US3613662A

US3613662A - Cold conization instrument

Info

Publication number: US3613662A
Application number: US15192A
Authority: US
Inventors: Stavro A Chrysostomides
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-02-27
Filing date: 1970-02-27
Publication date: 1971-10-19
Anticipated expiration: 1988-10-19

Abstract

A medical instrument for removal of a conical section of tissue from the cervical is including the endocervical canal for obtaining a biopsy specimen in a procedure known as cold conization. The instrument utilizes a pistol grip on the body portion and a pneumatic air motor for reciprocal movement of a pair of coacting arcuate blades which may be rotated about the longitudinal centerline of the instrument and are positioned to remove a uniform conical biopsy section.

Description

United States Patent Appl. No.

Stavro A. Chrysostomides Rt. 1, Box 124, Columbia, S.C. 29403 15,192

Feb. 27, 1970 Oct. 1 9, 197 1 Inventor Filed Patented COLD CONIZATION INSTRUMENT 10 Claims, 13 Drawing Figs.

U.S.'Cl 128/2 B, 30/272, 30/273, 128/305, 128/311 Int. Cl ..A6lb 10/00,

A61b 17/32, B26b 07/00, E2lb 0 1/0 2 F15b 13/04, FOld 15/06 Field of Search 128/2 B, 2

References Cited UNITED STATES PATENTS 2,168,703 8/1939 Dziedzic et al. 30/272 2,596,078 5/1952 Prohaska 30/316 2,827,039 3/1958 Sieger 128/2 3,023,563 3/1962 Tenney 56/265 3,221,406 12/1965 Knoll 30/272 Primary Examiner-Aldrich F. Medbery Attorney-C. Gordon McBride ABSTRACT: A medical instrument for removal of a conical section of tissue from the cervical is including the endocervical canal for obtaining a biopsy specimen in a procedure known as cold conization. The instrument utilizes a pistol grip on the body portion and a pneumatic air motor for reciprocal movement of a pair of coacting arcuate blades which may be rotated about the longitudinal centerline of the instrument and are positioned to remove a uniform conical biopsy sectron.

3,613.662 PATENTEUum 19 I9?! SHEEI 2 0F 5 I N VENTOR.

STAV 8. CHRYSOSTOMIDES PATENTEDUCT 191971 sum 30F 5 FIG. ll

{g g/ 202 4 206 Q FIG.7

INVENTOR.

STAVRO S. CHRYSOSTOMIDES M z/A f PATENTEDHBT 1 9 I97! SHEEI u 0F 5 FIG. IO

INVENTOR.

STAVRO S. CHRYSOSTOMIDES PATENTEDUET 19197! 3, 13,552 SHEET 5 OF 5 INVENTOR.

STAVli O S. CHRYSOBTOMIDES COLD CONIZATION INSTRUMENT This invention relates to a surgical instrument for obtaining a biopsy specimen from the body and, more particularly, for cold conization of the uterus.

It is well known that various instruments have been utilized, as well as numerous surgical procedures, for obtaining biopsy specimens from the cervical s. The previously known instru ments have been inadequate due to the inability of the surgeon to gauge or control the incision or obtain an accurate and well-shaped specimen. Furthermore, the use of manual procedures, for example the surgeon using a scalpel, or some form of existing manual instrument, creates considerable difficulty in that the vacillation of the scalpel necessary for removing the specimen causes a jagged incision which creates a large scar tissue area. In many cases this could require a followup operation. The prior art instruments also have had the disadvantage of effecting puncturing of the opposite side of the cervical canal due to the oscillatory action of the cutting means. Quite obviously, jagged and crude incisions cause excessive bleeding, prevent cauterization and may cause the operation to be stopped for blood control. Moreover, the instruments have an axial slicing motion provide a shallow or narrow angle conical section which generally is insufficient for accurate biopsy testing.

It is an object of this invention to provide a reliable and positively controlled instrument for surgically removing a biopsy specimen from the uterus.

A further object of the invention is to provide a cold conization surgical instrument which prevents stenosis and effects a smooth receptacle for the cauterizing process.

