U.S. patent application number 15/156761 was filed with the patent office on 2016-09-08 for in-situ loaded stapler.
The applicant listed for this patent is Covidien LP. Invention is credited to Ernest Aranyi, Stanislaw Kostrzewski, Paul Scirica.
Application Number | 20160256167 15/156761 |
Document ID | / |
Family ID | 49447355 |
Filed Date | 2016-09-08 |
United States Patent
Application |
20160256167 |
Kind Code |
A1 |
Kostrzewski; Stanislaw ; et
al. |
September 8, 2016 |
IN-SITU LOADED STAPLER
Abstract
In one aspect of the present disclosure a surgical stapling
apparatus is disclosed including a cartridge assembly. The
cartridge assembly includes at least one cartridge having a first
half and a second half, a first row of retention slots disposed in
the first half, a second row of retention slots disposed in the
second half, a third row of retention slots being alternately
disposed in the first half and the second half of the at least one
cartridge between the first and second rows of staple receiving
slots, a plurality of fasteners disposed in the retention slots of
the first, second and third rows, and a plurality of pushers
disposed in each of the first and second halves of the
cartridge.
Inventors: |
Kostrzewski; Stanislaw;
(Newtown, CT) ; Aranyi; Ernest; (Easton, CT)
; Scirica; Paul; (Huntington, CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Covidien LP |
Mansfield |
MA |
US |
|
|
Family ID: |
49447355 |
Appl. No.: |
15/156761 |
Filed: |
May 17, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13652569 |
Oct 16, 2012 |
9364217 |
|
|
15156761 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 17/07207 20130101;
A61B 2017/07271 20130101; A61B 2017/07242 20130101; A61B 17/068
20130101; A61B 17/105 20130101; A61B 2017/2931 20130101; A61B
2017/00473 20130101; A61B 2017/07235 20130101; A61B 2017/07278
20130101; A61B 2017/00398 20130101; A61B 17/072 20130101 |
International
Class: |
A61B 17/10 20060101
A61B017/10; A61B 17/072 20060101 A61B017/072 |
Claims
1. (canceled)
2. A staple cartridge assembly comprising: a first staple cartridge
including: a first cartridge portion including a first row of
retention slots and a first tissue contacting surface; a second
cartridge portion including a second row of retention slots and a
second tissue contacting surface, the second cartridge portion
releasably attachable to the first cartridge portion; and a third
row of retention slots being alternately disposed in the first
cartridge portion and the second cartridge portion of the first
staple cartridge, the third row of retention slots disposed between
the first and second rows of retention slots and defining a third
tissue contacting surface, wherein at least two of the first,
second, and third tissue contacting surfaces exist in different
planes.
3. The staple cartridge assembly of claim 2, wherein each of the
first, second, and third tissue contacting surfaces exist in
different planes.
4. The staple cartridge assembly of claim 2, wherein the first
staple cartridge further includes: a plurality of fasteners
disposed in the retention slots of the first, second, and third
rows of retention slots.
5. The staple cartridge assembly of claim 4, wherein the first
staple cartridge further includes: a plurality of pushers disposed
in each of the first and second cartridge portions, each pusher of
the plurality of pushers being disposed in operative association
with at least one of the retention slots of the first staple
cartridge and being configured to eject a respective fastener from
at least one retention slot of the first, second, or third rows of
retention slots.
6. The staple cartridge assembly of claim 2, further comprising a
second staple cartridge configured to couple to the first staple
cartridge at a distal end portion thereof.
7. The staple cartridge assembly of claim 6, wherein the second
staple cartridge includes: a third cartridge portion including a
fourth row of retention slots and a fourth tissue contacting
surface; a fourth cartridge portion including a fifth row of
retention slots and a fifth tissue contacting surface, the fourth
cartridge portion releasably attachable to the third cartridge
portion; and a sixth row of retention slots being alternately
disposed in the third cartridge portion and the fourth cartridge
portion of the second staple cartridge, the sixth row of retention
slots disposed between the fourth and fifth rows of retention slots
and defining a sixth tissue contacting surface, wherein at least
two of the fourth, fifth, and sixth tissue contacting surfaces
exist in different planes.
