WO2016179737A1

WO2016179737A1 - Anvil assembly and method of assembling components of anvil assembly

Info

Publication number: WO2016179737A1
Application number: PCT/CN2015/078509
Authority: WO
Inventors: Hui Zhan; Xinsheng Liu
Original assignee: Covidien Lp; Covidien (China) Medical Devices Technology Co., Ltd.
Priority date: 2015-05-08
Filing date: 2015-05-08
Publication date: 2016-11-17

Abstract

A method of assembling components of an anvil assembly (20) and an anvil assembly (20) formed using the method, the method includes positioning an anvil plate (42) within an outer annular recess (58) of an anvil head (40); positioning a fixture (70) of a metal working machine adjacent an annular lip (66) of the anvil head (40), the annular lip (66) being positioned adjacent the outer annular recess (58) of the anvil head (40); rotating the anvil head (40) in relation to the fixture (70) about the longitudinal axis of the anvil head (40); and moving the fixture (70)inwardly towards a longitudinal axis of the anvil head (40) to deform the annular lip (66) of the anvil head (40) and form an annular lip portion (66a) that extends over an outer surface ( 42b) of the anvil plate (42) to secure the anvil plate (42) within the outer annular recess (58). The anvil assembly (20) formed using the method provides a smoother external surface to facilitate atraumatic insertion of the anvil assembly (20) through a body lumen.

Description

ANVIL ASSEMBLY AND METHOD OF ASSEMBLING COMPONENTS OF THE ANVIL ASSEMBLY

BACKGROUND

1. Technical Field

The present disclosure relates to circular stapling devices for performing intra-luminal medical procedures. More specifically, the present disclosure relates to an anvil assembly of a circular stapling device and a method of assembling components of the anvil head of the anvil assembly to facilitate atraumatic insertion of the anvil assembly into a body lumen.

2. Background of Related Art

Circular stapling devices for performing surgical procedures within a body lumen typically include a tool assembly including an annular cartridge assembly supporting a plurality of staples and an anvil assembly including an annular anvil plate, an anvil head, and an anvil shaft. The anvil head is supported on a distal end of the anvil shaft and defines an annular recess configured to receive the anvil plate. After the anvil plate is received within the recess of the anvil head, the anvil plate is secured within the recess using a machining process such as swaging.

Circular surgical stapling devices are used to perform a variety of surgical procedures within a body lumen including anastomoses procedures as well as procedures for the treatment of hemorrhoids, e.g., hemorrhoidectomies, mucosectomies, and prolapsectomies. During a hemorrhoid treatment procedure, the anvil assembly of the surgical stapling device is inserted into a body lumen to a location adjacent tissue to be treated. During insertion, the anvil head moves along the inner wall of the body lumen. As such, it is desirable to provide an anvil head that can be atraumatically received within a lumen.

SUMMARY

The present disclosure is directed to a method of assembling components of an anvil assembly. In embodiments, the method includes positioning an anvil plate within an outer annular recess of an anvil head； and positioning a fixture of a metal working machine adjacent an annular lip of the anvil head, wherein the annular lip is positioned adjacent the outer annular recess of the anvil head. The method further includes rotating the anvil head in relation to the fixture about the longitudinal axis of the anvil head； and moving the fixture inwardly towards a longitudinal axis of the anvil head to deform the annular lip of the anvil head and form an annular lip portion that extends over an outer surface of the anvil plate to secure the anvil plate within the outer annular recess.

In embodiments, the step of rotating the anvil head in relation to the fixture includes securing the anvil head to a lathe to rotate the anvil head in relation to the fixture.

In some embodiments, the step of moving the fixture to deform the annular lip of the anvil head includes moving the fixture in a direction perpendicular to the longitudinal axis of the anvil head.

In certain embodiments, the step of positioning a fixture of a metal working machine adjacent an annular lip of the anvil head includes positioning the fixture in a close relationship with the anvil plate such that moving the fixture inwardly towards the longitudinal axis of the anvil head to deform the annular lip of the anvil head to form an annular lip portion forms an annular lip portion having a thickness in the range of . 0005 and . 01 inch, or in other embodiments, in the range of . 001 and . 003 inch.

In embodiments, the method further includes positioning a cut ring within an inner annular recess of the anvil head.

In some embodiments, the method further includes securing an atraumatic anvil cap to a distal end of the anvil body.

In embodiments, the method further includes securing an anvil shaft to the anvil head.

