Compression Force Sensor and Firing Force Sensor for Circular Surgical Stapler

Abstract

The 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 sensor coupled to 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 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 Art

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

[0002] Some circular staplers may include an electric operating mechanism. Examples of circular staplers with an electric operating mechanism are described in U.S. Patent Application Publication No. 2015 / 0083772, published on March 26, 2015, with the title "Surgical Stapler with Rotary Cam Drive and Return" (now abandoned); U.S. Patent No. 9,936,949, issued on March 26, 2015, with the title "Surgical Stapling Instrument with Drive Assembly Having Toggle Features"; U.S. Patent No. 9,907,552, issued on March 6, 2018, with the title "Control Features for Motorized Surgical Stapling Instrument"; and U.S. Patent No. 9,713,469, issued on July 25, 2017, with the title "Surgical Stapler with Rotary Cam Drive". The disclosure of each of the above-cited U.S. patent applications and U.S. patents is incorporated herein by reference.

[0003] Various types of surgical stapling instruments and related components have been manufactured and used, but it is believed that none of the inventors before us have made or used the invention described in the appended claims.

Brief Description of the Drawings

[0004] This specification concludes with the claims that particularly point out and distinctly claim the technology, but the technology is better understood when read in conjunction with the following description of certain specific embodiments in the accompanying drawings, in which like reference numerals identify like elements.

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[0005] The drawings are not intended to limit in any way, and it is contemplated that various embodiments of the present technology can be implemented in various other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated herein and forming a part of this specification illustrate some aspects of the present technology and are useful in explaining the principles of the present technology together with the description, but it is understood that the present technology is not limited to the exact arrangements shown.

Best Mode for Carrying Out the Invention

[0006] The following description of specific embodiments of the present technology should not be used for the purpose of limiting its scope. Other embodiments, features, aspects, embodiments, and advantages of the present technology will become apparent to those skilled in the art from the following description, which is one of the best modes contemplated for practicing the present technology by way of example. As will be understood, the technologies described herein are capable of other different and obvious aspects without departing from the technology. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0007] For the sake of clarity in this disclosure, the terms "proximal" and "distal" are defined with respect to a surgeon or other operator who holds a surgical instrument having a distal surgical end effector. The term "proximal" refers to the position of an element that is closer to the surgeon, and the term "distal" refers to the position of an element that is closer to and farther from the surgeon than the surgical end effector of the surgical instrument. Also, to the extent that spatial terms such as "above", "below", "upper", "lower", "vertical", "horizontal", etc. are used herein with reference to the drawings, it will be understood that such terms are used for illustrative descriptive purposes only and are not intended to be limiting or absolute in any way. In that regard, it will be understood that a surgical instrument such as that disclosed herein may be used in various orientations and positions not limited to those illustrated and described herein.

[0008] I. Overview of an Exemplary Circular Surgical Stapling Instrument Figures 1-2 show an exemplary circular surgical stapling instrument (10) that can be used to provide end-to-end, side-to-side, or end-to-side anastomosis between two cross-sections of an anatomical lumen, such as a portion of a patient's gastrointestinal 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 the 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. The instrument (10) further includes a removable battery pack (120) operable to power a motor (160) housed within the handle assembly (100), as will be described in more detail below.

[0009] The shaft assembly (200) extends distally from the handle assembly (100) and includes a pre-formed bend. The stapling head assembly (300) is disposed at the distal end of the shaft assembly (200). As shown in Figures 1-2 and as will be described in more detail later, the anvil (400) is configured to removably couple to the shaft assembly (200) adjacent to the stapling head assembly (300). Also, as will be described in more detail later, the anvil (400) and the stapling head assembly (300) are configured to cooperate in three ways to manipulate tissue, including clamping the tissue, cutting the tissue, and stapling the tissue. A knob (130) provided at the proximal end of the handle assembly (100) is rotatable relative to the casing (110) and is adapted to accurately clamp tissue between the anvil (400) and the stapling head assembly (300). When the safety trigger (140) of the handle assembly (100) pivots away from the firing trigger (150) of the handle assembly (100), the firing trigger (150) can be actuated such that the tissue is cut and stapled.

[0010] A. Exemplary Anvil As best shown in FIG. 3, the anvil (400) of this embodiment includes a head (410) and a shank (420). The head (410) includes a proximal surface (412) that defines a plurality of staple forming pockets (414). The staple forming pockets (414) are arranged in two rows of concentric annular arrays in this embodiment. The staple forming pockets (414) are configured to deform the staple when the staple is driven into the staple forming pocket (414). The proximal surface (412) terminates at an inner edge (416), thereby defining an outer boundary line of an annular recess (418) that surrounds the shank (420).

[0011] The shank (420) defines a hole (422) and includes a pair of pivot latch members (430). The latch members (430) are positioned within the hole (422) such that the distal end (434) is positioned at the proximal end of a lateral opening (424) formed through the side wall of the shank (420). In this way, the latch members (430) serve as retaining clips. Thereby, the anvil (400) can be removably fixed to an operable closure member in the form of a trocar (330) of the staple fastening head assembly (300), as will be described in more detail later.

[0012] B. Exemplary Staple Fastening Head Assembly As best shown in FIGS. 4 and 5, the staple fastening head assembly (300) of this embodiment is coupled to the distal end of the shaft assembly (200) and includes a body member (310) and a staple driver member (350) slidably received therein. The body member (310) includes a cylindrically shaped inner core member (312) that extends distally. 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) function together as a mechanical ground for the staple fastening head assembly (300).

[0013] The trocar (330) is coaxially positioned within the inner core member (312) of the body member (310). As will be described in more detail later, 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 casing (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 a proximally extending inner surface (338). The head (334) and the distal portion of the shaft (332) are configured to be inserted into the hole (422) of the anvil (400). The inner surface (338) and the latch shelf (436) have complementary positions and configurations such that the latch shelf (436) engages the inner surface (338) when the shank (420) of the anvil (400) is fully seated on the trocar (330). Accordingly, the anvil (400) is secured to the trocar (330) via a snap fit provided by the latch member (430).

[0014] The staple driver member (350) is operable to act longitudinally within the body member (310) in response to activation of the motor (160), as will be described in more detail later. The staple driver member (350) of the present embodiment includes two concentric annular arrays presented distally of the staple driver (352). The staple driver (352) is arranged to correspond to the arrangement of the staple forming pockets (414) of the anvil (400). Accordingly, each staple driver (352) is configured to drive a corresponding staple into the corresponding staple forming pocket (414) when the staple fastening head assembly (300) is actuated. The staple driver member (350) also defines a hole (354) configured to coaxially receive the core member (312) of the body member (310). An annular array of studs (356) projects distally from a distally presented surface surrounding the hole (354).

[0015] The cylindrical knife member (340) is positioned coaxially within the staple driver member (350). The knife member (340) includes a sharp, circular cutting edge (342) presented distally. The knife member (340) is sized to define an outer diameter smaller than the diameter defined by the inner annular array of the staple driver (352). The knife member (340) also defines an opening configured to coaxially receive the core member (312) of the body member (310). The annular array of openings (346) formed in the knife member (340) is configured to complement the annular array of studs (356) of the staple driver member (350), and the knife member (340) is fixedly secured to the staple driver member (350) immovably via the studs (356) and the openings (346).

[0016] The deck member (320) is fixedly secured to the distal end of the body member (310). The deck member (320) includes a distally directed deck surface (322) that defines a two-row concentric annular array of staple openings (324). The staple openings (324) are arranged to correspond to the arrangement of the aforementioned staple driver (352) and staple forming pocket (414). Thus, each staple opening (324) is configured to provide a path for the corresponding staple driver (352) to drive a corresponding staple through the deck member (320) and into the corresponding staple forming pocket (414) when the staple fastening head assembly (300) is actuated. As best shown in FIG. 9, the deck member (320) defines an inner diameter that is slightly larger than the outer diameter defined by the knife member (340). Thus, the deck member (320) is configured to allow the knife member (340) to translate distally to a point where the cutting edge (342) is distal to the distal end of the deck surface (322).

