Anvil assembly and delivery system

[0001] Technical Field

[0002] The present disclosure relates to an anvil assembly for use with a surgical stapling device. More particularly, the present disclosure relates to an anvil assembly and a system for trans-oral delivery of the anvil assembly.

[0003] Background of Related Art

[0004] Anastomosis is the surgical joining of separate hollow organ sections to allow the sections to communicate with each other. Typically, an anastomosis procedure follows surgery in which a diseased or defective section of hollow tissue is removed and the remaining end sections are to be joined. Depending on the desired anastomosis procedure, the end sections of the hollow organ may be joined using circular, end-to-end, end-to-side, or side-to-side organ reconstruction methods.

[0005] In a circular anastomosis procedure, the two ends of the organ sections are joined by means of a surgical stapling instrument which drives a circular array of staples through the organ end sections and cores and removes any overlapping tissue to free a tubular passage. In some applications of a circular anastomosis procedure, an anvil rod having an attached anvil head is mounted to the distal end of a surgical stapling instrument shaft prior to insertion of the instrument into the tissue to be anastomosed. However, in other applications, a detachable anvil rod may be mounted to the instrument subsequent to positioning of the surgical stapling instrument and the anvil assembly within respective tissue sections. In such instances, the surgical stapling instrument and the anvil assembly are separately delivered to the operative site. Each tissue end section is then secured to a respective anvil or staple holding component, e.g., by a purse string suture. The anvil assembly is mounted to the surgical stapling instrument by inserting a mounting portion of the anvil rod within the distal end of the surgical stapling instrument so that a mounting mechanism within the surgical stapling instrument securely engages the anvil rod. Preparation of the tissue sections to be joined and mounting of the anvil rod to the surgical stapling instrument may be performed using minimally invasive surgical techniques, i.e., under laparoscopic guidance.

[0006] An anvil assembly delivery system for delivering an anvil assembly trans-orally to a surgical site, e.g., the stomach, is disclosed in commonly owned U.S. Pat. No. 8,109,426, the content of which is incorporated herein by reference in its entirety. As described, a guide suture is threaded through openings in the head of the anvil assembly to facilitate trans-oral insertion of the anvil assembly and to allow retrieval of the anvil assembly prior to attachment of the anvil assembly to the surgical stapling instrument. At any point during the stapling procedure, the guide suture may be detached from the anvil assembly by pulling the guide suture back through the openings in the anvil head.

[0007] To prevent premature detachment of the guide suture from the anvil assembly during trans-oral insertion, it would be beneficial to have an anvil assembly that is configured such that the guide suture remains attached to the anvil assembly until the stapling procedure is compete, i.e., after the tissue to be anastomosed has been stapled and cut.

[0008] In accordance with the present disclosure, an anvil assembly is provided for use with a surgical stapling instrument for performing end-to-end anastomosis of tissue. The anvil assembly includes an anvil center rod, and a head assembly pivotally secured to the anvil center rod about a pivot axis and movable between an operative position and a tilted position. The head assembly includes an anvil head and a cutting ring disposed within the anvil head. The anvil head defines first and second openings and the cutting ring defining a slot in alignment with the first and second openings.

[0009] In one embodiment, the first and second openings and the slot are dimensioned to receive a suture. The anvil center rod may include first and second slide members. The first slide member may be pivotally connected to the head assembly on one side of the pivot axis by a first drive link and the second slide member being connected to the head assembly on the other side of the pivot axis by a second drive link. The first slide member may be movable in relation to the second slide member to effect movement of the head assembly between the operative position and the tilted position. The anvil assembly may further include a biasing member positioned to urge the first slide member in relation to the second slide member to position the head assembly in the tilted position. The biasing member may be positioned between the first member and the second slide member to urge the first and second slide members apart.

[0010] Also provided is an anvil delivery system including an anvil assembly and a suture guide assembly. The suture guide assembly includes a guide suture secured to the head assembly and a reel assembly configured for selectively dispensing the guide suture. The guide suture may be received through the first opening in the anvil head, passes through the slot in the cutting ring, and extends from the second opening in the anvil head. The reel assembly may include a housing and a reel member rotatably received within the housing. The guide suture may be supported about the reel member. The reel member may define an annular channel for receiving the guide suture. The housing may define an annular cavity. The reel member may be rotatably supported on the housing within the annular cavity.

