End effectors, surgical stapling devices, and methods of using same

An end effector for use by a surgeon to staple an anatomical structure of a patient during a minimally invasive procedure includes an anvil and a cartridge. The ends of the cartridge are coupled to the ends of the anvil. Each of the anvil and the cartridge is insertable through a trocar. The end effector is operable from outside the patient. A stapling device includes the end effector coupled to a manipulator via a shaft. The manipulator is accessible to the surgeon. The surgeon uses a clamping mechanism to selectively move the anvil and the cartridge to clamp the anatomical structure. A flexible member extends through the shaft and is coupled to at least one of the anvil and the cartridge and to the clamping mechanism. Operating the clamping mechanism withdraws the flexible member (46) from the end effector and clamps the anatomical structure between the anvil and the cartridge.

TECHNICAL FIELD

The invention relates to surgical staplers, and more particularly to end effectors and stapling devices and methods of using those devices in medical procedures.

BACKGROUND

Surgeons have implemented surgical staplers for many years. In general, there are three main types of linear surgical staplers—open linear staplers, open gastrointestinal anastomosis (i.e., a linear cutter), and endocutters. Staplers are often used in surgical procedures involving the lung, liver, and stomach and are typically used in resection of an organ.

Surgical staplers have some common components. These include a handle, an actuator, and an end effector including a clamping mechanism. The clamping mechanism often has a cartridge and an anvil. For these staplers, the surgeon clamps two members (i.e., the anvil and the cartridge) on the organ and compresses the organ between them. Once compressed, the surgeon uses the stapler to drive or fire staples through the organ. With proper compression and alignment of the clamping mechanism, a B-shaped staple is formed. Some surgical procedures may require multiple staple firings. Each firing often requires the surgeon to reload the stapler with more staples. For example, some staple lines may require 5 to 8 reloads depending on the length and/or the staple capacity of the stapler.

The integrity of a staple line depends on the proper formation of B-shaped staples. This in turn depends on the stapler's capability of compressing tissue while, at the same time, withstanding the forces associated with proper B-shaped staple formation. A B-shaped staple is the standard of care for gastrointestinal, vascular, pulmonary, and hepatic applications of surgical tissue fastening devices. Alignment in each of the X, Y, and Z axes of the clamping mechanism with itself (e.g., alignment of the anvil with the cartridge) on each side of the organ is necessary for proper formation of B-shaped staples.

Alignment difficulties are intensified by the trend toward minimally invasive surgical procedures in which the organ is remotely accessed through small incisions. A trocar or other cannula is inserted into each incision and becomes the access point into the body cavity for surgical devices, including staplers.

Typically, the surgeon inserts at least the end effector of the stapler through the trocar to perform the surgical procedure. By way of example, minimally invasive surgical procedures include a laparoscopic vertical sleeve gastrectomy. Due to this restricted spacial environment, minimally invasive surgical stapling devices must be relatively small compared to open linear surgical staplers. Minimally invasive devices are generally long (e.g., 35 cm to 45 cm) and thin (e.g., 5 mm to 15 mm diameter) devices. This long and thin configuration is necessary to fit through the trocar into the body cavity. The limited size presents a mechanical issue as B-shaped staple formation typically requires a pressure of about 100 psi. Under these pressures, small, less rigid, staplers deform and so prevent proper B-shaped staple formation.

Along the same lines, current devices used in minimally invasive surgical procedures have a fixed hinge at a proximal end. The hinge allows the anvil and cartridge to separate into a V-shaped configuration. Once separated, the surgeon may place the V around the organ and then collapse the V onto the organ. As the length of the anvil and cartridge increase, typically to provide a single, longer staple line across the organ, alignment between the anvil and the cartridge becomes more difficult, and the end effector is more difficult to manipulate through the trocar. Poor alignment is problematic, because with a hinge design, the anvil and/or cartridge at the most distant ends are more likely to be displaced from an ideal alignment due to deflection associated with the forces necessary to compress the tissue. Because of this deflection, the length of current V-shaped staplers for minimally invasive procedures is limited. As a result of this limitation, the anvil and the cartridge are limited in length. Limitations on length are problematic because this may require multiple staple reloads. Each reload may require the surgeon to withdraw the stapler from the trocar and then reinsert and reposition the stapler on the organ. Ultimately, these devices require more surgical time and are more likely to fail to provide consistent B-shaped staples when activated.

One solution to deflection is to provide two points of connection between the anvil and the cartridge instead of a single, hinged connection. That is, the anvil and the cartridge are coupled together at each end. However, this connection has been limited to open surgical procedures in which the surgeon has direct access to each end of the stapler and in which relatively large staplers may be utilized. In open surgery, the surgeon can directly manipulate one or both of the connections by hand. Furthermore, two-pointed connections require that the anvil and the cartridge extend beyond the full dimension of the organ. This requires a large device that, while possibly appropriate for open surgery, is not usable in minimally invasive procedures.

While current staplers are adequate, new devices and methods are needed to address the shortcomings of existing staplers and methods in minimally invasive surgical procedures. More particularly, new minimally invasive staplers and methods are needed that offer improved maneuverability and more uniform pressure application on the tissue, while providing consistent and quality resection lines created during medical procedures, such as during a vertical sleeve gastrectomy.

SUMMARY

An end effector for use by a surgeon to staple an anatomical structure of a patient during a minimally invasive procedure addresses these and other shortcomings and, in one embodiment, includes an anvil that includes a first end, a second end, and a face that is positionable on a first side of the anatomical structure. The end effector further includes a cartridge that is configured to house a plurality of staples. The cartridge has a first end, a second end, and a face that is positionable on a second side of the anatomical structure. A flexible member movably couples the first end of the cartridge to the first end of the anvil, and the second end of the cartridge is movably coupled to the second end of the anvil. Each of the anvil and the cartridge is insertable through a trocar into the patient. The end effector is remotely operable from outside the patient with at least a portion of one of the anvil and the cartridge being movable toward the other to clamp the end effector to the anatomical structure.

In one embodiment, the flexible member movably couples the second end of the anvil to the second end of the cartridge.

In one embodiment, at least one of the anvil and the cartridge slidably receives the flexible member when the end effector is clamped onto the anatomical structure.

In one embodiment, the anvil and the cartridge slidably receive the flexible member.

In one embodiment, the flexible member is anchored to the anvil.

In one embodiment, the flexible member is anchored to the cartridge.

In one embodiment, the end effector includes a tensioning device operable by the surgeon for selectively tensioning the flexible member to provide at least a portion of the clamping force on the anatomical structure. In one embodiment, the tensioning device includes a spring operably coupled to the flexible member.

In one embodiment, the first end or the second end of the cartridge includes a cam tube.

In one embodiment, the flexible member passes into the cam tube such that tensioning the flexible member pulls the anvil into the cam tube.

In one embodiment, the cam tube includes a first arcuate surface and the anvil includes a second arcuate surface that is configured to cooperate with the first arcuate surface.

In one embodiment, the anvil includes at least one pin and the cam tube includes at least one channel to receive the at least one pin to facilitate alignment between the anvil and the cartridge when the anvil enters the cam tube.

In one embodiment, the anvil includes a lever and the cam tube includes a slot to receive the lever to facilitate alignment between the anvil and the cartridge when the anvil enters the cam tube.

In one embodiment, the cam tube is slidable along an axis that is generally parallel to the longitudinal axis of the cartridge.

In one embodiment, the cam tube includes a wedge-shaped surface and the anvil includes a tapered surface on one end thereof that engages the wedge-shaped surface when the anvil enters the cam tube.

In one embodiment, the end effector further includes a screw and the cam tube is operably coupled to the screw. Rotating the screw moves the cam tube along a longitudinal axis of the cartridge.

In one embodiment, when the cam tube moves along a longitudinal axis of the cartridge, a gap between the anvil and the cartridge changes.

In one embodiment, the flexible member extends in a non-linear path from proximate the first end to proximate the second end of one of the anvil and the cartridge.

In one embodiment, the end effector further includes a strut mechanism that slidably cooperates with the flexible member and that includes a strut member that is coupled to one of the anvil and the cartridge between the first end and the second end thereof and is pivotal with respect thereto between a disengaged position in which the strut member is substantially parallel with the anvil and the cartridge and an engaged position in which the strut member extends transversely to the anvil and the cartridge.

In one embodiment, the manipulator includes an adjustment mechanism configured to adjust a gap between the anvil and the cartridge. In one embodiment, the adjustment mechanism includes a knob and a spring in line with at least one end of the flexible member.

In one embodiment, one of the anvil and the cartridge includes at least one alignment pin extending outwardly from the face thereof and the other of the anvil and the cartridge includes a mating recess configured to receive the alignment pin as the anvil and cartridge are moved toward one another.

In one embodiment, the flexible member extends through the mating recess and is coupled to the alignment pin such that retraction of each flexible member moves the alignment pin into the recess.

In one embodiment, the end effector further includes a compression mechanism that operably couples the anvil to the cartridge, that is separate from the flexible member, and that is configured to apply compressive force to the anatomical structure.

In one embodiment, the compression mechanism includes a hook member that extends from the anvil, a pin that is engagable with the hook member, and a compression slide that carries the pin and is selectively slidable relative to the cartridge. The compression mechanism is engagable when the hook member is positioned to engage the pin and, when the compression slide is forcibly moved relative to the cartridge, the pin engages the hook member to compress the anatomical structure separate from the flexible member.

In one embodiment, the compression mechanism includes a wedge that extends from the anvil and a collar that is engagable with the wedge and is movable relative to the cartridge. The compression mechanism is engagable when the wedge is positioned to engage the collar, and when the collar is moved relative to the cartridge, the wedge engages the collar to compress the anatomical structure separate from the flexible member.

In one embodiment, the compression mechanism further includes a second wedge that extends from the anvil and a cam tube that is engagable with the second wedge and is movable relative to the cartridge. The compression mechanism is engagable when the second wedge is positioned to engage the cam tube, and when the cam tube is moved relative to the cartridge, the wedge engages the cam tube to compress the anatomical structure separate from the flexible member.

In one embodiment, at least one of the first end and the second end of the cartridge includes a cam tube.

In one embodiment, the first end of the cartridge includes a first cam tube and the second end of the cartridge includes a second cam tube.

In one embodiment, the first and second cam tubes are configured to move along a longitudinal axis of the cartridge, and when at least one of the first and second cam tubes moves, a gap between the anvil and the cartridge changes.

In one embodiment, the end effector includes an alignment mechanism configured to facilitate alignment between the anvil and the cartridge as the anvil is moved toward the cartridge. In one embodiment, the alignment mechanism includes a pin on one of the anvil and the cartridge and a recess on the other of the anvil and the cartridge.

In one embodiment, the alignment mechanism includes a knife that has a first flange, a second flange, and a web connecting the first and second flanges and including a cutting edge. A housing extends from the cartridge adjacent the first end, and the knife resides in the housing when the anvil and the cartridge are moved toward one another. A recess in the anvil is adjacent the first end of the end effector and receives the housing. A first slot in the anvil is open to the anvil face and to the recess and is configured to slidably receive the web during cutting of the anatomical structure with the cutting edge. A second slot in the cartridge is open to the cartridge face and is configured to slidably receive the web during cutting of the anatomical structure with the cutting edge.

In one embodiment, each of the first ends and the second ends of the anvil and the cartridge are movably coupled together by a hinge joint, a flexible member, a latch, or combinations thereof.

In one embodiment, the second end of the anvil is coupled to the second end of the cartridge by a hinge joint, a flexible member, a latch, or combination thereof.

In one embodiment, a hinge pivotally couples the first end of the anvil to the first end of the cartridge, and a flexible member movably couples the second end of the anvil to the second end of the cartridge.

In one embodiment, the end effector further includes a spring operably coupled to each of the anvil and the cartridge and biasing the anvil and the cartridge away from each other.

In one embodiment, one of the anvil and the cartridge further includes a stud at the second end, the flexible member configured to couple to the stud.

In one embodiment, the anvil and the cartridge are coupled by a snap fit connection at the first end.

In one embodiment, one of the anvil and the cartridge includes a hook on the first end, the other of the anvil and the cartridge includes a lever at the first end, and the hook is configured to engage the lever to couple the anvil and the cartridge at the first end.

In one embodiment, the end effector further includes a first flexible member that movably couples the first end of the anvil to the first end of the cartridge, and a second flexible member that movably couples the second end of the anvil to the second end of the cartridge.

In one embodiment, the first and second flexible members are independently operable such that a clamping force between the first ends is capable of being different from a clamping force between the second ends.

In one embodiment, the first and second flexible members are independently operable such that a gap between the first ends of the anvil and the cartridge is capable of being different from a gap between the second ends of the anvil and the cartridge.

In one embodiment, the anvil and the cartridge are coupled by a latch at one of the first and second ends and a flexible member at the other of the first and second ends.

In one embodiment, the latch is a projection from one of the anvil and the cartridge and the other of the anvil and the cartridge includes a recess configured to receive the latch.

In one embodiment, the latch includes a notch and the other of the anvil and the cartridge further includes a pin that projects into the recess and engages the notch when the latch enters the recess.

In one embodiment, the end effector further includes a spring that biases the pin into engagement with the notch.

In one embodiment, the end effector further includes a release cable coupled to the pin and operable to release the pin from the notch.

In one embodiment, the anvil and the cartridge are curved.

In one embodiment, the end effector is insertable through a trocar.

In one embodiment, an endocutter stapling device may be used by a surgeon to staple an anatomical structure of a patient during a minimally invasive surgical procedure. The endocutter stapling device may include the end effector, a manipulator, and a flexible member. The manipulator is configured to be accessible to the surgeon outside of the patient and includes a shaft coupled to the end effector and a clamping mechanism for selectively moving the anvil and the cartridge toward one another to clamp the anatomical structure. The flexible member extends through the shaft to the end effector and is operably coupled to at least one of the anvil and the cartridge and to the clamping mechanism such that operating the clamping mechanism withdraws the flexible member from the end effector and clamps the anatomical structure between the anvil and the cartridge.

In one embodiment, the clamping mechanism is capable of selectively tensioning the flexible member to clamp the anvil and the cartridge to the anatomical structure with a first stage clamping force that permits the end effector to be repositioned relative to the anatomical structure.

In one embodiment, the first stage clamping force is between about 0.1 g/mm2and about 4 g/mm2.

In one embodiment, the clamping mechanism is capable of selectively tensioning the flexible member to clamp the anvil and the cartridge to the anatomical structure with a second stage clamping force that substantially prevents the end effector from moving relative to the anatomical structure during the medical procedure.

In one embodiment, the second stage clamping force is between about 4 g/mm2and about 70 g/mm2.

In one embodiment, the manipulator includes a handpiece that at least partially houses the clamping mechanism. The clamping mechanism further includes a lever that is pivotable relative to the handpiece and is operable to activate the clamping mechanism. In one embodiment, the clamping mechanism includes a first push bar that is pivotably coupled to the lever, a second push bar that is pivotably coupled to the first push bar, and a pin that is coupled to the second push bar, the flexible member extending around the pin. Rotation of the lever relative to the handpiece moves the pin and withdraws the flexible member from the end effector.

In one embodiment, the clamping mechanism includes a hub that is pivotable relative to the handpiece with the lever extending from the hub, a torque arm that extends outwardly from the hub, a push bar that is pivotably coupled to the torque arm at a first end, a clamping rod that is pivotably coupled to the push bar at a second end and is slidably engaged with the handpiece, and two or more additional rods that are fixed in relation to the clamping rod with the clamping rod between at least two additional rods. The flexible member is in contact with the clamping rod and with two of the additional rods such that, when the clamping mechanism is engaged, the clamping rod slides relative to the at least two additional rods and withdraws the flexible member from the end effector.

In one embodiment, the manipulator further includes a locking mechanism for selectively locking the clamping mechanism in an engaged position in which the anvil and the cartridge clamp the anatomical structure.

In one embodiment, the locking mechanism includes a locking arm that extends from the hub, a release lever that is pivotably coupled relative to and that projects from the handpiece, and a locking finger that extends from the release lever and is biased into engagement with the locking arm. Rotation of the lever to engage the clamping mechanism engages the locking arm with the locking finger.

