WO2025155666A1

WO2025155666A1 - Circular stapling instrument

Info

Publication number: WO2025155666A1
Application number: PCT/US2025/011788
Authority: WO
Inventors: Kristopher Yee; Samuel HOCHHEIMER
Original assignee: Intuitive Surgical Operations Inc
Current assignee: Intuitive Surgical Operations Inc
Priority date: 2024-01-16
Filing date: 2025-01-16
Publication date: 2025-07-24
Anticipated expiration: 2026-07-16

Abstract

A circular stapling instrument for joining tissue structures comprises a staple assembly comprising a plurality of staples and a cutting element and an anvil positioned distal to the staple assembly. The instrument further includes a driver configured to sequentially advance the staples and then the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly. Cutting of the tissue only begins after the staples have deformed against the anvil and joined the tissue structures together. This inhibits or prevents tissue displacement during staple formation, resulting in a more uniform thickness of stapled tissue and an improvement in cut quality, which reduces the risk of an anastomotic leak.

Description

CIRCULAR STAPLING INSTRUMENT

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial Nos. 63/621,476, 63/621,490 and 63/621,462, filed January 16, 2024, the complete disclosures of which are incorporated herein by reference for all purposes.

TECHNICAL FIELD

[0002] This description generally relates to endoscopic surgical instruments for dissecting, occluding and/or sealing tissue, and more particularly to endoscopic circular staplers that are particularly useful for joining tubular tissue structures together.

BACKGROUND

[0003] In certain types of surgical procedures, the use of surgical staples has become the preferred method of joining tissues and, therefore, specially configured surgical staplers have been developed for different applications. For example, intraluminal or circular staplers have been developed for use in joining two tubular structures together, such as surgical procedures involving the lower colon wherein two separated regions of the lower colon are joined together in an anastomosis after a target area has been resected.

[0004] Circular staplers typically comprise an elongate shaft, which has a proximal actuation mechanism and a distal stapling mechanism mounted on the shaft. The distal stapling mechanism typically includes a stapling cartridge that houses a plurality of staples arranged in a concentric circular array. An annular cutting knife is mounted concentrically with the staples within the cartridge or the end effector of the instrument so that it can move axially relative to the cartridge. A movable trocar shaft or capturing spike extends axially from the center of the instrument to detachably couple the anvil to the stapling mechanism. The anvil is configured to shape the end of the staple as the staple is driven into the anvil. The distance between the distal surface of the staple cartridge and the staple anvil is typically controlled by an adjustment mechanism mounted at the proximal end of the stapler shaft to control the axial movement of the capturing spike.

[0005] When performing a low^zer colon procedure using a circular stapler, the surgeon typically uses a conventional linear stapler with two rows of staples placed on either side of the affected intestinal lesion to be removed and stapled. The target area is cut at the same time as the adjacent ends are stapled. After removing the affected area, the surgeon typically inserts the anvil of the circular stapler into the proximal end of the lumen, proximal of the staple line. Thi s is done by inserting the anvil head into an entrance that has been cut into the proximal lumen by the surgeon. Sometimes an anvil can be placed transanally by placing the anvil head at the distal end of the stapler and inserting the instrument through the rectum. The proximal end of the intestine is then tied to the anvil shaft using a purse string suture or other conventional tying device and the proximal and distal ends of the intestine are tightened within the gap by closing the gap between the anvil and the cartridge. The circular stapler is then actuated to join the ends and form a tubular passage by driving and forming multiple annular rows of staples through both ends of the intestine. At the same time as the staples are driven and formed, a concentric circular knife blade is driven through the end of the intestinal tissue to cut the end adjacent to the inner row of staples.

[0006] Current circular stapler devices use a single mechanism to deploy the staples and the knife blade. Thus, the actuation of the staple forming mechanism and the advancement of the knife occur simultaneously, which causes the knife to deploy and sever tissue before the staples have been fully formed. Because the tissue is under high compression, displacement of tissue may occur during staple formation as the knife severs the tissue between the clamping zone of the staples and the center of the tissue that is preventing the tissue from migrating outward. In addition, the user may place inadvertent tension on the tissue resulting in further tissue displacement. In some cases, this may cause staple malformation, a reduction in cut quality and/or a reduction in the amount of tissue incorporated into the staple line, which are factors that could reduce the quality of the anastomosis.

SUMMARY

[0007] The following presents a simplified summary of the claimed subject matter in order to provide a basic understanding of some aspects of the claimed subject matter. This summary is not an extensive overview of the claimed subject matter. It is intended to neither identify key or critical elements of the claimed subject matter nor delineate the scope of the claimed subject matter. Its sole purpose is to present some concepts of the claimed subject matter in a simplified form as a prelude to the more detailed description that is presented later.

[0008] In one aspect, a circular stapling instrument comprises a staple assembly comprising a plurality of staples and a cutting element, and an anvil positioned distal to the staple assembly. The instrument further includes a driver configured to sequentially advance the staples and the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly. With this configuration, the staples are fully formed before the cutting element contacts the tissue. Thus, cutting of the tissue only begins after the staples have deformed against the anvil and joined the tissue structures together. This inhibits or prevents tissue displacement during staple formation, resulting in proper staple formation, a more uniform thickness of stapled tissue and an improvement in cut quality, which reduces the risk of an anastomotic leak.

[0009] In various embodiments, the instrument comprises a first pusher coupled to the staples and a second pusher coupled to the cutting element or knife. The first and second pushers cooperate with the driver to advance the staples and the cutting element distally towards the anvil.

[0010] In various embodiments, the staple pusher comprises a proximal cam surface and the driver comprises one or more distal protrusions or “followers” configured to contact the proximal cam surface such that rotation of the driver causes the follower(s) to move along the proximal cam surface. The proximal cam surface is inclined such that it extends at a transverse angle relative to a vertical plane that is substantially perpendicular to the longitudinal axis of the instrument. Rotation of the driver and the follower(s) translates the staple pusher in a longitudinal direction.

[0011] In various embodiments, the proximal cam surface of the staple pusher includes a first portion that is inclined as described above and a second portion that is substantially flat such that it is substantially parallel to the plane perpendicular to the longitudinal axis of the instrument. This second portion creates a “dead zone” wherein rotation of the driver no longer advances the staple pusher in the longitudinal direction.

[0012] In various embodiments, the knife pusher also includes a proximal cam surface and the driver includes one or more distal protrusions or followers configured to contact the proximal cam surface of the knife pusher such that rotation of the driver causes the distal protrusion to move along the proximal cam surface. The proximal cam surface is inclined such that it extends at a transverse angle relative to a vertical plane that is substantially perpendicular to the longitudinal axis of the instrument. Similar to the staple pusher, rotation of the driver and the distal protrusion translates the knife pusher in a longitudinal direction.

[0013] In various embodiments, the staple pusher comprises an internal channel and the proximal cam surface of the knife pusher extends through the internal channel proximally of the proximal cam surface of the staple pusher. The proximal cam surface of the knife pusher is substantially aligned with the second portion or “dead zone” of the proximal cam surface of the staple pusher. With this configuration, the follower simultaneously contacts the proximal cam surface of the knife pusher and the dead zone of the staple pusher cam surface such that the knife is advanced distally while the staple pusher remains in place.

[0014] In embodiments, the follower is initially aligned with the first portion of the staple pusher such that rotation of the driver causes the staple pusher to move distally while the knife remains in place. The staple pusher is advanced until the staples engage the anvil and fully form across the tissue structures. Once this occurs, the follower continues to rotate into the dead zone of the staple pusher and engages the cam surface of the knife pusher to advance the knife and sever the tissue.

[0015] In various embodiments, the first and second portions of the proximal cam surface of the staple pusher extend circumferentially about a longitudinal axis of the staple assembly. In an exemplary embodiment, the first and second portions of the proximal cam surface each extend about 90 to 270 degrees, or about 180 degrees, around the longitudinal axis.

[0016] In an alternative embodiment, the driver comprises first and second distal protrusions or followers circumferentially spaced from each other around the internal channel. In this embodiment, the staple pusher includes two inclined portions and two flat portions or dead zones. The first and second followers are initially aligned with the first and second inclined portions such that rotation of both followers causes distal advancement of the staple pusher. With this configuration, force is applied by the driver to opposite sides of the staple pusher to provide additional stability and an increased mechanical advantage or force applied to the staples as they form across the tissue structures.

[0017] In this embodiment, the knife pusher may comprise first and second cam surfaces aligned with the first and second dead zones of the staple pusher. The first and second followers are configured to engage the cam surfaces of the knife pusher to drive the knife into tissue. This provides additional stability to the knife and an increased force or mechanical advantage to the cutting operation.

[0018] In embodiments, the instrument further comprises a wrist assembly pivotally coupling the end effector with the elongate shaft. At least a portion of the driver is movable through the wrist assembly between the shaft and the end effector. In one such embodiment, the wrist assembly comprises one or more linkages for articulating the end effector around first and second axes, respectively. The first and second axes may be, for example, yaw and pitch axes.

[0019] In embodiments, the driver comprises a distal portion configured for engaging the staple and knife pushers and a flexible portion that extends through the wrist member when the distal portion is within the end effector. The drive member further comprises a proximal portion extending through the shaft and configured for coupling to an actuator, such as instrument handle or an external control system. The flexible portion allows the distal portion to articulate relative to the proximal portion when the end effector articulates about the wrist member.

[0020] In embodiments, the driver defines an internal channel and the instrument further comprising a capturing device or spike configured to advance through the internal channel to engage the anvil. The capturing device or spike is configured to move the anvil longitudinally relative to the staple assembly to approximate or un-approximate the anvil.

[0001] In embodiments, the staples are disposed circumferentially around an internal channel within the stapling assembly and the instrument further comprising an annular staple alignment guide disposed between the staples and the anvil. The staple alignment guide may comprise one or more slots or other guide features for aligning staples of a staple cartridge with the staple pusher such that distal movement of the staple pusher causes the staples to move distally to engage and deform against the tissue contacting surface of the anvil.

[0021] In embodiments, the stapling instrument further comprises an actuator coupled to a proximal end of the driver and configured to rotate the driver. The actuator may be configured for coupling to a robotic surgical system.

[0022] In embodiments, the anvil comprises a head and a shaft. The head comprises a tissue contacting surface comprising a plurality of staple forming pockets. The anvil head comprises first and second components movable relative to each other and configured for deploying between a collapsed configuration with a first diameter and an expanded configuration with a second diameter larger than the first diameter. The first and second components are configured, in the expanded configuration, to form a tissue contacting surface that resists the forces applied by the stapler instrument during the clamping and stapling operations. In addition, the staple pockets on the tissue contact surface are configured, in the expanded configuration, to align with the staples in the staple assembly such that the staples form properly within the pockets.

[0023] In embodiments, the anvil comprises a head and a shaft. The head comprises a plurality of petals each comprising a tissue contacting surface defining staple forming pockets. The petals are configured for deploying between a collapsed configuration with a first diameter and an expanded configuration with a second diameter, wherein the first diameter is smaller than the second diameter.

[0024] In embodiments, the anvil comprises a head and a shaft. The anvil head comprises an annular tissue contact surface comprising staple forming pockets. The instrument further comprises an expandable element coupled to the annular tissue contact surface and configured for deploying between a collapsed configuration with a first diameter and an expanded configuration with a second diameter larger than the first diameter.

[0025] In another aspect, a circular surgical stapling instrument for joining tissue comprises an elongate shaft and a stapling assembly coupled to a distal end of the shaft. The stapling assembly comprises a plurality of staples, a cutting element and a cam surface. The instrument further includes a driver comprising an engagement element for contacting the cam surface to advance the staples and the cutting element such that the staples contact the tissue before the cutting element is advanced distal of the staple assembly. In this embodiment, the driver is configured to advance the cutting element and the staples simultaneously such that the staples are fully formed before the knife contacts the tissue.

[0026] In various embodiments, the staple assembly comprises a first pusher coupled to the staples and a second pusher coupled to the cutting element. The engagement element of the driver comprises a rotatable element configured to contact the cam surface such that rotation of the driver causes longitudinal movement of the first and second pushers.

[0027] In one such embodiment, the cutting element is proximally recessed from the staples before the driver advances the first and second pushers. The driver must advance the knife pusher a greater distance than the staple pusher to contact tissue, ensuring that the staples are fully formed before the knife contacts the tissue.

