# Patent

## Title
Surgical instrument for joining tissue

## Abstract

A surgical instrument for surgically joining tissue is provided. The surgical instrument includes a handle assembly that includes an actuator member. An end effector is operatively disposed adjacent a distal portion of an elongated shaft of the surgical instrument. The end effector includes a first jaw member pivotably disposed with respect to a second jaw member. The end effector is movable between a first position where the jaw members are spaced from one another, and a second position where the jaw members are in an approximated position. Each of the first and second jaw members includes a respective longitudinal track. An actuation assembly is disposed in mechanical cooperation with the end effector, wherein actuation of the actuation member causes the actuation assembly to translate from a distal portion of the end effector towards a proximal portion of the end effector through the tracks in the first and second jaw members.

## Background
BACKGROUND
1. Technical field
This application relates to surgical instruments for joining tissue, and more particularly, to surgical instruments that are pull activated for sequentially applying a plurality of surgical fasteners to body tissue and to electrosurgical instruments that are configured to sever tissue after tissue has been electrosurgically treated.
2. Background of Related Art
Surgical instruments wherein tissue is first grasped or clamped between opposing jaw structure and then joined by surgical fasteners, or other suitable means, are well known in the art. Instruments for this purpose can include two elongated members which are respectively used to capture or clamp tissue. Typically, such surgical instruments include a shaft extending from a handle and/or trigger assembly, an end effector assembly, which includes an anvil assembly and a cartridge assembly for supporting a plurality of surgical fasteners, an approximation mechanism for approximating the anvil and cartridge and anvil assemblies, and an actuation assembly for ejecting the surgical fasteners from the cartridge assembly. In some instances, the surgical instrument may be adapted to connect to a loading unit (e.g., disposable loading unit) that includes an end effector assembly, which includes an anvil assembly and a cartridge assembly for supporting a plurality of surgical fasteners. Typically, the actuation assembly is operatively coupled to a sled, cam or wedge in operative mechanical communication with the cartridge assembly. During a firing sequence of the surgical instruments, the sled is translated into contact with a pusher associated with a surgical fastener causing the surgical fastener to eject from the cartridge assembly and into the anvil assembly such that a surgical fastener line may be formed within tissue.
Electrosurgical instruments (e.g., electrosurgical forceps) are well known in the medical arts and can include a handle, a shaft and an end effector assembly, which includes jaw members operatively coupled to a distal end of the shaft, that is configured to manipulate tissue (e.g., grasp and seal tissue). Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize, seal, cut, desiccate, and/or fulgurate tissue. The electrosurgical forceps may include a knife blade or cutter which may be configured to translate within a knife channel or slot operatively associated with one or both of the jaw members such that after the tissue has been electrosurgically treated (e.g., sealed), tissue may be effectively severed.
In some instances, it may prove advantageous to bend or articulate the shaft of the surgical instruments (e.g., during a lower anterior resection “LAR” procedure) and/or the electrosurgical forceps (e.g., during an electrosurgical tissue sealing procedure). When the shaft of the surgical instruments is bent or articulated, there may exist practical challenges associated with a translation force required to translate the sled along the shaft during the firing sequence. Likewise, when the shaft of the electrosurgical forceps is bent or articulated, there may exist practical challenges associated with a translation force required to translate the knife blade within the knife slot after tissue has been electrosurgically treated. When the shaft of the surgical fastener applying instrument is articulated, a force is required to close the anvil assembly and cartridge assembly onto tissue, translate a knife and/or fire or deploy the surgical fastener.
SUMMARY
According to an aspect of the present disclosure, a surgical instrument configured to surgically join tissue is provided. The surgical instrument includes a handle assembly with an actuation member. The surgical instrument includes an elongated portion that extends distally from the handle assembly and defines a longitudinal axis. An end effector is operatively disposed adjacent a distal portion of the elongated portion. The end effector includes a first jaw member pivotably disposed with respect to a second jaw member. The end effector is movable between a first position where the jaw members are spaced from one another, and a second position where the jaw members are in an approximated position. Each of the first and second jaw members includes a respective longitudinal track. An actuation assembly is disposed in mechanical cooperation with the end effector, wherein actuation of the actuation member causes the actuation assembly to translate from a distal portion of the end effector towards a proximal portion of the end effector through the tracks in the first and second jaw members.
The instrument may have an end effector with a cartridge assembly and an anvil assembly. In certain embodiments, the proximal movement of the actuation assembly causes staples to be ejected from the cartridge assembly toward the anvil. The actuation assembly can have cam with a knife, the knife including a proximal edge configured to sever tissue.
A top and a bottom of the cam forms an I-beam shape in certain embodiments. The top and bottom portions of the cam are receivable in tracks in the first jaw member and second jaw member. The end effector can have a cam pin and a cam slot for approximating the first and second jaw members. The distal portion of the second jaw member is configured to house at least a portion of the actuation assembly prior to actuation of the actuation member.
In certain embodiments, the instrument includes an actuation cable in mechanical cooperation with the actuation assembly and with the actuation member. An approximation member can be provided in cooperation with the handle assembly for causing distal translation of an approximation assembly which causes the end effector to move toward the second position.
In certain preferred embodiments, the end effector articulates with respect to the longitudinal axis of the instrument. The end effector may form part of a loading unit that can be removable and replaceable.
In certain embodiments, at least one of the jaw members is pivotable about a pivot point. The surgical instrument can be configured for use in minimally invasive or laparoscopic surgery.
According to an aspect of the present disclosure a loading unit configured for use with a surgical instrument is provided. The loading unit includes a proximal end that is configured to connect to a distal end of the surgical instrument. A distal end includes an end effector having a first jaw member pivotably disposed with respect to a second jaw member. The end effector is movable between a first position where the jaw members are spaced from one another, and a second position where the jaw members are in an approximated position. Each of the first and second jaw members includes a respective longitudinal track. An actuation assembly is disposed in mechanical cooperation with the end effector, wherein actuation of the actuation member causes the actuation assembly to translate from a distal portion of the end effector towards a proximal portion of the end effector through the tracks in the first and second jaw members.
According to another aspect of the present disclosure a surgical stapling instrument is provided. The surgical stapling instrument includes a handle assembly having an actuator member. An elongated shaft extends distally from the handle assembly and defines a longitudinal axis. An end effector is operably disposed at a distal end of the shaft and has a first jaw member with a first distal, free end and a second jaw member with a second distal, free end. One or both of the first jaw member and second jaw member is pivotably movable about a pivot portion at a proximal portion of the jaw members. An actuation head at the first distal, free end of the first jaw member is connected to a flexible actuation member. In one particular embodiment, the first jaw member is a surgical stapling cartridge. A locking feature is operably disposed at the first distal free end of the first jaw member and is configured to maintain the first and second jaw members in a substantially fixed position.
A surgical instrument according to the present disclosure can have a second jaw member which is an anvil assembly.
Proximal movement of the actuation head causes staples to be ejected from the cartridge assembly towards the anvil assembly. The actuation head can include a knife with a proximal edge configured to sever tissue.
In certain embodiments, a top and bottom portion of the actuation head forms an “I” beam configuration, such that the top and bottom portions of the actuation head are receivable within respective tracks associated with the first and second jaw members.
A cam slot and cam pin configuration, in certain embodiments, is operably associated with the end effector and configured to facilitate remote approximation of the first and second jaw members.
The cam slot can be disposed in parallel relation with respect to a proximal end of at least one of the jaw members. The first distal, free end of the first jaw member may be configured to house at least a portion of the actuation head prior to actuation of the actuator member. An approximation member disposed in mechanical cooperation with the handle assembly, wherein actuation of the approximation member causes distal translation of an approximation assembly which causes the end effector to move towards its second position.
The end effector defines a second longitudinal axis and the end effector is desirably movable between a parallel position where the first longitudinal axis is substantially parallel to the second longitudinal axis and an offset position where the first longitudinal axis and the second longitudinal axis are offset from each other.



