Surgical instrument - Patent Review 5611813

What is claimed is:

1. A surgical instrument for performing electrosurgery comprising:

a handle housing with a first handle member affixed thereto, and at least first and second concentrically arranged shafts extending longitudinally away from said housing, said second shaft having proximal and distal ends and being affixed to said housing at its proximal end so as to be immobile with respect to said housing, and said first shaft surrounding said second shaft and being arranged to translate longitudinally with respect to said second shaft;

a jaw unit carried by said distal end of said second shaft, said jaw unit comprising at least two jaws, a rear section, and intermediate leaf spring elements connecting each of said jaws to said rear section, said leaf spring elements biasing said jaws so that when said leaf spring elements are unrestrained, said jaws are deployed in angular spaced relation with one another;

said first shaft having a length such that when said first shaft is caused to translate towards the distal end of said second shaft, the distal end of said first shaft will slide over said jaw unit and mechanically cause said jaws to close towards one another;

translation means for causing said first shaft to translate longitudinally relative to said second shaft, said translation means comprising a second handle member mounted for pivotal movement relative to said first handle member, and means coupling said second handle member and said first shaft for causing reciprocal movement of said first shaft relative to said second shaft as said second handle member is pivoted relative to said first handle member, whereby to cause said first shaft to move into and out of jaw-closing relation with said jaws; and

electrically-conductive means carried in part by said handle housing for applying an electrical potential to said jaws, whereby an electrical current will flow in tissue engaged by said jaws.

2. An instrument according to claim 1 wherein said electrically-conductive means comprise electrical connector means mounted in said handle housing, and means for electrically connecting said electrical connector means to said second shaft.

3. A surgical instrument according to claim 2 comprising retaining means for releasably retaining said electrical connector means in said housing.

4. A surgical instrument for performing bipolar electrosurgery on tissue comprising:

a housing provided with an internal bore,

first and second concentrically arranged tubular elements within said bore, said first and second tubular elements each having a proximal end and a distal end, with said first tubular element being immobile with respect to said housing and said second tubular element being capable of translating axially relative to said first tubular element;

means attached to said housing for causing said second tubular element to translate axially relative to said first tubular element;

a jaw head comprising first and second separately formed jaws, with said jaws being spring biased so as to normally occupy an open position relative to one another;

means connecting said jaw head to the distal end of one of said tubular elements;

said first and second tubular elements being disposed so that they can undergo relative axial movement bidirectionally and so that when said they undergo relative axial movement in a first direction, said second tubular element will force said jaws to close towards one another; and

electrically-conductive means carried by said housing for applying an electrical potential to said jaws, said electrically-conductive means being arranged for connection to an external source of electrical power.

5. An instrument according to claim 4 comprising insulation means disposed so as to prevent one jaw from physically contacting the other jaw.

6. A surgical instrument for performing electrosurgery comprising:

a hollow outer shaft having a longitudinal axis, a first proximal end and a first distal end;

a hollow inner shaft coaxially disposed in said outer shaft for reciprocal movement with respect to said outer shaft, said inner shaft having a second proximal end and a second distal end;

means for surgical interaction with animal tissue associated with said first and second distal ends, said surgical interaction means comprising first and second tissue-interacting members movable relative to one another between a first open position and a second closed position by axially directed changes in the relative positions of said first and said second distal ends;

a handle mechanism coupled to said outer and inner shafts for effecting relative axial movement of said shafts and thereby changing the relative positions of said first and said second distal ends lengthwise of said longitudinal axis;

said handle mechanism comprising a first handle member affixed to the proximal end of one of said shafts, driver-responsive means attached to the other of said shafts, a second handle member movable relative to said first handle member between first and second operating positions, driver means carried by said second handle member engageable with said driver-responsive means for effecting reciprocal axial movement of said other shaft relative to said one shaft in response to movement of said first handle member between said first and second operating positions;

unidirectional locking means for locking said first and second handle members against relative movement in one predetermined direction; and

electrically-conductive means carried in part by a handle housing for applying an electrical potential across said tissue-interacting members, whereby an electrical current will flow through tissue engaged by said tissue-interacting members.