In some embodiments, the step of securing an anvil shaft to the anvil head includes positioning a proximal end of the anvil shaft within a central hub of the anvil head.

In another aspect of the disclosure, an anvil assembly includes an anvil head defining an outer annular recess and including an annular lip positioned about the outer annular recess, and an anvil plate having an outer surface positioned within the outer annular recess. The annular lip includes a lip portion that is deformed transversely over the outer surface of the anvil plate. The lip portion extends in a direction perpendicular to the longitudinal axis of the anvil head.

In embodiments, the lip portion has a thickness in the range of , 0005 and . 01 inch. In other embodiments, the lip portion has a thickness in the range of . 001 and . 003 inch.

In embodiments, the anvil assembly further includes an anvil shaft having a proximal end secured to the anvil head.

In some embodiments, the anvil head includes a central hub portion and the proximal end of the anvil shaft is received within the central hub portion.

In certain embodiments, the anvil head defines an inner annular recess and the anvil assembly further includes a cut ring positioned within the inner annular recess of the anvil head.

In embodiments, an atraumatic anvil cap is secured to a distal end of the anvil body.

Brief Description of the Drawings

Various embodiments of the presently disclosed anvil assembly of a circular stapling device are described herein with reference to the drawings, wherein:

FIG. 1 is a side, perspective view of one embodiment of the presently disclosed anvil assembly secured to a circular stapling device with the anvil assembly in an open position；

FIG. 2 is a side, perspective view of the distal end of the circular stapling device shown in FIG. 1 with the anvil assembly separated from a body of the circular stapling device；

FIG. 3 is a side, perspective, exploded view of the anvil assembly of the circular stapling device shown in FIG. 1；

FIG. 4 is a side, cross-sectional view of the anvil assembly of the circular stapling device shown in FIG. 1 with an anvil plate secured to the anvil head of the anvil assembly；

FIG. 5 is an enlarged view of the indicated area of detail shown in FIG. 4；

FIG. 6 is a side cross-sectional view of a portion of the anvil plate and anvil head of the anvil assembly show in FIG. 4 with the anvil plate positioned within an outer annular recess of the anvil head prior to securement of the anvil plate within the outer annular recess；

FIG. 7 is a side view schematically illustrating a rolling member of a metal working machine as the roller moves transversely in relation to the anvil head to deform an annular lip of the anvil head over the anvil plate to secure the anvil plate to the anvil head；

FIG. 7A is an enlarged view of the indicated area of detail shown in FIG. 7； and

FIG. 8 is a perspective view from the proximal end of the distal end of the anvil assembly including the anvil plate and anvil head with the anvil plate secured to the anvil head.

Detailed Description of Embodiments

Embodiments of the presently disclosed anvil assembly and method of assembling components of the anvil assembly of a circular stapling device will now be described in detail with reference to the drawings wherein like reference numerals designate identical or corresponding elements in each of the several views. In this description, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel. In addition, the term “proximal” is used generally to refer to the portion of the apparatus that is closer to a clinician， while the term “distal” is used generally to refer to the portion of the apparatus that is farther from the clinician.

The present disclosure is directed to an anvil assembly and a method of assembling components of the anvil assembly of a circular surgical stapling device to facilitate atraumatic insertion of the anvil assembly through a body lumen. The method includes positioning an anvil plate within an outer annular recess of an anvil head and then deforming an annular lip of the anvil head inwardly over an outer surface of the anvil plate to secure the anvil plate within the outer annular recess of the anvil head. In embodiments, the annular lip of the anvil head is deformed inwardly to define a thin lip portion that extends over the anvil plate in a direction substantially perpendicular to a longitudinal axis of the anvil head to provide a substantially smooth external surface adjacent the outer end of the anvil plate and anvil head.

FIG. 1 illustrates a circular surgical stapling device 10 including a handle assembly 12, a body portion 14, and a tool assembly 16 including a cartridge assembly 18 and an anvil assembly 20. The body portion 14 has a proximal end 14a supported on the handle assembly 12 and a distal end 14b that supports the cartridge assembly 18 of the tool assembly 16. The cartridge assembly 18 includes a housing or shell 22 and an annular cartridge 24 that supports a plurality of staples (not shown) . In embodiments, the staples are supported in one or more annular rows 26 within the cartridge 24.