BRIEF DESCRIPTION OF THE DRAWINGS
Various embodiments of the present disclosure are described herein with reference to the drawings wherein:
FIG. 1A is a perspective view of a surgical stapling instrument including a loading unit adapted for use with an actuation assembly for sequentially firing a plurality of surgical fasteners in accordance with an embodiment of the present disclosure;
FIG. 1B is a perspective view of an open surgical stapling instrument intended for use with an actuation assembly for sequentially firing a plurality of surgical fasteners in accordance with another embodiment of the present disclosure;
FIG. 1C is a perspective view of an endoscopic electrosurgical forceps intended for use with an actuation assembly in accordance with another embodiment of the present disclosure;
FIGS. 2A-2C are side views in partial phantom of a distal portion of the loading unit depicted in FIG. 1A;
FIG. 3A is a perspective view illustrating a mechanical interface that is utilized to couple a proximal end of the loading unit to the surgical instrument in accordance with an embodiment of the present disclosure;
FIG. 3B is a side view of the proximal end of the loading unit coupled to the surgical instrument with the proximal end shown in a locked configuration;
FIG. 3C is a partial cross-sectional view of the proximal end of the loading unit coupled to the surgical instrument with the proximal end shown in an un-locked configuration;
FIG. 4A is is a perspective view illustrating a mechanical interface that is utilized to couple a proximal end of the loading unit to the surgical instrument in accordance with an alternate embodiment of the present disclosure;
FIG. 4B is a side view of the proximal end of the loading unit depicted in FIG. 4A coupled to the surgical instrument with the proximal end shown in a locked configuration;
FIG. 5 is a side view in partial phantom of an alternate configuration of an end effector adapted for use with the loading unit depicted in FIGS. 2A-2C;
FIG. 6 is a perspective view of a surgical stapling instrument including a loading unit adapted for use with an actuation assembly for sequentially firing a plurality of surgical fasteners in accordance with an embodiment of the present disclosure;
FIGS. 7A-7B are side views in partial phantom of a distal portion of the loading unit depicted in FIG. 4;
FIG. 8 is a perspective view of a surgical stapling instrument including a loading unit adapted for use with an actuation assembly for sequentially firing a plurality of surgical fasteners in accordance with an embodiment of the present disclosure;
FIG. 9A is a side view in partial phantom of a distal portion of the loading unit depicted in FIG. 6 positioned within an access port and in a non-approximated configuration;
FIG. 9B is a side view in partial phantom of the distal portion of the tool assembly depicted in FIG. 6;
FIG. 10 is a perspective view of a distal portion of a surgical stapling instrument in accordance with an embodiment of the present disclosure.
FIG. 11 is a partial cross-sectional view of an end effector for a surgical stapling instrument in accordance with certain aspects of the present disclosure.