7. An instrument according to claim 6 wherein said first and second tissue-interacting members comprise first and second electrically conductive jaw members mounted to the distal end of said inner shaft and electrically insulated from one another, and said electrically-conductive means comprises first electrical conductor means connected to said first jaw member and second electrical conductor means connected to said second jaw member.

8. An instrument according to claim 7 wherein said first and second jaw members comprise first and second electrically-conducting leaf spring members and first and second electrically-conducting jaws carried by said first and second leaf spring member respectively, and further including an insulating member attached to the distal end of said inner shaft for supporting said jaw members on the distal end of said inner shaft.

9. An instrument according to claim 7 wherein said inner shaft is electrically conductive and said second jaw member is electrically coupled to said inner shaft.

10. An instrument according to claim 7 wherein said first electrical conductor is a cable that extends along the interior of said inner shaft and is connected to said first jaw member.

11. An instrument according to claim 6 wherein at least one space exists between said outer and inner shafts, and further including means for introducing fluid to or removing fluid from said at least one space.

12. An instrument according to claim 11 further characterized by at least one radially-extending opening in said outer shaft, and a collar assembly surrounding said outer shaft, said collar assembly having a chamber that communicates with said at least one radially-extending opening and a port that permits fluid to be introduced to or removed from said chamber.

13. An instrument according to claim 12 wherein said collar assembly is provided with a fitting that is coupled to said port and is adapted to be connected to an auxiliary device.

14. A surgical instrument comprising:

a hollow outer shaft having a longitudinal axis, a first proximal end, and a first distal end;

an inner shaft coaxially disposed in said outer shaft, said inner shaft having a second proximal end and a second distal end;

means for surgical interaction with animal tissue attached to the distal end of said inner shaft, said surgical interaction means comprising first and second tissue-interacting members movable relative to one another between a first open position and a second closed position by axially directed changes in the relative positions of said first and said second distal ends of said shafts; and

a handle mechanism coupled to said outer and inner shafts for effecting relative axial movement of said shafts and thereby changing the relative positions of said first and said second distal ends lengthwise of said longitudinal axis;

said handle mechanism comprising a housing that surrounds the proximal ends of said shafts, means securing one of said shafts to said housing so as to prevent movement thereof relative to said housing, a first handle member affixed to said housing, driver-responsive means attached the other of said shafts, a second handle member, pivot means connecting said second handle member to said first handle member, said second handle member being movable on its pivot relative to said first handle member between first and second operating positions, driver means carried by said second handle member engageable with said driver-responsive means for effecting axial movement of said other shaft relative to said one shaft in response to movement of said second handle member from one to the other of said first and second operating positions; and

unidirectional locking means for locking said first and second shafts against relative axial movement in one predetermined direction; and

bi-polar electrically-conductive means for applying an electrical potential difference across said tissue-interacting members, whereby an electrical current will flow through tissue engaged by said tissue-interacting members.

15. A surgical instrument comprising:

a handle housing with a first handle member affixed thereto, and at least first and second concentrically arranged shafts extending longitudinally away from said housing, said first and second shafts each having proximal and distal ends; a jaw unit carried by said distal end of said second shaft, said jaw unit comprising first and second jaw members with at least portions of said jaw members being electrically conductive;

means for causing one of said shafts to translate axially relative to the other of said shafts whereby said first shaft will act on said jaw members so as to cause said jaw members to close on one another when said translation is in a first axial direction; and

means for connecting said electrically conductive portions of said jaw members to sources of electrical potential, whereby if different electrical potentials are applied to said jaw members an electrical current will flow between said jaw members to electrify a subject matter disposed between and engaged by said jaw members.

16. An instrument according to claim 15 wherein said jaw members are spring-biased to a normally open position.

17. A surgical instrument for conducting electrosurgery comprising:

a handle housing;

a first outer shaft and a second inner shaft having corresponding proximal and distal ends with said proximal ends being supported by said housing, with one of said shafts being movable axially relative to the other;

a jaw unit carried by one of said shafts, said jaw unit comprising at least first and second jaws with said jaws normally being deployed in spaced relation to one another in an open position;

manually operable means for causing relative axial movement of said shafts in a first axial direction or a second axial direction;

said outer shaft being disposed so as to extend over said jaws when said shafts undergo relative movement in said first axial direction, whereby when said shafts undergo relative movement in said first axial direction said outer shaft will cause said jaws to close towards one another; and

means carried by said handle and extending along said second shaft for connecting said first and second jaws to different sources of electrical potential.