[0011] In some embodiments, the anvil delivery system may further include a tubular guide assembly for trans-oral insertion of the anvil assembly. The tubular guide assembly may include a flexible tube and an adapter configured for operably connecting the flexible tube to the anvil center rod. The tubular guide assembly may further include a retaining suture for retaining the head assembly of the anvil assembly in the tilted position. The retaining suture may be received through third and fourth openings in the anvil head and may be secured between the adapter and the flexible tube.

[0012] Also provided is an anvil delivery kit. The kit including an anvil assembly, a suture guide assembly including a guide suture and a reel assembly, and a tubular guide assembly including a flexible tube and an adapter.

[0042] Embodiments of the presently disclosed surgical stapling device, anvil assembly, and anvil delivery system will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. As is common in the art, the term “proximal” refers to that part or component closer to the user or operator, i.e. surgeon or clinician, while the term “distal” refers to that part or component further away from the user.

[0043] Referring to FIGS. 1 and 2, a surgical stapling instrument including an anvil assembly according to the present disclosure is shown generally as stapling device 10. Briefly, stapling device 10 includes a proximal handle assembly 12, an elongated central body portion 14 including a curved elongated outer tube 14a, and a distal head portion 16. Handle assembly 12 includes a stationary handle 18, a firing trigger 20, a rotatable approximation knob 22, and an indicator 24. A pivotally mounted trigger lock 26 is fastened to handle assembly 12 and is manually positioned to prevent inadvertent firing of stapling device 10. Indicator 24 is positioned on the stationary handle 18 and includes indicia, e.g., color coding, alpha-numeric labeling, etc., to identify to a surgeon whether the device is approximated and is ready to be fired. Head portion 16 includes an anvil assembly 100 and a shell assembly 30. The structure and function of stapling device 10 will only be described to the extent necessary to fully disclose the operation of anvil assembly 100. For a more detailed description of an exemplary stapling device, please refer to commonly owned U.S. Pat. No. 7,364,060, (“the '060 patent”) the content of which is incorporated herein by reference in its entirety.

[0044] Although a manual handle assembly is described, the surgical stapling device may be a powered (e.g., motor operated) surgical instrument, or part of a robotic surgical system, in any of the embodiments disclosed herein.

[0045] With reference now to FIGS. 3 and 4, distal end portion 16 of stapling device 10 includes shell assembly 30 which is secured to a distal end of the central body portion 14, a pusher 40 extending distally through central body portion 14, and an anvil retainer assembly 50 extending through pusher 40 and shell assembly 30. Although not shown, anvil retainer assembly 50 is operably connected to an approximation mechanism of stapling device 10 which is actuated by the rotatable approximation knob 22 (FIG. 1), and pusher 40 is operably connected to a firing mechanism of stapling device 10 which is actuated by the firing trigger 20 (FIG. 1). For a more detailed description of the approximation mechanism and/or the firing mechanism of the stapling device 10, see the '060 patent which has been incorporated herein by reference.

[0046] Shell assembly 30 includes a shell or housing 32, a pusher back 34, a staple guide 36, a cylindrical knife 38 (FIG. 25), and a plurality of staples “S”. Shell 32 includes an outer housing portion 32a and an inner housing portion 32b (FIG. 3). Staple guide 36 is supported in the distal end of outer housing portion 32a and includes an annular array of staple receiving pockets 36a for housing staples “S”. Pusher back 34 is slidably supported in shell 32 between outer housing portion 32a and inner housing portion 32b and includes a plurality of fingers 34a which are each slidably received in respective staple pockets 36a in staple guide 36. Pusher back 34 includes a pair of recesses 35 which receive detents 42a formed on flexible fingers 42 of a pusher 40 to secure pusher 40 to pusher back 34 such that pusher back 34 is movable with pusher 40 from a retracted position to an advanced position to eject staples “S” from staple guide 36.