8. The staple cartridge assembly of claim 7, wherein the first and
second staple cartridges define a longitudinal slot
therebetween.
9. The staple cartridge assembly of claim 8, wherein the
longitudinal slot is configured to facilitate passage of a knife
blade therethrough.
10. The staple cartridge assembly of claim 2, further including a
cartridge support channel configured to receive the first and
second cartridge portions of the first staple cartridge therein and
maintain engagement therebetween.
11. The staple cartridge assembly of claim 2, further including a
staple magazine disposed in operative association with each
retention slot of the first staple cartridge, each staple magazine
including a plurality of fasteners therein and configured to supply
a fastener of the plurality of fasteners to the corresponding
retention slot.
12. The staple cartridge assembly of claim 11, wherein the
plurality of fasteners associated with the first row of retention
slots has a first size, the plurality of fasteners associated with
the second row of retention slots has a second size, and the
plurality of fasteners associated with the third row of retention
slots has a third size, the first, second, and third sizes being
different.
13. The staple cartridge assembly of claim 12, wherein the first
size is greater than the third size and the third size is greater
than the second size.
14. A method of assembling an end effector, comprising: forming a
first staple cartridge by coupling a first cartridge portion to a
second cartridge portion, the first staple cartridge includes a
first row of retention slots disposed in the first cartridge
portion, a second row of retention slots disposed in the second
cartridge portion, and a third row of retention slots being
alternately disposed in the first cartridge portion and the second
cartridge portion, the third row of retention slots disposed
between the first and second rows of retention slots; forming a
second staple cartridge by coupling a third cartridge portion to a
fourth cartridge portion, the second staple cartridge includes a
fourth row of retention slots disposed in the third cartridge
portion, a fifth row of retention slots disposed in the fourth
cartridge portion, and a sixth row of retention slots being
alternately disposed in the third cartridge portion and the fourth
cartridge portion, the sixth row of retention slots disposed
between the fourth and fifth rows of retention slots; and coupling
the first staple cartridge and the second staple cartridge such
that the first and second staple cartridges are configured for
insertion into an elongated support channel.
15. The method of claim 14, wherein coupling the first and second
cartridge portions further includes coupling flanges and channels
defined on the first cartridge portions with corresponding flanges
and channels defined on the second cartridge portion, the channels
of the first and second cartridge portions being configured to
receive the corresponding flanges of the first and second cartridge
portions, respectively.
16. The method of claim 14, further including inserting the first
staple cartridge into a first cartridge support channel such that
engagement between the first and second cartridge portions is
maintained.
17. The method of claim 14, wherein coupling the first and second
staple cartridges further includes coupling a distal portion of
each respective first and second staple cartridge.
18. The method of claim 14, further including inserting first and
second staple cartridges into an elongated support channel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation application of
U.S. patent application Ser. No. 13/652,569, filed Oct. 16, 2012,
the entire contents of which is incorporated herein by
reference.
BACKGROUND
[0002] 1. Technical Field
[0003] This application relates to a surgical stapling apparatus,
and more particularly, to a cartridge assembly including multiple
cartridge halves and a magazine for reloading the surgical stapling
apparatus in-situ.
[0004] 2. Background of Related Art
[0005] Surgical devices wherein tissue is first grasped or clamped
between opposing jaw structure and then joined by surgical
fasteners are well known in the art. In some instruments a knife is
provided to cut the tissue which has been joined by the fasteners.
The fasteners are typically in the form of surgical staples but two
part polymeric fasteners can also be utilized.
[0006] Instruments for this purpose can include two elongated
members which are respectively used to capture or clamp tissue.
Typically, one of the members carries a staple cartridge which
houses a plurality of staples arranged in at least two lateral rows
while the other member has an anvil that defines a surface for
forming the staple legs as the staples are driven from the staple
cartridge. Generally, the stapling operation is effected by a cam
bar, a drive sled or other similar mechanism, that travels
longitudinally through the staple cartridge and acts upon the
staple pushers to sequentially eject the staples from the staple
cartridge. A knife can travel between the staple rows to
longitudinally cut and/or open the stapled tissue between the rows
of staples. Some staplers apply a double row of staples on each
side of the incision by providing a disposable loading unit in
which a cam member moves through an elongate guide path between two
sets of staggered staple carrying grooves. Staple drive members are
located within the grooves and are positioned in such a manner so
as to be contacted by the longitudinally moving cam member to
effect ejection of the staples from the staple cartridge of the
disposable loading unit.