[0017] C. Representative Shaft Assembly FIG. 6 shows various components of a shaft assembly (200) that couples components of a staple head assembly (300) to components of a handle assembly (100). In particular, and as noted above, the shaft assembly (200) includes an outer sheath (210) that extends between the handle assembly (100) and the body member (310). The shaft assembly (200) further includes a trocar actuating rod (220) and a trocar actuating band assembly (230). The distal end of the trocar actuating band assembly (230) is fixedly secured to the proximal end of a trocar shaft (332). The proximal end of the trocar actuating band assembly (230) is fixedly secured to the distal end of the trocar actuating rod (220). Thus, it should be understood that the trocar (330) translates longitudinally relative to the outer sheath (210) in response to translation of the trocar actuating band assembly (230) and the trocar actuating rod (220) relative to the outer sheath (210). A clip (222) is fixedly secured to the trocar actuating rod (220) and is configured to cooperate with complementary features within the handle assembly (100) to prevent rotation of the trocar actuating rod (220) within the handle assembly (100) while allowing longitudinal translation of the trocar actuating rod (220) within the handle assembly (100). The trocar actuating rod (220) further includes a coarse helical thread portion (224) and a fine helical thread portion (226).

[0018] The shaft assembly (200) further includes a staple head assembly driver (240) slidably received within an outer sheath (210). The distal end of the staple head assembly driver (240) is fixedly secured to the proximal end of a staple driver member (350). The proximal end of the staple head assembly driver (240) is secured to a drive bracket (250) via a pin (242). Thus, it should be understood that the staple driver member (350) translates longitudinally with respect to the outer sheath (210) in response to translation of the staple head assembly driver (240) and the drive bracket (250) relative to the outer sheath (210).

[0019] D. Exemplary Handle Assembly and User Input Mechanism As shown in FIG. 1, the handle assembly (100) includes a casing (110) that has a lower portion defining an obliquely oriented pistol grip (112) and an upper portion that supports a user interface mechanism portion (114) and receives a battery pack (120), as will be described in further detail below. The handle assembly (100) further includes several mechanisms operable to actuate an anvil (400) and a staple 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 to a trocar actuating rod (220) via a nut (not shown), and a coarse helical thread (224) selectively engages a screw engagement mechanism portion inside the nut, and a fine helical thread (226) selectively engages a screw engagement mechanism portion inside the knob (130). These complementary structures are configured such that the trocar actuating rod (220) first translates proximally at a relatively slow speed and then translates proximally at a relatively fast speed in response to rotation of the knob (130).

[0020] It should be understood that when the anvil (400) is coupled to the trocar (330), rotation of the knob (130) correspondingly causes the anvil (400) to translate relative to the staple head assembly (300). The knob (130) can be rotated in a first angular direction (e.g., clockwise) to retract the anvil (400) toward the staple head assembly (300), and rotated in a second angular direction (e.g., counterclockwise) to advance the anvil (400) away from the staple head assembly (300). Thus, the knob (130) can be used to adjust the gap distance (d) between the opposing surfaces (412, 322) of the anvil (400) and the staple head assembly (300), as shown, for example, in FIG. 7C described below, until a suitable gap distance (d) is achieved.

[0021] The firing trigger (150) is operable to activate a motor (160), thereby activating the staple head assembly (300). The safety trigger (140) is operable to selectively block the activation of the firing trigger (150) based on the longitudinal position of the anvil (400) relative to the staple head assembly (300). The handle assembly (100) also includes components operable to selectively lock out both triggers (140, 150) based on the position of the anvil (400) relative to the staple head assembly (300). For example, the safety trigger (140) can be prevented from rotating from an engaged position to a disengaged position until the position of the anvil (400) relative to the staple head assembly (300) is within a predefined range. Thus, activation of the firing trigger (150) is blocked by the safety trigger (140) until the anvil position is within the predefined range, thereby preventing firing of the staple head assembly (300).

[0022] When the firing trigger (150) pivots to the fired position, the firing trigger (150) is operable to actuate a switch of the motor activation module (180) (FIG. 1). Since the motor activation module (180) is in communication with the battery pack (120) and the motor (160), the motor activation module (180) is configured to activate the motor (160) with power from the battery pack (120) in response to actuation of the switch of the motor activation module (180) by the paddle. Thus, the motor (160) is activated when the firing trigger (150) pivots. As will be described in more detail later, activation of this motor (160) causes the staple head assembly (300) to be actuated via the drive bracket (250). As best shown in FIGS. 1-2, the handle assembly (100) is further configured to releasably receive a battery pack (120) operable to supply power to the motor (160) as described above.

[0023] E. Exemplary Anastomosis Procedure Using a Circular Stapling Instrument FIGS. 7A-7E illustrate an instrument (10) used to form an anastomosis (70) between two tubular anatomical structures (20, 40). By way of example only, the tubular anatomical structures (20, 40) can include regions of a patient's esophagus, regions of a patient's colon, other regions of a patient's gastrointestinal tract, or any other tubular anatomical structure.

[0024] As shown in FIG. 7A, the anvil (400) is positioned within one of the tubular anatomical structures (20), and the stapling head assembly (300) is positioned within the other tubular anatomical structure (40). As shown in FIG. 7A, the anvil (400) is positioned within the tubular anatomical structure (20) such that the shank (420) protrudes from the open cut end (22) of the tubular anatomical structure (20). In this embodiment, the purse string suture (30) is provided around the central region of the shank (420) to substantially fix the position of the anvil (400) within the tubular anatomical structure (20). The stapling head assembly (300) is positioned within the tubular anatomical structure (40) such that the trocar (330) protrudes from the open cut end (42) of the tubular anatomical structure (20). A purse string suture (50) is provided around the central region of the shaft (332) to generally secure the position of the stapling head assembly (300) within the tubular anatomical structure (40). The stapling head assembly (300) is then urged distally to ensure that the stapling head assembly (300) is fully seated at the distal end of the tubular anatomical structure (40).

[0025] Next, as shown in FIG. 7B, by inserting the trocar (330) into the hole (422), the anvil (400) is fixed to the trocar (330). The latch 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 casing (110) stationary via the pistol grip (112). Rotation of this knob (130) causes the trocar (330) and the anvil (400) to retract proximally. As shown in FIG. 7C, this proximal retraction of the trocar (330) and the anvil (400) compresses the tissue of the tubular anatomical structure (20, 40) between the surfaces (412, 322) of the anvil (400) and the staple head assembly (300). When this occurs, the operator can observe the tactile resistance or feedback via the knob (130) while pivoting the knob (130), such tactile resistance or feedback indicating that the tissue is being compressed. When the tissue is compressed, the operator can visually observe the position of the indicator needle (522) within the user interface mechanism portion (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 staple head assembly (300) is appropriate and, if adjustment is necessary, make the necessary adjustment via the knob (130).

[0026] After the operator properly sets the gap distance (d) via the knob (130), the operator pivots the safety trigger (140) towards the pistol grip (112) to enable the actuation of the firing trigger (150). Next, the operator pivots the firing trigger (150) towards the pistol grip (112), thus causing the paddle (158) to actuate the switch of the motor activation module (180), thereby starting and rotating the motor (160). Such rotation of the motor (160), as shown in FIG. 7D, actuates the drive bracket (250) distally, thereby causing the actuation (or "firing") of the staple head assembly (300) by driving the knife member (340) and the staple driver member (350) distally. As 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 inside the knife member (340).

[0027] As shown in FIG. 3, the anvil (400) of the present embodiment includes a release washer (417) positioned within the annular recess (418). When the knife member (340) moves fully distally through its entire range of motion from the position shown in FIG. 7C to the position shown in FIG. 7D, this washer (417) is broken by the knife member (340). In the variant form that includes the washer (417), it should be understood that the washer (417) can also serve as a cutting board for the knife member (340) to assist in tissue cutting. As the staple driver member (350) translates distally from the position shown in FIG. 7C to the position shown in FIG. 7D, the staple driver member (350) drives the staple (90) through the tissue of the tubular anatomical structure (20, 40) and into the staple forming pocket (414) of the anvil (400). The staple forming pocket (414) deforms the driven staple (90) into, for example, a "B" shape or a three-dimensional shape, such that the formed staple (90) fixes the ends of the tissue to each other, thereby joining the tubular anatomical structure (20) to the tubular anatomical structure (40).

