Patent Publication Number: US-2023135070-A1

Title: Cartridge assemblies for surgical staplers

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application claiming priority under  35  U.S.C. § 120 to U.S. patent application Ser. No. 16/727,160, entitled CARTRIDGE ASSEMBLIES FOR SURGICAL STAPLERS, filed Dec. 26, 2019, now U.S. Patent Application Publication No. 2020/0222047, which is a divisional application claiming priority under 35 U.S.C. § 121 to U.S. patent application Ser. No. 14/527,384, entitled CARTRIDGE ASSEMBLIES FOR SURGICAL STAPLERS, filed Oct. 29, 2014, which issued on Dec. 31, 2019 as U.S. Pat. No. 10,517,594, the entire disclosures of which is hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     The present invention relates to stapling instruments and, in various embodiments, to a surgical stapling instrument for producing one or more rows of staples. 
     A stapling instrument can include a pair of cooperating elongate jaw members, wherein each jaw member can be adapted to be inserted into a patient and positioned relative to tissue that is to be stapled and/or incised. In various embodiments, one of the jaw members can support a staple cartridge with at least two laterally spaced rows of staples contained therein, and the other jaw member can support an anvil with staple-forming pockets aligned with the rows of staples in the staple cartridge. Generally, the stapling instrument can further include a pusher bar and a knife blade which are slidable relative to the jaw members to sequentially eject the staples from the staple cartridge via camming surfaces on the pusher bar and/or camming surfaces on a wedge sled that is pushed by the pusher bar. In at least one embodiment, the camming surfaces can be configured to activate a plurality of staple drivers carried by the cartridge and associated with the staples in order to push the staples against the anvil and form laterally spaced rows of deformed staples in the tissue gripped between the jaw members. In at least one embodiment, the knife blade can trail the camming surfaces and cut the tissue along a line between the staple rows. Examples of such stapling instruments are disclosed in U.S. Pat. No. 7,794,475, entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FOR SECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FOR DEPLOYING THE SAME, the entire disclosure of which is hereby incorporated by reference herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various features of the embodiments described herein are set forth with particularity in the appended claims. The various embodiments, however, both as to organization and methods of operation, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows: 
         FIG.  1    is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  1 A  is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  1 B  is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  1 C  is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  1 D  is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  1 E  is a perspective view of a staple drive assembly showing an actuation sled and a staple pusher system in accordance with at least one embodiment; 
         FIG.  2    is a perspective view of a surgical stapling apparatus in accordance with at least one embodiment; 
         FIG.  2 A  is a side elevational view of an alternative end effector of the surgical stapling apparatus of  FIG.  2    in accordance with at least one embodiment; 
         FIG.  2 B  is a side elevational view of the end effector  FIG.  2 A  in a partially open configuration; 
         FIG.  2 C  is a perspective view of an end effector of the surgical stapling apparatus of  FIG.  2    in accordance with at least one embodiment; 
         FIG.  2 D  is a cross sectional view of the end effector of  FIG.  2 C  in a closed configuration in accordance with at least one embodiment; 
         FIG.  3    is an exploded perspective view of a staple cartridge, staples, staple pushers, and an actuation sled in accordance with at least one embodiment; 
         FIG.  3 A  is an exploded perspective view of a staple cartridge, staples, and staple pushers in accordance with at least one embodiment; 
         FIG.  3 B  is a side perspective view of staples and a staple pusher in accordance with at least one embodiment; 
         FIG.  3 C  is a side elevational view of a “V” shaped staple in accordance with at least one embodiment; 
         FIG.  3 D  is a side elevational view of a “U” shaped staple in accordance with at least one embodiment; 
         FIG.  3 E  is a perspective view of a “U” shaped staple positioned onto a staple pusher plate in accordance with at least one embodiment; 
         FIG.  3 F  is a perspective view of a “U” shaped staple positioned onto a staple pusher plate in accordance with at least one embodiment; 
         FIG.  3 G  is a partial cross-sectional view of a “U” shaped staple and the staple pusher plate before the “U” shaped staple is positioned onto the staple pusher plate; 
         FIG.  3 H  is a partial cross-sectional view of the “U” shaped staple and the staple pusher plate of  FIG.  3 G  while the “U” shaped staple is positioned onto the staple pusher plate; 
         FIG.  3 I  is a partial perspective view of a staple deposited in a retention slot in accordance with at least one embodiment; 
         FIG.  3 J  is a partial cross-sectional view of along the line  3 J- 3 J of  FIG.  3 I ; 
         FIG.  4    is a top plan view of the staple cartridge of  FIG.  3    with the actuation sled in an initial position; 
         FIG.  5    is a side cross-sectional view of a proximal portion of the staple cartridge taken along section line  5 - 5  of  FIG.  4   ; 
         FIG.  6    is a front perspective view of the staple pusher of  FIG.  1   ; 
         FIG.  7    is a rear perspective view of the staple pusher of  FIG.  1   ; 
         FIG.  8    is a top plan view of the staple pusher of  FIG.  1   ; 
         FIG.  9    is a side cross-sectional view taken along section line  9 - 9  of  FIG.  8   ; 
         FIG.  10    is a side cross-sectional view taken along section line  10 - 10  of  FIG.  8   ; 
         FIG.  11    is a front perspective view of the actuation sled of  FIG.  1   ; 
         FIG.  12    is a rear perspective view of the actuation sled of  FIG.  1   ; 
         FIG.  13    is a top plan view of the actuation sled of  FIG.  1   ; 
         FIG.  14    is a side cross-sectional view taken along section line  14 - 14  of  FIG.  13   ; 
         FIG.  15    is a side cross-sectional view taken along section line  15 - 15  of  FIG.  13   ; 
         FIG.  16    is a side cross-sectional view of the staple drive assembly of  FIG.  1    showing the initial engagement between the cam members of the staple pusher of  FIG.  6    and the cam wedges of the actuation sled as the actuation sled moves in the direction of arrow A; 
         FIG.  17    is a side cross-sectional view of the staple drive assembly of  FIG.  1    showing the continued engagement between the cam members of the staple pusher of  FIG.  6    and the cam wedges of the actuation sled as the actuation sled continues to move in the direction of arrow A; and 
         FIG.  18    is a top plan view taken along section line  18 - 18  in  FIG.  17    of the staple drive assembly of  FIG.  17   . 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate various embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION 
     Applicant of the present application owns the following patent application which was filed on Oct. 29, 2014 and which is herein incorporated by reference in its entirety: 
     U.S. patent application Ser. No. 14/527,398, entitled STAPLE CARTRIDGES COMPRISING DRIVER ARRANGEMENTS, now U.S. Patent Application Publication No. 2016/0120545. 
     Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. It will be understood by those skilled in the art, however, that the embodiments may be practiced without such specific details. In other instances, well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. Those of ordinary skill in the art will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and illustrative. Variations and changes thereto may be made without departing from the scope of the claims. 
     The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a surgical system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements. Likewise, an element of a system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. 
     The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” referring to the portion closest to the clinician and the term “distal” referring to the portion located away from the clinician. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical”, “horizontal”, “up”, and “down” may be used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and/or absolute. 
     Various exemplary devices and methods are provided for performing laparoscopic and minimally invasive surgical procedures. However, the person of ordinary skill in the art will readily appreciate that the various methods and devices disclosed herein can be used in numerous surgical procedures and applications including, for example, in connection with open surgical procedures. As the present Detailed Description proceeds, those of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, etc. The working portions or end effector portions of the instruments can be inserted directly into a patient&#39;s body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced. 
     The present disclosure is directed toward a staple drive assembly for use in a staple cartridge. The staple drive assembly may also be used in a disposable loading unit and/or any other suitable device and can be configured to deploy numerous types of staples and/or fasteners. The staple drive assembly includes an actuation sled and at least one staple driver. The staple cartridge includes a tissue contacting and/or supporting surface having a number of staple cavities wherein each staple cavity is adapted for releasably receiving a staple. The staple cartridge may include a guide channel / knife slot extending from a proximal portion to a distal portion along its longitudinal axis. In one embodiment, the staple cartridge is adapted for use in a surgical stapler having a drive mechanism. 
     An example of a surgical stapler having a staple drive assembly is disclosed in U.S. Pat. No. 6,669,073, entitled SURGICAL STAPLING APPARATUS, which issued on Dec. 30, 2003, the entire disclosure of which is incorporated herein by reference. The disclosures of U.S. Pat. No. 7,866,528, entitled STAPLE DRIVE ASSEMBLY, filed Jan. 11, 2011 and U.S. Patent Application Publication No. 2013/0327810, entitled FASTENER CARTRIDGE ASSEMBLY COMPRISING A FIXED ANVIL AND A STAPLE DRIVER ARRANGEMENT, filed Aug. 15, 2013, now U.S. Pat. No. 9,839,427, are also hereby incorporated by reference herein in their entireties. 
     A staple drive assembly  100 , in accordance with one embodiment of the present disclosure, is illustrated in  FIG.  1   . The staple drive assembly  100  includes an actuation sled  110  and at least one staple pusher arrangement or system  160 . The actuation sled  110  includes a base  112 , a first camming member  120 , a second camming member  140 , and a guide member  150 . The first and second camming members  120  and  140  include respective first or leading cam wedges  122  and  142  and respective second or trailing cam wedges  124  and  144 . In one embodiment, staple drive assembly  100  is adapted for use in a surgical stapler having at least two linear rows of staples such as an endoscopic or laparoscopic stapler. 
     Referring to  FIG.  2   , a surgical stapler  10  is shown. The surgical stapler  10  includes a trigger assembly  30 , a body portion  12 , a staple cartridge  40 , and an anvil assembly  70 . Trigger assembly  30  includes a pivotal trigger  32 . Pivotal movement of the trigger  32  during an actuation sequence of the trigger  32  translates pivotal movement of the trigger  32  into linear movement of a drive mechanism (not shown). The drive mechanism is operatively coupled to an actuation sled in the staple cartridge  40  to translate linear movement of the drive mechanism to linear movement of the actuation sled. The surgical stapler  10  is movable such that a portion of body tissue (not shown) may be positioned between the anvil assembly  70  and the staple cartridge  40 . Actuation of stapler  10  moves anvil assembly  70  towards staple cartridge  40  thereby grasping or retaining the portion of body tissue therebetween. In addition, once the portion of body tissue is grasped between the anvil assembly  70  and the staple cartridge  40 , continued actuation of stapler  10  discharges staples  50  ( FIG.  3   ) through the portion of body tissue and against the anvil assembly  70  to form completed staples  50 . 
