Surgical instrument with integral knife blade

A cartridge of a surgical instrument includes a housing, a lead screw mounted for rotation in the housing, a drive member operatively coupled with the lead screw, and a knife member. The knife member is driven distally by the drive member and is configured to cut when moved distally. During an initial distal movement of the drive member, the knife member is coupled with the housing to restrain the knife member from moving distally. Subsequent to the initial distal movement of the drive member, the drive member drives the knife member toward the distal end.

BACKGROUND

Minimally invasive surgical techniques are aimed at reducing the amount of extraneous tissue that is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. As a consequence, the average length of a hospital stay for standard surgery may be shortened significantly using minimally invasive surgical techniques. Also, patient recovery times, patient discomfort, surgical side effects, and time away from work may also be reduced with minimally invasive surgery.

A common form of minimally invasive surgery is endoscopy, and a common form of endoscopy is laparoscopy, which is minimally invasive inspection and surgery inside the abdominal cavity. In standard laparoscopic surgery, a patient's abdomen is insufflated with gas, and cannula sleeves are passed through small (approximately one-half inch or less) incisions to provide entry ports for laparoscopic instruments.

Laparoscopic surgical instruments generally include an endoscope (e.g., laparoscope) for viewing the surgical field and tools for working at the surgical site. The working tools are typically similar to those used in conventional (open) surgery, except that the working end or end effector of each tool is separated from its handle by an extension tube (also known as, e.g., an instrument shaft or a main shaft). The end effector can include, for example, a clamp, grasper, scissor, stapler, cautery tool, linear cutter, or needle holder.

To perform surgical procedures, the surgeon passes working tools through cannula sleeves to an internal surgical site and manipulates them from outside the abdomen. The surgeon views the procedure from a monitor that displays an image of the surgical site taken from the endoscope. Similar endoscopic techniques are employed in, for example, arthroscopy, retroperitoneoscopy, pelviscopy, nephroscopy, cystoscopy, cisternoscopy, sinoscopy, hysteroscopy, urethroscopy, and the like.

Minimally invasive telesurgical robotic systems are being developed to increase a surgeon's dexterity when working on an internal surgical site, as well as to allow a surgeon to operate on a patient from a remote location (outside the sterile field). In a telesurgery system, the surgeon is often provided with an image of the surgical site at a control console. While viewing a three dimensional image of the surgical site on a suitable viewer or display, the surgeon performs the surgical procedures on the patient by manipulating master input or control devices of the control console. Each of the master input devices controls the motion of a servo-mechanically actuated/articulated surgical instrument. During the surgical procedure, the telesurgical system can provide mechanical actuation and control of a variety of surgical instruments or tools having end effectors that perform various functions for the surgeon, for example, holding or driving a needle, grasping a blood vessel, dissecting tissue, or the like, in response to manipulation of the master input devices.

Manipulation and control of these end effectors is a particularly beneficial aspect of robotic surgical systems. For this reason, it is desirable to provide surgical tools that include mechanisms that provide three degrees of rotational movement of an end effector to mimic the natural action of a surgeon's wrist. Such mechanisms should be appropriately sized for use in a minimally invasive procedure and relatively simple in design to reduce possible points of failure. In addition, such mechanisms should provide an adequate range of motion to allow the end effector to be manipulated in a wide variety of positions.

Surgical clamping and cutting instruments (e.g., non-robotic linear clamping, stapling, and cutting devices, also known as surgical staplers; and electrosurgical vessel sealing devices) have been employed in many different surgical procedures. For example, a surgical stapler can be used to resect a cancerous or anomalous tissue from a gastro-intestinal tract. Many known surgical clamping and cutting instruments, including known surgical staplers, have opposing jaws that clamp tissue and an articulated knife to cut the clamped tissue.

Surgical clamping and cutting instruments are often deployed into restrictive body cavities (e.g., through a cannula to inside the pelvis). Accordingly, it is desirable for a surgical clamping and cutting instrument to be both compact and maneuverable for best access to and visibility of the surgical site. Known surgical clamping and cutting instruments, however, may fail to be both compact and maneuverable. For example, known surgical staplers may lack maneuverability with respect to multiple degrees of freedom (e.g., Roll, Pitch, and Yaw) and associated desired ranges of motion. Typically, known surgical staplers have a smaller range of Pitch motion than desirable and no Yaw motion.

Additionally, surgical clamping and cutting instruments can sometimes fail to fully actuate (e.g., due to a hard obstacle blocking the knife path). In such an event, it is desirable that the knife blade not be in a position that may represent a hazard with respect to removal of the surgical instrument from the surgical site. Known surgical clamping and cutting instruments, however, may fail to avoid the potential knife hazard and at the same time be compact and maneuverable.

