Handheld electromechanical surgical system

Abstract

A surgical instrument includes an annular reload, and an anvil assembly configured to move relative to the annular reload between an open position and a preset closed position in which the anvil assembly and the annular reload define a preset gap distance therebetween. A processor of the surgical instrument is configured to determine a difference between the preset gap distance and an actual gap distance between the anvil assembly and the annular reload, and to adjust a staple stroke and a cut stroke by the determined difference between the preset gap distance and the actual gap distance.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 051,026, filed July 13, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to surgical devices. More specifically, this disclosure relates to handheld electromechanical surgical systems for performing surgical procedures. Background Technology

[0004] One type of surgical device is a circular clamping, cutting, and stapler. This device can be used in surgical procedures or similar procedures to reattach a previously transverse rectal segment. Conventional circular clamping, cutting, and staplers comprise a pistol- or linear gripper structure with an elongated shaft extending from it and a staple cartridge supported at the distal end of the elongated shaft. In this example, the surgeon inserts the anvil assembly of the circular stapler into the patient's rectum and manipulates the anvil assembly upwards along the patient's colon toward the transverse rectal segment. The surgeon can also insert the remaining portion of the circular stapler (including the cartridge assembly) through an incision toward the transverse rectal segment. The anvil and cartridge assembly approach each other, and staples are fired from the cartridge assembly toward the anvil assembly to form staples in the tissue for end-to-end anastomosis, and a circular blade is actuated to cored a portion of the clamped tissue. After achieving the end-to-end anastomosis, the circular stapler is removed from the surgical site.

[0005] Several surgical device manufacturers have developed product lines with dedicated powered drive systems for operating and / or manipulating surgical devices. In many cases, surgical devices include reusable powered handle assemblies, as well as disposable staple cartridge assemblies, end effectors, etc., which are selectively connected to the powered handle assembly before use and then disconnected from the staple cartridge assembly or end effector after use for disposal or, in some cases, sterilization for reuse.

[0006] Over the past few decades, the use of battery-powered electro- and internally mechanical surgical staplers, including those with intelligent battery power, has increased dramatically. The advanced technologies and information within these intelligent battery-powered staplers provide the ability to collect clinical data and drive design improvements to ultimately improve patient outcomes. Therefore, there is a need for improved battery-powered electro- and internally mechanical surgical staplers capable of assessing conditions affecting staple formation in order to develop smarter stapler algorithms. Summary of the Invention

[0007] According to an aspect of the disclosure, a surgical instrument is provided and includes a handle assembly, an adapter assembly configured to selectively couple to the handle assembly, and an end effector. The handle assembly includes a memory having instructions stored therein, and a processor configured to execute the instructions. The adapter assembly includes a trocar, and the end effector includes an anvil assembly configured to couple to the trocar, and an annular reload selectively coupled to a distal portion of the adapter assembly. The anvil assembly is configured to move relative to the annular reload between an open position and a preset closed position in which the anvil assembly and the annular reload define a preset gap distance therebetween. The processor is configured to determine a difference between the preset gap distance and an actual gap distance between the anvil assembly and the annular reload using the instructions stored in the memory. The processor is further configured to adjust a staple stroke and a cut stroke by the determined difference between the preset gap distance and the actual gap distance.

[0008] In some aspects, the annular reload can include a plurality of staples, and the staple stroke can be a linear distance traveled by the staples during ejection of the staples from the annular reload.

[0009] The annular reload can further include an annular knife, and the cut stroke can be a linear distance traveled by the annular knife during a cutting sequence of the annular knife.

[0010] In some aspects, the memory can have stored therein preset staple strokes and preset cut strokes each corresponding to the preset gap distance. The adjusted staple stroke can be the preset staple stroke minus the determined difference between the preset gap distance and the actual gap distance, and the adjusted cut stroke can be the preset cut stroke minus the difference between the preset gap distance and the actual gap distance.

[0011] In some aspects, the processor can be further configured to determine whether the actual gap distance is less than the preset gap distance.

[0012] In some aspects, the processor can be further configured to determine whether a force exerted on the trocar is less than a threshold force when the end effector is in the closed position. The processor can be further configured to retract the anvil assembly toward the annular reload in response to determining that the force exerted on the trocar is less than the threshold force.

[0013] In some aspects, the processor can be further configured to set the gap distance upon determining that the force exerted on the trocar is at the threshold force.