Another object of this invention is to provide a surgical instrument for removing a biopsy specimen that performs in a manner to eliminate undue hemorrhaging during the opera tion, to permit cauterization, elimination of jagged edges on the incision to enhance healing and eliminate scar tissue and which provides a biopsy specimen capable of being accurately tested for cancer and better evaluated for the degree of invasion of cancer.

A still further object of the instant invention is the provision of a surgical instrument utilizing a pneumatic power source, readily available in modern operating rooms, and which effects a constant and uniform reciprocation of cooperating arcuate blades.

Still another object of the instant invention is to provide a surgical instrument which utilizes pneumatic pressure for reciprocating a pair of coordinated arcuate blades held by an adjustably guide positioned to effect removal of a conical biopsy section from the uterus.

In order to overcome the disadvantages of the prior art the instant invention contemplates utilizing a pistol grip body in which is mounted a pneumatic motor connected by a gear train to cooperating, reciprocating blades which can be manually rotated through a 360 arc, with respect to the handle and cervix, to effect removal of a conical biopsy section.

These and other features, objects and advantages of the invention will become more fully evident from the following description with reference being made to the accompanying drawings wherein:

FIG. 1 is an overall diagrammatic view of the novel surgical instrument of the instant invention;

FIG. 2 is an enlarged section taken on line 2-2 of FIG. 1;

FIG. 3 is an enlarged section taken on line 3-3 of FIG. 1;

FIG. 4 is an enlarged side view of a portion of the instant invention;

FIG. 5 is an enlarged section taken on line 5--5 of FIG. 4;

FIG. 6 is a side sectional view of the instant invention;

FIG. 7 is an enlarged sectional view taken on line 77 of FIG. 6;

FIG. 8 is a sectional view taken on line 8-8 of FIG. 6;

FIG. 9 is a sectional view taken on line 9-9 of FIG. 6;

FIG. 10 is a sectional view taken on line I0-10 of FIG. 6;

FIG. 11 is an enlarged side view of the drive end of the blades for the instant invention;

FIG. 12 is a sectional view taken on line l212 of FIG. 10;

and

FIG. 13 is an alternative sectional view taken on line 77 of FIG. 6.

Referring now to the drawings and, more particularly, to FIG. 1 wherein the instant conization instrument is designated by the numeral 10 and shown to include handle 12 having pistol grip l4 and barrel 16 for receiving a conventional pneumatic motor 20, see FIG. 6. Knob 22 extends from the rear of handle 12 and is knurled as at 24 to provide for easy manual rotation of the mechanism housed within barrel 16. It is to be noted that grip 14 includes a pair of

openings

26 and 28 for the respective admission and discharge of air to the interior of barrel 16 of handle 12. Conventional pneumatic connector 30 is utilized to insure positive connection between a source of pneumatic supply, not shown, and instrument 10.

Housing 32 connects with

slides

34 and 38 to permit a reciprocating and coordinated action of blades 50 as will be described more fully hereinafter. Blade guide arm 36 is attached to pneumatic motor 20, see FIG. 6, and extends forwardly to receive the ends of blades 50 as is observed in FIG. 4. Guide arm 36 utilizes blade retainer 40 extending outwardly therefrom for guidance and support of blades 50. Blade guide arm 36 includes elongated circular arm 42 having enlarged cylindrical portion 44 with threads 46 on the exterior at one end of cylinder 44 as can be more clearly seen in FIG. 6. Circular arm 42 has forward guide 52 extending therefrom in one direction with extension 54 projecting outwardly and combining with the rounded end of face 56 and opening 58 while permitting complete sterilization to provide an opening into which blades 50 may extend through slot 60.

