a rotation of the clevis 40 (240, 340) relative to the clevis bushing 60 (160, 260) results in a rotation of the end effectors 18 relative to the coil 14.
In order to operate the illDLLI l. Or the invention, the practitioner inserts a thumb through the thumb ring 26 of the handle 12 and grasps the spool 24 between the index and middle finger. Translational .~ ~ of the pull wire is effected by sq -~7in~ the thumb ring and spool like a llyl~o~ needle. The preferred rotational co~rl in~ of the thumb ring 26 with the central shaft 22 allows the practi-tioner to rotate the spool without removing the thu~b from the thumb ring. Alternatively, the practitioner may hold the thumb ring 26 in the palm of the hand with the middle, fourth and fifth fingers, while the thumb and index finger are used to rotate the spool 24.
As mentioned above, the present invention is not lim-ited to use with any particular type of end effectors. As shown in Figure 12, for example, a double acting biopsy forceps including a pair of jaws 80, 82 may be provided on the clevis 40. When double acting end effectors are used, an additional pull wire 17, preferably attached to pull wire 16, may be provided within the coil 14. Alternatively, a single pull wire may be used And split into two courl i n~
~1 or aLI ~ d to a Y-adapter which are known in the art .
An alter~late -'i-- ( of the pull wires 16, 17 is shown in Figure 13 where a pair of f ~1: ' 116 and 117 are soldered or welded tc,ycrl 1 at their proximal ends 116a, 117a and twisted to form a single pull wire having a pair of Wo 9511~574 wound f i l - . The separate distal ends 116b, 117b of the f; 1; L5 are respectively coupled to the tangs of double acting end effectors. Those skilled in the art will appre-ciate that this ~ L of a pull wire having wound f 11~ ' has the characteristic that it is torsionally obdur~te in one direction only. For eYa~ple, zls shown in Figure 13, the wound f; 1: ~5 116, 117 are held tightly together when their proximal ends 116a, 117a rotated in the direction "T" and isuch rotation will result in a CjULLe~
ing rotation at their distal ends 116b, 117b. Rotation of the proximal ends of the wound f i l i in an opposite direction, however, will unwind the f;l~ ' prior to effecting any rotation at their distal ends.
It will be appreciated, that if desired, the "one-way"
rotation characteristic obtained by the twisted pull wire of Fig. 13 can be used in conjunction with a single acting end effector. Alterniatively, and as shown in Figure 14, a two fil~ ~ 216, 217 pull wire similar to the pull wire shown in Figure 13 can be used where the proximal ends 216a, 217a of the ~ s are soldered or welded and the distal ends 216b, 217b of the fil~ are also sol-dered or welded. It will be appreciated that with a single acting end erfec~oL, the distal ends 216b, 217b are soldered or welded as there is no need to provide two col~rl 1 n~ ends of the pull wire.
Another i 80 of the mi_..DuL~ical illDLL
is seen in Figures 15 and 16 and; nrl ~ a flexible coil 14, a flexible pull wire 16 extending through the coil 14, distal end e~e i~uLD 18 coupled to the pull wire 16, a 30 rotatable clevis assembly 20 which is coupled to the distal end of tbie coil 14, and a proximal actuation assembly 82.
In this: ir ' ~ the proximal actuation assembly 82 has a stationary handle portion 84 which is provided with f ~nger ~ W0 95118574 ~ 2 1 7 q 8 0 7 F~~