DETAILED DESCRIPTION
Embodiments of the presently disclosed surgical instrument are described in detail with reference to the drawings, wherein like reference numerals designate similar or identical elements in each of the several views. In the drawings and the description that follows, the term “proximal” refers to the end of the surgical stapling instrument that is closest to the handle assembly, whereas the term “distal” refers to the end of the surgical stapling instrument that is farthest from the handle assembly. As appreciated by one skilled in the art, the depicted surgical stapling instrument fires staples, but it may be adapted to fire any other suitable fastener such as clips and two-part fasteners.
FIG. 1A illustrates one type of surgical stapling instrument that may be employed with an actuation assembly 100 (FIG. 2A-2C) of the present disclosure. Briefly, surgical stapling instrument 10 includes a handle assembly 12 and an elongated body or shaft 14. Shaft 14 defines a longitudinal axis X-X. Shaft 14 may be substantially rigid, or in some instances shaft 14 may flexible and capable of bending, articulating, or pivoting (shown in phantom). Handle assembly 12 includes a stationary handle member 16, and a movable handle member 18. A rotatable member 20 is mounted on the handle assembly 12 to facilitate rotation of elongated body 14 with respect to handle assembly 12. An articulation lever 22 is also mounted on handle assembly 12 to facilitate articulation of an end effector 24. The distal end of instrument 10 may be configured as a loading unit 26 (e.g., a disposable loading unit (DLU) or a single use loading unit (SULU)) that is releasably secured to a distal end of shaft 14. Loading unit 26 includes end effector 24 including a pair of pivotably coupled opposing first and second jaw members 30a and 28a, respectively, including a respective anvil assembly 30 having a plurality of staple forming pockets and cartridge assembly 28 housing a plurality of surgical staples. The first jaw member and cartridge assembly has a first distal, free end and the second jaw member has a second distal, free end. The jaw members are pivotably movable about a pivot portion at a proximal portion of the jaw members. In embodiments, one or both of the cartridge assembly 28 and anvil assembly 30 may be configured to conduct electrosurgical energy.
For a more detailed description of the operation of surgical stapling instrument 10 reference is made to commonly-assigned U.S. Pat. No. 5,865,361 to Milliman et al. and U.S. Pat. No. 5,762,256 to Mastri et al., which are each incorporated herein by reference in their entirety.
Actuation assembly 100 may be adapted for use with an open surgical stapling instrument 300 (FIG. 1B) that is configured for use during an open gastro-intestinal anastomotic stapling procedure or, for example, any of the surgical fastener-applying apparatus discussed in U.S. Pat. Nos. 6,045,560; 5,964,394; 5,894,979; 5,878,937; 5,915,616; 5,836,503; 5,862,972; 5,817,109; 5,797,538; and 5,782,396, which are each incorporated by reference herein in their entirety.
Actuation assembly 100 may be adapted for use with an electrosurgical instrument 500, e.g., an endoscopic electrosurgical forceps 500 (FIG. 1C). Briefly, the electrosurgical instrument 500 can be any suitable type of electrosurgical instrument, including but not limited to electrosurgical instruments that can grasp and/or perform any of the above mentioned electrosurgical procedures. One type of electrosurgical instrument may include an endoscopic electrosurgical forceps 500 as disclosed in United States Patent Publication No. 2007/0173814 entitled “Vessel Sealer and Divider for Large Tissue Structures,” which is incorporated by reference herein in its entirety. A brief discussion of endoscopic electrosurgical forceps 500 and components, parts, and members associated therewith is included herein to provide further detail and to aid in the understanding of the present disclosure.
Electrosurgical forceps 500 is shown for use with various electrosurgical procedures (e.g., tissue sealing procedure) and generally includes a housing 520, a handle assembly 530 that includes a movable handle 540 and a fixed handle 550, a rotating assembly 580, a push button assembly 560, a trigger assembly 570, a shaft 512, and an end effector assembly 600, which mutually cooperate to grasp, seal and divide large tubular vessels and large vascular tissues. In embodiments, electrosurgical forceps 500 is adapted to connect to an electrosurgical energy source 700. Although the majority of the figure drawings depict an electrosurgical forceps 500 for use in connection with laparoscopic surgical procedures, the present disclosure may be used for more traditional open surgical procedures or endoscopic procedures.
For the purposes of brevity, the functional and operational features of actuation assembly 100 will be described in terms of use with surgical stapling instrument 10.
Referring now to FIGS. 2A-2C, and initially with reference to FIG. 2A an embodiment of the actuation assembly 100 for sequentially applying the fasteners of device 10 is shown. In the embodiment illustrated in FIGS. 2A-2C, a proximal end 27 of a loading unit 26 is configured to releasably secure to a distal end of the elongated shaft 14 (see FIG. 1A in combination with FIGS. 3A-3C. The loading unit 26 includes a proximal body and an effector and may be a disposable or replaceable loading unit. Alternatively, a removable cartridge assembly can be used and the cartridge assembly may be replaced after the cartridge assembly is fired.
Actuation assembly 100 may include or be in operative communication with an actuator or trigger member (e.g., movable handle 18) configured such that actuation thereof produces a pulling force that drives a actuation head 104 associated with the actuation assembly 100 proximally causing a plurality of the staples associated with a cartridge assembly 28 to deploy from the cartridge assembly 28. In certain embodiments, the actuation head 104 is disposed at the distal, free end of the first jaw member and cartridge assembly. One such actuator member is disclosed in commonly-assigned U.S. Pat. No. 7,296,724 to Green et al., the entire contents of which is incorporated herein by reference. Loading unit 26, the distal end of elongated shaft 12 and/or any other parts or components associated with device 10 may include any number of gears, screws, pins, cams, links, pulleys, springs, spools, additional conduits, and/or other suitable mechanical/electrical components and/or systems such that the actuation assembly 100 can function in a manner as described herein.
