Abstract:
A surgical fastener applying device having a handle with a trigger pivotably attached thereto and movable within a trigger plane. The trigger has a bottom portion extending from the handle and a top portion disposed within a housing of the handle. The device has a staple housing with a proximal end attached to the handle, a distal end extending therefrom and a longitudinal axis therebetween. The housing has a firing bar disposed within, and the trigger is coupled to the firing bar. The device has a link member with a first end pivotably attached to the top portion of trigger, the link member has a second end comprising a slidable pin. The pin engages a three dimensional cam path disposed within the housing. The link member follows distal and proximal movement of the top portion of the trigger, and the pin slides perpendicular to the trigger plane to follow the three dimensional cam path.

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. application Ser. No. 13/015,977 filed on Jan. 28, 2011; and is a continuation-in-part of U.S. patent application Ser. No. 13/015,966 filed on Jan. 28, 2011; and is a continuation-in-part of U.S. patent application Ser. No. 12/690,311 filed on Jan. 20, 2010; and is a continuation-in-part of U.S. patent application Ser. No. 12/690,285 filed on Jan. 20, 2010; and is a continuation-in-part of U.S. patent application Ser. No. 12/608,860 filed on Oct. 29, 2009; and is a continuation-in-part of U.S. patent application Ser. No. 12/609,336 filed on Oct. 30, 2009; and is a continuation-in-part of U.S. patent application Ser. No. 12/359,351 filed on Jan. 26, 2009; and is a continuation-in-part of U.S. patent application Ser. No. 12/359,354 filed on Jan. 26, 2009; and is a continuation-in-part of U.S. patent application Ser. No. 12/359,357 filed on Jan. 26, 2009. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates in general to surgical tissue fastening. The present invention also relates in general to surgical tissue fastening for the treatment of obesity and other metabolic diseases. The present invention has even further relation to powered and robotic surgery. 
     BACKGROUND OF THE INVENTION 
     Obesity is a medical condition affecting more than 30% of the population in the United States. Obesity affects an individual&#39;s quality of life and contributes significantly to morbidity and mortality. Obesity is most commonly defined by body mass index (BMI), a measure which takes into account a person&#39;s weight and height to gauge total body fat. It is a simple, rapid, and inexpensive measure that correlates both with morbidity and mortality. Overweight is defined as a BMI of 25 to 29.9 kg/m2 and obesity as a BMI of 30 kg/m2. Morbid obesity is defined as BMI≧40 kg/m2 or being 100 lbs. overweight. Obesity and its co-morbidities are estimated to cost an excess of $100 billion dollars annually in direct and indirect health care costs. Among the co-morbid conditions which have been associated with obesity are type 2 diabetes mellitus, cardiovascular disease, hypertension, dyslipidemias, gastroesophageal reflux disease, obstructive sleep apnea, urinary incontinence, infertility, osteoarthritis of the weight-bearing joints, and some cancers. These complications can affect all systems of the body, and dispel the misconception that obesity is merely a cosmetic problem. Studies have shown that conservative treatment with diet and exercise alone may be ineffective for reducing excess body weight in many patients. 
     A surgical procedure has been developed for involuting the gastric cavity wall to reduce stomach volume as a treatment for obesity. In the gastric volume reduction (GVR) procedure (e.g., reduction gastroplasty, gastric plication, greater curvature plication, anterior surface plication, etc.), multiple pairs of suture anchoring devices, such as T-Tag anchors, are deployed through the gastric cavity wall. Preferably, the suture anchors are deployed through a small diameter port in a minimally invasive surgical procedure to reduce trauma to the patient. Following deployment of the T-Tag anchors, the suture attached to each individual pair of anchors is cinched to approximate the tissue and secured to involute the cavity wall between the anchors. This procedure is described in greater detail in co-pending U.S. patent application Ser. Nos. 11/779,314, 11/779,322, 12/113,829, 12/179,600, 12/359,351, 12/609,336, and 12/690,311, which are hereby incorporated herein by reference in their entirety. Procedure variations of particular interest include the case where the involution occurs about the midline of the anterior surface of the stomach, the case where the involution occurs about the greater curvature of the stomach following the removal or relaxing of attachment points along the greater curve (e.g., dissection of the short gastric vessels, dissection of the omentum from the gastric wall, etc.), and combinations of these (e.g., the involution begins near the gastro-esophageal junction and extends about the greater curve and transitions to the anterior surface near the incisura angularis). Preclinical outcomes around fastener durability for gastric plication procedures in a canine model are discussed in Menchaca et al. “Gastric plication: preclinical study of durability of serosa-to-serosa apposition”.  Surg Obes Relat Dis  2011; 7:8-14. Clinical outcomes discussing different gastric plication procedures are discussed in Brethauer et al. “Laparoscopic gastric plication for the treatment of severe obesity”.  Surg Obes Relat Dis  2011; 7:15-22. One effect of the procedure is to more rapidly induce feelings of satiation defined herein as achieving a level of fullness during a meal that helps regulate the amount of food consumed. Another effect of this procedure is to prolong the effect of satiety which is defined herein as delaying the onset of hunger after a meal which in turn regulates the frequency of eating. By way of a non-limiting list of examples, positive impacts on satiation and satiety may be achieved by a GVR procedure through one or more of the following mechanisms: reduction of stomach capacity, rapid engagement of stretch receptors, alterations in gastric motility, pressure induced alteration in gut hormone levels, and alterations to the flow of food either into or out of the stomach. As an example, a stomach with a reduced capacity will distend more quickly for a given volume of food. This distension of the stomach may trigger stretch receptors which in turn trigger a sense of satiation. In another example, the procedure will limit the stomach&#39;s ability to expand, effectively reducing its capacity or fill volume. Additionally, the procedure may induce a beneficial hormonal effect due either to the more rapid triggering of stretch receptors in certain regions of the stomach or the prevention of hormone release by eliminating triggering mechanisms from being engaged in the infolded region that no longer experiences stretch in the same manner. In yet another example, the procedure may alter gastric emptying by preventing efficient antral contractions. Additionally, the infolded region may provide a restrictive inlet into the stomach just distal to the esophagogastric junction. The GVR procedures described in these applications require individual placement of each suture anchor pair into the cavity wall tissue, and subsequent tensioning of the suture between the anchor pairs in order to involute the tissue. This individual placement of the T-Tag anchors and manual suture tensioning is time intensive; increasing the duration, complexity and cost of the GVR procedure. Accordingly, it is desirable to have a simpler, faster, and less expensive means for forming a tissue fold within the peritoneal cavity. 
     It is known to use surgical staples for binding and holding body tissues together following an anastomosis, skin closure, or other surgical procedure. Traditionally, these staples have had a wide U-shape in the undeformed state, requiring a large incision site or wide diameter trocar cannula to accommodate the staples and stapler. Staples and staplers having a lower profile have been developed for use in smaller diameter (i.e. 5 mm or 10 mm) trocars. However, these devices suffer from a number of deficiencies which make them impractical for use in the GVR procedure. In particular, such staplers require bending the staple a full 180° from the pre-deployment, stacked condition in the stapler to the closed, deployed condition in the tissue. Obtaining this degree of plastic deformation requires that the staple be composed of a soft, ductile material, such as soft titanium. However, the use of a soft ductile material decreases the strength and holding power of the formed staple, thus making the staple unsuitable for the pressures associated with involuting the gastric cavity wall without an impractical number of staples. Staples having a triangular pre-firing configuration have also been developed for deployment through a low profile stapler. However, the triangular shape of these staples prevents the staples from being stacked and fed longitudinally through the stapler shaft. Instead, the staples are stacked and fed vertically within the stapler, which reduces the number of staples that can be deployed from the stapler while still maintaining a low profile diameter. Since some versions of the GVR procedure may require a large number of staples to involute the cavity wall, vertical stacking would necessitate using more than one stapler to complete a procedure. Additionally, previous staplers have bent staples at three or fewer points during formation and deployment, which reduces the amount of work hardening and, thus, strengthening within the formed staple. 