[0028] As shown in FIG. 7D, after the operator activates the staple head assembly (300), the operator rotates the knob (130) to drive the anvil (400) distally away from the staple head assembly (300) to increase the gap distance (d) and facilitate the release of the tissue between the surfaces (412, 322). Next, the operator removes the instrument (10) from the patient while the anvil (400) is still fixed to the trocar (330). When the instrument (10) is removed, the tubular anatomical structures (20, 40) are left secured together by the two rows of annular arrays of staples (90) at the anastomosis (70), as shown in FIG. 7E. The inner diameter of the anastomosis (70) is defined by the severed edges (60) left by the knife member (340).

[0029] II. Exemplary Circular Surgical Stapling Instrument with Force Sensing Assembly A. Overview Applying an appropriate amount of pre - firing tissue compression (i.e., tissue compression before firing) and / or an appropriate amount of force to fire the instrument (10) can improve staple formation. As used herein, firing is the distal actuation of the staples and knife (e.g., knife member (340)) into the clamped tissue, and pre - firing tissue compression is the tissue compression that occurs before firing (i.e., the distal actuation of the staples and knife into the clamped tissue). The pre - firing tissue compression of the instrument (10) is generally depicted in FIG. 7C above, and the firing of the instrument (10) is generally depicted in FIG. 7D above. Applying an appropriate amount of force can be beneficial for both manual and powered circular staplers. Additionally, it may be desirable to monitor such forces experienced by and communicated through the instrument (10) to evaluate their impact on the performance and lifespan of the instrument (10). Thus, it would be beneficial to use actual data from the instrument (10) to determine the pre - firing tissue compression force and / or the force to fire the instrument (10) when the thickness of the tissue can vary from patient to patient and the desired amount of compression force can vary.

[0030] Also, it may be desirable to provide a variant of the circular surgical stapling instrument (10) that determines the pre-firing tissue compression force and / or the force to fire the instrument (10), communicates this information to the user, and / or combines that information with other information from other stapling procedures. By acquiring real-time data, it may be possible for the user to take actions to improve staple formation. Additionally, by evaluating data from multiple instruments, trends may be identified and changes may be able to be implemented. Thereby, the instrument (10) may be able to provide a more consistent pre-firing tissue compression force and / or force for firing. Thus, measuring and tracking the pre-firing tissue compression force and / or the force with which the instrument (10) fires may be beneficial to the user(s) during the procedure and after the procedure.

[0031] Furthermore, it may be desirable to provide such a variant of the instrument (10) that determines this data without directly measuring the pre-firing tissue compression force and the force to fire at the distal end of the instrument (10). By indirectly measuring the actual pre-firing tissue compression force and / or the force to fire, the need to route one or more wires through at least a portion of the shaft assembly (200) and the stapling head assembly (300) to connect sensors and a control system may be eliminated. For example, it may 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). Thus, it may be further desirable to place one or more sensors outside the distal end of the instrument (10) and use the analysis of the actual tension and compression forces experienced by the instrument (10) to indirectly determine the pre-firing tissue compression force and / or the force to fire.

[0032] The following description provides some examples of variants of the instrument (10) that provide the various force sensing mechanisms and capabilities described above.

[0033] B. Exemplary Circular Surgical Stapling Instrument Figures 8-15 show another exemplary circular surgical stapling instrument (500) presenting the above-described type of configuration and functionality. It will be understood that the instrument (500) is similar to the above-described instrument (10), except as otherwise described below. In particular, FIG. 8 shows a cross-sectional view of the instrument (500) similar to the instrument (10) of FIG. 1, but the instrument (500) additionally includes a force sensing assembly (502).

[0034] Similar to the instrument (10), the instrument (500) includes a body assembly in the form of a handle assembly (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 (similar to the knob (130)). The actuator may include other suitable alternatives including a manually slidable lever, or may be powered using a motor (160) or another similar motor. These components are similar to the respective components of the instrument (10) of the same name described above with reference to 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 the distal end of the shaft assembly (510).

[0035] As described in more 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 sensor (506) configured to sense a tension force experienced by the instrument (500). For example, the force sensing assembly (502) may include at least one compression force sensor (504), at least one tension sensor (506), or both at least one compression force sensor (504) and at least one tension sensor (506). The instrument (500) may be considered a system of compression and tension during tissue compression (i.e., clamping) and during firing of the instrument (500). When the anvil (514) clamps the compressed tissue, the components of the instrument (500) experience at least one of tension or compression. During firing, the magnitudes of these tension and compression forces of the instrument (500) increase.

[0036] As described in more detail below with reference to FIGS. 8-15, the instrument (500) includes a housing assembly (518) and a movable member (520), and the movable member (520) moves relative to the housing assembly (518) using an actuator (e.g., a knob (516)). An anvil (514) is coupled to a trocar (522) (similar to trocar (330)), and when the knob (130) is rotated by a user, the housing assembly (518) experiences a compressive force and the movable member (520) experiences a tensile force. The pull caused by the rotational input of the knob (516) moves the movable member (520), which includes the trocar (522), proximally. In other words, by applying a torque to close the gap (d) using the rotatable knob (516), the movable member (520) is pulled proximally, causing compressive and tensile forces. As a result, stress and / or strain can be measured in the instrument (500). As shown in FIG. 10, the housing assembly (518) is collectively defined by a handle assembly (508), a shaft assembly (510), a stapling head assembly (512), and the adjacent housing of the knob (516) that produces the compressive force. As shown in FIG. 14, the movable member (520) is collectively formed by portions of the trocar (522) of the shaft assembly (510) and the stapling head assembly (512).

[0037] C. Exemplary Control System The instrument (500) may include a control system (524) operable to control the operation of the instrument (500). The control system (524) may include associated circuitry that interfaces with a user interface mechanism (526), a motor unit, and a force sensing assembly (502). The compression force sensor (504) and the tension sensor (506) may be electrically coupled to the control system (524) using one or more wires (528). As described in more detail with reference to FIG. 15, the user interface mechanism (526) may indicate whether the sensed compression force and / or the sensed tension is within an acceptable range. The control system (524) may include a processor, a memory, and a printed circuit board. The control system (524) may be disposed within the instrument (500) or may be disposed outside the instrument (500) but communicate with the instrument (500) either wired or wirelessly. The control system (524) may be operable to store a pre-programmed instrument control algorithm and receive inputs from the user interface mechanism (526) and the force sensing assembly (502). Based on these stored control algorithms and the received inputs, the control system (524) is configured to determine tissue compression at the distal end of the instrument (500).

[0038] This tissue compression data can be processed by an integrated printed circuit board (PCB) of the instrument (500) and then uploaded to cloud storage for subsequent data analysis. For example, the average force of emission can be determined among other characteristics. Although not shown, the printed circuit board (PCB) can be disposed within a handle assembly (508) near a user interface feature (526). For example, a wire (528) can be routed to the PCB for resistance interpretation and correlation with the compression force. In some variations, at least one of the control system (524) or the user interface mechanism (526) can signal communicate with an external network such that the compression force data can be uploaded directly to the cloud for data interpretation. For example, the teachings disclosed herein may be combined with any of the teachings of U.S. Patent Application Publication No. 2019 / 0201136, titled "Method of Hub Communication," published on July 4, 2019, U.S. Patent Application Publication No. 2019 / 0206569, titled "Method of Cloud Based Data Analytics for Use with the Hub," published on July 4, 2019, U.S. Patent Application Publication No. 2020 / 0100830, titled "Method for Constructing and Using a Modular Energy System with Multiple Devices," and filed on April 2, 2020, and U.S. Provisional Patent Application No. 63 / 018,664, titled "Stabilizer for Surgical Shafts or Cannulas," filed on May 1, 2020, the disclosures of which are incorporated herein by reference. In some variations, the tissue compression data can be pushed to a desired smart connected device.

[0039] D. Exemplary Anvil Anvil (514) is similar to the anvil (400) described above with reference to FIG. 3. The anvil (514) is configured to be selectively coupled with a movable member (520) to clamp, staple, and cut tissue using a stapling head assembly (512). The anvil (514) and the stapling head assembly (512) are configured to cooperate to manipulate tissue in three ways: sandwiching the tissue, cutting the tissue, and stapling the tissue. The anvil (514) of this 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 the staple when the staple is driven into the staple forming pocket.