[0014] According to another aspect of the disclosure, a method of using a surgical instrument is provided and includes retracting an anvil assembly toward an annular reload from an open position to a closed position in which a gap distance defined between the anvil assembly and the annular reload is at a preset gap distance, further retracting the anvil assembly toward the annular reload from the preset gap distance to an adjusted gap distance, and adjusting a staple stroke and a cut stroke by a difference between the preset gap distance and the adjusted gap distance.

[0015] In some aspects, the staple stroke can be a linear distance traveled by the staples during ejection from the annular reload and the cut stroke can be a linear distance traveled by the annular knife during a cutting sequence of the annular knife.

[0016] In some aspects, the adjusted staple stroke can be equal to the preset staple stroke minus the difference between the preset gap distance and the adjusted gap distance and the adjusted cut stroke can be equal to the preset cut stroke minus the difference between the preset gap distance and the adjusted gap distance.

[0017] In some aspects, the method can further include ejecting the staples from the annular reload by the adjusted staple stroke and advancing the annular knife from the annular reload by the adjusted cut stroke.

[0018] In some aspects, the method can further include determining whether a force exerted on the anvil assembly by tissue is less than a threshold force when the anvil assembly is in the closed position. The anvil assembly can be further retracted in response to determining that the force exerted on the trocar is less than the threshold force.

[0019] In some aspects, the method can further include setting the gap distance upon determining that the force exerted on the anvil assembly is at the threshold force.

[0020] In another aspect of the disclosure, a surgical instrument is provided and includes an adapter assembly including a trocar, an end effector, and a handle assembly configured to be coupled to the adapter assembly. The end effector includes an annular reload configured to be selectively coupled to a distal portion of the adapter assembly and an anvil assembly. The annular reload includes a plurality of staples and an annular knife. The anvil assembly is configured to be coupled to the trocar and move relative to the annular reload between an open position and a preset closed position in which the anvil assembly and the annular reload define a preset gap distance therebetween. The handle assembly includes a processor configured to determine a difference between the preset gap distance and an actual gap distance between the anvil assembly and the annular reload and adjust a staple stroke and a cut stroke by the determined difference between the preset gap distance and the actual gap distance.

[0021] In some aspects, the handle assembly may include a memory that stores a preset nail stroke and a preset cutting stroke, each corresponding to a preset gap distance.

[0022] In some respects, the adjusted pin stroke can be the preset pin stroke minus the difference between a predetermined preset gap distance and the actual gap distance. The adjusted cutting stroke can be the preset cutting stroke minus the difference between a preset gap distance and the actual gap distance. Attached Figure Description

[0023] Embodiments of this disclosure are described herein with reference to the accompanying drawings, in which:

[0024] Figure 1 This is a perspective view of a handheld surgical instrument including a handle assembly, an adapter assembly, and an end effector according to an embodiment of the present disclosure;

[0025] Figure 2 yes Figure 1 A schematic diagram of the handle assembly, adapter assembly, and end effector;

[0026] Figure 3 It is a side perspective view of the adapter assembly and the end effector attached to the adapter assembly (e.g., the annular reload and anvil assembly).

[0027] Figure 4 This is a perspective view of the adapter assembly, partially shown in dashed lines, without end effectors (e.g., the ring reload and anvil assembly);

[0028] Figure 5A It is used for implementation Figure 1 A flowchart of the method for the stapled function of surgical instruments; and

[0029] Figure 5B It is used for implementation Figure 1 A flowchart of the method for the cutting function of surgical instruments. Detailed Implementation

[0030] The presently disclosed surgical apparatus and embodiments of adapter assemblies for the surgical apparatus and / or handle assembly are described in detail with reference to the accompanying drawings, in which similar reference numerals denote the same or corresponding elements in each of the figures. As used herein, the term "distal" refers to the portion of the surgical instrument or its components that is further away from the user, while the term "proximal" refers to the portion of the surgical instrument or its components that is closer to the user.

[0031] An intelligent surgical instrument, such as a handheld surgical instrument, includes a handle assembly, an adapter assembly coupled to the handle assembly, and an end effector coupled to the adapter assembly. A stapler allows full independent control of three functions: clamping, stapling, and cutting. This allows certain portions of the stapler to adapt if the tissue presents a non-ideal situation. For example, in the case of handling very thin tissue, it can be advantageous to move the anvil of the end effector closer to the distal end of the adapter assembly in order to confirm the anvil attachment to the adapter assembly.