Thus, there is believed to be a need for improved surgical clamping and cutting instruments and related methods. Such surgical clamping and cutting instruments should be compact and maneuverable, and employ a knife that does not represent a hazard with respect to removal of the surgical instrument from the surgical site when the surgical instrument fails to fully actuate.

BRIEF SUMMARY

Improved surgical clamping and cutting instruments (e.g., surgical staplers, and electrosurgical vessel sealing devices) and related methods are disclosed. Surgical clamping and cutting instruments described herein employ a proximal to distal knife movement, thereby orienting the knife to greatly reduce the likelihood of unintentionally cutting tissue while removing the surgical instrument from the surgical site in the event that the surgical instrument fails to fully actuate. Surgical clamping and cutting instruments described herein locate the knife and associated drive mechanism distal to the wrist of the surgical instrument, thereby permitting the use of a high motion wrist to provide high maneuverability. And surgical clamping and cutting instruments described herein employ relative movement between the drive mechanism and the knife, thereby reducing the length of the surgical instrument.

Thus, in one aspect, a method of articulating a cutting blade in a surgical instrument is disclosed. The method includes supporting a knife member having a cutting blade within a housing of the surgical instrument. The housing has a proximal end and a distal end. The cutting blade is configured to cut when the knife member is moved distally. A drive member is moved distally through a first movement from a first position to a second position. The knife member is coupled with the housing during the first movement of the drive member, thereby restraining the knife member from moving distally. The drive member is used to drive the knife member distally during a second distal movement of the drive member from the second position to a third position.

The knife member can be restrained from moving distally throughout a movement of the drive member distally. For example, the knife member can be restrained from moving distally throughout an approximate 4 mm movement of the drive member distally.

In many embodiments, the act of coupling the knife member with the housing includes using the drive member to secure engagement between the knife member and the housing. For example, the drive member can be interfaced with the knife member to secure engagement between the knife member and the housing. In many embodiments, the knife member includes a first protrusion that interfaces with the drive member and a receptacle of the housing to restrain the knife member during the first movement of the drive member from moving distally. The knife member can be rotated to remove the first protrusion from the housing receptacle. The first protrusion can be received within a receptacle of the drive member. And the first protrusion can be accommodated in the drive member receptacle during the second movement of the drive member.

In many embodiments, the knife member includes a drive feature that does not interface with the drive member during the first movement of the drive member and interfaces with the drive member during the second movement of the drive member. In many embodiments, the knife drive feature includes a second protrusion.

In many embodiments, the knife member is rotated near the end of the actuation stroke to lower the cutting blade into the housing. For example, the knife member can be driven along a cam surface thereby raising a distal end of the knife member and lowering the cutting blade into the housing.

In many embodiments, the drive member is used to provide additional functionality. For example, the method can include using the drive member to deploy staples during the second movement of the drive member.

In another aspect, a surgical instrument is disclosed. The surgical instrument includes an elongated shaft having a shaft distal end and a shaft proximal end, an end effector coupled to the shaft distal end and including opposed jaws, a housing included in one of the jaws, a knife member, and a drive member. The housing includes a housing proximal end, a housing distal end, an upper surface extending between the housing proximal and distal ends, a central cavity extending between the housing proximal and distal ends, and a longitudinal slot extending through the upper surface. The knife member is supported within the housing for movement distally. The knife member has a cutting blade configured to cut when the knife member is moved distally. The drive member is slidably mounted in the housing for movement distally. The knife member is coupled with the housing during a first movement of the drive member distally from a first position to a second position to restrain the knife from moving distally. The knife member is driven distally by the drive member during a second movement of the drive member distally from the second position to a third position.

The knife member of the surgical instrument can be restrained from moving distally through the first movement of the drive member distally. For example, the knife member can be restrained from moving distally throughout an approximate 4 mm movement of the drive member distally.

In many embodiments, the drive member is used to secure engagement between the knife member and the housing during the first movement of the drive member to restrain the knife member from moving distally. For example, the drive member can be interfaced with the knife member to secure engagement between the knife member and the housing. In many embodiments, the knife member includes a first protrusion that interfaces with the drive member and a receptacle of the housing to restrain the knife member during the first movement of the drive member from moving distally. The knife member can be rotated to remove the first protrusion from the housing receptacle. The first protrusion can be received within a receptacle of the drive member. And the first protrusion can be accommodated in the drive member receptacle during the second movement of the drive member.

In many embodiments, the knife member includes a drive feature that does not interface with the drive member during the first movement of the drive member and interfaces with the drive member during the second movement of the drive member. In many embodiments, the knife drive feature includes a second protrusion.

In many embodiments, the knife member is rotated near the end of the actuation stroke to lower the cutting blade into the housing. For example, the housing can include a cam surface configured to interface with the knife member to raise a distal end of the knife member to lower the cutting blade into the housing as the drive member is moved distally through a third movement from the third position to a fourth position.