[0040] In particular, the anvil (514) selectively couples with a trocar (522) using a latch member (536) similar to the latch member (430). The latch member (536) acts as a retaining clip to enable the anvil (514) to be removably fixed to an operable 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 deck surface (538) facing distally of a deck member (540) (similar to the deck member (320)). When the anvil (514) is coupled with the trocar (522), rotation of the knob (516) correspondingly causes the anvil (514) to translate relative to the stapling head assembly (512).

[0041] E. Exemplary Compression Force Sensing Figure 9 shows a cross-sectional view of the housing assembly (518) of the instrument (500) of FIG. 8. As shown, the housing assembly (518) includes at least a first housing and a second housing of the instrument (500), and a deck surface (538). The first housing and the second housing are disposed adjacent to each other. In some variations, the first housing and the second housing are prevented from translating relative to each other. For example, in some variations, the first housing and the second housing can be fixedly coupled together in a fixable manner using various suitable methods. As shown, the force sensing assembly (502) includes at least one compression force sensor (504) disposed between the first housing and the second housing of the housing assembly (518). For example, the first housing and the second housing can include an actuator (shown as knob (516)), a casing (542) of the handle assembly (508), a deck member (540) (i.e., a guide), an outer sheath (544) (similar to the outer sheath (210)), and a body member (546) (similar to the body member (310)). The compression force sensor (504) is configured to sense a compression force (i.e., pre-firing tissue compression force) transmitted longitudinally through the housing assembly (518) while compressing the tissue between the anvil (514) and the deck surface (538) of the deck member (540), and / or a compression force (i.e., firing force) transmitted longitudinally through the firing of the instrument (500). As used herein, the pre-firing tissue compression force is the force experienced by the tissue when the tissue is near ready for firing by the instrument (500), and the firing force is the force experienced by the instrument (500) through a firing sequence (e.g., tissue cutting and stapling). 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., between the first housing and the second housing). The compression force sensor (504) can be electrically coupled to a control system (524) using one or more wires (528).

[0042] FIG. 10 shows an enlarged view of the distal end of the instrument (500) of FIG. 8, where a compression force sensor (504) is disposed between the deck member (540) and the body member (546) of FIG. 9. As shown, the compression force sensor (504) includes an annular ring (548) that surrounds at least a portion of the deck member (540). Although the compression force sensor (504) is shown as the annular ring (548) in FIG. 10, the compression force sensor (504) can take various suitable forms, and it is contemplated that the compression force sensor (504) can be non-annular. The compression force sensor (504) can sense the pre-firing tissue compression force between the body member (546) and the deck member (540). The annular ring (548) enables measuring the pre-firing tissue compression between the deck member (540) and the body member (546). As shown, the deck member (540) is movable relative to a body member (546) that is different from that described with reference to the instrument (10). Due to the loose fit of the annular ring (548), the deck member (540) can be selectively translated proximally to selectively apply pressure between the bottom surface (550) of the flange (552) of the deck member (540) and the distal end (554) of the body member (546). The deck member (540) is pressed toward the body member (546) to calculate the force on the tissue that is compressed prior to firing. As shown, an embedded electrical connection (shown as wire (528)) can be disposed within the body member (546) to electrically connect the annular ring (548) to a control system (524) (shown in FIG. 8). As shown, the deck member (540) includes a concentric annular array of staple openings (556) (similar to the staple openings (324)). In some other variations, the staple openings (556) can be arranged in a concentric annular array of three or more rows.

[0043] Figures 11-13 illustrate representative positions of a compression force sensor (504) disposed between a first housing and a second housing of a housing assembly (518). Figures 11-13 illustrate representative positions of the compression force sensor (504), although other suitable positions and arrangements of the compression force sensor (504) are contemplated. The first housing and the second housing may be joined together at a junction that experiences compression forces during pre-launch tissue compression and during firing of the instrument (500). As a result, it may be beneficial to include that one or more compression force sensors (504) may be disposed at these junctions. For example, the compression force sensor (504) is disposed between a body member (546) and an outer sheath (544). In each of Figures 11-13, the compression force sensor (504) may include a load cell.

[0044] FIG. 11 is a detailed portion of FIG. 9, where a compression force sensor (504) is disposed between the proximal end (558) of the outer sheath (544) and the distal end (560) of the body member (546). The compression force sensor (504) can be electrically coupled to the control system (524) using one or more wires (528). The compression force sensor (504) can sense the pre-firing tissue compression force between the outer sheath (544) and the body member (546). The body member (546) is configured to surround at least a portion of the movable member (520). The body member (546) includes a distally extending cylindrical inner core member (562) (similar to the inner core member (312)). The body member (546) is fixedly secured to the outer sheath (544) of the shaft assembly (510). The body member (546) and the outer sheath (544) together serve as a mechanical base for the staple 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 embodiment, the outer sheath (544) is rigid and includes a pre-formed curved region (564) (as shown in FIGS. 8-9). The instrument (500) also includes a ferrule (566) that surrounds at least a portion of the outer sheath (544), for example, as disclosed in U.S. Patent Application No. 16 / 887,182, filed May 29, 2020, entitled "Shaft Attachment Feature for Circular Surgical Stapler", the disclosure of which is incorporated herein by reference.

[0045] FIG. 12 is a detailed portion of FIG. 9 and shows a compression force sensor (504) disposed between the proximal end (568) of the outer sheath (544) and the internal fitting mechanism portion (570) of the casing (542) of the handle assembly (508). The compression force sensor (504) can sense the pre-firing tissue compression force between the proximal end (568) of the outer sheath (544) and the internal fitting mechanism portion (570) of the casing (542). The handle assembly (508) includes a casing (542). As shown in FIG. 9, the casing (542) includes a proximal end (572) and a distal end (574). The casing (542) also includes an obliquely oriented pistol grip (576), and the user interface mechanism portion (526) is disposed on the upper portion (578) of the casing (542) adjacent to the distal end (574) of the casing (542). The knob (516) is rotatably disposed at the proximal end (572) of the casing (542). The handle assembly (508) includes several mechanism portions 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 a motor (similar to (160)) housed within the handle assembly (508). The firing trigger (150) is configured to actuate the stapling head assembly (512) by activating the motor (160). The safety trigger (140) is configured to selectively block the actuation of the firing trigger (150) based on the longitudinal position of the anvil (514) relative to the stapling head assembly (512). As shown in FIG. 9, the casing (542) of the present embodiment includes an open-ended proximal cavity (580) configured to releasably receive and hold the battery pack (588) and operable to supply power to a motor (586) housed within the casing (542).

[0046] FIG. 13 is a detailed portion of FIG. 9 and shows a compression force sensor (504) disposed between the casing (542) of the handle assembly (508) and the knob (516). In particular, the compression force sensor (504) is disposed between the proximal end (572) of the casing (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., the knob (516)) and the casing (542) of the handle assembly (508), and / or the firing force between the actuator (e.g., the knob (516)) and the casing (542) of the handle assembly (508). The compression force sensor (504) can sense the compression force both during pre-firing tissue compression and during the firing sequence. The compression force sensor (504) can be electrically coupled to 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. Rotating the knob (516) in a first angular direction (e.g., clockwise) causes the anvil (514) to retract towards the staple head assembly (512), and rotating it in a second angular direction (e.g., counterclockwise) causes the anvil (514) to advance away from the staple head assembly (512). The knob (516) can be used to adjust the gap distance (d) between the proximal surface (534) of the anvil (514) and the deck surface (538) of the deck member (540) until a suitable gap distance (d) is achieved, as shown in FIG. 7C with respect to the instrument (10). The tension caused by the rotational input of the knob (516) moves the trocar (522) proximally. The knob (516) is rotatable relative to the casing (542) and provides an accurate clamp of the tissue between the anvil (514) and the deck member (540).

[0047] F. Tension Sensing FIG. 14 shows a perspective view of the moving member (520) of FIG. 8. The movable member (520) is configured to be actuated at least between an open position for receiving at least a first tissue layer and a second tissue layer and a closed position in which at least the first tissue layer and the second tissue layer are compressed against each other. The movable member (520) can be disposed at least partially within the handle assembly (518). As described above, the movable member (520) is collectively formed by the shaft assembly (510) and the trocar (522) portion of the stapling head assembly (512). As shown, the movable member (520) includes a trocar (522), a trocar actuating rod (592), and a trocar actuating connection assembly (shown as the trocar actuating band assembly (594)). At least one tension sensor (506) is coupled to the trocar actuating rod (592), the trocar actuating band assembly (594), and / or the trocar (522) to sense the tension of the trocar actuating rod (592), the trocar actuating band assembly (594), and / or the trocar (522). The tension sensor (506) is configured to sense the tension transmitted longitudinally through the movable member (520) and / or the trocar (522) while compressing the tissue between the anvil (514) and the deck surface (538) and / or the firing device (500). The tension sensor (506) can sense the tension during tissue compression prior to firing and during the firing sequence.