[0032] The present disclosure relates to software that will allow and compensate for anvil movement in the case when the stapler has been fully clamped and the load on the anvil is less than a target threshold. In this case, the stapler can move the anvil towards the adapter assembly (e.g., proximally) until the target threshold load is detected. With this in mind, the staple stroke and the cut stroke are adjusted to the corresponding delta anvil positions. This maintains consistent firing regardless of clamping distance. The adjusted staple stroke maintains consistent staple crimping even if the anvil is not in place; and the adjusted cut stroke ensures the correct cut distance regardless of anvil position.

[0033] Figure 1 A surgical instrument, such as a circular stapler 1, is shown that includes a handle assembly 100 configured for selective connection with an adapter assembly 200, and, in turn, the adapter assembly 200 is configured for selective connection with an end effector 300 that includes a reload 400 (of a plurality of reloads) and an anvil assembly 500. The end effector 300 is configured to produce a surgical effect on tissue of a patient. The handle assembly 100 is a powered electromechanical handle assembly that includes a powered handle 101 Figure 2 ) and a housing shell 10 configured to selectively receive and encase the powered handle 101. The housing shell 10 includes a distal half-section 10a and a proximal half-section 10b pivotably connected to the distal half-section 10a. When engaged, the distal half-section 10a and the proximal half-section 10b define a shell cavity therebetween in which the powered handle 101 is selectively located.

[0034] The distal half-section 10a and the proximal half-section 10b of the housing shell 10 are divided along a plane that is transverse to a longitudinal axis “X” of the adapter assembly 200. The distal half-section 10a of the housing shell 10 defines a connection portion 20 configured to accept a corresponding drive coupling assembly 210 Figure 3 ) of the adapter assembly 200. The distal half-section 10a of the housing shell 10 supports a distally facing toggle control button 30. The toggle control button 30 is actuatable in left, right, up, and down directions upon application of a respective force thereto or upon application of a press force thereto.

[0035] Reference is made to Figure 1 and 2 The power handle 101 includes a controller circuit board 142, a rechargeable battery 144 configured to power any of the electrical components of the handle assembly 100, and a motor 152 coupled to the battery 144. In embodiments, the motor 152 can be coupled to any suitable power source configured to provide electrical energy to the motor 152, such as an AC / DC transformer. The battery 144 and motor 152 are coupled to a motor controller circuit board 142 having a motor controller 143 that controls operation of the motor 152, including the flow of electrical energy from the battery 144 to the motor 152. A main controller 147 is provided that controls the power handle 101.

[0036] The motor controller 143 includes a plurality of sensors 408a, 408b,... 408n configured to measure operating conditions of the motor 152 and battery 144. The sensors 408a-n can include voltage sensors, current sensors, temperature sensors, telemetry sensors, optical sensors, and combinations thereof. The sensors 408a-408n can measure voltage, current, and other electrical properties of the electrical energy supplied by the battery 144. The sensors 408a-408n can also measure angular velocity (e.g., rotational speed) (revolutions per minute (RPM)), torque, temperature, current draw, and other operating characteristics of the motor 152. Angular velocity can be determined by measuring rotation of the motor 152 or a drive shaft (not shown) coupled thereto and rotatable by the motor 152. Various linear sensors disposed in or proximate to the shaft can also be used to determine the position of various axially movable drive shafts, or the position is extrapolated from the RPM measurement. In embodiments, torque can be calculated based on the regulated current draw of the motor 152 at a constant RPM. In further embodiments, the motor controller 143 and / or the main controller 147 can measure time and process the above values over time, including integration and / or differentiation, to determine, for example, rates of change of measured values. The main controller 147 is also configured to determine the distance traveled by the various components of the circular adapter assembly 200 and / or the end effector 300 by counting the revolutions of the motor 152.

[0037] The motor controller 143 is coupled to the main controller 147, which includes a plurality of inputs and outputs for interfacing with the motor controller 143. In particular, the main controller 147 receives measured sensor signals from the motor controller 143 regarding operating conditions of the motor 152 and battery 144, and in turn outputs control signals to the motor controller 143 to control operation of the motor 152 based on the sensor readings and specific algorithmic instructions. The main controller 147 is also configured to accept a plurality of user inputs from a user interface (e.g., switches, buttons, touchscreens, etc. coupled to the main controller 147).