[0028] In another such embodiment, the first pusher comprises a proximal cam surface and the second pusher comprises a proximal cam surface. The proximal cam surfaces of the first and second pushers each extend at a transverse angle to a vertical plane substantially perpendicular to a longitudinal axis of the staple assembly such that rotation of the driver translates the first and second pushers in a longitudinal direction. The angle of the staple pusher is greater than the angle of the knife pusher such that the driver advances the staples more rapidly than the cutting element, ensuring that the staples are fully formed before the knife contacts the tissue.

[0029] In another aspect, a method of joining tissue structures comprises positioning a staple assembly adjacent first and second tissue structures and advancing a plurality of staples into the first and second tissue structures to join the first tissue structure to the second tissue structure. The method further comprises advancing a cutting element through the first and second tissue structures after the tissue structures have been joined together.

[0030] In embodiments, the method further comprises rotating a driver to advance the plurality of staples and the cutting element such that the staples form against an anvil before the cutting element contacts the tissue. Rotation of the driver causes longitudinal movement of a staple pusher coupled to the staples and a knife pusher coupled to the cutting element.

[0031] In embodiments, the driver sequentially advances the staple pusher and the knife pusher. The driver is disengaged from the staple pusher after the staples have contacted the anvil. The driver remains engaged to the knife pusher to advance the knife against the tissue.

[0032] In various embodiments, the method includes rotating the driver to cause a distal protrusion or follower of the driver to engage an inclined proximal cam surface of the staple pusher and advance the staple pusher distally. The driver is further rotated to cause the follower to engage an inclined proximal cam surface of the knife pusher to advance the knife distally.

[0033] In an exemplary embodiment, the method comprises positioning an anvil within a target location within the first tissue structure and positioning the staple assembly within a target location with the second tissue structure. The two tissue structures may comprise tubular structures, such as two separate sections of an intestine. The method further comprises advancing the staple pusher to drive the staples the two tissue structures to join the first tissue structure to the second tissue structure and then advancing the knife pusher to sever the tissue structures adjacent a row of staples.

[0034] In another aspect, a circular stapling system comprises a surgical instrument and a delivery instrument. The surgical instrument comprises a staple assembly comprising a plurality of staples, a cutting element, a driver configured to sequentially advance the staples and the cutting element and an anvil movable between a collapsed configuration and an expanded configuration. The delivery instrument comprises an engagement mechanism for engaging the anvil and moving the anvil between the collapsed configuration and the expanded configuration.

[0035] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the description. Additional features will be set forth in part in the description which follows or may be learned by practice of the description. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and other aspects, features, and advantages of the present surgical instruments will become more apparent in light of the following detailed description when taken in conjunction with the accompanying drawings in which:

[0037] FIG. 1 is a perspective view of a distal end of a circular stapler;

[0038] FIG. 2 is a perspective view of a staple assembly for the circular stapler of

FIG. 1;

[0039] FIG. 3 is an exploded view of the staple assembly;

[0040] FIG. 4 is a proximal view of one portion of the staple assembly;

[0041] FIG. 5 illustrates the staple assembly in an initial position;

[0042] FIG. 6 illustrates the staple assembly in a second position;

[0043] FIG. 7 illustrates the staple assembly in a third position;

[0044] FIGS. 8 illustrates the staple assembly in a fourth position;

[0045] FIG. 9 illustrates the staple assembly in a final position;

[0046] FIG. 10 is an alternative embodiment of a driver for the staple assembly;

[0047] FIGS. 11A-11E schematically illustrate operation of the devices described herein for sealing and cutting tissue;

[0048] FIGS. 12A-12C illustrate one embodiment of a collapsible anvil for a circular stapler;

[0049] FIG. 13 illustrates another embodiment of a collapsible anvil for a circular stapler;

[0050] FIGS. 14A-14C illustrate the deployment of an anvil head of the anvil of FIG. 13;

[0051] FIGS. 15A and 15B illustrates another embodiment of an anvil for a circular stapler;

[0052] FIG. 16A illustrates another embodiment of an anvil for a circular stapler in an expanded configuration;

[0053] FIG. 16B illustrates the anvil of FIG. 16A in an expanded configuration;

[0054] FIGS. 17A and 17B illustrate another embodiment of a collapsible anvil for a circular stapler;

[0055] FIGS. 18A-18C illustrate deployment of the anvil of FIGS. 17A and 17B; [0056] FIGS. 19A and 19B illustrate another embodiment of a collapsible anvil for a circular stapler;

[0057] FIGS. 20A-20C illustrate another embodiment of a collapsible anvil for a circular stapler;

[0058] FIGS. 21 A and 21B illustrate another embodiment of a collapsible anvil for a circular stapler;

[0059] FIGS. 22A-22C illustrates deployment of the anvil of FIGS 21A and 21B;

[0060] FIG. 23 is a perspective view of the distal end portion of a delivery instrument for the anvil;

[0061] FIG. 24 illustrates the delivery instrument with closed jaws for advancing the anvil to a target region within a patient;

[0062] FIG. 25 illustrates the delivery instrument after expanding the anvil at the target region;

[0063] FIG. 26 illustrates the delivery instrument manipulating a shaft of an anvil of a circular stapler;

[0064] FIG. 27 illustrates the jaws of the delivery instrument grasping the anvil shaft;

[0065] FIG. 28 is a perspective view of a representative teleoperated surgical instrument;

[0066] FIG. 29 illustrates a top view of an operating room employing a robotic surgical system; and

[0067] FIG. 30 illustrates a simplified side view of a robotic arm assembly.

DETAILED DESCRIPTION

[0068] Particular embodiments of the present surgical instruments are described hereinbelow with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are merely exemplary and may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the devices herein in virtually any appropriately detailed structure. Well-known functions or constructions are not described in detail to avoid obscuring the present description in any unnecessary detail. Like numbers in two or more figures represent the same or similar elements, furthermore, elements and their associated aspects that are described in detail with reference to one embodiment may, whenever practical, be included in other embodiments in which they are not specifically shown or described. For example, if an element is described in detail with reference to one embodiment and is not described with reference to a second embodiment, the element may nevertheless be claimed as included in the second embodiment. Moreover, the depictions herein are for illustrative purposes only and do not necessarily reflect the actual shape, size, or dimensions of the system or illustrated components.

[0069] While the following is presented with respect to circular stapling instruments, it should be understood that certain features of the presently described surgical instruments may be readily adapted for use in any type of surgical clamping, cutting, ligating, dissecting, clipping, cauterizing, suturing and/or sealing instrument, whether or not the surgical instrument applies a clip or other type of fastener. Additionally, the features of the presently described circular stapling instruments may be readily adapted for use in surgical instruments that are actuated using any technique within the purview of those skilled in the art, such as, for example, manually activated surgical instruments, powered surgical instruments (e.g., electro-mechanically powered instruments), robotic surgical instruments, and the like.

[0070] The devices described herein, or certain components of the devices, may also be incorporated into a variety of different surgical instruments, such as those described in commonly assigned, co-pending US. Patent Application Nos. 16/205,128, 16/427,427, 16/678,405, 16/904,482, 17/081,088 and 17/084,981 and International Patent Nos. PCT/US2019/107646, PCT/US2019/019501, PCT/US2019/062344, PCT/US2020/54568, PCT/US2019/064861, PCT/US2019/062768, PCT/2020/025655, PCT/US2020/056979,

PCT/2019/066513, PCT/US2020/020672, PCT/US2019/066530 and PCT/US2020/033481, the complete disclosures of which are incorporated by reference herein in their entirety for all purposes as if copied and pasted herein.

[0071] Fig. 1 illustrates a distal portion of a surgical circular stapling instrument 100 in accordance with an illustrative embodiment. Surgical instrument 100 includes an end effector 110, an elongated shaft 105 and, in some embodiments, a wrist assembly (not shown) coupling end effector 110 to shaft 105. End effector 110 generally comprises a circular stapling assembly 120, an anvil 130 and a capturing device 140 (see FIG. 2) for advancing and retracting anvil 130 relative to stapling assembly 120, as discussed in more detail below. The proximal end portion of elongate shaft 105 is operatively connected to an actuation mechanism (not shown), although as those skilled in the art reading this description will appreciate, components of the actuation mechanism may extend into, and/or pass through elongated shaft 105 and/or the wrist assembly.

[0072] In various embodiments, instrument 100 will include a proximal handle (not shown) for actuating the end effector 110 and, in some embodiments, for controlling the orientation and movement of end effector 110. In other embodiments, instrument 100 is adapted to be used with a robotic system. In these embodiments, instrument 100 will generally include an actuation mechanism that controls the orientation and movement of the end effector. The actuation mechanism will typically be controlled by a robotic manipulator assembly that is controlled remotely by a user. For example, in one configuration, the actuation mechanism will be manipulated by the robotic manipulator assembly to move capturing device 140 towards and away from stapling assembly 120 and/or to deploy staples and a cutting element, such as a knife (discussed in more detail below).

[0073] The actuation mechanism may include input couplers (not shown) instead of, or in addition to, the stationary and movable handles. In certain embodiments, surgical instrument 100 will further include a backend mechanism or proximal housing 510 (see FIG. 12) coupled to the proximal end portion of elongate shaft 105. The backend mechanism typically provides a mechanical coupling between the drive tendons, rods or cables of the instrument and motorized axes of the mechanical interface of a drive system. Further details of known backend mechanisms and surgical systems are described, for example, in U.S. Pat. No. 8,597,280, U.S. Pat. No. 7,048,745, and U.S. Pat No. 10,016,244. Each of these patents is hereby incorporated by reference in its entirety.

[0074] The input couplers may interface with, and be driven by, corresponding output couplers (not shown) of a telesurgical surgery system, such as the system disclosed in U.S Pub. No. 2014/0183244A1, the entire disclosure of which is incorporated by reference herein. The input couplers are drivingly coupled with one or more input members (not shown) that are disposed within the instrument shaft 105. The input members are drivingly coupled with the end effector 110. Suitable input couplers can be adapted to mate with various types of motor packs (not shown), such as the stapler-specific motor packs disclosed in U.S. Pat. No. 8,912,746, or the universal motor packs disclosed in U.S. Pat. No. 8,529,582, the disclosures of both of which are incorporated by reference herein in their entirety. Further details of known input couplers and surgical systems are described, for example, in U.S. Pat. No. 8,597,280, U.S. Pat. No. 7,048,745, and U.S. Pat No. 10,016,244. Each of these patents is hereby incorporated by reference in its entirety for all purposes.

[0075] While described herein with respect to an instrument configured for use with a robotic surgical system, it should be understood that the actuation and drive assemblies described herein may be incorporated into manually actuated instruments, electro-mechanical powered instruments, or instruments actuated in any other way. For example, the actuation mechanism may comprise a handle assembly for gripping by the user that includes a stationary handle and a moveable handle, which serves as an actuator for surgical instrument 100.

[0076] Referring now to FIGS. 2 and 3, stapling assembly 120 comprises a housing 150 having a substantially cylindrical main body 152 with an internal channel 154 for receiving a cutting element assembly 160, a staple pusher 170 and a staple cartridge 180. Housing 150 couples the stapling assembly 120 to shaft 105. In some embodiments, housing 150 may comprise an inclined surface 153 that tapers inwardly in the proximal direction to accommodate a stapling assembly 120 having a larger diameter than shaft 105.

[0077] Stapling assembly 120 may be removably coupled to shaft 105, or permanently affixed thereto. In certain embodiments, stapling assembly 120 is a disposable component of instrument 120 and may be removably attached to shaft 105. In other embodiments, staple cartridge 180 is a disposable component of instrument and may be removably coupled to staple assembly 120. In other embodiments, the entire instrument 120 is manufactured together and may be either a disposable or reusable instrument.

[0078] As shown in FIG. 1, anvil 130 includes an anvil head 132 and an anvil shaft 134. Anvil shaft 134 is insertable into internal channel 154 of housing 150 and is removably and slidably securable therein. Capturing device 140 is configured to advance and withdraw through channel 154 to translate anvil 130 along a longitudinal axis relative to staple assembly 120 to approximate or un-approximate anvil 130 relative to staple assembly 120. Anvil head 132 includes a tissue contacting surface 136 defining staple forming pockets (not shown) for receiving staples 200, as discussed below in reference to FIGS. 11 A-l ID.