[0007] In endoscopic or laparoscopic procedures, surgery is
performed through a small incision or through a narrow cannula
inserted through small entrance wounds in the skin. In order to
address the specific needs of endoscopic and/or laparoscopic
surgical procedures, endoscopic surgical stapling devices have been
developed. An example of an endoscopic surgical stapling device is
disclosed, for example, in U.S. Pat. No. 8,070,033 to Milliman et
al., the entire contents of which is incorporated herein by
reference.
[0008] It would be extremely beneficial to provide a surgical
device for use during laparoscopic and/or endoscopic surgical
procedures that can be employed to provide multiple firings of the
surgical device without requiring removal of the surgical device
from the surgical site.
SUMMARY
[0009] In accordance with the present disclosure, a surgical
stapling apparatus for sequentially applying a plurality of
fasteners to body tissue and simultaneously incising tissue is
provided. The surgical stapling apparatus is configured to receive
a disposable loading unit including a plurality of retention slots
disposed in a plurality of rows for receiving a plurality of
staples therein. Each retention slot includes a staple magazine
operatively associated therewith for supplying staples for
subsequent firing.
[0010] In one aspect of the present disclosure a surgical stapling
apparatus is disclosed including a handle assembly, an elongated
body extending distally from the handle assembly and defining a
longitudinal axis, and a disposable loading unit supported at the
distal end of the elongated body. The disposable loading unit
includes an anvil assembly and a cartridge assembly. The cartridge
assembly includes at least one cartridge having a first half and a
second half, a first row of retention slots disposed in the first
half of the at least one cartridge, a second row of retention slots
disposed in the second half of the at least one cartridge, a third
row of retention slots being alternately disposed in the first half
and the second half of the at least one cartridge between the first
and second rows of staple receiving slots, a plurality of fasteners
disposed in the retention slots of the first, second and third
rows, and a plurality of pushers disposed in each of the first and
second halves of the cartridge. Each pusher is disposed in
operative association with at least one of the retention slots of
the cartridge assembly and is configured to eject a respective
fastener from the at least one retention slot during firing of the
surgical stapling apparatus.
[0011] In an aspect of the present disclosure, the at least one
cartridge is a pair of cartridges configured to couple together at
a distal end portion thereof and defining a longitudinal slot
therebetween when coupled together.
[0012] In an aspect of the present disclosure, the longitudinal
slot is configured to facilitate passage of a knife blade
therethrough.
[0013] In an aspect of the present disclosure, the first and second
halves of the at least one cartridge include corresponding flanges
and channels. The channels of the first and second halves are
configured to receive corresponding flanges of the first and second
halves, respectively, when the first and second halves are coupled
together.
[0014] In an aspect of the present disclosure, the flanges of the
first and second halves include the retention slots of the second
row therein.
[0015] In an aspect of the present disclosure, the cartridge
assembly further includes a cartridge support channel configured to
receive the first and second halves of the at least one cartridge
therein to maintain the first and second halves in engagement with
one another.
[0016] In an aspect of the present disclosure, each retention slot
of the at least one cartridge includes a staple magazine disposed
in operative association therewith and including a plurality of
fasteners therein. The staple magazine is configured to supply one
of the plurality of fasteners of the staple magazine to the
corresponding retention slot after a firing of the surgical
stapling device.
[0017] In an aspect of the present disclosure, the plurality of
fasteners disposed in the retention slots and staple magazines of
the first row have a first size, the plurality of fasteners
disposed in the retention slots and staple magazines of the second
row have a second size, and the plurality of fasteners disposed in
the retention slots and staple magazines of the third row have a
third size. In an aspect of the present disclosure the first,
second and third sizes are substantially the same. In another
aspect of the present disclosure, the first size is greater than
the second and third sizes and the third size is greater than the
second size. In another aspect of the present disclosure, the first
size is greater than the second and third sizes and the second and
third sizes are the same. In another aspect of the present
disclosure, the first and second sizes are the same and the third
size is smaller than the first and second sizes.