     Accordingly, to facilitate GVR and other surgical procedures, it is desirable to have an improved surgical staple and deploying stapler for fastening layers of tissue within the peritoneal cavity. It is desirable that the stapler has a low profile for use through a small diameter laparoscopic port, a single trocar containing multiple small laparoscopic ports, or through a semi-rigid or flexible endoscopic platform (e.g., for use in natural orifice surgical procedures), yet be capable of deploying staples with a large tissue purchase. Further, it is desirable that the staples have a folded, box shape, and that a large quantity of the staples be deliverable by a single stapler during a procedure. Additionally, it is desirable to have a stapler which alters the configuration of a staple from a low profile, reduced width prior to deployment to a wider, operable width following deployment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric view of an exemplary low profile surgical stapler of the present invention; 
         FIG. 2  is a top view of an exemplary staple embodiment shown in an initial, undeployed condition; 
         FIG. 3  is a top view of the staple of  FIG. 2  shown in an intermediate deployment condition; 
         FIG. 4  is a top view of the staple of  FIG. 2  shown in a final, deployed condition; 
         FIG. 5  is an exploded isometric view of the staple housing and deploying assembly for the stapler of  FIG. 1 ; 
         FIG. 6  is an exploded isometric view, partially in section, of the former, shoe and staple housing of  FIG. 5 ; 
         FIG. 7  is a side, partially sectional view of the distal end of the stapler handle; 
         FIG. 8  is an isometric view of the stapler of  FIG. 1 , shown with a portion of the left side of the handle casing detached; 
         FIG. 9  is an exploded isometric view of the stapler of  FIG. 8  shown with the left side of the handle casing removed; 
         FIG. 10  is an exploded isometric view of the right side of the stapler, showing a number of handle components, viewed from the lower proximal end of the stapler; 
         FIG. 11  is a more detailed, isometric view of the right side of the clamp yoke shown in  FIG. 10 ; 
         FIG. 12  is a side, partially sectional view of the distal end and handle of the stapler showing an initial deployment condition; 
         FIG. 13  is a side, partially sectional view of the distal end of the stapler showing the staple deploying assembly in an initial deployment condition; 
         FIG. 14  is a right side view of the proximal end of the stapler in an initial deployment condition, shown with the outer cover removed; 
         FIG. 15  is a side, partially sectional view of the distal end and handle of the stapler showing the actuator lobes pivoted distally to release the anvil latch; 
         FIG. 16  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 15 , with the anvil retracted proximally against the clamp; 
         FIG. 17  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 15 ; 
         FIG. 18  is a side, partially sectional view of the distal end and handle of the stapler showing the former, anvil and clamp in a proximal-most position; 
         FIG. 19  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 18 , with a staged staple being deposited into the discharge channel; 
         FIG. 20  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 18 ; 
         FIG. 21  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the actuator advances the clamp distally; 
         FIG. 22  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 21 , with the clamp contacting the back span of a staged staple; 
         FIG. 23  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 21 ; 
         FIG. 24  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the actuator advances the clamp and anvil distally; 
         FIG. 25  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 24 , with the clamp pushing the staged staple and anvil distally through the deployment opening; 
         FIG. 26  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 24 ; 
         FIG. 27  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the clamp and anvil are locked in a fully distal position; 
         FIG. 28  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 27 , with the fully distal clamp and anvil opening the staple outside the distal deployment opening; 
         FIG. 29  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 27 ; 
         FIG. 30  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the actuator is released open during a pause in the deployment sequence; 
         FIG. 31  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 30 , with the fully distal clamp and anvil holding the open staple outside the distal deployment opening; 
         FIG. 32  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 30 ; 
         FIG. 33  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the actuator is re-closing and pushing the former distally; 
         FIG. 34  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 33 , with the former advancing to close the staple outside the distal deployment opening; 
         FIG. 35  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 33 ; 
         FIG. 36  is a side, partially sectional view of the distal end and handle of the stapler showing a deployment condition in which the actuator pivots open to draw the former and clamp back proximally from the closed staple; 
         FIG. 37  is a side, partially sectional view showing the distal end of the stapler in the same deployment condition as  FIG. 36 , with the clamp and former drawn back proximally from the closed staple; 
         FIG. 38  is a right side view of the proximal end of the stapler with the outer cover removed, showing the same deployment condition as  FIG. 36 ; 
         FIG. 39  is a sectional, histological view at  8  weeks of a distal (pyloric) portion of a plication site from a canine model; 
         FIG. 40  is a sectional, histological view from a canine model showing a plication formed using a single suture attachment row; 
         FIG. 41  is a sectional, histological view at  8  weeks of a proximal (esophageal) portion of a plication site from a canine model; 
         FIG. 42  is a schematic, sectional view of the anterior surface of a gastric cavity following an LGCP procedure showing a plication formed with two attachment rows of staples; and 
         FIG. 43  is a schematic, sectional view taken along line  43 - 43  of  FIG. 42 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawing figures, in which like numerals indicate like elements throughout the views,  FIG. 1  illustrates an exemplary low profile fastener applying device or stapler for use in GVR and other small incision site surgical procedures in the peritoneal cavity including, but not limited to, reinforcement of staple lines (e.g., “over-sewing” of a vertical sleeve gastrectomy), closing of surgical defects (e.g., gastronomy closure), and fixation of temporary (e.g., liver retraction) or permanent (e.g., hernia mesh, gastric band securement) medical devices. As shown in  FIG. 1 , the stapler  10  includes a handle  12  having a pistol grip  14  shaped for grasping by a surgeon. A trigger or actuator  16  is pivotably attached to handle  12  to be drawn towards the pistol grip  14  in a trigger plane during staple deployment. An elongated staple housing  20  having a longitudinal axis extends distally from handle  12 . Housing  20  has sufficient length (on the order of 18″) to enable use within an obese patient at numerous trocar access sites for traditional laparoscopic approaches. Likewise, housing  20  is sized to allow for passage through a small (3-5 mm) diameter trocar, although functional devices of a larger diameter are also possible without departing from the overall scope of the invention. A staple deploying assembly is at least partially disposed within the interior of housing  20  for discharging staples from a distal deployment opening  22 . Staples are individually advanced outside of the open stapler end  22 , and expanded open through actuation of the handle. After the staple pierces or otherwise engages the tissue sections to be joined, the stapler draws the expanded staple legs back inward to close the staple through the tissue. 
     To obtain a large tissue purchase (which is desirable in GVR procedures) while using a small diameter delivery shaft, stapler  10  deploys fasteners or staples having a folded, closed loop configuration. These closed loop or “box” staples have a small width in the initial, unformed condition. The width of the staple is expanded during opening and forming to allow the staple to obtain a large tissue purchase.  FIG. 2  illustrates an exemplary box staple  30  for deployment from stapler  10 . Staple  30  comprises a length of wire formed into a crown or back span  32  and first and second leg portions  34 ,  36  that intersect with opposite ends of the back span. The wire has a cylindrical cross-section, but may have other shapes (e.g., rectangular, elliptical, etc.) to provide optimal strength for the application or to aid in the feeding of the staples, and may or may not be uniform along the length of the wire. Leg portions  34 ,  36  intersect with back span  32  at an approximate angle α of 90° and extend in a substantially parallel fashion forward of the back span. Opposite back span  32 , leg portions  34 ,  36  are bent inward to form staple end segments  40 ,  42 . In a loop shape, two lengths of wire may be disposed across one side of the shape to enclose the shape, as demonstrated by the end segments  40 ,  42 . Staple legs portions  34 ,  36  are bent at end segments  40 ,  42  to make one of the leg portions at least one wire diameter longer in length than the other leg portion. The longer length of one leg portion (i.e. staple leg  34  in  FIG. 2 ) enables the end segments  40 ,  42  to lie in a common plane with back span  32 . The tips of end segments  40 ,  42  are angled to form sharp prongs  46  for piercing tissue. 
       FIG. 3  shows staple  30  in a second, intermediate deploying condition. In this intermediate state, staple legs portions  34 ,  36  are bent outward to describe a maximum width between the distal tips of the staple legs. In  FIG. 3 , staple legs  34 ,  36  are shown expanded open approximately 180° into substantially lateral alignment with the initial back span position, with end segments  40 ,  42  projecting distally. However, it should be understood that staple legs  34 ,  36  can be expanded open to an angle less than or greater than 180°. Staple legs  34 ,  36  are bent outward by applying a deploying force (indicated by arrow  38  in  FIG. 2 ) to a mid section of back span  32  while the staple is held fixed inside at the intersections between the staple legs and back span. The application of force  38  against the opposite, fixed forces at the staple leg intersections pulls the staple legs  34 ,  36  outward, expanding open the staple, while substantially simultaneously indenting the center of the back span  32 . As staple legs  34 ,  36  are bent outward, back span  32  retains a non-linear characteristic. The outward bending of staple legs  34 ,  36  creates an enlarged opening into the staple  30  that is preferably in the range of twice the width of the stapler housing. Without a loss in generality, the width may be adjusted for different applications. As an example, the width may be smaller for applications such as mesh fixation. 