In many embodiments, the surgical instrument is configured to perform an additional function. For example, the housing can include a plurality of staple openings extending between the upper surface and the central cavity. The surgical instrument can further include a plurality of staples disposed in the staple openings. Each of the staples can be deployed in response to a movement of the drive member distally.

In another aspect, a demountably attachable cartridge of a surgical instrument is disclosed. The cartridge includes a housing demountably attachable to an end effector of the surgical instrument, a lead screw coupled with the housing for rotation relative to the housing, a rotary input rotationally coupled with the lead screw, a knife member, and a drive member mounted in the housing and coupled with the lead screw for movement along the lead screw in response to rotation of the lead screw. The housing includes a proximal end, a distal end, an upper surface extending between the proximal and distal ends, a central cavity between the housing proximal and distal ends, and a longitudinal slot extending through the upper surface. The rotary input is configured to couple with a rotary output of the surgical instrument when the housing is attached to the end effector. The knife member is supported within the housing for movement distally. The knife member is coupled with the housing during a first movement of the drive member distally from a first position to a second position to restrain the knife from moving distally. The knife member is driven distally by the drive member during a second movement of the drive member distally from the second position to a third position.

In many embodiments, the cartridge is configured to perform an additional function. For example, the housing can include a plurality of staple openings extending between the upper surface and the central cavity. The cartridge can further include a plurality of staples disposed in the staple openings. Each of the staples can be deployed in response to a movement of the drive member distally.

For a fuller understanding of the nature and advantages of the present invention, reference should be made to the ensuing detailed description and accompanying drawings. Other aspects, objects and advantages of the invention will be apparent from the drawings and detailed description that follows.

DETAILED DESCRIPTION

Minimally Invasive Robotic Surgery

Referring now to the drawings, in which like reference numerals represent like parts throughout the several views,FIG. 1is a plan view illustration of a Minimally Invasive Robotic Surgical (MIRS) system10, typically used for performing a minimally invasive diagnostic or surgical procedure on a Patient12who is lying down on an Operating table14. The system can include a Surgeon's Console16for use by a Surgeon18during the procedure. One or more Assistants20may also participate in the procedure. The MIRS system10can further include a Patient Side Cart22(surgical robot) and an Electronics Cart24. The Patient Side Cart22can manipulate at least one removably coupled tool assembly26(hereinafter simply referred to as a “tool”) through a minimally invasive incision in the body of the Patient12while the Surgeon18views the surgical site through the Console16. An image of the surgical site can be obtained by an endoscope28, such as a stereoscopic endoscope, which can be manipulated by the Patient Side Cart22to orient the endoscope28. The Electronics Cart24can be used to process the images of the surgical site for subsequent display to the Surgeon18through the Surgeon's Console16. The number of surgical tools26used at one time will generally depend on the diagnostic or surgical procedure and the space constraints within the operating room among other factors. If it is necessary to change one or more of the tools26being used during a procedure, an Assistant20may remove the tool26from the Patient Side Cart22, and replace it with another tool26from a tray30in the operating room.

FIG. 2is a perspective view of the Surgeon's Console16. The Surgeon's Console16includes a left eye display32and a right eye display34for presenting the Surgeon18with a coordinated stereo view of the surgical site that enables depth perception. The Console16further includes one or more input control devices36, which in turn cause the Patient Side Cart22(shown inFIG. 1) to manipulate one or more tools. The input control devices36can provide the same degrees of freedom as their associated tools26(shown inFIG. 1) to provide the Surgeon with telepresence, or the perception that the input control devices36are integral with the tools26so that the Surgeon has a strong sense of directly controlling the tools26. To this end, position, force, and tactile feedback sensors (not shown) may be employed to transmit position, force, and tactile sensations from the tools26back to the Surgeon's hands through the input control devices36.

The Surgeon's Console16is usually located in the same room as the patient so that the Surgeon may directly monitor the procedure, be physically present if necessary, and speak to an Assistant directly rather than over the telephone or other communication medium. However, the Surgeon can be located in a different room, a completely different building, or other remote location from the Patient allowing for remote surgical procedures.

FIG. 3is a perspective view of the Electronics Cart24. The Electronics Cart24can be coupled with the endoscope28and can include a processor to process captured images for subsequent display, such as to a Surgeon on the Surgeon's Console, or on another suitable display located locally and/or remotely. For example, where a stereoscopic endoscope is used, the Electronics Cart24can process the captured images to present the Surgeon with coordinated stereo images of the surgical site. Such coordination can include alignment between the opposing images and can include adjusting the stereo working distance of the stereoscopic endoscope. As another example, image processing can include the use of previously determined camera calibration parameters to compensate for imaging errors of the image capture device, such as optical aberrations.