[0079] As shown in FIG. 3, staple pusher 170 defines a substantially cylindrical shape and is coaxially and slidably disposed within internal channel 154 of housing 150. Staple pusher 170 includes a main body 174 and at least one annular array of staple engagement members or fingers 176 extending from the distal end of body 174. Each finger 176 is configured to be received within a slot of staple cartridge 180 to engage staples 200. Staple pusher 170 is configured to advance relative to housing 150 to engage, drive and eject staples 200 against the staple forming pockets of anvil 130. As shown in FIG 2., fingers 176 of staple pusher 170 are recessed proximally from the distal end of housing 150 to provide room for staple cartridge 180.

[0080] Staple cartridge 180 may include one, two or more than two annular arrays or rows of fingers with staple receiving slots (not shown) for receiving one or more sets of concentric staple arrays 200. Staple cartridge 180 is removably or permanently coupled to staple pusher 170 such that staple pusher 170 may drive staples 200 from cartridge 180 into tissue (discussed in more detail below). In particular, distal fingers 175 of staple pusher 170 are configured to advance into the slots of cartridge 180 to drive staples 200 distally.

[0081] In certain embodiments, staple cartridge 180 comprises an annular main body 182 with circumferential slots (not shown) that extend between the distal end of an array of distal fingers 176 on staple pusher 170 and the inner surface of housing 150. The circumferential slots function to align staples 200 with fingers 176 of staple pusher 170 such that distal movement of staple pusher 170 causes staples 200 to move distally to engage and deform against tissue contacting surface 136 of anvil 130.

[0082] Referring now to FIG. 4, staple pusher 170 comprises a proximal cam surface 210 for engagement with a driver 190, which is discussed in more detail below. Cam surface 210 has a generally annular shape and extends around a central channel 212 within staple pusher 170 that extends substantially parallel to a longitudinal axis 214 of staple pusher 170 and stapling assembly 120. Cam surface 210 includes a first portion 220 that has an inclined surface, preferably having an angle transverse to a plane that is substantially perpendicular to longitudinal axis 214 (see FIG. 5). Thus, as first portion 220 of cam surface 210 extends in the clockwise direction, it also extends proximally (i.e., in the direction towards shaft 105) such that an upper section 222 of first portion 220 is disposed proximal to a lower section 224 of first portion 202. Of course, it will be recognized that the terms “upper” and “lower” are only used herein in reference to the orientation shown in FIG. 4. Sections 222, 224 may be in any orientation relative to each other depending on the overall orientation of instrument 100. Cam surface 210 includes a second portion 230 or “dead zone” (discussed below) that is substantially flat such that it extends generally parallel to the plane that is substantially perpendicular to longitudinal axis 214.

[0083] Cutting element assembly 160 generally comprises an annular pusher 164 and an annular cutting element or knife 166 at the distal end of pusher 164. In some embodiments, knife 166 is a sharpened distal extension of pusher 164. Pusher 164 is configured to advance relative to housing 150 to drive knife 166 through tissue disposed between anvil 130 and stapling assembly 120.

[0084] As shown in FIGS. 4 and 5, knife pusher 164 has a proximal cam surface 240 extending laterally inside of, and proximal to, cam surface 210 of staple pusher 170. As shown, cam surface 240 has an inclined surface having an angle transverse to the plane that is substantially perpendicular to longitudinal axis 214. Thus, as cam surface 240 extends in the clockwise direction, it extends proximally (i.e., in a direction towards shaft 105) such that a lower section 242 of surface 240 is disposed proximal to an upper section 224 of surface 220. Again, it will be recognized that the terms “upper” and “lower” are only used herein in reference to the orientation shown in FIG. 4. Cam surface 240 of knife pusher 164 is circumferentially aligned with the second portion 230 or dead zone of staple pusher cam surface 210 for reasons discussed below.

[0085] Instrument 100 further includes a driver 190 for advancing cutting element assembly 160 and staple pusher 170 towards anvil 130. Driver 190 comprises an internal lumen 198 extending therethrough. Capturing device 140 is configured for advancement through internal lumen 198 to engage and translate anvil 130 towards and away from stapling assembly 120. Driver 190 has a proximal end suitably coupled to an actuation mechanism (not shown) for rotating driver 190 relative to end effector 110. In some embodiments, instrument 100 comprises a wrist assembly (not shown) pivotally coupling end effector 110 with shaft 105. At least a portion of driver 190 is movable through the wrist assembly between shaft 105 and end effector 110. In one such embodiment, the wrist assembly comprises one or more linkages for articulating the end effector around first and second axes, respectively. The first and second axes may be, for example, yaw and pitch axes.

[0086] In embodiments, driver 190 comprises the distal portion described above for engaging the staple and knife pushers and a flexible portion (not shown) that extends through the wrist member when the distal portion is within end effector 110. The flexible portion allows the distal portion to articulate relative to the proximal portion when end effector 110 articulates about the wrist member. The drive member further comprises a proximal portion (not shown) extending through the shaft and configured for coupling to an actuator, such as instrument handle or an external control system. In various embodiments, the flexible portion of driver 190 comprises a bendable laser cut hypo tube that extends through shaft 105 of instrument 100. The hypo tube has sufficiently flexibility to bend as the end effector 110 is rotated relative to shaft 105. [0087] As shown in FIG. 3, driver 190 comprises an annular body 250 having a distal surface 252 with at least one protrusion or follower 254 extending distally therefrom. Follower 254 is configured to contact cam surfaces 210, 240 of staple pusher 170 and knife pusher 164 and to ride along these cam surfaces 210, 240 as driver 190 rotates to translate this rotational movement into distal movement of staple pusher 170 and knife pusher 164. In one embodiment, driver 190 is rotatable such that follower 254 rotates therewith. In another embodiment, driver 190 comprises a mechanism for rotating follower 254 relative to body 250 such that the main body of driver 190 does not rotate, but follower 254 rotates around distal surface 252.

[0088] Referring now to FIG. 5, driver 190 starts in an initial position wherein follower 254 engages first portion 220 of staple pusher cam surface 210 near the lower section 224 of surface 210. As driver 190 rotates in the clockwise direction, follower 254 rides along first portion 220 of cam surface 210. Since this surface is inclined, this rotation causes staple pusher 170 to advance distally (i.e., in a direction away from shaft 105). Note that at this stage, follower 254 does not contact cam surface 240 of knife pusher 164 and, therefore, the knife 166 is not advanced distally.

[0089] Referring now to FIGS. 6 and 7, as follower 254 rides towards upper portion 222 of cam surface 210, staple pusher 170 continues to advance distally. Once follower 254 reaches second portion 230 or the dead zone of cam surface 210, it no longer advances staple pusher 170 because this portion 230 of cam surface 210 is substantially parallel to the plane perpendicular to longitudinal axis 214. At this point, the staples 200 have been driven against the anvil 130 and have fully formed through the tissue between anvil 130 and stapler assembly 120. Note that at this stage, follower 254 does not contact cam surface 240 of knife pusher 164 and, therefore, the knife 166 is not advanced distally. Thus, staples 200 are driven into the tissue and against tissue contacting surface 136 of anvil 130 before knife 166 extends distally of housing 150.

[0090] Referring now to FIGS. 7-9, as follower 254 continues to rotate in the clockwise direction, it contacts proximal cam surface 240 of knife pusher 164. Again, since this surface is inclined at an angle relative to the plane perpendicular to longitudinal axis 214, this rotation advances knife pusher 164 and knife 166 in the distal direction until knife 166 extends beyond the distal end of housing 150 and severs the tissue.

[0091] Applicant notes that in the embodiment shown in FIGS. 2-9, driver 190 includes only one protrusion or follower 254 that rides along the cam surfaces 210, 240 of staple pusher 170 and knife pusher 160 about 360 degrees in order to completely deploy both the staples 200 and the knife 166. However, it should be understood that other embodiments are contemplated. For example, first and/or second portions 220, 230 of the staple pusher cam surface 210 may extend less than 180 degrees around central channel 212. Alternatively, one of these portions may extend more than 180 degrees around central channel 212. For example, first portion 220 may extend between about 90 degrees to about 270 degrees and second portion 230 may extend between about 90 degrees to about 270 degrees.

[0092] In certain alternative embodiments, driver 190 is configured to advance knife pusher 160 and staple pusher 160 simultaneously such that staples 200 are fully formed prior to the knife 166 contacting the tissue. In one such embodiment, proximal cam surface 240 of knife pusher 160 may be aligned with first portion 220 of staple pusher cam surface 210 such that follower 254 contacts both of these surfaces simultaneously. However, knife 166 is proximally recessed from the distal end of staple pusher 160 such that driver 190 must advance knife pusher 164 a greater distance than staple pusher 160 in order for the respective knife and staples to contact tissue. Thus, staple pusher 160 is advanced distal of staple assembly 120 before knife 166. In this embodiment, proximal cam surface 240 of knife pusher 160 may be aligned with both inclined cam surface 220 and flat or dead zone cam surface 230 of stapler pusher 160 such that rotation of driver 190 initially causes both staple pusher 170 and knife pusher 160 to move distally, and then the staple pusher 170 stops moving distally as knife pusher 160 continues to drive knife 166 into tissue.

[0093] In another such embodiment, the angle of staple pusher cam surface 210 is greater than the angle of knife pusher cam surface 240. In this embodiment, driver 190 advances staple pusher 170 more rapidly than knife pusher 170 such that the staples are fully formed before the knife contacts the tissue. Similar to the above embodiment, proximal cam surface 240 of knife pusher 160 may be aligned with both inclined cam surface 220 and flat or dead zone cam surface 230 of stapler pusher 160 such that rotation of driver 190 initially causes both staple pusher 170 and knife pusher 160 to move distally, and then the staple pusher 170 stops moving distally as knife pusher 160 continues to drive knife 166 into tissue.

[0094] In another alternative embodiment, driver 190 includes more than one follower 254 extending from distal surface 252. In this embodiment, for example, driver 190 may include two, three, four or more followers that ride along cam surfaces 210, 240 of staple pusher 170 and/or knife pusher 164 to provide additional stability and/or mechanical advantage to the instrument. [0095] Referring now to FIG. 10, an alternative embodiment of a driver 290 comprises an annular body 261 having a distal surface 260 with first and second distal protrusions or followers 254, 255 extending therefrom. As shown, followers 254, 255 are spaced circumferentially about 180 degrees from each other around the annular body 261, although it should be recognized that other configurations are contemplated (i.e., followers 254, 255 may be spaced from each other about 90 to about 270 degrees around annular body 261, or driver 290 may comprises more than two followers). In this embodiment, cam surface 210 of staple pusher 170 may include four separate sections (two for each of the followers 254, 255). The first and second portions would be similar to the first and second portions 220, 230 described above, except that each would extend about 90 degrees around central channel 212. The third and fourth portions (not shown) would be similar to the first and second portions except that each would extend 90 degrees around central channel 212 on the opposite side of central channel 212 from the first and second portions. Thus, each follower 254, 255 would first ride along an inclined portion of the cam surface (simultaneously) to advance staple pusher forward and then along a non-inclined or a flat surface that is substantially perpendicular to the longitudinal axis (i.e., the dead zone wherein the staple pusher is not advanced distally).

[0096] In this embodiment, knife pusher 164 may include one or two cam surfaces extending proximally of the staple pusher cam surface 210 and circumferentially aligned with the flat portion(s) 230 of cam surface 210 of staple pusher 270. Similar to the above embodiment, once the followers 254, 255 reach the knife pusher cam surfaces, the staples are fully driven and formed into the tissue.

[0097] Referring now to FIGS. 11 A -1 ID, instrument 100 is particularly useful for joining two tubular structures in a patient, such as arteries, veins, and/or intestinal tissue 302. For example, in a lower coion procedure, the surgeon typically uses a conventional linear stapler with two rows of staples placed on either side of the affected intestinal lesion to be removed and stapled. The target area is cut at the same time as the adjacent ends are stapled. After removing the affected area, the surgeon typically inserts anvil 130 of instrument 100 into the proximal end of the lumen, proximal of the staple line. This is done by inserting anvil head 132 into an entrance that has been cut into the proximal lumen by the surgeon. In some embodiments, anvil 130 is placed transanally by placing anvil head 132 at the distal end of instrument 100 and inserting instrument 100 through the rectum. The proximal end of the intestine is then tied to anvil shaft 134 using a suture or other conventional tying device and die proximal and distal ends of the intestine are tightened within the gap by closing the gap between anvil 130 and staple cartridge 180

[0098] As shown in FIG. 11 A, anvil 130 is positioned within a first section 304 of separated intestinal tissue 302 and housing 150 is positioned with a second section 306 of the intestinal tissue. As shown in FIGS. 1 IB and 11C, staple pusher 170 is advanced distally such that staples 200 pass through first and second sections 304, 306 and deform against anvil 130 to join and seal the tissue sections 304, 306. At this point, tissue sections 304, 306 are stable and generally do not move relative to each other or instrument 100. As shown in FIG. 1 ID, knife 166 is then advanced distally to sever tissue structures 304, 306 inwardly from staples 200 to complete the anastomosis.