[0048] The trocar operating rod (592) has proximal and distal ends (596, 598) such that the proximal end (600) of the trocar operating band assembly (594) is fixed to the distal end (598) of the trocar operating rod (592). The proximal end (596) of the trocar operating rod (592) is coupled to the knob (516). The trocar operating rod (592) includes a coarse helical thread portion (602) and a fine helical thread portion (604). The knob (516) is coupled to the trocar operating rod (592) via a nut (not shown), and the coarse helical thread portion (602) selectively engages with the screw engagement mechanism portion inside the nut, and the fine helical thread portion (226) selectively engages with the screw engagement mechanism portion inside the knob (516). As shown, the tension sensor (506) can be coupled to the trocar operating rod (592) such that the tension sensor (506) can be electrically coupled to the control system (524) using one or more wires (528).

[0049] The tension sensor (506) can be coupled to the trocar operating band assembly (594). The trocar operating band assembly (594) can include a plurality of tension bands, which are shown as being stacked together. As shown in FIG. 14, the trocar operating band assembly (594) includes upper and lower tension bands (606, 608). In some variations, the upper and lower tension bands (606, 608) can be formed from a metallic material such that one of the upper and lower tension bands (606, 608) within the instrument (500) that retracts the anvil (514) against the tissue is under tension during tissue compression and firing where the knife presses on the anvil (514). The tension sensor (506) can be fixedly coupled to one of the upper and lower tension bands (606, 608).

[0050] As shown, the tension sensor (506) is fixedly coupled to the upper surface (610) of the upper tension band (606). The tension sensor (506) may include a strain gauge (612). For example, the strain gauge (612) may be positioned on the planar portion (614) of the upper tension band (606) of the trocar actuation band assembly (594) that is subjected to tension during tissue compression. The upper tension band (606) experiences a higher tension when the instrument (500) is fired, and this increase in strain is 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) may correlate the strain to the pre-firing tissue compression force and / or the firing force at the distal end of the instrument (500). The tension sensor (506) may be embedded in the upper surface (610) to measure surface strain and calculate the pre-firing tissue compression force and / or the firing force at the distal end of the instrument (500). Alternatively, the strain gauge (612) may include an in-line strain gauge. The in-line strain gauge may be placed between respective components of the movable member (520). For example, the in-line strain gauge may be placed where two components fit together. In some variations, 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)) may be removed and replaced with the in-line strain gauge. The trocar (522) is described below with reference to the in-line strain gauge (616).

[0051] As shown in FIG. 14, the tissue compression force and / or the firing force before firing can be measured using a tension sensor (506) coupled and disposed with a trocar (522) such that the tension sensor (506) can be electrically coupled to a control system (524) using one or more wires (528). The trocar (522) is operable to translate distally and proximally relative to a body member (546) in response to rotation of a knob (516) relative to a casing (542) of a handle assembly (508). The trocar (522) includes a shaft (618) and a head (620). The head (620) includes a pointed tip (622) and a proximally extending inner surface (624). The head (620) and the distal portion of the shaft (618) are configured to be inserted into a hole (similar to the hole (422) of the anvil (400) but not shown). Thus, the anvil (514) is fixed to the trocar (522) via a snap fit provided by a latch member (536). The latch member (536) of the anvil (514) captures the trocar (522) and causes a pull on an intermediate component of the movable member (520) (e.g., a trocar actuating rod (592), a trocar actuating band assembly (594)). The tissue compression force and / or the firing force before firing can be measured using a strain gauge (626) on the shaft (618) of the anvil (514).

[0052] As shown in FIG. 14, 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). Thus, it should be understood that as the trocar actuation band assembly (594) and the trocar actuation rod (592) translate relative to the outer sheath (544), the trocar (522) translates longitudinally relative to the outer sheath (544). The trocar actuation band assembly (594) is configured to bend such that as the trocar actuation band assembly (594) is translated longitudinally relative to the outer sheath (544), the trocar actuation band assembly (594) can move along a pre-formed curvature within the shaft assembly (510). However, the trocar actuation band assembly (594) has sufficient column strength and tensile strength to transmit forces in the distal and proximal directions from the trocar actuation rod (592) to the shaft (618) of the trocar (522). The trocar actuation rod (592) is rigid. The clip (632) is fixedly secured to the trocar actuation rod (592), and while allowing the trocar actuation rod (592) to translate longitudinally within the handle assembly (508), the clip (632) is configured to cooperate with complementary features within the handle assembly (508) to prevent the trocar actuation rod (592) from rotating within the handle assembly (508).

[0053] Similar to the staple head assembly (300), the staple head assembly (512) includes a deck member (540) and a trocar (522). The staple head assembly (512) is selectively operable to distally eject staples against an anvil (514) into clamped tissue and to cut the clamped tissue with a cylindrical knife member (not shown) similar to the knife member (340) described above. Thus, the staple head assembly (512) and the anvil (514) cooperate to define an end effector staple assembly operable to clamp, staple, and cut tissue in response to user input.

[0054] The instrument (500) may be further configured and operable in accordance with at least some of the teachings of U.S. Patent No. 9,445,816, issued September 20, 2016, titled "Circular Stapler with Selectable Motorized and Manual Control"; U.S. Patent No. 9,532,783, issued January 3, 2017, titled "Circular Stapler with Select Motorized and Manual Control, Including a Control Ring"; U.S. Patent No. 9,597,081, issued March 21, 2017, titled "Motor Driven Rotary Input Circular Stapler with Modular End Effector"; U.S. Patent No. 9,463,022, issued October 11, 2016, titled "Motor Driven Rotary Input Circular Stapler with Lockable Flexible Shaft"; U.S. Patent Application Publication No. 2018 / 0368836, published December 27, 2018, titled "Surgical Stapler with Independently Actuated Drivers to Provide Varying Staple Heights", and / or any of the other patent documents identified herein, the disclosures of which are hereby incorporated by reference herein.

[0055] G. Exemplary Manually Actuated Circular Stapler Although not shown, the force sensing assembly (502) can be incorporated into a manually actuated circular stapler instead of the instrument (500) shown as a powered circular stapler. For example, the force sensing assembly (502) can be applied to a manually actuated circular stapler such as those of the type described in U.S. Patent Application Publication No. 2020 / 0113565, published April 16, 2020, titled "Latch to Prevent Back-Driving of Circular Surgical Stapler", the disclosure of which is incorporated herein by reference. A power source (not shown) can be included in the force sensing assembly (502) for a manually actuated circular stapler. For example, the power source can be electrically coupled to a strain gauge.

[0056] H. Exemplary User Interface Mechanisms of the Handle Assembly FIG. 15 shows a perspective view of the user interface mechanism (526) of the handle assembly (508) of the instrument (500) of FIG. 8. The user interface mechanism (114) is configured to provide visual feedback to the operator indicating the positioning of the anvil (514) relative to the staple head assembly (512) during a surgical procedure. The operator can rotate the knob (516) and view the user interface mechanism (526) to confirm whether an appropriate gap distance (d) between the anvil (514) and the staple assembly (512) has been achieved. The user interface mechanism (526) of the present embodiment includes a graphical indicator (633) including stationary linear marks (634, 636, 638), graphical representations of staples (640, 642), and a checkmark graphic (644). The user interface mechanism (114) further defines a window (646) through which the indicator needle (648) can be viewed. The circular surgical stapling instrument (500) can further be configured and operable in accordance with at least some of the teachings of U.S. Patent No. 10,709,452, issued July 14, 2020, incorporated by reference above.

[0057] The user interface mechanism (526) is configured to receive user input and communicate it to the control system (524). In that regard, the user interface mechanism (526) may include one or more buttons, dials, other operable elements, or display graphics selectable by the user to indicate specific information regarding the surgical procedure or staple head assembly (512) being performed. By way of mere example, such information may include any of the following, namely, the desired staple forming height, the anvil (514) to be actuated during closure, the corresponding gap between the anvil (514) and the staple head assembly (512), the type or nominal thickness of tissue to be fired by the instrument (500), and / or the diameter of the staple head assembly (512). When the operator rotates the knob (516) to adjust the longitudinal position of the anvil (514) relative to the staple head assembly (512), the operator can view the tissue compression force actively sensed by the instrument (500).