FIG. 4diagrammatically illustrates a robotic surgery system50(such as MIRS system10ofFIG. 1). As discussed above, a Surgeon's Console52(such as Surgeon's Console16inFIG. 1) can be used by a Surgeon to control a Patient Side Cart (Surgical Robot)54(such as Patent Side Cart22inFIG. 1) during a minimally invasive procedure. The Patient Side Cart54can use an imaging device, such as a stereoscopic endoscope, to capture images of the procedure site and output the captured images to an Electronics Cart56(such as the Electronics Cart24inFIG. 1). As discussed above, the Electronics Cart56can process the captured images in a variety of ways prior to any subsequent display. For example, the Electronics Cart56can overlay the captured images with a virtual control interface prior to displaying the combined images to the Surgeon via the Surgeon's Console52. The Patient Side Cart54can output the captured images for processing outside the Electronics Cart56. For example, the Patient Side Cart54can output the captured images to a processor58, which can be used to process the captured images. The images can also be processed by a combination the Electronics Cart56and the processor58, which can be coupled together to process the captured images jointly, sequentially, and/or combinations thereof. One or more separate displays60can also be coupled with the processor58and/or the Electronics Cart56for local and/or remote display of images, such as images of the procedure site, or other related images.

FIGS. 5A and 5Bshow a Patient Side Cart22and a surgical tool62, respectively. The surgical tool62is an example of the surgical tools26. The Patient Side Cart22shown provides for the manipulation of three surgical tools26and an imaging device28, such as a stereoscopic endoscope used for the capture of images of the site of the procedure. Manipulation is provided by robotic mechanisms having a number of robotic joints. The imaging device28and the surgical tools26can be positioned and manipulated through incisions in the patient so that a kinematic remote center is maintained at the incision to minimize the size of the incision. Images of the surgical site can include images of the distal ends of the surgical tools26when they are positioned within the field-of-view of the imaging device28.

Tissue Gripping End Effectors

FIG. 6shows a surgical tool70that includes a proximal chassis72, an instrument shaft74, and a distal end effector76having a jaw78that can be articulated to grip a patient tissue. The proximal chassis includes input couplers that are configured to interface with and be driven by corresponding output couplers of the Patient Side Cart22. The input couplers are drivingly coupled with drive shafts that are disposed within the instrument shaft74. The drive shafts are drivingly coupled with the end effector76.

Linear Stapling and Cutting Surgical Instruments

FIG. 7shows a demountably attachable cartridge100of a linear stapling and cutting surgical instrument, in accordance with many embodiments. The cartridge100is configured to removably attach to a jaw of an end effector. The cartridge has a proximal end102that is attached to the jaw of the end effector and a distal end104disposed at a corresponding distal end of the jaw of the end effector. The cartridge100includes six rows of staple openings106, a longitudinal slot108, a proximal knife garage110, a distal knife garage112, and a rotational input114. In many embodiments, a staple is disposed in each of the staple openings for deployment there from. The longitudinal slot108accommodates a cutting blade of a knife member (not shown) extending there from as the knife member is moved from the proximal knife garage110to the distal knife garage112. In operation, the staples are deployed starting at the cartridge proximal end102and proceeding to the cartridge distal end104. The cutting blade is moved to trail the stapling of the tissue to ensure that only fully stapled tissue is cut.FIG. 8shows the cartridge100with an attached staple retainer116, which is removed prior to using the cartridge100.

FIG. 9is a cross-sectional view showing details of the attachment of the cartridge100to an end effector118, in accordance with many embodiments. The end effector118includes a lower jaw120, an upper jaw122, a two degree of freedom wrist124, a rotationally-driven clamping mechanism126, and a spring loaded coupling128. The lower jaw120is configured to accommodate and support the cartridge100, as well as position the cartridge100relative to the spring loaded coupling128. The upper jaw122is pivotally coupled with the lower jaw120to articulate relative to the lower jaw120to clamp tissue. The upper jaw122includes staple forming recesses configured and positioned relative to the staple openings106to form the staples into a “B” shape upon deployment of the staples.

The two degree of freedom wrist124provides for attachment of the end effector118to an elongated instrument shaft130for articulation of the end effector118about two orthogonal axes relative to the instrument shaft130. Details of a suitable two degree of freedom wrist that can be used are disclosed in U.S. application Ser. No. 12/945,748, entitled “SURGICAL TOOL WITH A TWO DEGREE OF FREEDOM WRIST,” filed Nov. 12, 2010, the full disclosure of which is hereby incorporated herein by reference.

The rotationally-driven clamping mechanism126actuates the upper jaw122relative to the lower jaw120to securely clamp tissue between the upper and lower jaws. The clamping mechanism126is rotationally driven by a first drive shaft132disposed internal to the instrument shaft130. Details of a suitable rotationally-driven clamping mechanism that can be used are disclosed in U.S. application Ser. No. 12/945,541, entitled “END EFFECTOR WITH REDUNDANT CLOSING MECHANISMS,” filed Nov. 12, 2010, the full disclosure of which is hereby incorporated herein by reference.