In one embodiment, the manipulator includes a stapling mechanism that has an actuator coupled to an actuator plate that is slidable relative to the end effector and at least one wedge coupled to the actuator plate, wherein activating the actuator slides the actuator plate and the at least one wedge in the direction of the end effector to force the wedge into engagement with staples.

In one embodiment, the actuator is a thumb plate.

In one embodiment, the actuator is a lever and the stapling mechanism further includes a chain consisting of a plurality of links coupled to the actuator plate. The lever is operably coupled to the chain such that rotation of the lever moves the chain and the actuator plate.

In one embodiment, the manipulator includes a cutting mechanism having a knife push bar that is slidably coupled to the actuator plate and a cutting edge at one end of the knife push bar. When the stapling mechanism is engaged, the actuator plate slides relative to the knife push bar for a predetermined distance during which the knife push bar is substantially stationary and after which the actuator plate engages the knife push bar.

In one embodiment, the wedge is engaged over the predetermined distance.

In one embodiment, the manipulator includes a cutting mechanism that is configured to cut the anatomical structure and is coupled to the actuator plate and, when the actuator is engaged, the stapling mechanism begins stapling the anatomical structure prior to the cutting mechanism cutting the anatomical structure.

In one embodiment, the end effector is pivotable relative to the shaft.

In one embodiment, the device further includes an articulation mechanism that includes a clevis and a rotation collar, the rotation collar frictionally coupling the end effector to the clevis.

In one embodiment, the device further includes a compression mechanism that operably couples the anvil to the cartridge, that is separate from the flexible member, and that is configured to apply compressive force to the anatomical structure. The compression mechanism includes a hook member that extends from the anvil, a pin that is engagable with the hook member, and a compression slide that carries the pin and is selectively slidable relative to the cartridge. The compression mechanism is engagable when the hook member is positioned to engage the pin and, when the compression slide is forcibly moved relative to the cartridge, the pin engages the hook member to compress the anatomical structure separate from the flexible member.

In one embodiment, the device further includes a compression mechanism that operably couples the anvil to the cartridge, that is separate from the flexible member, and that is configured to apply compressive force to the anatomical structure. The compression mechanism includes a wedge that extends from the anvil and a collar that is engagable with the wedge and is movable relative to the cartridge. The compression mechanism is engagable when the wedge is positioned to engage the collar, and when the collar is moved relative to the cartridge, the wedge engages the collar to compress the anatomical structure separate from the flexible member.

In one embodiment, a method of stapling an anatomical structure during a minimally invasive medical procedure includes inserting the end effector through a trocar into a patient adjacent the anatomical structure, positioning the anvil and the cartridge on opposing sides of the anatomical structure, clamping the end effector to the anatomical structure at a first end and a second end of the end effector to secure the position of the end effector relative to the anatomical structure, and actuating the end effector to staple the anatomical structure.

In one embodiment, a method of stapling an anatomical structure during a minimally invasive medical procedure includes inserting the cartridge of the end effector through a trocar into a patient adjacent the anatomical structure, inserting the anvil of the end effector of claim1through a trocar into a patient adjacent the anatomical structure, positioning the anvil and the cartridge on opposing sides of the anatomical structure, clamping the end effector to the anatomical structure at a first end and a second end of the end effector to secure the position of the end effector relative to the anatomical structure, and actuating the end effector to staple the anatomical structure.

In one embodiment, an end effector for use by a surgeon to staple an anatomical structure of a patient during a minimally invasive procedure, the anatomical structure having a first side, a second side, a proximal end, and a distal end, includes an anvil that includes a first end, a second end, and a face that is positionable on the first side of the anatomical structure. The first end of the anvil is configured to extend beyond one of the proximal end or the distal end, and the second end of the anvil being configured to extend beyond the other of the proximal end or the distal end. The end effector further includes a cartridge that is configured to house a plurality of staples and that includes a first end, a second end, and a face that is positionable on the second side of the anatomical structure. The first end of the cartridge is configured to extend beyond one of the proximal end or the distal end, and the second end of the cartridge is configured to extend beyond the other of the proximal end or the distal end. The first end of the cartridge is movably coupled to the first end of the anvil and the second end of the cartridge is movably coupled to the second end of the anvil. Each of the anvil and the cartridge is insertable through a trocar and the end effector is remotely operable from outside the patient with at least a portion of one of the anvil and the cartridge being movable toward the other to clamp the end effector on a targeted resection line from the proximal end to the distal end of the anatomical structure.

In one embodiment, a method of stapling an anatomical structure during a minimally invasive medical procedure includes inserting the end effector through a trocar into a patient adjacent the anatomical structure, positioning the anvil and the cartridge on opposing sides of the anatomical structure on a target resection line such that the first end of each of the anvil and the cartridge extends beyond a proximal end of the anatomical structure and the second end of each of the anvil and the cartridge extends beyond a distal end of the anatomical structure, clamping the end effector to the anatomical structure to secure the position of the end effector on the resection line, and actuating the end effector only a single time to staple the anatomical structure from the proximal end to the distal end along the target resection line.

In one embodiment, an end effector is coupled to a manipulator having a shaft. The end effector is for use by a surgeon to staple an anatomical structure of a patient during a minimally invasive procedure. The anatomical structure has a first side and a second side. The end effector includes an anvil and a cartridge. The anvil includes a first end, a second end, and a face that is positionable on the first side of the anatomical structure. The cartridge is configured to house a plurality of staples and includes a first end, a second end, and a face that is positionable on the second side of the anatomical structure. The end effector further includes a housing that extends from one end of the anvil or the cartridge and that includes a flange. The flange defines a longitudinal axis. The end effector further includes a clevis and a rotation collar. The clevis is coupled to the shaft and is operable to pivot relative to the shaft. The rotation collar is rotatably coupled to the flange and is coupled to the clevis. The flange is capable of rotating within the rotation collar. Each of the anvil, the cartridge, the housing, the clevis, and the rotation collar is insertable through a trocar. The end effector is rotatable about the longitudinal axis, is pivotable relative to the shaft at the clevis, and is remotely operable from outside the patient with at least a portion of one of the anvil and the cartridge being movable toward the other to clamp the end effector to the anatomical structure.

In one embodiment, the first end of the cartridge is movably coupled to the first end of the anvil and the second end of the cartridge is movably coupled to the second end of the anvil.

In one embodiment, the first end of the anvil is configured to extend beyond one of a proximal end or a distal end, and the second end of the anvil is configured to extend beyond the other of the proximal end or the distal end. The first end of the cartridge is configured to extend beyond one of the proximal end or the distal end, and the second end of the cartridge is configured to extend beyond the other of the proximal end or the distal end.

In one embodiment, the end effector is for use by a surgeon to staple an anatomical structure of a patient during a minimally invasive procedure, the anatomical structure having a first side and a second side. The end effector includes an anvil that includes a first end, a second end, and a face that is positionable on the first side of the anatomical structure. The end effector further includes a cartridge that is configured to house a plurality of staples and that includes a first end, a second end, and a face that is positionable on the second side of the anatomical structure. The first end of the cartridge is separably coupled to the first end of the anvil, and the second end of the cartridge is separably coupled to the second end of the anvil. Each of the anvil and the cartridge is insertable through a trocar, and the end effector is remotely operable from outside the patient with at least a portion of one of the anvil and the cartridge being movable toward the other to clamp the end effector to the anatomical structure.

In one embodiment, the first end of the cartridge includes a first cam tube and the second end of the cartridge includes a second cam tube.

In one embodiment, the first and second cam tubes are configured to move along a longitudinal axis of the cartridge, and when at least one of the first and second cam tubes moves, a gap between the anvil and the cartridge changes.

In one embodiment, the first and second cam tubes are configured to move along a longitudinal axis of the cartridge, and when at least one of the first and second cam tubes moves, a gap between the anvil and the cartridge changes.

In one embodiment, the anvil and the cartridge are coupled by a snap fit connection at the first end.

In one embodiment, one of the anvil and the cartridge includes a hook on the first end, the other of the anvil and the cartridge includes a lever at the first end, and the hook is configured to engage the lever to couple the anvil and the cartridge at the first end.

In one embodiment, the end effector further includes a flexible member that couples the first end of the anvil to the first end of the cartridge.

DETAILED DESCRIPTION

In its broadest aspects, embodiments of the present invention are directed to an end effector and/or an endocutter stapling device (collectively referred to as “devices” herein) for forming a resection line during resection of an organ, tissue, or other anatomical structure. The devices may be used during minimally invasive surgical procedures. As it is described herein, one or both of the devices may be used, for example, in a vertical sleeve gastrectomy procedure. It will be appreciated, however, that the devices may be used in other procedures involving other anatomical structures. For example, the devices may be used in a parencymal resection, lung volume reduction surgery, or other procedures involving the lung. Further, the devices may be useful in an anatomic resection, such as, a lobectomy, a non-anatomic parencymal resection, or other procedures involving the liver and in a partial nephrectomy, total nephrectomy, or other procedures involving the kidney.

To these and other ends, and with reference to the figures,FIG. 1illustrates the anatomy of the stomach10and a resection line12for a vertical sleeve gastrectomy. The stomach10generally includes a proximal end14, a distal end16, an anterior side18, and a posterior side20. The proximal end14and the distal end16of the stomach10are described from the perspective of the surgeon. A gastroesophageal junction22opens into the stomach10and is a common landmark in bariatric surgeries. A fundus24and the section of the stomach10defined by a greater curvature26are generally the parts of the stomach10removed during a vertical sleeve gastrectomy. The remaining pouch is generally defined by a lesser curvature28and the resection line12and presents a stomach with a significantly reduced volume. The desired location of the resection line12is about 0.5 cm to about 2 cm away from the gastroesophageal junction22and about 2 cm to about 10 cm away from a pylorus30. In accordance with aspects of the invention, endocutter stapling devices may be utilized to form high quality, consistent resection lines during a vertical sleeve gastrectomy. Embodiments of the devices are advantageous because they are easily positionable laparoscopically, accommodate different thicknesses of tissue along the resection line length, are capable of providing substantially uniform compressive pressure on the tissue along the resection line, and enable a low staple firing force.

With reference toFIG. 2A, embodiments of the present invention may include a shaft38to which is coupled an end effector40. The end effector40has two clamping members42,44coupled to one another. As is described below in reference toFIGS. 2B-2G, the surgeon may forcibly drive the members42,44toward one another to clamp an anatomical structure between the members42,44. The surgeon may close the members42,44remotely from the end effector40. That is, no direct manual access to the end effector40is required. For this reason, the end effectors, as disclosed herein, may be designed specifically for use in minimally invasive surgical procedures in which the anatomical structure or organ is accessed through a trocar. Clamping onto the anatomical structure permits the surgeon to be able to accurately position the end effector40and ensures creation of a straight sleeve gastrectomy pouch, which is desirable. In the exemplary embodiment, and with reference toFIG. 2B, the member42may be an anvil generally positionable on the anterior side18of the stomach10, and the member44may be a cartridge coupled directly to the shaft38and generally positionable on the posterior side20of the stomach10. As shown, the anvil42may be sufficiently long to extend beyond each of the proximal end14and the distal end16of the stomach10. The cartridge44may also be sufficiently long to extend beyond the proximal end14and the distal end16of the stomach10. The cartridge44may house a plurality of surgical staples and a knife, each described below, for forming the resection line12. The anvil42and the cartridge44are movably coupled together via a flexible member46and collectively operate as clamping members for purposes described below. While embodiment of the invention are not limited to movably coupling the anvil42to the cartridge44, as is described herein, by movably coupling the anvil42to the cartridge44, the anvil42has may directions in which it may move relative to the cartridge44. For example, the flexible member46may only restrict movement away from the cartridge44when the flexible member46is already taut. Otherwise, the flexible member46may allow relative movement in all other directions. The present invention is not limited to the illustrated arrangement. For example, the arrangement of the members42,44may be reversed such that the anvil42is coupled to the shaft38and is positioned adjacent the posterior side20of the stomach10and the cartridge44is coupled to the anvil42via the flexible member46and is positioned on the anterior side18of the stomach10(not shown). Other alternative arrangements may also be possible depending on the surgical procedure and the surgeon's preference, among other factors.

While the flexible member46is shown, the anvil42and the cartridge44may be coupled together at each end using a variety of engagement elements. For example, the anvil42and the cartridge44may be configured to connect using magnets, a clip-in connection, or other types of connections or connectors that are generally well known in the art. The connection method used at the proximal and distal ends of the anvil42and the cartridge44do not need to be similar. There are many ways to couple the anvil42and the cartridge44and the invention is not limited to the flexible member shown. By way of example, many of the connection methods described in PCT Application No. PCT/US2014/070869, which is incorporated by reference herein in its entirety, may be utilized to connect the anvil and the cartridge described herein.

In one embodiment, the surgeon may position the end effector40proximate the stomach10as is shown inFIG. 2B. In this regard,FIG. 2Billustrates the end effector40placed around the stomach10on a target resection line12with the anvil42and the cartridge44coupled together at both the proximal end14and the distal end16of the stomach10. By way of example, the anvil42and the cartridge44may be coupled to each other with the flexible member46at each of the proximal end14and the distal end16of the stomach10. The length of the anvil42and the cartridge44may be sufficient for the anvil42, the cartridge44, and the flexible member46to encircle the stomach10, as shown. The length of the anvil and/or the cartridge as described herein is not particularly limited. By way of example and not limitation, the length of each may measure from about 35 mm to about 350 mm. The end effector40may be put in place and used with or without having to mobilize the greater curvature26. For example, a surgeon may prefer to leave the greater curvature26attached to the omentum (not shown), which could improve stability of the stomach10during stapling.

As is described below, the flexible member46may be coupled to a tensioning mechanism by which the anvil42and the cartridge44may be moved toward one another and to provide a sufficient clamping force on the stomach10. In addition, the flexible member46may be coupled to a release mechanism that releases tension on the flexible member46and allows the anvil42to be separated from the cartridge44, such that the end effector40may be repositioned prior to stapling or after forming the resection line12. Further, the end effector40may be operably coupled to a stapling and/or cutting mechanism by which the surgeon may drive staples and a cutting element housed in the cartridge44, each of which is described below. In one embodiment where the ends of the anvil42and the cartridge44extend beyond the proximal and distal ends14,16of the stomach10, the end effector40may be advantageously configured to complete the staple line12after actuating the stapling and/or cutting mechanisms only a single time. This is in contrast to current procedures that require repeated activation of the stapling and/or cutting mechanisms.

In one aspect of the invention, the end effector40may be positioned relative to the stomach10using a two-stage clamping process. In the first clamping stage, the anvil42and the cartridge44may be clamped onto the stomach10to provide a threshold amount of resistance to unintentional movement of the end effector40relative to the stomach10. For example, the range of clamping pressure in the first stage may be about 0.1 g/mm2to about 4 g/mm2. While preventing undesirable or unintentional movements of the end effector40, the surgeon may move the end effector40to a desired position relative to the stomach10without significant difficulty.

In the second clamping stage, and with the end effector40in the desired location relative to the stomach10, the clamping force of the end effector40may be increased to effectively prevent or minimize the end effector40from moving relative to the stomach10. For example, the clamping pressure in the second stage may be about 4 g/mm2to about 70 g/mm2. In an exemplary embodiment, the clamping pressure in the second stage may be about 8 g/mm2. The upper limit to which the end effector40may be clamped is selected so as to avoid any damage to the underlying tissue being clamped but also allow for adequate tissue compression for staple formation. This upper limit may be, for example, about 70 g/mm2. Additionally, the lower limit in the disclosed range of about 4 g/mm2represents a threshold clamping force below which constitutes the first stage clamping and above which constitutes the second stage clamping. It will be recognized that these values are merely exemplary and the particular values may depend on several factors, including the anatomical structure being clamped. Thus, embodiments of the invention are not limited to the range of values provided herein.

