Compression and firing force sensors for circular surgical staplers

Abstract

A surgical instrument includes a housing assembly, a movable member, an anvil, and a force sensing assembly. The housing assembly includes a first housing, a second housing, and a deck surface including at least one annular array of staple openings. The force sensing assembly includes at least one of a compression force sensor disposed between the first housing and the second housing or a tension force sensor coupled with the movable member or the anvil. The compression force sensor is configured to sense a compression force transmitted longitudinally through the first housing and the second housing during at least one of compressing tissue between the anvil and the deck surface or firing the surgical instrument. The tension force sensor is configured to sense a tension force transmitted longitudinally through the movable member during at least one of compressing tissue between the anvil and the deck surface or firing the surgical instrument.

Description

BACKGROUND

[0001] Examples of circular staplers are described in U.S. Patent No. 5,205,459, entitled “Surgical Anastomosis Stapling Instrument,” issued April 27, 1993; U.S. Patent No. 5,271,544, entitled “Surgical Anastomosis Stapling Instrument,” issued December 21, 1993; U.S. Patent No. 5,275,322, entitled “Surgical Anastomosis Stapling Instrument,” issued January 4, 1994; U.S. Patent No. 5,285,945, entitled “Surgical Anastomosis Stapling Instrument,” issued February 15, 1994; U.S. Patent No. 5,292,053, entitled “Surgical Anastomosis Stapling Instrument,” issued March 8, 1994; U.S. Patent No. 5,333,773, entitled “Surgical Anastomosis Stapling Instrument,” issued August 2, 1994; U.S. Patent No. 5,350,104, entitled “Surgical Anastomosis Stapling Instrument,” issued September 27, 1994; U.S. Patent No. 5,533,661, entitled “Surgical Anastomosis Stapling Instrument,” issued July 9, 1996; and U.S. Patent Publication No. 8,910,847, entitled “Low Cost Anvil Assembly for a Circular Stapler,” issued December 16, 2014. The disclosures of each of the above-cited U.S. Patents are incorporated by reference herein.

[0002] Some circular staplers can include a motorized actuation mechanism. Examples of circular staplers having motorized actuation mechanisms are described in U.S. Pub. No. 2015 / 0083772, entitled “Surgical Stapler with Rotary Cam Drive and Return,” published March 26, 2015 (now abandoned); U.S. Pat. No. 9,936,949, entitled “Surgical Stapling Instrument with Drive Assembly Having Toggle Features,” issued March 26, 2015; U.S. Pat. No. 9,907,552, entitled “Control Features for Motorized Surgical Stapling Instrument,” issued March 6, 2018; and U.S. Pat. No. 9,713,469, entitled “Surgical Stapler with Rotary Cam Drive,” issued July 25, 2017. The disclosure of each of the above-cited U.S. Pat. Pub. and U.S. Pat. is incorporated by reference herein.

[0003] While various surgical stapling instruments and associated components have been made and used, it is believed that no one prior to the inventors has made or used the application described in the appended claims. BRIEF DESCRIPTION OF DRAWINGS

[0004] Although the present specification describes particular features of the technology, it is not to be limited to those features. It is to be understood that in this application, relative terms are used to describe one feature in terms of or relative to another feature, which is then readily transferred to other features without additional language. Other examples and use cases for the technology will be recognized by those of ordinary skill in the art from the following description of certain examples described with reference to the following drawings, in which like numerals refer to like elements throughout the several views, and wherein:

[0005] FIG. 1 A perspective view of an exemplary circular surgical stapler is shown;

[0006] FIG. 2 A perspective view of the circular stapler of FIG. 1 , with the battery pack removed from the handle assembly and the anvil removed from the stapling head assembly;

[0007] FIG. 3 A perspective view of the anvil of the circular stapler of FIG. 1 ;

[0008] FIG. 4 A perspective view of the stapling head assembly of the circular stapler of FIG. 1 ;

[0009] FIG. 5 A perspective view of the stapling head assembly of the circular stapler of FIG. 4exploded perspective view of the stapling head assembly of

[0010] FIG. 6 illustrates FIG. 1 exploded perspective view of the circular stapler of

[0011] FIG. 7A illustrates FIG. 3 cross-sectional side view of the anvil positioned within a first segment of the digestive tract and FIG. 4 cross-sectional side view of the stapling head assembly positioned within a second segment of the digestive tract, wherein the anvil is separate from the stapling head assembly;

[0012] FIG. 7B illustrates FIG. 3 cross-sectional side view of the anvil positioned within a first segment of the digestive tract and FIG. 4 cross-sectional side view of the stapling head assembly positioned within a second segment of the digestive tract, wherein the anvil is secured to the stapling head assembly;

[0013] FIG. 7C illustrates FIG. 3 cross-sectional side view of the anvil positioned within a first segment of the digestive tract and FIG. 4 cross-sectional side view of the stapling head assembly positioned within a second segment of the digestive tract, wherein the anvil is retracted toward the stapling head assembly, thereby clamping tissue between the anvil and the stapling head assembly;

[0014] FIG. 7D illustrates FIG. 3 cross-sectional side view of the anvil positioned within a first segment of the digestive tract and FIG. 4 cross-sectional side view of the stapling head assembly positioned within a second segment of the digestive tract, wherein the stapling head assembly is actuated to sever and staple the clamped tissue;

[0015] FIG. 7E illustrates FIG. 7A cross-sectional side view of a first segment and a second segment of the digestive tract joined together at an end-to-end anastomosis of

[0016] FIG. 8 illustrates FIG. 1 cross-sectional view of another example circular surgical stapler similar to

[0017] FIG. 9 illustrates FIG. 8 cross-sectional view of the housing assembly of the circular surgical stapler of

[0018] FIG. 10 illustrates FIG. 8enlarged perspective view of the distal end of the circular stapler of FIG. 9 , with the compression force sensor disposed between the platform member and

[0019] FIG. 11 An enlarged detail portion of the cross-sectional view of FIG. 9 is shown, schematically illustrating the compression force sensor disposed between the outer shell and the outer shaft;

[0020] FIG. 12 An enlarged detail portion of the cross-sectional view of FIG. 9 is shown, schematically illustrating the compression force sensor disposed between the outer shaft and the outer shell of the handle assembly;

[0021] FIG. 13 An enlarged detail portion of the cross-sectional view of FIG. 9 is shown, schematically illustrating the compression force sensor disposed between the outer shell of the handle assembly and the knob;

[0022] FIG. 14 A perspective view of the movable member and anvil of FIG. 8 in combination with a control system, wherein the movable member includes at least one tension sensor;

[0023] FIG. 15 A perspective view of a user interface feature of the handle assembly of FIG. 8 ; and

[0024] FIG. 16 A diagrammatic view illustrating an exemplary method of operating FIG. 8 ; and

[0025] The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the technology can be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The drawings are intended to illustrate several aspects of the technology, and to provide a description of several embodiments of the technology; numerous other embodiments are contemplated, and are included in the scope of the technology. DETAILED DESCRIPTION

[0026] The following description of certain examples of the technology should not be used to limit the scope of the technology. Other examples, features, aspects, embodiments, and advantages of the technology will become apparent to those of ordinary skill in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the technology. As will be realized, the technology described herein is capable of other different and obvious aspects, all without departing from the technology. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.

[0027] For the sake of clarity in disclosure, the terms "proximal" and "distal" are defined herein relative to a surgeon or other operator holding a surgical instrument having a distal surgical end effector. The term "proximal" refers to a location of an element closer to the surgeon and the term "distal" refers to a location of an element closer to the surgical end effector of the surgical instrument and further from the surgeon. In addition, to the extent that spatial terms such as "top," "bottom," "up," "down," "vertical," "horizontal," and the like are used herein with reference to the drawings, it is understood that such terms are merely used for exemplary descriptive purposes and are not intended to be limiting or absolute. In this regard, it is to be understood that surgical instruments such as those disclosed herein can be used in a variety of orientations and positions other than those shown and described herein.

[0028] I. Overview of an Example Circular Surgical Stapling Instrument

[0029] FIGS. 1-2 An exemplary circular surgical stapling instrument (10) is shown that can be used to provide an end-to-end, side-to-side, or end-to-side anastomosis between two segments of an anatomical lumen, such as a portion of a patient's digestive tract. The instrument (10) of this example includes a body assembly, e.g., a handle assembly (100), a shaft assembly (200) extending distally from the handle assembly (100), a stapling head assembly (300) at a distal end of the shaft assembly (200), and an anvil (400) configured to releasably couple and cooperate with the stapling head assembly (300) to clamp, staple, and cut tissue. As will be described in greater detail below, the instrument (10) also includes a removable battery pack (120) operable to provide electrical power to a motor (160) housed within the handle assembly (100).

