Patent Publication Number: US-9844370-B2

Title: Varying tissue compression with an anvil configuration

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/427,796, filed on Apr. 22, 2009, which claims the benefit of, and priority to, U.S. Provisional Patent Application Ser. No. 61/051,916, filed on May 9, 2008, the entire contents of each of these prior applications are incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to surgical fastener applying apparatus. More particularly, the present disclosure relates to a tool assembly for use with a surgical fastener applying apparatus, and methods of manufacturing the same, to apply a plurality of surgical fasteners to tissue with varying compressive forces. 
     2. Background of the Related Art 
     Many varieties of surgical fastener applying apparatus are known in the art, some of which are specifically adapted for use in various surgical procedures including, but not limited to, end-to-end anastomosis, circular end-to-end anastomosis, open gastrointestinal anastomosis, endoscopic gastrointestinal anastomosis, and transverse anastomosis. Suitable examples of apparatus which may be used during the course of these procedures can be seen in U.S. Pat. Nos. 5,915,616; 6,202,914; 5,865,361; and 5,964,394. 
     In general, a surgical fastener applying apparatus will include an anvil that is approximated relative to a surgical fastener cartridge during use. The anvil includes depressions that are aligned with, and/or are in registration with, slots defined in the surgical fastener cartridge, through which the surgical fasteners will emerge. To effectuate formation, the surgical fasteners emerge from the surgical fastener cartridge and are driven against the anvil. The surgical fastener cartridge typically has one or more rows of surgical fasteners that are disposed laterally outward of a slot that is configured to accommodate a knife, or other such cutting element, such that tissue can be simultaneously severed and joined together at a cut-line. Depending upon the particular surgical fastener applying apparatus, the rows of fasteners may be arranged in a linear, non-linear, e.g. circular, semi-circular, or other configuration. 
     Various types of surgical fasteners are well known in the art including, but not limited to, unitary fasteners and two-part fasteners. Unitary fasteners generally include a pair of legs that are adapted to penetrate tissue and connected by a backspan from which they extend. In use, subsequent to formation, certain types of unitary fasteners have a “B” shaped configuration. Typically, the two-part fastener includes legs that are barbed and connected by a backspan. The legs are engaged and locked into a separate retainer piece that is usually located in the anvil. In use, the two-part fastener is pressed into the tissue so that the barbs penetrate the tissue and emerge from the other side where they are then locked into the retainer piece. The retainers prevent the two-part fastener from dislodging from the tissue. The two-part fasteners are not intended to be unlocked or removable. For this reason, they are generally made of a bioabsorbable material. 
     A common concern in each of the procedures mentioned above is hemostasis, or the rate at which bleeding of the target tissue is stopped. It is commonly known that by increasing the amount of pressure applied to a wound, the flow of blood can be limited, thereby decreasing the time necessary to achieve hemostasis. To this end, conventional surgical fastener applying apparatus generally apply two or more rows of fasteners about the cut-line to compress the surrounding tissue in an effort to stop any bleeding and to join the cut tissue together. Each of the surgical fasteners will generally apply a compressive force to the tissue that is sufficient to effectuate hemostasis. However, applying too much pressure can result in a needless reduction in blood flow to the tissue surrounding the cut-line, resulting in an elevated level of necrosis, a slower rate of healing, and/or a greater recovery period. 
     Consequently, it would be advantageous to provide a surgical fastener applying apparatus capable of limiting the flow of blood in the tissue immediately adjacent the cut-line to effectuate hemostasis and wound closure, while maximizing blood flow in the surrounding tissue to facilitate healing. Additionally, when tissue is clamped and compressed between the anvil and cartridge, some of the fluid retained within the tissue is squeezed out, which results in greater compression at the portions of the cartridge and the anvil adjacent the cut-line when compared to the lateral edges. It may also be desirable to cut and fasten across tissue that varies in thickness. It would therefore be advantageous to provide fasteners and surgical fastener applying apparatus that are better adapted to apply variable compressive forces to tissue in the interests of addressing these concerns. 
     SUMMARY 
     The present disclosure relates to surgical fastener applying apparatus that apply variable compression to tissue, and/or accommodate tissue of varying thickness. More specifically, surgical fastener applying apparatus in accordance with the principles of the present disclosure act to limit the flow of blood through tissue immediately adjacent a cut-line formed therein to effectuate hemostasis, while maximizing the flow of blood through tissue more removed from the cut-line to limit unnecessary necrosis. 
     In one aspect of the present disclosure, a surgical fastener applying apparatus is disclosed that includes an anvil member having a tissue contacting surface, a surgical fastener cartridge, or cartridge member, that is movably coupled to the anvil member, and a sled. 
     The cartridge member extends along a longitudinal axis, and is movably coupled to the anvil member. The cartridge member includes a plurality of surgical fasteners and a plurality of pushers that are operatively associated with the plurality of surgical fasteners. Each pusher includes a base portion and a plurality of pusher plates that extend from the base portion such that adjacent pusher plates define an acute angle therebetween. 
     The aforementioned sled is operably engagable with the plurality of pushers such that engagement of the sled with the pushers urges the surgical fasteners towards the anvil member such that a first row of surgical fasteners applies a first compressive force to tissue disposed between the anvil member and the cartridge member, and a second row of surgical fasteners applies a second, different compressive force to the tissue disposed between the anvil member and the cartridge member. 
     The pushers and the surgical fasteners may be configured and dimensioned such that the compressive forces are varied along an axis that is transverse to the longitudinal axis of the cartridge member. Additionally, or alternatively, the pushers and the surgical fasteners may be configured and dimensioned such that the compressive forces applied to the tissue decrease outwardly relative to a centerline of the cartridge member such that blood flow through the tissue nearer to the centerline of the cartridge member is less than blood flow through the tissue further from the centerline of the cartridge member. 
     Each pusher plate extends from the base portion to define a different length. For example, the pusher plates positioned nearer to a centerline of the cartridge member may be shorter than those positioned further from the centerline. 
     In one embodiment of the surgical fastener applying apparatus, the plurality of pusher plates includes a first pusher plate, a second pusher plate, and a third pusher plate. In this embodiment, the first pusher plate is positioned nearest to the centerline of the cartridge member, the second pusher plate is positioned outwardly of the first pusher plate and further from the centerline, and the third pusher plate is positioned outwardly of the second pusher plate and furthest from the centerline. The first pusher plate extends from the base portion to define a first length, the second pusher plate extends from the base portion to define a second length, and the third pusher plate extends from the base portion to define a third length, wherein the third length is greater than the second length, and the second length is greater than the first length. 
     The pusher plates are connected to the base portion at a hinge member, e.g., a living hinge. The hinge member is configured to allow the pusher plates to diverge as the pushers are driven towards the anvil member by the sled such that the angles described between adjacent pusher plates are increased. 