In one particular embodiment, a cable 19 is operably coupled to the movable handle 18 and is configured such that proximal movement of the movable handle 18 causes the cable 19 to move proximally within the shaft 12, which, in turn causes the actuation head 104 to move proximally within the cartridge assembly 28 such that the plurality of the staples associated with a cartridge assembly 28 deploy from the cartridge assembly 28. More particularly, a coupling or locking structure 21 is operably associated with the cable 19 and is configured to matingly and releasably engage a corresponding structure, e.g., a plug 105, associated with an actuation member 102. To this end, locking structure 21 is suitably proportioned to releasably couple to the actuation member 102. More particularly, locking structure 21 includes a generally elongated configuration having a generally circumferential shape, as best seen in FIG. 3A. A proximal end of the locking structure 21 is operably coupled to the cable 19 by one or more suitable coupling methods, e.g., adhesive. A distal end of 23 of the locking structure 21 matingly and releasably secures to the actuation member 102. With this purpose in mind, distal end 23 includes a pair of locking surfaces in the form of a pair of locking tabs 25 that collectively define a pair of lateral slots or notches 29 dimensioned to receive a portion, e.g., plug 105, of the actuation member 102. A cavity 31 of suitable dimension is defined by the locking structure 21 and is disposed between the locking tabs 25 and the proximal end of the locking structure 21. The cavity 31 of the locking structure 21 is dimensioned such that when the plug 105 is positioned within the cavity 31, the plug 105 is movable therein to engage the locking tabs 25. More particularly, after the plug is positioned within the cavity 31 (see FIG. 3C, for example), the loading unit 26 may be rotated such that the plug 105 and locking tabs 25 are in engaged alignment with one another, see FIG. 3B, for example.
With reference to FIGS. 4A and 4B an alternate embodiment of the locking structure is shown designated 121. Locking structure 121 depicted in FIGS. 4A and 4B, is substantially similar to locking structure 21. Locking structure 121 includes a pair of locking surfaces in the form of a pair of locking tabs 125 (FIG. 4B). In FIGS. 4A and 4B, the locking structure 121 includes a single notch 133 that is dimensioned to receive the plug 105 of the actuation member 102 when the loading unit 26 is being attached to the surgical instrument 10, see FIG. 4A, for example. As described above with respect to locking structure 21, once the plug 105 is positioned within the cavity 131, the loading unit 26 may be rotated such that the plug 105 and locking tabs 125 are in engaged alignment with one another, see FIG. 4B, for example.
As can be appreciated by those skilled in the art, other mechanical interface configurations may be utilized to operably couple the cable 19 of the surgical instrument 10 to the actuation member 102 of the loading unit 26.
With reference to FIGS. 1A and 2A, actuation member 102 is shown. Actuation member 102 may be any suitable type of actuation member known in the art including, but not limited to cable, wire, chain, spring (e.g., constant force tension spring such as the one sold by AMETEK® under the trademark NEG'ATOR®) or combination thereof. The actuation member is desirably flexible. In the embodiment illustrated in FIGS. 2A-2C, actuation member 102 is in the form of a flexible cable 102. Cable 102 is configured to stretch, bend and/or articulate when the shaft 14 is in a bent and/or articulated position. Cable 102 may be made from any suitable material. In embodiments, cable 102 may be formed from or coated with a material that is relatively lubricious (e.g., PTFE) such that the coefficient of static and/or kinetic frictions between the cable 102 and other operative components associated with device 10 are kept to a minimum. In an embodiment, cable 102 operatively couples the movable handle 18 to an actuation head 104 that is operatively associated with the end effector 24, to be discussed in more detail below. In the embodiment illustrated in FIGS. 2A-2C, cable 102, or portion thereof, is operatively housed and movable within loading unit 26. Cable 102 extends from a proximal end of loading unit 26 (shown in FIGS. 1A and 3A and 3B) to a distal end 34 of the end effector 24 (FIG. 2A) via an opening (not shown) operatively disposed at a proximal end of end effector 24, cartridge 28, and/or anvil 30. Cable 102 may be configured to translate within a guide, channel or groove operatively disposed within cartridge 18 to facilitate movement of cable 102 within cartridge 18.
In the illustrated embodiments, a proximal end 103 of the cable 102 adjacent the proximal end 27 of the loading unit 26 is configured to couple to a distal end of the shaft of the surgical instrument 10 via one or more of the mechanical interfaces described above, e.g., plug 105 and locking structure 21 or 121. For illustrative purposes, plug 105 is described in terms of use with locking structure 21. As noted above, plug 105 is configured to matingly engage the locking tabs 25 (or in some instances locking tabs 125) of the locking structure 21, see FIG. 3B, for example. A distal end of the plug 105 is operably coupled to the cable 102 by one or more suitable coupling methods, such as, for example, the coupling method utilized to couple the proximal end of the locking structure 21 to the cable 19. Plug 105 includes one or more surfaces that are configured to engage the locking tabs 25. More particularly, plug 105 includes a pair trailing surfaces 107 configured to engage a respective one of the locking tabs 25 (or in some instances locking tabs 125) when the plug 105 is positioned with the cavity 31 and the plug 105 and/or loading unit 26 is rotated from an unlocked position (see FIG. 3C, for example) to the locked position (see FIG. 3B, for example).
A handle assembly with an actuator member that may be used to retract the cable 102 is disclosed in U.S. Pat. No. 5,897,562 to Bolanos et al., the disclosure of which is hereby incorporated by reference herein in its entirety. One or more spools are ratcheted to draw the cable 102 around the one or more spools and retract the cable 102. Detents or pawls are used so that multiple actuations of the trigger handle will wind the cable 102 around the spool.