[0030] The shaft assembly (200) extends distally from the handle assembly (100) and includes a pre-formed curve. The stapling head assembly (300) is located at a distal end of the shaft assembly (200). As FIGS. 1-2As shown and as will be described in greater detail below, the anvil (400) is configured to be removably coupled adjacent the stapling head assembly (300) with the shaft assembly (200). Moreover, as will be described in greater detail below, the anvil (400) and the stapling head assembly (300) are configured to cooperate to manipulate tissue in three ways, including clamping tissue, cutting tissue, and stapling tissue. A knob (130) at a proximal end of the handle assembly (100) is rotatable relative to the housing (110) to provide precise clamping of tissue between the anvil (400) and the stapling head assembly (300). When a safety trigger (140) of the handle assembly (100) is pivoted away from a firing trigger (150) of the handle assembly (100), the firing trigger (150) can be actuated to provide cutting and stapling of tissue.

[0031] A. Example Anvil

[0032] As best shown in FIG. 3 The anvil (400) of the present example includes a head (420) and a shank (410). The head (410) includes a proximal surface (412) that defines a plurality of staple-forming pockets (414). In the present example, the staple-forming pockets (414) are arranged in two concentric annular arrays. The staple-forming pockets (414) are configured to deform a staple when the staple is driven into the staple-forming pockets (414). The proximal surface (412) terminates at an inner edge (416) that defines an outer boundary of an annular recess (418) that surrounds the shank (420).

[0033] The shank (420) defines a bore (422) and includes a pair of pivoting latch members (430). The latch members (430) are positioned within the bore (422) such that distal ends (434) are positioned at proximal ends of transverse openings (424) formed through sidewalls of the shank (420). The latch members (430) thus function as retaining clips. This allows the anvil (400) to be removably secured to an actuatable closure member in the form of a trocar (330) of the stapling head assembly (300), as will be described in greater detail below.

[0034] B. Example Stapling Head Assembly

[0035] As FIG. 4 and FIG. 5As best seen in FIGS. 1 and 2, the stapling head assembly (300) of the present example is coupled to the distal end of the shaft assembly (200) and includes a body member (310) and a staple driving member (350) slidably housed therein. The body member (310) includes a distally extending cylindrical inner core member (312). The body member (310) is fixedly secured to the outer sheath (210) of the shaft assembly (200), and thus the body member (310) and the outer sheath (210) together function as a mechanical ground for the stapling head assembly (300).

[0036] The trocar (330) is coaxially positioned within the inner core member (312) of the body member (310). As will be described in greater detail below, the trocar (330) is operable to translate distally and proximally relative to the body member (310) in response to rotation of the knob (130) relative to the housing (110) of the handle assembly (100). The trocar (330) includes a shaft (332) and a head (334). The head (334) includes a pointed tip (336) and an inwardly extending proximal surface (338). The head (334) and a distal portion of the shaft (332) are configured for insertion into the aperture (422) of the anvil (400). The proximal surface (338) and the latching shelf (436) have complementary locations and configurations such that the latching shelf (436) engages the proximal surface (338) when the handle (420) of the anvil (400) is fully seated on the trocar (330). Thus, the anvil (400) is secured to the trocar (330) by a snap engagement provided by the latching member (430).

[0037] The staple driving member (350) is operable to be longitudinally actuated within the body member (310) in response to activation of the motor (160), as will be described in greater detail below. The staple driving member (350) of the present example includes two distally presented concentric annular arrays of staple drivers (352). The staple drivers (352) are arranged to correspond to the arrangement of the staple forming pockets (414) of the anvil (400). Thus, each staple driver (352) is configured to drive a corresponding staple into a corresponding staple forming pocket (414) when the stapling head assembly (300) is actuated. The staple driving member (350) further defines a bore (354) configured to coaxially receive the core member (312) of the body member (310). An annular array of bolts (356) protrude distally from a distally presented surface surrounding the bore (354).

[0038] A cylindrical knife member (340) is positioned coaxially within the staple driving member (350). The knife member (340) includes a distally presented sharp circular cutting edge (342). The knife member (340) is dimensioned so that it defines an outer diameter that is less than the diameter defined by the inner annular array of the staple drivers (352). The knife member (340) also defines an opening configured to coaxially receive the core member (312) of the body member (310). An annular array of openings (346) formed in the knife member (340) are configured to complement the annular array of studs (356) of the staple driving member (350) so that the knife member (340) is securely fixed to the staple driving member (350) via the studs (356) and openings (346).

[0039] The platform member (320) is securely fixed to the distal end of the body member (310). The platform member (320) includes a distally presented platform surface (322) that defines two concentric annular arrays of staple openings (324). The staple openings (324) are arranged to correspond to the arrangement of staple drivers (352) and staple-forming pockets (414) described above. Thus, each staple opening (324) is configured to provide a path for a corresponding staple driver (352) to drive a corresponding staple through the platform member (320) and into a corresponding staple-forming pocket (414) when the stapling head assembly (300) is actuated. As FIG. 9 As best seen in FIG. 6, the platform member (320) defines an inner diameter that is only slightly larger than the outer diameter defined by the knife member (340). Thus, the platform member (320) is configured to allow the knife member (340) to be translated distally to a point where the cutting edge (342) is distanced from the platform surface (322).

[0040] C. Example Shaft Assembly

[0041] FIG. 6Various components of the shaft assembly (200) that couple components of the stapling head assembly (300) with components of the handle assembly (100) are shown. In particular, and as described above, the shaft assembly (200) includes an outer sheath (210) that extends between the handle assembly (100) and the main body member (310). The shaft assembly (200) also includes a trocar actuation rod (220) and a trocar actuation band assembly (230). A distal end of the trocar actuation band assembly (230) is fixedly secured to a proximal end of the trocar shaft (332). A proximal end of the trocar actuation band assembly (230) is fixedly secured to a distal end of the trocar actuation rod (220). It will thus be appreciated that the trocar (330) translates longitudinally relative to the outer sheath (210) in response to translation of the trocar actuation band assembly (230) and the trocar actuation rod (220) relative to the outer sheath (210). A clamp (222) is fixedly secured to the trocar actuation rod (220) and is configured to cooperate with a complementary feature within the handle assembly (100) to prevent rotation of the trocar actuation rod (220) within the handle assembly (100) while still allowing longitudinal translation of the trocar actuation rod (220) within the handle assembly (100). The trocar actuation rod (220) also includes a coarse helical thread (224) and a fine helical thread (226).

[0042] The shaft assembly (200) also includes a stapling head assembly driver (240) that is slidably received within the outer sheath (210). A distal end of the stapling head assembly driver (240) is fixed to a proximal end of the staple drive member (350). A proximal end of the stapling head assembly driver (240) is fixed to the drive carriage (250) via a pin (242). It will thus be appreciated that the staple drive member (350) translates longitudinally relative to the outer sheath (210) in response to translation of the stapling head assembly driver (240) and the drive carriage (250) relative to the outer sheath (210).

[0043] D. Example Handle Assembly and User Input Features

[0044] As FIG. 1As shown, the handle assembly (100) includes a housing (110) having a lower portion defining a pistol grip (112) in an inclined orientation and an upper portion supporting user interface features (114), as described in greater detail below. The handle assembly (100) also includes several features that are operable to actuate the anvil (400) and the stapling head assembly (300). Specifically, the handle assembly (100) includes a rotatable knob (130), a safety trigger (140), a firing trigger (150), a motor (160), and a motor activation module (180). The knob (130) is coupled with the trocar actuation rod (220) by a nut (not shown) such that the coarse helical threads (224) will selectively engage threaded engagement features inside the nut; and such that the fine helical threads (226) will selectively engage threaded engagement features inside the knob (130) interior. These complementary structures are configured such that the trocar actuation rod (220) will first translate proximally at a relatively slower rate, and then at a relatively faster rate, in response to rotation of the knob (130).

[0045] It should be appreciated that rotation of the knob (130) will provide corresponding translation of the anvil (400) relative to the stapling head assembly (300) when the anvil (400) is coupled with the trocar (330). It should also be appreciated that the knob (130) can be rotated in a first angular direction (e.g., clockwise) to retract the anvil (400) toward the stapling head assembly (300); and can be rotated in a second angular direction (e.g., counterclockwise) to advance the anvil (400) away from the stapling head assembly (300). Thus, the gap distance (d) between the opposing surfaces (412, 322) of the anvil (400) and the stapling head assembly (300) can be adjusted using the knob (130) until a suitable gap distance (d) is achieved, for example, as shown below. FIG. 7C

[0046] ​The firing trigger (150) is operable to activate the motor (160) to thereby actuate the stapling head assembly (300). The safety trigger (140) is operable to selectively hinder actuation of the firing trigger (150) based on the longitudinal position of the anvil (400) relative to the stapling head assembly (300). The handle assembly (100) further includes a component operable to selectively lock both triggers (140, 150) based on the position of the anvil (400) relative to the stapling head assembly (300). For example, the safety trigger (140) can be hindered from rotating from the engaged position to the disengaged position until the position of the anvil (400) relative to the stapling head assembly (300) is within a predefined range. Thus, actuation of the firing trigger (150) is hindered by the safety trigger (140) to thereby inhibit firing of the stapling head assembly (300) until the anvil position is within the predefined range.