     Staple  30  is transformed to a third, fully deployed form, shown in  FIG. 4 , by the application of force to laterally spaced points along staple legs  34 ,  36 . This force application is indicated by arrows  44  in  FIG. 3 . In the final deployment condition, staple leg portions  34 ,  36  are drawn back towards the center of the staple, with prongs  46  again pointing inward through the intervening tissue to penetrate and hold the tissue. The length of staple  30  decreases between the initial and final deployment conditions, with an ensuing increase in the staple width, so that the final width dimension of the formed staple (described by the distance between staple legs  34 ,  36 ) is greater than the initial width dimension. During deployment, staple  30  transitions between the initial, intermediate, and final formed conditions in a series of steps which may be substantially simultaneous, but which are preferably carried out sequentially, so as to first open staple  30  to the intermediate condition of  FIG. 3 , and then bend each of the staple legs  34 ,  36  back around into the formed condition shown in  FIG. 4 . Staples used in this application are preferably biocompatible, implantable, and may optionally be absorbable. A non-limiting list of candidate materials includes: metals such as titanium and its numerous alloys, stainless steel, Nitinol, magnesium, and iron; plastics such as PEEK, Prolene™; absorbable materials such as PDS™, Vicryl™, and polylactic acid (PLA); and combinations of these materials or these classes of materials. Further, these fasteners may contain or be coated with therapeutic agents that are selectively or immediately released over time to aid in healing, prevent or minimize infection (e.g., triclosan, α-Lauroyl-L-arginine ethyl ester), reduce swelling or edema, etc. 
     The staple shown in  FIGS. 2-4  is intended to be one non-limiting example of a closed-form staple with substantially parallel legs. Additional detail regarding staple designs, as well as staple applicators, procedure applications, and methods of use are disclosed in co-pending U.S. patent application Ser. No. 12/359,351 filed Jan. 26, 2009 entitled “A SURGICAL STAPLER FOR APPLYING A LARGE STAPLE THROUGH A SMALL DELIVERY PORT AND A METHOD OF USING THE STAPLER TO SECURE A TISSUE FOLD”, co-pending U.S. patent application Ser. No. 12/359,354 filed Jan. 26, 2009, entitled “A SURGICAL STAPLER FOR APPLYING A LARGE STAPLE THROUGH A SMALL DELIVERY PORT AND A METHOD OF USING THE STAPLER TO SECURE A TISSUE FOLD”, co-pending U.S. patent application Ser. No. 12/359,357 filed Jan. 26, 2009 entitled “A SURGICAL STAPLER FOR APPLYING A LARGE STAPLE THROUGH A SMALL DELIVERY PORT AND A METHOD OF USING THE STAPLER TO SECURE A TISSUE FOLD”, co-pending U.S. patent application Ser. No. 12/608,860 filed Oct. 29, 2009, entitled “BOX STAPLE METHOD WHILE KEEPING SAID BACK SPAN IN SUBSTANTIALLY ITS ORIGINAL SIZE AND SHAPE”, co-pending U.S. patent application Ser. No. 12/609,336 filed Oct. 30, 2009, entitled “A METHOD FOR APPLYING A SURGICAL STAPLE”, and co-pending U.S. patent application Ser. No. 12/690,285 filed Jan. 20, 2010 entitled “APPARATUS FOR FEEDING STAPLES IN A LOW PROFILE SURGICAL STAPLER”, which are hereby incorporated herein by reference in their entirety. In applying the staple designs disclosed in the cited U.S. Patent Applications to the present invention, the staple designs would preferably include a non-linear back span. In addition to the staple designs disclosed herein, it is anticipated that other alternative staple designs may also be conceived and used with the present invention without departing from the scope of the invention. 
     Turning now to  FIG. 5 , which shows an exemplary staple deploying assembly for deploying staples  30  in accordance with the invention. As shown in  FIG. 5 , stapler  10  includes a staple former  50  attached to the distal end of staple housing  20  for forming and closing staples. Staple deployment opening  22  is located at the distal end of former  50 . Former  50  includes an inner channel (not shown) for conveying staples through the former and outside the stapler during deployment. Staples  30  are individually conveyed through former  50  and a distance outside of distal opening  22  by an anvil  52 . Anvil  52  includes a pair of longitudinally extending, inwardly biased spring arms having upwardly curved, staple holding tines  56  at the distal end. The proximal face of each anvil tine  56  is preferably rounded with an inward radius to aid in positioning and retaining a staple on the tines during deployment. These proximal faces may have a non-perpendicular angle (e.g., acute or undercut) to the plane of the fed staple to further aid in retaining the staple. Individual staples are held against the anvil tines during passage through the former  50 . The proximal end of anvil  52  is shaped for connecting the anvil to an anvil extension  54 . Anvil extension  54  extends proximally from anvil  52 , through housing  20 , and inside handle  12 . 
     A staple firing bar or clamp  60  extends substantially along the surface of anvil  52 . Clamp  60  comprises an elongated strip having substantially planar upper and lower surfaces and a width slightly narrower than the width of the unformed staples  30 . Clamp  60  preferably has as small a length as necessary to cover the anvil  52 . The distal end of clamp  60  is shaped for mating engagement with staple back span  32  for engaging and pushing the staple through former  50 . The distal end of clamp  60  is angled inwardly to a center tip at approximately a 45° angle relative to the longitudinal stapler axis, although lesser or greater angles may be used to vary the opening size of the staple. The angled clamp tip includes an inward radius for mating against the outer circumference of the staple back span  32 . Anvil  52  combines with the distal face of clamp  60  and former  50  to form the discharge channel of the staple deploying assembly. During the deployment sequence, clamp  60  advances distally within the discharge channel to deform the back span of a staged staple and thereby open the staple. 
     The proximal end of clamp  60  is attached to a driving assembly in handle  12  via a clamp extension. The clamp extension includes an upper section  64  and a lower section  66 . Upper clamp extension  64  comprises an elongated, planar strip supporting a staple stack  70 . A longitudinally-extending trough  72  is located midway across the width of upper extension  64 , beneath staple stack  70 , and extends from the distal end beyond the proximal end of the staple stack. Lower clamp extension  66  has an elongated, grooved surface to accommodate trough  72 . A staple driving member comprising a substantially rigid, cylindrical rod  74  is retained within trough  72  in a spaced relationship from the plane of staple stack  70 . A plurality of outwardly projecting staple advancers  76  are evenly spaced apart substantially along the length of rod  74 . Staple advancers  76  extend to at least the proximal end of staple stack  70  to ensure that a staple advancer engages the proximal-most staple in the stack. The proximal end of staple driving rod  74  is curved at approximately a 90° angle relative to the longitudinal rod axis to form a control pin  80 . 
     Rod  74  is retained within trough  72  so as to translate distally and then back proximally with the clamp extension during each staple deployment. Additionally, rod  74  rotates within trough  72  about the longitudinal rod axis. Upper clamp extension  64  includes a plurality of notches spaced apart along a side of trough  72 . The notches are aligned with staple advancers  76  to allow the advancers on rod  74  to rotate out of trough  72  and above the surface of the clamp extension. The distal end of rod  74  extends through an open distal end of trough  72  into clamp  60 . The staple advancer at the distal end of rod  74  is located in a groove in the proximal end of clamp  60 . Rod  74  rotates relative to clamp  60 , with the distal-most staple advancer extending up through a notch in the clamp. Rod  74  and the attached staple advancers  76  are advanced and retracted by the clamp extension to index staple stack  70  distally approximately one staple length during each staple deployment. 