The spring-loaded coupling128rotationally couples a lead screw134of the cartridge100with an extension shaft136, which is driven by a second drive shaft138disposed internal to the instrument shaft130. The spring-loaded coupling128includes a coil spring140and a coupling fitting142. In the embodiment shown, the coupling fitting142employs a three-lobe spline receptacle that interfaces with three-sided external surfaces of the rotational input114and of the extension shaft136. The spring-loaded coupling142accommodates angular misalignment of the three-lobe spline that might occur when cartridge100is installed into end effector118. The spring-loaded coupling142fully engages the three-lobe spline when rotated into angular alignment. Rotation of the lead screw134is used to translate a drive member144of the cartridge100. The resulting motion of the drive member144is used to deploy the staples and to distally advance a knife member146of the cartridge100to cut the clamped tissue down the center of the rows of deployed staples.

The end effector118includes a first universal joint assembly148and a second universal joint assembly150. The first universal joint assembly148rotationally couples the clamping mechanism126to the first drive shaft132. The second universal joint assembly150rotationally couples the extension shaft136to the second drive shaft138. Each of the first and second universal joint assemblies148,150is configured to transmit torque through a range of angles suitable to the range of Pitch and Yaw of the end effector118relative to the instrument shaft130. Details of a suitable universal joint assembly that can be used are disclosed in U.S. application Ser. No. 12/945,740, entitled “DOUBLE UNIVERSAL JOINT,” filed Nov. 12, 2010, the full disclosure of which is hereby incorporated herein by reference.

The first and second drive shafts132,138are disposed offset to the centerline of the instrument shaft130, which may be independently rotated. Details of a suitable drive mechanism that can be used to actuate the first and second drive shafts132,138are disclosed in U.S. application Ser. No. 12/945,461, entitled “MOTOR INTERFACE FOR PARALLEL DRIVE SHAFTS WITHIN AN INDEPENDENTLY ROTATING MEMBER,” filed Nov. 12, 2010, the full disclosure of which is hereby incorporated herein by reference.

FIG. 10is an exploded perspective view illustrating components of the cartridge100. The illustrated components include the retainer116,66staples152, a printed circuit assembly (PCA) spring154, a PCA156, a cartridge body158,22staple pushers160, the knife member146, the lead screw134, the drive member144, a thrust washer162, a lead screw nut164, and a cover166. The cartridge body158has the66staple openings106arranged in 6 rows, with 3 rows of the staple openings106being disposed on each side of the longitudinal slot108. The retainer116is removably attachable to the cartridge100and covers the staple openings106to retain the staples152prior to use of the cartridge100. The staple pushers160interface with the staples152and slidingly interface with the cartridge body158. Motion of the drive member144along the lead screw134results in engagement of the staple pushers160by distally-facing ramp surfaces176of the drive member144to drive the staple pushers160up relative to the cartridge body158to deploy the staples152as the drive member144moves towards the distal end104. The knife member146includes proximal protrusions168and distal protrusions170. The cover166is attached to the cartridge body158.

FIGS. 11A and 11Bfurther illustrate the PCA156and the PCA spring154. The PCA spring154interfaces with the cartridge body158and retains the PCA156. The PCA spring154includes PCA spring hooks172, which latch onto the cartridge body158to retain the PCA spring154. When the cartridge100is attached to the end effector118, instrument pins174of the end effector118slide beneath and lift the PCA156, thereby electrically connecting the PCA156with the instrument pins174and allowing for the use of increased associated tolerances. This arrangement however is not critical, as long as the instrument pins174make suitable contact with the PCA156. Accordingly, in some embodiments, the PCA156can be turned on edge such that the shown chip is out of the load path. The PCA156can be used to electronically store identification, configuration, and/or use information associated with the cartridge100.

The cartridge100can be assembled using the following assembly sequence. First, with the cartridge body158in a “bottom up” orientation, the staple pushers160are installed into the staple openings106. Next, the knife member146is installed into the proximal garage110with proximal protrusions168of the knife member146placed into proximal receptacles in the cartridge body158. Next, the drive member144, the thrust washer162, and the lead screw nut164are installed onto the lead screw134and the lead screw nut134is laser welded flush to the end of the lead screw134. The resulting lead screw assembly is then installed into the cartridge body158with the drive member144positioned at the proximal end of the lead screw134. Next, the cover166is installed onto the cartridge body158. The resulting assembly can then be lubricated, for example, by immersing the resulting assembly into a lubricant. Next, the assembly is flipped to a “top up” orientation and the PCA156is installed. Next, the PCA spring154is pushed onto the cartridge body158until the PCA spring hooks172latch. Next, the staples152are installed into the staple openings106and the retainer116is then installed. Finally, data is installed into the PCA156.