[0058] This information can be provided to the surgeon in real-time display (variable or attribute) to ensure that tissue compression is uniform. In some variations, the user interface mechanism (526) can display the compression force to the user. For example, the user interface mechanism (526) can include a tissue compression screen (650). The user can be notified of the tissue compression force before firing using an LED panel. The compression force before firing can be presented as an individual pass / fail signal (e.g., a colored indicator such as green and red light) or as a quantitative readout. For example, strain data can be processed to determine the tissue compression force before firing and / or the force during the firing stroke at the distal end of the instrument (500). Alternatively, or in addition to the user interface mechanism (526), the instrument (500) can communicate signal with an external network, and the tissue compression force before firing and / or the force during the firing can be directly uploaded to the cloud for data interpretation to determine the relevant tissue compression force before firing and / or the force during the firing stroke at the distal end of the instrument (500). Additionally, the tissue compression force before firing and / or the force of the firing data can be recorded for real-time field monitoring and to prevent trends. The compression force can be obtained from a strain gauge, and the correlation can be formulated to determine the tensile values of the tissue compression and the force during the firing corresponding to the tissue compression force before firing and / or the force during the firing at the distal end of the instrument (500).

[0059] I. Exemplary Method Referring to FIG. 16, an exemplary method (700) for measuring tissue compression of an instrument (500) is described below. In step (702), method (700) may include compressing tissue between anvil (514) and deck surface (538). In step (704), method (700) may include firing instrument (500) to drive staples through the tissue. In step (706), method (700) may include measuring at least one of a compression force transmitted longitudinally through housing assembly (518) between a first housing and a second housing, and / or a tension force transmitted longitudinally through movable member (520) or anvil (514). As described above, the compression force transmitted longitudinally through housing assembly (518) while compressing tissue between anvil (514) and deck surface (538) or while firing instrument (500) may be measured using compression force sensor (504) disposed between the first housing and the second housing.

[0060] For example, the tissue compression force before firing can be measured using at least one compression force sensor (504) positioned at least at one or two or more of the positions between the deck member (540) and the body member (546) (i.e., the casing), between the body member and the outer sheath (544), between the outer sheath (544) and the casing (542) of the handle assembly (508), and between the casing (542) of the handle assembly (508) and the knob (516). The firing force can be measured using at least one compression force sensor (504) positioned between the casing (542) of the handle assembly (508) and the knob (516). As described above, the tension transmitted longitudinally through the movable member (520) while compressing the tissue between the anvil (514) and the deck surface (538) or the firing instrument (500) can be measured using a tension sensor (506) coupled to the movable member (520). For example, at least one tension sensor (506) can be coupled to the trocar operating rod (592), the trocar operating band assembly (594), and / or the trocar (522) to sense the tension of the trocar operating rod (592), the trocar operating band assembly (594), and / or the trocar (522).

[0061] In operation (708), method (700) may include determining at least one force based on the sensed compressive force obtained from compressive force sensor (504) and / or the sensed tensile force obtained from tensile force sensor (506). For example, the force by which instrument (500) compresses tissue disposed between deck surface (538) and anvil (514) prior to firing of the instrument (500), and / or the force by which the firing assembly of instrument (500) is actuated to fire instrument (500) onto the compressed tissue may be determined. Determining the tissue compression force may include correlating measurements of the compressive force and / or tensile force to the amount of tissue compression, using an algorithm, either before or during firing of instrument (500). The algorithm may be determined based on sensed data from other firings. The algorithm may include a transfer function that measures the actual compressive force using a calibrated system and then correlates the corresponding strain and compression from inside instrument (500) at various locations. For example, a look-up table may be used.

[0062] After determining the tissue compression force, in operation (710), method (700) may include communicating the sensed force to user interface mechanism (526) and / or communicating the sensed force to control system (524). Communicating the sensed force may include generating an indication that the tissue compression is within an acceptable range. For example, the indication may include one or more of an audible, tactile, or visual indication. Instrument (500) may provide feedback to the user or an algorithm to ensure optimal compression. Instrument (500) may also collect data after processing related to the implementation of instrument (500). For example, instrument (500) may record data related to tissue compression before and during firing. After determining the tissue compression, the method may also include uploading the tissue compression data to the cloud, as described above.

[0063] The instrument (500) can provide a plurality of advantages including measuring and determining the force of tissue compression before firing and / or the force to fire the instrument (10) using actual data from the instrument (10). In some variations, the instrument (500) can acquire real-time data, thereby enabling a user to act to improve staple formation and to acquire data from multiple instruments to confirm trends in desired changes. In some variations, the instrument (500) can use an algorithm to enable measurement of the actual tissue compression force and / or the force to fire without routing one or more wires through at least a portion of the shaft assembly (510) and the staple head assembly (512) prior to actual firing.

[0064] III. Exemplary Combinations The following examples relate to various non-exhaustive ways in which the teachings herein can be combined or applied. The following examples are not intended to limit the scope of any claims presented at any time in this application or in subsequent filings related to this application. No waiver of any rights is intended. The following examples are provided for illustrative purposes only. It is contemplated that the various teachings herein can be configured and applied in many other ways. Also, in some variations, it is contemplated that certain features mentioned in the following examples may be omitted. Accordingly, none of the aspects or features mentioned below should be considered important unless so expressly indicated later by the inventors or their successors in interest. If the claims presented in this application or in subsequent applications related to this application include additional features other than those mentioned below, those additional features should not be considered to have been added for any reason related to patentability.

Examples

[0065] A surgical instrument, comprising: (a) a housing assembly comprising: (i) a first housing, (ii) a second housing disposed adjacent to the first housing, and (iii) a deck surface including at least one annular array of staple openings; (b) a movable member at least partially disposed within the housing assembly; (c) an anvil selectively coupled to the movable member and configured to compress tissue between the anvil and the deck surface; and (d) a force sensing assembly comprising at least one of: (i) a compression force sensor disposed between the first housing and the second housing and 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, or (ii) a tension sensor coupled to the movable member or the anvil and configured to sense a tension 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).

Example

[0066] The surgical instrument according to Example 1, wherein the force sensing assembly comprises a compression force sensor disposed between the first housing and the second housing.

Example

[0067] The surgical instrument according to Example 1 or 2, wherein the compression force sensor includes a load cell.

Example

[0068] The first housing includes a body member configured to surround at least a portion of the movable member, the second housing includes a deck member, the deck member includes a deck surface, and the compression force sensor is configured to sense a compression force between the body member and the deck member while compressing tissue between the anvil and the deck surface. The surgical instrument according to any one of Examples 1 to 3.

Example

[0069] The surgical instrument according to Example 4, wherein the compression force sensor includes an annular ring surrounding at least a portion of the deck member while compressing tissue between the anvil and the deck surface.

Example

[0070] The first housing includes an outer sheath configured to surround at least a portion of the movable member, the second housing includes a body member configured to surround at least a portion of the movable member, the outer sheath is immovable relative to the body member, and the compression force sensor is configured to sense a compression force between the outer sheath and the body member while compressing tissue between the anvil and the deck surface. The surgical instrument according to any one or two or more of Examples 1 to 3.

Example

[0071] The first housing includes a handle assembly configured to be grasped by a user, the second housing includes an outer sheath configured to surround at least a portion of the movable member, the handle assembly is immovable relative to the outer sheath, and the compression force sensor is configured to sense a compression force between the handle assembly and the outer sheath while compressing tissue between the anvil and the deck surface. The surgical instrument according to any one or two or more of Examples 1 to 3.

Example

[0072] The first housing includes an actuator configured to translate a movable member, the second housing includes a handle assembly configured to be grasped by a user, and a compression force sensor is configured to sense a 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 a surgical instrument. The surgical instrument according to any one or two or more of Examples 1 to 3.

Example

[0073] The anvil includes a head and a shaft, the shaft is selectively coupled to the movable member and configured to compress tissue between the anvil and the deck surface, and a tension sensor is coupled to the movable member or the shaft of the anvil. The surgical instrument according to any one of Examples 1 to 8.