In an advantageous aspect of the invention, when the end effector40is placed on the stomach10(e.g., in the first clamping stage as described above), the surgeon has a clear visualization of the intended results of the vertical sleeve gastrectomy prior to actually performing the resection of the stomach10at the resection line12. Hence, the surgeon has an indication of what the resultant stomach shape and volume defined by the lesser curvature28and the resection line12will likely be prior to stapling and/or cutting the stomach tissue. If the surgeon is not satisfied with the indication of the expected stomach shape and volume, the surgeon may adjust and manipulate the location and alignment of the end effector40prior to stapling and cutting the stomach10. This is in contrast to current procedures, where the resection line is generally not well visualized prior to activating the stapler, thus the ultimate outcome is less certain. It will be appreciated that the end effector40should be positioned such that it does not provide lateral stretching or tension of the stomach10, which may create an undesirable environment for stapling and cutting. Using the end effector40ensures proper alignment of the resection line12so that removing the fundus24occurs at a safe distance away from both the lesser curvature28and the gastroesophageal junction22. The result is a resection line12that is squared off at the fundus24of the stomach10to prevent or reduce the likelihood of necrotic tissue development.

Once the end effector40is properly positioned, as is shown inFIG. 2B, the surgeon may then engage the tensioning mechanism, described below, to compress the anvil42and the cartridge44on the stomach10, as is shown by the arrow50inFIG. 2B. In this regard, the end effector40may be coupled to a device for tensioning the flexible member46to draw the anvil42and the cartridge44onto the stomach10. As the anvil42and the cartridge44are brought together, the flexible member46may align one with the other. In this regard, the end effectors disclosed herein may be self-aligning due, in part, to coupling of the anvil42to the cartridge44at each end. Tensioning the flexible member46may also compress the tissue. For instance, as the flexible member46is tensioned, the distance between the anvil42and the cartridge44decreases, and ultimately compresses the stomach10. Once positioned and the anvil42and the cartridge44are compressed, the surgeon may activate a cutting and stapling mechanism, described below, to cut and staple the tissue using the end effector40until complete resection of the stomach10occurs, as is illustrated in the sequence ofFIGS. 2C, 2D, and 2E.

As noted above, the end effector40may be secured to the stomach10so that it resists movement once the surgeon begins stapling. As illustrated inFIGS. 2A-2E, the use of the end effector40aids in creating an ideal gastric sleeve pouch size and shape (e.g., shown inFIG. 2E). In one embodiment, the surgeon may engage a release mechanism after completing the resection of the stomach10. This allows slack to be introduced in the flexible member46such that the anvil42may be separated from the cartridge44. Consequently, once the anvil42and the cartridge44are separated, the end effector40may be removed from the abdominal cavity.

In embodiments of the present invention that include a flexible member for tensioning the anvil and the cartridge, the flexible member may take several forms. By way of example and without limitation, the flexible member may include a wire, suture, thread, chain, or other elongate flexible member. The flexible member may be made of metal, plastic, or any other material that is suitable for a biological environment. The flexible member may be, for example, a braided cable. The flexible member may be capable of a radius of bend of approximately 0.030 inches and further be generally resistant to kinking, knotting, etc. Additionally, the flexible member should be able to accommodate a tensile load sufficient to generate a clamping force (pressure) above the maximum clamping force expected to be imposed during a procedure. By way of example, the flexible member should be able to accommodate a tensile load sufficient to create a clamping force of about 70 g/mm2on the anatomical structure. In an exemplary embodiment, the flexible member may be a multi-strand stainless steel cable or a polymer, such as vectran.

As illustrated inFIG. 2A, the end effector40may be pre-assembled and then inserted into the abdominal cavity as a unit. In this regard, and with reference toFIG. 2B, using standard laparoscopic instruments and graspers, the surgeon may manipulate the end effector40across the stomach10so that the anvil42is generally positioned along the anterior side18of the stomach10and the cartridge44is generally positioned along the posterior side20of the stomach10. A distal end42aof the anvil42generally extends beyond the distal end16of the stomach10. A distal end44aof the cartridge44may also generally extend beyond the distal end16of the stomach10. A similar configuration exists at the opposite end. Proximal ends42b,44bof the anvil42and the cartridge44, respectively, generally extend beyond the proximal end14of the stomach10. The section of the flexible member46between the anvil42and the cartridge44may loop or extend around the distal end16of the stomach10, as illustrated inFIG. 2B. The anvil42and the cartridge44may then be manipulated to provide a clamping force on the stomach10. This clamping may be achieved by tensioning the flexible member46, as is described below.

As an alternative to pre-assembling the end effector40externally, the end effector40may be assembled inside the abdominal cavity. In this regard, and with reference toFIGS. 2F and 2Gand in one embodiment, the flexible member46may be inserted through a trocar (not shown). Using laparoscopic instruments and graspers, the surgeon may manipulate the flexible member46around the stomach10, as shown inFIG. 2F. Through the same or another trocar, the surgeon may then insert the member42and/or the member44. Each of the members42,44may be engaged with the flexible member46and with the shaft38. The surgeon may then perform the procedure.

Another method for partial external assembly is shown inFIGS. 2H-2K, in which the surgeon may use two trocars to assemble and manipulate the end effector40to perform a procedure. With reference toFIG. 2H, the surgeon may manipulate the cartridge44with the shaft38through a first trocar54and insert a pair of graspers56through a second trocar58. The shaft38may be coupled to the cartridge44via a ball joint to aid in the proper placement of the cartridge44. InFIG. 2I, the surgeon may use the graspers56to grip a retraction tab60that is coupled to the flexible member46and pull the retraction tab60and, consequently, the flexible member46through the second trocar58. As is shown inFIG. 2H, the retraction tab60extends from the cartridge44. With reference toFIG. 2J, the surgeon may couple the anvil42to the flexible member46outside of the abdominal cavity and then slide the anvil42through the second trocar58. The end effector40may initially be disarticulated so that the surgeon may retract the flexible member46to draw the anvil42proximate the stomach10and then secure the flexible member46to the cartridge44. That is, the anvil42may be a separable member that is coupled to the other components such that the anvil42is movably coupled to the cartridge44, as is described above. Once assembled, as is shown inFIG. 2K, the surgeon may perform the procedure with the end effector40.

With reference toFIGS. 2L and 2M, another method for assembling an end effector is shown. In that regard, the anvil42may be coupled to a manipulation shaft62, such as, by a ball joint. The manipulation shaft62may be maneuvered through the second trocar58to align and movably couple the anvil42to the cartridge44. The anvil42may be a separable member in this embodiment that is coupled to the other components such that the anvil42is movably coupled to the cartridge44. By way of example only, the anvil42may be coupled to the cartridge44with a latch at one end and the flexible member at the other end, though other connection methods may be utilized. Alternative connection methods may include latches at each end of the end effector or magnets that assist the surgeon in alignment of the members42,44. Another alternative connection is shown inFIG. 2N. As shown, the members42,44may be coupled together at a snap fit connection64a,64bwith a ball joint66. The anvil42and cartridge44may be inserted through separate trocars and assembled intra-abdominally. The anvil42may be introduced to the abdominal cavity and coupled to the cartridge44by an externally controlled instrument62. The snap fit connection may separably couple the anvil42to the cartridge, though in the absence of a flexible member. As yet another alternative (not shown), one of the cartridge or the anvil may include a flexible member in the form of a loop and having a pull tab positioned to be withdrawn from the abdominal cavity so that the other of the cartridge and the anvil may be coupled to the flexible member.

With reference toFIGS. 3-16, the surgeon may operate the end effector40above, including one or both of the anvil42and the cartridge44, during a vertical sleeve gastrectomy procedure with another mechanical device that is operably coupled to the one or both of the anvil42and the cartridge44. In one embodiment, an endocutter stapling device100includes the end effector40operatively coupled to a manipulator102. As shown, the manipulator102includes an elongate member or shaft104coupled to a handpiece106at one end and the end effector40at the other end thereof. During a surgical procedure, the end effector40and a portion of the shaft104may be inserted into the patient, such as via a trocar. The surgeon may then manipulate the end effector40and/or articulate the end effector40relative to the manipulator102to perform a procedure. Thus, embodiments of the present invention may include mechanisms for effectuating a surgical procedure with the end effector40(including clamping, stapling, and cutting tissue) and for allowing the end effector40to articulate relative to the shaft104, each described below.

With reference toFIGS. 3, 4, and 4A, the anvil42and the cartridge44are movably coupled together via the flexible member46as is described above. The flexible member46passes through hollow portions of the anvil42and the cartridge44and is movable relative to one or both of the anvil42and the cartridge44. The flexible member46may be anchored to one of the anvil42or the cartridge44, as is described below. In the exemplary embodiment shown, the anvil42may be separated from or brought closer to the cartridge44by extending or retracting the flexible member46. Retraction of the flexible member46moves the anvil42toward the cartridge44as is shown generally by arrow52inFIG. 4A.

In this regard, in the exemplary embodiment shown inFIGS. 4-6, the flexible member46extends from the shaft104into the cartridge44at a proximal end44band ultimately couples the anvil42to the cartridge44. While numerous pathways for the flexible member46are described below with reference to at leastFIGS. 21-35, in the exemplary embodiment, the flexible member46passes from the cartridge44and is coupled to the anvil42adjacent each of a distal end42aand a proximal end42bthereof and may be anchored within the anvil42by anchors110and112(shown inFIG. 6).

Retraction of the flexible member46from the end effector40(and into the manipulator102described below) therefore moves at least one of the anvil42and/or the cartridge44as is shown generally by the arrow52inFIG. 6. It will be appreciated that because the flexible member46is anchored to the anvil42(e.g., proximate each of the distal end42aand the proximal end42b), retraction of the flexible member46produces a substantially symmetrical closing force on tissue situated between the anvil42and the cartridge44. This configuration, with connectivity between the anvil42and the cartridge44at each end of the end effector40, is advantageous.

In this regard, in embodiments in which the anvil42and/or the cartridge44are sufficiently rigid at pressures encountered during a surgical procedure, the clamping force may be more symmetrical and uniformly distributed along the length of the anvil42and the cartridge44. Thus, the tissue situated between the anvil42and the cartridge44may be more uniformly compressed. It will be appreciated that even though there may be more uniform compression on the tissue, the anvil42and the cartridge44may not be parallel to one another in the clamped position because the tissue may not be uniformly thick. Nevertheless, there may be uniformity in applied pressure. This may be unlike prior art devices in which clamping members are attached together at a single, hinge-like location and have a jaw-like motion, rather than a vice-like motion. With a single connection, the end of the clamp member most distant from the connection may deflect. As a result of the deflection, the clamp member may not apply uniform, symmetrical compression to the tissue along its length. According to embodiments of the invention, producing a substantially uniformly applied clamping pressure on the organ may enhance the formation of the resection line following stapling and cutting.

With reference toFIGS. 3, 4, 5, and 6, in one embodiment, the handpiece106includes a main body114with housing halves120a,120b. When assembled, the housing halves120a,120benclose control features by which the surgeon may operate clamping of the anvil42and the cartridge44on tissue and stapling and cutting of the stomach10. In that regard, the manipulator102includes a clamping mechanism122for applying tension to the flexible member46, a stapling mechanism124for stapling the tissue captured between the anvil42and the cartridge44, and a cutting mechanism126for cutting the tissue. Each of these mechanisms is described below. Thus, in one aspect, the surgeon may operate the clamping mechanism122to control the extension and retraction of the flexible member46from the end effector40. In another aspect, the surgeon may actuate the stapling mechanism124to fire staples and actuate the cutting mechanism126to cut tissue.

To these and other ends, with continued reference toFIG. 5, the manipulator102includes a support130having a U-shaped cross-section coupled to the end effector40at a proximal end. A guide beam136of about the same length as the support130reinforces the support130and may include three channels138a,138b, and140that may receive portions of each of the stapling mechanism124, the cutting mechanism126, and the clamping mechanism122. While each of these mechanisms is described herein with respect to one or more embodiments, embodiments of the present invention may omit the cutting mechanism126, in which case, the device may be referred to as a stapling device.

In the embodiment shown, the manipulator102further includes a frame150having a shaft portion152and a handpiece portion154. The shaft portion152may have a tubular configuration, for example, a right circular tubular configuration and may enclose the support130and the guide beam136when the manipulator102is assembled. The support130may be configured to receive a pin142that cooperates with a corresponding bore144in the shaft portion152to secure the support to the frame150.

The handpiece portion154of the frame150includes opposing flanges156a,156bdefining a channel158. Each of the flanges156a,156bincludes one or more slots that guide a portion of the clamping mechanism122, described below. In the embodiment shown, each flange156a,156bincludes two pairs of slots160a,160b,162a,162b. The pair of slots160a,162aon the flange156ais a mirror image of the pair of slots160b,162bon the flange156b. As shown, each of the slots160a,160bis elongated in a direction generally parallel with the longitudinal axis of the manipulator102. The slots162a,162bare also elongated but are angled with respect to the longitudinal axis of manipulator102and angled relative to the slots160a,160b.

The clamping mechanism122includes a lever170pivotably coupled between the housing halves120a,120bfor manipulating the flexible member46. With reference toFIGS. 6 and 7, the surgeon may squeeze the lever170by which motion the flexible member46is withdrawn from the end effector40. As is described above, withdrawing or pulling the flexible member46from the end effector40draws the anvil42toward the cartridge44and may tension the flexible member46when the anvil42and the cartridge44meet resistance to movement. By applying a force to the flexible member46, the anvil42and the cartridge44may be moved toward one another (as is indicated by arrow52) and may also apply a clamping force to tissue situated between the anvil42and the cartridge44. It will be appreciated that the surgeon may operate the lever170with one or more fingers during operation of the endocutter stapling device100between a disengaged position (e.g.,FIGS. 3 and 6) in which the clamping mechanism122does not restrict movement of the flexible member46and an engaged position (e.g.,FIGS. 4 and 7) in which the clamping mechanism122contacts the flexible member46.

To that end, the clamping mechanism122further includes a push bar164pivotably coupled to the lever170by a pin166at one end thereof. The push bar164extends from outside the housing half120a, where it is pivotally attached to the lever170by the pin166, into the channel158through a slot (unlabeled) in the handpiece portion154of the frame150. The push bar164is pivotally coupled to a push bar174by a pin172. The pin172extends through the push bar164at one end thereof across the channel158and is slidably received in each of the slots160a,160b(FIG. 5). The push bar174is coupled to a second pin176at the opposing end of the bar174from the pin172. The pin176is slidably received in each of the slots162a,162b(FIG. 5). The pins172and176interact with the flexible member46when the surgeon squeezes the lever170. By way of example only, and not limitation, one or both of the pins172and176may be coupled to a sheave (not shown), which slidably receives the flexible member46, to guide the flexible member46during motion of the clamping mechanism122.

With continued reference toFIG. 6, the flexible member46extends between the flanges156a,156band is looped over the pin172and the pin176(e.g., in sheaves on each pin172,176). In the exemplary embodiment, an additional pin178may extend across the channel158in fixed relation to the frame150. The pin178may be positioned at a location that maintains the flexible member46in alignment with the shaft104. In other words, the pin178may be configured to align the flexible member46with the shaft104independent of the position of the pins172,176as the pins172,176slide in relation to the slots160a,160b,162a,162b. Thus, while the flexible member46may move in response to actuation of the clamping mechanism122along each of the pins172,176, the additional pin178may maintain alignment of the flexible member46with the longitudinal axis of the manipulator102.

With reference toFIGS. 6 and 6A, depression of the clamping lever170toward the housing half120ain the direction of the arrow180inFIG. 6may cause movement of each of the push bars164,174generally away from the end effector40in the direction of the longitudinal axis of the handpiece106. Specifically, as is shown inFIG. 6, the push bars164,174initially have a generally L-shaped arrangement when the lever170is extended from the handpiece106. In this disengaged position of the lever170, the anvil42is spaced apart from the cartridge44, as is shown inFIGS. 6 and 6A. As the lever170is compressed towards the handpiece106(according to the arrow180), the push bar164pushes the pin172along the slots160a,160b(according to the arrow184). This movement also simultaneously forces the push bar174along the longitudinal axis of the manipulator102as guided by the pin172in the slots162a,162b(according to the arrow186). The pins172,176carry the flexible member46in the same direction away from the end effector40. Overall, the flexible member46is withdrawn from the end effector40resulting in movement of the anvil42toward the cartridge44.