[0047] When the firing trigger (150) is pivoted to the firing position, the firing trigger (150) is operable to actuate a switch of the motor activation module (180) FIG. 1 ). The motor activation module (180) is in communication with the battery pack (120) and the motor (160) such that the motor activation module (180) is configured to provide power from the battery pack (120) for activation of the motor (160) in response to the paddle actuating the switch of the motor activation module (180). Thus, the motor (160) will be activated upon pivoting of the firing trigger (150). This activation of the motor (160) will actuate the stapling head assembly (300) via the drive carriage (250), as described in greater detail below. As FIGS. 1-2 The handle assembly (100) is further configured to releasably receive the battery pack (120), which is operable to provide power to the motor (160), as described above, as best seen in

[0048] E. Example Stapling Procedures Utilizing Circular Stapling Instruments

[0049] FIGS. 7A-7E An instrument (10) for forming an anastomosis (70) between two tubular anatomical structures (20, 40) is shown. By way of example only, the tubular anatomical structures (20, 40) can comprise segments of a patient's esophagus, segments of a patient's colon, other segments of a patient's digestive tract, or any other tubular anatomical structures.

[0050] As shown in FIG. 7A , the anvil (400) is positioned in one tubular anatomical structure (20) and the stapling head assembly (300) is positioned in the other tubular anatomical structure (40). As shown in FIG. 7AAs shown, the anvil (400) is positioned in the tubular anatomical structure (20) such that the shank (420) protrudes from the open, severed end (22) of the tubular anatomical structure (20). In this example, the purse string suture (30) is disposed about the middle region of the shank (420) to generally secure the position of the anvil (400) in the tubular anatomical structure (20). The stapling head assembly (300) is positioned in the tubular anatomical structure (40) such that the trocar (330) protrudes from the open, severed end (42) of the tubular anatomical structure (20). The purse string suture (50) is disposed about the middle region of the shaft (332) to generally secure the position of the stapling head assembly (300) in the tubular anatomical structure (40). The stapling head assembly (300) is then pushed distally to ensure that the stapling head assembly (300) is fully seated at the distal end of the tubular anatomical structure (40).

[0051] Next, the anvil (400) is secured to the trocar (330) by inserting the trocar (330) into the hole (422), as shown. FIG. 7B The latching member (430) engages the head (334) of the trocar (330), thereby providing a secure fit between the anvil (400) and the trocar (330). The operator then rotates the knob (130) while holding the housing (110) stationary via the pistol grip (112). This rotation of the knob (130) causes the trocar (330) and the anvil (400) to retract proximally. As shown, FIG. 7C This proximal retraction of the trocar (330) and the anvil (400) compresses the tissue of the tubular anatomical structures (20, 40) between the surfaces (412, 322) of the anvil (400) and the stapling head assembly (300). As this occurs, the operator can observe a tactile resistance or feedback via the knob (130) as the knob (130) is turned, where such tactile resistance or feedback indicates that the tissue is being compressed. As the tissue is compressed, the operator can visually observe the position of the indicator pin (522) within the user interface feature (114) of the handle assembly (100) to determine whether the gap distance (d) between the opposing surfaces (412, 322) of the anvil (400) and the stapling head assembly (300) is appropriate; and make any necessary adjustments via the knob (130).

[0052] Once the operator has appropriately set the gap distance (d) via the knob (130), the operator pivots the safety trigger (140) toward the pistol grip (112) to activate actuation of the firing trigger (150). The operator then pivots the firing trigger (150) toward the pistol grip (112), thereby causing the paddle (158) to actuate the switch of the motor activation module (180) and thereby activate rotation of the motor (160). This rotation of the motor (160) causes actuation (or "firing") of the stapling head assembly (300) by actuating the drive carriage (250) distally, thereby driving the knife member (340) and the staple drive member (350) distally, as shown in FIG. 7D When the knife member (340) translates distally, the cutting edge (342) of the knife member (340) cuts excess tissue located within the annular recess (418) of the anvil (400) and the interior of the knife member (340).

[0053] As shown in FIG. 3 The anvil (400) of the present example includes a breakable washer (417) positioned within the annular recess (418). This washer (417) is broken by the knife member (340) as the knife member (340) completes a full range of distal movement from the position shown in FIG. 7C to the position shown in FIG. 7D In versions that include the washer (417), it should be appreciated that the washer (417) can also act as a cutting board for the knife member (340) to help cut tissue. As the staple drive member (350) translates distally from the position shown in FIG. 7C to the position shown in FIG. 7D The staple drive member (350) drives the staples (90) through tissue of the tubular anatomical structures (20, 40) and into the staple-forming pockets (414) of the anvil (400) as the staple drive member (350) translates distally from the position shown in

[0054] After the operator has actuated the stapling head assembly (300) as shown in FIG. 7D The operator then removes the instrument (10) from the patient, with the anvil (400) still secured to the trocar (330). With the instrument (10) removed, the tubular anatomical structures (20, 40) are secured together at the anastomosis (70) by the two annular arrays of staples (90), as shown in FIG. 7EThe inner diameter of the anastomosis portion (70) is defined by the severed edges (60) left by the knife member (340).

[0055] II. Example Circular Surgical Stapling Instruments with Force Sensing Assemblies

[0056] A. Overview

[0057] Applying an appropriate amount of tissue compression prior to firing (i.e., pre-fire tissue compression) and / or firing the instrument (10) with an appropriate amount of force can improve staple formation. As used herein, firing is the distal actuation of the staples and knife (e.g., knife member (340)) into clamped tissue, and pre-fire tissue compression is tissue compression that occurs prior to firing (i.e., the distal actuation of the staples and knife into clamped tissue). Pre-fire tissue compression of the instrument (10) is generally shown in FIG. 7C , and firing of the instrument (10) is generally shown in FIG. 7D . Applying an appropriate amount of force can be beneficial for both manual circular staplers and powered circular staplers. Moreover, it can be desirable to monitor such forces experienced by and transmitted through the instrument (10) to assess their impact on the performance and life of the instrument (10). Thus, it would be beneficial to determine pre-fire tissue compression forces and / or forces to fire the instrument (10) using actual data from the instrument (10) because tissue thickness can vary from patient to patient, which can change the desired amount of compression force.

[0058] It can also be desirable to provide some form of circular surgical stapling instrument (10) that determines pre-fire tissue compression forces and / or forces to fire the instrument (10) and communicates that information to the user and / or combines that information with other information from other stapling procedures. Obtaining real-time data can allow the user to take action to improve staple formation. Moreover, evaluating data from multiple instruments can allow for the identification of trends and implementation of changes. This can allow the instrument (10) to provide more consistent pre-fire tissue compression forces and / or firing forces. Thus, measuring and tracking pre-fire tissue compression forces and / or firing forces of the instrument (10) can be beneficial to the user during the procedure and to the user after the procedure.

[0059] Additionally, it can be desirable to provide a version of the instrument (10) that determines the pre-firing tissue compression force and firing force without directly measuring that data at the distal end of the instrument (10). Indirect measurement of the actual pre-firing tissue compression force and / or firing force can eliminate the need to route one or more wires through at least portions of the shaft assembly (200) and stapling head assembly (300) to connect the sensors with the control system. For example, it can be difficult to route one or more wires between the deck surface (322) of the deck member (320) and the proximal surface (412) of the anvil (400). Accordingly, additionally, it can be desirable to place one or more sensors outside of the distal end of the instrument (10) to indirectly determine the pre-firing tissue compression force and / or firing force using analysis of the actual tension and compression forces experienced by the instrument (10).

[0060] The following description provides several examples of variations of the instrument (10) that provide the various force sensing features and capabilities described above.

[0061] B. Example Circular Surgical Stapling Instruments

[0062] FIGS. 8-15 Another example circular surgical stapling instrument (500) exhibiting the above-described kinds of configurations and functionality is shown. It will be appreciated that the instrument (500) is similar to the instrument (10) described above unless otherwise noted below. In particular, FIG. 8 A cross-sectional view of the instrument (500) is shown similar to the instrument (10) of FIG. 1 but wherein the instrument (500) additionally includes a force sensing assembly (502).

[0063] Similar to the instrument (10), the instrument (500) includes a body assembly in the form of a handle assembly (508) (similar to the handle assembly (100)), a shaft assembly (510) (similar to the shaft assembly (200)), a stapling head assembly (512) (similar to the stapling head assembly (300)), an anvil (514) (similar to the anvil (400)), and an actuator in the form of a rotatable knob (516) (similar to the knob (130)). It is contemplated that the actuator can include other suitable alternatives (including a manually slidable lever), or can be powered using the motor (160) or another similar motor. These components are similar to the corresponding components of the instrument (10) described above with reference to FIGS. 1-8. FIGS. 1-7E Similar to the instrument (10), the handle assembly (508) is configured to be grasped by a user, the shaft assembly (510) extends distally from the handle assembly (508), and the stapling head assembly (512) is disposed at a distal end of the shaft assembly (510).