Lccesses 86, two of which are covered by a finger ring 85, and a throughbore 88 for receiving the coil 14 and pull wire 16. A lever arm 90 having a thumb ring 92 is pivotally attached to the stationary handle 84 by a pivot axle 94.
5 The lever arm 90 has a bore 96 which is substantially coax-ial with the bore 88 in the stationary handle and a slot 98 which is DUL~ .l ;A1 1Y or~hngonAl to the bore 96. The slot 98 is fitted with a knurled disk 100 having a pull wire receiving bore 102 and a set screw 104.
The proximal end of the coil 14 is mounted within the ,u~llbuLc 88 of the stationary handle 84 by crimping, soldering, ~. ,DULC fit or other suitable method. The proximal end of the pull wire 16 is inserted into the bore 102 of the disk 100 and held in place by the set screw 104.
Those skilled in the art will appreciate that the pull wire 16 is therefore rotatable relative to the actuation assembly 82 by rotation of the knurled disk 100 inside the slot 98 in the lever arm 90 . It will also be appreciated that -of the lever arm 90 relative to the stationary handle 84 will cause a translational - .c of the pull wire rela-tive to the coil to open and close the end ~ff~ctnrs 18. It will further be appreciated that, while the coil 14 and pull wire 16 are preferably flexible, a more rigid tube and rod such as are described in the previously refe~ ed Serial No. 07/989, 984 may be used in lieu thereof . When a more rigid control member is used in place of pull wire 16, the cOurl; n~ to the knurled disk at the proximal end is p~cfeL
bly AC ~ h~-~ by a ball and socket ~L a,ll~ ' .
In operation, the practitioner holds the actuation assembly 82 with fingers wrapped around the l~C"'~ 86 and with the thumb inserted in the thumb ring 9 2 . The index finger is free to rotate the disk 100 which effects a rota-tion of the pull wire 16 and thus a rotation of the clevis W095/18574 ;~ i ~ 2 ~ 79807 ~ C~ , ~

40 and end effectors 18 as described above with Lt f~L~I Ce to the first ' ~'; L of the invention.
There have been described and illustrated herein sev-eral -~i of a steerable floY;hle mic; .~n~lL~ical 5 innLL L with a rotatable clevis. While particular em-bo-l; of the invention have been described, it is not ;nton~od that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the ~reclflcation be read likewise.
10 Thus, while particular end erLe~Lu~n have been fl;~closecl, it will be appreciated that other single acting or double acting end offectors could be utilized. Also, while partic-ular handle CILL~ - have been shown, it will be recog-nized that other types of handles could be used with similar 15 results obtained. rIJLe:~ve:l, while particular con~igurations have been l; ~clof:o~ in reference to the clevis and the clevis bushing, it will be appreciated that other con~igura-tions could be used as well. Further, while the invention was described as having a clevis which is rotatable relative 20 to the coil, it should be appreciated that some rotation of the coil might occur upon rotation of the clevis and the end effectors due to friction. Such rotation of the coil, however, is ;n~ ~e~l Lial, as it is actually the rotation of the end offectors relative to the ~ cvl,e which is 25 desired and which is ~ hod by the invention. It will therefore be appreciated by those skilled in the art that yet other - - '; f; I-~tions could be made to the provided inven-tion without deviating from its spirit and scope as so clai_d.

Claims

1. A surgical instrument, comprising:
a) a flexible member (14) having a proximal end and a distal end;
b) a flexible but torsionally obdurate pull wire (16) having a proximal end and a distal end and extending through said flexible member (14);
c) an actuation means coupled to said proximal ends of said flexible member (14) and pull wire (16) for effecting a translational movement of said pull wire (16) relative to said flexible member (14), said actuation means including rotation means for effecfing a rotation of said pull wire (16) relative to said flexible member (14);
d) a clevis (40) rotatably coupled to said distal end of said flexible member (14); and e) at least one end effector (18) coupled to said clevis (40) and coupled to said distal end of said pull wire (16), wherein rotation of said pull wire (16) relative to said flexible member (14) effects a rotation of said clevis (40) relative to said flexible member (14).

2. A surgical instrument according to claim 1, further comprising:
f) a bushing (60) coupled to said distal end of said flexible member (14) and to said clevis (40).

3. A surgical instrument according to claim 2, wherein:
said bushing (60) is a cylinder with a stepped inner diameter and said clevis (40) has a cylindrical stem (52).

4. A surgical instrument according to claim 3, wherein:
a larger inner diameter portion of said bushing (60) covers said distal end of said flexible member (14) and said cylindrical stem (52) enters a smaller inner diameter por-tion of said bushing (60).

5. A surgical instrument according to claim 4, wherein:
a proximal end of said cylindrical stem (52) is flared.

6. A surgical instrument according to claim 2, wherein:
said clevis (40) has a throughbore (54) with a stepped inner diameter and said bushing (60) has a cylindrical stem (52) .

7. A surgical instrument according to claim 6, wherein:
said cylindrical stem (52) enters said trhoughbore (54) of said clevis (40).