     The disclosed cartridge member includes a top wall having a plurality of retention slots formed therein that are configured and dimensioned to allow the surgical fasteners to pass therethrough during ejection from the cartridge member. Each fastener retention slot is aligned with a corresponding pocket formed in the tissue contacting surface of the anvil member. The fastener pockets formed in the tissue contacting surface of the anvil member may be arranged such that each fastener retention slot is aligned with a plurality of corresponding fastener pockets to reduce any likelihood of improper surgical fastener formation. In one embodiment, it is contemplated that the anvil member may be formed from a plurality of plates that are secured together. 
     The surgical fasteners are positioned within the cartridge member to define a predetermined distance between penetrating tips thereof and the corresponding pocket formed in the tissue contacting surface of the anvil member. The surgical fasteners positioned nearer to a centerline of the cartridge member may be shorter than the surgical fasteners positioned further from the centerline such that the distance defined between the penetrating tips of the surgical fasteners and the corresponding pockets formed in the tissue contacting surface of the anvil member varies with the distance between the surgical fasteners and the centerline of the cartridge member. For example, it is envisioned that the distance defined between the penetrating tips of the surgical fasteners and the corresponding pockets formed in the tissue contacting surface of the anvil member may increase with the distance between the surgical fasteners and the centerline of the cartridge member. 
     In one embodiment of the surgical fastener applying apparatus, the plurality of surgical fasteners includes a plurality of first surgical fasteners that are arranged into first rows, second rows, and third rows. In this embodiment, the first rows are positioned nearer to a centerline of the cartridge member, the second rows are positioned outwardly of the first rows and further from the centerline, and the third rows are positioned outwardly of the second rows and furthest from the centerline. 
     In another aspect of the present disclosure, a surgical fastener applying apparatus is disclosed that includes an anvil member, a cartridge member extending along a longitudinal axis that is movably coupled to the anvil member and configured and dimensioned to retain a plurality of surgical fasteners therein, and one or more pushers that are movably positioned within the cartridge member to eject the plurality of surgical fasteners from the cartridge member into the anvil member to effectuate formation of the plurality of surgical fasteners such that at least two different compressive forces are applied to tissue. 
     The at least one pusher includes a base portion and a plurality of pusher plates that are connected to the base portion such that the plurality of pusher plates are repositionable relative to a centerline of the cartridge member during movement of the at least one pusher. In one embodiment, it is envisioned that the pusher plates may extend from the base portion such that adjacent pusher plates define an acute angle therebetween. Additionally, or alternatively, it is envisioned that the pusher(s) may be of unitary construction, and/or that each pusher plate may extend from the base portion to define a different length. 
     Additionally, it is envisioned that the pusher(s) and the surgical fasteners may be configured and dimensioned such that the compressive forces applied to the tissue are varied along an axis that is transverse to the longitudinal axis of the cartridge member. 
     These and other features of the surgical access apparatus disclosed herein will become more readily apparent to those skilled in the art through reference to the detailed description of various embodiments of the present disclosure that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein: 
         FIG. 1  is a top, perspective view of a surgical fastener applying apparatus having a tool assembly at a distal end thereof for applying a plurality of surgical fasteners to tissue, according to one embodiment of the present disclosure; 
         FIG. 2  is a side, perspective view of an exemplary surgical fastener; 
         FIG. 3  is a partial, perspective view of the tool assembly seen in  FIG. 1 , with parts separated, illustrating an anvil and a surgical fastener cartridge assembly including a surgical fastener cartridge incorporating angled pushers; 
         FIG. 4  is a schematic, enlarged view of the area of detail indicated in  FIG. 3  illustrating a tissue contacting surface of the anvil and a plurality of fastener pockets formed therein; 
         FIG. 5  is a longitudinal, cross-sectional view taken along line  5 - 5  in  FIG. 4  illustrating the fastener pockets formed in the tissue contacting surface of the anvil; 
         FIG. 5A  is a lateral, cross-sectional view of an alternative embodiment of the tool assembly seen in  FIG. 1  taken through the fastener pockets formed in the anvil and retention slots formed in the surgical fastener cartridge; 
         FIG. 6  is a lateral, cross-sectional view of the tool assembly seen in  FIG. 1  taken through the fastener pockets formed in the anvil and retention slots formed in the surgical fastener cartridge; 
         FIG. 7  is a side, perspective view of the surgical fastener shown in  FIG. 2  exhibiting a standard “B” shaped configuration subsequent to formation through engagement with the fastener pockets formed in the anvil seen in  FIG. 3 ; 
         FIG. 8  is side, perspective view of a surgical fastener having a single-loop configuration subsequent to formation through contact with the fastener pockets formed in the tissue contacting surface included in an alternative embodiment of the anvil seen in  FIG. 3 ; 
         FIG. 9A  is a side, plan view of one embodiment of the surgical fastener shown in  FIG. 2  including legs having a first length and shown prior to formation; 
         FIG. 9B  is a cross-sectional view of the surgical fastener shown in  FIG. 9A  subsequent to formation within adjacent tissue segments to apply a first compressive force thereto; 
         FIG. 10A  is a side view of another embodiment of the surgical fastener shown in  FIG. 2  including legs having a second, shorter length and shown prior to formation; 
         FIG. 10B  is a cross-sectional view of the surgical fastener shown in  FIG. 10A  subsequent to formation within adjacent tissue segments to apply a second, greater compressive force thereto; 
         FIG. 11A  is a side view of still another embodiment of the surgical fastener shown in  FIG. 2  including legs having a third, shorter length and shown prior to formation; 
         FIG. 11B  is a cross-sectional view of the surgical fastener shown in  FIG. 11A  subsequent to formation within adjacent tissue segments to apply a third, greater compressive force thereto; 
         FIG. 12  is a partial, longitudinal, perspective view, with parts removed, of the surgical fastener cartridge seen in  FIG. 3  illustrating the plurality of surgical fasteners arranged into inner, intermediate, and outer rows; 
         FIG. 13  illustrates an end-to-end anastomosis device for use with alternative embodiments of the anvil and the surgical fastener cartridge seen in  FIG. 3 ; 
         FIG. 14  illustrates a surgical fastener applying instrument for use with alternative embodiments of the anvil and the surgical fastener cartridge seen in  FIG. 3 ; 
         FIG. 15  illustrates a transverse anastomosis fastener applying instrument for use with alternative embodiments of the anvil and the surgical fastener cartridge seen in  FIG. 3 ; 
         FIG. 16  is a lateral, cross-sectional view of an alternative embodiment of the tool assembly seen in  FIG. 1  taken through the fastener pockets formed in the anvil and retention slots formed in the surgical fastener cartridge in accordance with yet another embodiment of the present disclosure; 
         FIG. 17  is perspective view of a plurality of anvil plates, with parts separated, in accordance with still another embodiment of the present disclosure; and 
         FIG. 18  is a perspective view of the plurality of anvil plates seen in  FIG. 17  after assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Various embodiments of the presently disclosed surgical fastener applying apparatus, and methods of using the same, will now be described in detail with reference to the drawings wherein like references characters identify similar or identical elements. In the drawings, and in the description which follows, the term “proximal” will refer to the end the surgical fastener applying apparatus, or component thereof, that is closest to the clinician during use, while the term “distal” will refer to the end that is furthest from the clinician, as is traditional and conventional in the art. In addition, the term “surgical fastener” should be understood to include any substantially rigid structure that is suitable for the intended purpose of joining tissue together, including but not being limited to surgical staples, clips, and the like. 
