Powered surgical circular stapler with removable cartridge and pivoting anvil

A surgical instrument, comprising:

• (a) a stapling assembly, including:
• (i) a cartridge housing surrounding and extending along a longitudinal axis from a distal end portion to a proximal end portion thereof,
• (ii) a staple deck positioned within the distal end portion of the cartridge housing, wherein the staple deck includes an annular array of staple pockets positioned about the longitudinal axis, wherein the staple pockets are configured to house a plurality of staples,
• (iii) a staple driver housed within the cartridge housing and configured to translate distally from a proximal driver position toward a distal driver position to thereby drive the staples distally from the annular array of staple pockets for forming the staples in a tissue of a patient,
• (iv) a cylindraceous knife housed within the cartridge housing and surrounding the longitudinal axis, wherein the cylindraceous knife is configured to translate distally from a proximal knife position toward a distal knife position for cutting the tissue of the patient,
• (v) a trocar extending distally along the longitudinal axis, wherein the trocar is configured to translate longitudinally between a proximal trocar position and a distal trocar position,
• (vi) a first rotatable drive member configured to drive translation of at least one of the staple driver, the cylindraceous knife, or the trocar in response to a first rotational input,
• (vii) a second rotatable drive member at configured to drive translation of a remaining of the at least one of the staple driver, the cylindraceous knife, or the trocar in response to a second rotational input wherein the first and second rotatable drive members are arranged coaxially, and
• (viii) an anvil configured to releasably couple to the trocar, including:
• (A) an anvil shaft having a proximal shaft end portion and a distal shaft end portion, wherein the proximal shaft end portion is configured to releasably couple with the trocar, and
• (B) an anvil head having a proximal face and a linking connector projecting proximally from the proximal face, wherein the proximal face has a plurality of staple forming pockets configured to respectively receive the plurality of staples thereagainst thereby forming each of the plurality of staples for substantially sealing a severed tissue, wherein the distal shaft end portion is pivotally connected to the linking connector, wherein the anvil head is configured to pivot about a pivot axis relative to the anvil shaft, and wherein the pivot axis is transverse to the longitudinal axis;
• and
• (b) a proximal assembly having a distal end portion configured to removably couple with the stapling assembly to thereby operatively couple the first and second rotatable drive members with at least one motor configured to drive rotation of the first and second rotatable drive members.

A method of operating a surgical instrument, wherein the surgical instrument has a proximal assembly, a stapling assembly, and an anvil, wherein the stapling assembly includes a cartridge housing, a staple deck, a plurality of staples, a staple driver, a cylindraceous knife, a trocar, a rotary drive element, and a drive member engaged with the rotary drive element, wherein the anvil includes an anvil shaft and an anvil head, wherein the anvil shaft has a proximal shaft end portion and a distal shaft end portion, wherein the proximal shaft end portion is releasably coupled with the trocar, wherein the anvil head is pivotally connected to the distal shaft end portion, wherein the anvil head has a proximal face with a plurality of staple forming pockets configured to respectively receive the plurality of staples thereagainst thereby forming each of the plurality of staples for substantially sealing a severed tissue, the method comprising:

• (a) removably coupling a proximal end of the stapling assembly with a distal end of the proximal assembly such that a first locking feature of the stapling assembly lockingly engages a second locking feature of the proximal assembly and such that the rotary drive element engages a rotary drive shaft of the proximal assembly;
• (b) pivoting the anvil head relative to the anvil shaft to orient the anvil head at a non-perpendicular orientation relative to the anvil shaft;
• (c) securing the anvil shaft to the trocar;
• (d) pivoting the anvil head relative to the anvil shaft to orient the anvil head at a perpendicular orientation relative to the anvil shaft;
• (e) providing rotation of the rotary drive shaft such that the rotary drive element rotates therewith and thereby drives the drive member distally, wherein in response to distal translation of the drive member the staple driver advances distally to fire the staples through the staple deck;
• and
• (f) separating the proximal end of the stapling assembly from the distal end of the proximal assembly.