[0018] In an aspect of the present disclosure, the first half
defines a first tissue contacting surface, the second half defines
a second tissue contacting surface, and the first and second
halves, when coupled together, define a third tissue contacting
surface. In an aspect of the present disclosure, it is contemplated
that a height of each of the first and second tissue contacting
surfaces is substantially the same, that a height of the first and
third tissue contacting surfaces is substantially the same, that a
height of the second and third tissue contacting surfaces is
substantially the same or that a height of each of the first,
second and third tissue contacting surfaces is substantially the
same. In another aspect of the present disclosure, the height of
the first tissue contacting surface is greater than one or both of
the heights of the second and third tissue contacting surfaces. In
another aspect of the present disclosure, the height of the second
tissue contacting surface is greater than one or both of the
heights of the first and third tissue contacting surfaces. In
another aspect of the present disclosure, the height of the third
tissue contacting surface is greater than one or both of the
heights of the first and second tissue contacting surfaces.
[0019] In an aspect of the present disclosure, the staple magazine
includes a biasing member configured to bias the plurality of
fasteners disposed in the staple magazine toward the corresponding
retention slot. In an aspect of the present disclosure, the biasing
member is a leaf spring.
[0020] In an aspect of the present disclosure, each of the
plurality of pushers includes at least one pusher plate disposed
within at least one of the retention slots of the first, second and
third rows. The at least one pusher plate is configured to
translate through the respective retention slot to eject the
respective fastener disposed therein.
[0021] In an aspect of the present disclosure, each of the
plurality of pushers is configured to cover an opening disposed
between a respective retention slot and the corresponding staple
magazine when translating through the respective retention slot to
a fired position to eject the respective fastener disposed therein,
and to uncover the opening disposed between the respective
retention slot and the corresponding staple magazine when
translating back to a pre-fired position after the respective
fastener has been ejected from the respective retention slot,
thereby allowing the corresponding staple magazine to re-supply the
respective retention slot with one of the plurality of fasteners
disposed in the corresponding staple magazine.
[0022] In an aspect of the present disclosure, the surgical
stapling apparatus includes a firing cam assembly that is
translatably disposed within the disposable loading unit. The
firing cam assembly includes a plurality of drive bars. Each drive
bar includes a firing cam disposed at a distal end thereof and is
configured to translate through one of the first and second halves
of the at least one cartridge to engage and drive each pusher to
eject the fastener from the corresponding retention slot during
firing of the surgical stapling apparatus.
[0023] In an aspect of the present disclosure, each of the first
and second halves of the at least one cartridge includes a
longitudinal slot extending therethrough configured for the
reception of one of the plurality of drive bars therethrough.
[0024] In an aspect of the present disclosure, each firing cam
includes a camming slot configured to receive the plurality of
pushers therein during a distal translation of the firing cam
assembly to translate the plurality of pushers between a pre-fired
position and a fired position.
[0025] In an aspect of the present disclosure, each pusher includes
a proximal camming surface and each camming slot of each firing cam
includes a firing cam surface. The firing cam surface is configured
to engage the proximal camming surface of the pusher during distal
translation of the respective drive bar to translate the pusher to
the fired position and cause the pusher to eject the respective
fastener from the at least one retention slot.
[0026] In an aspect of the present disclosure, each pusher includes
a distal camming surface and each camming slot includes a
retracting cam surface. The retracting cam surface is configured to
engage the distal camming surface of the pusher during proximal
translation of the respective drive bar to cause the pusher to
return to the pre-fired position.
[0027] In an aspect of the present disclosure, each camming slot
includes a proximal portion proximal of the firing cam surface that
is configured to maintain each pusher disposed therein in the fired
position.