     A staple guide  82  is located proximal of former  50  inside staple housing  20 . The outer perimeter of staple guide  82  is shaped to conform to the inner circumference of staple housing  20  to enable the staple guide to extend concentrically within the staple housing. Staple guide  82  is fixed at a proximal end within the stapler handle  12  by a key  78  to prevent translation of the guide along the longitudinal housing axis during staple deployment. Distal housing bushing  106 , into which key  78  extends, includes two notches  108  located  180  degrees apart on the circumference of bushing  106  to permit the staple guide  82  to rotate with staple housing  20  about the longitudinal housing axis for positioning the staple prongs  46 . A slot  87  is formed in staple housing  20  adjacent guide key  78 . Guide key  78  extends up through slot  87  to allow staple housing  20  to translate along the longitudinal housing axis relative to the fixed staple guide  82 . 
     Staple guide  82  includes a plurality of flexible, longitudinally-spaced anti-backup arms  83  (shown in  FIG. 13 ) extending in the direction of staple stack  70 . The anti-backup arms flex in and out of contact with the staples in stack  70  to prevent the stack from moving proximally within the staple housing during the staple deployment sequence. Proximal of the anti-backup arms, a closed, contoured guide path (not shown) is formed into the surface of staple guide  82  facing control pin  80 . Control pin  80  extends into and rides along the guide path to translate staple driving rod  74  relative to the fixed staple guide  82 . While control pin  80  transverses the guide path, the angular direction of the pin changes. The directional changes of control pin  80  rotate rod  74  within trough  72 . As rod  74  rotates, staple advancers  76  are rotated from a position inside trough  74  to a position above the surface plane of upper clamp extension  64 . Above clamp extension  64 , the staple advancers  76  rotate up into the closed loops of the staples in stack  70 . The guide path includes a forward track, in which control pin  80  pivots to rotate stapler advancers  76  up inside the loops of staples  30  to advance the staple stack; and a return track, in which control pin  80  pivots to rotate the staple advancers down into trough  72  to allow the staple advancers to retract beneath the advanced staple stack, back to the initial position. 
     Staple stack  70  extends longitudinally through housing  20 , between staple guide  82  and clamp extension  64 , in a plane parallel to the longitudinal axis of the housing. Staples  30  are conveyed within stack  70  to the distal end of the stapler prior to deployment. Within stack  70 , each staple  30  is oriented such that the abutting end segments  40 ,  42  of the staple are positioned nearest the open stapler end  22 . Within the staple stack, staples may be spaced apart from other staples, in contact with other staples, or alternate between states of contact and spaced. The legs  34 ,  36  of each staple  30  are aligned substantially parallel to and may be in contact with the walls of staple guide  82  to maintain the forward orientation of the staples. Any number of staples  30  can be included within stack  70 , with the preferred stapler embodiment capable of holding  20  or more staples to facilitate procedures, such as GVR, which require a large number of tissue appositions or junctions. The distal end of staple stack  70  is conveyed along the surface of clamp  60  prior to the dropping of the individual staples onto anvil  52  for deployment. 
     Staple stack  70  is adjacent to the inner surface of staple guide  82  to enable the anti-backup arms  83  to contact the staples within the stack. As shown in  FIGS. 5 and 6 , a staple transporter or shoe  84  extends from the distal end of staple guide  82  into former  50  for transferring staples from stack  70  onto anvil  52 . Shoe  84  is cantilevered between staple guide  82  and former  50  with the pivot point at the proximal end within the staple guide. The distal end of shoe  84  flexes to index a single, distal-most staple in stack  70  from the surface of clamp  60  into a staging position on anvil  52  during each deployment sequence. The proximal end of shoe  84  is shaped to facilitate movement of staples beneath the shoe as the stack  70  is advanced through housing  20  beneath staple guide  82 . The staple advancer  76  at the distal end of staple driving rod  74  pushes the next staple in the stack  70  under shoe  84  during each deployment cycle. Shoe  84  includes a C-channel, indicated at  86 , through which the distal end of staple stack  70  passes. The lower sides of C-channel  86  are co-planar with the staple conveying surface of clamp  60  to pass the staple stack  70  through the channel as the stack is advanced along the surface of the clamp. C-channel  86  aids in maintaining staple alignment at the distal end of stack  70 , and prevents the distal-most staple in the stack from prematurely tilting into the discharge channel during retraction of clamp  60 . 
     During the staple deployment process, clamp  60  moves distally through the discharge channel, advancing against the back span of a staple  30 , and pinning the staple between the distal clamp tip and anvil tines. As clamp  60  advances, the distal end of shoe  84  flexes up against a downward bias by the contact between the advancing clamp and the proximal sloped surfaces of shoe side rails  88 . As the distal-most staple moves underneath shoe side rails  88 , the side rails push the staple legs  34 ,  36  down onto clamp  60 . The staple remains in this position, between shoe  84  and clamp  60 , and against the proximal face of former  50 , during the opening and forming of the previous staple. When clamp  60  retracts following staple forming, shoe  84  pushes the staple downward into the discharge channel between the distal clamp face and retracting anvil tines, thereby staging the staple for the next deployment sequence. In the present invention, the staple deploying components within housing  20  are substantially the same size as the pre-deployment staples  30 , in order to maximize the staple size and, thus, tissue purchase during deployment, while maintaining a small (3-5 mm) profile for the stapler. The distal deployment opening  22  in former  50  is sized to allow clamp  60 , anvil  52 , and the deploying staple  30  to pass outside of the former during the deployment process, while the proximal face of the former serves as an end stop for staple stack  70 . Additional details regarding the staple deploying assembly can be found in U.S. patent application Ser. No. 12/359,351 entitled “A SURGICAL STAPLER FOR APPLYING A LARGE STAPLE THROUGH A SMALL DELIVERY PORT AND A METHOD OF USING THE STAPLER TO SECURE A TISSUE FOLD” and U.S. patent application Ser. No. 12/690,285 entitled “METHOD AND APPARATUS FOR FEEDING STAPLES IN A LOW PROFILE SURGICAL STAPLER”, which have been previously incorporated into this application by reference. 
     In a surgical application, stapler  10  is manipulated through a trocar (in a laparoscopic procedure) or flexible endoscopic platform (in natural orifice, endoluminal or transluminal procedures) so that deployment opening  22  is adjacent to the tissue area to be fastened. Staple housing  20  may be rotated relative to handle  12  to change the orientation of deployment opening  22 . As shown in  FIG. 7 , one manner of rotating housing  20  is by way of a knob  90  connected about the circumference of the housing. Knob  90  includes a flange  92  which rotates within a slot at the distal end of handle  12 . The location of flange  92  within the handle slot allows rotation of knob  90  about the longitudinal housing axis, while preventing the knob from translating along the axis. As knob  90  is rotated, housing  20  is in turn rotated by a connection between the housing and the knob. A connection also exists between knob  90  and the staple deploying assembly inside of housing  20  to rotate the deploying assembly in conjunction with the housing about the longitudinal housing axis. Accordingly, as housing  20  rotates, the legs of staple  30  rotate relative to the surrounding tissue, thereby altering the position at which the staple prongs will pierce the tissue during deployment. 
     As shown in further detail in  FIGS. 5 and 7 , staple housing  20  may be formed of two separate sections, identified as  94 ,  96 , connected by an adjustment member, such as a castle nut  100 . The distal housing end, identified at  94 , has a threaded end which is screwed into the distal end of nut  100 . The proximal housing end, identified at  96 , also has a threaded end which is screwed into the opposite, proximal end of nut  100 . One end of nut  100  has right-handed threads while the opposite end has left-handed threads. The opposite threading allows the two housing sections  94 ,  96  to be adjustably connected together via the nut  100 . Either section  94  or  96  of the staple housing can be rotated relative to nut  100  to increase or decrease the effective longitudinal length of the housing. Adjusting the effective length of housing  20  in turn alters the distance which staples are conveyed outside the housing distal opening  22  by anvil  52 . Adjusting the length of staple housing  20  during assembly of the stapler  10  provides tolerance for slight manufacturing deviations that might otherwise adversely affect the forming and closing of staples at distal deployment opening  22 . 