       FIG. 1  illustrates a surgical fastener applying apparatus  1000 , of either the re-usable or disposable variety, including a handle assembly  1002 , with a movable handle  1003   A  and a stationary handle  1003   B , that is operatively connected to a tool assembly  1004  through a distally extending elongated shaft  1006 . In various embodiments, the handle assembly  1002  may be manually operated, and either additionally or alternatively, may include motorized, hydraulic, ratcheting, or other such mechanisms. In general, the tool assembly  1004  is adapted to clamp, fasten together, and sever adjacent tissue segments along a cut-line. 
     Referring now to  FIGS. 2-6  as well, the tool assembly  1004  includes a first jaw  1008  that is pivotally coupled to a second jaw  1010  to facilitate approximation thereof. The first jaw  1008  of the tool assembly  1004  includes an anvil  1100 , and the second jaw  1010  includes a surgical fastener cartridge assembly  1200  that is loaded with a plurality of surgical fasteners  100  ( FIGS. 2, 3 ). Pivoting the movable handle  1003   A  towards the stationary handle  1003   B  ( FIG. 1 ) approximates the first jaw  1008  and the second jaw  1010 . After the jaws  1008 ,  1010  are in close operative alignment, continued pivoting of the movable handle  1003   A  ejects the plurality of surgical fasteners  100  ( FIG. 3 ) from the surgical fastener cartridge assembly  1200  such that the surgical fasteners  100  are driven into the anvil  1100 , thus being formed into completed surgical fasteners, as described in further detail below. The tool assembly  1004  and/or the surgical fastener cartridge assembly  1200  may comprise a removable and replaceable loading unit for the surgical fastener applying apparatus  1000 . 
     As best seen in  FIG. 2 , each surgical fastener  100  includes two legs  102  that are connected by a backspan  104  extending therebetween. The legs  102  extend from the backspan  104  to penetrating ends  106  to define a length “L” prior to formation. The dimensions of the backspan  106  and the legs  102  can be varied such that the surgical fasteners  100  may be used to fasten tissue having varying attributes, e.g., to fasten tissue of varying thickness, and/or to accommodate the presence of scar tissue. The dimensions of the legs  102  and the backspan  104  can be varied such that the surgical fasteners  100  can apply varying amounts of pressure to tissue. 
     The legs  102  and the backspan  104  may define a cross-section having any suitable geometric configuration including, but not limited to, rectangular, oval, square, triangular, trapezoidal, etc. The legs  102  and the backspan  104  may exhibit the same geometrical configuration, as shown in  FIG. 2 , or alternatively, the legs  102  and the backspan  104  may exhibit different geometrical configurations. For example, the legs  102  may exhibit a rectangular cross-section, whereas the backspan  104  may exhibit an oval cross-section. 
     The penetrating ends  106  of the legs  102  may be tapered to facilitate the penetration of tissue, or alternatively, the penetrating ends  106  may not include a taper. In various embodiments, it is also envisioned that the penetrating ends  108 ,  110  may define either a conical surface, or a flat surface. 
     Prior to formation, the legs  102  of each surgical fastener  100  may extend from the backspan  104  such that they are substantially parallel. In the alternative, the legs  102  may converge or diverge from the backspan  104 . 
     Referring now to  FIG. 3  in particular, the surgical fastener applying apparatus  1000  also includes a knife member  1007  that is operatively connected to a drive beam  1012 , as described in commonly assigned U.S. Pat. No. 7,398,908, currently assigned to Tyco Healthcare Group LP, the contents of which are hereby incorporated by reference herein in its entirety, and discussed in further detail below. The knife member  1007  may be configured and dimensioned for simultaneous engagement with both the anvil member  1100  and a cavity  1222  that is defined by the second jaw  1010 . 
     During use, the tool assembly  1004  is first actuated to clamp onto tissue by manipulating the movable handle  1003   A  to advance a control rod (not shown) distally. Distal advancement of the control rod results in corresponding movement of the knife member  1007 , and effectuates approximation of the anvil member  1100  and the surgical fastener cartridge assembly  1200 . With tissue clamped between the anvil member  1100  and the surgical fastener cartridge assembly  1200 , the fasteners  100  ( FIGS. 2, 3 ) are fired from the surgical fastener applying apparatus  1000  ( FIG. 1 ) into the tissue. The movable handle  1003   A  is then operated again to further advance the knife member  1007 . 
     Referring now to  FIGS. 3-6 , the anvil  1100  and the surgical fastener cartridge assembly  1200  of the tool assembly  1004  ( FIG. 1 ) will be discussed in further detail. The anvil  1100  is an elongated member having a tissue contacting surface  1102  with a plurality of pockets  1104  ( FIG. 4 ) formed therein. Each of the pockets  1104  is positioned to receive the legs  102  ( FIG. 2 ) of the surgical fastener  100 , and is configured to redirect the legs  102  to thereby form the surgical fasteners  100 . More particularly, in the embodiment of the anvil  1100  seen in  FIGS. 3-6 , each pocket  1104  includes two forming surfaces  1106 ,  1108  ( FIGS. 4, 5 ) that extend into the anvil  1100 , i.e., away from the tissue contacting surface  1102 , to define a depth ‘D” ( FIG. 5 ). Upon engagement of the legs  102  ( FIG. 2 ) with the forming surfaces  1106 ,  1108 , the forming surfaces  1106 ,  1108  guide the legs  102  inwardly in the direction of arrows “A” ( FIG. 4 ) to facilitate deformation of the surgical faster  100  into the standard “B” shaped configuration ( FIG. 7 ). In an alternative embodiment, the anvil  1100  may include pockets  1104  that are configured and dimensioned to deform the surgical fastener  100  such that the surgical fastener  100  defines a single-loop configuration ( FIG. 8 ) upon formation. It is also envisioned that the surgical fastener  100  may exhibit other configurations upon formation. 
     The pockets  1104  are arranged into rows disposed on opposite sides of a slot  1110  extending at least partially through the anvil member  1100  ( FIGS. 3, 4 ). The slot  1110  is configured to accommodate longitudinal movement of the knife member  1007  ( FIG. 3 ) such that tissue may be severed along a cut-line. Although the slot  1110  is depicted as extending longitudinally through the anvil  1100 , in alternative embodiments, the slot  1110  may define a configuration that is angled, arcuate, or shaped otherwise. The slot  1110  may extend along a centerline of the anvil  1100 , as shown in the embodiment illustrated in  FIGS. 3 and 4 , or alternatively, the slot  1110  may be spaced therefrom. 