     A staple drive assembly such as, for example, the staple drive assembly  100  ( FIG.  1   ), the staple drive assembly  200  ( FIG.  1 A ), the staple drive assembly  300  ( FIG.  1 B ), the staple drive assembly  400  ( FIG.  1 C ), the staple drive assembly  700  (FIG.  1 D), the staple drive assembly  800  ( FIG.  1 E ) may be incorporated into the staple cartridge  40  of surgical stapler  10 . Alternately, the staple drive assembly  100 ,  200 ,  300 ,  400 ,  700 , and/or  800  may be incorporated into other known stapling devices including open-type surgical stapling devices and other endoscopic or laparoscopic surgical stapling devices, for example. While the present disclosure describes embodiments involving an actuation sled, it also will be appreciated that the design characteristics and function of the sled camming members may be incorporated directly into cam bars or firing wedges, which in turn are connected to the firing mechanism of the surgical stapling instrument. 
       FIG.  3    illustrates a staple cartridge  40 ′ including the staple drive assembly  100 . The staple cartridge  40 ′ includes a plurality of fasteners or staples  50  and a corresponding number of staple pockets or retention slots  60 . A tissue contacting and/or supporting surface  44  is defined by a top surface of the staple cartridge  40 ′. A guide channel  42  extends substantially the length of staple cartridge  40 ′ and is adapted for slidably receiving guide member  150  of actuation sled  110  as shown in  FIG.  4   . In  FIG.  4   , sled  110  is shown positioned at the proximal end of the staple cartridge  40 ′ with the guide member  150  disposed in the guide channel  42 . The guide channel  42  cooperates with the guide member  150  for aligning and positioning the actuation sled  110  in the staple cartridge  40 ′ as it translates longitudinally from a proximal end to a distal end of the staple cartridge  40 ′. Guide channel  42  may also facilitate passage of a knife blade (not shown) through the staple cartridge  40 ′. In various instances, a knife blade can be mounted to the guide member  150 . 
     In  FIG.  5   , which is a cross-sectional view taken along line  5 - 5  of  FIG.  4   , the actuation sled  110  is shown disposed in the proximal end of staple cartridge  40 ′ in a first or ready position, for example. In the ready position, the actuation sled  110  is capable of translating distally through the staple cartridge  40 ′, in the direction indicated by arrow A, and sequentially engaging the staple pushers  160  ( FIG.  3   ). The actuation sled  110  is translatable along a longitudinal axis of the staple cartridge  40 ′ from its ready position to a second or end position located in a distal portion of the staple cartridge  40 ′. 
     As previously discussed, the staple pusher  160  includes prongs or pusher plates  166  that are laterally and longitudinally spaced apart as well as first and second cam members  162 ,  164  interposed between adjacent pusher plates  166 . More specifically, as discussed hereinabove, in one embodiment of the present disclosure, each staple pusher  160  includes a plurality of independent pusher plates  166  that are substantially parallel to a longitudinal axis of staple cartridge  40 ′ and parallel to a centerline CL of each staple pusher  160  ( FIG.  8   ). Additionally, first and second cam members or portions 162 ,  164  are also substantially parallel to centerline CL ( FIG.  8   ). 
     Staple pusher  160 , as viewed from left to right in  FIG.  8    (i.e. distal to proximal), includes an inboard pusher plate  166  that is most distal along centerline CL. A middle pusher plate  166  is laterally spaced apart from inboard pusher plate  166  and is axially offset in the proximal direction from inboard pusher plate  166 . An outboard pusher plate  166  is laterally spaced apart from middle pusher plate  166  and is axially offset in the proximal direction from middle pusher plate  166 . Further still, first cam member  162  is disposed between inboard pusher plate  166  and middle pusher plate  166  while second cam member  164  is disposed between middle pusher plate  166  and outboard pusher plate  166 . Configured thusly, staple pusher  160  has an arrangement where pusher plates  166  are longitudinally staggered from a distal portion of staple pusher  160  to a proximal portion of staple pusher  160  as seen in  FIG.  8   . An outboard pusher plate  166  is closer to a distal portion of a staple cartridge that incorporates the staple pusher  160  than a middle pusher plate  166  and the middle pusher plate  166  is closer to the distal portion of the staple cartridge than the inboard pusher plate  166 , for example. 
     First and second cam members  162 ,  164  include respective first and second cam surfaces  162   a ,  162   b , and  164   a ,  164   b  ( FIGS.  9  and  10   ). At the intersection of first and second cam surfaces  162   a ,  162   b  and  164   a ,  164   b  are respective transition points  162   c ,  164   c . A plane T ( FIG.  10   ) extending through transition points  162   c ,  164   c  is parallel to respective tops  163 ,  165  of cam members  162 ,  164 . In one embodiment, first cam surfaces  162   a ,  164   a  define a first engagement or receiving angle with respect to tops  163 ,  165  of respective first and second cam members  162 ,  164 . Second cam surfaces  162   b ,  164   b  define a second engagement or receiving angle with respect to plane T. First and second receiving angles are complementary to respective first and second drive angles of camming members  120 ,  140  of actuation sled  110 . 
     With reference to  FIGS.  11 - 15   , several views of one embodiment of actuation sled  110  are shown. First and second camming members  120 ,  140  each include a first or leading cam wedge  122 ,  142 , respectively, that is laterally and longitudinally spaced apart from a second or trailing cam wedge  124 ,  144 , respectively. The lateral and longitudinal offset distances of each pair of camming wedges substantially corresponds to the lateral and longitudinal offset distances between corresponding cam members  162 ,  164 . First cam wedges  122 ,  142  are laterally and longitudinally spaced from second cam wedges  124 ,  144 , respectively, by a substantially identical amount such that first and second camming members  120 ,  140  are symmetrical about a central longitudinal axis of actuation sled  110 . Leading cam wedges  122 ,  142  include respective first and second drive faces  122   a ,  122   b ,  142   a , and  142   b . First drive faces  122   a ,  142   a  form first drive angles on camming members  120 ,  140  with respect to base  112  of actuation sled  110 . At the intersection of first and second drive faces  122   a ,  142   a  and  122   b ,  142   b  are respective transition points  123 ,  143 . A plane X extending through transition points  123 ,  143  is substantially parallel to base  112 . Second drive faces  122   b ,  142   b  form respective second drive angles on camming members  120 ,  140  with respect to plane X. Plane X is also substantially parallel to tissue contacting surface  44  of staple cartridge  40 ′. 
     Similarly, trailing cam wedges  124 ,  144  include respective first and second drive faces  124   a ,  124   b ,  144   a , and  144   b . First drive faces  124   a ,  144   a  form first drive angles on camming members  120 ,  140  with respect to base  112  ( FIG.  5   ) of actuation sled  110 . At the intersection of first and second drive faces  124   a ,  124   b  and  144   a ,  144   b  are respective transition points  125 ,  145 . Plane X extends through transition points  125 ,  145  and is substantially parallel to base  112 . Second drive faces  124   b ,  144   b  form respective second drive angles on camming members  120 ,  140  with respect to plane X. 
     Interaction between the actuation sled  110  and the staple pusher  160  of the staple drive assembly  100  is shown in  FIGS.  16 - 18    and discussed in detail hereinafter. The interactions between actuation sleds of other staple drive assemblies described hereinafter and their corresponding staple pushers can be the same or, or at least similar, in many respects to the interaction between the actuation sled  110  and the staple pusher  160 . Accordingly, for the sake of brevity, the detailed description of such interactions is omitted. 
     Initially, as illustrated in  FIG.  16   , actuation sled  110  translates distally through staple cartridge  40 ′ in the direction indicated by arrow A (see also  FIG.  5   ) causing first drive face  122   a  to slidably engage first cam surface  162   a  and urge staple pusher  160  from its first or rest position in a generally vertical direction as indicated by arrow B. Because the lateral and longitudinal offset distances of wedges  122 ,  124  correspond to the lateral and longitudinal offset distances between cam wedges  162 ,  164 , first drive face  124   a  substantially simultaneously slidably engages first cam surface  164   a  thereby urging staple pusher  160  in a generally vertical direction as indicated by arrow B. Since cam surfaces  162   a  and  164   a  are longitudinally offset, staple pusher  160  is driven in a controlled and balanced manner and any tendency of staple pusher  160  to tilt or rotate counterclockwise (as viewed in  FIGS.  16 - 17   ) is minimized as staple pusher  160  is driven through retainer slot  60 . First drive faces  122   a ,  124   a  and respective first cam surfaces  162   a ,  164   a  have complementary angles that maximize translation of longitudinal motion of actuation sled  110  to vertical motion of staple pusher  160 . 
     Referring now to  FIG.  17   , continued distal movement of actuation sled  110  further urges staple pusher  160  generally vertically to an intermediate position, such that second drive faces  122   b ,  124   b  slidably engage respective second cam surfaces  162   b ,  164   b  while first drive faces  122   a ,  124   a  substantially simultaneously disengage from respective first cam surfaces  162   a ,  164   a . Similarly, second drive faces  122   b ,  124   b  and respective second cam surfaces  162   b ,  164   b  have complementary angles to maximize translation of longitudinal motion of actuation sled  110  to vertical motion of staple pusher  160 . The corresponding lateral and longitudinal offset of second drive faces  122   b ,  124   b  and respective second cam surfaces  162   b ,  164   b  continue to control the advancement of staple pusher  160  so as to minimize any tendency of staple pusher  160  to tilt or rotate in a counterclockwise direction as viewed in  FIGS.  16  and  17   . Continuing distal movement of actuation sled  110  continues to urge staple pusher  160  vertically to its second or end position immediately prior to the disengagement between second drive faces  122   b ,  124   b  and respective second cam surfaces  162   b ,  164   b.    
     Further to the above, longitudinal motion of actuation sled  110  in the direction indicated by arrow A results in first and second camming members  120 ,  140  slidably engaging staple pushers  160  as shown in  FIGS.  16 - 18   . Sliding engagement between leading cam wedges  122 ,  142  and first cam members  162  in cooperation with the substantially simultaneous engagement between trailing cam wedges  124 ,  144  and second cam members  164  improve the longitudinal stability of the staple pushers  160  during vertical motion as follows. Leading cam wedges  122 ,  142  are longitudinally spaced apart from trailing cam wedges  124 ,  144  by a predetermined amount. Since respective first and second cam members  162 ,  164  are longitudinally spaced apart by a comparable, but complementary amount, longitudinal movement of actuation sled  110  results in the substantially simultaneous, but offset engagement of leading cam wedges  122 ,  124  and trailing cam wedges  124 ,  144  with respective first and second cam members  162 ,  164  thereby transferring the longitudinal movement of actuation sled  110  to vertical movement of staple pusher  160  at longitudinally spaced apart impact points. 