[0099] Referring now to FIGS. 12A-12C, another embodiment of an anvil 1130 for a circular stapler includes an anvil head 1132 and an anvil shaft 1134. Anvil shaft 1134 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. The capturing device (not shown) is configured to advance and withdraw through this internal channel to translate anvil 1130 along a longitudinal axis relative to staple assembly 120 to approximate or un-approximate anvil 1130 relative to staple assembly 120.

[00100] In this embodiment, anvil head 1132 comprises a central component 1140 and first and second lateral components 1142, 1144. In one embodiment, central component 1140 forms the central portion of a generally circular head 1132 and lateral components 1142, 1144 each comprise a semi-circular outer portion of the circular head 1132. In an exemplary embodiment, lateral components 1142, 1144 generally have the same size and shape, although it will be understood that one of the lateral components may be larger than the other.

[00101] As shown in FIG. 12B, central component 1140 is pivotally coupled to shaft 1134 such that it is movable from a collapsed configuration, wherein central component 1140 extends in a direction transverse, or substantially parallel to. shaft 1134 (FIG. 12B), to an expanded configuration, wherein central component 1140 extends in a direction traverse to, or substantially perpendicular to. shaft 1134 (FIG. 12C). In addition, first and second lateral components 1142, 1144 are pivotally coupled to central component 1140 such that they are movable between a collapsed configuration (FIG. 12B), wherein they are folded together towards central component 1140 and extend substantially perpendicular to central component 1140, to an expanded configuration, wherein lateral components 1142, 1144 extends substantially parallel to central component 140 to form an anvil suitable for cooperation with staple assembly 120 (FIG. 12C).

[00102] Anvil 1130 is configured such that it has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1134) in the collapsed configuration than in the expanded configuration. Lateral dimension is herein defined as the radial distance from the longitudinal axis of shaft to the furthest radial surface or point of the anvil 1130 from the longitudinal axis. In certain embodiments, anvil 1130 has a lateral dimension (or diameter in certain embodiments) of less than about 14 mm in the collapsed configuration such that anvil 1130 may be advanced through a cannula or other percutaneous entry point in the patient. Anvil 1130 may have a lateral dimension (or diameter) of at least about 20 mm or at least about 25 mm, or about 21 to about 33 mm in the expanded configuration, although it will be recognized that the dimensions of anvil 1130 may vary depending on the surgical procedure and the size of the percutaneous entry point into the patient.

[00103] Anvil head 1132 is configured such that when central portion 1140 and lateral portions 1142, 1144 are in the expanded configuration, they form a substantially circular disc. The disc has sufficient rigidity to withstand the forces of clamping and/or driving staples through the tissue against the staple pockets on the proximal surface of head 1132. In addition, the staples pockets are aligned with the circumferential staples that are driven against these pockets by staple assembly 120.

[00104] Anvil 1130 may further include one or more driver(s) (not shown) within shaft 1134 that have a distal end portion coupled to the pivot joints between shaft 1134 and central component 1140 and/or the pivot joints between lateral components 1142, 1144 and central component 1140 for pivoting or rotating these components relative to each other. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The driver(s) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00105] Referring now to FIGS. 13 and 14A-14C, another embodiment of an anvil 1200 includes an anvil head 1202 and an anvil shaft 1204. Anvil shaft 1204 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. The capturing device (not shown) is configured to advance and withdraw through this internal channel to translate anvil 1200 along a longitudinal axis relative to staple assembly 120 to approximate or un-approximate anvil 1200 relative to staple assembly 120. Anvil head 1202 is movable between a collapsed or substantially linear configuration (see FIGS. 13 and 14C) and an expanded or circular disc-shaped configuration (see FIG. 14A). Head 1202 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1204) in the linear configuration than in the circular configuration.

[00106] Anvil head 1202 comprises one or more linkages that are movable between the linear and circular configurations. In one embodiment, head 1202 comprises first, second and third linkages 1206, 1208, 1210. Each linkage comprises an outer surface 1217 and an inner surface 1218 that form at least a partial sector of a circle (or a sector of a circle having a hollow central area). All of the linkages are designed to pivot towards each other such that the linkages form a circular disc 1240 (see FIG. 14A). Each linkage 1206, 1208, 2110 further comprises a tissue contacting surface defining staple forming pockets (not shown) for receiving staples 1200 (see FIGS. 11 A-l ID discussed above).

[00107] In an exemplary embodiment, each linkage 1206, 1208, 1210 is substantially the same shape (i.e., sector) and thus forms one-third of the circular disc 1240 (see FIG. 14A), although it will be recognized that each linkage may have different shapes. In addition, it will be recognized that anvil head 1202 may comprise 2 linkages or 4 or more linkages. In addition, it should be recognized that certain of the linkages may be larger than the other linkages. For example, linkage 1206 may be semicircular, i.e., forming one-half of the disc 1240, while the remaining half is formed of 2 or more linkages. The staple forming pockets are circumferentially arranged on each linkage such that they align with staple bays in staple assembly 120 when the linkages are formed into disc 1240.

[00108] First linkage 1206 includes a pin 1224 pivotally coupled to a universal joint or disc 1212 on a distal end portion 1240 of anvil shaft 1204. Second linkage 1208 is pivotally coupled to first and third linkages 1206, 1210 with connecting pins 1214, 1216, respectively. Each linkage 1206, 1208, 1210 has a distance or radius between inner and outer surfaces 1217, 1218 that may be less than the overall radius of the circular disc when the linkages have formed together. Thus, as shown in FIG. 14 A, the linkages form a central opening 1232 in the expanded configuration. This configuration reduces the overall size of the linkages, which facilitates the deployment process.

[00109] In one embodiment, disc 1212 of anvil shaft 1204 is a universal joint configured to transmit rotary power from shaft 1204 or an actuator within shaft 1204. Disc 1212 is rotatably coupled to distal end portion 1240 of shaft 1204 at pin 1222. Disc 1212 may be rotatable relative to shaft 1204 such that, for example, counterclockwise (or clockwise) rotation of disc 1212 causes linkage 1206 to rotate in a clockwise (or counterclockwise) direction. This rotation further causes linkage 1208 to rotate in a clockwise direction which, in turn causes linkage 1210 to rotate in the same direction until the side surfaces of each linkage contact each other to form the circular disc 1240 (see FIGS. 14A-14C).

[00110] Disc 1212 is also configured to pivot between a first configuration, wherein disc 1212 is substantially parallel to shaft 1204, and a second configuration, wherein disc 1212 is transverse to shaft 1204, or preferably perpendicular to shaft 1204. Disc 1212 is coupled to first linkage 1206 such that this rotation, in turn, rotates circular disc 1240 until it is substantially perpendicular to anvil shaft 1204 and presents the tissue contacting surface in the proximal direction for receiving staples from staple assembly 120.

[00111] In use, disc 1212 and that attached linkages 1206, 1208, 1210 first rotate about pin 1222 until they are substantially perpendicular to shaft 1204. Then, linkages 1206, 1208, 1210 sequentially rotate about their connecting pins 1224, 1214 and 1216 until they each contact disc 1212 to form the overall circular disc 1240.

[00112] Anvil 1200 may further include one or more driver(s) (not shown) within shaft 1204 that has a distal end portion coupled to joint 1212 for rotating and/or pivoting joint 1212. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The driver(s) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00113] Referring now to FIGS. 15A and 15B, another embodiment of an anvil 1300 includes an anvil head 1304 and an anvil shaft 1302. As in previous embodiments, anvil shaft 1302 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1304 comprises one or more linkages 1306, 1308 that are movable between linear and circular configurations. Each linkage comprises an outer surface 1316 and an inner surface 1318 that form a sector of a circle. All of the linkages are designed to pivot towards each other such that the linkages form a circular disc (similar to disc 1240 in FIG. 14A). Each linkage further comprises a tissue contacting surface defining staple forming pockets (not shown) for receiving staples 200.

[00114] In an exemplary embodiment, anvil head 1302 comprises four linkages that are substantially the same shape (i.e., a partial sector of a circle) and thus form one-fourth of the circular disc, although it will be recognized that each linkage may have different shapes. In addition, it will be recognized that anvil head 1302 may comprise 2, linkages, 3 linkages or 5 or more linkages. For example, FIG. 15B illustrates an embodiment with 2 linkages 1306, 1308 that each comprise a semicircle. In addition, it should be recognized that certain of the linkages may be larger than the other linkages. For example, linkage 1306 may be a semicircular, forming one- half of the discs, while the remaining half is formed of 2 or more linkages.

[00115] Linkages 1306, 1308 are pivotally coupled to each other at a joint 1340, 1342 on their side surfaces. The proximal linkage 1306 is also pivotally coupled to a bar or rod 1320 at a joint 1330. Bar 1320 is, in turn, pivotally coupled to a head 1322 of a distal end portion 1326 of shaft 1302 by a joint 1332. Distal end portion 1326 is, in turn, is pivotally coupled to the remainder of shaft 1302 by a hinge or pin 1324 that extends through a channel (not shown) in shaft 1302 such that distal end portion 1326 may pivot between a substantially parallel orientation relative to shaft 1304 (see FIG. 15A) to a substantially perpendicular orientation (see FIG. 15B).

[00116] In use, distal end portion 1326 rotates about pin 1332 into a substantially perpendicular orientation relative to shaft 1302 (see FIG. 15B). Then, the various linkages 1306, 1308 rotate about head 1322 until they form the circular disc that presents the tissue contacting surface in the proximal direction for receiving staples from staple assembly 120.

[00117] Anvil 1300 may further include one or more driver(s) (not shown) within shaft 1304 that has a distal end portion coupled to head 1322 for rotating and/or pivoting head 1322. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The driver(s) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00118] Referring now to FIGS. 16A and 16B, another embodiment of an anvil 1350 includes an anvil head 1352 and an anvil shaft 1354. Similar to previous embodiments, anvil shaft 1354 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1352 is movable between a collapsed or stacked configuration (FIG. 16A) and an expanded or circular disc-shaped configuration (FIG. 16B). Head 1352 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1354) in the stacked configuration than in the circular configuration.

[00119] In this embodiment, anvil head 1352 comprises one or more linkages that are movable between “stacked” and “unstacked” configurations. In one embodiment, head 1352 comprises first, second, third and fourth linkages 1356, 1358, 1360, 1362. Each linkage comprises an outer surface and an inner surface that form a sector of a circle. All of the linkages are designed to move from a stacked configuration (FIG. 16 A) to an unstacked configuration such that the linkages form a circular disc (see FIG. 16B). The linkages are substantially aligned with the longitudinal axis of shaft 1354 in the stacked configuration. Anvil 1350 may further include one or more driver(s) (not shown) within shaft 1354 having a distal end portion coupled to a joint or linkage at the distal end of shaft 1354 for rotating and/or pivoting linkages 1356, 1358, 1360, 1362. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The driver(s) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00120] As shown in FIG. 16B, in the stacked configuration, each linkage comprises proximal and distal surfaces 1382, 1380. The proximal surfaces 1382 contain staple pockets (not shown) for receiving staples from staple assembly 120. In this configuration, the proximal surface 1382 of linkage 1356 faces anvil shaft 1354 and may be in contact with shaft 1354. The proximal surface 1382 of linkage 1358 faces the distal surface 1380 of linkage 1360 and may be in contact with this surface (and so on for each linkage in the stack).

[00121] Each linkage 1356, 1358, 1360, 1362 has a distance or radius between their inner and outer surfaces that may be less than the overall radius of the circular disc when the linkages have formed together. Thus, as shown in FIG. 16B, the linkages form a central opening 1370 in the expanded configuration. This configuration reduces the overall size of the linkages, which facilitates the deployment process.

[00122] In an exemplary embodiment, linkages 1356, 1358, 1360, 1362 are substantially the same shape (i.e., sector) and thus form one-fourth of the circular disc, although it will be recognized that each linkage may have different shapes. In addition, it will be recognized that anvil head 1352 may comprise 2 or 3 linkages or 5 or more linkages. In addition, it should be recognized that certain of the linkages may be larger than the other linkages. For example, linkage 356 may be a semicircular, forming one-half of the discs, while the remaining half is formed of 2 or more linkages.