     Nut  100  includes a plurality of longitudinally extending grooves  102  evenly spaced apart around the outer circumference of the nut. The inner circumference of rotating knob  90  has at least one longitudinally extending rib (not shown) sized to fit within grooves  102 . After staple housing  20  is adjusted via nut  100  to the proper deployment length, the nut is rotated slightly to align the nearest nut groove  102  with a groove  104  on the exterior of distal housing bushing  106  (shown in  FIG. 9 ). Knob  90  is then connected over nut  100  and distal housing bushing  106 , with ribs inside the knob aligned with and engaging grooves  102  on nut  100  and grooves  104  on bushing  106 . The interaction of the knob rib with the nut and bushing grooves locks the angular position of nut  100 , and thereby fixes the longitudinal length of the staple housing  20 . The interconnection between the knob rib and nut groove also enables the knob to rotate the housing about the longitudinal housing axis as described above. Stapler  10  is depicted as having a rigid housing  20  for open surgical applications or laparoscopic applications using trocars. However, in alternative embodiments housing  20  may also include at least one articulation joint allowing the housing to deflect in a controlled manner from the primary axis, or be substantially flexible and of an increased length allowing for less invasive, natural orifice (e.g., transoral, transvaginal, etc.) access to regions of the patient requiring a treatment (e.g., within the peritoneal cavity of the patient). In each of these configurations, it is conceived that the device may also be compatible with a single trocar containing multiple ports. 
     Turning now to  FIGS. 8-10  which show the proximal, handle end of stapler  10  in an initial deployment position. Handle  12  includes a housing  110  comprising an outer cover with an interior molded frame integrally formed with the cover. Casing  110  may be formed from a plastic or other similar material, in sections which are joined together during the manufacturing process by any of a number of suitable means known in the art. The proximal end  96  of staple housing  20  extends into handle  12 , through distal bushing  106 , and includes a former bushing  112  at the proximal end. A former return spring  114  encircles housing  20  between the distal face of former bushing  112  and the proximal end of distal bushing  106 . Staple guide  82  extends proximally through housing  20  into handle  12 . A staple guide stop  116  (shown in  FIG. 5 ) is located at the proximal end of staple guide  82 . Staple guide stop  116  holds staple guide  82  stationary with respect to handle  12 . Lower clamp extension  66  extends proximally into handle  12  through former bushing  112 . The proximal end of lower clamp extension  66  includes a clamp bushing  120 . A clamp return spring  122  surrounds clamp extension  66  between clamp bushing  120  and a clamp spring stop  126  (shown in  FIG. 12 ). 
     Clamp bushing  120  is mounted within the frame of a clamp yoke  124 . As shown in greater detail in  FIG. 11 , clamp yoke  124  includes a clamp lockout member, identified at  128 , on a side opposite clamp bushing  120 . Clamp lockout member  128  includes a lockout spring  130  which interacts with a lockout tongue  131  on housing casing  110  (shown in  FIG. 14 ) during the staple deployment sequence. The interaction of lockout spring  130  and tongue  131  prevents a stapler jam in the event that actuator  16  is fired too quickly. Clamp yoke  124  also includes a proximal clamp stop  132  which engages a stop in the handle frame to hold clamp  60  in a proximal-most position. As shown in  FIGS. 9-10 , a clamp L-latch  134  is located beneath yoke  124  and pivots about a pin  136 . An L-latch spring  138  biases L-latch  134  in the direction of yoke  124 . 
     Anvil extension  54  extends proximally through the open end of housing  20  and beyond clamp bushing  120 . The proximal end of anvil extension  54  includes an anvil stop  140 , shown in  FIG. 8 , with a proximally-extending anvil release member  142 . An anvil spring  144  extends between anvil stop  140  and a distal stop, indicated at  146  in  FIG. 10 , formed into the frame of handle  12 . An opening  150  is located in the proximal end of the handle cover for external, operator access to anvil release  142 . 
     Actuator  16  includes a distally facing trigger grip  152  extending outside handle housing  110 . Opposite trigger grip  152 , actuator  16  is divided into a pair of lobes  154  extending up into the body of handle  12 . An anvil latching lever  160  is pivotally connected by a pin between the upper ends of lobes  154  to extend proximally from the actuator. A pair of pins  162  extend laterally from the proximal end of anvil latching lever  160  into a cam path  164  shaped into the interior sides of handle casing  110 . Pins  162  are driven along cam path  164  by the motion of actuator  16 . Between pins  162 , latching lever  160  includes a flexible latching arm  170  having a proximally-extending, tabbed end. A transfer wheel  172  having a plurality of outwardly-extending pawls rotates about a pin adjacent to anvil latching lever  160 . In the initial deployment condition shown in  FIG. 12 , one of the transfer wheel pawls engages the tab at the proximal end of flexible latching arm  170 . The contact between the latching arm  170  and transfer wheel  172  rotates the wheel as the latching lever  160  is driven distally along cam path  164 . A second pawl on transfer wheel  172  contacts the distal end of a proximal clamp latch  180 . In the initial position shown in  FIG. 12 , proximal clamp latch  180  holds clamp yoke  124  in a forward position. A clamp latch spring  182  biases clamp latch  180  down into the locking position. A third pawl of transfer wheel  172  is positioned adjacent a mating detent on an anvil latch  184 . An anvil latch spring  186  is attached to the proximal end of anvil latch  184  to bias the latch into an initial locking position, in which the latch applies a distal force against anvil stop  140  to hold the anvil forward against the force of anvil return spring  144 . 
     A link member  190  is also pivotally connected between the actuator lobes  154 , below anvil latching lever  160 , as shown in  FIGS. 8-10 . Link member  190  extends distal of actuator lobes  154  within the handle  12 . The opposite, unattached end of link member  190  includes two laterally extending pins  192  which are biased, with, for example, a spring, to continuously engage three-dimensional transfer cam path  194 . Pins  192  engage a three-dimensional transfer cam path  194  formed into the interior of handle housing  110 . Link pins  192  slide within cam path  194  perpendicular to the trigger plane, following the circuitous path loop, as actuator  16  is twice squeezed closed and reopened to deploy a staple. The movement of pins  192  about cam path  194  drives the advancing and retracting of the clamp and former during the staple deployment sequence. Cam path  194  includes a series of four different steps or elevation changes to transition link  190  between the different stages in the deployment sequence, as will be described in more detail below. Actuator  16  includes cam surfaces  200  shaped into the distal faces of lobes  154 . Actuator cams  200  are proximally spaced from but aligned to make contact with the proximal face of clamp bushing  120  when the trigger grip  152  is squeezed towards pistol grip  14 . A former lever  202  is mounted between former bushing  112  and link member  190  to pivot about a pin  204  formed into the handle casing  110 . Former lever  202  includes a cam surface that is longitudinally aligned with former bushing  112  to apply a distally directed force to the bushing when the lever is pivoted in the distal direction. 
     Actuator  16  pivots about a pin  210  that extends through actuator  16  between trigger grip  152  and lobes  154 . As shown in  FIGS. 10 and 12 , actuator  16  includes a handle lockout feature comprising a plurality of ratchet teeth, indicated at  212 , ending in a distal release notch  214 . A spring-loaded pawl  216  is connected to the frame of pistol grip  14 . Teeth  212  are angled to catch pawl  216  as the teeth move proximally over the pawl. Pawl  216  engages successive ratchet teeth  212  as trigger grip  152  is squeezed, to prevent a premature reopening of actuator  16  in the absence of a squeezing force. As actuator  16  pivots to a fully-closed position against pistol grip  14 , teeth  212  move proximally beyond pawl  216 , pushing the pawl into release notch  214 . At release notch  214 , the top of pawl  216  rotates clockwise against the angle of teeth  212 , allowing the pawl to slide over the teeth back to a proximal-most position. A return spring  220  is connected between actuator  16  and pistol grip  14  for biasing the actuator into an open position. Return spring  220  is connected so that the spring expands as actuator  16  is squeezed closed. Spring  220  returns actuator  16  to an open condition as pawl  216  reaches release notch  216 , and the squeezing force on the trigger grip  152  is released. 
     In the initial deployment position shown in  FIGS. 12-14 , the upper lobes  154  of actuator  16  are in a proximal-most position, with anvil latching lever  160  in a proximal-most position engaging transfer wheel  172 . Anvil latch  184  is in a down position with the latch arm pushing against anvil stop  140  to hold the anvil in a distal-most position, as shown in  FIG. 13 , in which anvil tines  56  extend outside distal deployment opening  22 . Proximal clamp latch  180  is also in a downward position in contact with the proximal end of clamp yoke  124  to hold clamp  60  in a forward position, inside deployment opening  22 , and beneath the distal-most staple in stack  70 . Shoe side rails  88  push the distal-most staple down against the upper surface of clamp  60 , while the next staple in stack  70  is held within C-channel  86  on the upper surface of the clamp. Clamp lockout spring  130  is positioned on the upper surface of lockout tongue  131 , as shown in  FIG. 14 , and L-Latch  134  is pushed down by the distal end of clamp yoke  124 . In this initial position, link member  190  is also at a proximal-most position within transfer cam path  194 . Former lever  202  is pivoted away from former bushing  112 , allowing former return spring  114  to fully expand, and former  50  to be retracted back proximally from anvil tines  56 . 