[0038] The main controller 147 is also coupled to a memory 141. The memory 141 can include volatile (e.g., RAM) and non-volatile storage configured to store data including software instructions for operating the power handle 101. The main controller 147 is also coupled to strain gauges (not explicitly shown) of the circular adapter assembly 200 using a wired or wireless connection and is configured to receive strain measurements from the strain gauges used during operation of the power handle 101.

[0039] In addition to the first motor 152, the power handle 101 includes a second motor (not explicitly shown) and a third motor (not explicitly shown), each electrically connected to the controller circuit board 142 and the battery 144. Each motor 152 includes a respective motor shaft (not explicitly shown) extending therefrom. Rotation of the respective motor 152 to rotate the motor shaft can drive a shaft and / or gear assembly of the adapter assembly 200 in order to perform various operations of the handle assembly 100. In particular, the motors 152 of the power handle 101 are configured to drive a shaft and / or gear assembly of the adapter assembly 200 in order to selectively extend / retract a trocar component 274 of a trocar assembly 270 of the adapter assembly 200 Figure 4 ); open / close an end effector 300 (when the anvil assembly 500 is connected to the trocar component 274 of the trocar assembly 270), fire an annular staple array of the reload 400, and fire an annular knife (not explicitly shown) of the reload 400.

[0040] Turning now to Figures 3-4 , the adapter assembly 200 includes an outer knob housing 202 and an outer tube 206 extending from a distal end of the knob housing 202. The knob housing 202 and the outer tube 206 are configured and dimensioned to house components of the adapter assembly 200. The adapter assembly 200 is configured to convert rotation of a coupling shaft (not explicitly shown) of the handle assembly 100 to axial translation that can be used to operate a trocar assembly 270, an anvil assembly 500, and / or a staple driver assembly (not explicitly shown) or a knife assembly (not explicitly shown) of the reload 400 of the adapter assembly 200.

[0041] The adapter assembly 200 also includes a trocar assembly 270 removably supported in the distal end of the outer tube 206. The trocar assembly 270 includes a trocar component 274 and a drive screw 276 operably received within the trocar component 274 for axially moving the trocar component 274 relative to the outer tube 206. A distal end 274b of the trocar component 274 is configured to selectively engage the anvil assembly 500 such that axial movement of the trocar component 274 via rotation of the drive screw 276 results in concomitant axial movement of the anvil assembly 500.

[0042] The force during actuation of the trocar assembly 274 or closure of the end effector 300 (e.g., retraction of the anvil assembly 500 relative to the reload 400) can be measured by the strain gauge to monitor and control firing of the staples from the reload 400; monitor the force during firing and formation of the staples as the staples are ejected from the reload 400; optimize staple formation (e.g., staple crimp height) for different pathologies of tissue as the staples are ejected from the reload 400; and monitor and control firing of the annular knife of the reload 400.

[0043] The strain gauge of the adapter assembly 200 measures and monitors retraction of the trocar assembly 274. During closure of the end effector 300, if and when the anvil assembly 500 contacts tissue, an obstacle, the tissue contact surface of the annular reload 400, or the like, a reaction force in the generally distal direction is imparted on the anvil assembly 500. This distally directed reaction force is transmitted from the anvil assembly 500 to the strain gauge. The strain gauge then transmits a signal to the main controller circuit board 142 of the powered handle 101 of the handle assembly 100. A graphic is then displayed on the display screen (not shown) of the handle assembly 100 to provide the user with real-time information about the firing status of the handle assembly 100.

[0044] Further details regarding the construction and operation of the circular stapler and its components can be found in International Application No. PCT / US2019 / 040440, filed July 3, 2019, the entirety of which is incorporated herein by reference.

[0045] In operation, the anvil assembly 500 (which has been positioned by the surgeon) is attached to the trocar assembly 274 and the user initiates the clamping process on the tissue interposed between the circular reload 400 and the anvil assembly 500 by pressing on the bottom of the toggle control button 30. During clamping, the anvil assembly 500 is retracted towards the circular reload 400 until reaching the fully clamped position, i.e., the position of the anvil assembly 500 such that the tissue is fully clamped between the anvil assembly 500 and the reload 400. The pre-set fully clamped position varies for each of the different types of reloads (e.g., the distance is about 29 mm for a 25 mm reload). Upon clamping, the strain gauge continuously provides the main controller 147 with measurements regarding the force exerted on the trocar assembly 274 as the trocar assembly moves the anvil assembly 500 to compress the tissue between the anvil assembly 500 and the annular reload 400.