Compression of the lever170into the engaged position results in the configuration of the endocutter stapling device100shown inFIGS. 7 and 7A, in which the push bars164,174are generally aligned with respect to one another and the anvil42and cartridge44are compressed onto the stomach10. In the generally aligned configuration between the push bars164,174, the path around which the flexible member46extends is lengthened relative to the L-shaped arrangement shown inFIG. 6. By lengthening the path, the flexible member46is carried rearwardly within the handpiece106during actuation of lever170. This results in a corresponding withdrawal of the flexible member46from the end effector40. Accordingly, the compression of the lever170toward the housing half120apulls the anvil42towards the cartridge44as is indicated by arrow52inFIG. 7. This motion may result in compression of the stomach10between the anvil42and the cartridge44, as is shown inFIG. 7A. In one embodiment, the surgeon may use a variable gripping force on the lever170to effectuate the first stage of compression. In this regard, the surgeon may approximate a first stage gripping force on the clamping mechanism122where the tissue is still slidable between the anvil42and the cartridge44. This is useful in positioning the end effector around an anatomical structure, such as the stomach, where both anterior and posterior halves of the anatomical structure must be managed. This is especially useful in a procedure such as a sleeve gastrectomy where the surgeon desires to create the resultant stomach pouch using equal amounts of anterior and posterior stomach. By way of example and not limitation, the clamping mechanism122may be capable of tensioning the flexible member46to about 200 lb at each end of the anvil42. This may provide a clamping pressure of over 100 psi. Specifically, in an exemplary embodiment, the anvil42and the cartridge44may have a length of about 250 mm and a width of about 10 mm providing a surface area of about 25 cm2. With 400 lb of total tension on the flexible member46(i.e., 200 lb on each side), the total compression pressure may be about 103 psi. At these pressures, the clamping mechanism122squeezes tissue fluid out of the stomach and thereby approves staple line integrity.

With reference now toFIG. 6A, in one embodiment, the anvil42includes a plurality of staple pockets190along a face192of the anvil42. The cartridge44includes a face194that opposes the face192of the anvil42. Each of the faces192,194is configured to sandwich the stomach10therebetween. A cartridge body196may at least partially enclose the cartridge44. The staple pockets190in the face192generally align and correspond to a plurality of staples198and a plurality of staple drivers200that are housed in a plurality of staple channels206in the cartridge44. The staples198are configured to be forced through the stomach10and be deformed by the staple pockets190. It will be appreciated that deforming the staples198into a B-shaped configuration secures opposing sides of the stomach10together.

In one embodiment, to facilitate alignment between the anvil42and the cartridge44, and in particular, alignment between the staples198and the staple pockets190, an alignment pin202may extend beyond the face192at the distal end42aof the anvil42or the face194at the distal end44aof the cartridge44. The other face192,194of the anvil42or the cartridge44includes a mating recess204. Once the lever170is compressed, the flexible member46is pulled into the handpiece106by the clamping mechanism122as described above. This motion pulls the anvil42toward the cartridge44and the alignment pin202in conjunction with the recess204to facilitate proper alignment between the anvil42and the cartridge44to align the staples198with a corresponding pocket190. With reference toFIG. 7A, the anvil42and the cartridge44are shown to compress the stomach10between the face192of the anvil42and the face194of the cartridge44with the alignment pin202being received in the mating recess204. In another aspect of the present invention, once the lever170is compressed, as is shown inFIG. 7, with the anvil42and the cartridge44compressing the stomach10therebetween, the surgeon may staple and cut the stomach10along the resection line12(FIG. 1). To staple the stomach10, the surgeon activates the stapling mechanism124.

In that regard and with reference toFIGS. 3, 8, and 9, the stapling mechanism124includes a staple actuator210having a thumb tab212. The staple actuator210further includes an actuator plate214that is coupled to the thumb tab212. The actuator plate214is slidably received in a slot218(FIG. 3) formed between the housing halves120a,120band is movable relative to the handpiece106as is indicated by the arrow232inFIGS. 8 and 9. The actuator plate214includes slots222a,222bspaced apart from an elongated slot224. In the embodiment shown, the slots222a,222beach receive a wedge push bar226a,226b, respectively. As is shown inFIGS. 5 and 10, the wedge push bars226a,226bare elongated members that extend generally along the length of the handpiece106and through the shaft104and terminate proximate the end effector40. The wedge push bars226a,226bare slidably received in corresponding channels138a,138bof the guide beam136and are positioned to slide into engagement with the staples198and the staple drivers200in the cartridge44.

In one embodiment, shown inFIGS. 10 and 11, each wedge push bar226a,226bterminates in a wedge tip230a,230bwhich, prior to activation of the stapling mechanism124, is positioned to engage respective rows of the staple drivers200in the cartridge44. The wedge tips230a,230bhave a wedge-shaped configuration and, during a sliding motion through the end effector40, are configured to force the staple drivers200toward the anvil42and drive the corresponding staples198through the compressed stomach10and into contact with the corresponding staple pockets190of the anvil42. As shown best inFIGS. 11 and 12, the shape of the wedge tips230a,230bforces the staples198into contact with the staple pockets190of the anvil42with sufficient force to deform the staples198and produce a B-shaped staple.

In one embodiment, the surgeon activates the stapling mechanism124by pushing the thumb tab212in the direction of the end effector40as is indicated by the arrow232inFIGS. 8 and 9. Pushing the thumb tab212slides each of the wedge push bars226a,226band the corresponding wedge tips230a,230bin the direction of the end effector40. Specifically, and with reference now toFIGS. 10-14, pushing the thumb tab212(FIG. 8) moves the wedge push bars226a,226bin the direction of the arrow234. The wedge tip230aengages the staple drivers200in sequence and thereby forces the staples198into the corresponding staple pockets190on the anvil face192as is indicated by the arrows238.

In another aspect of the present invention, the surgeon may cut the stomach10along the resection line12following stapling, described above. In one embodiment and with reference toFIG. 5, to cut the stomach10, the surgeon activates the cutting mechanism126. The cutting mechanism126includes a knife actuator248including the thumb tab212coupled to the actuator plate214. As described above and with reference toFIGS. 8 and 9, the actuator plate214is slidably received in the slot218formed between the housing halves120a,120band is movable relative to the handpiece106in a direction that is indicated by the arrow232inFIGS. 8 and 9.

With reference toFIGS. 8-14, in one embodiment, the cutting mechanism126includes the elongated slot224in the actuator plate214. A knife push bar250is slidably engaged in the elongated slot224and may be an elongated member extending from the actuator plate214through the handpiece106and the shaft104to a location adjacent the end effector40. In that regard, the knife push bar250is slidably received in the channel140of the guide beam136and terminates in a cutting edge252proximate the end effector40(shown best inFIGS. 11 and 12). As can be appreciated byFIGS. 5, 13, and 14, the knife push bar250lies in between the wedge push bars226a,226b.

In one embodiment, the surgeon activates the cutting mechanism126by pushing the thumb tab212in the direction of the end effector40as is indicated by the arrow232inFIGS. 8 and 10. Pushing the thumb tab212slides the knife push bar250via the actuator plate214and pushes the corresponding cutting edge252in the direction of the end effector40. Specifically, and with reference now toFIGS. 10-12, pushing the thumb tab212moves the cutting edge252in the direction of the arrow254(FIG. 11) along the longitudinal axis of the endocutter stapling device100. Although not shown, the cutting edge252cuts the stomach that may be sandwiched between the anvil42and the cartridge44.

In one embodiment, and with reference toFIGS. 8 and 9, the thumb tab212may activate each of the stapling mechanism124and the cutting mechanism126. As is described above, the actuator plate214captures each of the wedge push bars226a,226band the knife push bar250in slots222a,222band elongated slot224, respectively. In one embodiment, even though the actuator plate214is operably coupled to each of the wedge push bars226a,226band the knife push bar250, engagement of the stapling mechanism124occurs prior to actuation of the cutting mechanism126. In other words, the stapling mechanism124engages prior to engagement of the cutting mechanism126. The elongated slot224in the actuator plate214is oversized relative to the portion of the knife push bar250that is engaged with it. This configuration results in sliding space between the slot224and the knife push bar250. The knife push bar250therefore slides relative to the actuator plate214during initial movement of the plate214. The length of the movement of the actuator plate214without movement of the knife push bar250is predetermined.

The elongated slot224is also longer than each of the slots222a,222b. Because the knife push bar250is slidably received in the elongated slot224, the initial movement of the actuator plate214in the direction of arrow232inFIG. 8causes each of the wedge push bars226a,226bto move in direct relation to the movement of the actuator plate214. The movement of the knife push bar250is however delayed relative to the movement of the wedge push bars226a,226b. This means that there is a delay between activation of the stapling mechanism124and the cutting mechanism126. This delay is proportional to the free sliding space between the elongated slot224and the knife push bar250. When the surgeon pushes the thumb tab212in the direction of the arrow232inFIG. 8, the actuator plate214moves in the same direction and carries the wedge push bars226aand226bwith it. The knife push bar250does not initially move. Instead, the actuator plate214must move a predetermined distance corresponding to the free sliding space in the direction of the end effector40before the actuator plate214engages the knife push bar250. This is shown by way of comparison betweenFIGS. 8 and 9. InFIG. 8, the actuator plate214has not engaged the knife push bar250. InFIG. 9, the actuator plate214has moved a distance at least equivalent to the free sliding space and so the actuator plate214engages the knife push bar250. This delay in movement between the wedge push bars226a,226band the knife push bar250results in a difference in activation time between the stapling mechanism124and the cutting mechanism126. In this manner, in one embodiment, activation of the stapling mechanism124precedes activation of the cutting mechanism126.

Once the surgeon activates each of the stapling mechanism124and the cutting mechanism126by pushing on the thumb tab212, stapling and cutting may occur substantially simultaneously. By way of example only, the stapling of the stomach10may precede the cutting of the stomach10. That is, after an initial delay between stapling and cutting, during which the stapling mechanism124is activated, both of the stapling mechanism124and the cutting mechanism126are active. The surgeon may continue stapling and cutting the stomach10by continuing to push on the thumb tab212until the thumb tab212reaches the end of its stroke. It will be appreciated that the stroke of the thumb tab212may be greater than the overall length of the stomach10. Further, the stroke of the thumb tab212may be approximately equal to the length of the end effector40. At this point, the wedge tip230a,230bmay be proximate the distal end42a,44aof the end effector40. The end effector40and the shaft104may then be removed from the abdominal cavity with the stomach10having the configuration shown in, for example,FIG. 2E.

While embodiments of the present invention are shown and described as cutting the stomach10, embodiments of the present invention are not limited to those that both cut and staple the stomach. It may be preferable to staple without cutting in some instances. Accordingly, the staple line may be applied to the whole stomach or only a portion thereof without cutting the stomach. Resection may be performed with a separate device, such as, with a tissue welding device (e.g., a bipolar vessel sealing and cutting device). In this situation, the end effector40may remain clamped to the stomach10while the surgeon uses the separate device. The end effector40may be used to guide the separate device during resection.

In one embodiment and with reference now toFIGS. 15-19in which like reference numerals refer to like elements inFIGS. 3-14, the surgeon may operate the end effector40above, including one or both of the anvil42and the cartridge44, during a vertical sleeve gastrectomy procedure with an endocutter stapling device300that includes the end effector40operatively coupled to a manipulator302. As shown, the manipulator302includes an elongate member or shaft304coupled to a handpiece306at one end and the end effector40at the other end thereof. During a surgical procedure, the end effector40and a portion of the shaft304may be inserted into an abdominal cavity of the patient, such as, via a trocar. The surgeon may then manipulate the end effector40and/or articulate the end effector40relative to the manipulator302to perform a procedure. As described above, the procedure may include clamping, stapling, and cutting a stomach or other tissue. Thus, embodiments of the present invention may include mechanisms to effectuate a surgical procedure with the end effector40and may allow the end effector40to articulate relative to the shaft304.

With reference toFIGS. 15 and 16, the anvil42and the cartridge44of the end effector40are movably coupled together via the flexible member46similar to that described above and further below. In one embodiment, the manipulator302includes a main body308having housing halves310aand310bwhich produce a pistol-grip like handle. When assembled, the housing halves310a,310benclose control features by which the surgeon may operate the end effector40to perform the medical procedure. For example, the surgeon may open and close the anvil42and the cartridge44and staple and/or cut the stomach10.

In that regard, the manipulator302includes a clamping mechanism320for applying tension to the flexible member46, a stapling mechanism322for stapling the tissue captured between the anvil42and the cartridge44, and a cutting mechanism324for cutting the tissue captured between the anvil42and the cartridge44. Further, the main body308may include a locking mechanism326for locking the clamping mechanism320in an engaged position. Each of these mechanisms is described below. Thus, according to one aspect, the surgeon may operate the clamping mechanism320to control the retraction of the flexible member46from the end effector40and lock the end effector40in an engaged position, and according to another aspect, the surgeon may actuate the stapling mechanism322to fire staples and actuate the cutting mechanism324to cut tissue, as is described below.

To those and other ends, in one embodiment and with reference toFIG. 16, the manipulator302includes a support330having a U-shaped cross-sectional channel that is coupled to the end effector40at a proximal end. The support330may include a pair of bores352through a pair of tabs at a proximal end thereof. A guide beam332of about the same length as the support330reinforces the support330and may include three longitudinally extending channels336a,336b, and340that may receive portions of each of the stapling mechanism322, the cutting mechanism324, and the clamping mechanism320.

The manipulator302further includes a frame346having a shaft portion348and a handpiece portion350. The shaft portion348may have a tubular configuration, for example, a right circular tubular configuration, and may enclose the support330and the guide beam332when the manipulator302is assembled. The shaft portion348may enclose the support330when the manipulator302is assembled. The bores352of the support330may align with a corresponding pair of bores354in the handpiece portion350. A pin (not shown) may secure the support330to the frame346in each of the bores352and354. In the exemplary embodiment shown, the shaft portion348may form the exterior surface of the shaft304.

In one embodiment, the handpiece portion350of the frame346includes opposing flanges356a,356bdefining a channel358. The handpiece portion350may therefore have a U-shape cross-sectional configuration and is enclosed in the housing halves310a,310b. Each of the flanges356a,356bincludes one or more slots that guide a portion of the clamping mechanism320, described below. In the exemplary embodiment shown, each flange356a,356bincludes a slot360a,360b, respectively. As shown, each of the slots360a,360bis elongated in a direction generally parallel with the longitudinal axis of the frame346. In addition, each flange356a,356bmay include a pair of through bores370a,370band372a,372b. As shown inFIG. 16, the bores370a,370band372a,372bare spaced apart with the corresponding slot360a,360bin between the pairs of bores370a,372aand370b,372b.

With reference toFIGS. 16, 17, and 18, during an operation, the surgeon may engage the clamping mechanism320, which withdraws the flexible member46from the end effector40. As is described above, withdrawing or pulling the flexible member46from the end effector40draws the anvil42toward the cartridge44and tensions the flexible member46when the anvil42and the cartridge44meet resistance to movement. By applying a force to the flexible member46, the anvil42and the cartridge44may be moved toward one another (as is indicated by arrow52inFIG. 15) and may also apply a clamping force to tissue situated between the anvil42and the cartridge44.

To that end, and with reference toFIG. 16-19, the clamping mechanism320includes a lever380pivotally coupled between housing halves310a,310band movable between a disengage position (FIGS. 17 and 18) in which the anvil42is spaced apart from the cartridge44and an engaged position (FIG. 19) in which the anvil42is moved toward the cartridge44and may clamp the tissue situated between the anvil42and the cartridge44. The lever380may be pivotally coupled within the handpiece306via a hub382, which is rotatable about a fastener384. A torque arm386extends outwardly from the hub382and is rotatable in the same direction as the lever380. For example, as is shown inFIGS. 17 and 18, the lever380is rotatable in the counterclockwise direction (as is indicated by arrow388), and the torque arm386also rotates in the counterclockwise direction. A tab390extends from the hub382and cooperates with the stapling mechanism322and/or the cutting mechanism324, described below. A locking arm398also extends from the hub382and is described in conjunction with the locking mechanism326below.