[0047] In any of the embodiments disclosed herein, the shell assembly may be configured as a removable and replaceable assembly. In this way, after the staples are fired, the shell assembly can be replaced, providing a new set of staples, even staples of a different size or configuration, and a fresh knife.

[0048] An elongated hollow bushing 44 is fixedly retained in inner housing portion 32b of shell 32 using, e.g., screw threads, a friction fitting, or the like. Bushing 44 defines a channel 45 through which anvil retainer assembly 50 and anvil center rod 160 reciprocate during approximation and separation of anvil assembly 100 and shell assembly 30. Bushing 44 provides additional strength to inner housing portion 32b of shell 32 to prevent separation of the anvil assembly 100 and anvil retainer assembly 50 during firing of the stapling device 10.

[0049] Anvil retainer assembly 50 includes a two-part assembly having a body portion 52 defining a longitudinal throughbore 53 and a trocar or locking member 54 slidably received within longitudinal throughbore 53. Longitudinal throughbore 53 includes a stepped portion or shoulder 53a (FIG. 3).

[0050] Trocar 54 includes an annular flange or shoulder 54a on a proximal end and a blunt tip 54b on a distal end. Tip 54b of trocar 54 extends from the distal end of body portion 52 of anvil retainer assembly 50 and is movable within throughbore 53 of body portion 52 from an advanced position to a retracted position. A biasing member, e.g., a coil spring 56, is positioned between annular flange 54a and shoulder 53a of longitudinal bore 53 (FIG. 3). The biasing member 56 urges trocar 54 to its retracted position. The proximal end of trocar 54 includes a transverse slot 55 having a pin or rod 58 extending therethrough. Pin 58 is slidably positioned within longitudinal slots 55 formed in body portion 52. The distal and proximal ends of slots 51 define the advanced and retracted positions of trocar 54, respectively.

[0051] Body portion 52 of anvil retainer assembly 50 includes an annular protrusion 60 and defines a longitudinal slot 61. Annular protrusion 60 facilitates attachment of anvil assembly 100 to anvil retainer assembly 50 as will be discussed in further detail below. A cam member 62 is pivotally supported about a pivot member 64 in slot 61 at a position proximal of pin 58. Cam member 62 includes a distal finger 62a having an angled face and a recess 63 positioned proximally of finger 62a for receiving pin 58 of trocar 54. Pin 58 is urged by coil spring 56 towards finger 62a. Engagement between the angled face of finger 62a and pin 58 urges cam member 62 to pivot about pivot member 64 to allow pin 58 to move into recess 63.

[0052] Referring now to FIGS. 5-7, anvil assembly 100 is configured for releasable attachment to stapling device 10 (FIG. 1). Anvil assembly 100 includes a head assembly 102 and a rod assembly 104. Head assembly 102 is pivotally secured to rod assembly 104 and is configured to selectively move between a tilted position (FIG. 5) and an operative position (FIG. 21).

[0053] With particular reference to FIG. 7, head assembly 102 includes an anvil head 110, an anvil post 120, a cutting ring 130, a cover 140, and an anvil plate 150. Rod assembly 104 includes an anvil center rod 160, a first slide member 170, a second slide member 180, first and second link members 190, 192 pivotally connecting first and second slide members 170, 180 of rod assembly 104 with anvil post 120 of head assembly 102, and a spring member 196 for biasing first and second slide members 170, 180 relative to each other.

[0054] With reference still to FIGS. 5-7, anvil head 110 of head assembly 102 defines a centrally located throughbore 111 configured to receive anvil post 120, an inner annular recess 113 configured to receive cut ring 130, and an outer annular recess 115 configured to receive anvil plate 150. Inner annular recess 113 and outer annular recess 115 are separated by an annular flange 116 defines a notch 116a. Anvil head 102 further defines a first set of openings 117a configured to receive a first or retaining suture “S₁” and a second set of openings 117b configured to receive a second or guide suture “S₂”. As will be described in further detail below, first suture “S₁” is a component of tubular guide assembly 202 of anvil delivery system 200 and second suture “S₂” is a component of suture guide assembly 204 of anvil delivery system 200.