[0064] As will be described in greater detail below, the force sensing assembly (502) includes at least one compression force sensor (504) configured to sense a compression force experienced by the instrument (500) and / or at least one tension force sensor (506) configured to sense a tension force experienced by the instrument (500). For example, the force sensing assembly (502) can include at least one compression force sensor (504), at least one tension force sensor (506), or at least one compression force sensor (504) and at least one tension force sensor (506). The instrument (500) can be considered a compression and tension system during tissue compression (i.e., clamping) and during firing of the instrument (500). When the anvil (514) clamps the compressed tissue, components in the instrument (500) experience at least one of tension or compression. During firing, the magnitude of these tension and compression forces in the instrument (500) increase.

[0065] As will be described in greater detail below, the force sensing assembly (502) includes at least one compression force sensor (504) configured to sense a compression force experienced by the instrument (500) and / or at least one tension force sensor (506) configured to sense a tension force experienced by the instrument (500). For example, the force sensing assembly (502) can include at least one compression force sensor (504), at least one tension force sensor (506), or at least one compression force sensor (504) and at least one tension force sensor (506). The instrument (500) can be considered a compression and tension system during tissue compression (i.e., clamping) and during firing of the instrument (500). When the anvil (514) clamps the compressed tissue, components in the instrument (500) experience at least one of tension or compression. During firing, the magnitude of these tension and compression forces in the instrument (500) increase. FIGS. 8-15 In greater detail, the instrument (500) includes a housing assembly (518) and a movable member (520), where the movable member (520) moves relative to the housing assembly (518) using an actuator (e.g., a knob (516)). When the anvil (514) is coupled with a trocar (522) (similar to the trocar (330)) and the knob (130) is rotated by a user, the housing assembly (518) experiences a compression force and the movable member (520) experiences a tension force. The tensioning caused by the rotational input on the knob (516) results in the movable member (520), including the trocar (522), moving proximally. In other words, applying torque to close the gap (d) using the rotatable knob (516) pulls the movable member (520) proximally, creating compression and tension forces. Thus, stresses and / or strains can be measured in the instrument (500). As FIG. 10 As shown, the housing assembly (518) is collectively defined by the handle assembly (508), which experiences compression forces, the shaft assembly (510), the stapling head assembly (512), and the adjacent housing of the knob (516). As FIG. 14 As shown, the movable member (520) is collectively formed by the shaft assembly (510) of the stapling head assembly (512) and portions of the trocar (522).

[0066] C. Example Control Systems

[0067] The instrument (500) can include a control system (524) operable to control actuation of the instrument (500). The control system (524) can include user interface features (526), a motor unit, and associated circuitry that interfaces with the force sensing assembly (502). The compression force sensor (504) and the tension force sensor (506) can be electrically coupled with the control system (524) using one or more wires (528). As referenced above, the control system (524) can be configured to determine a force experienced by the instrument (500) based on the output of the compression force sensor (504) and / or the tension force sensor (506). FIG. 15In further detail, the user interface feature (526) can indicate whether the sensed compression force and / or the sensed tension is within an acceptable range. The control system (524) can include a processor, a memory, and a printed circuit board. The control system (524) can be disposed within the instrument (500) or external to the instrument (500) but in wired or wireless communication with the instrument (500). The control system (524) can be operable to store preprogrammed instrument control algorithms and receive input from the user interface feature (526) and the force sensing assembly (502). Based on these stored control algorithms and received input, the control system (524) is configured to determine tissue compression at the distal end of the instrument (500).

[0068] This tissue compression data can be processed on an integrated printed circuit board (PCB) of the instrument (500) and uploaded to cloud storage for subsequent data analysis. For example, average firing forces can be determined as well as other characteristics. Although not shown, a printed circuit board (PCB) can be disposed in the handle assembly (508) near the user interface feature (526). For example, wires (528) can be routed to the PCB for electrical resistance interpretation and correlation to compression forces. In some versions, at least one of the control system (524) or the user interface feature (526) can be in signal communication with an external network such that compression force data can be directly uploaded to the cloud for data interpretation. For example, the teachings disclosed herein can be combined with any of the teachings of the following U.S. publications and patent applications: U.S. Publication 2019 / 0201136, entitled “Method of Hub Communication,” published July 4, 2019; U.S. Publication 2019 / 0206569, entitled “Method of Cloud Based Data Analytics for Use with the Hub,” published July 4, 2019; U.S. Publication 2020 / 0100830, entitled “Method for Constructing and Using a Modular Energy System with Multiple Devices,” published April 2, 2020; and Patent Application 63 / 018,664, entitled “Stabilizer for Surgical Shafts or Cannulas,” filed May 1, 2020, the disclosures of which are incorporated by reference herein. In some versions, tissue compression data can be pushed to a desired smart connected device.

[0069] D. Example Anvils

[0070] Anvil (514) is similar to the anvil (400) described above with reference to FIG. 3 The anvil (514) is configured to selectively couple with the movable member (520) to clamp, staple, and cut tissue using the stapling head assembly (512). The anvil (514) and the stapling head assembly (512) are configured to cooperate in three ways to manipulate tissue, including clamping tissue, cutting tissue, and stapling tissue. The anvil (514) of the present example includes a head (530) and a shank (532). The head (530) includes a proximal surface (534) that defines a plurality of staple-forming pockets (not shown) similar to the staple-forming pockets (414). The staple-forming pockets are configured to deform staples when the staples are driven into the staple-forming pockets.

[0071] In particular, the anvil (514) selectively couples with the trocar (522) using a latch member (536) similar to the latch member (430). The latch member (536) functions as a retaining clip to allow the anvil (514) to be removably secured to the actuable closure member in the form of the trocar (522). The anvil (514) is selectively retractable and extendable by the trocar (522) relative to the stapling head assembly (512) to clamp tissue against a distally-facing deck surface (538) of a deck member (540) similar to the deck member (320). Rotation of the knob (516) provides corresponding translation of the anvil (514) relative to the stapling head assembly (512) when the anvil (514) is coupled with the trocar (522).

[0072] E. Example Compression Force Sensing

[0073] FIG. 9 It is shown that FIG. 8FIG. 1 illustrates a perspective view of a surgical instrument (500) in accordance with at least one embodiment. As shown, the surgical instrument (500) includes a handle assembly (508), a housing assembly (518), a platform member (540), and a body member (546). The handle assembly (508) includes a housing (542) and an actuator (e.g., a knob (516)). The housing (542) can include a first housing and a second housing. The first housing and the second housing can be positioned adjacent to one another. In some versions, the first housing and the second housing are prevented from translating relative to one another. For example, in some versions, the first housing and the second housing are fixedly coupled together using a variety of suitable methods. The housing assembly (518) includes at least one compression force sensor (504) positioned between the first housing and the second housing of the housing assembly (518). For example, the first housing and the second housing can include the actuator (e.g., the knob (516)), the housing (542) of the handle assembly (508), the platform member (540) (i.e., a guide), an outer sheath (544) (similar to the outer sheath (210)), and the body member (546) (similar to the body member (310)). The compression force sensor (504) is configured to sense a compression force transmitted longitudinally through the housing assembly (518) when tissue is compressed between the compression anvil (514) and the platform surface (538) of the platform member (540) (i.e., pre-firing tissue compression force) and / or through a firing of the surgical instrument (500) (i.e., firing force). As used herein, the pre-firing tissue compression force is the force experienced by the surgical instrument (500) as tissue is brought into position in preparation for firing, while the firing force is the force experienced by the surgical instrument (500) through a firing sequence (e.g., cutting and stapling of tissue). The compression force sensor (504) can include a pressure sensor. For example, the pressure sensor can include a load cell. The compression force can be experienced between adjacent components of the housing assembly (518) (i.e., the first housing and the second housing). The compression force sensor (504) can be electrically coupled with a control system (524) using one or more wires (528).

[0074] FIG. 10 FIG. 2 illustrates a perspective view of a distal end of the surgical instrument (500) of FIG. 1, wherein the compression force sensor (504) is positioned between the platform member (540) and the body member (546) of the surgical instrument (500). FIG. 8 FIG. 3 illustrates a perspective view of a distal end of the surgical instrument (500) of FIG. 1, wherein the compression force sensor (504) is positioned between the platform member (540) and the body member (546) of the surgical instrument (500). FIG. 9 FIG. 4 illustrates a perspective view of a distal end of the surgical instrument (500) of FIG. 1, wherein the compression force sensor (504) is positioned between the platform member (540) and the body member (546) of the surgical instrument (500). FIG. 10The ring (548) is shown as an annular ring, but it is conceivable that the compression sensor (504) can take various suitable forms and may be non-annular. The compression sensor (504) senses the pre-firing tissue compression between the body member (546) and the platform member (540). The annular ring (548) allows for the measurement of pre-firing tissue compression between the platform member (540) and the body member (546). As shown, the platform member (540) is movable relative to the body member (546), which differs from that described in the reference device (10). The loose fit of the annular ring (548) allows the platform member (540) to selectively translate proximally and selectively apply pressure between the bottom surface (550) of the flange (552) of the platform member (540) and the distal end (554) of the body member (546). The platform component (540) is pushed toward the main component (546) to calculate the force on the compressed tissue prior to firing. As shown, an embedded electrical connector (shown as a wire (528)) may be disposed within the main component (546) to electrically connect the annular ring (548) to the control system (524). FIG. 8 (As shown in the figure). The platform component (540) includes a concentric ring array of pin openings (556) (similar to pin openings 324). In some other forms, the pin openings (556) may be arranged in three or more concentric ring arrays.