With reference toFIGS. 17 and 18, the torque arm386is pivotably coupled to a push bar392by pin394at one end thereof. The push bar392is coupled to a clamping rod396at the other end thereof. As shown, the clamping rod396is oriented generally perpendicularly to the longitudinal axis of the shaft304and is slidably engaged with each of the slots360aand360bof the frame346. Additional rods400and402having a similar orientation as the clamping rod396and are positioned in the through bores370a,370band372a,372b. As is shown best inFIG. 18, the flexible member46alternately weaves partway around each of the rod400, the clamping rod396, and the rod402. With this configuration, the clamping rod396interacts with the flexible member46when the surgeon squeezes the lever380.

In that regard, as the surgeon squeezes the lever380, it rotates counterclockwise toward the main body306, the torque arm386rotates counterclockwise forcing the push bar392generally in the direction of the end effector40as is indicated by arrow406. In turn, the clamping rod396is pushed longitudinally along the slot360a,360bwhich carries the flexible member46in the same direction. Because each of the rods400and402are stationary and the flexible member46is woven around the rods400,402in the opposing direction as compared to the clamping rod396, the path length of the flexible member46through the rods396,400, and402is increased as the clamping rod396moves toward the end effector40. That is, squeezing the lever380increases the path length of the flexible member46in the manipulator302. This increase in the path length of the flexible member46withdrawals the flexible member46from the end effector40and so retracts the anvil42toward the cartridge44.

InFIG. 19, the clamping mechanism320is fully engaged where the lever380is proximate the main body306. When the lever380is fully depressed, the rod396may be pushed to the other end of the slots360aand360b. In other words, prior to engaging the clamping mechanism320, the clamping rod396may be positioned at the end of the slots360aand360bfurthest from the end effector40, and, following engagement of the clamping mechanism320, the clamping rod396may be positioned at the end of the slots360aand360bclosest the end effector40. The length of the slots360a,360band the stroke of the torque arm386may determine how much of the flexible member46is withdrawn from the end effector40. It will be appreciated that the anvil42and the cartridge44may sufficiently compress the stomach10before the clamping rod396reaches the furthest extent of the slots360aand360b. That is, less than full depression of the lever380may achieve clamping of the stomach10.

Once the surgeon engages the clamping mechanism320, the surgeon may then engage each of the stapling mechanism322and the cutting mechanism324. With reference toFIGS. 18 and 19, the stapling mechanism322may include a stapling lever410, which is operably coupled to a stapling hub412. The hub412is pivotably coupled between the housing halves310a,310bvia the fastener384. The hub412may be adjacent the hub382on the fastener384. The stapling lever410has a U-shaped cross section and so surrounds the clamping lever380when the stapling lever410is fully depressed. The U-shaped cross-section of the stapling lever410includes a stop surface414, which is configured to engage the tab390on the hub382. In this regard, squeezing the lever380rotates the tab390into contact with the stop surface414. As a consequence, squeezing the clamping lever380may also slightly engage the stapling mechanism322and/or the cutting mechanism324as is generally shown by comparison ofFIGS. 18 and 19.

With reference toFIGS. 17-19, one or more engagement elements416may project from the hub412to frictionally engage a chain418consisting of a plurality of links420coupled at joints422. Each of the links420may be between a minimum length and a maximum length sufficient to allow the chain418to bend around the hub412in contact with the elements416while being capable of being forcibly pushed by the engagement elements416toward the end effector40without kinking, the reason for which is described below. By way of example and not limitation, each link420may be from about 20 mm to about 40 mm long.

As shown, one portion of the chain418may be loose or freely hanging within a portion of the housing halves310a,310b. Another portion of the chain418may be coupled to an actuator plate424proximate the shaft portion348of the frame346. The actuator plate424may be similar to the actuator plate214described with reference toFIGS. 8 and 9, above. In that regard, the actuator plate424may include slots426aand426b(shown best inFIG. 16A). Each slot426a,426bcooperates with the corresponding wedge push bar226a,226b. The actuator plate424also includes an elongated slot428which slidably receives the knife push bar250. Each of the push bars226a,226band250are described above with reference to the embodiment shown inFIGS. 3-14.

With reference toFIGS. 19 and 20, once the clamping mechanism320is engaged, the surgeon may engage the stapling mechanism322by squeezing the lever410. Rotating the lever410in the counterclockwise direction according to arrow430also rotates the engagement elements416counterclockwise. The engagement elements416therefore forcibly push the chain418and consequently the actuator plate424toward the end effector40, as is indicated by the arrow432. In this manner, the wedge push bars226a,226bare extended into the end effector40with the wedges230a,230bforcing staples through the stomach10as is described above with reference toFIGS. 10-12.

With reference toFIG. 20, the stapling lever410may then be cycled in a clockwise direction as is indicated by arrow440while the clamping lever380remains compressed. Cycling the lever410may be required to further push the chain418toward the end effector40to drive the wedges230a,230bacross the full length of the stomach. This may require a ratcheting type motion in which the surgeon repeatedly cycles the lever410to gradually push the chain418toward the end effector40. In this regard, it will be appreciated that the length of the chain418may be about equal to the length of the end effector40so that cycling the lever410continuously drives the wedges230a,230band the cutting edge252the length of the end effector40.

In one embodiment, once the surgeon engages the stapling mechanism322, the surgeon may then engage the cutting mechanism324. In the exemplary embodiment shown, the cutting mechanism324shares the same structure as the stapling mechanism322. In particular, with reference toFIGS. 18-20, the cutting mechanism324may include the lever410that drives the engagement elements416, and thus the chain418, toward the end effector40. The chain418drives the actuator plate424, which may also drive the knife push bar250. Thus, squeezing the lever410drives the cutting edge252across the length of the cartridge44, as is described above in conjunction withFIGS. 8 and 9. Similar to the stapling mechanism322, the surgeon may repeatedly cycle the lever410in a clockwise and counterclockwise manner to drive the cutting edge252across the length of the cartridge44. In the embodiment shown, cycling the lever410engages both the stapling mechanism322and the cutting mechanism324.

In one embodiment, even though the actuator plate424is operably coupled to each of the wedge push bars226a,226band the knife push bar250, engagement of the stapling mechanism322occurs prior to actuation of the cutting mechanism324. In other words, the stapling mechanism322engages prior to engagement of the cutting mechanism324. The elongated slot428in the actuator plate424is oversized relative to the portion of the knife push bar250that is engaged with it. These configuration results in sliding space between the slot428and the knife push bar250. The knife push bar250therefore slides relative to the actuator plate424during initial movement of the plate424. The length of the movement of the actuator plate424without movement of the knife push bar250is predetermined.

The elongated slot428is also longer than each of the slots426a,426b. Because the knife push bar250is slidably received in the elongated slot428, the initial movement of the actuator plate424in the direction of arrow432inFIG. 19causes each of the wedge push bars226a,226bto move in direct relation to the movement of the actuator plate424. The movement of the knife push bar250is however delayed relative to the movement of the wedge push bars226a,226b. This means that there is a delay between activation of the stapling mechanism322and the cutting mechanism324. This delay is proportional to the free sliding space between the elongated slot428and the knife push bar250. When the surgeon cycles the lever410, the actuator plate424moves in the same direction and carries the wedge push bars226aand226bwith it. The knife push bar250does not initially move. Instead, the actuator plate424must move a predetermined distance corresponding to the free sliding space in the direction of the end effector40before the actuator plate424engages the knife push bar250. This delay in movement between the wedge push bars226a,226band the knife push bar250results in a difference in activation time between the stapling mechanism322and the cutting mechanism324. In this manner, in one embodiment, activation of the stapling mechanism322precedes activation of the cutting mechanism324.

Once the surgeon activates each of the stapling mechanism322and the cutting mechanism324by squeezing the lever410, stapling and cutting may occur substantially simultaneously. By way of example only, the stapling of the stomach10may precede the cutting of the stomach10. That is, after an initial delay between stapling and cutting, during which the stapling mechanism322is activated, both of the stapling mechanism322and the cutting mechanism324are active. The surgeon may continue stapling and cutting the stomach10by cycling the lever410until there are no more links420in the chain18available or until the wedges230a,230breaches the end of the cartridge44. It will be appreciated that the stroke of the stapling mechanism322and the cutting mechanism324may be greater than the overall length of the stomach10or may be approximately equal to the length of the end effector40. At this point, the wedge tips230a,230bmay be proximate the distal end42a,44aof the end effector40. The end effector40and the shaft304may then be removed from the abdominal cavity with the stomach10having the configuration shown in, for example,FIG. 2E.

With reference toFIGS. 16-19, in which like reference numerals refer to like features throughout the figures, in one embodiment, the locking mechanism326locks the clamping mechanism320in the engaged position. That is, when the surgeon engages the clamping mechanism320to a predetermined clamping force, the locking mechanism326engages. The surgeon may therefore then release the lever380and the clamping force produced by the clamping mechanism320is at least partially maintained. For example, the locking mechanism326may maintain a pressure equivalent to the second stage clamping pressure described above from about 4 g/mm2to about 70 g/mm2. At these pressures, the clamping mechanism320squeezes tissue fluid out of the stomach and thereby approves staple line integrity.

To that end, in one embodiment, the housing halves310a,310benclose a portion of the locking mechanism326. The locking mechanism326includes a release lever442(shown in the form of a button) that projects from the housing halves310a,310b, for example, from a backside of the pistol-grip device306. The surgeon may therefore operate the lever442with a thumb or a forefinger. The release lever442may be pivotally mounted within the housing halves310a,310babout a fastener452and operably coupled to a spring (not shown) mounted on a support446which may bias the lever442in an outwardly direction from the pistol-grip device306. The lever442may include a locking finger448that is positioned proximate the locking arm398. The locking finger448may be biased into engagement with the locking arm398during manipulation of the clamping lever380and so automatically engage after a predetermined rotation of the lever380.

With reference toFIGS. 19 and 20, during use of the endocutter stapling device300, the surgeon may compress the clamping lever380, as described above. At a predetermined amount of rotation of the hub382, the locking arm398slidably contacts the locking finger448. The locking mechanism326may include structural features that permit only one-way rotational movement of the lever380. By way of example only, the locking arm398may include a notch450that slidably receives the locking finger448. The notch450is configured to receive the locking finger448when the locking arm398rotates in the counterclockwise direction but inhibits relative movement between the locking finger448and the locking arm398in the clockwise direction. Once the surgeon releases the clamping lever380with the locking finger448engaged in the notch450, the clamping lever380is not free to rotate in the clockwise direction. That is, the locking mechanism326prevents release of the clamping mechanism320.

When the surgeon lets go of the clamping lever380, the locking mechanism326maintains the clamping mechanism320at a predetermined engagement level. It will be appreciated that while the locking mechanism326is shown to engage the clamping mechanism320when the lever380is fully compressed, embodiments of the present invention are not limited to full compression of the clamping lever380for engagement of the locking mechanism326. Rather, the position of the locking arm398and the notch450relative to the locking finger448may be adjusted to a location at which the clamping lever380is only partially depressed before the locking finger448engages the notch450. In this regard, the surgeon may continue to compress the lever380such that the notch450rotates past the locking finger448. The surgeon may then release the clamping lever380such that the locking arm398rotates clockwise for a predetermined distance before the locking finger448engages the notch450.

Once the locking mechanism326is engaged by rotating the locking arm398to a position at which the notch450engages or rotates past the locking finger448, the surgeon may release the locking mechanism326by pressing the lever442. When the lever442is pressed, the locking finger448rotates out of interference with the notch450and the locking arm398is free to rotate clockwise to a disengaged position.

With reference now toFIGS. 21-68, in addition to the end effector40described above, there may be several alternative arrangements of the flexible member46relative to the anvil42and the cartridge44in the exemplary endocutter stapling devices100,300. In this regard,FIGS. 21-23are schematic illustrations of exemplary end effectors that may be alternatives to the end effector40described above. In the exemplary alternative configurations, the pathway of the flexible member differs from the end effector40described above. However, in each embodiment, the flexible member(s) movably couple the anvil and the cartridge and is configured to be tensioned to provide a clamping force and that clamping force is distributed between the anvil and cartridge by two points of connection at each end of the end effector. Each anvil may be separable from each cartridge so that they may be individually inserted through a trocar and then movably coupled together. Further, while a specific arrangement of anvil and cartridge may be inferred from any single one of the figures, it is contemplated that the arrangement may be reversed. Thus, embodiments of the invention are not limited to the arrangement inferred from the figures unless otherwise stated. It will be appreciated that each of the end effectors described herein may be operably coupled to a manipulator, such as, the manipulator102or302described above with reference toFIGS. 3 and 15, or another manipulator unless stated otherwise. The surgeon may therefore tension the flexible member via a manipulator.

InFIG. 21-23, an end effector500includes an anvil502and a cartridge504. The flexible member46has a first end506that is fixed to the cartridge504at one location. The paths by which the flexible member46exits the end effector500differ between each of theFIGS. 21-23. A second end508of the flexible member46may be positioned outside the patient and be pulled or otherwise manipulated by the surgeon so as to increase the tension in the flexible member46, and thereby generate a clamping force between the anvil502and the cartridge504.

By way of example, inFIG. 21, the end506of the flexible member46is fixed to the cartridge504adjacent a distal end504athereof, passes into the anvil502at a distal end502a, passes along the anvil502, out of a proximal end502bthereof, and into then out of a proximal end504bof the cartridge504. The end508of the flexible member46then extends to one of the manipulators102,302and may be manipulated as described above. InFIG. 22, the end506of the flexible member46is fixed to the cartridge504near the proximal end504band passes into the anvil502near the proximal end502b, extends along the anvil502, out of the distal end502aof the anvil502, into the cartridge504near the distal end504a, along the cartridge504, and out of the cartridge504at the proximal end504b. The second end508of the flexible member46may be positioned outside the patient and be pulled or otherwise manipulated by the surgeon so as to increase the tension in the flexible member46, and thereby generate a clamping force between the anvil502and the cartridge504.

InFIG. 23, the end506of the flexible member46is fixed to the cartridge504adjacent the proximal end504bthereof and extends along the length of the cartridge504toward the distal end504a. The flexible member46passes out of the cartridge504adjacent the distal end504athereof and passes into the anvil502adjacent the distal end502athereof. The flexible member46extends along the length of the anvil502and out of the anvil502adjacent the proximal end502bthereof. The flexible member46then passes back into the cartridge504adjacent the proximal end504bthereof and out the proximal end504bof cartridge504. The second end508may be positioned outside the patient and pulled or otherwise manipulated by the surgeon to increase the tension in the flexible member46, and thereby generate a clamping force between the anvil502and the cartridge504.

In alternative embodiments, there may be more than one flexible member used to tension the anvil and cartridge to generate a clamping force on the tissue. In this regard,FIGS. 24-26are schematic illustrations of exemplary configurations of the anvil502and the cartridge504coupled together via two flexible members configured to be tensioned to provide a clamping force between the anvil502and the cartridge504. InFIG. 24, a first flexible member510has a first end510afixed to the anvil502adjacent the distal end502athereof and passes out of the anvil502adjacent the distal end502a. The first flexible member510then passes into the cartridge504adjacent a distal end504athereof and extends along the cartridge504and out of the proximal end504bof the cartridge504. The second end510bof the first flexible member510may be positioned outside the patient. The arrangement further includes a second flexible member512having a first end512afixed to the anvil502adjacent the proximal end502bthereof and passes out of the anvil502adjacent the proximal end502bthereof. The second flexible member512then passes into the cartridge504adjacent the proximal end504band passes out of the cartridge504at the proximal end504b. The second end512bof the second flexible member512may be positioned outside the patient.

With this arrangement, the second ends510b,512bmay be kept separate or joined and may be pulled or otherwise manipulated by the surgeon with a manipulator, as described herein, to increase the tension in the flexible members510,512and thereby generate a clamping force between the anvil502and the cartridge504. In one aspect, this arrangement advantageously provides for independent control of the clamping forces at the distal ends502a,504aand the proximal ends502b,504bof the end effector500. In this regard, increasing the tension in the first flexible member510will draw the distal ends502a,504aof the anvil502and the cartridge504towards each other, as shown. As the distance between the distal ends502aand504adecreases, the clamping force at the distal end of the end effector500may increase. In a similar manner, increasing the tension in the second flexible member512will draw the proximal ends502b,504bof clamp members502,504towards each other. As the distance between the proximal ends502b,504bdecreases, the clamping force at the proximal end of the end effector500may increase. The increase in tension may depend on whether the anvil502and the cartridge504encounter resistance to movement, such as when the anvil502and the cartridge504begin compressing tissue. In another aspect of the exemplary embodiment shown inFIG. 24, the independent control of the flexible members510,512allows for independent control of the gap between the anvil502and the cartridge504at the distal ends502a,504aand the proximal ends502b,504bof the end effector500.