     In the specific embodiment of the anvil  1100  seen in  FIGS. 3-6 , the pockets  1104  are arranged into a pair of outer rows  1112   A  ( FIG. 4 ) that are spaced laterally outward of the slot  1110  and furthest therefrom, a pair of intermediate rows  1112   B  that are spaced laterally inward of the pair of outer rows  1112   A , and a pair of inner rows  1112   C  that are spaced laterally inward of the pair of intermediate rows  1112   B  and closest to the slot  1110 . While the anvil  1100  is depicted as including three rows of pockets  1104 , i.e., the respective outer, intermediate, and inner rows  1112   A ,  1112   B ,  1112   C , the arrangement of pockets  1104  into fewer or greater numbers of rows in alternative embodiments is also within the scope of the present disclosure. With reference to  FIG. 5A , in one particular embodiment, the anvil  1100  includes additional rows of pockets  1104  to accommodate for any lateral deflection experienced by the surgical fasteners  100 , i.e., towards or away from the slot  1110 , as they are deployed through the tissue grasped between the jaws  1008 ,  1010  ( FIG. 1 ) of the tool assembly  1004 . The surgical fasteners  100  may be deflected laterally, for example, due to the presence of scar tissue, irregularities in the tissue, or tissue of increased thickness. By providing additional rows of pockets  1104 , the likelihood of engagement between the surgical fasteners  100  and one of the pockets  1104 , and thus, proper fastener formation, is increased. 
     With continued reference to  FIGS. 3-6 , the surgical fastener cartridge assembly  1200  will be discussed. In the particular embodiment seen in  FIGS. 3 and 6 , the surgical fastener cartridge assembly  1200  is loaded with three varieties of surgical fastener, i.e., the surgical fasteners  100   A ,  100   B ,  100   C  seen in  FIGS. 9A-11B . In alternative embodiments, however, the surgical fastener cartridge assembly  1200  may include fewer or additional varieties of surgical fasteners  100 . 
     Turning momentarily to  FIGS. 9A-11B , it can be seen that the surgical fasteners  100   A ,  100   B ,  100   C  are substantially identical but for the respective lengths “L A ,” “L B ,” “L C ” defined by their legs  102   A ,  102   B ,  102   C . Specifically, the length “L B ” defined by the legs  102   B  of the surgical fasteners  100   B  is less than the length “L A ” defined by the legs  102   A  of the surgical fasteners  100   A , and the length “L C ” defined by the legs  102   C  of the surgical fasteners  100   C  is less than the length “L B ” defined by the legs  102   B  of the surgical fasteners  100   B . Stated differently, the surgical fasteners  100   C  have the shortest legs  102   C , and the surgical fasteners  100   A  have the longest legs  102   A . 
     As seen in  FIGS. 3 and 6 , the surgical fastener cartridge assembly  1200  includes a surgical fastener cartridge body  1202  extending along an axis “X-X” ( FIG. 3 ) that houses, among other components, the surgical fasteners  100   A ,  100   B ,  100   C  ( FIGS. 9A-11B ). A longitudinal slot  1204  extends through the surgical fastener cartridge body  1202  that is configured and dimensioned to accommodate longitudinal movement of the knife  1007  ( FIG. 3 ) such that tissue may be severed along the aforementioned cut-line. Although the slot  1204  is depicted as extending longitudinally through the surgical fastener cartridge body  1202 , in alternative embodiments, the slot  1204  may define a configuration that is angled, arcuate, or shaped otherwise. The slot  1204  may extend along a centerline of the surgical fastener cartridge body  1202 , as shown in the embodiment illustrated in  FIGS. 3 and 6 , or alternatively, the slot  1204  may be spaced therefrom. 
     The surgical fastener cartridge body  1202  is defined by a substantially planar bottom wall  1206 , a pair of side walls  1208 ,  1210  that extend upwardly therefrom, and a top wall  1212 . The top wall  1212  is also substantially planar, and extends in substantially parallel relation to the bottom wall  1206 . The top wall  1212  includes a tissue engaging surface  1214 , e.g., for maintaining the position of the tissue to be cut. When the jaws  1008 ,  1010  ( FIG. 1 ) of the tool assembly  1004  are in an approximated position, the tissue engaging surface  1214  of the top wall  1212  is spaced a distance “Y” ( FIG. 6 ) from the tissue contacting surface  1102  of the anvil  1100 . 
     The tissue engaging surface  1214  of the top wall  1212  further includes a plurality of fastener retention slots  1216  formed therein. Each fastener retention slot  1216  is configured and dimensioned to receive one of the surgical fasteners  100   A ,  100   B ,  100   C  ( FIGS. 6, 9A-11B ). To drive the surgical fasteners  100   A ,  100   B ,  100   C  upwardly, i.e., towards the top wall  1212 , and through the fastener retention slots  1216 , the surgical fastener cartridge assembly  1200  further includes a plurality of pushers  1218  ( FIG. 3 ) and a sled  1220  that is disposed within the cavity  1222  defined by the second jaw  1010  of the tool assembly  1004  ( FIG. 1 ). 
     The pushers  1218  are positioned beneath the surgical fasteners  100   A ,  100   B ,  100   C , and are configured to engage the sled  1220  as the sled  1220  traverses the cavity  1222  via translation of the drive beam  1012 , or other such actuation component. Each pusher  1218  includes a plurality of pusher plates, identified generally by the reference character  1224 , corresponding in number to the number of rows of fastener lines desired within the tissue upon firing of the surgical fastener applying apparatus  1000  ( FIG. 1 ). Accordingly, in the embodiment seen in  FIGS. 3 and 5 , each pusher  1218  includes three pusher plates, i.e., outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C , respectively. In alternative embodiments, however, it is envisioned that the pushers  1218  may include fewer or greater numbers of pusher plates  1224  should the desired number of rows of fastener lines be fewer or greater. 
     Each of the respective outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C  extends upwardly from, and is connected to, a base portion  1226  of the pusher  1218  at one or more hinge members  1228 . In one embodiment, as seen in  FIG. 6  for example, the hinge member(s)  1228  may comprise a living hinge formed integrally with the pusher  1218 . The hinge member(s)  1228  permit the outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C  to diverge as the pushers  1218  are driven upwardly by the sled  1220  ( FIG. 3 ). The outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C  extend from the base portion  1226  in offset relation such that the outer pusher plate  1224   A  and the intermediate pusher plate  1224   B  subtend a first acute angle θ 1 , while the intermediate pusher plate  1224   B  and the outer pusher plate  1224   C  subtend a second acute angle θ 2 . 
     In one particular embodiment, the pushers  1218  are unitary in construction, as shown in  FIG. 6  for example, such that the pusher plates  1224  extend directly from the base portion  1226 . For example, it is envisioned that the pusher plates  1224  may be integrally, e.g., monolithically, formed with the base portion  1226 . It is also envisioned, however, that the pushers  1218  and the pusher plates  1224  may constitute separate, discrete structures. 