[0075] FIGS. 11-13 A representative location of the compression force sensor (504) is shown, positioned between the first and second housings of the housing assembly (518). Although FIGS. 11-13 A representative location of the pressure sensor (504) is shown, but other suitable locations and placements of the pressure sensor (504) are also conceivable. The first and second housings may be joined together at connection points subjected to compressive forces during tissue compression prior to firing and during firing of the instrument (500). Therefore, it may be advantageous to include one or more pressure sensors (504) disposed at these connection points. For example, the pressure sensor (504) may be disposed between the main body member (546) and the outer sheath (544). FIGS. 11-13 In each of the diagrams, the compression sensor (504) may include a load sensor.

[0076] FIG. 11 It shows FIG. 9The detailed portion includes a compression sensor (504) disposed between the proximal end (558) of the outer sheath (544) and the distal end (560) of the main body member (546). The compression sensor (504) can be electrically connected to the control system (524) using one or more wires (528). The compression sensor (504) can sense the pre-firing tissue compression force between the outer sheath (544) and the main body member (546). The main body member (546) is configured to surround at least a portion of the movable member (520). The main body member (546) includes a cylindrical inner core member (562) extending distally (similar to the inner core member (312)). The main body member (546) is securely attached to the outer sheath (544) of the shaft assembly (510). The main body member (546) and the outer sheath (544) together serve as a mechanical grounding element for the suture head assembly (512). The outer sheath (544) is configured to surround at least a portion of the movable member (520). The outer sheath (544) is fixed relative to the body member (546). The outer sheath (544) extends between the handle assembly (508) and the body member (546). In this example, the outer sheath (544) is rigid and includes a pre-formed curved segment (564) (in FIGS. 8-9 (as shown in the figure). The device (500) also includes a collar (566) surrounding at least a portion of the outer sheath (544), for example, as disclosed in U.S. Patent Application 16 / 887,182, filed May 29, 2020, entitled “Shaft Attachment Feature for Circular Surgical Stapler,” the disclosure of which is incorporated herein by reference.

[0077] FIG. 12 It shows FIG. 9 The detailed portion shows a compression sensor (504) disposed between the proximal end (568) of the outer sheath (544) and the internal mating feature (570) of the housing (542) of the handle assembly (508). The compression sensor (504) senses the pre-firing tissue compression force between the proximal end (568) of the outer sheath (544) and the internal mating feature (570) of the housing (542). The handle assembly (508) includes the housing (542). FIG. 9As shown, the housing (542) includes a proximal end and a distal end (572, 574). The housing (542) also includes a pistol grip (576) in an inclined orientation, with the user interface features (526) disposed on an upper portion (578) of the housing (542) adjacent the distal end (574) of the housing (542). The knob (516) is rotatably disposed at the proximal end (572) of the housing (542). The handle assembly (508) includes several features operable to actuate the anvil (514) and the stapling head assembly (512). Similar to the handle assembly (100), the handle assembly (508) also includes a safety trigger (582), a firing trigger (584), a motor (586), and a motor activation module (not shown). The handle assembly (508) also includes a removable battery pack (588) operable to provide power to the motor (similar to (160)) housed within the handle assembly (508). The firing trigger (150) is configured to activate the motor (160) to actuate the stapling head assembly (512). The safety trigger (140) is configured to selectively hinder actuation of the firing trigger (150) based on the longitudinal position of the anvil (514) relative to the stapling head assembly (512). As FIG. 9 As shown, the housing (542) of the present example includes an open proximal cavity (580) configured to releasably receive and retain the battery pack (588) and operable to power the motor (586) housed within the housing (542).

[0078] FIG. 13 As shown, FIG. 9FIG. 5 shows a detailed portion of the handle assembly (508) showing the pressure sensor (504) disposed between the housing (542) of the handle assembly (508) and the knob (516). Specifically, the pressure sensor (504) is disposed between the proximal end (572) of the housing (542) and the distal end (590) of the knob (516). The compression force sensor (504) can sense the pre-firing tissue compression force between the actuator (e.g., knob (516)) and the housing (542) of the handle assembly (508) and / or the firing force between the actuator (e.g., knob (516)) and the housing (542) of the handle assembly (508). The compression force sensor (504) can sense the compression force during the pre-firing tissue compression and during the firing sequence. The compression force sensor (504) can be electrically coupled with the control system (524) using one or more wires (528). As described above, the knob (516) is configured to translate the movable member (520) including the trocar (522) proximally and distally. The knob (516) can be rotated in a first angular direction (e.g., clockwise) to retract the anvil (514) toward the stapling head assembly (512); and can be rotated in a second angular direction (e.g., counterclockwise) to advance the anvil (514) away from the stapling head assembly (512). The gap distance (d) between the proximal surface (534) of the anvil (514) and the deck surface (538) of the deck member (540) can be adjusted using the knob (516) until a suitable gap distance (d) is achieved, as described above. FIG. 7C The tensioning caused by the rotational input on the knob (516) results in the trocar (522) moving proximally. The knob (516) is able to rotate relative to the housing (542) to provide precise clamping of tissue between the anvil (514) and the deck member (540).

[0079] F. Tension Sensing

[0080] FIG. 14 is shown FIG. 8FIG. 6 is a perspective view of a movable member (520) of the instrument (500). The movable member (520) is configured to actuate between at least an open position for receiving at least a first tissue layer and a second tissue layer and a closed position in which the at least first tissue layer and the second tissue layer are compressed together. The movable member (520) can be at least partially disposed within the housing assembly (518). As previously described, the movable member (520) is co-formed by the shaft assembly (510) and portions of the trocar (522) of the stapling head assembly (512). As shown, the movable member (520) includes the trocar (522), a trocar actuation rod (592), and a trocar actuation link assembly, shown as a trocar actuation band assembly (594). At least one tension sensor (506) can be coupled with the trocar actuation rod (592), the trocar actuation band assembly (594), and / or the trocar (522) to sense tension in the trocar actuation rod (592), the trocar actuation band assembly (594), and / or the trocar (522). The tension sensor (506) is configured to sense tension longitudinally transmitted through the movable member (520) and / or the trocar (522) as tissue is compressed between the compression anvil (514) and the deck surface (538) and / or the firing instrument (500). The tension sensor (506) can sense tension during pre-firing tissue compression and during a firing sequence.

[0081] The trocar actuation rod (592) has a proximal end and a distal end (596, 598) such that a proximal end (600) of the trocar actuation band assembly (594) is fixed relative to the distal end (598) of the trocar actuation rod (592). The proximal end 596 of the trocar actuation rod (592) is coupled with the knob (516). The trocar actuation rod (592) includes a coarse helical thread (602) and a fine helical thread (604). The knob (516) is coupled with the trocar actuation rod (592) via a nut (not shown) such that the coarse helical thread (602) selectively engages a thread engagement feature within an interior of the nut and the fine helical thread (226) selectively engages a thread engagement feature within an interior of the knob (516). As shown, the tension sensor (506) can be coupled with the trocar actuation rod (592) such that the tension sensor (506) can be electrically coupled with the control system (524) using one or more wires (528).

[0082] The tension sensor (506) can be coupled with the trocar actuation band assembly (594). The trocar actuation band assembly (594) can include a plurality of tension bands, shown as stacked together. As FIG. 14As shown, the trocar actuation band assembly (594) includes an upper tension band and a lower tension band (606, 608). In some versions, the upper and lower tension bands (606, 608) can be formed of a metallic material such that one of the upper and lower tension bands (606, 608) in the instrument (500) that retracts the anvil (514) against tissue under tension during tissue compression and firing, where the knife pushes the anvil (514). The tension sensor (506) can be fixedly couplable with one of the upper and lower tension bands (606, 608).

[0083] As shown, the tension sensor (506) is fixedly couplable with an upper surface (610) of the upper tension band (606). The tension sensor (506) can include a strain gauge (612). For example, the strain gauge (612) can be positioned on a planar portion (614) of the upper tension band (606) of the trocar actuation band assembly (594) that experiences tension during tissue compression. As the instrument (500) is fired, the upper tension band (606) experiences higher tension, which increase in strain can be sensed by the strain gauge (612) and transmitted to the control system (524) using one or more wires (528). As a result of the sensed strain, the control system (524) can then correlate the strain to the pre-firing tissue compression force and / or firing force at the distal end of the instrument (500). The tension sensor (506) can be embedded on the upper surface (610) and measure surface strain and back calculate the pre-firing tissue compression force and / or firing force at the distal end of the instrument (500). Alternatively, the strain gauge (612) can include an embedded strain gauge. The embedded strain gauge can be placed between respective components of the movable member (520). For example, the embedded strain gauge can be placed where two components mate. In some versions, a portion of the movable member (520) (e.g., a portion of the trocar actuation band assembly (594) or a portion of the trocar actuation rod (592)) can be removed and replaced with the embedded strain gauge. The trocar (522) is described below with reference to the embedded strain gauge (616).

