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EP-4294285-B1 - SURGICAL STAPLING DEVICE INCLUDING A HYDRAULIC STAPLE FORMATION MECHANISM

EP4294285B1EP 4294285 B1EP4294285 B1EP 4294285B1EP-4294285-B1

Inventors

  • NICHOLAS, DAVID A.

Dates

Publication Date
20260506
Application Date
20220208

Claims (15)

  1. A shell assembly (18) comprising: a shell housing (156) defining a cavity (174); a plurality of staples (206); a staple cartridge (202) supported on the shell housing, the staple cartridge defining slots (204) that receive the plurality of staples; a pusher assembly (212) positioned within the cavity of the shell housing and including a plurality of pushers (212a) arranged in an annular configuration to eject the plurality of staples from the staple cartridge; and a hydraulic piston (500) configured to engage the pusher assembly to impart axial displacement to the pusher assembly and form a fluid tight seal against the shell housing, wherein supply of a fluid into the cavity of the shell housing advances the hydraulic piston, which, in turn, advances the pusher assembly to eject the plurality of staples from the staple cartridge, wherein the shell housing includes an annular guide (201) in the cavity, the annular guide defining a bore (159a) therethrough ; characterised in that the shell housing includes a clamp gear (168) rotatably supported therein.
  2. The shell assembly according to claim 1, further comprising an annular knife (310) supported on the hydraulic piston for concomitant axial displacement therewith.
  3. The shell assembly according to claim 1 or 2, wherein the hydraulic piston defines inner and outer circumferential grooves (506, 507) that receive respective inner and outer O-rings (512, 514).
  4. The shell assembly according to claim 3, wherein the inner O-ring is configured to engage the annular guide of the shell housing.
  5. The shell assembly according to claim 1, wherein the clamp gear is aligned with the annular guide of the shell housing.
  6. The shell assembly according to claim 5, wherein a proximal portion of the shell housing includes an inner lip (157) defining a cutout to rotatably support a clamp input gear (120) such that the clamp input gear operatively engages the clamp gear.
  7. The shell assembly according to claim 6, wherein the inner lip defines a bore in communication with the cavity of the shell housing.
  8. A surgical stapling device comprising: an adapter assembly (14) including: a flexible outer tube (32); a first drive assembly (36) extending through the flexible outer tube, the first drive assembly including a flexible approximation link (84) and an anvil retainer (88) secured to the flexible approximation link; a second drive assembly (40) extending through the flexible outer tube, the second drive assembly including a flexible drive shaft (108) and an input gear (120) secured to the flexible drive shaft; and a third drive assembly (50) including: a hydraulic cylinder (550) disposed in the flexible outer tube; and a first piston (520) movable within the hydraulic cylinder; and a tool assembly (16) secured to a distal portion of the flexible outer tube, the tool assembly including: an anvil assembly (20) including an anvil head (130) and an anvil shaft (132) secured to the anvil head; and a shell assembly as claimed in claim 1, wherein the clamp gear is supported within the housing of the shell assembly, the clamp gear operatively engaged with the input gear of the second drive assembly; wherein activation of the first drive assembly through a first clamping stage retracts the flexible articulation link to move the anvil retainer proximally to move the anvil assembly from an open position to a partially clamped position in which the anvil retainer is operatively engaged with the clamp gear, activation of the second drive assembly through a second clamping stage moves the anvil retainer farther proximally to move the anvil assembly from the partially clamped position to a fully clamped position, and activation of the third drive assembly advances the first piston to direct the fluid into the housing of the shell assembly to advance the second piston, thereby advancing the pusher assembly.
  9. The surgical stapling device according to claim 8, wherein the anvil shaft has a threaded outer portion in registration with the clamp gear when the anvil assembly is in the partially retracted position.
  10. The surgical stapling device according to claim 9, wherein the anvil shaft is releasably coupled to the anvil retainer.
  11. The surgical stapling device according to claim 8, further including a handle assembly (12), the adapter assembly having a proximal portion coupled to the handle assembly.
  12. The surgical stapling device according to claim 8, wherein the adapter assembly includes a flexible fluid supply tube (560) interconnecting the hydraulic cylinder and the housing of the shell assembly such that the hydraulic cylinder and the housing of the shell assembly are in fluid communication.
  13. A surgical stapling device comprising: an adapter assembly (14) including: a flexible outer tube (32); a first drive assembly (36) extending through the flexible outer tube, the first drive assembly including a flexible approximation link (84) and an anvil retainer (88) secured to a distal portion of the flexible approximation link; a second drive assembly (40) extending through the flexible outer tube, the second drive assembly including a flexible drive shaft (108) and an input gear (120) secured to a distal portion of the flexible drive shaft; and a third drive assembly (50) including a hydraulic cylinder (550), a first piston (520), and a flexible tube (560) in fluid communication with the hydraulic cylinder; and a tool assembly (16) secured to a distal portion of the flexible outer tube, the tool assembly including: an anvil assembly (20) including an anvil head (130) and an anvil shaft (132) secured to the anvil head; and a shell assembly as claimed in claim 1, wherein the cavity is in fluid communication with the flexible tube of the third drive assembly; the clamp gear is engaged with the input gear of the second drive assembly, wherein activation of the first drive assembly through a first clamping stage retracts the flexible approximation link to move the anvil retainer proximally to move the anvil assembly from an open position to a partially clamped position, in which, the anvil shaft is operatively engaged with the clamp gear, wherein activation of the second drive assembly through a second clamping stage moves the anvil retainer farther proximally to move the anvil assembly from the partially clamped position to a fully clamped position, and wherein activation of the third drive assembly advances the first piston in the hydraulic cylinder to direct a fluid into the cavity of the shell housing through the flexible tube, thereby advancing the pusher assembly.