[0055] Anvil post 120 is configured to be secured within throughbore 111 of anvil head 110. Anvil post 120 defines lateral slot 121 configured to accommodate first and second link members 190, 192, a large transverse bore 123 extending across longitudinal slot 121 for receiving a pivot member 106, and a pair of small transverse bores 115a, 115b extending across longitudinal slot 121 for receiving pivot pins 106a, 108a, respectively. Pivot member 106 pivotally connects anvil post 120 to a distal end 160b of center rod 160 via a cooperating bore 163 formed in center rod 160. In one embodiment, pivot member 106 includes a pin or post which defines a transverse axis which is spaced laterally from the longitudinal axis “x” defined by center rod 160 such that anvil head 110 can pivot approximately ninety degrees (90°) from an operative position (FIG. 21) in which a plane defined by tissue contacting surface 152 of anvil plate 150 of head assembly 102 is substantially perpendicular to the longitudinal axis “x” of center rod 160 to a tilted reduced profile position (FIG. 28) in which head assembly 110 is substantially parallel to longitudinal axis “x” of center rod 160. Alternately, other types of pivot members at a variety of locations in relation to longitudinal axis “x” of center rod 160 may be incorporated into anvil assembly 100. Pivot pins 106a, 108a pivotally connect first and second links 190, 192 of rod assembly 104 with anvil post 120.

[0056] Referring also to FIGS. 5 and 7, cutting ring 130 defines a throughbore 131 configured to be positioned about anvil post 112 and has a radial slot 133 configured to align with first set of openings 117a in anvil head 110. When cutting ring 130 is received within inner annular recess 113 of anvil head 110, radial slot 133 is configured to accommodate second suture “S₂” of suture guide assembly 204 of anvil delivery system 200 which is received through the second set of openings 117b. Cover 140 defines a throughbore 141 and is configured to be received between cutting ring 130 and anvil plate 150. Cover 140 may be formed of Mylar® or other protective material.

[0057] Anvil plate 150 includes a tissue contacting surface 152 defining a plurality staple forming recesses 153. Anvil plate 150 further includes a tab 154 configured to be received within a slot 115a formed in anvil head 110. Tab 154 and slot 115a cooperate to position anvil plate 150 in the proper orientation within outer recess 115 of anvil head 110.

[0058] Referring to FIGS. 5-7, center rod 160 of rod assembly 104 includes proximal and distal ends 160a, 160b and defines a throughbore 161. As shown, proximal end 160a includes at least one opening 165 configured to receive a suture or the like to facilitate positioning of anvil assembly 100 within a hollow organ. A distal end of throughbore 161 (see FIG. 18) is configured to slidably receive at least a portion of each of first and second slide members 170, 180.

[0059] With particular reference to FIG. 7, first slide member 170 of rod assembly 104 includes a substantially annular body having an open proximal end 170a and a closed distal end 170b and defining a throughbore 171 extending between proximal and distal ends 170a, 170b. Throughbore 171 is configured to accommodate spring member 196. First slide member 170 further defines a longitudinal cut-away 173 which extends between proximal and distal ends 170a, 170b and is in communication with throughbore 173. Cutaway 173 is configured to accommodate second slide member 180 such that first and second slide members 170, 180 may slide relative to each other. Distal end 170b of first slide member 170 includes a radially outward extending flange 172 defining a transverse bore 175 configured to receive pivot pin 106b. Pivot pin 106b secures a first end 190a of first link 190 of rod assembly 104 to the first slide member 170. A second end 190b of first link 190 is secured with anvil post 120 of head assembly 102 by a pivot pin 106a. Distal end 170b further includes a nub 174 extending proximally within throughbore 171 configured to support and align a distal end 196b of spring member 196 within throughbore 171.