18. An instrument according to claim 17 wherein said last-mentioned means comprises first and second electrical leads disposed within said second shaft and connected to said first and second jaws.

19. An instrument according to claim 17 wherein said last-mentioned means comprises first and second electrical leads disposed within said second shaft and connected to said first and second jaws, and a bi-polar connector assembly attached to and projecting from said handle housing, said leads being connected to said connector assembly, whereby said jaws will be electrified with a potential difference between them when said connector assembly is coupled to a d.c. electrical power source.

20. An instrument according to claim 17 further including means electrically insulating said jaws from one another.

21. An instrument according to claim 20 wherein said jaws have proximal ends and distal ends, and further wherein said last-mentioned means comprises a mechanical member disposed between the proximal ends of said jaws.

22. An instrument according to claim 17 wherein said distal end of said inner shaft has a hollow extension, and said jaw unit comprises a pair of jaws each having a proximal end and a distal end, with said proximal ends extending into said hollow extension.

23. A surgical instrument comprising:

a hollow outer shaft having a longitudinal axis, a first proximal end and a first distal end;

an inner shaft coaxially disposed in said outer shaft with a space existing between said shafts, said inner shaft having a longitudinal axis, a second proximal end, and a second distal end, said shafts being disposed for relative axial movement;

means for surgical interaction with animal tissue attached to the distal end of said inner shaft, said surgical interaction means comprising first and second tissue interacting members movable relative to one another between a first open position and a second closed position by axially directed changes in the relative positions of said first and said second distal ends;

a handle mechanism coupled to said outer and inner shafts for effecting relative axial movement of said shafts and thereby changing the relative positions of said first and said second distal ends lengthwise of said longitudinal axis;

said handle mechanism comprising a first handle member affixed to the proximal end of said inner shaft, driver-responsive means attached to said outer shaft, a second handle member pivotally connected to said first handle member and movable relative to said first handle member between first and second operating positions, driver means carried by said second handle member engageable with said driver-responsive means for effecting reciprocal axial movement of said outer shaft relative to said inner shaft in response to movement of said first handle member between said first and second operating positions; and unidirectional locking means for locking said first and second handle members against relative movement in one predetermined direction; and

means for introducing fluid to or removing fluid from said space.

24. An instrument according to claim 23 further characterized by at least one radially-extending opening in said outer shaft, and a collar assembly surrounding said outer shaft, said collar assembly having a chamber that communicates with said at least one radially-extending opening and a port that permits fluid to be introduced to or removed from said chamber.

25. A surgical instrument for conducting electrosurgery comprising:

a handle assembly;

an elongate dual shaft assembly having a proximal end retained within said handle assembly and a distal end to which is mounted a jaw assembly having at least two jaws that are movable relative to one another between open and closed positions, said shaft assembly comprising inner and outer shafts with one shaft movable axially relative to the other and said jaw assembly being arranged so that said jaws are urged to a closed position when said shafts undergo relative axial movement in a first direction, said handle assembly being operable to provide relative axial motion between said inner and outer shafts;

a ratchet device coupled between said dual shaft assembly and said handle assembly at the proximal end of said shaft assembly within said handle assembly, said ratchet device comprising a first member comprising a plurality of teeth, and a second member engageable with the teeth on said first member, said first and second members being movable relative to one another as the shafts undergo relative axial movement in response to operation of said handle assembly, the relative motion between said first and second members causing locking engagement and disengagement of said second member and said teeth, and said teeth and said second member being arranged so that when they are engaged the ratchet device will allow the shafts to undergo relative axial movement in said first direction but prevent the shafts from undergoing relative axial movement in a second opposite direction; and

first and second means carried by said handle assembly for applying an electrical potential across said jaws.

26. A surgical instrument according to claim 25 further including selectively operable means for preventing engagement of said teeth and said second member, whereby said shafts are free to be moved axially relative to one another in said first or second directions by operation of said handle assembly.