Blade guide arm 36 has rear guide or blade retainer 40 extending outwardly therefrom parallel to and in the same direction as forward guide 52. Rear guide 40 has a plurality of slots 64 extending inwardly from one side thereof for receiving blades 50 in a series of positions to thereby effect varying radii for the cone to be removed from the cervical os. Referring to FIG. 2, rear guide 40 has bore 66 for receiving shoulder screw 72 which assists in maintaining retainer plate 62 in position to hold blades 50 in slots 64 as well as permitting pivotal movement of retainer 62 about guide 40 in order to facilitate removal and replacement of blades 50. Retainer 62 is made of spring steel for outward and rotary motion across locking flanges 63. This construction permits rapid removal of blades 50 by a springing action to thus permit retainer 62 to be rotated and facilitate the replacement of blades 50 in slots 64. It is to be understood that retainer 62 with bolt 72 could be eliminated if slots 64 did not extend to the edge of arm 42 such that blades 50 could be inserted through slots 64 from one side.

It is also to be understood that rear guide 40 could be slidable on blade guide arm 36 to accomplish adjustment of the radius of the cone described by blades 50. Such a construction would require a locking mechanism, not shown, having, for example, a resilient pin or ball for engagement with bores spaced longitudinally of arm 36 which could also function as a gauge for the degree of insertion required.

Referring now to FIG. 6 wherein the interior of the instant instrument is shown in section to provide an understanding of the internal mechanism of the instant invention. As noted hereinabove, handle 12 is provided with a pair of

bores

26 and 28 which communicate with an intake area 76 and an exhaust area 78. Connector 30 is threadedly attached to intake bore 26 at the lower portion of pistol grip I4. Handle 12 is of pistol configuration having a cylindrical section 16 on the upper portion thereof. The cylindrical portion or barrel 16 has spaced grooves 80 for receiving O-ring seals 82 in order to positively seal the interior of handle 12. Knob 22 is knurled as at 24 to provide positive and accurate handling by the surgeon operating the instrument. The knob 22 extends inwardly and has shoulder 86 for fitting the barrel 16 of handle 12 adjacent Teflon O-ring seal 82 and extending inwardly such that flange 88 is exteriorly threaded at 90 and is permitted to be positively attached to cylindrical housing by internal threads 102 at the rear edge thereof. Housing I00 fits within and is permitted to freely rotate within cylinder 16 because of the Teflon O- rings 82 while effecting positive connection by the engagement of threads 90 and 102 and yet is completely sealed by utilization of the O-rings.

Housing 100 is threadedly attached to flange 104 of retainer 110 which has shoulder 106 for abutment against barrel 16 and the forward O-ring seal 82 and for autoclave sterilization. Threads 112 on the exterior of flange 104 engage internal threads 114 at the forward edge of housing 100 to effect a positive connection therebetween. Retainer 110 has longitudinal bore 116 therein which is interiorly threaded at 118 to receive threads 46 on the exterior of enlarged cylindrical portion 44 of blade guide arm 36. This construction provides a continuous member from knob 22 to forward guide 52 which is capable of completely sealed, free rotation in either direction around longitudinal centerline 120 as will be more fully apparent from the description hereinafter.

Mounted within housing 100 are rear plate 124 and forward plate 126 between which and within cylinder 100 is mounted conventional pneumatic rotor 130 and rotor blade 132 to function as the pneumatic power source. Rotor 130 has shaft 134 extending rearwardly therefrom for receiving nut 136 which accurately locates rear bearing 138 on shaft 134 and against rear plate 124 within flange 142. Shaft 144 extends forwardly from rotor 130 and cooperates with forward bearing 146 that permits rotation of shaft 144 and rotor 130 within flange 152 of front plate 126.

Spacer I50 fits forwardly of bearing 146 and surrounds shaft 144. Forward rotor shaft 144 is provided with teeth 148 for mating engagement with teeth 162 on planet wheel 160 that operates within internal gear 164 having teeth 166. Pin 168 functions as an axle for the rotary attachment of planet wheel 160 to planet cage 170. This construction provides a reduction gear for slowing down the reciprocation of blades 50 as will be more fully understood hereinafter.