The handle assembly 12 includes a stationary handle 28, a firing trigger 30 pivotally supported in relation to the stationary handle 28, and a rotatable knob 32 supported on the proximal end of the handle assembly 12. The rotatable knob 32 is operatively connected to an anvil retainer 35, via an approximation mechanism (not shown) , that is movably positioned through the cartridge assembly 18 and supports the anvil assembly 20 for movement relative to the cartridge 24. For a more detailed description of the approximation mechanism and other internal components of the stapling device 10 including the handle assembly 12, body portion 14 and tool assembly 16, see U.S. Patent Nos. 8,424,535 and 8,360,295 that are incorporated herein in their entirety by reference.

Referring to FIGS. 2 and 3, the anvil assembly 20 includes an anvil shaft 34 and an anvil head assembly 36 including an anvil cap 38, an anvil head 40, an anvil plate 42 and a cut ring 44. The anvil cap 38 has an atraumatic bulbous tip 46 and is supported on a distal end of the anvil head 40 to facilitate atraumatic entry of the anvil assembly 20 into a body lumen as described below. In embodiments, the anvil cap 38 includes a plurality of spring fingers 50 that are configured to engage the anvil head 40 to secure the anvil cap 38 onto the distal end of the anvil head 40.

The anvil head 40 has a distal face that defines a central hub 54 that is configured to receive a proximal end 34a of the anvil shaft 34, an inner annular recess 56 and an outer annular recess 58. The cut ring 44 defines a central opening 44a that is dimensioned to receive the central hub 54 such that the cut ring 44 is positioned within the inner annular recess 56 between the central hub 54 and the outer annular recess 58. The cut ring 44 is positioned within the inner annular recess 56 of the anvil head 40 at a location to engage a knife blade 60 (FIG. 1) of the stapling device 10 that is movably supported within the cartridge assembly 18.

Referring also to FIGS. 4 and 5, the outer annular recess 58 is surrounded by an annular shoulder 64 formed on the anvil head 40 that supports an outer end 42a of the anvil plate 42. An annular lip 66 is positioned radially outwardly of the annular shoulder 64 and is deformable inwardly over an outer surface 42b of the anvil plate 42, as described in further detail below, to secure the anvil plate 42 to the anvil head 40.

The anvil shaft 34 includes a proximal end defining a trocar 34b and a distal end 34a received within the central hub 54. The distal portion of the anvil shaft 34 includes a plurality of annular grooves 48. The grooves 48 are provided to facilitate attachment of a purse-string suture to the anvil shaft 34. By attaching the purse-string suture to a selected one of the annular grooves 48 of the anvil shaft 34, the amount of tissue drawn into the housing 22 of the cartridge assembly 18 when the anvil assembly 20 is approximated towards the cartridge 24 can be controlled.

The anvil shaft 34 also includes a plurality of splines 49 and a locking surface 49a. The splines 49 are positioned to be received within grooves (not shown) formed within the cartridge assembly 18 to rotatably align the anvil assembly 20 in relation to the cartridge assembly 18 during approximation of the anvil assembly 20 and the cartridge assembly 18. The locking surface 49a is configured to releasably engage the anvil retainer 35 (FIG. 2) . For a more detailed description of the anvil assembly 20 and how the anvil assembly 20 is engaged with the anvil retainer 35, see the ‘535 Patent.

Referring to FIGS. 6 and 7, the method of assembling the components of the anvil assembly includes positioning the anvil plate 42 within the outer annular recess 58 of the anvil head 40 such that the outer end 42a of the anvil plate 42 is supported on the annular shoulder 64 of the anvil head 40. Next, a fixture 70, e.g., a roller (FIGS. 7-7A) , of a metal working machine (not shown) is positioned adjacent the annular lip 66 of the anvil head 40. Thereafter, the anvil head 40 is rotated in relation to the fixture 70 as indicated by arrow “X” in FIG. 7. As the anvil head 40 is rotated in relation to the fixture 70, the fixture 70 is moved radially inwardly towards a longitudinal axis of the anvil head 40 in the direction indicated by arrow “Y” in FIG. 7 to deform the annular lip 66 to form a transverse lip portion 66a (FIG. 5) that extends over the outer surface 42b of the anvil plate 42. In embodiments, the fixture 70 is positioned in relation to the anvil head 40 such that the transverse lip portion 66a annular lip 66 positioned over the outer end 42a of the anvil plate 42 has a thickness in the range of . 0005 and . 01 inch, or in other embodiments, in the range of . 001 and . 003 inch. In embodiments, the lip portion 66a of the annular lip 66 of the anvil head 40 extends in a direction substantially perpendicular to the longitudinal axis of the anvil shaft 34. In addition, the outer surface 42b of the anvil plate 42 defines a plane that is substantially perpendicular to the longitudinal axis of the anvil shaft 34. Thus, the lip portion 42b lays flat atop the outer surface 42b of the anvil plate 42 (FIG. 5) .