[0084] As FIG. 14As shown, the pre-firing tissue compression force and / or firing force can be measured using a tension sensor (506) disposed in coupling with the trocar (522) such that the tension sensor (506) can be electrically coupled with the control system (524) using one or more wires (528). The trocar (522) is operable to translate distally and proximally relative to the body member (546) in response to rotation of the knob (516) relative to the housing (542) of the handle assembly (508). The trocar (522) includes a shaft (618) and a head (620). The head (620) includes a pointed tip (622) and an inwardly extending proximal surface (624). The head (620) and a distal portion of the shaft (618) are configured for insertion into a hole (not shown, but similar to the hole (422) of the anvil (400)). Thus, the anvil (514) is secured to the trocar (522) by a snap engagement provided by the latching member (536). The latching member (536) of the anvil (514) captures the trocar (522), causing a tension on the intermediate components of the movable member (520) (e.g., the trocar actuation rod (592), the trocar actuation band assembly (594)). The pre-firing tissue compression force and / or firing force can be measured using a strain gauge (626) on the shaft (618) of the anvil (514).

[0085] As FIG. 14 shown, the distal end (628) of the trocar actuation band assembly (594) is fixedly secured to the proximal end (630) of the shaft (618) of the trocar (522). It will thus be appreciated that the trocar (522) translates longitudinally relative to the outer sheath (544) in response to translation of the trocar actuation band assembly (594) and the trocar actuation rod (592) relative to the outer sheath (544). The trocar actuation band assembly (594) is configured to bend such that the trocar actuation band assembly (594) can progress in a pre-formed curve in the shaft assembly (510) as the trocar actuation band assembly (594) translates longitudinally relative to the outer sheath (544). However, the trocar actuation band assembly (594) has sufficient column strength and tensile strength to transmit distal and proximal forces from the trocar actuation rod (592) to the shaft (618) of the trocar (522). The trocar actuation rod (592) is rigid. The clamp (632) is fixedly secured to the trocar actuation rod (592) and is configured to cooperate with a complementary feature within the handle assembly (508) to prevent rotation of the trocar actuation rod (592) within the handle assembly (508) while still allowing longitudinal translation of the trocar actuation rod (592) within the handle assembly (508).

[0086] Similar to the stapling head assembly (300), the stapling head assembly (512) includes a deck member (540) and a trocar (522). The stapling head assembly (512) is selectively operable to eject staples distally into clamped tissue and against the anvil (514) and to cut the clamped tissue with a cylindrical knife member (not shown) similar to the knife member (340) described above. Thus, the stapling head assembly (512) and the anvil (514) cooperate to define an end effector stapling assembly that is operable to clamp, staple, and cut tissue in response to user input.

[0087] The instrument (500) can also be constructed and operated in accordance with at least some of the teachings of U.S. Patents and U.S. Publications entitled: “Circular Stapler with Selectable Motorized and Manual Control,” U.S. Patent 9,445,816, issued September 20, 2016; “Circular Stapler with Select Motorized and Manual Control, Including a Control Ring,” U.S. Patent 9,532,783, issued January 3, 2017; “Motor Driven Rotary Input Circular Stapler with Modular End Effector,” U.S. Patent 9,597,081, issued March 21, 2017; “Motor Driven Rotary Input Circular Stapler with Lockable Flexible Shaft,” U.S. Patent 9,463,022, issued October 11, 2016; “Surgical Stapler with Independently Actuated Drivers to Provide Varying Staple Heights,” U.S. Patent Publication 2018 / 0368836, published December 27, 2018; and / or any other patent reference identified herein, the disclosures of which are incorporated by reference herein.

[0088] G. Example Manually Actuated Circular Stapler

[0089] Although not shown, the force sensing assembly (502) can be incorporated into a manually actuated circular stapler rather than the instrument (500) shown as an electrically powered circular stapler. For example, the force sensing assembly (502) can be applied to a manually actuated circular stapler such as the kind described in U.S. Patent Publication 2020 / 0113565, entitled “Latch to Prevent Back-Driving of Circular Surgical Stapler,” published April 16, 2020, the disclosure of which is incorporated by reference herein. A power source (not shown) can be included to power the force sensing assembly (502) of the manually actuated circular stapler. For example, the power source can be electrically coupled with the strain gauges.

[0090] H. Example User Interface Features of Handle Assemblies

[0091] FIG. 15 A perspective view of a user interface feature (526) of a handle assembly (508) of the instrument (500) is shown. FIG. 8 The user interface feature (114) is configured to provide visual feedback to the operator indicating the positioning of the anvil (514) relative to the stapling head assembly (512) during a surgical procedure. The operator can observe the user interface feature (526) while rotating the knob (516) to confirm whether a suitable gap distance (d) has been achieved between the anvil (514) and the stapling assembly (512). The user interface feature (526) of the present example includes a graphical indicator (633) comprising fixed linear indicia (634, 636, 638), graphical representations of staples (640, 642), and a checkmark graphic (644). The user interface feature (114) also defines a window (646) through which an indicator pin (648) can be observed. The circular surgical stapling instrument (500) can also be constructed and operated in accordance with at least some of the teachings of U.S. Patent 10,709,452, issued July 14, 2020, which is incorporated by reference above.

[0092] The user interface feature (526) is configured to receive and communicate user inputs to the control system (524). In this regard, the user interface feature (526) can include one or more buttons, dials, other actuatable elements, or display graphics that can be selected by a user to indicate certain information related to a surgical procedure to be performed or related to the stapling head assembly (512). By way of example only, such information can include any of the following: a desired staple formation height; a corresponding gap between the anvil (514) and the stapling head assembly (512) at which the anvil (514) should be actuated during closure; a type or nominal thickness of tissue being fired by the instrument (500); and / or a diameter of the stapling head assembly (512). As the operator rotates the knob (516) to adjust the longitudinal position of the anvil (514) relative to the stapling head assembly (512), the operator can observe that the instrument (500) is actively sensing tissue compression forces.

[0093] This information can be provided to the surgeon on a real-time display (variables or attributes) to ensure that tissue compression is uniform. In some versions, the user interface feature (526) can display the compression force to the user. For example, the user interface feature (526) can include a tissue compression screen (650). An LED panel can be used to inform the user of the pre-fire tissue compression force. The pre-fire compression force can be presented as a discrete pass / fail signal (e.g., a colored indicator such as a green light and a red light) or a quantitative readout. For example, the strain data can be processed to determine the pre-fire tissue compression force and / or the firing force during the firing stroke at the distal end of the instrument (500). Alternatively, or in addition to the user interface feature (526), the instrument (500) can signal communicate with an external network so that the pre-fire tissue compression force and / or the firing force can be uploaded directly to the cloud for data interpretation to determine the relevant pre-fire tissue compression force and / or the firing force during the firing stroke at the distal end of the instrument (500). Additionally, the pre-fire tissue compression force and / or the firing force data can be recorded for real-time on-site monitoring and prevention of trends. The compression force can be obtained from the strain gauge and a correlation can be formulated to determine tissue compression and firing force tension values that correspond to the pre-fire tissue compression and / or the firing force at the distal end of the instrument (500).

[0094] I. Example Methods

[0095] Reference is made below to FIG. 16An exemplary method (700) of measuring tissue compression of a stapling instrument (500) is described. At step (702), the method (700) can comprise compressing tissue between an anvil (514) and a deck surface (538). At step (704), the method (700) can comprise firing the instrument (500) to drive staples through the tissue. At step (706), the method (700) can comprise measuring at least one of a compression force transmitted longitudinally through a housing assembly (518) between a first housing and a second housing and / or a tension force transmitted longitudinally through a movable member (520) or an anvil (514). As described above, a compression force sensor (504) disposed between the first housing and the second housing can be used to measure the compression force transmitted longitudinally through the housing assembly (518) when compressing tissue between the anvil (514) and the deck surface (538) or when firing the instrument (500).

[0096] For example, at least one compression force sensor (504) positioned at one or more of the following locations can be used to measure pre-firing tissue compression forces: a location between a deck member (540) and a body member (546) (i.e., an outer housing); a location between the body member and an outer sheath (544); a location between the outer sheath (544) and an outer housing (542) of a handle assembly (508); and a location between the outer housing (542) of the handle assembly (508) and a knob (516). At least one compression force sensor (504) positioned between the outer housing (542) of the handle assembly (508) and the knob (516) can be used to measure firing forces. As described above, a tension force sensor (506) coupled with the movable member (520) can be used to measure the tension force transmitted longitudinally through the movable member (520) when compressing tissue between the anvil (514) and the deck surface (538) or firing the instrument (500). For example, at least one tension force sensor (506) can be coupled with a trocar actuation rod (592), a trocar actuation band assembly (594), and / or a trocar (522) to sense tension in the trocar actuation rod (592), the trocar actuation band assembly (594), and / or the trocar (522).