[0060] Second slide member 180 of rod assembly 104 is configured for longitudinal movement relative to first slide member 170. Second slide member 180 includes a longitudinal body having a closed proximal end 180a, an open distal end 180b, and is configured to be received in the cut-away 173 of first slide member 170. As noted above, this configuration permits sliding of first slide member 170 in relation to second slide member 180. A radially outward extending flange 182 extends along a majority of the length of second slide member 180 and defines a transverse bore 185 configured to receive pivot pin 108b for securing second link 192 of rod assembly 104 with anvil post 120 of head assembly 102. A proximal end 180a of second slide member 180 includes a distally extending nub 184 which supports and aligns a proximal end 196a of spring member 196 within throughbore 171.

[0061] A spring or biasing member, e.g., coil spring 196, is positioned between first and second slide members 170, 180 to urge the slide members apart or away from each other. First or drive link 190 is pivotally connected at a proximal end 190a to second slide member 180 by pivot pin 106a and is pivotally connected at a distal end 190b to anvil post 120 by pivot pin 106b. Second or return link 192 is pivotally connected at a proximal end 192a to first slide member 170 by pivot pin 108a and is pivotally connected at a distal end 192b to anvil post 120 by pivot pin 108b. First and second links 190, 192 are connected to slide members 170, 180 and anvil post 120 in such a manner that when biasing member 196 urges first and second slide members 170, 180 apart, anvil head 110 pivots about pivot member 106 to its tilted reduced profile position (FIG. 28).

[0062] Center rod 160 includes a plurality of flexible arms 164 which defines a proximal end of throughbore 161 and is configured to releasably engage a removable trocar, adaptor and/or the annular protrusion 60 of the body portion 52 of the anvil retainer assembly 50. A plurality of splines 166 are formed about center rod 160. Splines 166 mesh with grooves (not shown) formed in stapling device 10 (FIG. 1) to properly align anvil assembly 100 in relation to shell assembly 30 (FIG. 3) of stapling device 10 during approximation of anvil assembly 100 and shell assembly 30.

[0063] In any of the embodiments disclosed herein, the pivoting anvil assembly, which includes a head assembly and a rod assembly, may be arranged differently. For example, see the tilting anvil assembly disclosed in U.S. patent application Ser. No. 13/915,953, the disclosure of which is hereby incorporated by reference herein in its entirety.

[0064] With reference now to FIGS. 8 and 9, anvil assembly 100 is shown operably connected to a system for delivering anvil assembly 100 within a patient “P” (FIG. 25) shown generally as anvil delivery system 200. Anvil delivery system 200 includes a tubular guide assembly 202 and a suture guide assembly 204. Each of tubular and suture guide assemblies 202, 204 are selectively secured to anvil assembly 100 to facilitate trans-oral positioning of anvil assembly 100 within a patient. As will be described in further detail below, tubular guide assembly 202 is configured to be manually detached from anvil assembly 100 prior to attachment of anvil assembly 100 to stapling device 10 (FIG. 1) and suture guide assembly 204 is configured to be automatically detached from anvil assembly 100 following the stapling stroke of the stapling device 10 (FIG. 1).

[0065] With reference now to FIGS. 8-12, tubular guide assembly 202 includes a flexible tube 210 for trans-oral positioning of anvil assembly 100 within a patient “P” (FIG. 20) and an adapter 220 for connecting flexible tube 210 to anvil assembly 100. Flexible tube 210 includes an open end 210a for supporting adapter 220 and a closed end 210b configured for trans-oral receipt in a patient. Open end 210a of flexible tube 210 defines a throughbore 211 configured to receive a locking pin 214. Open end 210a further includes an opening 213. Flexible tube 210 may include markings or other gradations 216 (FIG. 11) along the length thereof to indicate to a surgeon the depth of insertion of the flexible tube 210 within the patient during tran-oral positioning of anvil assembly 100 within a patient and/or to indicate the length of flexible tube 210 remaining in the patient during removal.