     Referring to  FIG.  3 A , a staple cartridge  2140  includes a tissue contacting and/or supporting portion  2161 . The tissue contacting portion  2161  includes three tissue contacting and/or supporting surfaces  2161   a - 2161   c . Tissue contacting surfaces  2161   a - 2161   c  are planar, or at least substantially planar, structures that are substantially parallel to one another, but are not co-planar with one another. Said another way, the tissue contacting portion  2161  is stepped. A set of tissue contacting surfaces  2161   a - 2161   c  is disposed on each side of a knife channel  2148 . The tissue contacting surfaces  2161   c  have a knife channel  2148  defined therebetween. The tissue contacting surfaces  2161   c  are co-planar with one another. The tissue contacting surfaces  2161   a - 2161   c  include different heights as measured from a datum such as the place including the top of the knife channel  2148 , for example. Additionally, the tissue contacting surfaces  2161   a  on opposite sides of the knife channel  2148  are co-planar with one another. Similarly, the tissue contacting surfaces  2161   b  on opposite sides of the knife channel  2148  are co-planar with one another. Furthermore, the tissue contacting surfaces  2161   c  on opposite sides of the knife channel  2148  are co-planar with one another. Although the drawings show planar tissue contacting surfaces  2161   a - 2161   c , the present disclosure envisions curved or angled tissue contacting surfaces as well as other kinds of tissue contacting surfaces having other shapes and structures. 
     A wall or any other suitable structure interconnects the tissue contacting surfaces  2161   a  and  2161   b . Similarly, a suitable structure such as a wall interconnects the tissue contacting surfaces  2161   b  and  2161   c . The walls or interconnecting structures may be oriented orthogonally with respect to the tissue contacting surfaces  2161   a - 2161   c . The present disclosure, however, contemplates walls or interconnecting structures oriented in different directions such as angled, curved or other configurations. 
     In certain instances, referring to  FIG.  3 A , the tissue contacting surface  2161   c  has a height greater than the tissue contacting surface  2161   b ; and the tissue contacting surface  2161   b  has a height greater than the tissue contacting surface  2161   a . While tissue contacting surfaces  2161   a - 2161   c  are shown as decreasing in height between the first tissue contacting surface  2161   a  and the third tissue contacting surface  2161   c , it is envisioned that the heights of each tissue contacting surface may vary depending on the particular surgical procedure. Other features of tissue contacting surfaces  2161   a - 2161   c  may also vary according to the circumstances. 
     Each tissue contacting surface  2161   a - 2161   c  includes a plurality of retention slots  2144  formed therein. Retention slots  2144  are disposed in a plurality of rows  2144   a ,  2144   b , and  2144   c  that are located in tissue contacting surfaces  2161   a ,  2161   b , and  2161   c , respectively. The linear rows of retention slots  2144   a - 2144   c  are staggered along the longitudinal axis of staple cartridge  2140  as shown in  FIG.  3 A . Particularly, the distal most retention slots  2144  of rows  2144   a ,  2144   c  are closer to a distal end of the staple cartridge  2140  than the distal most retention slots  2144  of row  2144   b . On the other hand, the most proximal retention slots  2144  of rows  2144   b  are closer to the proximal end of cartridge  2140  than the most proximal retention slots  2144  of rows  2144   a  and  2144   c . Linear rows of retention slots  2144   a - 2144   c  having other suitable arrangements are within the scope of the present disclosure as long as they are capable of receiving surgical fasteners. 
     In certain instances, as illustrated in  FIG.  3 A , the retention slots of the row of retention slots  2144   a  are positioned at regular intervals along a first longitudinal axis. Spaces between adjacent retention slots of the row of retention slots  2144   a  can be referred to as staple gaps in the first longitudinal axis as tissue positioned over such spaces will not be stapled by staples ejected from the retention slots of the row of retention slots  2144   a . The retention slots of the row of retention slots  2144   b  are also positioned at regular intervals along a second longitudinal axis. The retention slots of the row of retention slots  2144   b  are staggered with respect to the retention slots of the row of retention slots  2144   a . The retention slots of the row of retention slots  2144   b  are positioned laterally with respect to the staple gaps in the row of retention slots  2144   a . Spaces between adjacent retention slots of the row of retention slots  2144   b  can also be referred to as staple gaps in the second longitudinal axis as tissue positioned over such spaces will not be stapled by staples ejected from the retention slots of the row of retention slots  2144   b . The retention slots of the row of retention slots  2144   c  are also positioned at regular intervals along a third longitudinal axis. The retention slots of the row of retention slots  2144   c  are staggered with respect to the retention slots of the row of retention slots  2144   b . The retention slots of the row of retention slots  2144   c  are positioned laterally with respect to the staple gaps in the retention slots of the row of retention slots  2144   b.    
       FIG.  3 B  illustrates an arrangement of the surgical fasteners  50   a - 50   c  in the staple cartridge  2140 . Staple cartridge  2140  includes surgical fasteners or staples  50   a ,  50   b , and  50   c . Each staple  50   a ,  50   b , and  50   c  includes a base  52   a - 52   c . Legs  55   a  of the surgical fasteners  50   a  have a first leg length “A”, legs  55   b  of the surgical fasteners  50   b  have a second leg length “B”, and legs  55   c  of surgical fasteners  50   c  have a third leg length “C.” In one embodiment, the first length “A” is greater than the second length “B.” In turn, the second length “B” is greater than the third length “C.” Surgical fasteners  50   a - 50   c  are configured to operate in conjunction with staple pusher  2160 . 
     Surgical fasteners  50   a - 50   c  cooperate with staple pusher  2160  and sled  110  such that the longitudinal translation of sled  110  through staple cartridge  2140  urges pushers  2160  in a vertical direction to eject the surgical fasteners  50   a - 50   c . As shown in  FIG.  3 B , the staple pusher  2160  includes pusher plates  2166   a - 2166   c , each of which has a different vertical dimension. Pusher plate  2166   c  has the greatest vertical dimension and cooperates with the surgical fastener  50   c , which has the smallest leg length. Pusher plate  2166   a  has the smallest vertical dimension and cooperates with the surgical fastener  50   a , which has the largest leg length. Pusher plate  2166   b  has a vertical dimension greater than pusher plate  2166   a , but less than pusher plate  2166   c  and cooperates with surgical fastener  50   b , which has an intermediate leg length, between those of the surgical fasteners  50   a  and  50   c . The surgical fasteners  50   c  are arranged adjacent the knife channel  2148 . Surgical fasteners  50   a  are adjacent to an outer edge of the staple cartridge  2140 , and surgical fasteners  50   b  are disposed therebetween. By providing the surgical fasteners  50   a - 50   c  and pusher plates  2160  with complementary heights, the various sized-staples are formed against the anvil of the stapler into the desired shape. It is also envisioned that other arrangements of pusher plates and surgical fasteners may be used. 
     In various instances, the staple cartridge  2140  may include a single planar tissue contacting surface and the anvil member may be provided with more than one tissue contacting surface so as to define more than one gap with respect to the tissue contacting surface of the staple cartridge. One or both of the staple cartridge and anvil member may have stepped surfaces, angled or sloped surfaces, or curved surfaces that are selected to correspond to staples having predetermined leg lengths. In certain embodiments, more than one tissue contacting surface is provided, on the staple cartridge, the anvil member, or both, with sloped surfaces extending therebetween. In certain embodiments, the staple pushers have heights corresponding to the different staple sizes. The anvil pockets of the anvil assembly, the staple pushers, and/or the actuation sled are arranged to form each of the different sized staples in the desired closed shapes. 
     In certain instances, staple cartridge  2140  includes at least one double staple pusher  2170 , at least one triple staple pusher  2160  and at least one quadruple staple pusher  2180 . As seen in  FIG.  3 A , double staple pusher  2170  has only two pusher plates  2176 , triple staple pusher  2160  has three pusher plates  2166 , and quadruple staple pusher  2180  has four pusher plates  2186 . The staples and pushers are arranged in a pattern on a first side  2148   a  of knife channel  2148  and on a second side  2148   b  of knife channel  2148 , so as to form three longitudinal rows of staples on each side of knife channel  2148 . 
     In certain instances, the rows of staples  50   a  are positioned at regular intervals along a first longitudinal axis. Spaces between adjacent rows of staples  50   a  can be referred to as staple gaps in the first longitudinal axis as tissue positioned over such spaces will not be stapled by staples  50   a . The rows of staples  50   b  are also positioned at regular intervals along a second longitudinal axis. The staples  50   b  are staggered with respect to the staples  50   a . The staples  50   b  are positioned laterally with respect to the staple gaps in the row of staples  50   a . Spaces between adjacent staples  50   b  can also be referred to as staple gaps in the second longitudinal axis as tissue positioned over such spaces will not be stapled by the staples  50   b . The staples  50   c  are also positioned at regular intervals along a third longitudinal axis. The staples  50   c  are staggered with respect to the staples  50   b . The staples  50   c  are positioned laterally with respect to the staple gaps in the row of staples  50   b.    
     Double staple pushers  2170  are disposed at the proximal end of staple cartridge  2140  and are adapted to deploy the most proximal staples  50   b  and  50   c  through retention slots  2144  of rows  2144   b  and  2144   c , respectively. One double staple pusher  2170  interacts with two most proximal staples  50   b  and  50   c  disposed in retention slots  2144  of rows  2144   b  and  2144   c . Quadruple staple pushers  2180  are positioned in the distal end of staple cartridge  2140  and are configured to deploy four of the distal most staples  50   a  and  50   c , including the staples which are deployed through the distal most retention slots  2144  of rows  2144   c ,  2144   a . The quadruple staple pushers  2180  interact with another staple  50   a  in the outermost retention slots  2144  of rows  2144   a , as well as a staple  50   b  in retention slots  2144  of rows  2144   b . For each side  2148   a ,  2148   b  of the staple cartridge, one double staple pusher  2170  is disposed at a proximal end of the staple cartridge  2140  and one quadruple staple pusher  2180  at the distal end of the staple cartridge  2140 . The pushers are arranged in a mirror-image of each other, in either side of the staple cartridge. 