[00123] Referring now to FIGS. 17 A, 17B and 18A-18C, another embodiment of an anvil 1400 includes an anvil head 1402 and an anvil shaft 1404. Similar to previous embodiments, anvil shaft 1404 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1402 is movable between a collapsed or folded configuration (see FIG. 18A) and an expanded or dome-shaped configuration (see FIG. 18C). Head 1402 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1404) in the collapsed configuration than in the expanded configuration.

[00124] As shown in FIGS. 18A-18C, anvil head 1402 comprises a plurality of leaves or petals 1406 coupled to each other such that the petals 1406 overlap with each other in the folded configuration. Upon expansion, petals 1406 are configured to form a substantially domed or umbrella shape with a convex outer surface 1440 having an apex 1442 and a concave inner surface 1436 (see FIGS. 17A and 17B). Apex 1442 may be coupled to a distal end portion of shaft 1404. Alternatively, petals 1406 may be configured to expand further such that anvil head 1402 has a substantially flat or circular disc shape in the expanded configuration (similar to previous embodiments). Head 1402 may include at least two petals 1406, or three or more petals 1406.

[00125] One or more of the petals 1406 (or all of the pedals) comprise a tissue contacting surface 1436 that comprises staple forming pockets (not shown) for receiving staples from staple assembly 120. The petals 1406 are configured such that, in the expanded configuration, the staple pockets are configured to align with the staples in staple assembly 120. In certain embodiments, each of the petals 1406 comprises one or more staple forming pockets. In other embodiments, the staple forming pockets may alternate between pedals 1406 such that, for example, one pedal may contain a staple forming pocket while its adjacent pedals do not contain a staple forming pocket.

[00126] In this embodiment, petals 1406 are designed to overlap with each other in both the expanded and collapsed or folded configurations. Thus, in the expanded configuration, petals 406 overlap with each other to provide mutual support and rigidity to anvil head 1402 such that it can resist the forces of the stapling operation. Anvil 1400 may further include a driver (not shown) within shaft 1404 that has a distal end portion coupled to head 1402 for expanding and collapsing pedals 1406. For example, anvil head 1402 may include one or more rigid elements coupled to pedals 1406 designed to telescope or move radially outward to push pedals outward and expand head 1402. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The actuator may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00127] Referring now to FIGS. 19A and 19B, another embodiment of an anvil 1500 includes an anvil head 1502 and an anvil shaft 1504. As with previous embodiments, anvil shaft 1504 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1502 is movable between a collapsed or folded configuration (see FIG. 19B) and an expanded or dome-shaped configuration (see FIG. 19A). Head 1502 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1504) in the folded configuration than in the dome-shaped configuration.

[00128] Anvil head 1502 comprises a plurality leaves or petals 1506 coupled to each other such that the petals 1506 overlap with each other in the folded configuration. Upon expansion, petals 1506 are configured to form a substantially domed or umbrella shape with a convex outer surface 1508 and a concave inner surface (not shown). Alternatively, petals 1506 may be configured to expand further such that anvil head 1502 has a substantially flat or circular disc shape in the expanded configuration. Head 1502 may include at least two petals 1506, or three or more petals 1506.

[00129] One or more of the petals 1506 (or all of the pedals) have a tissue contacting surface comprising one or more staple forming pockets (not shown) for receiving staples from the staple assembly 120. The petals 1506 are configured such that, in the expanded configuration, the staple pockets are configured to align with the staples in staple assembly 120. In certain embodiments, each of the petals 1506 comprises one or more staple forming pockets. In other embodiments, the staple forming pockets may alternate between pedals 1506 such that, for example, one pedal may contain a staple forming pocket while its adjacent pedals do not contain a staple forming pocket.

[00130] Anvil head 1502 further comprises one or more substantially rigid elements or rods 1510 extending substantially from a proximal surface edge 1512 to a central portion or apex 1514 of head 1502. Rods 1510 are configured to expand outward with petals 1506 and provide stability and rigidity to head 1502 in the expanded configuration. Rods 1510 may include one or more ridges or other surface features thereon to provide additional stability to head 1502 as it is expanded. Rods 1510 are configured to pivot at apex 1514 and proximal surface 1512 to allow transformation of anvil head 1502 between the expanded and collapsed configurations.

[00131] In some embodiments, anvil head 1502 may further include one or more cables extending around head 1502 to transition the head between the collapsed and expanded configurations. In one such embodiment, head 1502 comprise a lower cable 1530 and an upper cable 1532. Lower cable 1530 is disposed in a proximal region of pedals 1506 near proximal surface 1512 and upper cable 1532 is disposed in a distal region of head 1502 near apex 1514. Cables 1530, 1532 are coupled to one or more driver(s) (not shown) that extend through shaft 1504 of anvil 1500 and are configured to tension cables 1530, 1532 to expand anvil head 1502 into the umbrella or dome shape. The driver(s) (not shown) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00132] Referring now to FIGS. 20A-20C, another embodiment of an anvil 1600 includes an anvil head 1602 and an anvil shaft 1604. Similar to previous embodiments, anvil shaft 1604 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1602 is movable between a collapsed or folded configuration (see FIG. 20 A) and an expanded or dome-shaped configuration (see FIGS. 20B and 20C). Head 1602 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1604) in the collapsed configuration than in the expanded configuration.

[00133] As shown in FIG. 20A, anvil head 1602 comprises a plurality leaves or petals 1606 coupled to each other such that the petals 1606 overlap with each other in the collapsed configuration. Upon expansion, petals 1606 are configured to form a substantially domed or umbrella shape with a convex outer surface 1608 and a concave inner surface 1612. Alternatively, petals 1606 may be configured to expand further such that anvil head 1602 has a substantially flat or circular disc shape in the expanded configuration. Head 1602 may include at least two petals 1606, or three or more petals 1606.

[00134] One or more of the petals 1606 (or all of the pedals) comprise a tissue contacting surface 1636 defining staple forming pockets (not shown) for receiving staples 200. The petals 1606 are configured such that, in the expanded configuration, the staple pockets are configured to align with the staples in staple assembly 120 (i.e., such that the staple legs or tines align with the staple bays or pockets so that the staples form properly. In certain embodiments, each of the petals 1606 comprises one or more staple forming pockets. In other embodiments, the staple forming pockets may alternate between pedals 1606 such that, for example, one pedal may contain a staple forming pocket while its adjacent pedals do not contain a staple forming pocket.

[00135] Similar to previous embodiments, anvil 1600 may further include one or more driver(s) (not shown) within shaft 1604 that each have a distal end portion coupled to head 1602 for expanding and collapsing pedals 1606. For example, anvil head 1602 may include one or more rigid elements coupled to pedals 1606 designed to telescope or move radially outward to push pedals outward and expand head 1602. Alternatively, the driver(s) may be disposed within the circular stapler assembly 120, or within a separate anvil delivery instrument (not shown). The driver(s) may have a proximal end coupled to a suitable actuation mechanism (discussed in more detail below).

[00136] In this embodiment, anvil 1600 further comprises an expandable element 1610, such as a balloon or the like, configured to expand and apply pressure to outer surface 1608 of head 1602. This ensures that the staple pocket plane is capable of resisting the force from the clamping of tissue and then from the firing and cutting forces. Balloon 1610 may be inflated in any suitable manner, such as fluid inflation (e.g., air or other gases, or fluid), chemical inflation or (e.g., mixing certain materials together to form an expanding gas within the balloon) and the like. In one embodiment, balloon 1610 comprises a proximal end configured for coupling to a suitable fluid source, such as carbon dioxide, saline or the like. The fluid source may be any suitable source, such as a carbon dioxide tank under pressure, a syringe filled with gas to fluid, such as saline, or a source of insufflation.

[00137] Referring now to FIGS. 21 A, 21B and 22A-22C, another embodiment of an anvil 1700 includes an anvil head 1702 and an anvil shaft 1704. Anvil shaft 1704 is insertable into an internal channel of staple assembly 120 and is removably and slidably securable therein. Anvil head 1702 is movable between a collapsed configuration (see FIG. 23 A) and an expanded configuration (see FIG 23C). Head 1702 has a smaller cross-sectional area or lateral dimension (relative to the longitudinal axis of shaft 1704) in the collapsed configuration than in the expanded configuration.

[00138] In this embodiment, anvil head 1702 comprises an expandable element 1710, such as a balloon or the like. Balloon 1710 may be inflated in any suitable manner, such as fluid inflation (e.g., air or other gases, or fluid), chemical inflation or (e.g., mixing certain materials together to form an expanding gas within the balloon) and the like. In one embodiment, balloon 1710 comprises a proximal end configured for coupling to a suitable fluid source, such as carbon dioxide, saline or the like. The fluid source may be any suitable source, such as a carbon dioxide tank under pressure, a syringe filled with gas to fluid, such as saline, or a source of insufflation.

[00139] Anvil 1700 further comprises an annular film 1720 having an inner surface 1722 with a larger diameter than shaft 1704. Film 1720 includes a tissue contacting surface 7136 defining staple forming pockets (not shown) for receiving staples 200. Film 1720 preferably comprises any suitable material, such as metal or a hard polymer, having sufficient stiffness to configured to resist the forces applied by clamping of tissue and then from the firing and cutting forces of the stapler assembly.

[00140] In one embodiment, film 1720 is coupled to a proximal surface of balloon 1710 (see FIGS. 22A-22C). Film 1720 may be configured to expand radially outward as the balloon 1710 is inflated such that, in the expanded configuration, the staple pockets are configured to align with the staples in staple assembly 120 (i.e., such that the staple legs or tines align with the staple bays or pockets so that the staples form properly). In another embodiment, film 1720 is configured to advance along anvil shaft 1704 in the distal direction after balloon 1710 has been expanded. In this embodiment, film 1720 may be configured to expand via a separate actuator after film 1720 has been advanced in contact with balloon 1710. Balloon 1710 is configured to apply pressure to a distal surface of film 1720 to ensure that film 1720 resists the forces applied during the stapling operation.

[00141] The proximal end portion of the anvils described above are operatively connected to one or more drivers or actuation mechanisms (not shown), although as those skilled in the art reading this description will appreciate, components of the drivers may extend into, and/or pass through the anvil shafts and/or the stapler instrument 100. In various embodiments, the anvils and/or instrument 100 will include a proximal handle (not shown) for actuating the drivers that move the anvils between the collapsed and expanded configurations, and, in some embodiments, for controlling the orientation and movement of the anvils. Alternatively, the system may include an anvil delivery instrument that includes one or more drivers for expanding and collapsing the anvils.

[00142] Referring now to FIG. 23, an anvil delivery instrument 1800 includes an elongate shaft 1802 sized to advance through a suitable percutaneous penetration in the patient, such as a trocar, cannular and the like. In certain embodiments, shaft 1802 has an outer dimension of less than about 14 mm, although it will be recognized that the dimensions of shaft 1802 may vary depending on the surgical procedure and the size of the percutaneous entry point into the patient.

[00143] Instrument 1800 further includes first and second jaws 1804, 1806, that are movable between open and closed positions relative to each other. In certain embodiments, second jaw 1806 is a movable jaw configured to move from an open position to a closed position relative to first jaw 1804. In other embodiments, first jaw 1804 is a movable jaw configured to move between open and closed positions relative to second jaw 1806. In the exemplary embodiment, both jaws 1804, 1806 are movable relative to each other.

[00144] Referring now to FIG. 27, jaws 1804, 1806 preferably pivot about a hinge that may include a pivot pin 1810 extending through a slot (not shown) in each of the jaws 1804, 1806. Instrument 1800 includes a driver (not shown) within shaft 1802 that opens and closes jaws 1804, 1806 about pivot pin 1810. Jaws 1804, 1806 may be opened and closed may any suitable mechanisms including, but not limited to, those described in any of the publications incorporated herein by reference. First and second jaws 1804, 1806 may also be capable of articulating together relative to shaft 1802 about an axis substantially perpendicular to the longitudinal axis (e.g., the yaw or pitch axes). In these embodiments, instrument 1800 may further include a wrist assembly (not shown) that allows jaws 1804, 1806 to articulate relative to shaft 1802.

[00145] In an exemplary embodiment, jaws 1804, 1806 are configured to move into a substantially parallel position with each other in the closed position (as shown in FIG. 27). Jaws 1804, 1806 are preferably sized such that each jaw contacts and grips onto an outer surface of anvil shaft 1134 in the closed position. This configuration provides a stronger grip on shaft 1134 and inhibits the shaft from watermelon seeding from the jaws, as is the case with typical prior art instruments that do not close in a substantially parallel orientation.