[0066] Adapter 220 includes a first end 220a configured to be received within open end 210a of flexible tube 210 and a second end 220b configured to be received within bore 161 formed in center rod 160 of anvil assembly 100. A first end 220a of adapter 220 includes a series of annular rings 222 configured to frictionally retain first end 220a of adapter 220 within open end 210a of flexible tube 210. A second end 220b of adapter 220 includes a longitudinal guide member 224 configured to be received between two adjacent flexible arms 164 of center rod 160 of anvil assembly 100. Second end 220b of adapter 220 is sized to allow center rod 160 of anvil assembly 100 to freely slide onto and off of second end 220b of adapter 220. Adapter 220 further defines a first throughbore 221 formed in a central hub portion 226 as well as second and third throughbores 223, 224 formed in first end 220a. Throughbore 223 is configured to align with throughbore 211 formed in open end 210a of flexible tube 210 and is sized to receive locking pin 214. Throughbore 223 is configured to receive both ends of the first suture “S₁.” Throughbore 221 can also receive the suture ends to enhance retention. For a more detailed description of an exemplary tubular guide assembly including a flexible tube and an adapter, please refer to commonly owned U.S. Pat. No. 8,109,426, the content of which is incorporated by reference herein in its entirety.

[0067] In order to secure anvil assembly 100 on tubular guide assembly 202 of anvil delivery system 200, first suture “S₁” is threaded through openings 117a formed on anvil head 110 such that first and second ends of first suture “S₁” are positioned on different sides of center rod 160. Second end 220b of adapter 220 is positioned within throughbore 161 of center rod 160 such that longitudinal guide 224 (FIG. 10) of adapter 220 is received between two arm members 164 (FIG. 7) of center rod 160. Each of the first and second ends of first suture “S₁” is then inserted through throughbore 223 formed in adapter 220. Anvil head 110 is then rotated to a first tilted position against the bias of spring 196 and the first and second ends of first suture “S₁” are pulled through opening 223 to apply tension on anvil head 110 to retain anvil head 110 in the first tilted position as shown in FIG. 12.

[0068] After first suture “S₁” is tensioned to retain anvil head 110 in the first tilted position, first end 220a of adapter 220 is inserted into open end 210a of flexible member 210. The frictional contact between annular rings 222 of first end 220a of adapter 220 and an inner surface of flexible tube 210 secures adapter 220 to flexible tube 210 and prevents first suture “S₁” from loosening as it is clinched between the outer wall of the adapter 220 and inner wall of flexible tube 210. It is envisioned that more than one suture may be used to secure anvil head assembly 110 in a pre-fired tilted position. It is also envisioned that first suture “S₁” need not be passed through bore 221 but instead can clamped between adapter 220 and the inner wall of the flexible tube 210.

[0069] Turning back to FIG. 9, suture guide assembly 204 of anvil delivery system 200 includes a reel assembly 230. Reel assembly 230 is configured to house and facilitate manipulation of second suture “S₂”. Reel assembly 230 includes a housing 240 and a reel member 250.

[0070] With reference now to FIGS. 13 and 14, housing 240 of reel assembly 230 includes a substantially circular body 242 defining an annular cavity or recess 241. Circular body 242 may include a textured surface to facilitate operable engagement by a user, e.g. ribs 242a (FIG. 13). Housing 240 further includes a radially outward extending tab 244 and an annular flange 246. Tab 244 defines an opening 243 and a pair of slots 245. Opening 243 is configured to receive second suture “S₂” and operates to guide second suture “S₂” from reel member 250 (FIG. 15). Slots 245 are configured to selectively receive and secure second suture “S₂” once a sufficient length of second suture “S₂” is released from reel member 250.

[0071] Turning to FIGS. 15 and 16, reel member 250 of reel assembly 230 includes a substantially circular body 252 defining an annular recesses 251 extending about an outer perimeter 254 of circular body 252. Annular recess 253 is configured to receive second suture “S₂”. Circular body 252 further defines an opening 253 configured to operably receive annular flange 246 of housing 240 such that circular body 252 is rotatably supported within annular cavity 241 of a housing 240. Circular body 252 is rotatably supported within housing 240 to permit the release of second suture “S₂” from within annular recess 251 of reel member 250.