     A plurality of triple staple pushers  2160  extend between double staple pushers  2170  and quadruple staple pushers  2180  in a longitudinal manner and are configured to deploy the staples  50   a ,  50   b  and  50   c  from retention slots  2144  of the innermost rows  2144   c , middle rows  2144   b , and outermost rows  2144   a . One triple staple pusher  2160  interacts with one staple  50   a  disposed in retention slot  2144  of the outermost row  2144   a , one staple  50   b  disposed in retention slot  2144  of rows  2144   b , and one staple  50   c  disposed in retention slot  2144  of the innermost row  2144   c . The pusher plates of the triple staple pushers  2160  have heights that correspond to the size of the staples, as discussed above. 
     Referring now to  FIGS.  2 A and  2 B , an end effector  500  is depicted. The end effector  500  can be employed with the surgical instrument  10 . For example, as illustrated in  FIG.  2 A , the end effector  500  may be coupled to and extend from the body portion  12 . The end effector  500  may comprise a staple cartridge such as, for example, the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), and/or the stable cartridge  2140  ( FIG.  3 A ). In addition, the end effector  500  may include an anvil assembly such as, for example, the anvil assembly  70  ( FIG.  2   ) and/or the anvil assembly  604  ( FIG.  3 C ). 
       FIG.  2 A  depicts an end effector  500  comprising the stable cartridge  2140  and the anvil assembly  70 , for example. In certain instances, the anvil assembly  70  can be movable toward the staple cartridge  2140  ( FIG.  3 A ) to capture tissue therebetween in response to actuation of the trigger  32 , for example. As illustrated in  FIG.  2 A , the end effector  500  includes a cartridge channel  506  which can extend distally from the body portion  12 . The cartridge channel  506  can be configured to receive a staple cartridge such as the staple cartridge  2140 , for example. In certain instances, the cartridge channel  506  is fixedly attached to the body portion  12 . A proximal portion  508  of the cartridge channel  506  may extend, or substantially extend, along a longitudinal axis AA defined by the body portion  12 , as illustrated in  FIG.  2 A . In certain instances, a distal portion  510  of the cartridge channel  506  may deviate from the longitudinal axis AA. The distal portion  510  may extend in a direction that intersects the longitudinal axis AA at an angle a, as illustrated in  FIG.  2 A , for example. 
     In certain instances, the angle a can be any angle selected from a range of about 5 degrees, for example, to about 90 degrees, for example. In certain instances, the angle a can be any angle selected from a range of about 20 degrees, for example, to about 80 degrees, for example. In certain instances, the angle a can be any angle selected from a range of about 30 degrees, for example, to about 50 degrees, for example. In at least one instance, the angle a can be about 45 degrees, for example. 
     Referring again to  FIGS.  2 A and  2 B , the distal portion  510  of the cartridge channel  506  may include a hooking region  514  which can be comprise of a depression in the distal portion  510 , for example. As illustrated in  FIG.  2 B , the hooking region  514  can be configured to capture anatomical structures such as, for example, a blood vessel. In certain instances, the distal portion  510  may comprise a pointed tip  512  which can facilitate positioning of a staple carriage such as the staple cartridge  2140  underneath tissue to be captured between the staple cartridge  2140  and the anvil assembly  70 . The pointed tip  512  can be employed to atraumatically dissect connective tissue, for example, in order to provide a path for positioning the staple cartridge  2140  with respect to an anatomical structure. The anvil assembly  70  can then be moved to capture the anatomical structure between the staple cartridge  2140  and the anvil assembly  70 . In certain instances, the depression is proximal to the pointed tip  512 . 
     In certain instances, as illustrated in  FIGS.  2 A and  2 B , the distal portion  510  may comprise a ramp portion  515 . The ramp portion  515  may be configured to facilitate a transition of tissue caught in the depression of the distal portion  510  to a staple cartridge such as, for example, the staple cartridge  2140 . As described herein, the staple cartridge  2140  may comprise stepped tissue contacting and/or supporting surfaces  2161   a ,  2161   b , and  2161   c . In such instances, the ramp portion  515  can be configured to facilitate the transition of tissue from the depression of the distal portion  510  to the stepped tissue contacting surfaces  2161   a ,  2161   b , and  2161   c . In at least one example, the ramp portion  515  may be split into three sub-ramps that each lead to one of the tissue contacting surfaces  2161   a ,  2161   b , and  2161   c , for example. 
       FIG.  3 C  illustrates a “V” shaped fastener  520 . In certain instances, one or more of the fasteners  50   a ,  50   b , and/or  50   c  may comprise “V” shapes which can be similar to the “V” shape” of the fastener  520  depicted in  FIG.  3 C . In certain instances, the staple cartridge  2140  may comprise a plurality of “V” shaped fasteners  50   a ,  50   b , and  50   c . The “V” shaped fasteners  50   a ,  50   b , and  50   c  can be housed, or at least partially housed, within the retention slots  2144  of the staple cartridge  2140  for deployment into tissue captured between the staple cartridge  2140  and an anvil assembly such as, for example, the anvil assembly  70  ( FIG.  2   ) and/or the anvil assembly  604  ( FIG.  3 C ). 
     Referring to  FIG.  3 C , a “V” shaped staple  520  may be comprised of a base  522 , a first leg  524 , and a second leg  526 . In certain instances, as illustrated in  FIG.  3 C , the legs  524  and  526  may extend from the base  522  in a plane intersecting the base  522 . In certain instances, the first leg  524  and/or the second  526  can form an angle  13  with the base  522 . In certain instances, the angle  13  can be greater than  90  degrees, for example. 
       FIG.  3 D  illustrates a “U” shaped fastener  528 . In certain instances, one or more of the fasteners  50   a ,  50   b , and/or  50   c  may comprise “U” shapes which can be similar to the “U” shape” of the fastener  528  depicted in  FIG.  3 D . In certain instances, the staple cartridge  2140  may comprise a plurality of “U” shaped fasteners  50   a ,  50   b , and  50   c . The “U” shaped fasteners  50   a ,  50   b , and  50   c  can be housed, or at least partially housed, within the retention slots  2144  of the staple cartridge  2140  for deployment into tissue captured between the staple cartridge  2140  and an anvil assembly such as, for example, the anvil assembly  70  ( FIG.  2   ) and/or the anvil assembly  604  ( FIG.  3 C ). 
     Referring to  FIG.  3 D , a “U” shaped staple  528  may be comprised of a base  530 , a first leg  532 , and a second leg  534 . In certain instances, as illustrated in  FIG.  3 D , the legs  532  and  534  may extend from the base  530  in a plane intersecting the base  530 . In certain instances, the first leg  532  and/or the second  534  can form an angle  8  with the base  530 . In certain instances, the angle  8  can be about 90 degrees, for example, as illustrated in  FIG.  3 D . 
     In various instances, one or more of the staple cartridges of the present disclosure such as, for example, the staple cartridge  40 , the staple cartridge  40 ′, and/or the staple cartridge  2140  can be equipped with retaining features configured to releasably secure “U” shaped staples such as, for example, the “U” shaped staples  50   a - 50   c  within their respective retention slots while a staple cartridge is being maneuvered for positioning relative to tissue. In at least one example, one or more of the staple pushers incorporated into the above-mentioned staple cartridges such as, for example, the staple pushers  160  ( FIG.  1   ), the staple pushers  260  ( FIG.  1 A ), the staple pushers  360  ( FIG.  1 B ), the staple pushers  460  ( FIG.  1 C ), the staple pushers  760  ( FIG.  1 D ), the staple pushers  860  ( FIG.  1 E ), and/or the staple pushers  2160  ( FIG.  2 B ) can be modified to include retaining features, as described in greater detail hereinafter, for releasably securing “U” shaped staples within their respective retention slots. 
       FIG.  3 E  depicts a staple pusher  540  which includes a retaining feature  542  that can be employed to releasably secure a “U” shaped staple  528  within a retention slot of a staple cartridge such as, for example, the staple cartridge  40 , the staple cartridge  40 ′, and/or the staple cartridge  2140 . As illustrated in  FIG.  3 E , in certain instances, a “U” shaped staple  528  can be releasably secured to the staple pusher  540  by positioning a base  530  of the “U” shaped staple between a retaining hook  544  of the retaining feature  542  and a pusher plate comprising a first pusher plate portion  546  and a second pusher plate portion  548 , for example. In at least one example, the first pusher plate portion  546  and the second pusher plate portion  548  may reside on opposite ends of the staple pusher  540 , as illustrated in  FIG.  3 E . 
     In certain instances, the first pusher plate portion  546  may comprise a channel configured to receive a first base portion  550  of the base  530 . The leg  532  may extend from the first base portion  550 . Furthermore, the second pusher plate portion  548  may comprise a channel configured to receive a second base portion  552  of the base  530 . The leg  534  may extend from the second base portion  552 . In certain instances, the retaining hook  544  may receive, or at least partially receive, an intermediate base portion  554  extending between the first base portion  550  and the second base portion  552 , as illustrated in  FIG.  3 E . 
     In certain instances, a “U” shaped staple  528  can be loaded onto a staple pusher  540  by positioning the base  530  of the “U” shaped staple  528  between the retaining hook  544  and the first pusher plate portion  546  and the second pusher plate portion  548 . To load the “U” shaped staple  528  onto a staple pusher  540 , the base  530  can be pressed against a top end  558  of the retaining hook  544  which may cause a springing member  556  to be moved giving way to the base  530  to drop into a final position. In the final position, the first base portion  550  is received by the channel of the first pusher plate portion  546  and the second base portion  552  is received by the channel of the second pusher plate portion  548 , as illustrated in  FIG.  3 E . In certain instances, the springing member  556  is permitted to spring the retaining hook  544  into locking engagement with the base  530  once the base  530  passes the top end  558  into the final position, as illustrated in  FIG.  3 E . 
     The reader will appreciate that the retaining hook  544  can maintain the base  530  in the final position while a staple cartridge carrying the “U” shaped staple  528  is maneuvered to a suitable position relative to tissue. Upon reaching the suitable position, the “U” shaped staple  528  can be ejected from the staple cartridge and formed by an anvil assembly such as, for example the anvil assembly  70  to bond the “U” shaped staple  528  to the tissue. The bond between the formed, or at least forming, “U” shaped staple  528  and the tissue can cause the “U” shaped staple  528  to be pulled free from the retaining hook  544  as the staple cartridge is removed from the stapled tissue, or vice versa. In other words, removing the staple cartridge from the stapled tissue, or vice versa, may cause the base  530  to press against the springing member  556  and move out of locking engagement with the retaining hook  544 . Other releasing mechanisms for releasing the “U” shaped staple  528  from locking engagement with the retaining hook  544  are contemplated by the present disclosure. 