Example

[0074] The movable member includes a trocar actuation connection assembly, and a tension sensor is fixedly coupled to the trocar actuation connection assembly. The surgical instrument according to any one of Examples 1 to 9.

Example

[0075] The trocar actuation connection assembly includes an upper tension band and a lower tension band, and a tension sensor is fixedly coupled to the upper tension band. The surgical instrument according to Example 10.

Example

[0076] The tension sensor includes an in-line strain gauge. The surgical instrument according to any one of Examples 1 to 11.

Example

[0077] The movable member includes a trocar actuating band assembly and a trocar, the trocar being translationally coupled to the trocar actuating band assembly, and a tension sensor being disposed on the trocar actuating band assembly, on the trocar, or between the trocar actuating band assembly and the trocar, the surgical instrument according to any one or two or more of Examples 1 to 9 and 12.

Example

[0078] The surgical instrument according to any one of Examples 1 to 13, further comprising a control system, the force sensing assembly including a wire electrically connecting at least one of the tension sensor or the compression force sensor to the control system.

Example

[0079] The control system includes a user display mechanism unit, the control system being electrically coupled to the user display mechanism unit, the user display mechanism unit being configured to perform at least one of displaying the compression force or the tension, displaying whether the compression force or the tension is within an allowable range, recording the compression force or the tension, or uploading the compression force or the tension to the cloud, the surgical instrument according to Example 14.

Example

[0080] A surgical instrument, comprising: (a) a handle assembly including a casing; (b) a shaft assembly extending distally from the handle assembly, the shaft assembly including an outer sheath, a trocar operating rod, and a trocar operating connection assembly; (c) a stapling head assembly extending distally from the shaft assembly, the stapling head assembly including (i) a body member, (ii) a deck member including an annular array of staple apertures, and (iii) a trocar; (d) an anvil including a head and a shaft, the shaft being selectively coupled to the trocar and configured to compress tissue; (e) an actuator configured to translate the trocar relative to the handle assembly; and (f) a force sensing assembly including (i) a compression force sensor configured to sense a compression force transmitted longitudinally through the surgical instrument, the compression force sensor being positioned (1) between the deck member and the body member, (2) between the body member and the outer sheath, (3) between the outer sheath and the casing, or (4) between the casing and the actuator, or (ii) a tension sensor coupled to at least one of the trocar operating rod, the trocar operating connection assembly, the trocar, or the shaft of the anvil, the tension sensor being configured to sense a tension transmitted longitudinally through the shaft assembly, the trocar, or the anvil.

Example

[0081] A method of using a surgical instrument, the surgical instrument comprising a housing assembly having a first housing and a second housing disposed adjacent to each other and a deck surface including at least one annular array of staple apertures, 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) using, during at least one of (i) compressing the tissue between the anvil and the deck surface or firing the surgical instrument, a compression force sensor disposed between the first housing and the second housing to measure at least one of a compression force longitudinally transmitted through the housing assembly between the first housing and the second housing, or (ii) using a tension force sensor coupled to the movable member to measure at least one of a tension force longitudinally transmitted through the movable member during at least one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument; and (d) based on at least one of the compression force or the tension force, determining at least one of (i) the force with which the surgical instrument compresses tissue disposed between the deck surface and the anvil prior to firing of the surgical instrument, or (ii) the force with which the firing assembly of the surgical instrument is actuated to fire the surgical instrument onto the compressed tissue).

Example

[0082] The method according to Example 17, further comprising generating an indication that the tissue compression is within an acceptable range after determining the tissue compression.

Example

[0083] The method according to any one or more of Examples 17 to 18, wherein the measuring step further comprises correlating a measured value of the compression force or the tension force to an amount of tissue compression using an algorithm, before or during firing of the surgical instrument.

Example

[0084] The method according to any one or two or more of Examples 17 to 19, further comprising uploading at least one of the forces to a cloud after determining at least one of the forces.

[0085] IV. Others 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 two or more of the other teachings, expressions, embodiments, examples, etc. described herein. Therefore, the above teachings, expressions, embodiments, examples, etc. should not be considered in isolation from each other. Various suitable ways of combining the teachings of this specification will be readily apparent to those skilled in the art upon consideration of the teachings of this specification. Such modifications and variations are intended to be included within the scope of the claims.

[0086] The teachings disclosed herein may be combined with any of the teachings of U.S. Patent Application No. [Agent Docket No. END9260USNP1], filed on the same date as this application, entitled "Load Sensor for Circular Surgical Stapler", the disclosure of which is incorporated herein by reference.

[0087] Furthermore, any one or more of the teachings of this specification can be combined with any one or more of U.S. Patent Application No. 16 / 574,797, filed on September 18, 2019, titled "Method for Controlling Cutting Member Actuation for Powered Surgical Stapler"; U.S. Patent Application No. 16 / 574,281, filed on September 18, 2019, titled "Method for Controlling End Effector Closure for Powered Surgical Stapler"; and U.S. Patent Application No. 16 / 574,299, filed on September 18, 2019, titled "Anvil Retention and Release Features for Powered Circular Surgical Stapler". The disclosure content of each of these U.S. patent applications is incorporated herein by reference.

[0088] It should be understood that all or part of any patent, publication, or other disclosure referred to as being incorporated herein by reference is incorporated herein only to the extent that the incorporated content does not conflict with the existing definitions, opinions, or other disclosures described in this disclosure. In and of itself, and to the extent necessary, the disclosure clearly described herein shall prevail over any conflicting descriptions incorporated herein by reference. Any content, or portions thereof, that are referred to as being incorporated herein by reference but conflict with the current definitions, opinions, or other disclosures described herein shall be incorporated only to the extent that no conflict arises between the incorporated content and the current disclosure.

[0089] The above-described variant forms can be applied not only to conventional medical procedures and surgeries performed by medical professionals, but also to robot-assisted medical procedures and surgeries. As just one example, the various teachings herein can be readily incorporated into robotic surgical systems such as the DAVINCI (trademark) system by Intuitive Surgical, Inc. (Sunnyvale, California).

[0090] The above-described variant forms may be designed to be discarded after a single use, or they may be designed to be used multiple times. The variant forms can, in either or both cases, be readjusted for reuse after at least one use. The readjustment can include any combination of a disassembly step of the device, followed by a cleaning or replacement step of certain components, and a subsequent reassembly step. In particular, some variant forms of the device can be disassembled, and any number of specific parts or components of the device can be selectively replaced or removed in any combination. When cleaning and / or replacing certain components, some variant forms of the device can be reassembled for subsequent use in a readjustment facility or by the user immediately prior to the procedure. One skilled in the art will understand that various techniques for disassembly, cleaning / replacement, and reassembly can be utilized in the readjustment of the device. The use of such techniques, and the resulting readjusted device, are all within the scope of this application.

[0091] Merely by way of example, the deformations described in this specification may be sterilized before and / or after treatment. In one sterilization technique, the device is placed in a sealed and enclosed container such as a plastic or TYVEK bag. Next, the container and the device may be placed in a radiation field that can penetrate the container, such as gamma rays, X-rays, or high-energy electron beams. The radiation may kill bacteria on the device and within the container. Next, the sterilized device may be stored in a sterilized container for later use. The device can also be sterilized using any other technique well known in the art, including but not limited to beta or gamma rays, ethylene oxide, or steam.

[0092] Although various embodiments of the present invention have been shown and described, further adaptation of the methods and systems described herein can be achieved by those skilled in the art with appropriate modifications without departing from the scope of the present invention. Some of such possible modifications have been described, but other modifications will be apparent to those skilled in the art. For example, the above examples, embodiments, geometric shapes, materials, dimensions, ratios, steps, etc. are illustrative and not essential. Therefore, the scope of the present invention should be considered with respect to the following claims and it is understood that it is not limited to the details of the structures and operations shown and described in this specification and the drawings.