A pair of ball bearing races 172 are mounted about planet cage 170 with spacer 174 insuring proper location of bearings 172. Planet cage 170 is affixed to drive shaft 180 which runs along centerline 120 of housing 32, barrel l6, slides 34 and 38 and blade guide arm 36. Drive shaft 180 is adapted for rotation within enlarged cylindrical portion 44 of blade guide arm 36 by ball bearing races 182 in a manner similar to that by which bearings 172 permit planet cage 170 to rotate with shaft 180 in lock retainer 110. Ring spacer 194 has external threads 196 for engaging internal threads 119 on enlarged cylindrical portion 44 to properly locate bearing 182 on shoulder 184.

Cam 188 is mounted centrally of forward portion 192 of drive shaft 180 and has groove 190 therein to provide harmonic motion for a purpose to be described hereinafter. As rotor 130 is rotated by the pneumatic pressure, forward shaft 144 effects rotation of planet wheel 160 which is attached by pin 168 to planet cage 170 which in turn is attached to drive shaft 180 and thus rotor 130 effects rotation of drive shaft 180 and cam 188. It is to be further noted that internal gear 164 maintains a positive connection between forward shaft 144 and internal planet wheel 160.

Forward slide 34 has cylindrical body 200 with blade retainer 202 extending outwardly therefrom. Forward slide 34 is mounted over enlarged cylindrical portion 44 of blade guide arm 36 with retainer 202 parallel and extending in the same direction as forward guide 52 and rear guide 40 to function as will be noted hereinafter. Rear slide 38 has cylindrical body 204 that fits over and slides on forward slide 34 with blade retainer 206 extending therefrom parallel and in close proximity to blade retainer 202 on forward slide 34. Forward slide 34 is provided with elongated slot 210 in body 200 in order that screw 212 may be rigidly attached to real slide 38. As is apparent from FIG. 6, enlarged cylindrical portion 44 of blade guide arm 36 has slot 214 therein to permit screw 212 to extend through both forward guide 34 and cylindrical portion 44 into groove 190 in cam 188. Slot 214 in cylindrical portion 44 prevents undesirable rotation of arm 36 in

guides

34 and 38. These two slots, 210 and 214, are in a coinciding relationship and of sufficient length to permit end 216 of screw 212 to be fully operative in groove 190 of cam 188 to effect equalized reciprocating action of rear slide 38 with regard to forward slide 34.

Enlarged cylindrical portion 44 of blade guide arm 36 has slot 220. diametrically opposite slot 214 and extending longitudinally of enlarged portion 44 to permit retainer pin 222, extending from forward slide 34, to be positioned in groove 190 of cam 188. It is thus seen that pin 222 in groove 190 effects movement of forward slide 34 and blade retainer member 202 thereonand pin 212 in groove 190 of cam 188 effects movement of rear slide .38 and blade retainer 206.

In order to insure positive action and prevent vacillation or unsymmetrical movement of cam 188 which might cause a binding thereof and effect improper reciprocation of

blades

48 and 50, roller bearing 230 is mounted inside of enlarged cylindrical portion 44 of blade guide arm 36 and receives the extreme forward end 326 of drive shaft 180 to provide location of drive shaft 180. Nut 232 engages threads 234 on shaft 180 and is utilized to maintain cam 188 in its proper location on forward portion 192 of drive shaft 180 and against bearing 182 at the rearward end of cam 188. Drive lockpin 186 is utilized to lock cam 188 to drive shaft 180 and thereby prevent any slipping or play between cam 188 and drive shaft 180.

Blade retainers

202 and 206 are quite similar and function to impart reciprocating motion to inner blade 48 and outer blade 50, respectively, in the same plane. Forward slide 34 has blade retainer 202 mounted thereon utilizing pin 240 which extends through a substantially circular aperture 242 in inner blade 48 and through an elongated slot 244 extending longitudinally of outer blade 50, see FIG. 11. This construction effects a positive connection between retainer 202 and the respective pin 240 with inner blade 48, but outer blade 50, because of slot 244 is not affected. Similarly, blade retainer 206 utilizes pin 246 extending therethrough to fit within circular aperture 247, substantially the size of pin 246, to permit rear slide 38 to drive outer blade 50 for reciprocal movement. Inner blade 48 is provided with an elongated longitudinal slot 248 in approximately the location of aperture 247 in blade 50 to thereby permit rear slide retainer 206 to move with its associated pin 246 without imparting motion or having any effect on inner blade 48. Thus it is seen that due to the rotary motion of cam 188, pins 212 and 222, respectively, effect a vacillating, longitudinal motion of rear slide 38 and forward slide 34. This reverse reciprocation of