  14. The stapling device according to claim 13, wherein the tool assembly further includes an annular knife (310) supported on the hydraulic piston.
  15. The stapling device according to claim 14, wherein the clamp gear has a threaded bore configured to threadably engage a threaded outer portion of the anvil shaft.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit of and priority to U.S. Provisional Patent Application Serial No. 63/149,845, filed on February 16, 2021, the entire disclosure of which is referenced herein. BACKGROUND Technical Field The disclosure relates to surgical instruments and, more particularly, to an endoscopic stapling device with a flexible shaft that supports an end effector. Background of Related Art Surgical stapling devices for performing surgical procedures endoscopically are well known and are commonly used to reduce patient trauma and shorten patient recovery times. Typically, an endoscopic stapling device includes a handle assembly, a rigid elongate body that extends distally from the handle assembly, and an end effector including a tool assembly that is supported on a distal portion of the elongate body. The handle assembly is coupled to the end effector by drive mechanisms that extend through the elongate body and allow a clinician to control operation of the end effector remotely via the handle assembly. Surgical stapling devices for endoscopic use are available in a variety of configurations including linear and circular. Circular stapling devices are commonly used to perform anastomoses after resections of the large bowel, i.e., colectomies. In a large percentage of colectomy procedures, the portion of the colon that must be resected is in the ascending colon or the transverse colon which cannot be easily accessed by a circular stapling device having a rigid shaft. As such, these procedures are typically performed during an open colectomy procedure which result in increased patient trauma and recovery time. US 5 395 030 discloses a surgical device for stapling and fastening body tissues, which comprises a staple-applying section containing a plurality of staples, a staple pusher incorporated in the staple-applying section, for applying the staples, an anvil section for deforming the staples, thereby to staple the body tissues together, an operation section for operating the staple pusher and the anvil section, an observation window located near the anvil section, and an ocular section for displaying images supplied from the observation window. A continuing need exists in the medical arts for a stapling device having a flexible shaft for accessing a surgical site. SUMMARY The invention is defined by the appended claims. In accordance with the disclosure, a shell assembly includes a shell housing defining a cavity, a plurality of staples, a staple cartridge supported on the shell housing, a pusher assembly positioned within the cavity of the shell housing, and a hydraulic piston configured to engage the pusher assembly to impart axial displacement to the pusher assembly and form a fluid tight seal against the shell housing. The staple cartridge defines slots that receive the plurality of staples. The pusher assembly includes a plurality of pushers arranged in an annular configuration to eject the plurality of staples from the staple cartridge. Supply of a fluid into the cavity of the shell housing advances the hydraulic piston, which, in turn, advances the pusher assembly to eject the plurality of staples from the staple cartridge. In an aspect, the shell housing may include an annular guide in the cavity that defines a bore therethrough. In another aspect, the shell assembly may further include an annular knife supported on the hydraulic piston for concomitant axial displacement therewith. In yet another aspect, the hydraulic piston may define inner and outer circumferential grooves configured to receive respective inner and outer O-rings. In still yet another aspect, the inner O-ring may be configured to engage the annular guide of the shell housing. In still yet another aspect, the shell housing may include a clamp gear rotatably supported therein. In still yet another aspect, the clamp gear may be aligned with the annular guide of the shell housing. In an aspect, a proximal portion of the shell housing may include an inner lip defining a cutout to rotatably support a clamp input gear such that the clamp input gear operatively engages the clamp gear. In another aspect, the inner lip may define a bore in communication with the cavity of the shell housing. In accordance with another aspect of the disclosure, a surgical stapling device includes an adapter assembly and a tool assembly. The adapter assembly includes a flexible outer tube, a first drive assembly extending through the flexible outer tube, a second drive assembly extending through the flexible outer tube, and a third drive assembly. The first drive assembly includes a flexible approximation link and an anvil retainer secured to the flexible approximation link. The second drive assembly includes a flexible drive shaft and an input gear secured to the flexible drive shaft. The third drive assembly includes a hydraulic cylinder disposed in the flexible outer tube and a first piston movable within the