27. A surgical instrument comprising:

a hollow outer shaft having a longitudinal axis, a first proximal end, and a first distal end;

an inner shaft coaxially disposed in said outer shaft, said inner shaft having a longitudinal axis, a second proximal end and a second distal end, said shafts being capable of relative reciprocal axial movement;

means for surgical interaction with animal tissue attached to the forward end of one of said shafts, said surgical interaction means comprising first and second tissue interacting members movable relative to one another between a first open position and a second closed position by axially directed changes in the relative positions of said first and said second distal ends; and

a handle mechanism coupled to said outer and inner shafts for effecting relative axial movement of said shafts and thereby changing the relative positions of said first and said second distal ends lengthwise of said longitudinal axis;

said handle mechanism comprising a first handle member affixed to the proximal end of one of said shafts, driver-responsive means attached to the other of said shafts, a second handle member, means mounting said second handle member so that it is movable relative to said first handle member between first and second operating positions, driver means carried by said second handle member engageable with said driver-responsive means for effecting reciprocal axial movement of said other shaft relative to said one shaft in response to movement of said second handle member between said first and second operating positions;

ratchet means located within a housing for preventing relative axial movement of said shafts in one predetermined axial direction while permitting relative axial movement in a second opposite axial direction; and

means carried by said handle mechanism for applying an electrical potential between said first and second tissue-interacting members.

28. An instrument according to claim 27 further including selectively operable means for disabling said ratchet means so as to free said other shaft for axial movement in said one predetermined axial direction.

Description Submit all comments and votes

This invention relates to surgical instruments for manipulating tissue and other objects and more particularly to improvements in instruments such as graspers and forceps for facilitating freedom of the hands of the surgeon and also for conducting electrosurgery.

My prior application Ser. No. 07/869,535 relates to an improved grasper-type instrument which is characterized by a unitary piece jaw comprising two jaws, a rear section, and two intermediate leaf spring sections each connecting a different jaw to the rear section of the jaw piece, with the jaw piece being affixed to one end of a first shaft that is in telescoping arrangement with a second shaft, whereby when the second shaft is caused to translate toward the distal end of the first shaft, the second shaft will slide over the jaws and cause them to close toward one another.

BACKGROUND OF THE INVENTION

As used herein, the term "tissue and other objects" means and includes human or animal organs, blood vessels, bones, tendons, ligaments and connective or covering tissue or skin as examples of tissue, and sutures, needles, staples, implants, surgical devices and foreign bodies such as shrapnel or bullet fragments, as examples of "other objects". Also as used herein, the term "electrosurgery" means and includes electro-cauterization and electro-cutting of tissue.

During surgical operations, it is often necessary for the surgeon to be able to manipulate blood vessels, ligaments or other tissue precisely, particularly when the surgeon is relatively remote from the surgical site, as is the case in performing endoscopic procedures. As used herein, the term "manipulate" includes such functions as grasping, clamping, cutting and suturing. Among the instruments that are used for manipulating as herein defined are graspers, forceps, clamps, dissectors, incisors, scissors, cauterizers, needle holders, etc. Often the manipulating is achieved by means of an instrument having a two-part handle mechanism, a tissue-interacting head comprising two or more tissue-interacting members (e.g., jaws), and a head supporting and operating means coupling the handle mechanism and the tissue-interacting head for causing the tissue-interacting members to be moved into and out of a closed relation with one another by the surgeon's manipulation of the handle mechanism.

In a typical prior art instrument, the head supporting and operating means comprises a first shaft fixed to one part of the handle mechanism, a second operating shaft disposed in coaxial and telescopic relation with the first shaft, and means connecting the second shaft to the other part of the handle mechanism, so that telescoping movement of one shaft relative to the other shaft is produced when the two parts of the handle mechanism are moved toward and away from one another, with the two shafts coacting to cause opening and closing of the tissue-interacting members according to the direction of telescoping movement of one shaft relative to the other. In one typical grasper construction, two jaws are pivotally attached to one end of an outer hollow shaft, and a linkage operated by an inner shaft causes the jaws to be opened or closed in response to telescoping movement of the inner and outer shafts. In another grasper construction, the jaw mechanism comprises a pair of spring-like jaws carried entirely by the inner shaft, with the outer shaft acting as a collar to provide a collet-like action whereby (a) the jaws are forced together when the inner and outer shafts undergo relative telescoping movement in one direction and (b) the jaws are released so as to allow them to open when the telescoping movement is in the reverse direction.