     In various instances, referring primarily to  FIGS.  3 F- 3 H , a “U” shaped staple  528  can be releasably secured to a staple pusher  560 . Like the staple pusher  540 , the staple pusher  560  can releasably secure a “U” shaped staple  528  within a retention slot of a staple cartridge such as, for example, the staple cartridge  40 , the staple cartridge  40 ′, and/or the staple cartridge  2140 . In certain instances, the staple pusher  560  may include a pusher plate  562 . As illustrated in  FIG.  3 G , the pusher plate  562  may comprise a channel  563 . The channel  563  may define an opening  564  comprising a width d 2 , as illustrated in  FIG.  3 G . 
     In certain instances, the width d 2  can be slightly smaller than a width d 1  of the base  530  of the “U” shaped staple  528 . To load the “U” shaped staple  528  onto the staple pusher  560 , the base  530  may be pressed against the pusher plate  562 . In certain instances, the base  530  may be forced through the slightly smaller opening  564 . As illustrated in  FIG.  3 H , the resulting tight fit between the channel and the base  530  may allow the channel  563  to releasably retain at least a portion of the base  530 . In certain instances, walls of the channel  563  can be deformed to accommodate the base  530 . In at least one example, one or more of the walls of the channel  563  can be comprised of a deformable material which may deform under pressure from the base  530  to create a tight fit between the channel  563  and the base  530 . In certain instances, one or more of the walls of the channel  563  can be comprised of one or more deformable soft metals, for example. In certain instances, one or more of the walls of the channel  563  can be comprised of one or more deformable plastics, for example. 
     In certain instances, the width d 1  can be any width selected from a range of about 0.0050 inch, for example, to about 0.0100 inch, for example. In certain instances, the width d 1  can be any width selected from a range of about 0.0060 inch, for example, to about 0.0090 inch, for example. In certain instances, the width d 1  can be any width selected from a range of about 0.0070 inch, for example, to about 0.0080 inch, for example. In certain instances, the width d 1  can be about 0.0079 inch, for example. 
     In certain instances, the width d 2  can be any width selected from a range of about 0.0050 inch, for example, to about 0.0100 inch, for example. In certain instances, the width d 2  can be any width selected from a range of about 0.0055 inch, for example, to about 0.0085 inch, for example. In certain instances, the width d 2  can be any width selected from a range of about 0.0060 inch, for example, to about 0.0075 inch, for example. In certain instances, the width d 2  can be about 0.0069 inch, for example. 
     In certain instances, the ratio of the width d 2  to the width d 1  can be any value selected from a range of about 0.70, for example, to about 0.95, for example. In certain instances, the ratio of the width d 2  to the width d 1  can be any value selected from a range of about 0.75, for example, to about 0.90, for example. In at least one example, the ratio of the width d 2  to the width d 1  is 0.87. In at least one example, the width d 1  is 0.0079 inch and the width d 2  is 0.0069. 
     In various instances, a staple cartridge of the present disclosure such as, for example, the staple cartridge  40 , the staple cartridge  40 ′, and/or the staple cartridge  2140  may comprise retention slots equipped with retention mechanisms configured to releasably secure staples such as, for example, the “U” shaped staple  528  while the staple cartridge is being maneuvered for positioning relative to tissue. For example,  FIGS.  3 I and  3 J  depict a retention slot  570  comprising a retention mechanism  571  which can be employed to releasably secure a “U” shaped staple  528 . 
     In certain instances, referring to  FIG.  3 I , the retention mechanism  571  can be configured to resist release of a “U” shaped staple  528  through an opening  572  of the retention slot  570 . In certain instances, the opening  572  may comprise a first narrow end portion  574  and a second narrow end portion  576 . As illustrated in  FIG.  3 I , the first narrow end portion  574  and the second narrow end portion  578  can be located on opposite ends of the retention slot  570 . 
     In at least one example, as illustrated in  FIG.  3 J , the first narrow end portion  574  comprises a first bendable seal  576  extending, or at least partially extending, across the opening  572  to create the first narrow end portion  574 . Likewise, the second narrow end portion  578  may comprise a second bendable seal  580  extending, or at least partially extending, across the opening  572  to create the second narrow end portion  576 . 
     In certain instances, as illustrated in  FIG.  3 J , the first bendable seal  576  may resist passage of the leg  532  therethrough. In certain instances, the second bendable seal  580  may resist passage of the leg  534  therethrough. To eject the “U” shaped staple  528 , a staple pusher such as, for example, the staple pusher  160  ( FIG.  1   ), the staple pusher  260  ( FIG.  1 A ), the staple pusher  360  ( FIG.  1 B ), the staple pusher  460  ( FIG.  1 C ), the staple pusher  760  ( FIG.  1 D ), the staple pusher  860  ( FIG.  1 E ), and/or the staple pusher  2160  ( FIG.  2 B ) may motivate the “U” shaped staple  528  to exit the retention slot  570 . In such instances, the leg  532  and the leg  534  may be motivated to press against the first bendable seal  576  and the second bendable seal  580 , respectively, to cause the first bendable seal  576  and the second bendable seal  580  to bend to give way for passage of the leg  532  and the leg  534 , respectively. 
     In certain instances, the first bendable seal  576  and/or the second bendable seal  580  may comprise a plurality of bendable tabs  582 . The tabs  582  may resist release of a staple such as, for example, the “U” shaped staple  528  from the retention slot  570 . As illustrated in  FIG.  3 J , a tab  582  may extend across, or at least partially across, the opening  572 , for example. As described above, to eject the “U” shaped staple  528 , a staple pusher may motivate the “U” shaped staple  528  to exit the retention slot  570 . In certain instances, the leg  532  and/or the leg  534  may be motivated to force open a passage between the tabs  582  by causing one or more of the tabs  582  to bend thereby permitting the release of the “U” shaped staple  528 . 
     Referring now to  FIGS.  2 C and  2 D , an end effector  600  is depicted. The end effector  600  is similar in many respects to the end effector  500  ( FIG.  2 A ). Like the end effector  500 , the end effector  600  can be employed with the surgical instrument  10  ( FIG.  2   ). Also, like the end effector  500 , the end effector  600  may comprise an anvil assembly  604  and a cartridge channel  601  which can be configured to receive a staple cartridge such as, for example, the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), and/or the stable cartridge  2140  ( FIG.  3 A ). Furthermore, like the cartridge channel  506  of the end effector  500 , the cartridge channel  601  of the end effector  600  may be fixedly attached to the body portion  12  ( FIG.  2   ) of the surgical instrument  10  and may comprise the distal portion  510  which may deviate from a longitudinal axis defined by the cartridge channel  601 . 
     In certain instances, as illustrated in  FIG.  2 D , the end effector  600  comprises a staple cartridge  602  and an anvil assembly  604 . The anvil assembly  604  is similar in many respects to the anvil assembly  70  ( FIG.  2   ). For example, like the anvil assembly  70 , the anvil assembly  604  can be movable toward a staple cartridge such as, for example, the staple cartridge  602  to capture tissue therebetween in response to actuation of the trigger  32 , for example. 
     Referring again to  FIG.  2 D , the staple cartridge  602  is similar in many respects to the staple cartridge  2140 . For example, like the staple cartridge  2140 , the staple cartridge  602  comprises the tissue contacting portion  2161 , the staple pusher plates  2166   a - 2166   c , the retention slots  2144   a - 2144   c , and the staples  50   a - 50   c . As described above, the tissue contacting portion  2161  includes tissue contacting surfaces  2161   a ,  2161   b , and  2161   c  which are stepped. Also as described above, the tissue contacting surfaces  2161   a ,  2161   b , and  2161   c  include different heights as measured from the datum at the top of the knife channel  2148 . In certain instances, as illustrated in  FIG.  2 D , the tissue contacting surface  2161   c  has a greater height than the tissue contacting surface  2161   b , for example, and the tissue contacting surface  2161   b  has a greater height than the tissue contacting surface  2161   a , for example. 
     Further to the above, the anvil assembly  604  may include a tissue contacting portion  608 . The tissue contacting portion  608  includes tissue contacting surfaces  608   a ,  608   b , and  608   c . Like the tissue contacting surfaces  2161   a - 2161   c , the tissue contacting surfaces  608   a - 608   c  are planar, or at least substantially planar, structures that are substantially parallel to one another, but are not co-planar with one another. Also like the tissue contacting surfaces  2161   a - 2161   c , the tissue contacting surfaces  608   a - 608   c  are stepped. In certain instances, as illustrated in  FIG.  3 D , the stepped arrangement of the tissue contacting surfaces  2161   a ,  2161   b , and  2161   c  can be a mirror image to the stepped arrangement of the tissue contacting surfaces  608   a ,  608   b , and  608   c , respectively. 
     In certain instances, a set of tissue contacting surfaces  608   a - 608   c  is disposed on each side of the knife channel  2148 . The tissue contacting surfaces  608   a - 608   c  include different heights as measured from the datum at the top of the knife channel  2148 , for example. Additionally, the tissue contacting surfaces  608   a  on opposite sides of the knife channel  2148  can be co-planar with one another. Similarly, the tissue contacting surfaces  608   b  on opposite sides of the knife channel  2148  can be co-planar with one another. Furthermore, the tissue contacting surfaces  608   c  on opposite sides of the knife channel  2148  can be co-planar with one another. Although the drawings show planar tissue contacting and/or supporting surfaces  608   a - 608   c , the present disclosure envisions curved or angled tissue contacting surfaces as well as other kinds of tissue contacting surfaces having other shapes and structures. 
     A wall or any other suitable structure interconnects the tissue contacting surfaces  608   a  and  608   b . Similarly, a suitable structure such as a wall interconnects the tissue contacting surfaces  608   b  and  608   c . The walls or interconnecting structures may be oriented orthogonally with respect to the tissue contacting surfaces  608   a - 608   c . The present disclosure, however, contemplates walls or interconnecting structures oriented in different directions such as angled, curved or other configurations. 
     In the embodiment illustrated in  FIG.  2 D , the end effector  600  is depicted in a fully approximated configuration. As illustrated in  FIG.  2 D , the tissue contacting surfaces  608   a - 608   c  of the anvil assembly  602  are stepped such that the most interior tissue contacting surface  608   c  is closest to the staple cartridge  602  while the most exterior tissue contacting surface  608   a  is furthest from the staple cartridge  602 . Likewise the tissue contacting surfaces  2161   a - 2161   c  of the staple cartridge  602  are stepped such that the most interior tissue contacting surface  2161   c  is closest to the anvil assembly  604  while the most exterior tissue contacting surface  2161   c  is furthest from the staple cartridge. 