[0028] In an aspect of the present disclosure, a surgical stapling
apparatus is disclosed including a handle assembly, an elongated
body extending distally from the handle assembly and defining a
longitudinal axis, and a disposable loading unit supported at the
distal end of the elongated body. The disposable loading unit
includes an anvil assembly and a cartridge assembly. The cartridge
assembly includes a plurality of retention slots disposed in a
plurality of rows, each retention slot including a fastener
disposed therein, and a staple magazine disposed in operative
association with each retention slot. The staple magazine includes
a plurality of fasteners and a biasing member disposed therein. The
biasing member is configured to bias the plurality of fasteners
towards the corresponding retention slot. The staple magazine is
configured to reload the corresponding retention slot with one of
the plurality of fasteners after a firing of the surgical stapling
apparatus.
[0029] In an aspect of the present disclosure, the plurality of
rows of retention slots include at least a first row of retention
slots and a second row of retention slots. In an aspect of the
present disclosure, the fasteners disposed in the first row of
retention slots have a first size and the fasteners disposed in the
second row of retention slots having a second size. In an aspect of
the present disclosure, the first size is substantially equal to
the second size. In another aspect of the present disclosure, the
first size is greater than the second size. In another aspect of
the present disclosure, the second size is greater than the first
size.
[0030] In an aspect of the present disclosure, the plurality of
fasteners of each staple magazine corresponding to the retention
slots of the first row have the first size and the plurality of
fasteners of each staple magazine corresponding to the retention
slots of the second row have the second size.
[0031] In an aspect of the present disclosure, a cartridge assembly
for use with a disposable loading unit of a surgical stapling
apparatus is disclosed including a first cartridge and a second
cartridge coupled to the first cartridge. Each of the first and
second cartridges includes a first cartridge half and a second
cartridge half and each cartridge half includes a longitudinal slot
extending therethrough and a plurality of retention slots disposed
therein. Each retention slot includes a fastener disposed therein
and each cartridge half further includes a plurality of pushers
disposed therein in operative communication with the longitudinal
slot and the plurality of retention slots. The cartridge assembly
further includes a plurality of drive bars configured for
translation through the cartridge assembly. Each drive bar is
configured to translate through the longitudinal slot of one of the
cartridge halves, whereby upon distal translation of one of the
plurality of drive bars through the longitudinal slot of one of the
cartridges halves, the one of the plurality of drive bars
individually engages each pusher of the respective cartridge half
to drive each pusher to sequentially eject the fastener from the
associated retention slot.
[0032] Any of the above aspects of the present disclosure described
may be combined with any other aspect of the present disclosure
without departing from the scope of the present disclosure.
BRIEF DESCRIPTION OF DRAWINGS
[0033] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate embodiments of
the disclosure and, together with a general description of the
disclosure given above and the detailed description of the
embodiments given below, serve to explain the principles of the
disclosure, wherein:
[0034] FIG. 1 is a perspective view of an exemplary surgical
stapling apparatus according to the present disclosure;
[0035] FIG. 2 is a perspective view of the surgical stapling
apparatus of FIG. 1 with the disposable loading unit detached and
the shaft rotated 90.degree.;
[0036] FIG. 3 a perspective view of the disposable loading unit of
the surgical stapling apparatus of FIG. 1;
[0037] FIG. 4 is a cross-sectional view of the disposable loading
unit of FIG. 3 taken along section line 4-4;
[0038] FIG. 4a is a cross-sectional view of the disposable loading
unit of FIG. 3 taken along section line 4-4, illustrating the knife
assembly disposed in the central channel and an anvil assembly;
[0039] FIG. 5 is a perspective view of a two plate pusher in
accordance with the present disclosure;
[0040] FIG. 6 is a perspective view of the cartridge assembly of
the disposable loading unit of FIG. 3;
[0041] FIG. 7 is a exploded view of the cartridge assembly of FIG.
6, illustrating a pair of cartridges and a carrier;
[0042] FIG. 8 is an exploded view of one of the cartridges of FIG.