Actuation assembly 100 includes one or more actuation heads 104 that is operatively associated with the cartridge 28 and disposed at distal end 34 of the end effector 24 (see FIG. 2A, for example). Actuation head 104 is translatable within cartridge 28 from distal end 34 of the end effector 24 to at least a proximal end 36 of the cartridge. To this end, actuation head 104 may include any suitable configuration. In the embodiment illustrated FIGS. 2A-2C, actuation head 104 includes an “I” beam shaped configuration. In addition, a proximal or leading edge 104a (FIG. 2A) of actuation head 104, or portion thereof, is incorporated therein. Leading edge 104a is configured to contact a plurality of pushers 106b operatively disposed within cartridge 28 so that during a firing sequence of the instrument 10 a corresponding plurality of staples 106a are caused to be ejected from the cartridge 28 (FIG. 2C) towards anvil 30. For example, the leading edge 104a may be configured as a wedge or cam. A proximal end of the actuation head 104 operably couples (via adhesive, solder, etc.) to cable 102 (FIG. 2A). A bottom portion 104b of actuation head 104 is translatable within a longitudinal track 120 (e.g., a slot corresponding to the bottom flange of the I-beam) operably associated with the second jaw member 28a and extending substantially along a length of the cartridge 28 (see FIG. 2A, for example). A top portion 104c of actuation head 104 is receivable within a longitudinal track 112 operatively associated with first jaw member 30a and extending substantially along a length thereof. In an embodiment, top portion 104c of actuation head 104 forms a top portion of the “I” beam structure and includes a compression member in the form of a lip or flange 108b that is configured to compress the anvil 30 and cartridge 28 together during the firing sequence.
A knife blade or cutter 108 is operatively connected (via adhesive, solder, etc.) to actuation head 104. Alternatively, knife blade 108 and actuation head 104 may be a unitary structure manufactured by known techniques (e.g., molded, over-molded, etc.) Knife blade 108 is disposed within cartridge 28 at the distal end 34 of the end effector 24. Knife blade 108 includes a leading or proximal edge 108a (FIG. 2A) that is spaced distally relative to the proximal edge 104a of actuation head 104 and includes a generally arcuate or concave configuration. In an alternate embodiment, proximal edge 108a may be flat. In this embodiment, proximal edge 104a of actuation head 104 may be elongated and extend proximally relative to the proximal edge 108a of the knife blade 108. Knife blade 108 is oriented in a substantially perpendicular relation to a longitudinal axis X that extends along the length of device 10 and loading unit 26. Knife blade 108 is translatable from the distal end 34 of the end effector 24 to at least the proximal end 36 of cartridge 28 within a knife channel 32 operatively disposed along a length of cartridge 28 (an example of which is shown in FIG. 1A).
One or more camming features 110 are operatively disposed on end effector 24. In the embodiment illustrated in FIGS. 2A-2C, camming feature 110 may be employed when manual approximation of the cartridge 28 and anvil 30 is required. That is, the movable handle 18 is not configured to approximate the anvil 30 and cartridge 28 toward each other. To this end, a camming feature 110 is operably positioned on both a right and left side of the end effector 24 (see FIG. 1A in combination with FIGS. 2A-2C). The camming feature 110 on each of the right and left sides of the end effector 24 is identical, thus, and unless otherwise noted, the operative and functional features of each of the camming features 110 will be described in terms of a left camming feature 110. A cam pin 114 is operably associated with the end effector 24 adjacent the cartridge 28 and operatively connects to a cam slot 126 disposed on anvil 30. The cam pin 114 and cam slot 126 may be configured in any suitable configuration. In the embodiment illustrated in FIGS. 2A-2C, the cam slot 126 is obliquely orientated with respect to the X axis and parallel with respect to a proximal portion of the first jaw member 30a, see FIGS. 2B and 2C, for example. In an alternate embodiment, the cam slot 126 is orthogonally oriented with respect to the X axis and parallel with respect to a proximal portion of the first jaw member 30a, as best seen in FIG. 5. In either arrangement, the camming configuration is intended to aid a clinician in approximating the anvil 30 and cartridge 28 toward each other. That is, this camming configuration provides an additional mechanical advantage for overcoming the high forces associated with the clamping down of tissue between the anvil 30 and cartridge 28.
In an embodiment, end effector 24 may include one or more types of locking features configured to maintain the anvil 30 and cartridge 28 in an approximated position. The locking feature(s) may be any suitable locking feature(s) known in the art. In certain embodiments, the locking feature is provided at the distal, free end of the cartridge assembly to engage the anvil. For example, in the embodiment illustrated in FIGS. 2A-2C, a distal end 38 of the anvil 30 is configured to engage the distal end 34 of the end effector 24 and/or cartridge 28. More particularly, the distal end 38 of the anvil 30 includes a generally curved or arcuate end configured to selectively and releasably engage an opening or recess 40 associated with the distal end 34 of the end effector 24 (see FIG. 1A in conjunction with either of FIG. 2A or 2C, for example). In the embodiment illustrated in FIGS. 2A-2C, a protrusion 42 is operably disposed within the opening 40 and extends at an angle relative to the axis X toward the distal end 34 of the end effector 24. The protrusion 42 is configured to selectively and releasably engage the arcuate surface 38 of the anvil 30 such that anvil 30 is maintained in a substantially fixed position when the anvil 30 is engaged with the opening 40. To facilitate engagement of the anvil 30 within the opening 40 the protrusion 42 may be biased radially inward. In this instance, the protrusion 42 may be formed from a resilient