     The reader will appreciate that as tissue is compressed between the anvil assembly  604  and the staple cartridge  602 , a tissue compression gradient can be created. The tissue captured between the tissue contacting surfaces  2161   c  and  608   c  may experience a greater compression than the tissue captured between the tissue contacting surfaces  2161   b  and  608   b . Also, the tissue captured between the tissue contacting surfaces  2161   b  and  608   b  may experience a greater compression than the tissue captured between the tissue contacting surfaces  2161   a  and  608   a . The resulting tissue compression gradient may cause fluid within the tissue captured between the anvil assembly  604  and the staple cartridge  602  to diffuse or flow outward in a direction away from the knife channel  2148 . 
     Referring now to  FIG.  1 A , a staple drive assembly  200  is depicted. The staple drive assembly  200  is similar in many respects to the staple drive assembly  100  ( FIG.  1   ). Like the staple drive assembly  100 , the staple drive assembly  200  is adapted for use with a surgical stapler such as, for example, the surgical stapler  10  ( FIG.  2   ). Also, like the staple drive assembly  100 , the staple drive assembly  200  can be incorporated into the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), the staple cartridge  602  ( FIG.  2 C ), and/or the stable cartridge  2140  ( FIG.  3 A ), for example. 
     As illustrated in  FIG.  1 A , the staple drive assembly  200  includes an actuation sled  210  and at least one staple pusher arrangement or system  260 . The actuation sled  210  includes a base  212 , a first camming member  220 , a second camming member  240 , and a guide member  250 . The first camming member  220  and the second camming member  240  can be located on opposite sides of the guide member  250 . The first and second camming members  220 ,  240  include respective first or leading cam wedges  222 ,  242  and respective second or trailing cam wedges  224 ,  244 , for example. 
     The actuation sled  210  is translatable to motivate at least one staple pusher arrangement or system  260  to eject staples such as, for example, the staples  50   a - 50   c , the staples  520 , and/or the staples  528  from a staple cartridge into tissue captured by the surgical instrument  10 . The staple pusher  260  is similar in many respects to the staple pusher  160 . For example, like the staple pusher  160 , the staple pusher  260  includes staggered pusher plates  266   a - 266   c  which are similar in many respects to the staggered pusher plates  166 . Also, like the staple pusher  160 , the staple pusher  260  comprises a camming member  164  which is configured to couple the middle pusher plate  266   b  and the outboard pusher plate  266   c , as illustrated in  FIG.  1 A . 
     However, unlike the staple pusher  160 , the staple pusher  260  lacks the camming member  162 . Accordingly, the inboard pusher plate  266   a  of the pusher plate  260  can be moved independently relative to the middle and outboard pusher plates  266  which are coupled by the camming member  164 . In certain instances, the inboard pusher plate  266   a  may comprise a separate camming member  262 , as illustrated in  FIG.  1 A , which can be engaged with a leading cam wedge such as, for example, the cam wedge  222  as the actuation sled  210  is translated to motivate the at least one staple pusher arrangement or system  260  to eject staples. 
     In certain instances, as illustrated in  FIG.  1 A , the leading cam wedges  222 ,  242  may comprise steeper drive angles in comparison to the trailing cam wedges  224 ,  244 , for example. In such instances, as the actuation sled  210  is advanced against the staple pusher  260 , the camming member  262  may be elevated faster than the camming member  164 . Accordingly, the inboard pusher plate  266   a , which is coupled to the camming member  262 , can be elevated faster than the outboard pusher plate  266   c  and middle pusher plate  266   b , which are coupled to the camming member  164 . A staple driven by the faster elevated inboard pusher plate  266   a  may be fully-formed faster than simultaneously ejected staples which are driven by the slower elevated outboard pusher plate  266   c  and middle pusher plate  266   b , for example. 
     In certain instances, as illustrated in  FIG.  1 A , the leading cam wedges  222 ,  242  may terminate higher than the trailing cam wedges  224 ,  244 , for example. Said another way, proximal ends of the leading cam wedges  222 ,  242  may comprise greater vertical heights than proximal ends of the trailing cam wedges  224 ,  244 , for example. In such instances, as the actuation sled  210  is advanced against the staple pusher  260 , the camming member  262  may be elevated higher than the camming member  164 . Accordingly, the inboard pusher plate  266   a , which is coupled to the camming member  262 , can be elevated higher than the outboard pusher plate  266   c  and middle pusher plate  266   b , which are coupled to the camming member  164 . A staple driven by the higher elevated inboard pusher plate  266   a  may be compressed to a greater degree in a fully-formed configuration than similarly sized and simultaneously ejected staples that are driven by the lower elevated outboard pusher plate  266   c  and middle pusher plate  266   b , for example. 
     In certain instances, the ratio of the drive angles of the trailing cam wedges  224 ,  244  to the drive angles of the leading cam wedges  222 ,  242 , respectively, can be selected from a range of about 0.7, for example, to about 0.9, for example. In at least one example the ratio can be about 0.8, for example. 
     In certain instances, the ratio of the vertical heights of the proximal ends of the trailing cam wedges  224 ,  244  to the vertical heights of the proximal ends of the leading cam wedges  222 ,  242 , respectively, can be selected from a range of about 0.7, for example, to about 0.9, for example. In at least one example the ratio can be about 0.8, for example. 
     In certain instances, as illustrated in  FIG.  1 A , the leading cam wedges  222 ,  242  may terminate prior to the trailing cam wedges  224 ,  244 , for example. Said another way, the trailing cam wedges  224 ,  244  may extend proximally beyond the leading cam wedges  222 ,  242 . In such instances, as the actuation sled  210  is advanced against a staple pusher  260 , the camming member  164  of the staple pusher  260  may be driven by a trailing cam wedge for a longer period of time than the camming member  262  of the staple pusher  260  is driven by a leading cam wedge, for example. Accordingly, staples deployed by the longer driven middle pusher plate  266   b  and outboard pusher plate  266   c  can be fully-formed after a simultaneously ejected staple which is deployed by the shorter driven inboard pusher plate  266   c  is fully-formed, for example. 
     The reader will appreciate that the independent movement of the inboard pusher plate  266   a  from the middle pusher plate  266   b  and outboard pusher plate  266   c  in response to the advancement of the actuation sled  210  against the staple pusher  260  allows a staple driven by the inboard pusher plate  266   a  to be fully-formed faster and/or to a greater final compression than simultaneously ejected staples that are driven by the middle pusher plate  266   b  and outboard pusher plate  266   c.    
     The reader will also appreciate that the time lag between the formation of a staple ejected by the inboard pusher plate  266   a  and staples ejected by the middle pusher plate  266   b  and the outboard pusher plate  266   c  may provide a greater opportunity for outward fluid diffusion through tissue receiving such staples. Furthermore, incorporation of the staple drive assembly  200  into a cartridge assembly  602  of the end effector  600  ( FIG.  2 C ) may further increase the opportunity available for outward fluid diffusion by combining the faster ejection and/or complete formation of staples ejected by the inboard pusher plate  266   a  with the compression gradient generated by the anvil assembly  604  and the staple cartridge  602 , for example. 
     Referring now to  FIG.  1 B , a staple drive assembly  300  is depicted. The staple drive assembly  300  is similar in many respects to the staple drive assembly  100  ( FIG.  1   ). Like the staple drive assembly  100 , the staple drive assembly  300  is adapted for use with a surgical stapler such as, for example, the surgical stapler  10 . Also, like the staple drive assembly  100 , the staple drive assembly  300  can be incorporated into the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), the staple cartridge  602  ( FIG.  3 A ) and/or the stable cartridge  2140  ( FIG.  3 A ), for example. However, unlike the staple drive assembly  100 , the staple drive assembly  300  is configured to simultaneously deploy three inversely staggered staples  50   a - 50   c . The three inversely staggered staples  50   a - 50   c  are arranged such that the inner most staple  50   c  is in a proximal, or at least partially proximal, position to the middle staple  50   b  with respect to the distal portion of the staple cartridge and the middle staple  50   b  is in a proximal, or at least partially proximal, position to the outer most staple  50   a  with respect to the distal portion of the staple cartridge. Furthermore, the inner most staple  50   c  comprises a smaller fully-formed height than the middle staple  50   b  and the middle staple  50   b  comprises a smaller fully-formed height than the outer most staple  50   a , for example. 
     As illustrated in  FIG.  1 B , the staple drive assembly  300  includes an actuation sled  310  and at least one staple pusher arrangement or system  360 . The at least one staple pusher arrangement or system  360  includes inversely staggered pusher plates  366   a - 366   c . The actuation sled  310  includes a base  312 , a first camming member  320 , a second camming member  340 , and a guide member  350 . The first camming member  320  and the second camming member  340  can be located on opposite sides of the guide member  350 . The first and second camming members  320 ,  340  include respective first or leading cam wedges  322 ,  342  and respective second or trailing cam wedges  324 ,  344 , for example. 
     Unlike the actuation sled  110  of the staple drive assembly  100 , the actuation sled  310  of the staple drive assembly  300  comprises outward leading cam wedges and inward trailing cam wedges corresponding to the inversely staggered pusher plates  366   a - 366   c . For example, as illustrated in  FIG.  1 B , the leading cam wedge  322  is laterally spaced further away from the guide member  350  than the trailing cam wedge  324  and the leading cam wedge  342  is laterally spaced further away from the guide member  350  than the trailing cam wedge  344 . 
     Further to the above, as illustrated in  FIG.  1 B , the pusher plates  366   a - 366   c  of the staple pusher  360  of the staple drive assembly  300  are inversely staggered such that an outboard pusher plate  366   c , which is furthest from the knife channel  2148 , is closer to a distal portion of a staple cartridge that incorporates the staple pusher  360  than a middle pusher plate  366   b  and the middle pusher plate  366   b  is closer to the distal portion of the staple cartridge than the inboard pusher plate  366   a , which is closest to the knife channel  2148 , for example. Said another way, the inboard pusher plate  366   a  lags behind the middle pusher plate  366   b  and the middle pusher plate  366   b  lags behind the outboard pusher plate  366   c , for example. 