FIG. 25illustrates the end effector500according to the embodiment inFIG. 24where the distance between the distal end502aof the anvil502and the distal end504aof the cartridge504is less than the distance between the proximal ends502b,504bcreating an overall shape of the end effector500that is generally trapezoidal. In other words, the anvil502and the cartridge504may be in non-parallel relation, as was described above. The gap between the anvil502and the cartridge504varies from one end to the other. This non-fixed, or adjustable, gap configuration permits adjustment of the distance between the anvil502and the cartridge504to accommodate variations in thickness of the anatomical structure, such as the stomach, as it is compressed. This feature may be beneficial because it allows for different tissue thicknesses to be clamped at nearly the same clamping force both proximally and distally and may prevent overcompression of the tissue and, as a consequence, may prevent tissue damage. By way of example, and with reference toFIG. 1, the proximal end14of the stomach10generally has a thickness less than that of the distal end16of the stomach10. Accordingly, the ranges of clamping force used in the two-stage clamping process, as described above, may vary at the distal and proximal ends14,16of the stomach10. The end effector according to embodiments of the invention may permit the surgeon to vary the clamping force along the length of the stomach10and may aid in creating an improved resection line. Further, the end effector according to embodiments of the invention may permit the surgeon to vary the gap between the anvil and the cartridge along the length of the stomach10from parallel-gap configurations to non-parallel gap configurations.

With reference toFIG. 26, the end effector500includes two flexible members in a side-by-side U-shaped arrangement. A first flexible member510passes through each of the anvil502and the cartridge504, and a second flexible member512passes through each of the anvil502and the cartridge504. Notably, the first flexible member510extends along each of the anvil502and the cartridge504adjacent a first edge520of the anvil502and the second flexible member512extends through each of the anvil502and the cartridge504adjacent a second edge522of the anvil502. This arrangement advantageously provides for independent control of the opposing sides, as well as the ends, of the end effector500. In this regard, increasing the tension in the first flexible member510will increase the clamping force between the edges520. In a similar manner, increasing the tension in the second flexible member512will increase the clamping force between the edges522. This ability to control the clamping force along the opposing edges520,522of the end effector500may be advantageous in certain applications and may additionally facilitate axial alignment between the anvil502and the cartridge504.

With reference toFIG. 27, the end effector500includes two flexible members in a double loop configuration. A proximal loop526is formed with the first flexible member510, which passes into the proximal end504bof the cartridge504at two spaced apart locations, out of the cartridge504adjacent the proximal end504bat two spaced apart locations, and into the anvil502at the proximal end502bat two spaced apart locations to complete the loop526. A distal loop528is formed with the second flexible member512, which passes into the proximal end504bof the cartridge504at two spaced apart locations, along the cartridge504at spaced apart travel paths, out of the cartridge504at two spaced apart locations adjacent the distal end504a, and into the anvil502at the distal end502aat two spaced apart locations to complete the loop528. This configuration may provide increased clamping force, improve alignment, and improved stability between the anvil502and the cartridge504. In addition, the surgeon may selectively control one of the proximal loop526and/or the distal loop528.

With reference toFIG. 28, the end effector500includes a single flexible member that is double looped. The end506of the flexible member46is anchored to the cartridge504and forms a loop530through the anvil502, passes through the cartridge504, forms a second loop532through the anvil502, and passes out of the proximal end504bof the cartridge504.

InFIG. 29, the flexible members510,512has an arrangement similar to the end effector500shown inFIG. 24with the addition of structural features that facilitate alignment of the anvil502with the cartridge504. In that regard, the anvil502includes an alignment pin534adjacent the distal end502aand an alignment pin536adjacent the proximal end502b. The cartridge504includes a mating recess538and540for each of the pins534and536at each end504aand504bof the cartridge504. The flexible member510may pass through the alignment pin534and the recess538and is anchored to the anvil502. The flexible member512passes through the alignment pin536and the recess540and is also anchored to the anvil502. During use, the recesses538and540receive alignment pins534,536and facilitate alignment between the anvil502and the cartridge504.

In the embodiment shown inFIGS. 30A and 30B, the flexible members510,512have a similar arrangement as the flexible members510,512shown inFIG. 24. In addition, the anvil502includes a recess542adjacent the distal end502a. The recess542receives a hood544that covers a knife edge546. The hood544may align with the recess542during use of the end effector500when the anvil502is retracted toward the cartridge504(shown inFIG. 30B). The end effector500also includes a wedge sled548, which is pulled according to arrow550from the distal end toward the proximal end of the end effector500to staple and cut tissue.

While the flexible members are shown to follow straight paths through the anvil502and the cartridge504, such as through a straight hollow passage, embodiments of the present invention are not limited to straight paths. For example, in the embodiment shown inFIG. 31, the flexible member46follows a non-linear path552through the anvil502. In the exemplary embodiment shown, the non-linear path552may be triangular or arcuate shaped, however, other configurations are possible. This configuration may facilitate additional compression in the middle portion of the anvil502and so counteract any tendency of the anvil502to bow and bulge outwardly in the middle during compression of the tissue.

In an exemplary embodiment that counteracts bowing of the anvil and with reference toFIGS. 32A and 32B, a non-linear path552may be achieved with a strut mechanism554, which is coupled to a guide line556. It will be appreciated that the guide line556may extend outside the patient and be accessible to the surgeon. The strut mechanism554is pivotably coupled to the anvil502and is rotatable about a pivot point558. InFIG. 32B, the strut mechanism554is activated by pulling the guide line556in the direction of arrow562(inFIG. 32A). The strut mechanism554pivots into position according to arrow564inFIG. 32Aunder the tension from the guide line556. Once the strut mechanism554is active, tension on the flexible member46substantially prevents the anvil502from bowing in the central portion during compression of the stomach between the anvil502and the cartridge504.

In one embodiment and with reference toFIG. 33, a gap566between the anvil502and the cartridge504is adjustable. By way of example only, and not limitation, the gap566, or the finishing position of the anvil502when clamped, is adjustable by an adjustment mechanism570, such as, by a knob (which may be located on the manipulator102or the manipulator302). The surgeon may adjust the knob570to essentially reposition the flexible member46relative to the cartridge504and thus change the gap566. In one aspect, this arrangement advantageously provides for control of the clamping force provided by the end effector500. In this regard, as the gap566decreases, the clamping force on the anatomical structure may increase. Adjustment of the gap566may include relocation of the knob570along an axial direction572toward and away from the end effector500. This may be advantageous in that the finish position of the anvil502may determine the configuration of the staple (not shown) once deformed. It will be appreciated that as the finish position of the anvil502is moved toward the cartridge504, the final, deformed configuration of the staples may change from a less than optimal open B-shaped to a more optimal B-shape. In this way, the surgeon may correct the gap566to optimize the deformed staple configuration. In this embodiment, the gap566may remain in a parallel configuration before and after adjustment.

In one embodiment and with reference toFIG. 34, there is a similar gap adjustment device to that shown inFIG. 33and described above. In addition to the knob570for adjustment of the gap566, the manipulator102,302may include a spring574in line with a least one end of the flexible member46. WhileFIG. 34depicts the spring574joining ends of the flexible member46, it will be appreciated that the spring574may be positioned in series with one end of the flexible member46, and not be connected to each end thereof. The spring574provides a spring force to the flexible member46and thus may enable more consistent application of clamping pressure to the stomach. For example, the spring574may facilitate application of from about 8 g/mm2to about 70 g/mm2of compression on the stomach. By way of example, the spring574may have a spring force of about 44 lb. By way of further example, the spring574may have a spring force of about 385 lb. In one exemplary embodiment, shown inFIG. 35, the spring574is secured to the flexible member46in a loop configuration by a pulley576. (By comparison, the spring574inFIG. 34is in line with the flexible member46.) In particular, inFIG. 35, the spring574is secured to a threaded nut578at one end and the pulley576at the other end. The surgeon may adjust the nut578to provide the optimal gap for a target closing pressure between the anvil502and the cartridge504. The nut578may be locked in position during stapling to lock in the gap during staple formation.

In one embodiment and with reference toFIGS. 36-40B, in which like reference numerals refer to like elements inFIGS. 3-20, an end effector600has connections at the distal end and the proximal end with each being of a different type. In the exemplary embodiment shown, the end effector600has a hinge602between an anvil604and a cartridge606at a distal end600aof the end effector600. The flexible member46connects the anvil604and the cartridge606at the proximal end600bof the end effector600, similar to embodiments disclose above. With the hinge602, the anvil604rotates substantially in a plane between a disengaged position (shown inFIGS. 36 and 37) prior to and following the procedure and an engaged position when the anvil604is positioned to compress the stomach against the cartridge606(shown inFIGS. 38 and 39). To rotate the anvil604from the disengaged position to the engaged position, the surgeon pulls the flexible member46(according to arrow608) from the end effector600. Pulling the flexible member46rotates the anvil604(according to arrow610) toward the engaged, closed position shown inFIG. 38. Tension on the flexible member46clamps tissue between the anvil604and the cartridge606and may be responsible for the clamping force.

In one embodiment, and with reference toFIGS. 37 and 38, the end effector600includes an alignment mechanism612to more accurately align the anvil604with the cartridge606in the closed position. To that end, a pin614guides the flexible member46as the surgeon pulls it from the end effector600. As the anvil604approaches the engaged, closed position, the alignment mechanism612ensures that the anvil604is accurately positioned relative to the cartridge606. By way of example, and not limitation, alignment between the anvils and cartridges, as described herein, may mean an accuracy of plus or minus 0.002 inches. Alignment between the two improves the quality of the staple placement and deformation. The alignment mechanism612is positioned at at least the proximal end600bof the end effector600and may guide the anvil604into the closed position. To do so, the alignment mechanism612may engage the anvil604just prior to the anvil604reaching the closed position. The last portion of the movement of the anvil604toward the cartridge606may be guided by the alignment mechanism612.

To that end, in the exemplary embodiment shown inFIGS. 36, 37, and 38, the cartridge606includes a frame640at least partially enclosing a cartridge body638defining a face618. The cartridge body638houses the staples198and staple drivers200. A slot636opens to the face618and extends through the cartridge body638and the frame640to open to an outer surface of the cartridge frame640(shown best inFIG. 38). The anvil604includes a tubular body642having an anvil plate644that defines an anvil face632and an interior surface646. A slot634opens to each of the face632and the interior surface646.

The alignment mechanism612includes a housing616that extends outwardly beyond the face618of the cartridge606(shown best inFIG. 36). The housing616may support a knife620, described below, having a cutting edge (not shown), which performs substantially the same function as the cutting edge252described above and shown, for example, inFIG. 6. The alignment mechanism612may also include a recess624in the plate644of the anvil604. The recess624is connected to the slot634and is sized to receive the housing616and/or the knife620. With reference toFIG. 39, the knife620has an I-shaped configuration, much like an I-beam, and has a top flange626, a bottom flange628, and a web630connecting the top flange626to the bottom flange628. A portion of the web630that faces the distal end600aof the end effector600includes the cutting edge. As shown inFIG. 38, the top flange626may have a slightly rounded configuration. When the knife620resides in the housing616, they collectively form a protrusion.

With reference toFIGS. 37 and 38, during the closing motion of the anvil604, as the anvil604approaches the cartridge606, the housing616and the flange626are received in the recess624. Thus, if the anvil604is not aligned with the cartridge606as it approaches the engaged position, the housing616and the top flange626may contact the face632of the anvil604, the rounded surface of the top flange626may urge realignment of the anvil604with the cartridge606so that the recess624may be brought into full engagement with the top flange626in the housing616. In this manner, the alignment mechanism612facilitates alignment between the anvil604and the cartridge606.

Once the anvil604is aligned with the cartridge606, the surgeon may engage a stapling mechanism and a cutting mechanism, each similar to the stapling mechanism124,322and the cutting mechanism126,324described above with reference toFIGS. 3-20. In that regard and with reference toFIGS. 38 and 39, the slot634slidably receives the web630of the knife620. Similarly, the slot636also slidably receives the web630of the knife620as the knife620is forced toward the distal end600aof the end effector600according to arrow648. The flanges626and628also engage the anvil604and the cartridge606, respectively. Specifically, the flange626engages the interior surface646of the face plate644and the flange628engages the exterior surface of the frame640. This configuration improves the rigidity of the end effector600during cutting/stapling by capturing each component and preventing separation of the anvil604from the cartridge606in multiple directions. The I-beam configuration may substantially prevent any torque produced by the stapling/cutting action from twisting the anvil604relative to the cartridge606as can be appreciated by the cross-section shown inFIG. 39in which the knife620is shown to positively lock the anvil604relative to the cartridge606and thereby prevent their separation as well as prevent any significant relative side-to-side motion during cutting/stapling.

With reference toFIGS. 40A and 40B, in one embodiment, the face plate644includes a distal recess652and a distal housing654extends from the cartridge body638. As the knife620is forced along the slots634,636, it enters the housing654(shown inFIG. 40B) to complete stapling and/or cutting. The anvil604may then be rotated about the hinge602to a disengaged position. The recess652allows the knife620and housing654to pass through the plate644as the anvil604is pivoted about the hinge602.

Embodiments of the present invention are not limited to a distal hinge, as other structures may be utilized to secure and align the proximal and distal ends of the anvil relative to the cartridge. With reference toFIGS. 41-63, in which like reference numerals refer to like features through the figures, in one embodiment of the invention, an end effector700includes an anvil702and a cartridge704, for performing for compressing, stapling, and/or cutting a stomach. As with the end effectors described above, the end effector700may be coupled to a manipulator, such as, the manipulator102and302(shown inFIGS. 3-20and described above), or another manipulator, by which the surgeon may remotely operate the end effector700. The anvil702has a face706and the cartridge704has a face708. During use of the end effector700, and as is schematically shown inFIG. 42, the face706of the anvil702is pulled into a position opposite the face708of the cartridge704. Instead of a hinge, the cartridge704includes a cam tube710that slidably receives the anvil702during a surgical procedure. The cam tube710may be a hollowed out area within the cartridge704that projects above the face708of the cartridge704. As shown, the cam tube710includes a curved or arcuate surface712. The anvil702includes an arcuate surface714that is configured to cooperate with the arcuate surface712of the cam tube710, as is shown inFIG. 42.

Similar to the configuration shown inFIG. 24, described above, the surgeon may manipulate two flexible members510,512that are connected to the anvil702to compress a stomach or other tissue between the anvil702and the cartridge704. In particular, and by way of example only, the flexible member510is anchored to a distal end702aof the anvil702, passes into a distal end704aof the cartridge704through the cam tube710. From the distal end704aof the cartridge704, the flexible member510passes along the length of the cartridge704and out of a proximal end704bof the cartridge704for manipulation by the surgeon. The flexible member512is anchored to a proximal end702bof the anvil702, passes into the cartridge704adjacent the proximal end704bof the cartridge704, and passes out of the proximal end704bfor manipulation by the surgeon.

As the surgeon tensions the flexible member510, the anvil702is pulled into the cam tube710(shown inFIG. 42). It will be appreciated that the surfaces712,714may cooperate to provide a compressive force generally toward the face708of the cartridge704when the surgeon tensions the flexible member510to pull the distal end702aof the anvil702into the cam tube710. Tensioning the flexible member512pulls the proximal end702bof the anvil702toward the cartridge704to compress tissue situated between the face706and the face708. Once the anvil702is in position relative to the cartridge704or a target compression of the tissue is achieved as determined by the tension on one or both of the flexible members510,512, the surgeon may staple and cut the compressed tissue, as described above with reference toFIGS. 3-20. It will be appreciated that the configuration of the cartridge704shown inFIG. 41may require the surgeon to tension the flexible member510first to guide the distal end702ainto the cam tube710. The surgeon may then tension the flexible member512to bring the anvil702into the position shown inFIG. 42.