material, or may be operably associated with a spring (not shown). Other locking features are contemplated herein, such as detents, latches, clips, etc. The anvil 30 has a slot for accommodating the actuation head 104 as the anvil 30 is moved toward the cartridge assembly 28. In certain preferred embodiments, the distal end 234 of the end effector 224 or the jaw opposite the anvil 230 has an inwardly biased (i.e., biased generally in the proximal direction) lock member 231 for securely engaging the anvil 230 (see FIG. 11). The lock member has a recess shaped to securely engage the distal end of the anvil 230 and prevent movement of the anvil 230 or, alternatively, the distal end of the anvil 230 has a recess and the lock member has a protrusion engaged by the recess. The lock member has a first position securing the anvil 230 in place and a second position allowing the anvil to move away from the opposing jaw and allowing the end effector to open and release tissue. In certain preferred embodiments, the lock member is attached to a pusher that extends to handle assembly. The pusher 233 may be attached to a button or other manipulatable member allowing the user of the instrument to release the anvil 230 after the staples have been deployed. Thus, for relatively thick tissue, the second jaw member 228 has a distal end extending transversely to the longitudinal axis, enclosing the gap between the first and second jaw member 228. The first jaw member 30a locks into the second jaw member 228, capturing tissue between the jaws so that relatively thick tissue will not escape the gap between the jaws. The user may release lock, and open the jaws by manipulating the manipulatable member, moving the lock member holding the anvil 230 in place in the closed position. After releasing the lock member, the anvil 230 can be moved to an open position. It is contemplated that the anvil have more than one closed position and that the lock fix the anvil in a first, second, or third position, or more. In such an embodiment, the lock member has more than one feature, such as a recess or protrusion, or the anvil distal end has more than one recess or protrusion.
Operation of actuation assembly 100 is described herein in terms of use with the surgical instrument depicted in FIG. 1A. In operation, tissue is positioned between anvil 30 and cartridge 28 (not explicitly shown). When tissue is properly positioned between the anvil 30 and cartridge 28, a user manually approximates (e.g., in the direction of directional arrow D) the first and second jaw members, 30a and 28a, respectively, toward one another. Curved portion 38 is received into opening 40 where protrusion 42 releasably engages the curved portion 38 (see FIG. 2B, for example). The top portion 104c aligns with the track 112 in first jaw member 130. Subsequently, movable handle 18 is moved through an actuation stroke causing the cable 102 to pull actuation head 104 proximally, which results in knife blade 108 translating proximally within knife channel 32 and bottom portion 104b and top portion 104c of the actuation head 104 translating proximally within respective I-beam tracks 120 and 112. During proximal movement of the actuation head 104, the leading edge 104a, or portion thereof, contacts the plurality of pushers 106b causing the corresponding plurality of staples 106a to eject from the cartridge 28 and form within staple forming pockets 44 associated with the anvil 30 such that at least one staple line is formed in tissue (see FIG. 2C, for example). During proximal movement of the knife blade 108, the proximal edge 108a severs the stapled tissue. Moreover, because cable 102 is flexible and capable of bending and/or articulating, the practical challenges associated with conventional actuation assemblies may be diminished and/or alleviated.
With reference to FIGS. 6-7B, and initially with reference to FIG. 6, a surgical stapling instrument 600 is shown with a loading unit 626 that may be employed with an actuation assembly 100. The operative features of the surgical stapling instrument 600 with loading unit 626 and components associated therewith are similar to surgical stapling instrument 10 with the loading unit 26 described hereinabove. So as not to obscure the present disclosure with redundant information, only the features that are unique to the loading unit 626 and surgical instrument 600 will be described herein.
In the embodiment illustrated in FIGS. 6-7B, a movable handle 618 is configured to approximate a first jaw 630a toward a second jaw 628a. In the embodiment illustrated in FIGS. 6-7B, the first jaw 630a is pivotably coupled to a proximal end of the end effector 624 and biased in a normally open configuration. Additionally, the movable handle 618 is configured to function in a manner as described hereinabove with respect to movable handle 18. That is, movable handle 618 produces a pulling force that drives actuation head 104 associated with the actuation assembly 100 proximally causing a plurality of the staples associated with a cartridge assembly 28 to deploy from the cartridge assembly 28.
With reference to FIGS. 7A and 7B, a camming feature 610 may be employed when the movable handle 618 and is configured to approximate the first jaw 630a toward a second jaw 628a. Camming feature 610 is operably associated with an end effector 624. Camming feature 610 is similar to camming feature 110 described above. More particularly, a pivot pin 614 is operably associated with the end effector 624 adjacent the cartridge 28 and operatively connects to the first jaw 630a. In certain embodiments, the first jaw 630a may include one or more cam slots, e.g., similar to cam slot 116, that is configured to facilitate movement of the first jaw 630a. 
A push rod 682 is in mechanical communication with movable handle 618 via a drive mechanism (not shown). One or more cam pins or protuberances 638 are operably disposed at a distal end of the push rod 682 and are in translatable communication with one or more corresponding cam slots 620 extending partially along a length of the end effector 624 adjacent the first jaw member 630 (see FIG. 6 in combination with FIG. 7A). In the embodiment illustrated in FIGS. 6-7B, a pair of protuberances 638 is operably disposed within a corresponding pair of cam slots 620. Each of the protuberances 638 is configured to cause first jaw member 630a to move toward the second jaw member 628a when the protuberance 638 is pushed distally within the cam slot 620 and contacts a portion of the first jaw member 630a. 