     Further to the above, as illustrated in  FIG.  1 B , the inboard pusher plate  366   a  comprises a greater vertical height than the middle pusher plate  366   b  and the middle pusher plate  366   b  comprises a greater vertical height the outboard pusher plate  366   c . The inboard pusher plate  366   a  deploys a first staple  50   c  comprising a first unformed height. The middle pusher plate  366   b  deploys a second staple  50   b  comprising a second unformed height greater than the first unformed height of the first staple  50   c . The outboard pusher plate  366   c  deploys a third staple  50   a  comprising a third unformed height greater than the second unformed height of the second staple  50   b , for example. Furthermore, the first staple  50   c  comprises a smaller fully-formed height than the second staple  50   b  and the second staple  50   b  comprises a smaller fully-formed height than the third staple  50   a , for example. Like the inversely staggered pusher plates  366   a - 366   c , the staples  50   a ,  50   b , and  50   c , which are simultaneously deployed by the pusher plates  366   c ,  366   b , and  366   a  respectively, comprise an inversely staggered arrangement such that the third staple  50   a  is closer to a distal portion of a staple cartridge that incorporates the staple pusher  360  than the second staple  50   b  and the second staple  50   b  is closer to a distal portion of the staple cartridge than the first staple  50   c.    
     Referring now to  FIGS.  1 C and  1 D , staple drive assemblies  400  and  700  are depicted. The staple drive assemblies  400  ( FIG.  1 C ) and  700  ( FIG.  1 D ) are similar in many respects to the staple drive assembly  100  ( FIG.  1   ). Like the staple drive assembly  100 , the staple drive assemblies  400  and  700  are adapted for use with a surgical stapler such as, for example, the surgical stapler  10 . Also, like the staple drive assembly  100 , the staple drive assemblies  400  and  700  can be incorporated into the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), the staple cartridge  602  ( FIG.  2 C ), and/or the stable cartridge  2140  ( FIG.  3 A ), for example. 
     As illustrated in  FIG.  1 C , the staple drive assembly  400  includes an actuation sled  410  and at least one staple pusher arrangement or system  460 . The actuation sled  410  includes a base  412 , a first camming member  420 , a second camming member  440 , and a guide member  450 . The first camming member  420  and the second camming member  440  can be located on opposite sides of the guide member  450 . The first and second camming members  420 ,  440  include respective first or leading cam wedges  422 ,  442  and respective second or trailing cam wedges  424 ,  444 , for example. 
     The actuation sled  410  is translatable to motivate at least one staple pusher arrangement or system  460  to eject staples such as, for example, the staples  50   a - 50   c , the staples  520 , and/or the staples  528  from a staple cartridge into tissue captured by the surgical instrument  10 . The staple pusher  460  is similar in many respects to the staple pusher  160  arrangement or system. For example, like the staple pusher  160 , the staple pusher  460  comprises three pusher plates  466   a - 466   c . Also, like the staple pusher  160 , the staple pusher  460  comprises camming members or portions  162  and  164  which couple the pusher plates  466   a - 466   c , as illustrated in  FIG.  1 C . 
     The pusher plates  466   a - 466   c  are similar in many respects to the pusher plates  166 . For example, like the pusher plates  166 , the pusher plates  466  are laterally spaced apart such that an inboard pusher plate  466   a  is closest to the knife channel  2148  and an outboard pusher plate  466   c  is furthest from the knife channel  2148 , as illustrated in  FIG.  1 C . A middle pusher plate  466   b  is situated between the inboard pusher plate  466   a  and the outboard pusher plate  466   c , for example. 
     Further to the above, as illustrated in  FIG.  1 C , the pusher plates  466   a - 466   c  of the staple pusher  460  of the staple drive assembly  400  are arranged such that the outboard pusher plate  466   c  and the middle pusher plate  466   b  are laterally aligned with each other. Said another way, the outboard pusher plate  466   c  and the middle pusher plates  466   b  are equidistant from a distal portion of a staple cartridge that incorporates the staple pusher  460 , for example. In addition, the inboard pusher plate  466   a  is closer to the distal portion of the staple cartridge than the outboard pusher plate  466   c  and the middle pusher plates  466   b , for example. In certain instances, the outboard pusher plate  466   c  and the middle pusher plate  466   b  equally lag in position proximally behind the inboard pusher plate  466 , for example. 
     Further to the above, as illustrated in  FIG.  1 C , the inboard pusher plate  466   a  comprises a greater vertical height than the middle pusher plate  466   b  and, similarly, the middle pusher plate  466   b  comprises a greater height the outboard pusher plate  466   c . The inboard pusher plate  466   a  deploys a first staple  50   c  comprising a first unformed height. The middle pusher plate  466   b  deploys a second staple  50   b  comprising a second unformed height greater than the first unformed height of the first staple  50   c . The outboard pusher plate  466   c  deploys a third staple  50   a  comprising a third unformed height greater than the second unformed height of the second staple  50   b , for example. Furthermore, the first staple  50   c  comprises a smaller fully-formed height than the second staple  50   b  and the second staple  50   b  comprises a smaller fully-formed height than the third staple  50   a , for example. Like the pusher plates  466   a - 466   c , the staples  50   a ,  50   b , and  50   c , which are simultaneously deployed by the pusher plates  466   c ,  466   b , and  466   a  respectively, are arranged such that the third staple  50   a  and the second staple  50   b  equally lag in position proximally behind the first staple  50   c , as illustrated in  FIG.  1 C . 
     In certain instances, the difference in formed height between the staples  50   a - 50   c  may create a compression gradient, as described above, that allows fluid diffusion in an outward direction away from the knife channel  2148 . Furthermore, positioning the inboard pusher plate  466   a  slightly ahead in position relative to the middle pusher plate  466   b  and outboard pusher plate  466   c  may cause an inner row of staples  50   c  to be deployed slightly ahead of a middle row of staples  50   b  and an outer row of staples  50   a . For example, the inner row of staples  50   c  can be deployed one staple ahead of the middle row of staples  50   b  and the outer row of staples  50   a.    
     The lag in the deployment of the middle row of staples  50   b  and the outer row of staples  50   a  relative to the inner row of staples  50   c  may cause a lag in the application of tissue compression as the firing action of the staple pusher  460  moves from the inner to the outer staple rows. The lag in the application of tissue compression may provide additional time for the fluid diffusion through the tissue captured between the inner row of staples  50   c  and the middle row of staples  50   b.    
     In certain instances, the lateral alignment of the middle pusher plate  466   b  and the outboard pusher plate  466   c  may cause laterally aligned staples  50   b  and staples  50   a  of a middle row of staples  50   b  and an outer row of staples  50   a , respectively, to be simultaneously formed. In certain instances, the simultaneous deployment of the laterally aligned staples  50   b  and staples  50   a  can provide a better grip onto tissue portions, intended for the lesser compression, to ensure stability in the outer row of staples  50   a  and the middle row of staples  50   b  as the staple pusher  460  is translated distally. 
     Further to the above, the lateral alignment of the staples  50   a  and  50   b  may cause the staple gaps between the staples  50   a  of the row of staples  50   a  and the staple gaps between the staples  50   b  of the row of staples  50   b  to be laterally aligned. In certain instances, the lateral alignment described herein can be complete lateral alignment. In other instances, the lateral alignment described herein can be partial lateral alignment. In any event, the lateral alignment of the staples  50   a  and  50   b  may create, or at least substantially create, channels for fluid diffusion through the laterally aligned staple gaps of the rows of staples  50   a  and  50   b . In certain instances, as described above, the staples  50   c  are staggered with respect to the laterally aligned staples  50   a  and  50   b . In such instances, the staples  50   c  can be laterally positioned with respect to the staple gaps the row of staples  50   a  and the staple gaps of the row of staples  50   b . Such a staggered arrangement of the staples  50   c  with respect to the laterally aligned staples  50   a  and  50   b  may ensure hemostasis along the stapled tissue. 
     As illustrated in  FIG.  1 D , the staple drive assembly  700  includes an actuation sled  710  and at least one staple pusher arrangement or system  760 . The actuation sled  710  includes a base  712 , a first camming member  720 , a second camming member  740 , and a guide member  750 . The first camming member  720  and the second camming member  740  can be located on opposite sides of the guide member  750 . The first and second camming members  720 ,  740  include respective first or leading cam wedges  722 ,  742  and respective second or trailing cam wedges  724 ,  744 , for example. 
     The actuation sled  710  is translatable to motivate at least one staple pusher arrangement or system  760  to eject staples such as, for example, the staples  50   a - 50   c , the staples  520 , and/or the staples  528  from a staple cartridge into tissue captured by the surgical instrument  10 . The staple pusher  760  is similar in many respects to the staple pusher  160 . For example, like the staple pusher  160 , the staple pusher  760  comprises three pusher plates  766   a - 766   c . Also, like the staple pusher  160 , the staple pusher  760  comprises the camming members or portions 162  and  164  which are configured to couple the pusher plates  766   a - 766   c , as illustrated in  FIG.  1 D . 
     The pusher plates  766   a - 766   c  are similar in many respects to the pusher plates  166 . For example, like the pusher plates  166 , the pusher plates  766   a - 766   c  are laterally spaced apart such that an inboard pusher plate  766   a  is closest to the knife channel  2148  and an outboard pusher plate  766   c  is furthest from the knife channel  2148 , as illustrated in  FIG.  1 D . A middle pusher plate  766   b  is situated between the inboard pusher plate  766   a  and the outboard pusher plates  766   c , for example. 
     Further to the above, as illustrated in  FIG.  1 D , the pusher plates  766   a -  766   c  of the staple pusher  760  of the staple drive assembly  700  are arranged such that the inboard pusher plate  766   a  and the middle pusher plate  766   b  are laterally aligned with each other. Said another way, the inboard pusher plate  766   a  and the middle pusher plate  766   b  are equidistant from a distal portion of a staple cartridge that incorporates the staple pusher  760 , for example. In addition, the outboard pusher plate  766   c  is further away from the distal portion of the staple cartridge than the inboard pusher plate  766   a  and the middle pusher plate  766   b , for example. In other words, the outboard pusher plate  766   c  lags in position proximally behind the inboard pusher plate  766   a  and the middle pusher plate  766   b , for example. Said another way, the inboard pusher plate  766   a  and the middle pusher plate  766   b  are equally ahead in position distally relative to the outboard pusher plate  766   c . 