[00146] In an exemplary embodiment, jaw 1804 includes a jaw grasping portion 1840 and a proximal support 1842. Proximal support 1842 extends downward towards a jaw grasping portion 1844 of jaw 1806 and is coupled thereto by pivot pin 1810. Proximal support 1842 is sized and shaped such that pivot pin 1810 is located closer to jaw grasping portion 1844 of jaw 1806 than jaw grasping portion 1842 of jaw 1804. Thus, pin 1810 and grasping portion 1842 are disposed on one side of a central longitudinal axis 1850 of shaft 1802 and jaw grasping portion 1840 is located on the other side of longitudinal axis 1850. This provides an asymmetrical location for the hinge or pivot point between jaws 1804, 1806 such that the jaws can be position in a closed position around shaft 1134 of anvil 1130 with substantially parallel surfaces facing shaft 1134.

[00147] Referring again to FIG. 23, delivery instrument 1800 includes a driver for moving anvil head 1132 between the collapsed and expanded configurations. In one embodiment, the driver comprises a rod 1820 that extends through shaft 1802. Rod 1820 includes a distal end portion 1822 configured to extend at least partially through jaws 1804, 1806. In one embodiment, rod 1820 is sized and configured to extend through an internal lumen (not shown) in anvil shaft 1134 and is configured for distal advancement through shaft 1134 to engage anvil head 1132 (see FIGS. 24 and 25). Rod 1820 includes an engagement mechanism (not shown) on distal end portion 1822 that cooperates with an engagement mechanism on anvil head 1134 to move anvil head 1132 between the collapsed and expanded configurations.

[00148] In one embodiment, rod 1820 includes a rotatable element (not shown) configured to rotate relative to rod 1820. In another embodiment, the entire rod 1820 is configured to rotate relative to shaft 1802. Rotation of rod 1820 or the rotation element causes central component 1140 of anvil head 1132 to pivot about a hinge on anvil shaft 1134 between the collapsed and expanded configurations. In addition, rotation of rod 1820 causes lateral components 1142, 1144 to pivot about hinges between lateral components 1142, 1414 and central component 1140. In an alternative embodiment, instrument 1800 includes a second driver on rod 1820 or on another element of instrument 1800 that causes lateral components 1142, 1144 to pivot relative to central component 1140 (i.e., movement of anvil head 1132 into the collapsed configuration may be caused by a single or multiple drivers in instrument 1800).

[00149] In another embodiment, distal end portion 1822 of rod 1820 is configured to actuate anvil head 1132 through a push-pull mechanism. For example, longitudinal movement of rod 1820 relative to instrument 1800 causes central component 1140 to pivot about anvil shaft 1134 and/or lateral components 1142, 1144 to pivot about central component 1140.

[00150] The proximal end portion of instrument 1800 is operatively connected to an actuation mechanism (not shown), although as those skilled in the art reading this description will appreciate, components of the actuation mechanism may extend into, and/or pass through instrument 1800. In various embodiments, instrument 1800 will include a proximal handle (not shown) for actuating jaws 1804, 1806 and rod 1820 and, in some embodiments, for controlling the orientation and movement of the distal end portion of instrument 1800. In other embodiments, instrument 1800 is adapted to be used with a robotic system. In these embodiments, instrument 1800 will generally include an actuation mechanism that controls the orientation and movement of the end effector, the opening and closing of jaws 1804, 1806 and the actuation of rod 1820. The actuation mechanism will typically be controlled by a robotic manipulator assembly that is controlled remotely by a user. For example, in one configuration, the actuation mechanism will be manipulated by the robotic manipulator assembly to either rotate rod 1820 or move rod 1820 in the longitudinal direction for expanding and collapsing anvil 1130.

[00151] The surgical instruments described herein may be coupled to a proximal control system that monitors and controls the linkages or discs in the wrist assembly for articulating end effector 110 relative to shaft 105 and for translating drive member 190 distally and proximally to deploy staples 200 and cutting element 160. In addition, the control system may monitor and control the longitudinal location of drive member 190 relative to each of the staple assembly 170 and the cutting assembly 160. In addition, the control system may monitor and control one or more actuators that move the anvil between open and closed positions and/or control operation of the anvil delivery instrument 1800. This control system may be a manual control system with user interfaces that allow the user to control each of the functions of the instrument, or it may be an automatic control system that monitors and controls these functions. In some embodiments, the control system is a combination of manual and automatic that allows the user to adjust or control certain functions, while automatically limiting those functions within certain ranges or parameters.

[00152] In certain embodiments, the instrument may include sensors (not shown) for detecting a location of drive member 190. The sensors may include any suitable sensors for detecting location, force and/or torque. In one embodiment, the sensors include fiber optic bend sensors, such as Fiber Bragg Gratings (FBG) for providing strain measurements in the jaws, the tension bands and/or other components of the surgical instrument. Various systems and methods for monitoring the shape and relative position of an optical fiber in three dimensions are described in U.S. patent application publication no. 2006/0013523, filed on Jul. 13, 2005, and U.S. Pat. No. 6,389,187, filed on Jun. 17, 1998, the completed disclosures of which are incorporated herein by reference for all purposes.

[00153] The control system may include one or more processors (e.g., microprocessor, microchip, or application-specific integrated circuit), one or more memory devices (e.g., random-access memory and/or read-only memory), and I/O interface and/or a communication interface. The processors may include one or more computer-readable storage devices and/or software applications that store program instructions that allow the processor(s) to compare the detected torque or force with the prescribed range. The VO devices can include one or more devices that enable the user to interact with the system (e.g., a user interface). The I/O devices can include, for example, a touchscreen display, a keypad, one or more selectors, one or more indicators.

[00154] Although described as a processor, it is to be appreciated that the controllers may be implemented in practice by any combination of hardware, software and firmware. Also, their functions as described herein may be performed by one unit, or divided up among different components, each of which may be implemented in turn by any combination of hardware, software and firmware.

[00155] With reference to Fig. 28, an exemplary embodiment of a teleoperated surgical instrument 500 that may support a previously described instrument is depicted. As shown, the instrument 500 generally includes a proximal housing 510 at its proximal end and coupled to shaft 520 of the instrument and a circular stapling assembly 530 at the distal end of shaft 520. Proximal housing 510 may include an instrument memory or storage device (not shown). The memory can perform a number of functions when the instrument is loaded on a manipulator arm (not shown) of a robotic control system. For example, the memory can provide a signal verifying that the instrument is compatible with that particular surgical system. Additionally, the memory may identify the instrument and end effector type (whether it is a scalpel, a needle grasper, jaws, scissors, a clip applier, an electrocautery blade, or the like) to the surgical system so that the system can reconfigure its programming to take full advantage of the instrument's specialized capabilities. As further discussed below, the memory may include specifics on the architecture of the instrument, and include particular values that should be employed in control algorithms, such as tool compliance and gain values.

[00156] Proximal housing 510 also may include a force/torque drive transmission mechanism (not shown) for receiving output from the motors of the manipulator arm. The force/torque drive transmission mechanism transmits the output from the motors to an end effector 530 of the instrument through an instrument shaft 520 mounted to the transmission mechanism. Exemplary surgical robotic instruments, instrument/manipulator arm interface structures, and data transfer between the instruments and servomechanism is more fully described in U.S. Pat. No. 6,331,181, the full disclosure of which is incorporated herein by reference.

[00157] As noted above, the present surgical instruments may be employed in a robotic teleoperated surgical system. FIG. 29 illustrates, as an example, a top view of an operating room employing a robotic surgical system. The robotic surgical system in this case is a robotic surgical system 600 including a Console (“C”) utilized by a Surgeon (“S”) while performing a minimally invasive diagnostic or surgical procedure, usually with assistance from one or more Assistants (“A”), on a Patient (“P”) who is lying down on an Operating table (“O”).

[00158] The servomechanism used for telesurgery will often accept input from two master controllers (one for each of the surgeon's hands) and may include two or more robotic arms. A surgical instrument is mounted on each of the robotic arms. Operative communication between master controllers and associated robotic arm and instrument assemblies is typically achieved through a control system. The control system typically includes at least one processor that relays input commands from the master controllers to the associated robotic arm and instrument assemblies and back in the case of, for example, force feedback or the like. One example of a robotic surgical system is the DA VINCI™ system commercialized by Intuitive Surgical, Inc. of Sunnyvale, California.

[00159] A variety of structural arrangements have been used to support the surgical instrument at the surgical site during robotic surgery. The driven linkage or "slave" is often called a robotic surgical manipulator, and exemplary linkage arrangements for use as a robotic surgical manipulator during minimally invasive robotic surgery are described in U.S. Pat. Nos. 7,594,912, 6,758,843, 6,246,200, and 5,800,423, the full disclosures of which are incorporated herein by reference in their entirety for all purposes. These linkages often manipulate an instrument holder to which an instrument having a shaft is mounted. Such a manipulator structure can include a parallelogram linkage portion that generates motion of the instrument holder that is limited to rotation about a pitch axis that intersects a remote center of manipulation located along the length of the instrument shaft. Such a manipulator structure can also include a yaw joint that generates motion of the instrument holder that is limited to rotation about a yaw axis that is perpendicular to the pitch axis and that also intersects the remote center of manipulation. By aligning the remote center of manipulation with the incision point to the internal surgical site (for example, with a trocar or cannula at an abdominal wall during laparoscopic surgery), an end effector of the surgical instrument can be positioned safely by moving the proximal end of the shaft using the manipulator linkage without imposing potentially hazardous forces against the abdominal wall. Alternative manipulator structures are described, for example, in U.S. Pat. Nos. 6,702,805, 6,676,669, 5,855,583, 5,808,665, 5,445,166, and 5,184,601, the full disclosures of which are incorporated herein by reference in their entirety for all purposes.

[00160] During the surgical procedure, the telesurgical system can provide mechanical actuation and control of a variety of surgical instruments or tools having end effectors that perform various functions for the surgeon, for example, holding or driving a needle, grasping a blood vessel, dissecting tissue, or the like, in response to manipulation of the master input devices. Manipulation and control of these end effectors is a particularly beneficial aspect of robotic surgical systems. For this reason, it is desirable to provide surgical tools that include mechanisms that provide two or three degrees of rotational movement of an end effector to mimic the natural action of a surgeon's wrist. Such mechanisms should be appropriately sized for use in a minimally invasive procedure and relatively simple in design to reduce possible points of failure. In addition, such mechanisms should provide an adequate range of motion to allow the end effector to be manipulated in a wide variety of positions.

[00161] The Console includes a monitor 604 for displaying an image of a surgical site to the Surgeon, left and right manipulatable control devices 608 and 609, a foot pedal 605, and a processor 602. The control devices 608 and 609 may include any one or more of a variety of input devices such as joysticks, gloves, trigger-guns, hand-operated controllers, or the like. The processor 602 may be a dedicated computer that may be integrated into the Console or positioned next to it.

[00162] The Surgeon performs a minimally invasive surgical procedure by manipulating the control devices 608 and 609 (also referred to herein as “master manipulators”) so that the processor 602 causes their respectively associated robotic arm assemblies, 628 and 629, (also referred to herein as “slave manipulators”) to manipulate their respective removably coupled surgical instruments 638 and 639 (also referred to herein as “tools”) accordingly, while the Surgeon views the surgical site in 3-D on the Console monitor 604 as it is captured by a stereoscopic endoscope 640.

[00163] Each of the tools 638 and 639, as well as the endoscope 640, may be inserted through a cannula or other tool guide (not shown) into the Patient so as to extend down to the surgical site through a corresponding minimally invasive incision such as incision 666. Each of the robotic arms is conventionally formed of links, such as link 662, which are coupled together and manipulated through motor controlled or active joints, such as joint 663.

[00164] The number of surgical tools used at one time and consequently, the number of robotic arms being used in the system 600 will generally depend on the diagnostic or surgical procedure and the space constraints within the operating room, among other factors. If it is necessary to change one or more of the tools being used during a procedure, the Assistant may remove the tool no longer being used from its robotic arm, and replace it with another tool 331 from a Tray (“T”) in the operating room.

[00165] The monitor 604 may be positioned near the Surgeon's hands so that it will display a projected image that is oriented so that the Surgeon feels that he or she is actually looking directly down onto the operating site. To that end, images of the tools 638 and 639 may appear to be located substantially where the Surgeon's hands are located.