A number of surgical instruments designed to grasp or otherwise manipulate tissue, are commonly provided with some form of locking means for locking the jaws in a gripping position, so that during a surgical procedure, the surgeon may let go of the instrument to attend to some other task in the same surgical procedure without fear of the instrument failing to retain its grip. Various forms of locking means have been used in prior surgical instruments, e.g., interlocking ratchet teeth on confronting handles of a two-part handle mechanism of the type where each handle has a hole for accommodating a finger or thumb of the surgeon. Other types of locking means may require or use a lever or a button element for engaging or disengaging the locking means.

Many surgical instruments utilize a scissors-like handle design having two pivotally connected handle members with finger loops for enabling the surgeon to grip and manipulate the handle members. Other surgical instruments have so-called "pistol-grip" handle mechanisms, which offer certain advantages over scissors-type handle designs.

Prior surgical instruments, particularly those of the grasper or dissector type, frequently employ electrical elements for electrifying selected portions of the distal end of the instrument for electrosurgery purposes. Some prior art instruments are necessarily limited to monopolar electrification where the patient's body is electrically grounded, while others are adapted for bipolar electrification.

Prior surgical instruments of the foregoing type have been characterized by one or more limitations and disadvantages, such as the possibility of the patient being traumatized as a result of the surgeon exerting excessive manual strength on the handles of the instrument, causing tissue to be grasped too tightly. Another disadvantage is that some prior locking mechanisms which require the surgeon to operate a separate control such as a lever or button to engage or disengage the locking mechanism, are so constructed that the location or construction of such lever or button may render the instrument less comfortable or easy to hold and/or maneuver. Still other forms of prior instruments of the type to which the invention relates suffer from the fact that they are not well adapted for electrosurgery or cannot be adapted for both monopolar and bipolar electrosurgery. Other instruments have the disadvantage that they have handle designs which are uncomfortable to hold or which are difficult to hold steady when the handle mechanism is being actuated.

Prior handle mechanism designs also suffer from the fact that they are not suited for multi-purpose instruments.

SUMMARY OF THE INVENTION

A primary object of the invention is to provide an instrument which improves upon the instruments disclosed in my prior copending application Ser. No. 07/869,535. Now U.S. Pat. No. 5,318,589.

Another primary object is to provide a novel handle mechanism for a variety of surgical instruments.

Another object of the invention is to provide an instrument which combines grasping jaws and an improved handle mechanism comprising means remote from the jaws for causing the jaws to open and close in a predetermined manner.

Still another object of the invention is to provide an improved surgical instrument for grasping or otherwise manipulating tissue which has a novel handle mechanism that can be held and operated in either a scissors or a pistol-grip manner.

Still another object is to improve upon surgical instruments of the type comprising a pair of movable jaws or blades and a pair of telescoping shafts for supporting and operating the jaws by providing a handle arrangement that can be adapted to provide four different telescoping motions.

A further object of the invention is to improve on surgical instruments of the type characterized by two or more movable interacting elements (e.g., jaws) and means including a handle assembly for moving those elements into and out of interacting relation with tissue or other objects, by providing a novel handle mechanism comprising first and second handle members and an automatic locking means whereby when the handle members have been moved to place the interacting elements in a predetermined tissue (or object)-engaging position, the two handle members and hence the interacting elements are automatically locked against reverse movement, so that if the surgeon removes his hand from the instrument, the interacting elements will remain in engagement with the tissue or other object.

Still another object is to provide an improved surgical instrument of the type having a pair of jaws, a handle mechanism comprising first and second handle members movable relative to one another, and a jaw supporting and operating means connecting the jaws to the handle mechanism whereby the jaws are opened and closed by relative movement of the handle members, characterized in that the handle mechanism comprises means for incrementally locking the jaws in grasping relation with tissue or other objects as the handle members are moved relative to one another, and also means for electrifying the tool for electrosurgery purposes.