First jaw member 630a is configured similar to first jaw member 30a. In FIGS. 6-7B, a generally flat (or in certain instances may be generally arcuate) camming surface 622 is located at a proximal end of the first jaw member 630a. Camming surface 622 is in mechanical communication with the protuberance 638. In this instance, the jaw 630a functions as a moment arm created by the distance between 638 and 614, see FIG. 7A for example. More particularly, when the protuberance 638 is pushed distally within the cam slot 620, protuberance 638 contacts a portion of the camming surface 622, which, in turn, effects approximation of the first jaw member 630a toward the second jaw member 628a (FIG. 7B).
In operation, tissue is positioned between anvil 30 and cartridge 28. When tissue is properly positioned between the anvil 30 and cartridge 28, movable handle 618 is moved through an approximation stroke to approximate the first and second jaw members, 630a and 628a, respectively, toward one another. More particularly, when movable handle 618 is moved through the approximation stroke, push rod 682 is forced distally (e.g., via a drive mechanism) pushing protuberances 638 distally within the cam slots 620. During distal translation of the protuberances 638 within the cam slots 620, a portion of the protuberances 638 contacts a portion of the camming surface 622, this, in turn, effects approximation of the first jaw member 630a toward the second jaw member 628a. During the approximation stroke, curved portion 38 is received into opening 40 where protrusion 42 releasably engages the curved portion 38 (FIG. 7B). Subsequently, movable handle 18 may be moved through an actuation stroke causing the actuation member and operative components associated therewith to function in a manner described hereinabove.
With reference to FIGS. 8-9B, and initially with reference to FIG. 8, a surgical stapling instrument 800 is shown with a loading unit 826 that may be employed with an actuation assembly 100. The operative features of the surgical stapling instrument 800 with loading unit 826 and components associated therewith are similar to the surgical stapling instrument 600 with loading unit 626 described hereinabove. So as not to obscure the present disclosure with redundant information, only the features that are unique to the loading unit 826 and surgical instrument 800 will be described herein.
In the embodiment illustrated in FIGS. 8-9B, the loading unit 826 and/or a surgical stapling instrument 800 are configured for use with a laparoscopic surgical procedure. That is, an end effector 824 of the loading unit 826 is configured for insertion into an access port “P,” see FIG. 9A, for example. Surgical port “P” may be a commonly-used trocar assembly and will not be described in further detail.
In the embodiment illustrated in FIGS. 8-9B, loading unit 826 includes an articulation element “A.” Loading units that include an articulation element “A” are common in the art. One type of articulation element “A” that may be employed with the loading unit 826 is disclosed in commonly-assigned U.S. Pat. No. 5,865,361 to Milliman et al., the contents of which having been previously incorporated by reference in its entirety.
In FIGS. 8-9B, the loading unit 826 has a push rod 882. More particularly, the push rod 882 is flexible and confined and supported in the elongated shaft so that it (the push rod 882) will not buckle during translation within the elongated shaft. Thus, in the instance where the end effector 824 is in an articulated position (see FIG. 9A, for example), the push rod 882 flexes or bends to the contour of the articulated element “A” and/or the end effector 824. The operative components associated with the push rod 882 are similar to push rod 682 described above. More particularly, push rod 882 is in mechanical communication with a movable handle 818 via a drive mechanism (not shown). A pair of cam pins or protuberances 838 is operably disposed at a distal end of the push rod 882 and is in translatable communication with a corresponding pair of cam slots 820 extending partially along a length of the end effector 824 adjacent the first jaw member 830a (FIG. 9A). Each of the protuberances 838 is configured to cause first jaw member 830a to move toward the second jaw member 828a when the protuberance 838 is pushed distally within the cam slot 820 and contacts a portion of the first jaw member 830a. 
In operation, an incision is made in tissue of a patient. An access port “P” is inserted into the incision. Thereafter, the end effector 824 may be inserted into and through the access port “P” (see FIG. 9A, for example). Tissue is positioned between anvil 30 and cartridge 28. When tissue is properly positioned between the anvil 30 and cartridge 28, movable handle 818 is moved through an approximation stroke to approximate the first and second jaw members, 830a and 828a, respectively, toward one another. Curved portion 38 is received into opening 40 where protrusion 42 releasably engages the curved portion 38 (FIG. 9B). Subsequently, movable handle 18 may be moved through an actuation stroke causing the actuation member and operative components associated therewith to function in a manner described hereinabove.
From the foregoing and with reference to the various figures, those skilled in the art will appreciate that certain modifications can also be made to the present disclosure without departing from the scope of the same. For example, in an embodiment, actuation assembly 400 may be configured for use with a end effector 417 that is configured to pivot about a point 418 at a distal end thereof (see FIG. 10, for example). In the embodiment illustrated in FIG. 8, the actuation assembly 400 may be configured to operate in a manner as previously described herein with reference to actuation assembly 100. For example, end effector 417 may include a cartridge 428 including a track 420, an anvil assembly 430 including a track 412, a track 432, and all components associated with actuation assembly 100 previously described above. In the embodiment illustrated in FIG. 8, cable 102 may extend within anvil 420 and connect to a top portion 410 of knife blade 408.
While several embodiments of the disclosure have been shown in the drawings and/or discussed herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