FIG. 12illustrates components of the cartridge100related to the actuation of the knife member146from a starting position (illustrated) in which the knife member146is shielded by the proximal garage110to an ending position (not illustrated) in which the knife member146is shielded by the distal garage112. The lead screw134is mounted for rotation relative to the cartridge body158and extends along the length of the cartridge body158. The drive member144is internally threaded and is coupled with the lead screw134and slidably mounted in the cartridge body158for translation along the lead screw134in response to rotation of the lead screw134. The drive member144includes one or more distally-facing ramps176configured to engage the staple pushers160as the drive member144is advanced toward the distal end104of the cartridge body100. The knife member146includes a cutting blade178, the body portion180, the proximal protrusions168extending from opposite sides of the body portion180, and the proximal protrusions170also extending from opposite sides of the body portion180. As will be described in more detail below, when the drive member144is advanced distally from its illustrated starting position, the knife member146remains stationary relative to the cartridge body158until the drive member144contacts the distal protrusions170by which the knife member146is then driven distally by the drive member144. Near the end of the distal travel of the drive member144, the distal end of the knife member146is driven along a cam surface182of the cartridge body158, thereby raising the distal end of the knife member146to lower the cutting blade178below an upper surface184of the cartridge body158and into the distal garage112. The knife member body portion180is constrained by opposing surfaces of the cartridge body158that define the longitudinal slot108. The knife proximal and distal protrusions168,170extend from opposite sides of the knife member body portion180beyond the width of the longitudinal slot108, thereby serving to constrain the knife member146vertically relative to the cartridge body158and the drive member144.

FIGS. 13A through 13Cshows staple deployment related components of a linear stapling and cutting surgical instrument having four rows of staples, in accordance with many embodiments. Similar to the cartridge100, an internally-threaded drive member144-4is coupled with a lead screw134and slidably mounted in a cartridge body (not shown) for translation along the lead screw134in response to rotation of the lead screw134. The drive member144-4includes distally facing bi-linear ramps176-4, which engage staple pushers160-4as the drive member144-4is advanced distally along the lead screw134. Each of the staple pushers160-4is configured to push a single staple (not shown). Each of the staple pushers160-4has bi-linear ramp surfaces186-6, which are configured to interface with the correspondingly sloped bi-linear ramps176-4of the drive member144-4. Each of the staple pushers160-4has end portions188-4that are shaped to slidingly interface with staple openings in the cartridge body.

The drive member144-4is configured to accommodate and interface with the knife member146to initially move distally relative to the knife member146, then drive the knife member146toward the distal end of the cartridge body and push the distal end of the knife member146up the distal ramp182of the cartridge body158. The drive member144-4features that interface with the knife member146include a central slot190, proximal receptacles192, top surfaces194, and distal surfaces196. The central slot190accommodates the knife body portion180throughout the stroke of the knife member146from its starting position in the proximal garage110to its ending position in the distal garage112. The proximal receptacles192accommodate the knife member proximal protrusions168while the knife member146is driven distally by the drive member144-4. The top surfaces194interface with the proximal protrusions168to secure engagement between the proximal protrusions168and receptacles in the cartridge body158during the initial distal movement of the drive member144-4in which the drive member144-4is moved distally relative to both the cartridge body158and the knife member146and the knife member146is held stationary relative to the cartridge body158via the engagement between the proximal protrusions168and the associated cartridge body receptacles. After the initial relative distal movement of the drive member144-4relative to the knife member146, the drive member distal surfaces196interface with the knife member distal protrusions170to drive the knife member146distally and, in conjunction with surfaces of the cartridge body158on both sides of the longitudinal slot108, control the vertical position of the distal protrusions170as the knife member146is driven distally. When the distal portion of the knife member146is driven up the cam surface182, the distal protrusions170separate from the distal surfaces196and the knife member146is then driven by a proximal wall of the drive member proximal receptacles192, which interface with the knife member proximal protrusions168to drive the knife member146along the cam surface182, thereby stowing the cutting blade178into the distal garage112.

FIG. 14Ashows a distal end of the cartridge body158.FIG. 14Bshows a top view and a perspective view of one of the staple pushers160. As illustrated, the staple openings106and the staple pushers160have complementary shapes such that each of the staple pushers160is accommodated within one of the staple openings106for translation within the staple opening106in response to being driven by the drive member144as the drive member144is translated toward the cartridge distal end104.

FIGS. 14C through 14Hprovide additional illustration of the drive member144.FIG. 14Cshows a perspective view of the drive member144.FIG. 14Dshows a top view of the drive member144.FIG. 14Eshows a side view of the drive member144.FIG. 14Fshows a distal end view of the drive member144.FIG. 14Gshows cross-sectional view AA as defined inFIG. 14D. AndFIG. 14Hshows cross-sectional view BB as defined inFIG. 14D.