A further object is to provide a multipurpose surgical instrument and/or an instrument that may be adapted for monopolar or bipolar electrosurgery purposes.

The foregoing and other objects and advantages are achieved by an improved surgical instrument that essentially is characterized by first and second shafts disposed in axial telescoping relation with one another, a jaw assembly or head at the distal (front) end of the first shaft, with the proximal (rear) end of the first shaft being affixed to a novel handle mechanism that is also coupled to the second shaft, so that manipulation of the handle mechanism by the surgeon will cause the second shaft to reciprocate axially relative to the first shaft, thereby resulting in opening and closing of the jaw assembly. The jaw assembly preferably comprises two diametrically opposed jaws capable of being moved toward and away from one another, but may comprise more than two jaws capable of similar movement. The handle mechanism comprises (1) first and second handle members, the first handle member being fixed to the proximal end of the first shaft, and the second handle member being pivotally mounted to the first handle, (2) a rack and gear means connecting the second handle member and the second shaft so that when the handles are moved relative to one another in a first direction, the jaws attached to the first shaft will be squeezed into clamping relation with tissue or other matter in a collet-like manner by the action of the second shaft moving in a first direction relative to the first shaft, and (3) means for urging the second shaft to move in a direction to return the jaws to open position. The handle mechanism is arranged so that it may be held and operated in either a pistol-grip or a scissors-type mode. In a preferred embodiment, the novel handle mechanism is characterized by a ratchet-type locking mechanism for automatically locking the two handle members in gripping engagement with tissue or other objects (even if the surgeon accidentally or deliberately loses control of the instrument), and means for releasing the locking mechanism so that the two handle members are free to open and release the grasped tissue or other object.

In still another embodiment, the instrument is provided with a reversing gear for reversing the effect of movement of the two handle members on the two jaws.

Other features and advantages of the invention are illustrated in the accompanying drawings and/or described or rendered obvious by the following specific description of preferred and alternative embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary left-hand side view in elevation of a grasper constituting a preferred embodiment of the invention, showing the jaws completely closed and correspondingly the handle members squeezed together as far as possible;

FIG. 2 is a plan view of the instrument of FIG. 1;

FIG. 3 is a bottom view of the instrument of FIG. 1;

FIGS. 4 and 5 are front and rear elevational views of the same instrument;

FIG. 6 is a view like FIG. 1 showing the jaws in fully open position;

FIG. 7 is a longitudinal sectional view in side elevation of the tip (or jaw end) portion of the same tool, except that the jaws are shown incompletely closed, contact between them having just been initiated at the remote outermost end of the jaws;

FIG. 8 is a longitudinal sectional view in side elevation, similar to FIG. 1, except that the jaws are shown fully open;

FIG. 9 is a partially exploded, fragmentary sectional view in side elevation illustrating the ratchet-type locking mechanism provided according to the present invention, and also showing the connector used to electrify the instrument;

FIG. 10 is a plan view, partially in section, of a portion of the locking mechanism sub-assembly;

FIGS. 11 and 12 are fragmentary side elevations showing two alternative positions of the locking mechanism;

FIG. 13 is a longitudinal sectional view in side elevation of a modification of the tool incorporating electrical insulation means for preventing capacitively-coupled electrical energy from being transmitted to the patient;

FIG. 14 is a front view of the structure shown in FIG. 13;

FIG. 15 illustrates another form of the invention and constitutes a fragmentary sectional view in side elevation of the handle portion of an instrument having bipolar cauterization capability;

FIG. 16 is an enlarged fragmentary sectional view in side elevation showing the front end of the bipolar cauterization instrument of FIG. 15;

FIG. 17 is a fragmentary plan view of one of the jaw members of the embodiment of FIGS. 15 and 16;

FIG. 18 is a bottom view of the other jaw member of FIG. 16;

FIG. 19 is an exploded view illustrating components of the front end of the same instrument;

FIG. 20 is a fragmentary side elevation, partially in section, illustrating another embodiment of the invention involving a reversing gear;

FIG. 21 is a longitudinal sectional view in elevation of a form of scissors-type head that may be combined with a handle mechanism provided by the present invention;

FIG. 22 illustrates a further embodiment of the invention adapted for use with the head of FIG. 21;

FIG. 23 is a view of a modification of the invention designed to provide an irrigation and cleaning function; and

FIG. 24 is an enlarged cross-sectional view taken through the center of the irrigation adapter of FIG. 23.