[0072] Referring to FIGS. 17-19, suture guide assembly 204 of anvil delivery system 200 is shown operably attached to anvil assembly 100. Although suture guide assembly 204 may be provided to a clinician pre-attached to anvil assembly 100, is envisioned that suture guide assembly 204 and anvil assembly 100 may be provided as separate components that can be attached to one another by a clinician prior to use. Second suture “S₂” is attached to anvil assembly 100 by threading an end of second suture “S₂” into a first opening of second openings 117b of anvil head 110, through slot 133 of cutting ring 130 and notch 116a of anvil head 110, and out a second opening of second openings 117b. First and second ends of second suture “S₂” are then threaded through opening 243 formed in tab 244 of housing 240 of reel assembly 230 and secured about reel member 250 of reel assembly 230. To secure second suture “S₂” to reel member 250, second suture “S₂” is wound in annular recess 251 about reel member 250. Reel member 250 is then secured to housing 240 by positioning reel member 250 within annular cavity 241 of housing 240 and positioning flange 246 of housing 240 within opening 253 of reel member 250.

[0073] With reference now to FIG. 20, a method for delivering anvil assembly 100 to a surgical site within a patient will be described. In one method, anvil assembly 100 is provided in the first tilted position supported on tubular guide member 202 of anvil delivery system 200 and suture guide assembly 204 is attached to anvil head 110 such that anvil assembly 100 is ready for delivery. Alternatively, the suture guide assembly 204 and tubular guide assembly 202 can be provided separately from anvil assembly 100 and a clinician can secure anvil assembly 100 to tubular guide assembly 202 and/or suture guide assembly 204 of anvil delivery system 200 as discussed above. In this manner, tubular guide assembly 202, suture guide assembly 204, and/or anvil assembly 100 may be provided to a clinician as separate components, or together as kit. Once flexible tube 210 of tubular guide assembly 202 has been secured to anvil assembly 100 and second suture “S₂” of suture guide assembly 204 has been attached to anvil assembly 100, the surgeon inserts closed end 210b of flexible tube 210 in the patient's mouth “M” and moves closed end 210b along with flexible tube 210 down through esophagus “E” to a surgical site, e.g., the stomach “St”. As anvil assembly 100 travels through esophagus “E” to the surgical site, second suture “S₂” is unwound from reel assembly 230 of suture guide assembly 204. Suture guide assembly 204 may be used at any point during insertion and prior to completion of the stapling procedure to retract anvil assembly 100 back through esophagus “E” and out of the patients mouth “M”. Suture guide assembly 204 may also be used to manipulate anvil assembly 100 in the event anvil assembly 100 becomes stuck and/or, is not properly positioned within the patient “P”.

[0074] After insertion, the surgeon then makes a first incision “I₁” at the surgical site (stomach “St” as shown) to provide access to closed end 210b of flexible tube 210. Thereafter, the surgeon pulls open end 52b of flexible tube 52 through first incision “I₁” to position the anvil assembly 100 at the surgical site. In some procedures it may be beneficial to pull flexible tube 210 through incision “I₁” until center rod assembly 104 of anvil assembly 100 advances through first incision “I₁”. When anvil assembly 100 is properly positioned at the surgical site, the surgeon releases tubular guide assembly 202 of anvil delivery system 200 from anvil assembly 100 by cutting suture “S₁” and separating anvil assembly 100 from second end 20b of adapter 220. Flexible tube 210 and adapter 220 may then be pulled from the body through first incision “I₁”. Second suture “S₂” of suture guide assembly 204 may also be secured within slots 245 formed in tab 244 of housing 240 of reel assembly 230.

[0075] In one method, a second incision “I₂” is then formed at the surgical site such that distal head portion 16 of stapling device 10 may be received therethrough. Alternatively, distal head portion 16 of stapling device 10 may be received through first incision “I₁” once tubular guide assembly 202 of anvil deliver system 200 has been removed therefrom.