[0097] At step (708), the method (700) can comprise determining at least one force based on the sensed compression force obtained from the compression force sensor (504) and / or the sensed tension force obtained from the tension force sensor (506). For example, a force at which the instrument (500) compresses tissue disposed between the platform surface (538) and the anvil (514) prior to firing of the instrument (500) and / or a force at which the firing assembly of the instrument (500) is actuated to fire the instrument (500) on the compressed tissue can be determined. Determining the tissue compression force can comprise using an algorithm to correlate measurements of compression force and / or tension force to an amount of tissue compression prior to firing of the instrument (500) or during firing of the instrument (500). The algorithm can be determined based on data from other firings that are sensed. The algorithm can comprise a transfer function that utilizes a calibration system to measure actual compression forces and then correlates corresponding strain and compression from various locations inside the instrument (500). For example, a lookup table can be used.

[0098] After determining the tissue compression force at step (710), the method (700) can comprise communicating the sensed force to the user interface feature (526) and / or communicating the sensed force to the control system (524). Communicating the sensed force can comprise producing an indication that the tissue compression is within an acceptable range. For example, the indication can comprise one or more of an audible, tactile, or visual indication. The instrument (500) can provide feedback to the user or an algorithm to ensure optimal compression. The instrument (500) can also collect data for post-processing related to performance of the instrument (500). For example, the instrument (500) can record data related to tissue compression prior to firing and tissue compression during firing. After determining the tissue compression, the method can also comprise uploading the tissue compression data to the cloud as described above.

[0099] The instrument (500) can provide a variety of benefits, including measuring and determining pre-fire tissue compression force and / or firing force of the instrument (10) using actual data from the instrument (10). In some versions, the instrument (500) can obtain real-time data, allowing the user to take action to improve staple formation and obtain data from multiple instruments to confirm trends of desired changes. In some versions, the instrument (500) can allow actual pre-fire tissue compression force and / or firing force to be measured using an algorithm without the need to route one or more wires through at least portions of the shaft assembly (510) and the stapling head assembly (512).

[0100] III. Example Combinations

[0101] The following embodiments relate to various non-exhaustive ways in which the teachings herein can be combined or applied. The following embodiments are not intended to limit the scope of any claims that can be presented by applicants of this patent application or in subsequent filings of this patent application, including attempts to pursue continuation, continuation-in-part, divisional, or related cases. No disclaimer is intended. The following embodiments are to be considered only as examples. Various teachings herein can be applied in a multitude of diverse ways. It is also contemplated that some variations can omit, substitute, or add to certain procedures or components. Thus, although a few embodiments have been described in detail, other modifications are possible and the general principles defined herein can be applied to other embodiments. To the extent that they can not be fully consistent with the above teachings, they are intended to be captured by the scope of the disclosure, which is defined by the claims.

[0102] EMBODIMENT 1

[0103] A surgical instrument comprising: (a) a housing assembly comprising: (i) a first housing; (ii) a second housing disposed adjacent the first housing; and (iii) a deck surface comprising at least one annular array of staple openings; (b) a movable member at least partially disposed within the housing assembly; (c) an anvil configured to selectively couple with the movable member to compress tissue between the anvil and the deck surface; and (d) a force sensing assembly, wherein the force sensing assembly comprises at least one of: (i) a compression force sensor disposed between the first housing and the second housing, wherein the compression force sensor is configured to sense a compression force transmitted longitudinally through the first housing and the second housing during at least one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument, or (ii) a tension force sensor coupled with the movable member or the anvil, wherein the tension force sensor is configured to sense a tension force transmitted longitudinally through the movable member during at least one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument.

[0104] EMBODIMENT 2

[0105] The surgical instrument of any of the preceding embodiments, wherein the force sensing assembly comprises the compression force sensor disposed between the first housing and the second housing.

[0106] EMBODIMENT 3

[0107] The surgical instrument of any of the preceding embodiments, wherein the compression force sensor comprises a load cell.

[0108] EMBODIMENT 4

[0109] The surgical instrument of any of the preceding embodiments, wherein the first housing comprises a body member configured to surround at least a portion of the movable member, wherein the second housing comprises a platform member, wherein the platform member comprises the platform surface, wherein the compression force sensor is configured to sense the compression force between the body member and the platform member during compression of the tissue between the anvil and the platform surface.

[0110] EMBODIMENT 5

[0111] The surgical instrument of embodiment 4, wherein the compression force sensor comprises an annular ring that surrounds at least a portion of the platform member during compression of the tissue between the anvil and the platform surface.

[0112] EMBODIMENT 6

[0113] The surgical instrument of any one or more of embodiments 1-3, wherein the first housing comprises an outer sheath configured to surround at least a portion of the movable member, wherein the second housing comprises a body member configured to surround at least a portion of the movable member, wherein the outer sheath is fixed relative to the body member, wherein the compression force sensor is configured to sense the compression force between the outer sheath and the body member during compression of the tissue between the anvil and the platform surface.

[0114] EMBODIMENT 7

[0115] The surgical instrument of any one or more of embodiments 1-3, wherein the first housing comprises a handle assembly configured to be grasped by a user, wherein the second housing comprises an outer sheath configured to surround at least a portion of the movable member, wherein the handle assembly is fixed relative to the outer sheath, wherein the compression force sensor is configured to sense the compression force between the handle assembly and the outer sheath during compression of the tissue between the anvil and the platform surface.

[0116] EMBODIMENT 8

[0117] The surgical instrument of any one or more of embodiments 1-3, wherein the first housing comprises an actuator configured to translate the movable member, wherein the second housing comprises a handle assembly configured to be grasped by a user, wherein the compression force sensor is configured to sense the compression force between the actuator and the handle assembly during at least one of compressing tissue between the anvil and the deck surface or firing the surgical instrument.

[0118] EMBODIMENT 9

[0119] The surgical instrument of any of the preceding embodiments, wherein the anvil comprises a head and a shaft, wherein the shaft is configured to selectively couple with the movable member to compress tissue between the anvil and the deck surface, wherein the tension sensor is coupled with the movable member or the shaft of the anvil.

[0120] EMBODIMENT 10

[0121] The surgical instrument of any of the preceding embodiments, wherein the movable member comprises a trocar actuation link assembly, wherein the tension sensor is fixedly coupled with the trocar actuation link assembly.

[0122] EMBODIMENT 11

[0123] The surgical instrument of embodiment 10, wherein the trocar actuation link assembly comprises an upper tension band and a lower tension band, wherein the tension sensor is fixedly coupled with the upper tension band.

[0124] EMBODIMENT 12

[0125] The surgical instrument of any of the preceding embodiments, wherein the tension sensor comprises an embedded strain gauge.

[0126] EMBODIMENT 13

[0127] The surgical instrument of any one or more of embodiments 1-9 and 12, wherein the movable member comprises a trocar actuation link assembly and a trocar, wherein the trocar is translatably coupled with the trocar actuation link assembly, wherein the tension sensor is disposed on the trocar actuation link assembly, the trocar, or between the trocar actuation link assembly and the trocar.

[0128] EMBODIMENT 14

[0129] The surgical instrument of any of the preceding embodiments, further comprising a control system, wherein the force sensing assembly comprises a wire electrically connecting at least one of the tension sensor or the compression force sensor with the control system.

[0130] EMBODIMENT 15

[0131] The surgical instrument of embodiment 14, wherein the control system comprises a user display feature, wherein the control system is electrically coupled with the user display feature, wherein the user display feature is configured to at least one of display the compression force or tension, display whether the compression force or tension is within an acceptable range, record the compression force or tension, or upload the compression force or tension to the cloud.

[0132] EMBODIMENT 16

[0133] A surgical instrument comprising: (a) a handle assembly, wherein the handle assembly comprises a housing; (b) a shaft assembly extending distally from the handle assembly, wherein the shaft assembly comprises an outer sheath, a trocar actuation rod, and a trocar actuation link assembly; (c) a stapling head assembly extending distally from the shaft assembly, wherein the stapling head assembly comprises: (i) a body member, (ii) a deck member comprising an annular array of staple openings, and (iii) a trocar; (d) an anvil comprising a head and a shaft, wherein the shaft is configured to selectively couple with the trocar to compress tissue; (e) an actuator configured to translate the trocar relative to the handle assembly; and (f) a force sensing assembly, wherein the force sensing assembly comprises: (i) a compression force sensor configured to sense a compression force transmitted longitudinally through the surgical instrument, wherein the compression force sensor is positioned between: (1) the deck member and the body member, (2) the body member and the outer sheath, (3) the outer sheath and the housing, or (4) the housing and the actuator, or (ii) a tension sensor coupled with at least one of the trocar actuation rod, the trocar actuation link assembly, the trocar, or the shaft of the anvil, wherein the tension sensor is configured to sense a tension transmitted longitudinally through the shaft assembly, the trocar, or the anvil.