In the drawings, like numerals identify like elements of construction.

PREFERRED EMBODIMENT OF THE INVENTION

As noted hereinabove, surgical instruments employing movable jaws and mechanisms for moving the jaws typically involve coaxial telescoping elements in the form of a hollow outer shaft and an inner shaft which may be hollow or take the form of a solid rod. Additionally, the various jaw mechanisms typically used in surgical instruments require or use one of two different combinations of motion for opening and closing the tissue-engaging elements or jaws. Those two combinations of motion are as follows: (1) reciprocating the outer shaft relative to the inner shaft, with the latter being fixed against movement relative to the handle mechanism; and (2) reciprocating the inner shaft relative to the outer shaft, with the latter being fixed against movement relative to the handle mechanism. It is also recognized as possible to design a system in which both the outer and inner shafts may move at the same time. However, since it is the relative motion between the inner and outer shafts that is material, any combination resulting in a differential movement, either additive or subtractive, would provide a net effect that is not qualitatively different than the two reciprocal motions described above.

The present invention is concerned with providing surgical instruments of the type described with handle mechanisms designed specifically to have any one of four reciprocal motions as follows: (1) the inner shaft is fixed to the handle unit and the outer shaft is coupled to a movable driver means on the handle unit, with closing operation of the handle unit involving forward telescoping movement of the outer shaft by the driver means; (2) the inner shaft is fixed to the handle unit and the driver means includes a reversing gear mechanism coupled to the outer shaft, whereby closing operation of the handle unit is characterized by rearward telescoping movement of the outer shaft; (3) the outer shaft is fixed to the handle unit, and the inner shaft is coupled to a movable driver means on the handle unit, with closing operation of the handle unit involving forward telescoping movement of the inner shaft by the driver means; and (4) the outer shaft is fixed to the handle unit, and the driver means in the handle unit includes a reversing-gear mechanism, whereby closing operation of the handle unit is characterized by rearward telescoping movement of the inner shaft relative to the outer shaft.

Notwithstanding the fact that the mechanical arrangement presently preferred in the industry for graspers and the like is to have a tool wherein the outer shaft is fixed to the handle mechanism and the inner shaft moves telescopically relative to the outer shaft, the preferred embodiment of the invention involves a handle mechanism that is capable of moving the outer shaft forwardly and rearwardly relative to the inner shaft to effect closing and opening respectively of the jaws. However, in contemplation of providing multipurpose instruments, modifications of the invention are disclosed which including fixing the outer shaft and moving the inner shaft relative to the outer shaft, and/or providing a reversing gear whereby movement of the handle members will provide opposite relative movement of the inner and outer shafts. The latter modification is significant in that many types of jaw mechanisms require or may be improved by utilizing a reverse kinematic relationship of the handle mechanism and the members coupled thereto. Referring now to FIGS. 1-9, the instrument shown therein includes unitary jaw piece 2 divided at its front end into two or more jaws 4 and 6, an outer hollow shaft 8, inside of which resides an inner shaft 10 (FIG. 7), a handle assembly identified generally by numeral 12, and a stationary housing 34. Inner shaft 10 may be a solid rod, but preferably it is a hollow shaft as shown in FIG. 7. Handle assembly 12 includes a stationary handle member 16 and a movable handle member 14 that is rotatable with respect to stationary handle member 16 about a pivot pin or rod 18 (FIG. 9). Handle member 16 is formed integral with and forms an extension of housing 34. Operation of the handle members is facilitated by finger loops 20 and 22 on handle members 14 and 16.

As seen best in FIGS. 7-9, jaw piece 2 is affixed to and spaced from housing 34 by inner shaft 10, such as by welding the rear end face 23 of jaw piece 2 to the front end of shaft 10.