     The outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C  are configured and dimensioned to engage the surgical fasteners  100   A ,  100   B ,  100   C , respectively. Consequently, the surgical fasteners  100   A ,  100   B ,  100   C  are also arranged within the surgical fastener cartridge body  1202  in offset relation such that the surgical fasteners  100   A ,  100   B  subtend the first acute angle θ 1  and the surgical fasteners  100   B ,  100   C  subtend the second acute angle θ 2 . 
     The distance “D” measured from the pushers  1218  to the tissue contacting surface  1102  of the anvil  1100  for each of the pushers  1218  is substantially the same. While the height of each pusher  1218 , measured along the vertical axis “Z-Z,” or height, of the surgical fastener cartridge  1200  is substantially the same, the offset relationship between the respective outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C  results in each pusher plate defining a different length. More specifically, in the embodiment seen in  FIG. 6 , the outer pusher plate  1224   A  defines a greater length than the intermediate pusher plate  1224   B , and the intermediate pusher plate  1224   B  defines a greater length than the inner pusher plate  1224   C . Stated differently, the pushers  1218  are arranged beneath the surgical fasteners  100   A ,  100   B ,  100   C  such that shortest pusher plate, i.e., inner pusher plate  1224   C , is disposed closest to the slot  1204  and beneath the shortest surgical fastener, i.e., the surgical fastener  100   A , and the longest pusher plate, i.e., the outer pusher plate  1224   A , is disposed furthest from the slot  1204  and beneath the longest surgical fastener, i.e., the surgical fasteners  100   C . 
     The offset relationship between the respective outer, intermediate, and inner pusher plates  1224   A ,  1224   B ,  1224   C , and the corresponding offset relationship between the surgical fasteners  100   A ,  100   B ,  100   C , results in the definition of a variable distance between the respective penetrating ends  106   A ,  106   B ,  106   C  of the surgical fasteners  100   A ,  100   B ,  100   C  and the pockets  1104  formed in the tissue contacting surface  1102  of the anvil  1100 . More specifically, the penetrating ends  106   A  of the surgical fasteners  100   A  are spaced a distance “X A ” from the pockets  1104  comprising the pair of outer rows  1112   A  ( FIG. 4 ), the penetrating ends  106   B  of the surgical fasteners  100   B  are spaced a distance “X B ” from the pockets  1104  comprising the intermediate pair of rows  1112   B , and the penetrating ends  106   C  of the surgical fasteners  100   C  are spaced a distance “X C ” from the pockets  1104  comprising the inner pair of rows  1112   C . In the illustrated embodiment, the distance ‘X A ” is less than the distance “X B ,” and the distance “X B ” is less than the distance “X C .” 
     The fastener retention slots  1216  are arranged into pairs of outer, intermediate, and inner rows  1230   A ,  1230   B ,  1230   C  ( FIG. 3 ) that correspond respectively to the pairs of outer, intermediate, and inner rows  1112   A ,  1112   B ,  1112   C  ( FIG. 4 ) of pockets  1104  formed in the tissue contacting surface  1102  of the anvil  1100 , thus increasing the likelihood of proper engagement between the surgical fasteners  100   A ,  100   B ,  100   C  and the pockets  1104 . Accordingly, upon ejection of the surgical fasteners  100   A ,  100   B ,  100   C  from the fastener retention slots  1216 , the surgical fasteners  100   A  are directed into contact with the pockets  1104  comprising the pair of outer rows  1112   A , the surgical fasteners  100   B  are directed into contact with the pockets  1104  comprising the pair of intermediate rows  1112   B , and the surgical fasteners  100   C  are directed into contact with the pockets  1104  comprising the pair inner of rows  1112   C . In one embodiment, as seen in  FIG. 6 , the fastener retention slots  1216  comprising the pairs of outer, intermediate, and inner rows  1230   A ,  1230   B ,  1230   C  may be connected at lead-ins  1232 , which may be radiused, as shown, or of any other suitable configuration, e.g., planar or pointed. Alternatively, however, it is envisioned that the fastener retention slots  1216  comprising the respective outer, intermediate, and inner pairs of rows  1230   A ,  1230   B ,  1230   C  may be discrete. 
     The pair of outer rows  1230   A  ( FIGS. 3, 6 ) of fastener retention slots  1216  are spaced laterally outward of the slot  1204  and are disposed furthest therefrom, the pair of intermediate rows  1230   B  are spaced inwardly of the pair of outer rows  1230   A , and the pair of inner rows  1230   C  are spaced inwardly of the pair of intermediate rows  1230   B  and are disposed closest to the slot  1204 , each of the respective inner, intermediate, and outer pairs of rows  1230   A ,  1230   B ,  1230   C  being arranged on opposite sides of the slot  1204 . Consequently, as the surgical fasteners  100   A ,  100   B ,  100   C  exit the fastener retention slots  1216  and are formed within tissue, the surgical fasteners  100   A ,  100   B ,  100   C  will be arranged to respectively define outer, intermediate, and inner fastener lines on opposite sides of the cut-line formed in the tissue. While the surgical fastener cartridge body  1202  is depicted as including three pairs of rows, i.e., the respective outer, intermediate, and inner rows  1230   A ,  1230   B ,  1230   C , fewer and greater numbers of rows of fastener retention slots  1216  may be included in alternative embodiments of the surgical fastener cartridge assembly  1200 . 
     With reference again to  FIGS. 9A-9B , the surgical fasteners  100   A  will be discussed before and after formation. As seen in  FIG. 9A , before formation, the legs  102   A  of the surgical fastener  100   A  define a length “L A ” that is measured from the penetrating ends  106   A  to an outer surface  108   A  of the backspan  104   A . After formation, the legs  102   A  are configured such that the surgical fastener  100   A  defines, for example, the standard “B” shaped configuration ( FIG. 9B ). When formed within adjacent tissue segments “T 1 ,” “T 2 ,” the tissue segments “T 1 ,” “T 2 ” are compressed and maintained in approximation between an inner surface  110   A  of the curved legs  102   A  and an inner surface  112   A  of the backspan  104   A  within a compressive space  114   A . The compression of the tissue segments “T 1 ,” “T 2 ” creates a biasing force “B A ” in the tissue segments “T 1 ,” “T 2 ” that endeavors to force the legs  102   A  of the surgical fastener  100   A  outwardly in the direction indicated by arrows  1 . The legs  102   A  resist yielding, but their length “L A ” allows the legs  102   A  to be deflected outwardly, albeit a minimal distance, under the influence of the biasing force “B A ” such that the compressive space  114   A  ultimately defines a dimension “C A .” Maintaining the tissue segments “T 1 ,” “T 2 ” within the compressive space  114   A  subjects the tissue segments “T 1 ,” “T 2 ” to a corresponding compressive force “F A ” which limits, but does not completely restrict, the flow of blood through the tissue surrounding the surgical fastener  100   A . Thus, unnecessary necrosing of the fastened tissue segments “T 1 ,” “T 2 ” may be prevented or impeded. 