[0134] EMBODIMENT 17

[0135] A method of using a surgical instrument comprising: a housing assembly comprising: a first housing and a second housing disposed adjacent to each other, and a deck surface comprising at least one annular array of staple openings; a movable member at least partially disposed within the housing assembly; an anvil configured to selectively couple with the movable member; and at least one of a compression force sensor or a tension force sensor, the method comprising: (a) compressing tissue between the anvil and the deck surface; (b) firing the surgical instrument to drive staples through the tissue; (c) at least one of: (i) using a compression force sensor disposed between the first housing and the second housing to measure a compression force transmitted longitudinally through the housing assembly between the first housing and the second housing in at least one of compressing tissue between the anvil and the deck surface or firing the surgical instrument, or (ii) using a tension force sensor coupled with the movable member to measure a tension force transmitted longitudinally through the movable member in at least one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument; and (d) determining at least one of: (i) a force at a time prior to the surgical instrument firing that the surgical instrument compressed tissue disposed between the deck surface and the anvil, or (ii) a force at which to actuate a firing assembly of the surgical instrument to fire the surgical instrument on the compressed tissue based on at least one of the compression force or the tension force.

[0136] EMBODIMENT 18

[0137] The method of any one or more of embodiments 17, further comprising generating an indication that the tissue compression is within an acceptable range after determining the tissue compression.

[0138] EMBODIMENT 19

[0139] The method of any one or more of embodiments 17 to 18, wherein the measuring step further comprises using an algorithm to correlate the measurement of the compression force or the tension force to an amount of tissue compression prior to the surgical instrument firing or during the surgical instrument firing.

[0140] EMBODIMENT 20

[0141] The method of any one or more of embodiments 17 to 19, further comprising uploading at least one of the forces to a cloud after determining the at least one of the forces.

[0142] IV. Miscellaneous

[0143] It should also be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein can be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. The above-described teachings, expressions, embodiments, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable methods, features, components, and / or functions described herein can be employed in conjunction with each other, without necessarily being out of context. Such modifications and variations are intended to be included within the scope of the claims.

[0144] The teachings disclosed herein can be combined with any one of the teachings of U.S. Patent Application [Attorney Docket No. END9260USNP1], entitled “Load Sensor for Circular Surgical Stapler,” filed on even date herewith, the disclosure of which is incorporated by reference herein.

[0145] Further, any one or more of the teachings, expressions, embodiments, examples, etc. described herein can be combined with any one or more of the teachings of U.S. Patent Application 16 / 574,797, entitled “Method for Controlling Cutting Member Actuation for Powered Surgical Stapler,” filed on September 18, 2019; U.S. Patent Application 16 / 574,281, entitled “Method for Controlling End Effector Closure for Powered Surgical Stapler,” filed on September 18, 2019; and U.S. Patent Application 16 / 574,299, entitled “Anvil Retention and Release Features for Powered Circular Surgical Stapler,” filed on September 18, 2019. The disclosure of each of these U.S. Patent Applications is incorporated by reference herein.

[0146] It should be understood that any patents, patent publications, or other publications referred to herein are hereby incorporated by reference in their entirety unless otherwise indicated. It should be understood that any discussion or disclosure involving a patent, patent publication or other disclosure provided herein is intended only to add context for the claimed application and should not be taken as an admission that any of the material described is prior art with respect to the claimed application.

[0147] Versions of the devices described above can have application in conventional medical treatments and procedures conducted by a medical professional, as well as application in robotic-assisted medical treatments and procedures. By way of example only, various teachings herein can be readily incorporated into a robotic surgical system such as the DAVINCI® TM system by Intuitive Surgical, Inc., of Sunnyvale, California.

[0148] The versions described above can be designed to be disposed of after a single use, or they can be designed to be used multiple times. Versions may, in either or both cases, be reconditioned for reuse after at least one use. Reconditioning can include an combination of the steps of disassembly of the device, followed by cleaning and / or replacement of particular pieces, and subsequent reassembly. In particular, some versions of the device can be disassembled, and certain parts of the device can be selectively replaced or removed in any combination. Upon cleaning and / or replacement of particular parts, some versions of the device can be reassembled for subsequent use either at a reconditioning facility, or by a user immediately prior to a procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0149] By way of example only, versions described herein can be sterilized before and / or after a procedure. In one sterilization technique, the device is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and device can then be placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation can kill bacteria on the device and in the container. The sterilized device can then be stored in the sterile container for later use. A device can also be sterilized using any other technique known in the art, including but not limited to beta or gamma radiation, ethylene oxide, or steam.

[0150] Having shown and described various embodiments of the present application, further adaptations of the methods and systems described herein can be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present application. Several of such possible modifications have already been mentioned, and others will be apparent to those skilled in the art. For instance, the embodiments, implementations, geometries, materials, dimensions, ratios, steps, and the like discussed above are illustrative and not mandatory. Accordingly, the scope of the present application should be considered in terms of the following claims, and it is understood that no limitation on the scope of the specification and the drawings is intended.

Claims

1. A surgical instrument (500), comprising: (a) a housing assembly (518), comprising: (i) a first housing, (ii) a second housing disposed adjacent to the first housing, and (iii) a deck surface (538) comprising at least one annular array of staple openings (556); (b) a movable member (520) disposed at least partially within the housing assembly; (c) an anvil (514) configured to selectively couple with the movable member to compress tissue between the anvil and the deck surface; and (d) a force sensing assembly (502), wherein the force sensing assembly comprises at least one of: (i) a compression force sensor (504) disposed between the first housing and the second housing, wherein the compression force sensor is configured to sense a pre-fire tissue compression force transmitted longitudinally through the first housing and the second housing during compression of the tissue between the anvil and the deck surface and a firing force transmitted longitudinally through the first housing and the second housing during firing of the surgical instrument, or (ii) a tension sensor (506) coupled with the movable member, wherein the tension sensor is configured to sense a tension force transmitted longitudinally through the movable member during compression of the tissue between the anvil and the deck surface and during firing of the surgical instrument, wherein the tension sensor is further configured to back-calculate a pre-fire tissue compression force and a firing force.

2. The surgical instrument of Claim 1, wherein, The force sensing assembly comprises the compression force sensor disposed between the first housing and the second housing.

3. The surgical instrument of Claim 2, wherein, The compression force sensor comprises a load cell.

4. The surgical instrument of Claim 2, wherein, The first housing comprises a body member (546) configured to surround at least a portion of the movable member, wherein the second housing comprises a deck member (540), wherein the deck member comprises the deck surface.

5. The surgical instrument of claim 4, wherein, The compression force sensor comprises an annular ring (548) that surrounds at least a portion of the deck member during compression of the tissue between the anvil and the deck surface.

6. The surgical instrument of claim 2, wherein, The first housing comprises an outer sheath (544) configured to surround at least a portion of the movable member, wherein the second housing comprises a body member (546) configured to surround at least a portion of the movable member, wherein the outer sheath is fixed relative to the body member.

7. The surgical instrument of Claim 2, wherein, The first housing comprises a handle assembly (508) configured to be grasped by a user, wherein the second housing comprises an outer sheath (544) configured to surround at least a portion of the movable member, wherein the handle assembly is fixed relative to the outer sheath.

8. The surgical instrument of claim 2, wherein, The first housing comprises an actuator (516) configured to translate the movable member, wherein the second housing comprises a handle assembly (508) configured to be grasped by a user.

9. The surgical instrument of Claim 1, wherein, The anvil includes a head (530) and a shaft (532), wherein the shaft is configured to be selectively coupled with the movable member to compress tissue between the anvil and the deck surface, wherein the tension sensor is coupled with the movable member.

10. The surgical instrument of claim 9, wherein, The movable member includes a trocar actuation link assembly, wherein the tension sensor is fixedly coupled with the trocar actuation link assembly.

11. The surgical instrument of claim 10, wherein, The trocar actuation link assembly includes an upper tension band and a lower tension band (606, 608), wherein the tension sensor is fixedly coupled with the upper tension band.

12. The surgical instrument of claim 9, wherein, The tension sensor includes an embedded strain gauge (612).

13. The surgical instrument of Claim 9, wherein, The movable member includes a trocar actuation band assembly (594), a trocar actuation rod (592), and a trocar (522), wherein the trocar is translationally coupled with the trocar actuation band assembly, wherein the tension sensor is disposed on the trocar actuation band assembly, the trocar, the trocar actuation rod, or between the trocar actuation band assembly and the trocar.

14. The surgical instrument of claim 1, further comprising a control system (524), wherein, The force sensing assembly includes a wire (528) electrically connecting at least one of the tension sensor or the compression force sensor with the control system.

15. The surgical instrument of claim 14, wherein, The control system includes a user display feature, wherein the control system is electrically coupled with the user display feature, wherein the user display feature is configured to at least one of display a compression force or a tension, display whether a compression force or a tension is within an acceptable range, record a compression force or a tension, or upload a compression force or a tension to a cloud.

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