[00166] The processor 602 performs various functions in the system 600. One function that it performs is to translate and transfer the mechanical motion of control devices 608 and 609 to their respective robotic arms 628 and 629 through control signals overbus 610 so that the Surgeon can effectively manipulate their respective tools 638 and 639. Another important function is to implement various control system processes as described herein.

[00167] Robotic surgery systems and methods are further described in U.S. Pat. No. 5,797,900, filed on May 16, 1997, issued on Aug. 25, 1998, U.S. Pat. No. 6, 132,368, filed on Nov. 21, 1997, issued on Oct. 17, 2000, U.S. Pat. No. 6,331,181, filed on Oct. 15, 1999, issued on Dec. 18, 2001, U.S. Pat. No. 6,441 ,577, filed on Apr. 3, 2001, issued on Aug. 27, 2002, U.S. Pat. No. 6,902,560, filed on Jan. 6, 2004, issued on Jun. 7, 2005, U.S. Pat. No. 6,936,042, filed on Apr. 16, 2002, issued on Aug. 30, 2005, and U.S. Pat. No. 6,994,703, filed on Dec. 4, 2002, issued on Feb. 7, 2006, the full disclosures of which are incorporated herein by reference for all purposes. A suitable robotic surgical system currently in use is the da Vinci S Surgical System by Intuitive Surgical, Inc.

[00168] FIG. 30 illustrates, as an example, a side view of a simplified (not necessarily in proportion or complete) illustrative robotic arm assembly 700 (which is representative of robotic arm assemblies 628 and 629) holding a surgical instrument 750 (which is representative of tools 638 and 639) for performing a surgical procedure. The surgical instrument 750 is removably held in tool holder 740. The arm assembly 700 is mechanically supported by a base 701, which may be part of a patient-side movable cart or affixed to the operating table or ceiling. It includes links 702 and 703 which are coupled together and to the base 701 through setup joints 704 and 705.

[00169] The setup joints 704 and 705 in this example are passive joints that allow manual positioning of the arm 700 when their brakes are released. For example, setup joint 704 allows link 702 to be manually rotated about axis 706, and setup joint 705 allows link 703 to be manually rotated about axis 707.

[00170] Although only two links and two setup joints are shown in this example, more or less of each may be used as appropriate in this and other robotic arm assemblies described herein. For example, although setup joints 704 and 705 are useful for horizontal positioning of the arm 700, additional setup joints may be included and useful for limited vertical and angular positioning of the arm 700. For major vertical positioning of the arm 700, however, the arm 700 may also be slidably moved along the vertical axis of the base 701 and locked in position.

[00171] The robotic arm assembly 700 also includes three active joints driven by motors. A yaw joint 710 allows arm section 730 to rotate around an axis 761, and a pitch joint 720 allows arm section 730 to rotate about an axis perpendicular to that of axis 761and orthogonal to the plane of the drawing. The arm section 730 is configured so that sections 731 and 732 are always parallel to each other as the pitch joint 720 is rotated by its motor. As a consequence, the instrument 770 may be controllably moved by driving the yaw and pitch motors so as to pivot about the pivot point 762, which is generally located through manual positioning of the setup joints 704 and 705 so as to be at the point of incision into the patient. In addition, an insertion gear 745 may be coupled to a linear drive mechanism (not shown) to extend or retract the instrument 750 along its axis 763.

[00172] Although each of the yaw, pitch and insertion joints or gears, 710, 720 and 745, is controlled by an individual joint or gear controller, the three controllers are controlled by a common master/slave control system so that the robotic arm assembly 700 (also referred to herein as a “slave manipulator”) may be controlled through user (e.g., surgeon) manipulation of its associated master manipulator.

[00173] While several embodiments have been shown in the drawings, it is not intended that the description be limited thereto, as it is intended that the description be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of presently disclosed embodiments. Thus the scope of the embodiments should be determined by the appended claims and their legal equivalents, rather than by the examples given.

[00174] Further, this description's terminology is not intended to limit the devices described herein. The term “force” is to be construed as encompassing both force and torque, unless otherwise indicated herein or clearly contradicted by context. The terms “tools” and “instruments” are used interchangeably herein to refer to the surgical instruments. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” and any singular use of any word, include plural referents unless expressly and unequivocally limited to one referent. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The terms “connected” and “coupled” are to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening.

[00175] Spatially relative terms — such as “proximal” and “distal — may be used to describe one element's or feature's relationship to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass different positions (i.e., locations) and orientations (i.e., rotational placements) of a device in use or operation in addition to the position and orientation shown in the figures. For example, the terms “proximal” and “distal” are relative terms, where the term “distal” refers to the portion of the object furthest from an operator of the instrument and closest to the surgical site, such as the opening of the tool cover or the end effector of the instrument. The term “proximal” indicates the relative proximity to the operator of the surgical instrument and refers to the portion of the object closest to the operator and furthest from the surgical site. In this application, an end effector refers to a tool installed at the distal end of an instrument, including but not limited to forceps or graspers, needle drivers, scalpels, scissors, spatulas, blades, and other tools, which may or may not use energy to cauterize tissue (i.e., a monopolar or bipolar tool).

[00176] Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Various alternatives and modifications can be devised by those skilled in the art without departing from the disclosure. Accordingly, the present description is intended to embrace all such alternatives, modifications and variances. As well, one skilled in the art will appreciate further features and advantages of the present disclosure based on the above-described embodiments. Accordingly, the present description is not to be limited by what has been particularly shown and described, except as indicated by the appended claims.

[00177] For example, a first embodiment is circular surgical stapling instrument comprising: a staple assembly comprising a plurality of staples and a cutting element; an anvil positioned distal to the staple assembly; and a driver configured to sequentially advance the staples and the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly.

[00178] A second embodiment is the first embodiment, wherein the staples are deformed against the anvil before the cutting element advances distal of the staple assembly.

[00179] A third embodiment is any combination of the above embodiments, further comprising a first pusher coupled to the staples and a second pusher coupled to the cutting element, wherein the driver comprises a rotatable element coupled to the first and second pushers.

[00180] A 4^th embodiment is any combination of the above embodiments, wherein the rotation of the driver causes longitudinal movement of the first and second pushers.

[00181] A 5^th embodiment is any combination of the above embodiments, wherein the first pusher comprises a proximal cam surface and the driver comprises a distal protrusion configured to contact the proximal cam surface, wherein rotation of the driver causes the distal protrusion to move along the proximal cam surface.

[00182] A 6^th embodiment is any combination of the above embodiments, wherein the first pusher has a longitudinal axis, wherein the proximal cam surface comprises a first portion that extends at a transverse angle to a vertical plane substantially perpendicular to the longitudinal axis such that rotation of the driver and the distal protrusion translates the first pusher in a longitudinal direction.

[00183] A 7^th embodiment is any combination of the above embodiments, wherein the proximal cam surface comprises a second portion that is substantially parallel to said vertical plane such that movement of the distal protrusion along the second portion does not translate the first pusher in the longitudinal direction.

[00184] An 8^th embodiment is any combination of the above embodiments, wherein the second pusher comprises a proximal cam surface and wherein the distal protrusion of the driver is configured to contact the proximal cam surface, wherein rotation of the driver causes the distal protrusion to move along the proximal cam surface of the second pusher.

[00185] A 9^th embodiment is any combination of the above embodiments, wherein the proximal cam surface of the second pusher extends at a transverse angle to the vertical plane such that rotation of the driver and the distal protrusion translates the second pusher in a longitudinal direction.

[00186] A 10^th embodiment is any combination of the above embodiments, wherein the proximal cam surface of the second pusher is aligned with the second portion of the proximal cam surface of the first pusher such that the distal protrusion of the driver simultaneously contacts the proximal cam surface of the first pusher and the second portion of the proximal cam surface of the first pusher.

[00187] An 11^th embodiment is any combination of the above embodiments, wherein the first pusher comprises an internal channel and wherein the proximal cam surface of the second pusher extends through the internal channel.

[00188] A 12^th embodiment is any combination of the above embodiments, wherein the proximal cam surface of the second pusher extends proximally of the proximal cam surface of the first pusher.

[00189] A 13^th embodiment is any combination of the above embodiments, wherein the first and second portions of the proximal cam surface of the first pusher extend at least partially circumferentially about a longitudinal axis of the staple assembly.

[00190] A 14^th embodiment is any combination of the above embodiments, wherein the first and second portions of the proximal cam surface each extend about 180 degrees around the longitudinal axis.

[00191] A 15^th embodiment is any combination of the above embodiments, wherein the distal protrusion is a first distal protrusion, and wherein the driver comprises a second distal protrusion circumferentially spaced from the first distal protrusion.

[00192] A 16^th embodiment is any combination of the above embodiments, wherein the first pusher comprises a third portion of the proximal cam surface that extends at a transverse angle to the vertical plane, wherein the second distal protrusion contacts the third portion of the proximal cam surface such rotation of the driver and the second distal protrusion translates the first pusher in a longitudinal direction.

[00193] A 17^th embodiment is any combination of the above embodiments, wherein the second pusher comprises a second portion of the proximal cam surface that extends at a transverse angle to the vertical plane, wherein the second distal protrusion contacts the second portion of the proximal cam surface of the second pusher such rotation of the driver and the second distal protrusion translates the second pusher in a longitudinal direction.

[00194] An 18^th embodiment is any combination of the above embodiments, wherein the driver defines an internal channel, the instrument further comprising a capturing device configured to advance through the internal channel to engage the anvil.

[00195] A 19^th embodiment is any combination of the above embodiments, further comprising a staple cartridge coupled to the staple pusher, wherein the staples are disposed circumferentially around an internal channel within the staple cartridge.

[00196] A 20^th embodiment is any combination of the above embodiments, wherein the staple cartridge is removably coupled to the staple assembly.

[00197] A 21^st embodiment is any combination of the above embodiments, further comprising an elongate shaft with a wrist, wherein the stapling assembly is rotatably coupled to the shaft at the wrist.

[00198] A 22^nd embodiment is any combination of the above embodiments, wherein the driver extends through the wrist and comprises a flexible portion configured to bend as the stapling assembly rotates relative to the shaft.

[00199] A 23^rd embodiment is any combination of the above embodiments, further comprising an actuator coupled to a proximal end of the driver and configured to rotate the driver.

[00200] A 24^th embodiment is any combination of the above embodiments, wherein the actuator is configured for coupling to a robotic surgical system.

[00201] A 25^th embodiment is a circular surgical stapling instrument for joining tissue, the stapling instrument comprising: an elongate shaft; a staple assembly coupled to a distal end of the shaft, the staple assembly comprising a plurality of staples, a cutting element and a cam surface; and a driver comprising an engagement element for contacting the cam surface to advance the staples and the cutting element such that the staples contact the tissue before the cutting element is advanced distal of the staple assembly.

[00202] A 26^th embodiment is the 25^th embodiment and any combination of the above embodiments.

[00203] A 27^th embodiment is any combination of the above embodiments, further comprising a first pusher coupled to the staples and a second pusher coupled to the cutting element, wherein the engagement element of the driver comprises a rotatable element configured to contact the cam surface such that rotation of the driver causes longitudinal movement of the first and second pushers.

[00204] A 28^th embodiment is any combination of the above embodiments, wherein the cutting element is proximally recessed from the staples before the driver advances the first and second pushers.

[00205] A 29^th embodiment is any combination of the above embodiments, wherein the driver advances the first pusher a first distance and the second pusher a second distance, wherein the second distance is greater than the first distance.

[00206] A 30^th embodiment is any combination of the above embodiments, wherein the first pusher comprises a proximal cam surface and the second pusher comprises a proximal cam surface, wherein the proximal cam surfaces of the first and second pushers extend at a transverse angle to a vertical plane substantially perpendicular to a longitudinal axis of the staple assembly such that rotation of the driver translates the first and second pushers in a longitudinal direction.

[00207] A 31^st embodiment is any combination of the above embodiments, wherein the proximal cam surface of the first pusher extends at a first angle to said vertical plane and the proximal cam surface of the second pusher extends at a second angle to said vertical plane, wherein the first angle is greater than the second angle.

[00208] A 32^nd embodiment is any combination of the above embodiments, further comprising an anvil positioned distal to the staple assembly, wherein the driver is configured to advance the staples and then the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly.

[00209] A 33^rd embodiment is any combination of the above embodiments, wherein the driver defines an internal channel, the instrument further comprising a capturing device configured to advance through the internal channel to engage the anvil.