[0093] [Embodiment] (1) A surgical instrument, (a) A housing assembly, (i) A first housing, (ii) A second housing disposed adjacent to the first housing, and (iii) A housing assembly comprising a deck surface including 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. (d) A force sensing assembly, wherein the force sensing assembly is (i) A compression force sensor disposed between the first housing and the second housing, the compression force sensor 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 sensor coupled to the movable member or the anvil, the tension sensor configured to sense a tension 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, a force sensing assembly comprising at least one of the tension sensors, and a surgical instrument. (2) The surgical instrument according to embodiment 1, wherein the force sensing assembly comprises the compression force sensor disposed between the first housing and the second housing. (3) The surgical instrument according to embodiment 2, wherein the compression force sensor includes a load cell. (4) The first housing includes a body member configured to surround at least a portion of the movable member, the second housing includes a deck member, the deck member includes the deck surface, and the compression force sensor is configured to sense the compression force between the body member and the deck member while compressing the tissue between the anvil and the deck surface. The surgical instrument according to embodiment 2. (5) The surgical instrument according to embodiment 4, wherein the compression force sensor includes an annular ring surrounding at least a portion of the deck member while compressing the tissue between the anvil and the deck surface.

[0094] (6) The first housing includes an outer sheath configured to surround at least a portion of the movable member, the second housing includes a body member configured to surround at least a portion of the movable member, the outer sheath is stationary relative to the body member, and the compression force sensor is configured to sense the compression force between the outer sheath and the body member while compressing the tissue between the anvil and the deck surface. The surgical instrument according to embodiment 2. (7) The first housing includes a handle assembly configured to be grasped by a user, the second housing includes an outer sheath configured to surround at least a portion of the movable member, the handle assembly is stationary relative to the outer sheath, and the compression force sensor is configured to sense the compression force between the handle assembly and the outer sheath while compressing the tissue between the anvil and the deck surface. The surgical instrument according to embodiment 2. (8) The first housing includes an actuator configured to translate the movable member, the second housing includes a handle assembly configured to be grasped by a user, and the compression force sensor is configured to sense the compression force between the actuator and the handle assembly while at least one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument. The surgical instrument according to embodiment 2. (9) The anvil includes a head and a shaft, the shaft is selectively coupled to the movable member and configured to compress tissue between the anvil and the deck surface, and the tension sensor is coupled to the shaft of the movable member or the anvil. The surgical instrument according to embodiment 1. (10) The movable member includes a trocar actuation connection assembly, and the tension sensor is fixedly coupled to the trocar actuation connection assembly. The surgical instrument according to embodiment 9.

[0095] (11) The surgical instrument according to embodiment 10, wherein the trocar actuation connection assembly includes an upper tension band and a lower tension band, and the tension sensor is fixedly coupled to the upper tension band. (12) The surgical instrument according to embodiment 9, wherein the tension sensor includes an in-line strain gauge. (13) The surgical instrument according to embodiment 9, wherein the movable member includes a trocar actuation band assembly and a trocar, the trocar is translationally coupled to the trocar actuation band assembly, and the tension sensor is disposed on the trocar actuation band assembly, on the trocar, or between the trocar actuation band assembly and the trocar. (14) The surgical instrument according to embodiment 1, further comprising a control system, wherein the force sensing assembly includes a wire that electrically connects at least one of the tension sensor or the compression force sensor to the control system. (15) The surgical instrument according to embodiment 14, wherein the control system includes a user display mechanism, the control system is electrically coupled to the user display mechanism, and the user display mechanism is configured to perform at least one of displaying the compression force or the tension, displaying whether the compression force or the tension is within an acceptable range, recording the compression force or the tension, or uploading the compression force or the tension to the cloud.

[0096] (16) A surgical instrument, (a) a handle assembly, the handle assembly including a casing, the handle assembly, and (b) a shaft assembly extending distally from the handle assembly, the shaft assembly including an outer sheath, a trocar actuation rod, and a trocar actuation connection assembly, the shaft assembly, and (c) a stapling head assembly extending distally from the shaft assembly, the stapling head assembly including (i) A body member, (ii) A deck member including an annular array of staple openings, and (iii) A staple fastening head assembly comprising a trocar, and (d) An anvil including a head and a shaft, wherein the shaft is configured to be selectively coupled with the trocar to compress tissue, the anvil; and (e) An actuator configured to translate the trocar relative to the handle assembly; and (f) A force sensing assembly, wherein the force sensing assembly (i) A compression force sensor configured to sense a compression force transmitted longitudinally through the surgical instrument, wherein the compression force sensor (1) Is positioned between the deck member and the body member, (2) Is positioned between the body member and the outer sheath, (3) Is positioned between the outer sheath and the casing, or (4) Is positioned between the casing and the actuator, or a compression force sensor, or (ii) A tension sensor coupled to at least one of the trocar actuating rod, the trocar actuating connection assembly, the trocar, or the shaft of the anvil, the tension sensor being configured to sense a tension transmitted longitudinally through the shaft assembly, the trocar, or the anvil, a force sensing assembly comprising a tension sensor. A surgical instrument comprising. (17) A method of using a surgical instrument, the surgical instrument comprising a housing assembly comprising a first housing and a second housing disposed adjacent to each other and a deck surface including at least one annular array of staple openings, a movable member at least partially disposed within the housing assembly, an anvil configured to be selectively coupled to the movable member, and at least one of a compression force sensor or a tension 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) the following: (i) using a compression force sensor disposed between the first housing and the second housing, at least during one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument, a compression force longitudinally transmitted between the first housing and the second housing, or (ii) using a tension sensor coupled to the movable member, at least during one of compressing the tissue between the anvil and the deck surface or firing the surgical instrument, measuring at least one of the tensions longitudinally transmitted through the movable member; (d) based on at least one of the compression force or the tension: (i) prior to the time of firing the surgical instrument, a force for compressing the tissue disposed between the deck surface and the anvil by the surgical instrument, or (ii) determining at least one of the forces for firing the surgical instrument onto the compressed tissue when the firing assembly of the surgical instrument is actuated. (18) The method according to embodiment 17, further comprising generating an indication that the tissue compression is within an acceptable range after determining the tissue compression. (19) The method according to embodiment 17, wherein the measuring step further comprises correlating the measured value of the compression force or the tension to a tissue compression amount using an algorithm before or during firing of the surgical instrument. (20) The method according to embodiment 17, further comprising uploading at least one of the forces to the cloud after determining at least one of the forces.

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) including at least one annular array of staple apertures (556), (b) A movable member (520) at least partially disposed 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, (d) A force sensing assembly (502), the force sensing assembly comprising: (i) A compression force sensor (504) disposed between the first housing and the second housing, the compression force sensor configured to sense a pre-firing tissue compression force transmitted longitudinally through the first and second housings while the tissue between the anvil and the deck surface is being compressed, and a firing force transmitted longitudinally through the first and second housings during firing of the surgical instrument, or (ii) A tension sensor (506) coupled to the movable member, the tension sensor configured to sense the pre-firing tissue compression force transmitted longitudinally through the movable member while the tissue between the anvil and the deck surface is being compressed, and the firing force transmitted longitudinally through the movable member during firing of the surgical instrument, wherein the force sensing assembly (502) comprises at least one of the foregoing.

2. The surgical instrument according to 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 according to claim 2, wherein the compression force sensor includes a load cell.

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

5. The surgical instrument according to claim 4, wherein the compression force sensor includes an annular ring (548) surrounding at least a portion of the deck member while the tissue between the anvil and the deck surface is compressed.

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

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

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

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

10. The surgical instrument according to claim 9, wherein the movable member includes a trocar actuation connection assembly, and the tension sensor is fixedly coupled to the trocar actuation connection assembly.

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

12. The surgical instrument according to claim 9, wherein the tension sensor includes an in-line strain gauge (612).

13. The movable member includes a trocar actuating band assembly (594), a trocar actuating rod (592), and a trocar (522), the trocar being coupled to the trocar actuating band assembly for translation, and the tension sensor being disposed on the trocar actuating band assembly, on the trocar, on the trocar actuating rod, or between the trocar actuating band assembly and the trocar. The surgical instrument according to claim 9.

14. The surgical instrument according to claim 1, further comprising a control system (524), the force sensing assembly including a wire (528) that electrically connects at least one of the tension sensor or the compression force sensor to the control system.

15. The control system includes a user display mechanism, the control system being electrically coupled to the user display mechanism, and the user display mechanism being configured to perform at least one of displaying the compression force or the firing force, displaying whether the compression force or the firing force is within an acceptable range, recording the compression force or the firing force, or uploading the compression force or the firing force to the cloud. The surgical instrument according to claim 14.

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