     With reference now to  FIGS. 10A-10B , the surgical fastener  100   B  is shown before and after formation, respectively. Before formation, the legs  102   B  define a length “L B ” that is measured from the penetrating ends  106   B  to the outer surface  108   B  of the backspan  104   B . The length “L B ” is less than the length “L A ” defined by the legs  102   A  of the surgical fastener  100   A  illustrated in  FIGS. 9A-9B . After formation, the legs  102   B  are configured such that the surgical fastener  100   B  also defines the standard “B” shaped configuration ( FIG. 10B ). When the surgical fastener  100   B  is formed within tissue segments “T 1 ,” “T 2 ,” the compressed tissue segments “T 1 ,” “T 2 ” exert a biasing force “B B ” that endeavors to force the legs  102   B  outwardly in the direction indicated by arrows  1 . The shorter length “L B ” of the legs  102   B  allows the legs  102   B  to resist yielding to a greater extent than the legs  102   A  of the surgical fastener  100   A  such that a compressive space  114   B  is ultimately defined with a dimension “C B ” that is smaller in comparison to the dimension “C A ” of the compressive space  114   A  illustrated in  FIG. 9B . The smaller dimension “C B ” of the compressive space  114   B  results in the application of a corresponding compressive force “F B ” to the tissue segments “T 1 ,” “T 2 ” that is greater than the compressive force “F A ” applied by the surgical fastener  100   A . Consequently, the flow of blood through the tissue surrounding the surgical fastener  100   B  is further restricted when compared to the flow of blood through the tissue surrounding the surgical fastener  100   A , thereby further facilitating hemostasis. The compressive force “F B ” does not completely restrict the flow of blood through the tissue surrounding the surgical fastener  100   B , however. Thus, unnecessary necrosing of the fastened tissue segments “T 1 ,” “T 2 ” may be prevented or impeded. 
       FIGS. 11A-11B  illustrate the surgical fastener  100   C  before and after formation, respectively. Before formation, the legs  102   C  define a length “L C ” that is measured from the penetrating ends  106   C  to the outer surface  108   C  of the backspan  104   C . The length “L C ” is less than the length “L B ” defined by the legs  102   B  of the surgical fastener  100   B  illustrated in  FIGS. 10A-10B . After formation, the legs  102   C  are configured such that the surgical fastener  100   C  also defines the standard “B” shaped configuration ( FIG. 11B ). When the surgical fastener  100   C  is formed within tissue segments “T 1 ,” “T 2 ,” the compressed tissue segments “T 1 ,” “T 2 ” exert a biasing force “B C ” that endeavors to force the legs  102   C  outwardly in the direction indicated by arrows  1 . The shorter length “L C ” of the legs  102   C  allows the legs  102   C  to resist yielding to a greater extent than the legs the legs  102   B  of the surgical fastener  100   B  such that a compressive space  114   C  is ultimately defined with a dimension “C C ” that is smaller in comparison to the dimension “C B ” of the compressive space  114   B  illustrated in  FIG. 10B . The smaller dimension “C C ” of the compressive space  114   C  results in the application of a corresponding compressive force “F C ” to the tissue segments “T 1 ,” “T 2 ” that is greater than the compressive force “F B ” applied by the surgical fastener  100   B . Consequently, the flow of blood through the tissue surrounding the surgical fastener  100   C  is further restricted when compared to the flow of blood through the tissue surrounding the surgical fastener  100   B . The compressive force “F B ” applied to the tissue segments “T 1 ,” “T 2 ” substantially, if not completely restricts the flow of blood through the tissue surrounding the surgical fastener  100   C , thereby further facilitating, and effectuating hemostasis. 
     The length “L A ” of the legs  102   A , the length “L B ” of the legs  102   B , and the length “L C ” of the legs  102   C , as well as the corresponding dimensions “C A ,” “C B ,” “C C ” of the compressive spaces  114   A ,  114   B ,  114   C  occupied by tissue segments “T 1 ,” “T 2 ” when the respective surgical fasteners  100   A ,  100   B ,  100   C  are in their formed conditions, may be altered or varied in different embodiments of the present disclosure to effectuate any desired level of hemostasis and blood flow in the tissue segments “T 1 ,” “T 2 .” Furthermore, the size of the surgical fasteners  100   A ,  100   B ,  100   C  may be substantially the same, or may vary within a row of retention slots  1216 , or in any other pattern. 
     Referring now to  FIGS. 6 and 12 , the pushers  1218  are arranged longitudinally on opposite sides of the slot  1204  extending through the surgical fastener cartridge body  1202  such that the surgical fasteners  100   A ,  100   B ,  100   C  define pairs of outer, intermediate, and inner rows  1234   A ,  1234   B ,  1234   C  that correspond respectively in position to the outer, intermediate, and inner rows  1230   A ,  1230   B ,  1230   C  ( FIG. 3 ) of fastener retention slots  1216 . Accordingly, the surgical fasteners  100   A  comprising the pair of outer rows  1234   A  will be spaced laterally outward, and furthest from, the cut-line formed upon fastening, the surgical fasteners  100   B  comprising the pair of intermediate rows  1234   B  will be disposed inwardly of the surgical fasteners  100   A  comprising the pair of outer rows  1234   A , and the fasteners  100   C  comprising the pair of inner rows  1234   C  will be disposed inwardly of the surgical fasteners  100   B  comprising the pair of intermediate rows  1234   B , along the cut-line, and closest thereto. The respective outer, intermediate, and inner rows  1234   A ,  1234   B ,  1234   C  of surgical fasteners  100   A ,  100   B ,  100   C  will be applied to the tissue such that they define corresponding lines of fasteners on opposite sides of the cut-line. 
     The surgical fastener cartridge body  1202  seen in  FIGS. 3, 6, and 12  is illustrated as including outer, intermediate, and inner rows  1234   A ,  1234   B ,  1234   C  exclusively including the respective surgical fasteners  100   A ,  100   B ,  100   C . In other words, each surgical fastener disposed in a particular row will have the same configuration, i.e., legs of the same length. By arranging the surgical fasteners  100   A ,  100   B ,  100   C  in this manner, the surgical fasteners with the shortest leg length resulting in the greatest compressive force, i.e., surgical fasteners  100   C , are deployed closest to the cut-line, and the surgical fasteners having longer legs and resulting in lesser compressive forces, i.e., surgical fasteners  100   A  and  100   B , are provided further from the cut-line. Consequently, arranging the surgical fasteners  100   A ,  100   B ,  100   C  in this way minimizes the flow of blood through the tissue immediately adjacent the cut-line and gradually increases the flow of blood through the tissue spaced a greater lateral distance therefrom. It should be appreciated that the length of the legs could be varied to accommodate tissue of different thicknesses and to control tissue compression by the fasteners  100   A ,  100   B ,  100   C . 