slides

34 and 38 and their

attendant blade retainers

202 and 206 effects an alternate reciprocating motion of

blades

48 and 50 to thereby permit serrations 250 on

blades

48 and 50 to effect a smooth and rapid incision which eliminates any undue bleeding or scar tissues upon healing of the cervical os after removal of a biopsy specimen and permits the blades to cut tougher tissue when necessary. Exceptionally tough tissue may be compensated for by increasing pneumatic pressure which increases the revolutions per minute and, therefore, reciprocation of

blades

48 and 50.

Referring to FIGS. 6 and 7,

blade retainers

202 and 206 are substantially identical in that they respectively utilize

pins

240 and 246 for holding the respective inner blade 48 and outer blade 50 in position. Pin 240 extends inwardly perpendicular to longitudinal centerline of instrument 10 and through base structure 252 and has on the outer end thereof handle 254 to facilitate grasping and movement of pin 240. Pin 240 has groove 256 therein for receiving pin 258 which is attached to arm 260 such that lateral movement of arm 260 will effect removal of pin 258 from groove 256 and thereby permit handle 254 to be moved such that pin 240 is withdrawn from the aperture and slot in

blades

48 and 50 to permit rapid replacement of the blades when necessary.

Utilization of different slots 64 in rear guide 40 and the for ward end of

blades

48 and 50 being inserted into extension 54 and thelocation of

blade retainers

202 and 206 permits a variation of the radius of the conical section removed from the cervical canal. Blade retainer 202' is shown in FIG. 13 as having pin 240' for holding inner blade 48 in position. Pin 240' has handle 254' and extends through base structure 252' which has threaded bore 280 for receiving lock member 282. Lock member 282 has cylindrical opening 286 in which is located spring 288 and ball 290. Ball 290 mates in groove 292 in pin 240 to permit release thereof for rapidly changing

blades

48 and 50. It is to be understood that blade retainer 206 is identical to retainer 202 irrespective of which alternative embodiment is utilized.

OPERATION The instant invention provides an easily maintained, in a sterile condition, novel instrument utilizing pneumatic power for effectively removing a conical cancer biopsy specimen to permit a laboratory to determine the malignancy or existence of cancer at the uterus. The invention operates substantially as would be anticipated from the description hereinabove in that pneumatic pressure from a readily available source in the operating room enters handle 12 through connector 30 and flows into chamber 76 where it is permitted to flow around rotor 130 and impinge blade 132 to effectively rotate rotor 130 and the attendant forward shaft 144. Shaft 144 effects movement of planet wheel 160 in internal gear 164 providing a positive gearing of the mechanism at this location. Pin 168 positively connects wheel 160 to planetary cage 170 which is attached to drive shaft 180 such that as forward shaft 144 rotates, wheel 160 moves about the internal surface of cylindrical internal gear 164 to effect a complete rotation of planetary cage 170. As planetary cage 170 rotates it effects rotation of drive shaft 180. Because cam 188 is rigidly attached to drive shaft 180, cam 188 is caused to rotate at the same rate as drive shaft 180. The revolving of harmonic cam 188 effects movement of

pins

212 and 222, which slide in diametrically opposite locations of groove 190 to cause rear slide 38 and forward slide 34 to reciprocate in the direction of centerline 120 such that they are 180 out of phase with one another. That is, as seen in FIG. 6, blade retainer 202 on forward slide 34, and its attendant pin 222, are completely forward when retainer 206 on rear slide 38 and its associated pin 212 are fully to the rear, and vice versa.