FIGS. 15A through 15Cprovide additional illustration of the knife member146. In many embodiments, the cutting blade178is formed integral to the knife member body portion180. The proximal protrusions168and the distal protrusions170can be integral with the knife member body portion180, or Ruined by press-fitting pins into transverse holes in the knife-member body portion180. The body portion180and the pins can be formed from a suitable material(s), for example, 17-4 PH, 440A, or 420 stainless steels. The cutting blade178is beveled to a ground edge on both sides, but can be flat with a ground edge, or beveled only on one side while ground on the other. Additional honing can be performed to create multiple angles on each side of the cutting blade178.

The configuration of the knife member146provides robust support of the cutting blade178, which may be particularly advantageous when the cutting blade178is used to cut through something other than soft tissue. For example, it may occur that the cartridge100is used to install staples through previously stapled tissue, thereby possibly placing an existing staple in the path of the cutting blade178so that the existing staple must be cut by the cutting blade178.

FIG. 15Dillustrates an alternative configuration of the knife member146. In many embodiments, the knife member has a cutting blade178with a hooked tip179. The hooked tip is blunted and protrudes well distally past, and well laterally above, the top-most cutting edge of the cutting blade. The hooked tip179can help ensure that a full thickness of tissue is cut by preventing tissue from climbing over the height of the cutting blade178. The hooked tip can also reduce the risk of injury to operating room staff in case a device failure leaves the cutting blade178exposed.

FIG. 15Eillustrates another alternative configuration of the knife member146. In many embodiments, the knife member has a cutting blade178with a blunted tip181. The blunted tip protrudes slightly distally past (or is collinear with), but well laterally above, the top-most cutting edge of the cutting blade179. Like the hooked tip179of the cutting blade178ofFIG. 15D, the blunted tip181of cutting blade179can help prevent tissue climb-over and reduce risk of accidental injury.

FIG. 15Fillustrates another alternative configuration of the knife member146. In many embodiments, the knife member has a curved cutting blade183with a blunted tip. The blunted tip protrudes slightly distally past (or is collinear with), but well laterally above, the top-most cutting edge of the cutting blade183. The blunted tip of curved cutting blade183can help prevent tissue climb-over and reduce risk of accidental injury. The curved cutting blade183can also help further that purpose by gathering and centering tissue within its center-most portion. This can also help prevent tissue from clogging the lower-most blade/cartridge interface via the centering action. The cutting blade183is beveled to a ground edge on both sides, but can be flat with a ground edge, or beveled only on one side while ground on the other. Additional honing can be performed to create multiple angles on each side of the cutting blade183.

FIG. 15Gillustrates another alternative configuration of the knife member146. In many embodiments, the knife member has a curved cutting blade185, which is largely identical to the curved cutting blade183ofFIG. 15F, and thus shares the same features. However, the curved cutting blade185does not include a blunted tip, since in some applications the curvature of the cutting blade185alone can prevent tissue from climbing-over.

FIG. 15Hillustrates another alternative configuration of the knife member146. Here, the knife member146is formed with integral pins187extending laterally on one side. The pins187respectively provide male coupling surfaces for attaching the knife member146to other portions of the cartridge100in a similar manor to pins168and170ofFIG. 15C. The pins187can be formed, for example, by: stamping a singular piece of source material to form the knife member146integrally with the pins187; welding/pressing/bonding the pins187into a separate knife member146; or by molding (with additional forging as needed) the knife member146integrally with the pins187. The pins187can also extend from both sides of the knife member146, on the side opposite as shown, or the pins can extend from each side of the knife member146at different or the same proximal and distal portions of the knife member146. Indented surfaces189forming blind holes may also be formed opposite the pins by the above processes or later machined into the knife member. The indented surfaces189respectively provide female coupling surfaces for attaching the knife member146to other portions of the cartridge100. It should be understood that this pin configuration can apply to any of the blade designs disclosed herein.

FIGS. 16A through 16Dillustrate the interaction of components of the cartridge100during the actuation of the knife member146from its starting position in the proximal garage110to its final position in the distal garage112.FIG. 16Ashows three different positions of the knife member146relative to the cartridge body158, specifically a starting proximal-most position, an intermediate position, and a distal position just before the distal end of the knife member146is driven up the cartridge body cam surface182.

