A method for resetting an apparatus configured for stapling tissue, the apparatus comprising: (a) a stapling head assembly, wherein the stapling head assembly comprises: (i) an annularly arranged array of staples, and (ii) a knife with an annular cutting edge that is configured to cut tissue; (b) a shaft assembly coupled to the stapling head assembly, wherein the shaft assembly comprises a drive bracket; and (c) a body coupled to the shaft assembly, wherein the body comprises: (i) a motor, (ii) a cam member configured to rotate in response to activation of the motor, wherein the cam member is rotatable in a first direction from a home position to a fired position, (iii) a cam follower, wherein the cam member is configured to interact with the cam follower, the cam follower is pivotably coupled with the drive bracket, wherein pivoting of the cam follower, due to rotation of the cam member in the first direction from the home position to the fired position, drives the drive bracket to actuate the stapling head assembly to thereby drive the staples and the knife through tissue, and (iv) a casing, wherein the cam member is positioned within the casing; wherein the method comprises: (a) providing an apparatus, in a testing or quality control setting, or after use in a procedure, including the cam member in the fired position; characterised in that the method further comprises: (b) removing at least a portion of the casing; and (c) rotating the cam member in a second direction from the fired position to the home position, and the cam member comprises a concavely defined surface region, wherein the concavely defined surface region of the cam member is configured to bear against the cam follower during a first portion of the rotation of the cam member from the fired position to the home position, such that rotating the cam member from the fired position to the home position causes the cam follower and drive bracket to move in directions which are opposite to the directions in which they move due to rotation of the cam member from the home position to the fired position, such that the stapling head assembly is returned to a non-actuated state. (a) a stapling head assembly, wherein the stapling head assembly comprises: (i) an annularly arranged array of staples, and (ii) a knife with an annular cutting edge that is configured to cut tissue; (i) an annularly arranged array of staples, and (ii) a knife with an annular cutting edge that is configured to cut tissue; (b) a shaft assembly coupled to the stapling head assembly, wherein the shaft assembly comprises a drive bracket; and (c) a body coupled to the shaft assembly, wherein the body comprises: (i) a motor, (ii) a cam member configured to rotate in response to activation of the motor, wherein the cam member is rotatable in a first direction from a home position to a fired position, (iii) a cam follower, wherein the cam member is configured to interact with the cam follower, the cam follower is pivotably coupled with the drive bracket, wherein pivoting of the cam follower, due to rotation of the cam member in the first direction from the home position to the fired position, drives the drive bracket to actuate the stapling head assembly to thereby drive the staples and the knife through tissue, and (iv) a casing, wherein the cam member is positioned within the casing; (i) a motor, (ii) a cam member configured to rotate in response to activation of the motor, wherein the cam member is rotatable in a first direction from a home position to a fired position, (iii) a cam follower, wherein the cam member is configured to interact with the cam follower, the cam follower is pivotably coupled with the drive bracket, wherein pivoting of the cam follower, due to rotation of the cam member in the first direction from the home position to the fired position, drives the drive bracket to actuate the stapling head assembly to thereby drive the staples and the knife through tissue, and (iv) a casing, wherein the cam member is positioned within the casing; wherein the method comprises: (a) providing an apparatus, in a testing or quality control setting, or after use in a procedure, including the cam member in the fired position; (a) providing an apparatus, in a testing or quality control setting, or after use in a procedure, including the cam member in the fired position; characterised in that the method further comprises: (b) removing at least a portion of the casing; and (c) rotating the cam member in a second direction from the fired position to the home position, and (b) removing at least a portion of the casing; and (c) rotating the cam member in a second direction from the fired position to the home position, and the cam member comprises a concavely defined surface region, wherein the concavely defined surface region of the cam member is configured to bear against the cam follower during a first portion of the rotation of the cam member from the fired position to the home position, such that rotating the cam member from the fired position to the home position causes the cam follower and drive bracket to move in directions which are opposite to the directions in which they move due to rotation of the cam member from the home position to the fired position, such that the stapling head assembly is returned to a non-actuated state.