The construction of blades 48 and S0 cooperates with the location of

retainers

202 and 206 to effect reciprocation of

blades

48 and 50 as noted above. Blade 48, see FIG. 6, is in.a forward position because forward slide 34, retainer 202 and pin 240 are forward and outer blade 50 is in its rearmost position and rear slide 38 with its attendant retainer 206 is in the rearward position. As drive shaft 180 rotates cam 188, groove 190 establishes a harmonic motion and causes pin 212 to move forward and pin 222 to move to the rear or the left as seen in FIG. 6. Because of

slots

244 and 248 in

blades

50 and 48, respectively, inner blade 48 is moved to the rear with forward slide 34 and outer blade 50 is moved forward with rear slide 38. Thus it is seen that as drive shaft 180 rotates cam I88, groove 190 effects a harmonic motion and causes forward slide 34 and rear slide 38 to slide upon one another in a direction parallel to longitudinal centerline 120 of instrument 10. This motion of

slides

34 and 38 effects a reciprocating, sliding action of blades 48.and 50 which, through serrations 250 thereon, are able to sever the flesh and material around the uterus to thereby efiectively and rapidly remove a conical biopsy specimen.

It is to be observed especially from FIGS. 1 and 6 that knob 22 with knurls 24 thereon permits an easy and positive grip of knob 22 which is connected to cylindrical housing 100 which is connected to retainer 110 connected by threads 118 to enlarge cylindrical portion 44 of blade guide arm 36. Because of the slotted construction of forward slide 34 and rear slide 38, accomplished through

slots

210, 214 and 220, the rotation of knob 22 effects a rotation of blade guide arm 36, forward slide 34 and rear slide 38 and this rotary motion of these elements about centerline I effects movement of

blades

48 and 50 in a similar rotary manner.

Thus it is seen that insertion'of guide 52 into the cervical canal and the application of pneumatic pressure through inlet 26 into intake area 76 for impinging on blade 172 effects the rotation of rotor and drive shaft which rotates ca'rn 188 and effects longitudinal reciprocation of

slides

34 and 38 to accomplish a smooth, neat incision with minimal bleeding. The surgeon rotates knob 22, with one hand while holding handle 12 with the other, to effect rotation of

blades

48 and 50 about longitudinal centerline 120 such that

blades

48 and 50 describe a 360 conical section to thereby rapidly and effciently remove a biopsy specimen from the cervical os with minimal effort and bleeding. Additionally, the smooth incision accomplished by the novel conization instrument l0 eliminates the requirement for futuresurgery and eliminates stenosis while permitting a better receptacle for cauterization. Furthermore, rounded end face 56 protects the opposite wall of the uterine canal from being punctured by the ends of

blades

48 and 50 to reduce trauma and enhancinghealing.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

l. A cold conization instrument for removal of a conical biopsy specimen from the uterus comprising: handle means having a grip, a barrel and a pair of. closely adjacent slidably movable cutting blade means, said barrel having a rotatable guide arm, a forward blade-receiving guide means on one end of said guide arm and a motion-transmitting means on the other end of said guide arm; a blade support and retainer means intermediate of and extending from said guide means, said forward blade guide means and said blade retainer means constituting a means defining an arcuate path for said pair of cutting blade means said motion-transmitting means having rotation means at one end and cutting blade-mounting means on the other end all being freely rotatable in either direction with said guide arm pneumatic motor means connected to said motion-transmitting means for providing rotary motion; cam means for transforming the rotary motion to linear motion; and reciprocating means for applying the linear motion to said arcuate cutting means, whereby rotation and linear motion of said blade means effect efficient removal of a conical biopsy specimen. i

2. The conization instrument of claim 1 wherein said pneumatic motor means are mounted with a cylindrical housing; drive shaft means attached to said motor means by connecting means; said cam means attached to said drive shaft means and said reciprocating means. i

3. The conization instrument of claim 1 wherein the flat sides of the cutting blade means are substantially horizontal when the handle means is vertical and further including adjustment means for altering the degree of arc of said cutting means to adjust the dimensions of the conical section removed in accordance with amount of tissue or thickness of specimen required.

4. The conization instrument of claim 2 wherein said continuous means includes reduction gear means for obtaining proper rotary motion.