With continued reference toFIGS. 41 and 42, in one embodiment, the anvil702includes anvil pins718, and the cartridge704includes channels720that are configured to receive the anvil pins718. As shown, the anvil pin718is disposed proximate the distal end702aof the anvil702and projects outwardly from the outer surface of the anvil702. The channels720are disposed proximate the distal end704aof the cartridge704within the cam tube710. As shown, the channel720is open toward the proximal end704bof the cartridge704and is angled in a direction toward the face708of the cartridge704. The channel720terminates proximate the distal end704aof the cartridge704nearer to the face708than the opening of the channel720. While not shown inFIGS. 41 and 42, it will be appreciated that an anvil pin may be disposed on each of the right and left sides of the anvil702. Similarly, the cartridge704may include channels disposed inside the cam tube710on either side to receive the anvil pins.

During use of the end effector700shown inFIGS. 41 and 42, tensioning the flexible member510pulls the anvil702within the cartridge704to engage the surfaces712,714. This motion is also engages the anvil pin718within the channel720. Further tensioning the flexible member510produces a compressive force generally in the direction of the face708of the cartridge704due to the engagement between one or both of the surfaces712,714and the anvil pin718with the channel720. Advantageously, in addition to the above, the anvil pin718and channel720facilitates alignment between the anvil702and the cartridge704.

With reference now toFIGS. 43 and 44, in which like reference numerals refer to like features ofFIGS. 41 and 42, in one embodiment of the invention, the anvil702includes an anvil lever724positioned on the surface714proximate the distal end702a. The cartridge704includes a slot726configured to receive the anvil lever724as the cartridge704is drawn into the cam tube710. Advantageously, the combination of the anvil lever724and the slot726aligns the anvil702with the cartridge704. This alignment ensures that the staple channels (described above) are adjacent to the corresponding staple pockets (described above) on the anvil702. In addition, as is shown inFIGS. 43 and 44, a single flexible member46may be anchored to the cartridge704proximate the proximal end704bsimilar to the configuration shown inFIG. 22and described above.

In one embodiment of the invention and with reference toFIGS. 45A and 45B, in which like reference numerals refer to like features ofFIGS. 21-42, the end effector700includes a distal hinge730coupling the distal end702aof the anvil702with the distal end704aof the cartridge704. The hinge730may provide alignment between the anvil702and the cartridge704in at least two directions with respect to the face708of the cartridge704. The anvil702may further include a latch732projecting from the face706proximate the proximal end702bof the anvil702. The cartridge704may include a recess734and is configured to receive the latch732when the anvil702is brought to be engaged position. As shown, the latch732may include a notch736. The cartridge704may house a pin738that projects into the recess734and that may be biased in one direction by a spring740.

The anvil702may be rotated about the hinge730to an engaged position with tissue situated between the face706of the anvil702and the face708of the cartridge704. Guided by the hinge730the surgeon may rotate the anvil702by pulling on the flexible member46through the cartridge704. In the exemplary embodiment, the flexible member46is anchored to the latch732and passes through the recess734. With reference toFIG. 45B, the latch732may enter the recess734to engage the pin738, which enters the notch736under the bias of the spring740. Thus, in this embodiment, each of the proximal end and the distal end of the end effector700is positively locked with respect to at least outward movement of the anvil702relative to the cartridge704. In view of the above, the latch732may align the anvil702with the cartridge704and maintain that alignment against forces that tend to push the anvil702an outward direction relative to the face708.

Following stapling and/or cutting, the surgeon may withdraw the pin738from the notch736by pulling a release cable742. The anvil702may then be rotated to an opened or disengaged position. In one embodiment, the end effector700further includes a release spring744(shown inFIG. 45B) that is coupled to each of the anvil702and the cartridge704. In the exemplary embodiment shown, the cartridge704houses the release spring744. When the anvil702is in the engaged position with the latch732and the recess734, the release spring744is biased in a direction to push the anvil702away from the cartridge704. That is, the release spring744is biased to disengage the anvil702from the cartridge704when the anvil702is in the engaged position. Thus, in this embodiment, when the surgeon pulls on the release cable742, the release spring744acts to push apart or separate the anvil702from the cartridge704. In this way, the release spring744assists the surgeon in opening the end effector700.

In one embodiment, and with reference toFIGS. 46-48, in which like reference numerals refer to like features ofFIGS. 21-45B, the anvil702is coupled to the cartridge704by the distal hinge730. The flexible member46passes through the cartridge704at the proximal end704band is anchored to the anvil702at the proximal end702b. As with the embodiment shown inFIGS. 45A-45B, the surgeon may rotate the anvil702to the engaged position by tensioning the flexible member46. In this way, the anvil702rotates about the hinge730toward the cartridge704as is indicated by arrow748inFIG. 46. With reference toFIG. 46, the anvil702includes a tapered surface750at the proximal end702bthat forms a wedge-like configuration at the proximal end702bof the anvil702.

The end effector700further includes a proximal cam tube752that is movable relative to the cartridge704according to the arrow754inFIG. 47. The cam tube752includes a cavity756that faces the proximal end702bof the anvil702when the anvil702is in an engaged position. The cavity756includes a wedge surface760that is positioned to engage the tapered surface750of the anvil702. After the surgeon pulls the flexible member46to engage the anvil702with the tissue between the anvil702and the cartridge704, the surgeon may force the cam tube752toward the proximal end702bas is indicated by arrow754. As the surgeon does so, the wedge surface760engages the tapered surface750. The forcible contact between the two surfaces750and760forces the anvil702toward the cartridge704. Thus, in this embodiment, each end702a,702bof the anvil702is captured to substantially prevent separation of the anvil702from the tissue. Pressure on the tissue may be increased by the forced engagement of the tapered surface750and the wedge surface760.

In one embodiment, and with reference toFIGS. 49 and 50, in which like reference numerals refer to like features ofFIGS. 41-48, the end effector700combines various features of end effectors shown and described above. In that regard, the end effector700combines the distal cam tube710and the proximal latch732. The surgeon may therefore withdraw the flexible member510to pull the anvil702into the distal cam tube710as is indicated by the arrow762. Once inserted therein, the surgeon may withdraw the flexible member512to pull the latch732into the recess734with the pin738engaging the notch736, as is shown inFIG. 50.

In one embodiment, and with reference toFIG. 51, in which like numerals refer to like features inFIGS. 41-50, the end effector700includes a distal latch764similar to the proximal latch732described above. The distal latch764on the anvil702fits within a recess766on the cartridge704. While the latch764is shown to be part of the anvil702, it will be appreciated that the latch764may be a part of the cartridge704. That is, the orientation may be reversed from that shown inFIG. 51or in any of the figures described above. As shown, the flexible member46passes through the cartridge704, out of the distal end704a, into the distal end702aof the anvil702, out of the proximal end702bof the anvil702, and into the proximal end704bof the cartridge704where it is anchored to the cartridge704. The surgeon may withdrawal the flexible member46to move the anvil702toward the cartridge704. Withdrawing the flexible member46pulls the distal latch764into the recess766. Each of the distal end702aand the proximal end702bof the anvil702is secured to the cartridge704. The latch764may be released by pulling the release cable742.

In one embodiment and with reference toFIG. 52, in which like reference numerals refer to like features inFIGS. 41-51, the end effector700includes latches at each of the ends702a,702bof the anvil702. In that regard, the end effector700includes the proximal latch732and the distal latch767. The surgeon may withdrawal the flexible member46to pull the anvil702toward the cartridge704. Pulling the flexible member46pulls each of the latches732,767into the corresponding recess734,766to secure each of the ends702a,702bof the anvil702to the cartridge704. The surgeon may pull the release cables742to release the anvil702from the cartridge704. The release cables742may be separate or may be linked within the end effector700or another portion of the device.

In one embodiment and with reference toFIG. 53, in which like reference numerals refer to like features inFIGS. 51-52, the end effector700includes a distal latch764and a proximal cam tube752. When the surgeon pulls the flexible member46, the distal latch764enters the recess766and the pin738engages the notch736to secure the distal end702aof the anvil702to the cartridge704. Once the anvil702is proximate the cartridge704, the surgeon may push the proximal cam tube752into engagement with the proximal end702bof the anvil702. The wedge surface760may engage a corresponding tapered surface750on the anvil702. As described above, forcing the wedge surface760into contact with the anvil702produces a force in the direction of the cartridge704and secures the proximal end702bto the anvil702to the cartridge704. The surgeon may release the anvil702by pulling the release cable742to disengage the latch764at the distal end702aof the anvil702and pulling the proximal cam tube752to disengage the proximal end702bof the anvil702.

In one embodiment and with reference toFIGS. 54-56, in which like reference numerals refer to like features throughoutFIGS. 41-53, the end effector700may include a knife770having a cutting edge772and a wedge sled774. The knife770may have an I-beam cross-sectional configuration similar to that shown inFIG. 39and described above. The knife770is received in a channel776in the cartridge704and in a channel778in the anvil702when the anvil702compresses tissue between the anvil702and the cartridge704. The flexible member46may pass through the cartridge704in the channel776, through the knife770in the channel778to the proximal end702bof the anvil702, out of the proximal end702b, and into the proximal end704bof the cartridge704where it is anchored. The surgeon may pull on the flexible member46to draw the anvil702toward the cartridge704.

With reference toFIG. 55, doing so pulls the knife770into the channel778and aligns the anvil702with the cartridge704at the distal ends702a,704a. At the proximal ends702b,704b, the surgeon may push the proximal cam tube752into engagement with the proximal end702bof the anvil702, as is described above, to secure and align the proximal ends702b,704b. Once secured and aligned, as is shown inFIG. 56, the surgeon may continue to pull the flexible member46. Pulling the flexible member46draws the knife770along each channel776,778to staple and cut tissue which is described above with reference toFIGS. 30A and 30B.

In one embodiment and with reference toFIGS. 57 and 58, in which like reference numerals refer to like elements inFIGS. 41-56, the end effector700includes the distal cam tube710and the proximal cam tube752. Each of the anvil702and the cartridge704are separably coupled together by the cam tubes710and752. In this regard, the surgeon may move the anvil702and the cartridge704independently of each other. Once positioned proximate the other, at least one of the cam tubes710and752is movable relative to the other along a screw782operable by the surgeon, for example, with a knob784to movably couple the anvil702to the cartridge704. In the embodiment shown, the cam tube752is movable relative to cam tube710. Rotating the knob784in one direction draws the cam tube752toward the other cam tube710, and rotating the knob784in the opposite direction pushes the cam tube752away from the cam tube710. In addition to capturing and aligning the anvil702relative to the cartridge704, the surgeon may control the gap between the cam tubes710,752by rotating the knob784to predetermined positions at which the gap between the anvil702and the cartridge704is known. In this regard, the gap may be varied by the amount of engagement between one or both of the cam tubes710,752and the anvil702. By moving both cam tubes710,752, the surgeon may control the gap between the anvil702and the cartridge704in a parallel configuration. By moving one of the cam tubes710,752, the surgeon may control the gap between the anvil702and the cartridge704in a non-parallel configuration. Further, this arrangement advantageously provides for control of the clamping force provided by the end effector700. In this regard, as the gap between the anvil702and the cartridge704decreases, the clamping force on the anatomical structure may increase.

In one embodiment and with reference toFIG. 59, in which like reference numerals refer to like elements ofFIGS. 41-58, the end effector700includes the proximal latch732with two flexible members510and512. The flexible member510passes through the cartridge704, out of the distal end704a, and into the anvil702proximate the distal end702awhere it is anchored to the anvil702. The flexible member512passes through the cartridge704, out of the proximal end704bthrough the recess734, and may be anchored to the latch732. Pulling each of the flexible members510,512draws the anvil702toward the cartridge704with the latch732entering the recess734. The pin738engages the notch736under the influence of the bias produced by the spring740to align and secure the anvil702against movement away from the cartridge704. Once the surgical procedure is complete, to release the anvil702, the surgeon may pull the release cable742allowing the pin738to disengage from the latch732. Releasing each of the flexible members510,512permits the anvil702to be moved apart from the cartridge704.

In one embodiment, and with reference now toFIG. 60, in which like reference numerals refer to like features ofFIGS. 41-59, the end effector700includes a single flexible member46having a pathway similar to that shown inFIG. 51, for example. The flexible member46is anchored proximate the proximate end704bof the cartridge704. The function of the end effector700shown inFIG. 60may be somewhat like that shown inFIG. 59with movement of the anvil702being achieved by pulling the flexible member46. The anvil702may be released by pulling the release cable742.

In one embodiment, and with reference toFIG. 61, in which like reference numerals refer to like features ofFIGS. 41-60, the end effector700includes a proximal hinge790to pivotally secure the anvil702to the cartridge704. The flexible member46passes along the length of the cartridge704, exits the distal end704aof the cartridge704, and may be anchored to the distal end702aof the anvil702. The surgeon may withdraw the flexible member46from the end effector700to rotate the distal end702atoward the distal end704aof the cartridge704. The proximal hinge790ensures alignment between the anvil702and the cartridge704at the proximal ends702b,704bthereof and also secures the anvil702to the cartridge704. In one embodiment, and with reference toFIG. 62, in which like reference numerals refer to like features ofFIGS. 41-61, the end effector700is similar to the end effector700shown inFIG. 61, but with the distal latch764described above with reference toFIG. 51. In this embodiment, the surgeon may pull the flexible member46to pivot the anvil702about the hinge790. The latch764may enter the recess766with the pin738engaging the notch736to align and secure the anvil702to the cartridge704at the distal end702a,704a. The hinge790secures the anvil702to the cartridge704at the proximal end702b,704b. The surgeon may release the distal end702afrom the cartridge704by pulling on the release cable742.

In one embodiment, and with reference toFIG. 63, in which like reference numerals refer to like features ofFIGS. 41-62, the end effector700includes the proximal hinge790but is secured at the distal end702a,704aby the flexible member46. In particular, the flexible member46passes through the cartridge704and exits the distal end704aand is configured with a loop46a. The anvil702includes a stud794that projects from the distal end702a. Although not shown, the loop46amay be coupled to the stud794. The surgeon may withdraw the flexible member46from the end effector700to rotate the anvil702toward the cartridge704. The hinge790secures the anvil702to the cartridge704at the proximal end702b,704band the loop46asecures the anvil702to the cartridge704at the distal end702a,704a.

In one embodiment, and with reference toFIGS. 64 and 65, in which like reference numerals refer to like features throughout the drawings, the end effector800includes an anvil802and a cartridge804. As with the end effectors described above, the end effector800may be coupled to a manipulator, such as, the manipulator102and302(shown inFIGS. 3-20and described above), or another manipulator, by which the surgeon may remotely operate the end effector800. InFIG. 64, a distal end802aof the anvil802is shown as having a hook806. A distal end804aof the cartridge804has a lever808. As the surgeon pulls the flexible member46, the distal end802ais pulled beneath the lever808as is shownFIG. 65. In particular, the hook806engages the lever808to align and secure the anvil802to the cartridge804.

With reference toFIG. 66, in which like reference numerals refer to like features throughout the drawings, an end effector820includes a curved anvil822having a first end822aand a second end822band a curved cartridge824having a first end824aand a second end824b. The anvil822and the cartridge824are shaped to fit together with the first ends822a,824aand second ends822b,824bin alignment when the anvil822aligns with the cartridge824. The cartridge824includes a first cam tube828and a second cam tube830. A flexible member826movably couples the anvil822with the cartridge824. The surgeon withdraws the flexible member826from the end effector820. Doing so draws the anvil822and cartridge824together with the first end822aof the anvil822entering the distal cam tube828. This configuration is similar to the distal cam tube710disclosed above with reference toFIG. 41, for example. To secure the second ends822b,824b, the surgeon pushes the proximal cam tube830to engage the anvil822. Proximal cam tubes are shown in at leastFIGS. 46-48described above.