     To deploy a staple  30 , stapler  10  is inserted through a small diameter port or flexible endoscopic platform to reach the desired tissue area inside a body cavity. At the appropriate tissue location, stapler end  22  is placed adjacent the tissue or tissue fold to be stapled, with rotating knob  90  being turned as necessary to position the staple prongs  46 . With stapler  30  appropriately positioned against the targeted tissue area, trigger grip  152  is manually squeezed in the direction of pistol grip  14  to begin the staple deployment sequence. As trigger grip  152  is squeezed actuator  16  pivots about pin  210 , causing the upper lobes  154  to pivot distally within the handle. The distally moving lobes  154  pull anvil latching lever  160  distally within anvil cam path  164 . As latching lever  160  moves distally, latching arm  170  pulls on the first transfer wheel pawl, causing the wheel to rotate. As transfer wheel  172  rotates, the second pawl on the wheel begins to apply a downward force to proximal clamp latch  180 . The downward force is initially insufficient to overcome clamp latch spring  182  and release clamp  60  back proximally. Simultaneously, the third transfer wheel pawl applies a proximal force to the detent on anvil latch  184 . The force on the anvil latch detent overcomes the force of anvil latch spring  186 , pivoting the latch up and out of contact with anvil stop  140 , as shown in  FIG. 15 . As anvil latch  184  pivots away from anvil stop  140 , the anvil stop is released to move proximally under the force of anvil spring  144 , drawing anvil tines  56  back inside of distal deployment opening  22  and against the distal clamp face, as shown in  FIG. 16 . Clamp  60  remains locked in position by proximal clamp latch  180 , thereby preventing additional proximal movement by anvil  52 . As actuator lobes  154  pivot distally, link member  190  also begins to drive pins  192  distally up the first leg of cam path  194 , as shown in  FIG. 17 . 
     As actuator lobes  154  continues pivoting distally, anvil lever  160  moves further distally within anvil cam path  164 , rotating transfer wheel  172 . The rotating wheel  172  applies increased force to the proximal end of clamp latch  180 , overcoming the force of clamp latch spring  182 , and releasing clamp yoke  124  to retract proximally under the force of clamp return spring  122 , as shown in  FIG. 18 . Clamp yoke  124  draws clamp  60  proximally until proximal clamp stop  132  bottoms out against the handle frame, as shown in  FIG. 20 . Anvil  52  retracts proximally with the clamp  60  until anvil stop  140  reaches the proximal end stop in the housing frame, as shown in  FIGS. 18 and 20 . In this fully retracted position, the tip of clamp  60  is proximal of the distal-most staple in stack  70  and anvil tines  56  are spaced distally forward of the clamp tip. The retracted position of clamp  60  allows shoe  84  to push the distal-most staple down into the discharge channel and over anvil tines  56 , as shown in  FIG. 19 . The proximal stop of clamp yoke  124  positions clamp bushing  120  at the distal face of actuator cams  200 . 
     The proximal movement of clamp yoke  124  also drives lockout spring  130  up and over the proximal tip of lockout tongue  131 , as shown in  FIG. 20 . As the lockout spring  130  drops below lockout tongue  131 , the clamp lockout member  128  resets inside clamp yoke  124 , allowing the clamp yoke to advance beneath the adjoining frame of the housing casing during subsequent steps in the deployment sequence. In the event that actuator  16  is moved very rapidly, the actuator cams  200  can, in some cases, prevent the clamp yoke  124  (and thus clamp  60 ) from fully retracting to the proximal end stop. In this event, clamp  60  will remain forward within the discharge channel and prevent the staged staple from dropping properly into the channel. If the staged staple does not drop properly into the discharge channel, a staple jam can occur when the clamp  60  advances distally. To prevent this possibility, lockout spring  130  will get held and fail to drop below lockout tongue  131  on the housing casing if the actuator  16  is moved too quickly. In this event, the lockout spring  130  will keep the lockout member  128  lifted above the surface of the clamp yoke  124 , thereby preventing the clamp yoke from advancing distally beneath the adjoining section of the casing frame indicated at  222 . To reset the device for normal function, the user fully releases trigger grip  152 , causing lockout spring  130  to drop below lockout tongue  131 , and restarting the staple firing sequence. 
     As actuator lobes  154  continue pivoting distally from the squeezing force on trigger  152 , cam surfaces  200  apply a distal driving force against clamp bushing  120 , as shown in  FIG. 21 . The distal force advances clamp  60  through the discharge channel and into contact with staple back span  32 , as shown in  FIG. 22 . As clamp  60  begins advancing, staple driving rod  74  rotates staple advancers  76  above the surface of clamp extension  64 . Staple advancers  76  push staple stack  70  distally as the clamp advances. In addition, the movement of lobes  154  drives link member  190  forward up the first leg of transfer cam path  194 . At the proximal handle end, anvil latching lever  160  continues moving distally along anvil cam path  164 . Anvil latching arm  170  advances distally beyond the first pawl of transfer wheel  172 , as shown in  FIG. 23 , disconnecting the lever  160  from the transfer wheel, and preventing further rotation of the wheel. The release of transfer wheel  172  allows the proximal end of clamp latch  180  to pivot downward under the force of clamp latch spring  182 . This positions the clamp latch  180  to engage the proximal face of clamp yoke  124  as the yoke advances distally beyond the latch. 
     Actuator cams  200  continue pushing clamp bushing  120  distally against the force of clamp return spring  122 , advancing clamp yoke  124 , and allowing clamp latch  180  to pivot down behind the proximal end of the clamp yoke. The distal movement of lobes  154  drives link member  190  within cam path  194 , dropping the link pins  192  from the first to the second path leg as shown in  FIGS. 24 and 26 . As clamp  60  advances distally within the discharge channel, the inward radius at the distal clamp tip engages the back span  32  of the staged staple and pushes the staple against the proximal face of the anvil tines  56 , holding the staple back span fixed between the clamp and anvil tines. As actuator  16  continues applying force to clamp bushing  120 , clamp  60  drives the staple  30  and anvil  52  forward through the open stapler end  22 , as shown in  FIG. 25 . As anvil tines  56  and the staged staple  30  progress through the distal stapler opening, the anvil tines remain inwardly biased, adjacent the intersection between the staple legs  34 ,  36  and back span  32 . With staple  30  held outside the open stapler end by clamp  60  and anvil tines  56 , anvil stop  140  bottoms out against the handle casing, as shown in  FIG. 27 , stopping further distal movement of anvil  52 . Anvil latch  184  pivots down into contact with the proximal face of anvil stop  140  to hold the anvil  52  forward outside the open stapler end. 
     When anvil  52  reaches its fully distal position, as shown in  FIG. 28 , the back span of staple  30  is firmly held between the tip of clamp  60  and the proximal face of anvil tines  56 . After anvil  52  reaches its distal stop, actuator  16  continues advancing clamp bushing  120  and, thus, clamp  60  relative to the fixed anvil tines. As clamp  60  advances, the clamp tip moves between anvil tines  56 , pushing the tines outward against the inside surfaces of staple  30  at the intersections between staple legs  34 ,  36  and back span  32 . The advancing clamp tip applies a distally directed force against staple back span  32  between anvil tines  56 . The distally directed force of clamp  60  drives the anvil arms out laterally and deforms back span  32  between the anvil tines. The deforming force of clamp  60  against the fixed back span  32  drives the anvil tines  56  laterally into staple legs  34 ,  36 , expanding open the staple  30 . As staple  30  is expanding open, staple legs  34 ,  36  are bent back against the distal angled face of clamp  60 . The angle at which staple legs  34 ,  36  bend open can vary, depending in part upon the angle of the clamp distal tip. As staple  30  expands open from its initial, closed-form shape, prong tips  46  move from an inward, overlapping position to the open, spread position described above, producing an increased width dimension in the staple. The substantial increase in width between the closed, folded staple condition and the open, expanded staple condition enables the staple to obtain a substantial tissue purchase while utilizing a small diameter delivery shaft. 