[0046] At the full clamped position (e.g., a preset gap distance defined between the anvil assembly 500 and the annular reload 400), the main controller 147 uses the measurements taken by the strain gauges to determine whether the measured force is equal to or less than the target threshold load. If the main controller 147 determines that the measured force is less than the target threshold load, it indicates that the clamped tissue is very thin, and thus the gap distance between the anvil assembly 500 and the reload 400 will need to be reduced below the preset gap distance of the full clamped position. Accordingly, the anvil assembly 500 is further retracted beyond the full clamped position until the target threshold load is detected, with the anvil assembly 500 in the over-clamped state. Since the gap distance between the anvil assembly 500 and the reload 400 is less than the preprogrammed gap distance of the end effector 300, the total amount of distal movement of the staples and the annular knife (e.g., staple stroke and cut stroke, respectively) should also be adjusted during the corresponding stapling and cutting sequences.

[0047] Referring to a flowchart illustrating a cutting sequence Figure 5A The software stored in the memory 141 instructs the main controller 147 to determine whether the anvil assembly 500 is in the over-clamped state described above. If the main controller 147 determines that the anvil assembly 500 has been retracted to the over-clamped state (e.g., due to the thickness of the tissue being less than the preprogrammed gap distance), the main controller 147 calculates a staple adjustment. The staple adjustment can include a reduction in the distance of the staple stroke compared to the preset staple stroke. The preset staple stroke can be adjusted (e.g., reduced) by the difference between the gap distance in the over-clamped state and the gap distance in the full clamped state.

[0048] To begin the stapling sequence, the user presses the toggle control button 30, which causes the staples to be ejected from the reload 400 into the anvil assembly 500 to deform the staples through the tissue. The staples are ejected from the reload 400 to the tissue by the adjusted staple stroke. If the measured strain is within the minimum and maximum staple force limits, the main controller 147 determines that the stapling process is successfully completed. The progress of the staple firing is illustrated by an animation of the anastomosis, the launch progress bar, and the staple formation.

[0049] Referring to a flowchart illustrating a cutting sequence Figure 5BThe software stored in the memory 141 includes instructions that, when executed by the host controller 147, allow the host controller 147 to determine whether the anvil assembly 500 is in an over-clamp condition. If the host controller 147 determines that the anvil assembly 510 has approached an over-clamp condition (e.g., due to a tissue thickness that is less than a preprogrammed gap distance), the host controller 147 calculates a cut adjustment, e.g., a reduction in the cut stroke as compared to a pre-set cut stroke. The pre-set cut stroke is adjusted (e.g., reduced) by the difference between the gap distance in the over-clamp condition and the gap distance in the fully clamped condition. Thus, upon actuation of the cutting function, the knife is translated from the reload 400 by the adjusted cut stroke.

[0050] It should be understood that various modifications can be made to the presently disclosed adapter assembly embodiments. Therefore, the above description should not be construed as limiting, but merely as exemplification of the embodiments. Other modifications within the scope and spirit of the disclosure will occur to those skilled in the art.

[0051] In one or more examples, the described techniques can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media can include non-transitory computer-readable media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

[0052] Instructions can be executed by one or more processors, such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term "processor," as used herein can refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. Moreover, the techniques can be embodied within one or more circuits or logic elements.

Claims

1. A surgical instrument, comprising: a handle assembly including a memory storing instructions therein and a processor configured to execute the instructions; an adapter assembly configured to selectively couple to the handle assembly, the adapter assembly including a trocar; and an end effector including: an annular reload configured to selectively couple to a distal portion of the adapter assembly; and an anvil assembly configured to couple to the trocar and move relative to the annular reload between an open position and a preset closed position in which the anvil assembly and the annular reload define a preset gap distance therebetween, wherein the processor, using the instructions stored in the memory, is configured to: determine a difference between the preset gap distance and an actual gap distance between the anvil assembly and the annular reload; and adjust a staple stroke and a cut stroke by the determined difference between the preset gap distance and the actual gap distance.

2. The surgical instrument of claim 1, wherein the annular reload includes a plurality of staples and the staple stroke is a linear distance traveled by the staples during ejection of the staples from the annular reload.

3. The surgical instrument of claim 2, wherein the annular reload further includes an annular knife and the cut stroke is a linear distance traveled by the annular knife during a cutting sequence of the annular knife.