     In alternative embodiments of the present disclosure, it is envisioned that the surgical fastener cartridge body  1202  may include outer, intermediate, and inner rows  1234   A ,  1234   B ,  1234   C  comprising a combination of surgical fasteners  100   A ,  100   B ,  100   C  such that a particular row may include a variety of surgical fasteners having different configurations, e.g., legs of different lengths. By providing a variety of surgical fasteners in each row, the flow of blood through the tissue can be controlled longitudinally, along the cut-line, as well laterally as the distance therefrom is varied. 
     With continued reference to  FIG. 12 , by loading the surgical fastener cartridge  1200  ( FIG. 3 ) with a variety of surgical fasteners, e.g., surgical fasteners  100   A ,  100   B ,  100   C , and by arranging the surgical fasteners  100   A ,  100   B ,  100   C  such that those with the shortest legs, i.e., surgical fasteners  100   C , are closest to the cut-line and those with the longest legs, i.e., surgical fasteners  100   A , are furthest from the cut-line, a greater range of tissue thickness can be effectively fastened, as the thickness of the tissue will generally increase with the distance from the cut-line, e.g., as a result of clamping by the tool assembly  1004  ( FIG. 1 ). Accordingly, loading the surgical fastener cartridge  1200  with a variety of surgical fasteners having legs of various lengths allows a single surgical fastener cartridge  1200  to fasten tissue of varying thickness. 
     Referring now to  FIGS. 1-6 and 9-12 , a method of fastening tissue with the surgical fastener applying apparatus  1000  ( FIG. 1 ) will be discussed. During use, the surgical fastener applying apparatus  1000  is approximated and fired similarly to, and in accordance with other known surgical fastener applying apparatus, such as that disclosed in commonly assigned U.S. Pat. No. 5,865,361, currently assigned to Tyco Healthcare Group LP, the contents of which are hereby incorporated by reference herein in its entirety. 
     The movable handle  1003   A  is operatively connected to an actuation shaft, which receives the proximal end of a control rod, such that manipulation of the movable handle  1003   A  results in linear advancement of the actuation shaft, which causes corresponding linear advancement of the control rod. An axial drive assembly is also provided that is engagable with the control rod. More specifically, the axial drive assembly includes the elongated drive beam  1012  ( FIG. 3 ), which includes a distal end that supports the knife blade  1007 , and a drive member that is configured and dimensioned for engagement with the control rod. As seen in  FIG. 3 , the knife  1007  is positioned to translate behind the sled  1220 . 
     After the surgical fastener applying apparatus  1000  ( FIG. 1 ) is manipulated to position the target tissue between the open jaws  1008 ,  1010  ( FIG. 1 ) of the tool assembly  1004 , the jaws  1008 ,  1010  are approximated using the handle assembly  1002  to clamp the target tissue therebetween and apply a compressive force thereto. Specifically, manipulation of the movable handle  1003   A  advances the actuation shaft to effectuate corresponding advancement of the control rod. Since the control rod is connected at its distal end to the drive assembly, which includes the aforementioned drive beam  1113 , distal movement of the control rod causes corresponding movement of the drive beam  1113 , which in turn, forces the anvil  1100  towards the surgical fastener cartridge assembly  1200 . 
     With the tissue securely clamped between the jaws  1008 ,  1010  ( FIG. 1 ), the surgical fastener applying apparatus  1000  is then fired to eject the surgical fasteners, e.g., the surgical fasteners  100   A ,  100   B ,  100   C  ( FIGS. 9A-11B ). To fire the surgical fastener applying apparatus  1000 , the movable handle  1003   A  is again manipulated to cause advancement of the drive assembly, which causes the sled  1220  ( FIG. 3 ) to traverse the cartridge body  1202 , and eject the plurality of surgical fasteners  100  from the surgical fastener cartridge assembly  1200 . More specifically, as the sled  1220  moves distally, it engages the pushers  1218  ( FIGS. 3, 6 ) to thereby drive the surgical fasteners  100   A ,  100   B ,  100   C  upwardly, i.e., towards the top wall  1212  of the surgical fastener cartridge body  1202 . As the surgical fasteners  100   A ,  100   B ,  100   C  are driven upwardly, the fastener retention slots  1216  ( FIGS. 3, 6 ) maintain the relative positions thereof. 
     After passing through the fastener retention slots  1216 , the surgical fasteners  100   A ,  100   B ,  100   C  pass through the tissue and are forced into engagement with the pockets  1104  formed in the tissue contacting surface  1102  of the anvil  1100 , thereby achieving, for example, the formed configurations seen in  FIGS. 9B, 10B, and 11B , respectively. Upon formation within the tissue, the surgical fasteners  100   A ,  100   B ,  100   C  limit the blood flow through the tissue immediately adjacent and surrounding the cut-line to thereby effectuate hemostasis, while permitting greater blood flow through the tissue spaced laterally therefrom to minimizing necrosing of the tissue, as discussed above. 
     While the tool assembly  1004  ( FIG. 1 ) has been discussed in connection with the surgical fastener applying apparatus  1000 , which is adapted for use in laparoscopic procedures for performing surgical anastomotic fastening of tissue, the tool assembly  1004  may be adapted for use with any surgical instrument suitable for the intended purpose of applying the plurality of surgical fasteners, e.g., the surgical fasteners  100  ( FIG. 2 ), the surgical fasteners  100   A  ( FIGS. 9A, 9B ), the surgical fasteners  100   B  ( FIGS. 10A, 10B ), and/or the surgical fasteners  100   C  ( FIGS. 11A, 11B ), to a section of tissue, and thereafter, severing the tissue along a cut-line. 
     For example, the tool assembly  1004  ( FIG. 1 ) may be adapted for use with an end-to-end anastomosis (EEA) apparatus  2000  ( FIG. 10 ), such as that disclosed in commonly assigned U.S. Pat. No. 7,455,676, currently assigned to Tyco Healthcare Group LP, the contents of which are hereby incorporated by reference herein in its entirety. The EEA apparatus  2000  includes a handle assembly  2002  having at least one pivotable actuating handle member  2004 , and advancing means  2006 . Extending from handle assembly  2002 , there is provided a tubular body portion  2008  that terminates in a fastener ejection (tool) assembly  2010  having a circular fastener cartridge  2012  that is configured and dimensioned to retain a plurality of surgical fasteners therein. An anvil shaft  2014  operatively couples an anvil assembly  2016  to the handle assembly  2002  such that the anvil assembly  2016  is repositionable from a location where it is in close cooperative alignment with the fastener cartridge  2012  to a location where it is spaced apart from the fastener staple cartridge  2012 . 
     The tool assembly  2010  includes a fastener ejection member that is positioned within the fastener cartridge  2012 . The fastener ejection member includes a distal portion defining concentric rings of peripherally spaced staple pushers that are received within a respective staple retention slot to eject the surgical fasteners from the fastener cartridge  2012 . The fastener ejection member is configured and dimensioned to be contacted by a distal end of a driver tube that is operatively connected to the advancing means  2006  through the body portion  2008  such that manipulation of the advancing means effectuates advancement of the driver tube to force the staple pushers into engagement with the plurality of surgical fasteners retained with in the fastener cartridge  2012  to causes ejection thereof. 