5. The conization instrument of claim 1 in which said motion-transmitting means includes housing means attached to said rotation means and enco'mpassingsaid pneumatic motor I means; a lock retainer secured to said housing means on the end thereof opposite from said rotation means for accurately maintaining the position of said pneumatic motor means; arm means attached to said lock retainer means; and said reciprocating means mounted on said arm means for driving said cutting means.

6. The-conization instrument of claim .1 wherein said arcuate cutting means comprises: a pair of blades including an inner blade having an elongated slot spaced from one end thereof; an aperture for receiving a lockpin spaced from said slot toward the other end of said blades; the other of said pair of blades having an aperture for receiving a lockpin adjacent one end thereof; an elongated slot spaced from said aperture toward the other end of said blade; and each of said blades having serrations adjacent the other of said ends thereof,

whereby reciprocating action of said reciprocating means effects reciprocation of said blades for rapid and smooth removal of a conical biopsy specimen.

7. The conization instrument of claim 6 wherein said reciprocating means comprises a forward slide having a retainer thereon for attachment to one of said blades; a rear slide having a retainer thereon for operation of the other of said pair of blades.

8. The conization instrument of claim 7 wherein I said reciprocating means includes pins extending inwardly from each of said slides .for sliding movement in a groove in said cam means.

9. The conization instrument of claim 8 wherein said arm means includes a pair of diametrically opposed elongated slots adjacent to but spaced from the end attached to said lock retainer means; said forward slide having a slot therein in communication with one of said pair of slots in said arm means whereby said rear slide pin may extend through said slots into said groove in said cam means and said pin is permitted reciprocal movement along the centerline of said instrument.

10. The conization instrument of claim 6 including ring means on the interior of said arm means; bearing means mounted around said drive shaft means and held by said ring means against said cam means; a nut threadedly engaging the end of said drive shaft means for fixedly locating said cam means against said bearing means on said drive shaft.

Claims

1. A cold conization instrument for removal of a conical biopsy specimen from the uterus comprising: handle means having a grip, a barrel and a pair of closely adjacent slidably movable cutting blade means, said barrel having a rotatable guide arm, a forward blade-receiving guide means on one end of said guide arm and a motion-transmitting means on the other end of said guide arm; a blade support and retainer means intermediate of and extending from said guide means, said forward blade guide means and said blade retainer means constituting a means defining an arcuate path for said pair of cutting blade means said motiontransmitting means having rotation means at one end and cutting blade-mounting means on the other end all being freely rotatable in either direction with said guide arm pneumatic motor means connected to said motion-transmitting means for providing rotary motion; cam means for transforming the rotary motion to linear motion; and reciprocating means for applying the linear motion to said arcuate cutting means, whereby rotation and linear motion of said blade means effect efficient removal of a conical biopsy specimen.

2. The conization instrument of claim 1 wherein said pneumatic motor means are mounted with a cylindrical housing; drive shaft means attached to said motor means by connecting means; said cam means attached to said drive shaft means and said reciprocating means.

5. The conization instrument of claim 1 in which said motion-transmitting means includes housing means attached to said rotation means and encompassing said pneumatic motor means; a lock retainer secured to said housing means on the end thereof opposite from said rotation means for accurately maintaining the position of said pneumatic motor means; arm means attached to said lock retainer means; and said reciprocating means mounted on said arm means for driving said cutting means.

6. The conization instrument of claim 1 wherein said arcuate cutting means comprises: a pair of blades including an inner blade having an elongated slot spaced from one end thereof; an aperture for receiving a lockpin spaced from said slot toward the other end of said blades; the other of said pair of blades having an aperture for receiving a lockpin adjacent one end thereof; an elongated slot spaced from said aperture toward the other end of said blade; and each of said blades having serrations adjacent the other of said ends thereof, whereby reciprocating action of said reciprocating means effects reciprocation of said blades for rapid and smooth removal of a conical biopsy specimen.

8. The conization instrument of claim 7 wherein said reciprocating means includes pins extending inwardly from each of said slides for sliding movement in a groove in said cam means.