In embodiments, the fixture 70 is provided with a rounded engagement surface 70a (FIG. 7A) that is positioned to engage and move over the annular lip 66 of the anvil head 40. In addition, the outer surface of the annular lip 66 has a curved outer surface 66a. In some embodiments, the anvil head 40 is supported in a lathe (not shown) and the fixture 70 is rotatably fixed on one side of the anvil head 40 but movable transversely in relation to the anvil head 40 to deform the annular lip 66 inwardly over the outer end 42a of the anvil plate 42.

In embodiments, the anvil plate 42 is a stamped part and the anvil head 40 is a machined part.

The method described above produces an anvil head assembly 36 that has a smooth external surface adjacent the interface between the anvil head and the anvil plate that is less likely to snag tissue during insertion and/or removal of the anvil assembly 20 from a body lumen. More specifically, the securement of the anvil plate 42 within the annular recess 58 of the anvil head 40 with an annular lip portion 66a of reduced thickness that is positioned flat atop the anvil plate 42 provides a smoother external surface to the anvil head 36 adjacent the interconnection between anvil plate 42 and the anvil head 40. As such, the anvil head assembly 36 is less likely to snag tissue as the anvil assembly 20 is moved through a body lumen.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the present disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims.

Claims

A method of assembling components of an anvil assembly, the method comprising:

positioning an anvil plate within an outer annular recess of an anvil head；

positioning a fixture of a metal working machine adjacent an annular lip of the anvil head, the annular lip being positioned adjacent the outer annular recess of the anvil head；

rotating the anvil head in relation to the fixture about the longitudinal axis of the anvil head； and

moving the fixture inwardly towards a longitudinal axis of the anvil head to deform the annular lip of the anvil head and form an annular lip portion that extends over an outer surface of the anvil plate to secure the anvil plate within the outer annular recess.
The method according to claim 1, wherein rotating the anvil head in relation to the fixture includes securing the anvil head to a lathe to rotate the anvil head in relation to the fixture.
The method according to claim 1, wherein moving the fixture to deform the annular lip of the anvil head includes moving the fixture in a direction perpendicular to the longitudinal axis of the anvil head.
The method according to claim 1, wherein positioning a fixture of a metal working machine adjacent an annular lip of the anvil head includes positioning the fixture in a close relationship with the anvil plate such that moving the fixture inwardly towards the longitudinal axis of the anvil head to deform the annular lip of the anvil head to form an annular lip portion forms an annular lip portion having a thickness in the range of . 0005 and . 01 inch.
The method according to claim 1, wherein the annular lip portion has a thickness in the range of . 001 and . 003 inch.
The method according to claim 1, further including positioning a cut ring within an inner annular recess of the anvil head.
The method according to claim 1, further including securing an atraumatic anvil cap to a distal end of the anvil body.
The method according to claim 1, further including securing an anvil shaft to the anvil head.
The method according to claim 7, wherein securing an anvil shaft to the anvil head includes positioning a proximal end of the anvil shaft within a central hub of the anvil head.
An anvil assembly comprising:

an anvil head defining an outer annular recess and an annular lip positioned about the outer annular recess； and

an anvil plate positioned within the outer annular recess, the anvil plate having an outer surface；

wherein the annular lip includes a lip portion that is deformed transversely over the outer surface of the anvil plate, the lip portion extending in a direction perpendicular to the longitudinal axis of the anvil head.
The an anvil assembly according to claim 10, wherein the lip portion has a thickness in the range of . 0005 and . 01 inch.
The anvil assembly according to claim 11, wherein the lip portion has a thickness in the range of . 001 and . 003 inch
The anvil assembly according to claim 10, further including an anvil shaft having a proximal end secured to the anvil head.
The anvil assembly according to claim 13, wherein the anvil head includes a central hub portion and the proximal end of the anvil shaft is received within the central hub portion.
The anvil assembly according to claim 11, wherein the anvil head defines an inner annular recess and the anvil assembly further includes a cut ring positioned within the inner annular recess of the anvil head.
The anvil assembly according to claim 10, further including an atraumatic anvil cap secured to a distal end of the anvil body.