As shown inFIGS. 16A and 16B, in the starting proximal-most position, the drive member144is positioned at the proximal end of the lead screw134and the knife member proximal protrusions168are disposed within receptacles198in the cartridge body158. The drive member upper surfaces194interface with the knife member proximal protrusions168to retain the proximal protrusions168in the cartridge body receptacles198, thereby securing engagement between the proximal protrusions168and the cartridge body receptacles198. The distal end of the knife is trapped between a central cavity ceiling200of the cartridge body158and the lead screw134and the knife member body portion180is disposed within the longitudinal slot108, thereby restraining the knife member146in a substantially fixed position and orientation relative to the cartridge body158.

From the starting proximal-most position, rotation of the lead screw134drives the drive member144distally along the lead screw134. Throughout a starting “lost-motion” portion of the distal motion of the drive member144along the lead screw134, the proximal protrusions168remain trapped in the cartridge body receptacles198by the drive member upper surfaces194. When the drive member144has moved distally to a point where the drive member distal surfaces196contact the knife member distal protrusions170, the drive member proximal receptacles192are disposed below the cartridge body receptacles198, thereby permitting the knife member146to rotate to transfer the proximal protrusions168from the cartridge body receptacles198to the drive member proximal receptacles192. To facilitate this transfer, a distal surface202of the cartridge body receptacles198is sloped as illustrated to enhance the transfer by imparting a downward force component on the proximal protrusions168as the knife member distal surfaces196drive the knife member146distally via contact with the knife member distal protrusions170.

FIG. 16Cillustrates interaction between the drive member144, the knife member146, and the cartridge body158following the “lost motion” portion of the distal motion of the drive member144along the lead screw134. After the drive member distal surfaces196come into contact with the knife member distal protrusions170causing the knife member146to rotate to transfer the proximal protrusions168into the drive member proximal receptacles192, continued rotation of the lead screw134results in continued distal motion of the drive member144and corresponding distal motion of the knife member146. During this continued distal motion, the knife member146is constrained by both the drive member146and the ceiling200of the cartridge body158.

FIGS. 16A and 16Dillustrate interaction between the drive member144, the knife member146, and the cartridge body158(particularly the cam surface182of the cartridge body158) during a terminal portion of the distal motion of the drive member144along the lead screw134. As the drive member144is advanced distally near the end of its travel along the lead screw134, the distal end of the knife member146comes into contact with the cam surface182and is subsequently driven along the cam surface182until reaching the ending distal-most position illustrated inFIG. 16Din which the drive member144has reached the end of its travel along the lead screw134. As a result of the distal end of the knife member146being driven along the upward sloping cam surface182, the knife member146rotates approximately around the knife member proximal protrusions168, thereby lowering the cutting blade178into the distal garage112.

Linear Stapling and Cutting Methods

FIG. 17shows acts of a method210of deploying staples from and of articulating a cutting blade in a linear stapling and cutting surgical instrument, in accordance with many embodiments. Any suitable linear stapling and cutting surgical instrument can be used to practice the method210. For example, the linear stapling and cutting surgical instruments and cartridges described herein can be used to practice the method210.

In act212, a knife member having a cutting blade is supported within a housing of a linear stapling and cutting surgical instrument. The housing has a proximal end and a distal end. The cutting blade is configured to cut when the knife member is moved distally. In act214, a drive member is moved distally through a first movement from a first position to a second position.

In act216, the knife member is coupled with the housing during the first movement of the drive member to restrain the knife member from moving distally. In many embodiments, the knife member is restrained from moving distally throughout an approximate 4 mm movement of the drive member distally. In many embodiments, coupling the knife member with the housing includes using the drive member to secure engagement between the knife member and the housing. In many embodiments, using the drive member to secure engagement between the knife member and the housing includes interfacing the drive member with the knife member. For example, the knife member can include a first protrusion that interfaces with the drive member and a receptacle of the housing to restrain the knife member during the first movement of the drive member from moving distally.

In act218, the drive member is used to drive the knife member distally during a second distal movement of the drive member from the second position to a third position. In many embodiments, the knife member includes a drive feature that does not interface with the drive member during the first movement of the drive member and interfaces with the drive member during the second movement of the drive member. In many embodiments, the knife drive feature includes a second protrusion.

In act220, the drive member is used to deploy staples during the second movement of the drive member. For example, the drive member can include ramp surfaces that interface with staple pushers, which deploy the staples.

FIG. 18shows optional acts that can be accomplished in the method210, in accordance with many embodiments. In optional act222, the knife member is rotated to remove the first protrusion from the housing receptacle. In optional act224, the first protrusion is received into a receptacle of the drive member. In optional act226, the first protrusion is accommodated in the drive member receptacle during the second movement of the drive member. And in optional act228, the knife member is driven along a cam surface thereby raising a distal end of the knife member and lowering the cutting blade into the housing.

The methods disclosed herein can be employed in any suitable application. For example, the methods disclosed herein can be employed in surgical instruments, manual or powered, hand-held or robotic, directly controlled or teleoperated, for open or minimally invasive (single or multi-port) procedures.