7, illustrating two cartridge halves and a cartridge support
channel;
[0043] FIG. 9 is an exploded view of one of the cartridge halves of
FIG. 8, illustrating the pushers, biasing members and fasteners
removed;
[0044] FIG. 10 is an enlarged, partially exploded, view of the
distal end of one of the cartridge halves of FIG. 8 indicated by
the area of detail 10;
[0045] FIG. 11 is a cross-sectional view of the cartridge assembly
of FIG. 6, taken along section line 11-11;
[0046] FIG. 12 is an enlarged view of the distal end portion of the
cartridge assembly of FIG. 11 indicated by the area of detail
12;
[0047] FIG. 13 is a top down view of the firing cam assembly of the
cartridge assembly of FIG. 11;
[0048] FIG. 14 is a perspective view of the firing cam assembly of
FIG. 13;
[0049] FIG. 15 is an exploded view of the firing cam assembly of
FIG. 14;
[0050] FIG. 16 is a side, cross-sectional view of the cartridge
assembly of FIG. 6, taken along section line 16-16; and
[0051] FIGS. 17-19 are enlarged cross-sectional views of the
cartridge assembly of FIG. 4 indicated by the areas of detail 17,
18, 19 in FIG. 4, illustrating the firing and re-loading of a
retention slot.
DETAILED DESCRIPTION OF EMBODIMENTS
[0052] Embodiments of the presently disclosed surgical stapling
apparatus will now be described in detail with reference to the
drawings wherein like numerals designate identical or corresponding
elements in each of the several views. As is common in the art, the
term "proximal" refers to that part or component closer to the user
or operator, i.e. surgeon or physician, while the term "distal"
refers to that part or component farther away from the user.
[0053] FIGS. 1-2 illustrate one embodiment of the presently
disclosed surgical stapling apparatus shown generally as 10.
Briefly, surgical stapling apparatus 10 includes a handle assembly
12 and an elongated body 14. A loading unit or DLU 16 is releasably
secured to a distal end of elongated body 14. loading unit 16
includes a tool assembly 18 having a cartridge assembly 20 housing
a plurality of surgical staples and an anvil assembly 22 pivotably
coupled in relation to cartridge assembly 20. A detailed
description of the function of handle assembly 12, elongated body
14 and similar features of the loading unit 16 are disclosed in
U.S. Pat. No. 8,070,033 to Milliman et al. the entire contents of
which are incorporated herein by reference. Once the surgical
stapling apparatus 10 has been fired, the practitioner may remove
the DLU 16, as described hereinabove, and install a new DLU 16.
[0054] Handle assembly 12 includes a stationary handle member 24, a
movable handle member 26, and a barrel portion 28. Movable handle
member 26 is operably coupled to loading unit 16 such that upon
actuation of movable handle member 26, e.g., relative to stationary
handle member 24, loading unit 16 is also actuated to grasp tissue
and/or to fire and form fasteners through the grasped tissue.
[0055] A rotatable member 30 is preferably mounted on the forward
end of barrel portion 28 to facilitate rotation of elongated body
14 with respect to handle assembly 12. For example, upon actuation,
e.g. rotation, of rotatable member 30, elongated body 14 and
loading unit 16 are also rotated. Rotatable member 30 may be
rotated, for example, up to 180.degree. in each direction.
[0056] Referring now to FIG. 2, with rotatable member 30 rotated
90.degree., a coupling mechanism 15 is shown. Coupling mechanism 15
is operably associated with elongated body 14 and loading unit 16
and is configured to control the coupling therebetween when loading
unit 16 is coupled to elongated body 14. Loading unit 16 may be
coupled to elongated body 14 by a coupling mechanism 15 such as a
bayonet coupling, a snap fit coupling, or a similar coupling and
may be secured in place by coupling mechanism 15. A release switch
15a is operatively associated with coupling mechanism 15 and is
configured to release or decouple loading unit 16 from elongated
body 14. In this manner, a used loading unit 16 may be removed and
a new loading unit 16 may be coupled to elongated body 14.
[0057] An articulation lever 32 is also preferably mounted on the
forward end of barrel portion 28 adjacent rotatable member 30 to
facilitate articulation of tool assembly 18. For example, upon
actuation of articulation lever 32 in a first direction, tool
assembly 18 may also articulate in the first direction, and upon
actuation of articulation lever 32 in a second direction, tool
assembly 18 may also articulate in the second direction. It is also
contemplated that tool assembly 18 may articulate in a direction
opposite to the direction that articulation lever 32 is
actuated.