     Clamp  60  opens staple  30  at the distal end of the clamp advancement. At this point, L-latch  134  springs up into engagement with clamp yoke  124  to lock the clamp forward, with the staple pinned between the clamp and anvil tines. The link member  190  has advanced to the distal end of the second leg of the cam path  194 , as shown in  FIGS. 27 and 29 . The distal advance of clamp yoke  124  has also pulled clamp lockout spring  130  back around the distal end of the lockout tongue  131 . As staple  30  expands open, actuator  16  pivots to a fully closed position, with lockout pawl  216  advancing to release notch  214 . At release notch  214 , lockout pawl  216  pivots free of the ratchet teeth  212 , allowing actuator  16  to pivot open under the force of actuator return spring  220 . As actuator  16  reopens, link member  190  is drawn back down the second leg of cam path  194 . A step between the first and second cam path legs prevents link pins  192  from reversing back into the first leg of the path. At the proximal end of the second cam path leg, the link pins  192  drop over another step into the proximal end of the third path leg, as shown in  FIGS. 30 and 32 . At this point in the deployment sequence, actuator  16  does not return to the fully open, initial position due to the more proximal location of the link pins  192  in the cam path  194 . Anvil link pins  162  retract within anvil cam path  164  as actuator  16  pivots open. However, because the actuator  16  does not return to the fully open, initial position, latching arm  170  and transfer wheel  172  remain disconnected. With staple  30  fully expanded and stabilized between clamp  60  and anvil tines  56 , as shown in  FIG. 31 , the release of actuator  16  provides a pause in the deployment process to allow the surgeon to manipulate the open, exposed staple  30  to pierce or otherwise engage the intended tissue. 
     After the prongs  46  of the expanded staple  30  have been inserted at the desired tissue locations, the staple is formed through the tissue by again applying squeezing pressure to trigger grip  152 . The pressure on grip  152  pivots actuator  16 , causing link member  190  to advance distally within the third leg of transfer cam path  194 . As link member  190  advances distally, the link applies force against the former lever  202 , which in turn pushes against former bushing  112 , as shown in  FIGS. 33 and 35 . The force of link member  190  drives the bushing  112  forward, compressing former return spring  114 . Former bushing  112  pushes housing  20  distally relative to the fixed staple deploying assembly, with slot  87  sliding past guide key  78  as the housing advances relative to the fixed staple guide  82 . Housing  20  moves former  50  distally, drawing grooves at the distal end of the former against the expanded staple legs  34 ,  36 . The expanded staple is held fixed relative to the moving former  50  by clamp  60  and anvil tines  56 . The distal pushing force of former  50  against the expanded staple legs  34 ,  36  forces the legs to bend forward about the fixed anvil tines  56 , closing the staple, as shown in  FIG. 34 . 
     In the finished, closed shape, the width of the staple is greater than the previous, undeployed width, due to the different bending points along the staple length. This change in staple width enables the staple to have a low profile during delivery and a larger profile when formed through tissue. As staple legs  34 ,  36  are bending forward, prongs  46  are drawn back inward, grabbing onto the tissue or material in the spread between the prongs. As prongs  46  move inward, staple ends  40 ,  42  traverse an arc through the tissue, drawing the tissue into the closing staple. As prongs  46  reach an inward, preferably overlapping position, in which the staple  30  passes through the gripped tissue, former  50  reaches its distal-most position. Inside handle  12 , handle lockout pawl  216  advances over ratchet teeth  212 , preventing distal movement of former  50  until the former is in a distal-most position, as shown in  FIG. 35 . At the distal-most position, lockout pawl  216  reaches release notch  214 , enabling actuator  16  to pivot back open under the force of return spring  220 . 
     As actuator  16  pivots open, as shown in  FIGS. 36 and 38 , actuator lobes  154  rotate back, pulling link member  190  back proximally, and dropping link pins  192  from the third to the fourth leg of transfer cam path  194 . As link member  190  moves proximally, the force against former lever  202  is removed, allowing the lever and former bushing  112  to retract proximally from the release of compression in former return spring  114 . As former  50  retracts, key  78  moves to the distal end of housing slot  87 , and former  50  is drawn away from the closed staple  30 , as shown in  FIG. 37 , releasing the staple from the former. As link member  190  continues moving back proximally through the fourth leg of cam path  194 , the link pushes against the distal angled face of clamp L-latch  134 , as shown in  FIG. 36 . The contact with L-latch  134  pushes the latch down from clamp yoke  124 , as shown in  FIG. 38 . Clamp yoke  124  then retracts back into contact with proximal clamp latch  180 , pulling clamp  60  back proximally inside former  50 . As clamp  60  retracts, control pin  80  rotates staple advancers  76  down into clamp extension through  72 . The staple advancers  76  retract back beneath the staple stack  70 , leaving the stack in a distally indexed condition. Staple guide arms  83  hold the individual staples in stack  70  distally as the clamp extension retracts beneath the staples. As clamp  60  retracts proximally, the anvil arms retract back inward within the closed staple  30 , releasing the pressure of anvil tines  56  against staple legs  34 ,  36 . The formed staple  30  remains locked in the tissue (not shown), and held against anvil tines  56  outside the open stapler end  22 . With the anvil arms retracted, staple  30  can be released from the stapler by maneuvering the anvil  52  away from the staple. As actuator  16  pivots fully open, link pins  192  reach the proximal end of the transfer cam path  194 , resetting the link member back to the initial deployment position shown in  FIGS. 12 and 14 . Actuator  16  opens fully to the initial deployment position, and the stapler  10  resets back to the initial deployment condition, with the distal-most staple in stack  70  again staged between shoe side rails  88  and clamp  60  in preparation for the next deployment sequence. 
     If anvil tines  56  retract back inside former  50  before staple  30  is released, the anvil  52  can be pushed out distally by inserting a forceps or similar tool into the proximal handle opening  150 . Through opening  150 , the forceps can push against anvil release member  142  to drive anvil stop  140  distally. Release member  142  is configured with a concave surface to receive the forceps or similar tool. Other geometries may also be employed to engage the tool. Release member  142  can be pushed until anvil stop  140  is again locked forward by anvil latch  184 , to hold the anvil tines  56  outside the open end  22  of the stapler. Release member  142  provides an alternative, mechanism for advancing anvil  52  independent of actuator  16 . 
     After the staple  30  is released from anvil  52 , stapler  10  is preferably moved to a second targeted location along an intended fold line in a cavity wall or tissue apposition. Additional staples are preferably deployed along the cavity wall to extend the length of the fold. Additional details regarding GVR procedures and the use of a stapling device, such as the staple deploying device of the present invention, in a GVR procedure; as well as other surgical applications for the stapling device of the present invention, can be found in commonly assigned U.S. patent application Ser. No. 12/359,351, which was previously incorporated by reference into this application. 
     As mentioned above, one of the many beneficial applications for stapler  10  is forming plications in a gastric volume reduction (GVR) procedure such as a laparoscopic greater curvature plication (LGCP). The previously referenced article by Menchaca et al. discloses an LGCP procedure for using different fasteners and patterns for creating durable plications in a canine model.  FIG. 39  shows a histological view from Menchaca et al. depicting a first attachment pattern in which multiple rows of suture were used to form a durable plication. In  FIG. 39 , reference numeral  390  indicates the locations or spaces where suture was placed in forming the plication. The internal tunica muscularis  392  is denoted by the region containing the letter ‘M’, and the external tunica muscularis  394  is denoted by the region containing the letter ‘m’. The serosa surfaces have been replaced with a dense collagen scar  396  denoted by the region containing the letter ‘S’.  FIG. 40  shows a second histological view from Menchaca et al. In  FIG. 40 , fibrous healing  400  of the plication is evident on the exterior (serosa) surface of the stomach. The mucosa  404  is denoted by the region containing the letter ‘M’ and the submucosa  406  is denoted by the region containing the letters ‘SM’. The tunica muscularis  408  is denoted by the region containing the letters ‘TM’. In contrast to  FIG. 39 , a serosa space, indicated by  402 , is present within the region of the fold. The plication in  FIG. 40  was formed with a single row of suture in an interrupted pattern. The single row of suture had a spacing of 2-3 cm. Menchaca et al. states that “Intermittent point failures in serosa apposition occurred in those dogs that had received only 1 row of fasteners; in regions of the fold not containing fasteners, the serosa surfaces had not bonded”. Thus, while  FIG. 40  shows exterior serosa healing at  400 , this healing was intermittent and did not occur consistently along the length of the plication. 