Outer shaft 8, which coaxially surrounds and is free to slide axially relative to inner tube 10, is rigidly joined to a gear rack tube or sleeve 36, e.g., by a press fit, a cement, welding or a pin. Outer shaft 8 and gear rack tube 36 slide freely relative to inner shaft 10. Gear rack sleeve 36 is formed with a rear bore 39 sized to make a close sliding fit with inner shaft 10, a first counterbore 41 sized to snugly receive the proximal (rear) end of outer shaft 8, and a second counterbore 43 that receives a compression spring 45 that surrounds outer shaft 8. The forward end of spring 45 engages the adjacent forward end wall of gear rack tube chamber 42 (hereinafter described) and thereby acts to urge gear sleeve 36 to move rearwardly in that chamber. Tube 36 is formed with a rack or set of gear teeth 40 spaced along its length in a straight line. An O ring 47 is disposed in gear rack tube 36 between its inner end wall and the inner end of outer shaft 8. The O-ring surrounds and grips inner shaft 10 and acts as a sliding seal to prevent body fluids from travelling from the jaw piece 2 between shafts 8 and 10 into the handle housing 34, from which the fluids could escape to the surrounding environment.

Housing 34 is formed in two mating parts 34A and 34B (FIG. 2, 3, 5 and 9) and stationary handle member 16 is formed from two like integral extensions 16A and 16B of housing parts 34A and 34B respectively. The rear ends of housing parts 34A and 34B are formed with rearwardly projecting sections 17A, 17B that combine to form a tang 17 that is shaped so that its rear surface forms a smoothly curved extension of the rear surface of fixed handle member 16, whereby the fixed handle is contoured similarly to that of a 45 cal. Colt automatic pistol. The tang embraces and anchors the web of the hand (i.e., the portion of the hand extending between the thumb and the forefinger) that may be gripping the instrument, permitting the fixed handle to nest comfortably in the user's hand. Housing parts 34A, 34B, including handle portions 16A, 16b, are secured to one another in a conventional way depending on the material of which they are made, e.g., by ultrasonic welding or cementing in the case of plastic and by removable fasteners in the case of metal. For this purpose, and as shown in FIG. 9 which presents a side elevation of the inner side of the right hand housing half 34B, molded energy director strips 35 are provided to facilitate ultrasonic welding (assuming that the handle parts are made of a suitable plastic material such as a polycarbonate). To facilitate assembly, a plurality of registration pins, two of which are shown at 37, are provided in housing part 34B, for insertion into correspondingly located shallow blind registration holes (not shown) in housing part 34A.

Housing 34 has an elongate cylindrical gear tube chamber 42 formed by elongate matching semi-cylindrical recesses 42 in housing parts 34A and 34B (note that FIG. 9 shows only the right hand half 34B of the handle housing). For convenience of illustration and description, the matching recesses or cavities in handle housing halves 34A, 34B, and the chambers or bores formed by such recesses or cavities, are identified by the same numerals, e.g., recesses 42 form chamber 42. Housing parts 34A and 34B also have aligned semi-cylindrical cavities 30 that combine to form an elongate bore in which the rear or proximal end of inner shaft 10 is secured, e.g., by a press fit, cementing or other interlocking means such as a pin as shown at 49. Forwardly of gear tube chamber 42 the housing parts 34A and 34B have aligned semi-cylindrical recesses 44 that combine to form a counterbore that is coaxial with and intersects chamber 42 and has a diameter just large enough to allow shaft 8 to make a close sliding fit therein. Gear rack tube 36 is sized to make a close sliding fit in chamber 42, and has a substantially shorter length than that of chamber 42 so as to allow it to be reciprocated between the two limit positions shown in full and dotted lines in FIG. 9. The two housing parts 34A and 34B have matching recesses 46 (FIG. 9) which form a slot that intersects the gear rack tube chamber 42 at the six o'clock position, so as to provide an axially elongate opening to accommodate handle member 14 between the forward sections of the two fixed handle parts 16A, 16B. Preferably pivot pin 18 is a cylindrical projection that is molded as an integral part of one of the two housing parts 34A, 34B and seats in a cavity located in the opposite housing part. However, pivot pin 18 may take the form of a separate threaded pivot pin that passes through aligned holes in the two housing parts and handle member 14, with a nut or other means (not shown) h