[0058] A retraction member 34 is movably positioned along barrel
portion 28 and operatively associated with tool assembly 18.
Retraction member 34 is actuatable to return surgical stapling
apparatus 10 to a retracted, or pre-fired, position. During
operation, as movable handle member 26 is actuated to fire the
surgical stapling device, retraction member 32 is translated
distally. The position of retraction member 34 is maintained in
place by a locking mechanism (not shown). A release button 35 is
provided for temporarily deactivating this locking mechanism. Upon
actuation of release button 35, retraction member 34 is no longer
locked in place.
[0059] Referring to FIG. 3, loading unit 16 includes a proximal
housing portion 100 adapted to releasably engage the distal end of
body portion 14 (FIGS. 1 and 2). A mounting assembly 102 is
pivotally secured to the distal end of housing portion 100, and is
configured to receive the proximal end of tool assembly 18 such
that pivotal movement of mounting assembly 102 about an axis
perpendicular to the longitudinal axis of housing portion 100
effects articulation of tool assembly 18.
[0060] Referring to FIGS. 3-10, tool assembly 18 preferably
includes cartridge assembly 20 and anvil assembly 22 having staple
forming pockets 22a (FIG. 18) disposed thereon. An example of a
suitable anvil assembly 22 is disclosed in U.S. Pat. No. 5,865,361
to Milliman et al., referenced above. Cartridge assembly 20
includes a carrier 202 which defines an elongated support channel
204 (FIG. 7). Elongated support channel 204 is dimensioned and
configured to receive a pair of staple cartridges 206, 208.
Corresponding tabs 210 and slots 212 formed along staple cartridges
206, 208 and elongated support channel 204, respectively, function
to retain staple cartridges 206, 208 within support channel 204. A
support strut 214 formed along each staple cartridge 206, 208 is
positioned to rest on a side wall of carrier 202 to further
stabilize staple cartridges 206, 208 within support channel
204.
[0061] With reference now to FIGS. 6 and 7, staple cartridges 206,
208 are configured to couple together at a distal end portion 216
and define a central longitudinal slot 252 therebetween to
facilitate passage of knife assembly 308 (FIG. 14) therethrough. An
inner hole 222 formed on a surface of the distal end portion 216 of
one of staple cartridges 206, 208 is configured to receive an inner
tab 224 formed on a surface of the distal end portion 216 of the
other of staple cartridges 206, 208. Inner hole 222 and inner tab
224 function to align staple cartridges 206, 208 when coupled
together. Inner hole 222 and inner tab 224 in conjunction with tabs
210, slots 212, and struts 214 also function to maintain staple
cartridges 206, 208 in a longitudinally fixed relation when
inserted into elongated support channel 204 of carrier 202.
[0062] With reference now to FIG. 8, each staple cartridge 206, 208
includes an inner half 226 and an outer half 228 configured to
engage and couple to inner half 226. Each half 226, 228 includes
retention slots 230 formed therein for receiving a plurality of
fasteners 110 and pushers 108. Each fasteners 110 includes a pair
of legs 112 having tips 110d and a backspan 110e. Retention slots
230 are aligned in rows, so that when inner half 226 and outer half
228 are coupled together, for example, three rows of retention
slots 230 are defined. It is contemplated that cartridge halves
226, 228 may include fewer rows or additional rows of retention
slots.
[0063] Outer half 228 includes a first row 234 of retention slots
230 and at least a portion 236a of a second row 236 of retention
slots 230. Inner half 226 includes a third row 238 and at least a
remaining portion 236b of the second row 236 of retention slots
230. When outer half 228 and inner half 226 are coupled together,
the second row 236 of retention slots 230 is defined by the
combination of portions 236a and 236b. For example, portions 236a
and 236b may alternately define retention slots 230 of second row
236 as illustrated in FIG. 8.