[00210] A 34^th embodiment is any combination of the above embodiments, wherein the driver extends through the wrist and comprises a flexible portion configured to bend as the stapling assembly rotates relative to the shaft.

[00211] A 35^th embodiment is any combination of the above embodiments, further comprising an actuator coupled to a proximal end of the driver and configured to rotate the driver.

[00212] A 36^th embodiment is any combination of the above embodiments, wherein the actuator is configured for coupling to a robotic surgical system.

[00213] A 37^th embodiment is a method of joining two tissue structures, the method comprising: positioning a staple assembly adjacent first and second tissue structures; advancing a plurality of staples into the first and second tissue structures to attach the first tissue structure to the second tissue structure; and advancing a cutting element through the first and second tissue structures after the staples have passed through the first and second tissue structures.

[00214] A 38^th embodiment is the 37^th embodiment and any combination of the above embodiments.

[00215] A 39^th embodiment is any combination of the above embodiments, further comprising rotating a driver to advance a first pusher coupled to the plurality of staples and a second pusher coupled to the cutting element.

[00216] A 40^th embodiment is any combination of the above embodiments, wherein the driver contacts the first pusher before the second pusher.

[00217] A 41^st embodiment is any combination of the above embodiments, further comprising advancing the staples into an anvil before the driver contacts the second pusher.

[00218] A 42^nd embodiment is any combination of the above embodiments, further comprising rotating an engagement element of the driver along an inclined cam surface of the first pusher and then rotating the engagement element along an inclined cam surface of the second pusher.

[00219] A 43^rd embodiment is any combination of the above embodiments, further comprising rotating the engagement element of the driver along a flat cam surface of the first pusher while the engagement element is in contact with the inclined cam surface of the second pusher.

[00220] A 44^th embodiment is any combination of the above embodiments, wherein the first and second tissue structures comprise first and sections of an intestine

[00221] A 45^th embodiment is any combination of the above embodiments, wherein the anvil comprises a head and a shaft, wherein the head comprises a tissue contacting surface defining staple forming pockets.

[00222] A 46^th embodiment is any combination of the above embodiments, wherein the anvil head comprises first and second components movable relative to each other and configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

[00223] A 47^th embodiment is any combination of the above embodiments, wherein the head comprises a plurality of petals each comprising a tissue contacting surface defining staple forming pockets and wherein the petals are configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

[00224] A 48^th embodiment is any combination of the above embodiments, wherein the anvil comprises an expandable element coupled to the annular tissue contact surface and configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

[00225] A 49^th embodiment is any combination of the above embodiments, further comprising a delivery instrument comprising an elongate shaft with first and second jaws movable between open and closed position and a driver extending through the shaft, the driver including an engagement mechanism for engaging the anvil and moving the anvil between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

[00226] A 50^th embodiment is a circular stapling system comprising: a surgical instrument comprising: a staple assembly comprising a plurality of staples; a cutting element; a driver configured to sequentially advance the staples and the cutting element; and an anvil movable between a collapsed configuration and an expanded configuration; and a delivery instrument including an engagement mechanism for engaging the anvil and moving the anvil between the collapsed configuration and the expanded configuration.

[00227] A 51^st embodiment is the 50^th embodiment and any combination of the above embodiments.

Claims

1. A circular stapling instrument comprising: a staple assembly comprising a plurality of staples and a cutting element; an anvil positioned distal to the staple assembly; and a driver configured to sequentially advance the staples and the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly.

2. The circular stapler instrument of claim 1, wherein the staples are deformed against the anvil before the cutting element advances distal of the staple assembly.

3. The circular stapling instrument of any one of claims 1 to 2, further comprising a first pusher coupled to the staples and a second pusher coupled to the cutting element, wherein the driver comprises a rotatable element coupled to the first and second pushers.

4. The circular stapling instrument of claim 3, wherein the rotation of the driver causes longitudinal movement of the first and second pushers.

5. The circular stapling instrument of any of claims 3 to 4, wherein the first pusher comprises a proximal cam surface and the driver comprises a distal protrusion configured to contact the proximal cam surface, wherein rotation of the driver causes the distal protrusion to move along the proximal cam surface.

6. The circular stapling instrument of claim 5, wherein the first pusher has a longitudinal axis, wherein the proximal cam surface comprises a first portion that extends at a transverse angle to a vertical plane substantially perpendicular to the longitudinal axis such that rotation of the driver and the distal protrusion translates the first pusher in a longitudinal direction.

7. The circular stapling instrument of 6, wherein the proximal cam surface comprises a second portion that is substantially parallel to said vertical plane such that movement of the distal protrusion along the second portion does not translate the first pusher in the longitudinal direction.

8. The circular stapling instrument of claim 7, wherein the second pusher comprises a proximal cam surface and wherein the distal protrusion of the driver is configured to contact the proximal cam surface, wherein rotation of the driver causes the distal protrusion to move along the proximal cam surface of the second pusher.

9. The circular stapling instrument of claim 8, wherein the proximal cam surface of the second pusher extends at a transverse angle to the vertical plane such that rotation of the driver and the distal protrusion translates the second pusher in a longitudinal direction.

10. The circular stapling instrument of claim 9, wherein the proximal cam surface of the second pusher is aligned with the second portion of the proximal cam surface of the first pusher such that the distal protrusion of the driver simultaneously contacts the proximal cam surface of the first pusher and the second portion of the proximal cam surface of the first pusher.

11. The circular stapling instrument of any of claims 8 to 10, wherein the first pusher comprises an internal channel and wherein the proximal cam surface of the second pusher extends through the internal channel.

12. The circular stapling instrument of any of claims 8 to 11, wherein the proximal cam surface of the second pusher extends proximally of the proximal cam surface of the first pusher.

13. The circular stapling instrument of any of claims 7 to 12, wherein the first and second portions of the proximal cam surface of the first pusher extend at least partially circumferentially about a longitudinal axis of the staple assembly.

14. The circular stapling instrument of any of claims 7 to 13, wherein the first and second portions of the proximal cam surface each extend about 180 degrees around the longitudinal axis.

15. The circular stapling instrument of any of claims 5 to 14, wherein the distal protrusion is a first distal protrusion, and wherein the driver comprises a second distal protrusion circumferentially spaced from the first distal protrusion.

16. The circular stapling instrument of claim 15, wherein the first pusher comprises a third portion of the proximal cam surface that extends at a transverse angle to the vertical plane, wherein the second distal protrusion contacts the third portion of the proximal cam surface such rotation of the driver and the second distal protrusion translates the first pusher in a longitudinal direction.

17. The circular stapling instrument of claim 16, wherein the second pusher comprises a second portion of the proximal cam surface that extends at a transverse angle to the vertical plane, wherein the second distal protrusion contacts the second portion of the proximal cam surface of the second pusher such rotation of the driver and the second distal protrusion translates the second pusher in a longitudinal direction.

18. The circular stapling instrument of any of claims 1 to 17, wherein the driver defines an internal channel, the instrument further comprising a capturing device configured to advance through the internal channel to engage the anvil.

19. The circular stapling instrument of any of claims 1 to 18, further comprising a staple cartridge coupled to the staple pusher, wherein the staples are disposed circumferentially around an internal channel within the staple cartridge.

20. The circular stapling instrument of claim 19, wherein the staple cartridge is removably coupled to the staple assembly.

21. The circular stapling instrument of any of claims 1 to 20, further comprising an elongate shaft with a wrist, wherein the stapling assembly is rotatably coupled to the shaft at the wrist.

22. The circular stapling instrument of claim 21, wherein the driver extends through the wrist and comprises a flexible portion configured to bend as the stapling assembly rotates relative to the shaft.

23. The circular stapling instrument of any of claims 1 to 22, further comprising an actuator coupled to a proximal end of the driver and configured to rotate the driver.

24. The circular stapling instrument of claim 23, wherein the actuator is configured for coupling to a robotic surgical system.

25. The circular stapling instrument of any of claims 1 to 24, wherein the anvil comprises a head and a shaft, wherein the head comprises a tissue contacting surface defining staple forming pockets.

26. The circular stapling instrument of claim 25, wherein the anvil head comprises first and second components movable relative to each other and configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

27. The circular stapling instrument of claim 25, wherein the head comprises a plurality of petals each comprising a tissue contacting surface defining staple forming pockets and wherein the petals are configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

28. The circular stapling instrument of claim 25, wherein the anvil comprises an expandable element coupled to the annular tissue contact surface and configured for deploying between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

29. The circular stapling instrument of any of claims 1 to 28, further comprising a delivery instrument comprising an elongate shaft with first and second jaws movable between open and closed position and a driver extending through the shaft, the driver including an engagement mechanism for engaging the anvil and moving the anvil between a collapsed configuration with a first lateral dimension and an expanded configuration with a second lateral dimension, wherein the first lateral dimension is smaller than the second lateral dimension.

30. A circular stapling instrument for joining tissue, the stapling instrument comprising: an elongate shaft; a staple assembly coupled to a distal end of the shaft, the staple assembly comprising a plurality of staples, a cutting element and a cam surface; and a driver comprising an engagement element for contacting the cam surface to advance the staples and the cutting element such that the staples contact the tissue before the cutting element is advanced distal of the staple assembly.

31. The circular stapling instrument of claim 30, further comprising a first pusher coupled to the staples and a second pusher coupled to the cutting element, wherein the engagement element of the driver comprises a rotatable element configured to contact the cam surface such that rotation of the driver causes longitudinal movement of the first and second pushers.

32. The circular stapling instrument of claim 31, wherein the cutting element is proximally recessed from the staples before the driver advances the first and second pushers.

33. The circular stapling instrument of claim 32, wherein the driver advances the first pusher a first distance and the second pusher a second distance, wherein the second distance is greater than the first distance.

34. The circular stapling instrument of claim 33, wherein the first pusher comprises a proximal cam surface and the second pusher comprises a proximal cam surface, wherein the proximal cam surfaces of the first and second pushers extend at a transverse angle to a vertical plane substantially perpendicular to a longitudinal axis of the staple assembly such that rotation of the driver translates the first and second pushers in a longitudinal direction.

35. The circular stapling instrument of claim 34, wherein the proximal cam surface of the first pusher extends at a first angle to said vertical plane and the proximal cam surface of the second pusher extends at a second angle to said vertical plane, wherein the first angle is greater than the second angle.

36. The circular stapling instrument of any of claims 30 to 35, further comprising an anvil positioned distal to the staple assembly, wherein the driver is configured to advance the staples and then the cutting element such that the staples contact the anvil before the cutting element is advanced distal of the staple assembly.

37. The circular stapling instrument of claim 36, wherein the driver defines an internal channel, the instrument further comprising a capturing device configured to advance through the internal channel to engage the anvil.

38. The circular stapling instrument of any of claims 30 to 37, wherein the driver extends through the wrist and comprises a flexible portion configured to bend as the stapling assembly rotates relative to the shaft.

39. The circular stapling instrument of any of claims 30 to 38, further comprising an actuator coupled to a proximal end of the driver and configured to rotate the driver.

40. The circular stapling instrument of claim 39, wherein the actuator is configured for coupling to a robotic surgical system.

41. A method of joining two tissue structures, the method comprising: positioning a staple assembly adjacent first and second tissue structures; advancing a plurality of staples into the first and second tissue structures to attach the first tissue structure to the second tissue structure; and advancing a cutting element through the first and second tissue structures after the staples have passed through the first and second tissue structures.

42. The method of claim 41, further comprising rotating a driver to advance a first pusher coupled to the plurality of staples and a second pusher coupled to the cutting element.

43. The method of claim 42, wherein the driver contacts the first pusher before the second pusher.

44. The method of any of claims 42 to 43, further comprising advancing the staples into an anvil before the driver contacts the second pusher.

45. The method of any of claims 42 to 44, further comprising rotating an engagement element of the driver along an inclined cam surface of the first pusher and then rotating the engagement element along an inclined cam surface of the second pusher.

46. The method of claim 45, further comprising rotating the engagement element of the driver along a flat cam surface of the first pusher while the engagement element is in contact with the inclined cam surface of the second pusher.

47. The method of any of claims 41 to 46, wherein the first and second tissue structures comprise first and sections of an intestine

48. A circular stapling system comprising: a surgical instrument comprising: a staple assembly comprising a plurality of staples; a cutting element; a driver configured to sequentially advance the staples and the cutting element; and an anvil movable between a collapsed configuration and an expanded configuration; and a delivery instrument including an engagement mechanism for engaging the anvil and moving the anvil between the collapsed configuration and the expanded configuration.