4. The surgical instrument of claim 3, wherein the memory has stored therein a preset staple stroke and a preset cut stroke each corresponding to the preset gap distance, and wherein the adjusted staple stroke is the preset staple stroke less the determined difference between the preset gap distance and the actual gap distance, and the adjusted cut stroke is the preset cut stroke less the difference between the preset gap distance and the actual gap distance.

5. The surgical instrument of claim 1, wherein the processor is further configured to determine whether the actual gap distance is less than the preset gap distance.

6. The surgical instrument of claim 1, wherein the processor is further configured to: determine whether a force exerted on the trocar is less than a threshold force when the end effector is in the closed position; and retract the anvil assembly toward the annular reload in response to determining that the force exerted on the trocar is less than the threshold force.

7. The surgical instrument of claim 6, wherein the processor is further configured to set the gap distance upon determining that the force exerted on the trocar is at the threshold force.

8. A computer readable medium storing instructions that, when executed by a processor, cause the processor to perform a method of using a surgical instrument, the method comprising: retracting an anvil assembly toward an annular reload from an open position to a closed position in which a gap distance defined between the anvil assembly and the annular reload is at a preset gap distance; ​ further retracting the anvil assembly toward the annular reload from the preset gap distance to an adjusted gap distance; and adjusting a staple stroke and a cut stroke by a difference between the preset gap distance and the adjusted gap distance.

9. The computer readable medium of claim 8, wherein the staple stroke is a linear distance traveled by the staples during ejection from the annular reload and the cut stroke is a linear distance traveled by the annular knife during a cutting sequence of the annular knife.

10. The computer readable medium of claim 9, wherein the adjusted staple stroke is equal to a preset staple stroke minus the difference between the preset gap distance and the adjusted gap distance and the adjusted cut stroke is equal to a preset cut stroke minus the difference between the preset gap distance and the adjusted gap distance.

11. The computer readable medium of claim 10, further comprising: ejecting the staples from the annular reload by the adjusted staple stroke; and advancing the annular knife from the annular reload by the adjusted cut stroke.

12. The computer readable medium of claim 8, further comprising determining whether a force exerted on the anvil assembly by tissue is less than a threshold force when the anvil assembly is in the closed position, wherein the anvil assembly is further retracted in response to determining that the force exerted on the anvil assembly is less than the threshold force.

13. The computer readable medium of claim 12, further comprising setting the gap distance upon determining that the force exerted on the anvil assembly is at the threshold force.

14. A surgical instrument, comprising: an adapter assembly including a trocar; and an end effector including: an annular reload configured to be selectively coupled to a distal portion of the adapter assembly, the annular reload including a plurality of staples and an annular knife; and an anvil assembly configured to be coupled to the trocar and move relative to the annular reload between an open position and a preset closed position, wherein the anvil assembly and the annular reload define a preset gap distance therebetween; and a handle assembly configured to be coupled to the adapter assembly, the handle assembly including a processor configured to: determine a difference between the preset gap distance and an actual gap distance between the anvil assembly and the annular reload; and adjust a staple stroke and a cut stroke by the determined difference between the preset gap distance and the actual gap distance.

15. The surgical instrument of claim 14, wherein the staple stroke is a linear distance traveled by the staples during ejection from the annular reload and the cut stroke is a linear distance traveled by the annular knife during a cutting sequence of the annular knife.

16. The surgical instrument of claim 15, wherein the handle assembly further includes a memory storing a preset staple stroke and a preset cut stroke each corresponding to the preset gap distance.

17. The surgical instrument of claim 16, wherein the adjusted staple stroke is the preset staple stroke minus a determined difference between the preset gap distance and the actual gap distance, and the adjusted cut stroke is the preset cut stroke minus the difference between the preset gap distance and the actual gap distance.

18. The surgical instrument of claim 14, wherein the processor is further configured to determine whether the actual gap distance is less than the preset gap distance.

19. The surgical instrument of claim 14, wherein the processor is further configured to: determine whether a force exerted on the trocar is less than a threshold force when the end effector is in the preset closed position; and retract the anvil assembly toward the annular reload in response to determining that the force exerted on the trocar is less than the threshold force.

20. The surgical instrument of claim 19, wherein the processor is further configured to set the gap distance upon determining that the force exerted on the trocar is at the threshold force. ​ ​

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