8. A surgical instrument according to claim 7, wherein:
a distal end of said cylindrical stem (52) is flared.

9. A surgical instrument according to claim 1, wherein:
said actuation means comprises a slotted shaft (22) and a displaceable spool (24), said proximal end of said flexi-ble member (14) being coupled to said shaft (22) and said proximal end of said pull wire (16) being coupled to said spool (24).

10. A microsugical instrument according to claim 9, where-in:
said proximal end of said flexible member (14) is coupled to said shaft (22) with a bushing (60) and said shaft (22) is provided with a rotatable proximal thumb ring.

11. A surgical instrument according to claim 1, wherein:
said actuation means comprises a handle (12) and a lever arm (90), said proximal end of said flexible member (14) being coupled to said handle (12) and said proximal end of said pull wire (16) being coupled to said lever arm (90).

12. A surgical instrument according to claim 11, wherein:
said lever arm (90) is provided with a disk (100) receiving slot, said rotation means comprises a knurled disk (100) and said proximal end of said pull wire (16) is cou-pled to said knurled disk (100) so that rotation of said knurled disk (100) rotates said proximal end of said pull wire (16).

13. A surgical instrument according to claim 12, wherein:
said knurled disk (100) has a first bore ror receiving said proximal end of said pull wire (16), a set screw (104), and a second bore intersecting said first bore and contain-ing said set screw (104) which secures said proximal end of said pull wire (16) in said first radial bore.

14. A surgical instrument according to claim 2, further comprising:
g) friction reducing means for reducing friction between said bushing (60) and said clevis (40).

15. A Durgical instrument according to claim 14, wherein:
said friction reducing means is a TEFLON sleeve (59) located between said bushing (60) and said clevis (40).

16. A surgical instrument according to claim 14, wherein:
said friction reducing means comprises a plurality of roller bearings (165) located in one of said bushing (60) and said clevis (40).

17. A surgical instrument according to claim 1, wherein:
said pull wire (16) is formed from a pair of wound filaments and is torsionally obdurate in one direction only.

18. A surgical instrument according to claim 1, wherein:
said at least one end effector (18) comprises a pair of biopsy forceps jaws.

19. A clevis assembly for use in a surgical instrument having an end effector, said clevis assembly comprising:
a) a clevic member (240) having a base, a first arm (242), and a second arm (244), said first and second arms (242, 244) defining an end effector mounting space between said first and second clevis arms (242, 244), said first and second clevis arms (242, 244) being joined together at said base, said clevic member (240) further having a throughbore (264) in said base communicating with said end effector mounting space; and b) a clevis bushing (260) having a throughbore (264) with a stepped inner diameter with a smaller diameter portion and a larger diameter portion, wherein a first one of said clevic member (240) and said clevis bushing (260) has a cylindrical stem (252) extending into the throughbore (264) of a second one of said clevic member (240) and said clevis bushing (260), wherein said clevic member (240) rotates relative to said clevis bushing (260).

20. A clevis assembly according to claim 19, wherein:
said cylindrical stem (252) has a flared end.

21. A clevis assembly according to claim 19, wherein:
said cylindrical stem (252) is covered with a friction reducing material.

22. A clevis assembly according to claim 19, further com-prising:
c) bearing means disposed between said cylindrical stem (252) and said second one of said clevic member (240) and said clevis bushing (260) for reducing friction between said cylindrical stem (252) and said second one of said clevic member (240) and said clevis bushing (260) as said clevic member (240) rotates relative to said clevis bushing (260).

23. A surgical instrument, comprising:
a) a tube member having a proximal end and a distal end;
b) a torsionally obdurate control member having a proximal end and a distal end and extending through said tube member;
c) an actuation means coupled to said proximal end of said tube member and to said proximal end of said control member for effecting a translational movement of said control member relative to said tube member, said actuation means including rotation means for effecting an axial rotation of said control member relative to said tube member;
d) a clevis (40) rotatably coupled to said distal end of said tube member; and e) at least one end effector (18) coupled to said clevis (40) and coupled to said distal end of said control member, wherein axial rotation of said control member relative to said tube member effects an axial rotation of said clevis (40) relative to said tube member.