     Further to the above, as illustrated in  FIG.  1 D , the inboard pusher plate  766   a  comprises a greater vertical height than the middle pusher plate  766   b  and the middle pusher plate  766   b  comprises a greater vertical height than the outboard pusher plate  766   c . The inboard pusher plate  766   a  deploys a first staple  50   c  comprising a first unformed height. The middle pusher plate  766   b  deploys a second staple  50   b  comprising a second unformed height greater than the first unformed height of the first staple  50   c . The outboard pusher plate  766   c  deploys a third staple  50   a  comprising a third unformed height greater than the second unformed height of the second staple  50   b , for example. Furthermore, the first staple  50   c  comprises a smaller fully-formed height than the second staple  50   b  and the second staple  50   b  comprises a smaller fully-formed height than the third staple  50   a , for example. Like the pusher plates  766   a - 766   c , the staples  50   a ,  50   b , and  50   c , which are simultaneously deployed by the pusher plates  766   c ,  766   b , and  766   a  respectively, are arranged such that the first staple  50   c  and the second staple  50   b  are equally ahead in position distally relative to the third staple  50   a , as illustrated in  FIG.  1 D . 
     In certain instances, the difference in formed height between the staples  50   a - 50   c  may create a compression gradient, as described above, that allows fluid diffusion in an outward direction away from the knife channel  2148 . Furthermore, positioning the outboard pusher plate  766   c  slightly behind in position relative to the middle pusher plate  766   b  and the inboard pusher plate  766   a  may cause an outer row of staples  50   a  to be deployed slightly after a middle row of staples  50   b  and an inner row of staples  50   c . For example, the outer row of staples  50   a  can be deployed one staple behind the middle row of staples  50   b  and the inner row of staples  50   c.    
     The lag in the deployment of the outer row of staples  50   a  relative to the middle row of staples  50   b  and the inner row of staples  50   c  may cause a lag in the application of tissue compression as the firing action of the staple pusher  460  moves from the inner to the outer staple rows. The lag in the application of tissue compression may provide additional time for the fluid diffusion through the captured tissue between the middle row of staples  50   b  and the outer row of staples  50   a.    
     In certain instances, the lateral alignment of the middle pusher plate  766   b  and the inboard pusher plate  766   a  may cause laterally aligned staples  50   b  and staples  50   c  of a middle row of staples  50   b  and an inner row of staples  50   c , respectively, to be simultaneously formed. In certain instances, the simultaneous deployment of the laterally aligned middle staples  50   b  and inner staples  50   c  can provide a better grip onto tissue portions captured by the inner row of staples  50   c  and the middle row of staples  50   a  as the staple pusher  460  is translated distally. 
     Further to the above, the lateral alignment of the staples  50   c  and  50   b  may cause the staple gaps between the staples  50   c  of the row of staples  50   c  and the staple gaps between the staples  50   b  of the row of staples  50   b  to be laterally aligned. In certain instances, the lateral alignment described herein can be complete lateral alignment. In other instances, the lateral alignment described herein can be partial lateral alignment. In any event, the lateral alignment of the staples  50   c  and  50   b  may create, or at least substantially create, channels for fluid diffusion through the laterally aligned staple gaps of the rows of staples  50   c  and  50   b . In certain instances, as described above, the staples  50   a  are staggered with respect to the laterally aligned staples  50   c  and  50   b . In such instances, the staples  50   a  can be laterally positioned with respect to the staple gaps the row of staples  50   c  and the staple gaps of the row of staples  50   b . Such a staggered arrangement of the staples  50   a  with respect to the laterally aligned staples  50   c  and  50   b  may ensure hemostasis along the stapled tissue. 
     Referring now to  FIG.  1 E , a staple drive assembly  800  is depicted. The staple drive assembly  800  is similar in many respects to the staple drive assembly  100  ( FIG.  1   ). Like the staple drive assembly  100 , the staple drive assembly  800  is adapted for use with a surgical stapler such as, for example, the surgical stapler  10 . Also, like the staple drive assembly  100 , the staple drive assembly  800  can be incorporated into the stable cartridge  40  ( FIG.  2   ), the stable cartridge  40 ′ ( FIG.  3   ), the staple cartridge  602  ( FIG.  2 C ), and/or the stable cartridge  2140  ( FIG.  3 A ), for example. 
     As illustrated in  FIG.  1 E , the staple drive assembly  800  includes an actuation sled  810  and at least one staple pusher arrangement or system  860 . The actuation sled  810  includes a base  812 , a first camming member  820 , a second camming member  840 , and a guide member  850 . The first camming member  820  and the second camming member  840  can be located on opposite sides of the guide member  850 . The first camming member  820  includes a first or leading cam wedge  822  and a second or trailing cam wedge  824 . The second camming member  840  includes a first or leading cam wedge  842  and a second or trailing cam wedge  844 . In certain instances, the first camming member  820  can be laterally out of alignment with the second camming member  840 . In at least one example, as illustrated in  FIG.  1 E , the second camming member  840  lags in position proximally behind the first camming member  820  a distance “d 1 ”. 
     The actuation sled  810  is translatable to motivate a plurality of staple pushers  860  to eject staples such as, for example, the staples  50   a - 50   c , the staples  520 , and/or the staples  528  from a staple cartridge into tissue captured by the surgical instrument  10 . In certain instances, the staple pushers  860  are arranged on opposite sides of the knife channel  2148 . For example, a first staple pusher  860   a  can be positioned on a first side  2148   a  of the knife channel  2148  and a second staple pusher  860   b  can be positioned on a second side  2148   b , opposite the first side  2148   a , of the knife channel  2148 . The first staple pusher  860   a  and the second staple pusher  860   b  can be equidistant from a distal portion of a staple cartridge that incorporates the staple pushers  860 . 
     In certain instances, the lag between the first camming member  820  and the second camming member  840  causes the first camming member  820  to engage the first staple pusher  860   a  before the second camming member  840  engages the second staple pusher  860   b . In such instances, the staples driven by the first camming member  820  are ejected, or at least partially ejected, before the staples driven by the second camming member  840 . The reader will appreciate that the lag between the engagement of the first camming member  820  with the first staple pusher  860   a  and the engagement of the second camming member  840  with the second staple pusher  860   b  can depend, at least in part, on the distance “d 1 ”. 
     In certain instances, the displacement of the first camming member  820  out of alignment with the second camming member  840  may reduce the force required to eject the staples  50   a - 50   c . As the actuation sled  810  is translated, the camming member  820  may engage the first staple pusher  860   a  and eject, or at least partially eject, the staples  50   a - 50   c  of the first staple pusher  860   a  before the camming member  840  engages the second staple pusher  860   b , for example. 
     In certain instances, the staples  50   a - 50   c  of the second staple pusher  860   b  can be in a first phase of ejection while the staples  50   a - 50   c  of the first staple pusher  860   a  are in a second later phase of ejection. In certain instances, driving the staples  50   a - 50   c  through the first phase of ejection requires a lesser force than driving the staples  50   a - 50   c  through the second phase of ejection. For example, the first phase of ejection may comprise elevating the staples  50   a - 50   c  to penetrate tissue captured between an anvil assembly and a tissue cartridge and the second phase of ejection may comprise forming the staples  50   a - 50   c  against the anvil assembly. 
     In certain instances, the lag between the first camming member  820  and the second camming member  840  can be configured to cause the first camming member  820  to be engaged with the first staple pusher  866   a  in the second phase of ejection while the second camming member  840  is engaged with the second staple pusher  866   b  in the first phase of ejection. In at least one example, as the actuation sled  810  is translated, the first camming member  820  and the second camming member  840  may alternate between first phases of ejection and second phases of ejection. Accordingly, the force required to translate the actuation sled  820  can be the sum of the force required at a first phase of ejection and at second phase of ejection. The reader will appreciate that if the first camming member  820  and the second camming member  840  are aligned, the force required to translate the actuation sled  810  will be alternated between the total force required at two first phases of ejection and the total force required at two second phases of ejection. 
     Further to the above, the staple pusher  860  is similar in many respects to the staple pusher  160 . For example, like the staple pusher  160 , the staple pusher  860  includes staggered pusher plates  866   a - 866   c  which are similar in many respects to the staggered pusher plates  166 . Also, like the staple pusher  160 , the staple pusher  860  comprises the camming members  162  and  164  which are configured to couple the pusher plates  866   a - 866   c , as illustrated in  FIG.  1 E . 
     The pusher plates  866   a - 866   c  are similar in many respects to the pusher plates  166 . For example, like the pusher plates  166 , the pusher plates  866   a - 866   c  are laterally spaced apart such that an inboard pusher plate  866   a  is closest to the knife channel  2148  and an outboard pusher plate  866   c  is furthest from the knife channel  2148 , as illustrated in  FIG.  1 E . The middle pusher plate  866   b  is situated between the inboard pusher plate  866   a  and outboard pusher plates  866   c , for example. 
     Further to the above, as illustrated in  FIG.  1 E , the inboard pusher plate  866   a  comprises a greater vertical height than the middle pusher plate  866   b  and the middle pusher plate  866   b  comprises a greater vertical height the outboard pusher plate  866   c . The inboard pusher plate  866   a  deploys a first staple  50   c  comprising a first unformed height. The middle pusher plate  866   b  deploys a second staple  50   b  comprising a second unformed height greater than the first unformed height of the first staple  50   c . The outboard pusher plate  866   c  deploys a third staple  50   a  comprising a third unformed height greater than the second unformed height of the second staple  50   b , for example. Furthermore, the first staple  50   c  comprises a smaller fully-formed height than the second staple  50   b  and the second staple  50   b  comprises a smaller fully- formed height than the third staple  50   a , for example. 
     The entire disclosures of: 
     U.S. Pat. No. 5,403,312, entitled ELECTROSURGICAL HEMOSTATIC DEVICE, which issued on Apr. 4, 1995; 
     U.S. Pat. No. 7,000,818, entitled SURGICAL STAPLING INSTRUMENT HAVING SEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, which issued on Feb. 21, 2006; 
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     U.S. Pat. No. 8,393,514, entitled SELECTIVELY ORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, which issued on Mar. 12, 2013; 
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     U.S. Patent Application Publication No. 2010/0264194, entitled SURGICAL STAPLING INSTRUMENT WITH AN ARTICULATABLE END EFFECTOR, filed Apr. 22, 2010, now U.S. Pat. No. 8,308,040, are hereby incorporated by reference herein. 
     Although the various embodiments of the devices have been described herein in connection with certain disclosed embodiments, many modifications and variations to those embodiments may be implemented. Also, where materials are disclosed for certain components, other materials may be used. Furthermore, according to various embodiments, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to perform a given function or functions. The foregoing description and following claims are intended to cover all such modification and variations. 
     The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application. 
     Preferably, the invention described herein will be processed before surgery. First, a new or used instrument is obtained and if necessary cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in the medical facility. 
     While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains. 
     Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.