[0076] Referring to FIGS. 21 and 22, after stapling device 10 and anvil assembly 100 are positioned at the surgical site, anvil assembly 100 can be secured to stapling device 10 by inserting retractable trocar 54 into bore 161 of center rod 160 of anvil assembly 100. Because the anvil retainer assembly 50 is unapproximated when anvil assembly 100 is attached and stapling device 10 (FIG. 1) has yet to be fired, trocar 54 is in its advanced position. When trocar 54, in its advanced position, is inserted into center rod throughbore 161, tip 54b of trocar 52 engages base portion 182 of second slide member 180 and moves second slide member 180 towards first slide member 170 to move anvil head 110 from its tilted position to its operative, non-tilted position via links 190, 192 with anvil head 110 in its operative position, tissue to anastomosed can be secured about anvil center rod 160 using known techniques.

[0077] Referring to FIGS. 23 and 24, when the anvil assembly 100 and shell assembly 30 are approximated, cam member 62 is prevented from pivoting by bushing 44 and arms 43 of pusher 40. Since cam member 62 is not free to pivot, finger 62a is positioned to prevent pin 58 from moving proximally within body portion 52 of anvil retainer assembly 50 to prevent retraction of trocar 54. As such, trocar tip 54b engages second slide member 180 to retain second slide member 180 in its advanced position. As such, anvil head 102 is retained in the operative, non-tilted position.

[0078] With reference now to FIG. 25, stapling device 10 (FIG. 1) may then be fired. During firing of stapling device 10, knife blade 38 mounted within shell assembly 30 on distal end portion 16 of stapling device 10 is advanced distally into engagement with head assembly 102 of anvil assembly 100. In some embodiments, knife blade 38 can be advanced subsequent to and/or independently of pusher 40. Distal advancement of knife blade 38 causes knife blade 38 to pass through cover 140 and into cutting ring 130 of anvil assembly 100. As knife blade 38 engages cutting ring 130, second suture “S₂” which is received within slot 133 of cutting ring 130 is severed. As such, second suture “S₂” and suture guide assembly 204 is disconnected from anvil assembly 100. As noted above, prior to firing of stapling device 10 (FIG. 1), suture guide assembly 204 may be used to facilitate position of anvil assembly 100 and/or to retract anvil assembly 100 back through the patient's mouth “M” (FIG. 20). By severing second suture “S₂”, second suture “S₂” does not need to be retracted through second openings 117b (FIG. 19) to detach second suture “S₂” from anvil assembly 100. This reduces the likelihood of any tissue damage caused by friction while retracting second suture “S₂” from head assembly 102. Further, by not having to retract second suture “S₂” through second openings 117b in head assembly 102 of anvil assembly 100, the likelihood of introducing bacteria or other foreign material into the patient is reduced.

[0079] Referring to FIGS. 26 and 27, when stapling device 10 (FIG. 1) is fired and pusher 40 is moved distally about bushing 44, arms 43 of pusher 40 are deformed outwardly away from cam member 62. Engagement between pin 58 and the angled face of finger 62a causes cam member 62 to pivot. When cam member 62 pivots, pin 58 moves proximally into recess 63 of cam member 62 and trocar 54 moves to its retracted position within longitudinal bore 53 of body portion 52 under the bias of spring 56. As trocar 54 moves to its retracted position, biasing member 196 urges first and second slide members 170, 180 apart to urge anvil head 110 to its tilted reduced profile position (see FIG. 28). Because of the proximity of anvil head 110 to shell assembly 30, anvil head 110 will only move to its tilted reduced profile position during unapproximation of anvil assembly 100 and shell assembly 30. Anvil assembly 100 may then be removed from the surgical site and the surgical procedure may be completed in a traditional manner.

[0080] In further embodiments, the suture can be attached to the anvil assembly at a location that is not near the knife or cut ring. In this way, the knife does not sever the suture. The procedure is carried out as discussed above, except that one leg only of the suture is cut and then the suture guide assembly and suture are removed. Then, the anvil assembly is attached to the instrument, attachment actuating the movement of the anvil away from the tilted position, and the instrument is fired. Firing initiates movement of the anvil from the operative position back to the tilted position.

[0081] It will be understood that various modifications may be made to the embodiments disclosed herein. For example, the slotted cutting ring may be incorporated into anvil assemblies having alternative configurations. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.