     The tool assembly  1004  ( FIG. 1 ) may also be adapted for use with a surgical stapling apparatus  3000  ( FIG. 11 ), such as that disclosed in commonly assigned U.S. Pat. No. 7,334,717, currently assigned to Tyco Healthcare Group LP, the contents of which are hereby incorporated by reference herein in its entirety. The surgical stapling apparatus  3000  includes a cartridge receiving half-section  3002 , which accommodates a plurality of surgical fasteners, and an anvil half-section  3004 . The half-sections  3002 ,  3004  are pivotally connected via handles  3006 ,  3008  for approximation during use. 
     Following approximation of the half-sections  3002 ,  3004 , the surgical fastener applying apparatus  3000  is fired by driving a firing slide  3010  distally through the advancement of a firing lever  3012 . Distal movement of the firing slide  3010  causes a plurality of cam bars to engage camming surfaces that interact with a plurality of pushers to expel the plurality of surgical fasteners from the cartridge receiving half-section  3002 . The surgical fasteners are positioned on either side of a track which guides a knife during longitudinal movement to thereby sever tissue along a cut-line. 
     The tool assembly  1004  ( FIG. 1 ) may also be adapted for use with a transverse anastomosis fastening instrument  4000  ( FIG. 12 ), such as that disclosed in commonly owned U.S. Pat. No. 5,964,394, currently assigned to United States Surgical Corporation, the contents of which are hereby incorporated by reference herein in its entirety. The surgical fastener applying apparatus  4000  includes an approximation lever  4001 , a movable handle  4002 , an elongated portion  4004  that extends distally from the handle  4002 , and an arm  4006  that extends from a distal end  4008  of the elongated portion  4004 . The surgical fastener applying apparatus  4000  further includes a tool assembly  4010  that includes an anvil  4012  that is orthogonally affixed to the arm  4006 , and a surgical fastener cartridge receiver  4014  that is operatively coupled to the distal end  4008  of the elongated portion  4004  for retention of the surgical fastener cartridge  200 . 
     Prior to firing of the surgical fastener applying apparatus  4000 , the approximation lever  4001  is actuated to distally advance a drive member that is operatively connected to the surgical fastener cartridge  200  to move the surgical fastener cartridge  200  towards the anvil  4012 , which remains stationary, and capture tissue therebetween. Thereafter, the handle  4002  is moved to advance a pusher bar distally through the elongated portion  4004  to cause corresponding movement of a head portion included at the distal end of the pusher bar. The head portion includes a plurality of fingers extending distally therefrom that are configured and dimensioned to engage the cartridge assembly to thereby discharge the plurality of surgical fasteners retained therein. Upon discharge, the surgical fasteners are driven through the tissue and into the anvil  4012  for formation. 
     It is also envisioned that the tool assembly  1006  ( FIG. 1 ) may also be adapted for use with any of the other surgical fastener applying apparatus discussed in commonly owned U.S. Pat. Nos. 6,045,560; 5,964,394; 5,894,979; 5,878,937; 5,915,616; 5,836,503; 5,865,361; 5,862,972; 5,817,109; 5,797,538; and 5,782,396, the disclosures of which are hereby incorporated by reference herein in their entirety. 
     In additional embodiments of the present disclosure, the surgical fastener applying apparatus may include a plurality of cam bars for interacting with the pushers to deploy the surgical fasteners. For example, the surgical fastener applying apparatus disclosed in U.S. Pat. No. 5,318,221, the disclosure of which is hereby incorporated by reference herein, in its entirety, has a cam bar adapter that holds a plurality of cam bars and a knife. A channel is advanced through operation of the handle of the apparatus, which drives the cam bars and knife forward. A clamp tube that surrounds the proximal end of the anvil is advanced to clamp the anvil and cartridge together. In another example, the surgical fastener applying apparatus disclosed in U.S. Pat. No. 5,782,396, the disclosure of which is hereby incorporated by reference herein, in its entirety, has an actuation sled. An elongated drive beam is advanced distally through operation of the handle of the apparatus, driving the actuation sled forward. The distal end of the drive beam engages the anvil and the channel that supports the cartridge as the drive beam travels distally, to deploy the staples and clamp the anvil and cartridge together. 
     In a further embodiment of the present disclosure,  FIG. 16  shows a cross-sectional view of a tool assembly  2004  having an anvil member  2100  and cartridge assembly  2200 . The fastener retention slots  2216  in the outer rows are sized to allow the surgical fasteners  100  to exit the slots  2216  at an angle. The anvil member  2100  has a plurality of forming recesses  2316  for each slot  2216 , to ensure formation of the fastener at one or more angled positions with respect to the vertical axis “Z-Z” of the surgical fastener cartridge  2202 . The fastener retention slots  2216  in the inner rows, adjacent the longitudinal knife slot  2217  of the surgical fastener cartridge  2202 , are sized so that the surgical fasteners  100  exit the retention slots  2216  in a substantially vertical orientation, i.e., along the vertical axis “Z-Z,” or at a smaller angle with respect to the vertical axis “Z-Z,” as compared to the surgical fasteners  100  in the outer rows of fastener retention slots  2216 . The surgical fasteners  100  in each row of fastener retention slots  2216  may be the same size, or alternatively, the surgical fasteners  100  in the in the outer rows of fastener retention slots  2216  may be larger in size when compared to the surgical fasteners  100  in the inner rows of fastener retention slots  2216 . For example, the surgical fasteners  100  in the in the outer rows of fastener retention slots  2216  may have longer leg lengths when compared to those of the surgical fasteners  100  in the inner rows of fastener retention slots  2216 . The tendency of tissue to extrude in a laterally outward direction with respect to the cartridge body  2202  will encourage the surgical fasteners  100  to angle outwardly, as shown in  FIG. 16 . 
     In certain embodiments, the anvil member  2100  is comprised of a plurality of plates  2130 , each having defined therein forming recesses  2316 , as shown in  FIGS. 17 and 18 . The plates  2130  are attached to one another so as to form the anvil member  2100 , e.g., via lamination. The forming recesses  2316  may be arranged so that more than one forming recess  2316  corresponds to a fastener retention slot  2216 . In this way, a surgical fastener  100  exiting a fastener retention slot  2216  will be directed into, and formed by, one of the forming recess  2316 , whether the surgical fastener  100  exits the fastener retention slot  2216  in a substantially vertical, or angled, fashion. 
     The above description, disclosure, and figures should not be construed as limiting, but merely as exemplary of particular embodiments. It is to be understood, therefore, that the disclosure is not limited to the precise embodiments described, and that various other changes and modifications may be effected by one skilled in the art without departing from the scope or spirit of the disclosure. Additionally, those skilled in the art will appreciate that the elements and features illustrated or described in connection with one embodiment can be combined with those of another, and that such modifications and variations are also intended to be included within the scope of the present disclosure.