In one embodiment, and with reference toFIGS. 67-68C, in which like reference numerals refer to like features throughout the drawings, an end effector900is capable of clamping tissue. The end effector900is coupled to a shaft910, which may be any of shafts104,304, described above, or another shaft that is operatively coupled to a manipulator. The end effector900is capable of articulating relative to the shaft910in one or more directions. The end effector900includes an anvil902and a cartridge904coupled together at a distal end906thereof by a hinge908. In particular, the hinge908couples distal ends902a,904aof the anvil902and cartridge904, respectively, together. A flexible member912is operatively coupled to a proximal end902bof the anvil902and couples the proximal end902bto the cartridge904. By way of example only, and not limitation, as is shown inFIG. 68A, an anchor914secured to an end of the flexible member912resides within an undersized bore916and couples the flexible member912to the anvil902. The flexible member912passes through the shaft910and may be accessible to the surgeon. Similar to previous embodiments, the surgeon may withdraw the flexible member912from the end effector900to rotate the anvil902about the hinge908toward the cartridge904as is indicated by arrow920inFIGS. 67 and 68A.

In addition, the end effector900may further include a compression mechanism930by which additional compressive force may be applied to the tissue situated between the anvil902and the cartridge904. In the embodiment shown inFIGS. 67-68B, the compression mechanism930includes a hook member932that extends from the proximal end902bof the anvil902. The hook member932defines a slot934. As shown inFIG. 68A, the slot934opens toward the cartridge904and is angled relative to a longitudinal axis936of the anvil902. By way of example only, the slot934is angled from about 25° to less than about 90° from the longitudinal axis936.

The compression mechanism930may also include a compression housing938that extends from a proximal end904bof the cartridge904and couples the end effector900to the remainder of the medical device (not shown) via the shaft910. The compression housing938includes two spaced-apart flanges940a,940bdefining a channel942between them. As shown, the flexible member912passes through the compression housing938. In the exemplary embodiment shown, the flexible member912passes through the channel942. Each of the flanges940a,940bdefines a slot948a,948b, respectively, that generally extends parallel to the longitudinal axis of the cartridge904. A rotation flange946(FIG. 68A) defines one end of the housing938and extends generally radially outwardly relative to the spaced-apart flanges940a,940band is described below. A compression slide950is slidable relative to the compression housing938in a direction defined by the channel942. The compression slide950carries a compression pin954that is slidably received in the slots948a,948bof the compression housing938. As is shown best inFIG. 68A, a compression cable956is coupled to the compression slide950and extends through the shaft910and may be accessible to the surgeon.

During a surgical procedure, the surgeon may withdraw the flexible member912from the end effector900. Doing so rotates the anvil902toward the cartridge904and clamps tissue between the anvil902and the cartridge904. The anvil902approaches the cartridge904with the hook932entering the channel944of the compression housing938. It will be appreciated that additional tension on the flexible member912may be insufficient to further compress the tissue between the anvil902and the cartridge904. If so, the surgeon may engage the compression mechanism930to apply additional pressure to the tissue. In that regard, the surgeon may retract the compression cable956from the end effector900.

With reference toFIG. 68B, as the surgeon retracts the compression cable956, the compression slide950is forced toward the shaft910according to arrow958. Sliding movement of the compression slide950in the channel944forces the pin954into the slot934. Because the slot934is angled relative to the longitudinal axis936(FIG. 68A), forcing the compression slide950and the pin954in the direction indicated by arrow958produces a clamping force in the direction of the cartridge904. This force pulls the anvil902toward the cartridge904and so provides additional compression of the tissue.

In one embodiment, and with reference now toFIG. 68C, according to one aspect of the invention, the end effector900may be articulated relative to the shaft910. An articulation mechanism970may provide this motion (indicated by arrows964inFIG. 68C). With reference toFIGS. 67 and 68C, in one embodiment, the articulation mechanism970includes a clevis972that is secured to the end effector900at one end and the shaft910at the other end by pins974. A portion of the clevis972is coupled to the shaft910at a pair of cutouts978at one end of the shaft910. The pin974provides a pivot point about which the shaft may rotate relative to the end effector900. In addition, the clevis972is coupled to a rotation collar976by another pin974. The rotation collar976surrounds at least a portion of each of the clevis972and the rotation flange946of the compression housing938. The rotation collar976thus frictionally couples the end effector900to the clevis972and may define a longitudinal axis980about which the end effector900may be rotatable. Embodiments of the present invention may therefore be configured to rotate about an axis nearest the end effector and pivot about an axis nearest the shaft. That is, according to embodiments of the invention, there may be an ordered arrangement between the rotation and the pivoting motion, as shown. While it may be possible for the end effector900to rotate relative to the clevis972within the rotation collar976, rotation of the shaft910may also rotate the end effector900via frictional engagement between the clevis972and the rotation collar976.

During a surgical procedure, the surgeon may desire to rotate the shaft910relative to the end effector900. Relative movement between the shaft910and the compression housing938is permitted by a combination of the clevis972and the rotation collar976. The clevis972allows bending between the end effector900and the shaft910(as indicated by arrow968inFIG. 68C), and the collar976allows rotation around the longitudinal axis of the end effector900(as is indicated by arrows964inFIG. 68C) by allowing relative movement between the clevis972and the compression housing938. It will be appreciated that when the surgeon pulls the compression cable956, the compression housing938may be forced against the clevis972. This additional applied pressure may substantially prevent relative rotation between the housing938and the clevis972and so essentially locks the orientation of the end effector900relative to the shaft910.

In one embodiment, and with reference toFIGS. 69-70B, in which like reference numerals refer to like features ofFIGS. 67-68B, an end effector1000is capable of clamping tissue. The end effector1000is coupled to the shaft910by the clevis972and is capable of articulating relative to the shaft910. To those ends, the end effector1000includes an anvil1002pivotally coupled to a cartridge1004at a hinge1006at a distal end1008thereof. The flexible member912couples the anvil1002to the cartridge1004at a proximal end1010thereof and is assessable to the surgeon. As with the embodiment shown inFIGS. 67-68Band described above, the surgeon may withdraw the flexible member912from the end effector1000to clamp tissue between the anvil1002and the cartridge1004. However, the clamping pressure achievable with the flexible member912may be insufficient. To provide additional clamping, the end effector1000may include a compression mechanism1020capable of applying additional pressure to the tissue situated between the anvil1002and the cartridge1004.

In that regard, the compression mechanism1020may include a compression wedge1022extending from the proximal end1002bof the anvil1002. The compression wedge1022may have a dogleg-like configuration and so project from the proximal end1002bof the anvil1002at an angle. With reference toFIG. 70A, the compression wedge1022includes a wedge surface1024that is oriented at a transverse angle relative to a longitudinal axis1028of the anvil1002. The wedge surface1024is angled relative to the longitudinal axis1028of the anvil1002. By way of example only, the surface1024is angled from about 10° to about 60° from the longitudinal axis1028, and by way of further example, the surface1024may be angled from about 10° to about 45° or from about 20° to about 30° from the longitudinal axis1028. It will be appreciated that the steeper the angle, the shorter the clamping stroke and the higher the clamping forces that have to be supplied. The reverse may also be true. That is, the shallower the angle, the longer the clamping stroke and the lower the clamping forces that have to be supplied.

The compression mechanism1020may also include a compression housing1030extending from the proximal end1004bof the cartridge1004. As shown best inFIG. 69, the compression housing1030includes opposing flanges1032a,1032bthat define a channel1034, which is configured to receive at least a portion of the compression wedge1022as the anvil1002clamps tissue between the anvil1002and the cartridge1004. As is shown inFIGS. 69 and 70B, a routing pin1036is coupled to each of the flanges1032a,1032band spans the channel1034. The flexible member912is slidably coupled to the pin1036and so the pin1036guides the flexible member912through the channel1034and into the shaft910.

With reference toFIGS. 70A and 70B, the compression housing1030further includes a radially extending flange1040that defines the proximal end of the compression housing1030. The radially extending flange1040defines a through bore1042through which passes the flexible member912. An attachment pin1044is coupled to the flange1040and spans the through bore1042. A compression cable1048is coupled to the attachment pin1044and extends through the shaft and may be accessible by the surgeon. A rotation collar1050slidably couples the compression housing1030to the shaft910(e.g., by the clevis972). The rotation collar1050has a partially closed end1052, which provides an interference fit with the flange1040and functions as a stop to distal movement of the compression housing1030within the flange1040. The rotation collar1050may define the longitudinal axis980about which the surgeon may rotate the end effector1000.

As is shown best inFIG. 70A, the rotation collar1050is an elongated tubular body with an overall length that exceeds the corresponding length dimension of the flange1040of the compression housing1030. Accordingly, when the anvil1002is in the disengaged position, as is shown inFIG. 70A, the flange1040is positioned adjacent the partially closed end1052within the rotation collar1050. In view of the relative difference in lengths of the flange1040and the collar1050, a gap1054exists between the flange1040and the clevis972into which the flange1040may slide as the surgeon engages the compression mechanism1020as is described below.

With reference toFIGS. 70A and 70B, the surgeon may engage the compression mechanism1020by pulling on the compression cable1048. After the anvil1002is clamped onto tissue between the anvil1002and the cartridge1004, at least a portion of the compression wedge1022may reside between the flanges1032a,1032bin the channel1034. To apply additional compression to the tissue, the surgeon may pull the compression cable1048from the end effector1000. The applied force causes relative movement between the rotation collar1050and the flange1040. Specifically, pulling on the compression cable1048pulls the flange1040in the proximal direction into the gap1054. This drives the partially closed end1052of the rotation collar1050into contact with the wedge surface1024(shown inFIG. 70B). Because of the angled orientation of the wedge surface1024, the partially closed end1052of the rotation collar1050forces the anvil1002toward the cartridge1004and accordingly applies additional pressure to the tissue situated therebetween. By this motion, a gap1056may be formed between the flange1040adjacent the partially closed end1052of the flange1040when the anvil1002is in an engaged position and the compression mechanism1020is engaged. As the gap1056increases, the gap1054is reduced.

In another aspect of the exemplary embodiment shown inFIGS. 69-70B, the surgeon may articulate the end effector1000relative to the shaft910. As with the embodiment shown inFIG. 67, the shaft910may be coupled to the end effector1000by the clevis972. The rotation collar1050captures a portion of the clevis972adjacent the flange1040. The clevis972is configured to provide pivotal motion between the end effector1000and the shaft910at a pivot point defined by one of the pins974.

In addition, and with reference toFIGS. 70A and 70B, the articulation mechanism970further includes a rotation tube1058. As shown, the rotation tube1058passes through the clevis972and the shaft910and may be operable by the surgeon. The rotation tube1058defines an elongated through bore1060that extends axially through the length of the rotation tube1058. The rotation tube1058may be a hollow flexible shaft. The compression cable1048may run axially from the end effector1000through the shaft910within the through bore1060. By way of example only and not limitation, the rotation tube1058may be fabricated from a series of tightly wound wires of multiple layers with each layer being wound opposite directions from at least one adjacent layer. It will be appreciated that the rotation tube1058allows power transmission around a bend, such as, through the clevis972when it is bent. In one embodiment, the rotation tube1058is secured to the flange1040such that rotation of the rotation tube1058rotates the end effector1000about the longitudinal axis980.

With continued reference toFIGS. 70A and 70B, in one embodiment, the articulation mechanism970includes an articulation cable1062that is coupled to the clevis972. The articulation cable1062extends from the clevis972through the shaft910to a location accessible by the surgeon. The surgeon may pull the articulation cable1062to cause the end effector1000to articulate about the pin974that couples the clevis972to the shaft910. Advantageously, the surgeon may control the degree to which the shaft910is angled with respect to the end effector1000.

In one embodiment and with reference now toFIGS. 71-72B, in which like reference numerals refer to like features ofFIG. 67-70B, the end effector1100includes an anvil1102coupled to a cartridge1104by flexible members1106and1108at proximal and distal ends1110,1112of the end effector1100, respectively. As with previous embodiments, the end effector1100is configured to clamp tissue between the anvil1102and the cartridge1104and is configured to articulate relative to the shaft910. In that regard, the end effector1100includes a compression mechanism1120and an articulation mechanism1130pivotally couples the end effector1100to the shaft910.

With reference toFIG. 72A, in one embodiment, the flexible members1106and1108are anchored to the anvil1102by anchors914, described above with reference toFIG. 68A. The flexible members1106,1108pass into and through the cartridge1104at corresponding ends thereof and through the shaft910and may be accessible to the surgeon. In this regard, the surgeon may withdraw each of the flexible members1106,1108from the end effector1100to pull the anvil1102toward the cartridge1104, as is indicated by arrow1132inFIG. 72A. It will be appreciated that the surgeon may be unable to compress tissue between the anvil1102and the cartridge1104sufficiently by tensioning the flexible members1106,1108. The surgeon may then engage the compression mechanism1120to provide additional compression of the tissue.

Referring toFIG. 71, in one embodiment, the compression mechanism1120includes a distal clamping mechanism1134at the distal end1112of the end effector1100and a proximal clamping mechanism1136at the proximal end1110of the end effector1100. The compression mechanism1120differs from the compression mechanism1020in that additional compressive forces may be applied to each and of the anvil1102. The surgeon may therefore engage each of the clamping mechanisms1134,1136to further compress the tissue between the anvil1102and the cartridge1104. Advantageously, the clamping mechanisms1134,1136may provide more uniform compression at each end1110,1112of the end effector1100.

With continued reference toFIG. 71, each of the clamping mechanisms1134,1136includes a compression wedge1138,1140, similar to the compression wedge1022described above with reference toFIG. 69, and which have a dog-leg like configuration including a wedge surface1142and1144, respectively. As is shown best inFIG. 72A, each of the surfaces1142,1144is oriented at an angle relative to a longitudinal axis1148of the anvil1102. The angles may be within the same range identified above with reference toFIG. 70Aand the wedge surface1024.

The clamping mechanism1134includes a distal cam tube1150that is movable relative to the cartridge1104on a slide1152. The cam tube1150has a cavity1154that is sized to receive the compression wedge1138. The clamping mechanism1136further includes the compression housing1030(described above with respect toFIG. 69) at the proximal end1110that is configured to receive the compression wedge1140between the flanges1032a,1032bin the channel1034. A rotation collar1160(similar to the rotation collar1050described above with reference toFIG. 69) captures the flange1040on the compression housing1030. As described above, the compression cable1048is coupled to the compression housing1030by attachment pin1044.

During a surgical procedure, the surgeon may withdraw each of the flexible members1106,1108from the end effector1100. Doing so pulls the anvil1102toward the cartridge1104to compress the tissue therebetween. As set forth above, the surgeon may be unable to apply sufficient compressive pressure to sufficiently collapse the tissue between the anvil1102and the cartridge1104with the flexible members1106,1108alone. The surgeon may apply additional compressive pressure by engaging the compression mechanism1120, including each of the distal clamping mechanism1134and the proximal clamping mechanism1136.

To do so, and with reference toFIGS. 72A and 72B, when the anvil1102is proximate the cartridge1104in a position in which the compression wedges1138,1140are positioned to be engaged by the distal cam tube1150and the rotation collar1160, respectively, the surgeon may tension the compression cable1048to forcibly engage the wedge surface1144of the compression wedge1140with the rotation collar1160. At the proximal end1110, tensioning the compression cable1048pulls the compression housing1030within the rotation collar1160and engages the rotation collar1160with the wedge surface1144. Forcible engagement between the wedge surface1144and the rotation collar1160forces the anvil1102toward the cartridge1104. At the distal end1112, tensioning the compression cable1048pulls the cam tube1150toward the compression wedge1138to forcibly engage the cam tube1150with the wedge surface1142. Forcible engagement between the wedge surface1142and the cam tube1150forces the anvil1102toward the cartridge1104. In this way, additional compressive pressures may be applied at each end of the end effector1100. In the exemplary embodiment shown, the articulation mechanism1130may be substantially similar to the articulation mechanism970described above with reference toFIG. 69-70B.

While the present invention has been illustrated by a description of various preferred embodiments and while these embodiments have been described in some detail, it is not the intention of the inventor to restrict or in any way limit the scope of the appended claims to such detail. Though the embodiments described herein were primarily directed to a resection line guide, it is clear that many of the aspects of the present invention may be utilized with additional devices. By way of example, the embodiments described herein may operate as a surgical clamp or a stabilizing device independent of the aspects of the present invention that allow the embodiments to act as an endocutter stapling device or a component thereof. Additional advantages and modifications will readily appear to those skilled in the art. The various features of the invention may be used alone or in any combination depending on the needs and preferences of the user.