## Claims

1. A surgical instrument configured to join tissue, comprising:
a handle assembly including an actuator member;
an elongated shaft extending distally from the handle assembly and defining a first longitudinal axis;
an end effector disposed adjacent a distal portion of the elongated portion, the end effector having a pair of first and second jaw members defining a gap therebetween, at least one of the first and second jaw members being pivotably movable from an open position wherein the jaw members are disposed in spaced relation relative to one another, to a clamping position wherein each of the first and second jaw members cooperate to grasp tissue, each of the first and second jaw members being elongate and defining a second longitudinal axis and each of the first and second jaw members including a respective longitudinal track;
an actuation assembly disposed in mechanical cooperation with the end effector, wherein actuation of the actuator member causes at least a portion of the actuation assembly to translate from a distal portion of the end effector towards a proximal portion of the end effector through the tracks in the first and second jaw members;
the first jaw member having a surgical stapling cartridge and a distal end extending transversely to the second longitudinal axis at least partially enclosing the gap between the first jaw member and second jaw member; and
a lock for locking the first jaw member to the second jaw member.

2. A surgical instrument according to claim 1, wherein the second jaw member is an anvil assembly.

3. A surgical instrument according to claim 2, wherein proximal movement of the actuation assembly causes staples to be ejected from the cartridge assembly towards the anvil assembly.

4. A surgical instrument according to claim 1, wherein the actuation assembly includes an actuation head having a knife with a proximal edge configured to sever tissue.

5. A surgical instrument according to claim 1, wherein a top and bottom portion of the actuation head forms an “I” beam configuration, such that the top and bottom portions of the actuation head are receivable within respective tracks associated with the first and second jaw members.

6. A surgical instrument according to claim 1, wherein a cam slot and cam pin configuration is operably associated with the end effector and configured to facilitate remote approximation of the first and second jaw members.

7. A surgical instrument according to claim 1, wherein the distal end of the second jaw member is configured to house at least a portion of the actuation assembly prior to actuation of the actuation member.

8. A surgical instrument according to claim 1, further comprising an actuation cable disposed in mechanical cooperation with the actuation assembly and with the actuation member.

9. A surgical instrument according to claim 1, further comprising an approximation member disposed in mechanical cooperation with the handle assembly, wherein actuation of the approximation member causes distal translation of an approximation assembly which causes the end effector to move towards its second position.

10. A surgical instrument according to claim 1, wherein the end effector is movable between a parallel position where the first longitudinal axis is substantially parallel to the second longitudinal axis and an offset position where the first longitudinal axis and the second longitudinal axis are offset from each other.

11. A surgical instrument according to claim 1, wherein the end effector is part of a disposable loading unit.

12. A surgical instrument according to claim 1, wherein at least one of the jaw members is pivotable with respect to the other about a pivot point disposed on a proximal portion of the end effector.

13. A surgical instrument according to claim 1, wherein at least one of the jaw members is pivotable with respect to the other about a pivot point disposed on a distal portion of the end effector.

14. A surgical instrument according to claim 1, wherein the surgical instrument is configured for a laparoscopic surgical procedure.

15. A surgical instrument according to claim 1, wherein the second jaw member has a lock member for securely engaging the distal end of the first jaw member.

16. A surgical instrument according to claim 15, wherein the lock member for securely engaging the distal end of the first jaw member is biased in a generally proximal direction.

17. A surgical instrument according to claim 15, wherein the lock member has a first position that secures the first jaw member and a second position for allowing the first jaw member to move.

18. A surgical instrument according to claim 15, further comprising a pusher extending from the lock member to the handle assembly.

19. A surgical instrument according to claim 18, wherein the pusher is accessible by a user of the instrument to move the pusher, thereby releasing the first jaw member.

20. A surgical instrument according to claim 15, wherein the first jaw member has more than one closed position and the lock member has more than one feature for securing the position of the first jaw member.