       FIG. 41  shows an unpublished histological view from a similar study performed with the stapler described in this application. In this study, three attachment lines or rows of staples were used to create a plication in a canine model. As shown in  FIG. 41 , in this study the folded gastric wall was fused together by chronic inflammation/fibrosis  410  denoted by the region containing the letter ‘F’ at the base of the fold (base of the pre-existing serosa). The procedure was performed using a coarse 2-3 cm spacing between staples on the inner two attachment rows and an approximately 1 cm spacing between staples on the outermost attachment row. This study showed two areas of serosa fusion in the fold interior, as indicated at  412 , aside from the region of fibrosis  410  which corresponded to the outermost or final row of staples. Regions of the fold remained unbounded between the staple attachment lines, resulting in free space, as indicated at  414 , but no intermittent point failures were observed at the exterior (serosa) surface. Thus, the pattern from the study shown in  FIG. 41  is uniquely more durable than that described in Menchaca et al due to the elimination of point failures which created unintended exterior serosa spaces. Further, that this durability was achieved with the presence of free space between the attachment rows allows for easier reversal of this procedure as tissue dissection planes are easily identified. This is a significant advantage noted by potential patients of this procedure or any other bariatric surgical procedure. 
     It is envisioned that performing an LGCP procedure similar to the study shown in  FIG. 41  on a human patient, using stapler  10  described above, will comprise the following steps. The patient is placed in a supine position and a five trocar port technique is set up, typically using five 5 mm ports, to access the exterior of the gastric cavity. A Veress needle technique or Hassan technique can be utilized to establish pneumoperitoneum. A 5 mm trocar is placed above the umbilicus and slightly to the right of midline. The laparoscope is inserted and the abdomen is inspected. Trocars are then placed in the following locations under direct visualization: a 5 mm trocar in the right upper quadrant, a 5 mm trocar in the right upper quadrant below the 10 mm trocar at the auxiliary line, a 5 mm trocar below the xiphoid appendices, and a 5 mm trocar in the left upper quadrant. Percutaneous graspers and magnetically guided camera systems may be used to reduce the number of trocars used in this procedure. The greater curvature is then freed from its attachment points. The dissection starts at the distal body of the stomach along the greater curvature and continues proximally to the Angle of His. The left crus should be seen and the fundus mobilized off of the left crus. The dissection is then continued distally along the greater curvature to within 4-6 cm of the pylorus. Posterior gastric adhesions can be taken down as needed. Care should be taken to ensure that the dissection occurs approximately 0.5-1.0 cm from the greater curvature to avoid thermal damage to the gastric wall. 
     As shown in  FIGS. 42 and 43 , in the LGCP procedure of the present invention a plication is formed along the greater curvature preferably using at least 2 separate attachment lines or rows of staples. To create the attachment rows of staples, an endoscope, bougie, or other specialized intraluminal or extraluminal sizing device may be inserted into the patient and/or the cavity  420  to provide visibility and sizing. The greater curvature is folded into the interior of the cavity  420  beginning at the angle of His, indicated at  422 , and continuing to within 4-6 cm of the pylorus  424 . The greater curvature is folded by grasping and piercing the exterior surface of the cavity and targeting the muscularis of the gastric wall with the exposed staple prongs. A first one of the staple prongs is inserted into the exterior surface of the cavity on one side of the greater curvature. The greater curvature is then infolded into the interior of the cavity as the second staple prong is drawn into contact with the cavity exterior wall on the opposite side of the greater curvature. As the staple is formed the staple prongs are pulled inwardly, piercing the muscularis, and securely apposing adjoining serosa surfaces. The first staple is preferably placed approximately 2 cm from the Angle of His. The first attachment row of staples is indicated by arrows  430 . Approximately 10 staples are preferably used (depending on the geometry of the stomach) in this first attachment row, with the spacing between the staples maintained at approximately 2-3 cm. When creating plications, care must be taken not to obstruct at the EG junction and the angularis incisura as these are the two most common sites of obstruction. Intraoperative endoscopy, bougies with features, pressure based measurement systems, etc. may be used to aid in the sizing of the plication during its formation. 
     To create the second attachment row of staples, indicated by arrows  432 , the tissue grasping and staple forming process is repeated starting near the Angle of His  422 . Tissue is grasped using a staple prong inserted on the first side of the previously formed attachment line. The second staple prong is then inserted into the exterior cavity wall on the opposite side of the previous attachment line, to draw the two sections of the cavity wall together about the original attachment line and, thereby, form a second fold about the first fold along the greater curvature. The second attachment line is continued, forming a second fold about the first fold, to extend the plication to the vicinity of the pylorus  424 . In the embodiment shown in  FIGS. 42 and 43 , the second attachment line  432  is intended to be the final, outermost row of staples, and the spacing between the staples is preferably no greater than 1 cm. It is conceived that approximately 30 staples should be in this outermost row for an average sized human stomach. The 1 cm spacing has been determined by the inventors to provide the optimum serosa to serosa contact for uniform healing. Staple spacing of greater than 2 cm on the outermost row leads to deterioration of the serosa attachment and point failures. The inner attachment row provides for easier, quicker stapling of the outermost row, as well as greater serosa contact for more effective, uniform, exterior serosa fusion. Two areas of serosa fusion are formed corresponding to the attachment rows, and regions of free space  414 , shown in  FIG. 43 , are created inside the first attachment row and between the two rows. The 1 cm or less spacing in the outermost row provides for the development of uniform serosa adhesion along the outer edge of the fold, as indicated at  434  in  FIG. 43 . After the second, outer attachment row is in place, a leak test with methylene blue can be performed, or an insufflations test with the endoscope can be used, to check for a leak. While the procedure is described with an outer attachment line spacing of no more than 1 cm, it is conceived that the spacing between staples in the outer attachment line could be expanded to no greater than 2 cm, while still maintaining the desired serosa to serosa attachment and uniform adhesion. Other grasping methods such as the use of babcocks or other grasping instruments may be used to facilitate this procedure. 
     To complete the laparoscopic greater curvature plication (LGCP) procedure described herein, and in the previously referenced article by Brethauer et al, using stapler  10 , it is envisioned that the stapler should be able to fire at least forty staples without the need for reloading the device. Additionally, as mentioned above, it is conceived that stapler  10  will have beneficial application in many other procedures and will have the capability of firing at least twenty staples during these procedures without the need for reloading the device. Applying an approximate spacing of 1 cm along a significant portion of the greater curvature of the stomach with a sutured pattern requires significant time and skill. The stapler of the present invention, when used with the GVR plication pattern of the present invention (e.g., at a minimum employing at least one row with approximately 1 cm spacing on the outermost row), provides unique and unforeseen advantages over existing technology. A durable plication can be more quickly and easily formed using the stapler  10  than with traditional suturing methods. Stapler  10  allows for simulating an interrupted suture pattern with uniform external adhesion along the fold line, without the presence of intermittent point failures. The resulting plication with the presence of free space between the attachment lines facilitates easier reversal with standard laparoscopic techniques. 
     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, ethylene oxide (EtO) gas, 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. 
     In addition to reconditioning, stapler  10  of the present invention may also be reloaded with an additional stack of staples for use in multiple different surgical procedures. To reload the stapler, the distal end  94  of the staple housing is unscrewed from castle nut  100 . Housing  20  is removed to expose the inner components of the staple deploying assembly. Staple guide  82  and clamp extension  64  are then separated and a new staple stack  70  laid in position between the two parts. After the stack of staples is loaded, the staple guide and clamp extension are repositioned on opposite planar surfaces of the stack. The staple housing  20  is then slid back over the staple deploying assembly and reattached at the proximal end to castle nut  100 . Staple housing  20  can be adjusted via castle nut  100 , as described above, to obtain the optimal staple housing length for opening and forming staples during deployment. 
     Any patent, publication, application 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. 
     The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described in order to best illustrate the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. The handle described above could easily be removes and replaced with a means for attaching the device to a surgical robot. In addition, the device could be power operated through the use of batteries or other known power sources. It is intended that the scope of the invention be defined by the claims appended hereto.