[0064] Each of inner half 226 and outer half 228 includes a
plurality of flanges 240 and a plurality of channels 242. Channels
242 are configured to receive flanges 240 during coupling of inner
half 226 to outer half 228 such that the channels 242 of each of
inner and outer halves 226, 228 match up with the flanges 240 of
the other of inner and outer halves 226, 228 when the inner and
outer halves 226, 228 are joined together. Channels 242 and flanges
240 may alternate along the length of each of inner half 226 and
outer half 228, as illustrated in FIG. 8. Each flange 240 includes
one of retention slots 230 of second row 236. Retention slots 230
of flanges 240 may be configured such that when inner half 226 and
outer half 228 are coupled together, flanges 240, and the retention
slots 230 disposed therein, are substantially longitudinally
aligned to form second row 236. Alternatively, retention slots 230
of flanges 240 of each of inner and outer halves 226 and 228 may be
slightly offset from a longitudinal axis such that retention slots
230 of flanges 240 of respective inner and outer halves 226 and 228
are not substantially longitudinally aligned.
[0065] Referring now to FIGS. 4 and 6-8, each cartridge 206, 208
includes a cartridge support channel 254 dimensioned and configured
to receive inner and outer halves 226 and 228. Cartridge support
channel 254 is configured to maintain inner and outer halves 226
and 228 in engagement in longitudinal alignment with one another.
Inner and outer halves 226 and 228 include recessed sections 256
dimensioned and configured for receiving cartridge support channel
254 such that cartridge support channel 254 is substantially
aligned with side surfaces 258 of inner and outer halves 226 and
228. This assists in maintaining inner and outer halves 226, 228
coupled together without adding additional width to each cartridge
206, 208 thereby maintaining a minimal width of the overall
cartridge assembly 20.
[0066] Referring now to FIG. 4, in any of the embodiments disclosed
herein, one or more of the cartridges 206, 208 includes a tissue
contacting surface 104 that is stepped. For example, an outer
tissue contacting surface 104a, an intermediate tissue contacting
surface 104b, and an inner tissue contacting surface 104c form a
stepped configuration. Each tissue contacting surface 104a-104c has
a different height from one another as measured from a bottom
surface 106 of a respective cartridge 206, 208. Specifically,
tissue contacting surfaces 104a-104c are planar structures that are
substantially parallel to one another, but are not co-planar (i.e.
stepped) with one another. In addition, each tissue contacting
surface 104a-c defines a planar axis that extends through the
respective tissue contacting surface 104a-c. A first wall surface
interconnects tissue contacting surfaces 104a and 104b, while a
second wall surface interconnects tissue contacting surfaces 104b
and 104c. The first and second wall surfaces are planar structures
wherein each wall surface defines a planar axis. In one embodiment,
the planar axes of the wall surfaces are orthogonal to the planar
axes of tissue contacting surfaces 104a-c. In one embodiment, inner
tissue contacting surface 104c is defined on inner half 226 of each
cartridge 206, 208, outer tissue contacting surface 104a is defined
on outer half 228 of cartridge, and intermediate tissue contacting
surface 104b is defined by the joining of inner half 226 and outer
half 228 when inner and outer halves 226, 228 are coupled
together.
[0067] Inner tissue contacting surface 104c has the greatest
height, outer tissue contacting surface 104a has the least height,
and intermediate tissue contacting surface 104b has a height
between the heights of outer and inner tissue contacting surfaces
104a, 104c (see FIG. 4). While tissue contacting surfaces 104a-104c
are shown as increasing in height from outer most tissue contacting
surface 104a to inner most tissue contacting surface 104c, it is
within the scope of the present disclosure that the heights of each
tissue contacting surface can vary depending on the particular
surgical procedure. For example, tissue contacting surfaces
104a-104c can increase in height from the inner most tissue
contacting surface 104c to the outer most tissue contacting surface
104a, the intermediate tissue contacting surface 104b can have the
greatest height, the intermediate tissue contacting surface 104b
can have the least height, or at least two of tissue contacting
surfaces 104a-104c can have the same height.
[0068] As seen in FIG. 4, each row 234, 236, 238 may include
fasteners 110 having different sizes. For example, legs 112a of
surgical fasteners 110a disposed in retention slots 230 of first
row 234 may have a first leg length, legs 112b of surgical
fasteners 110b disposed in retention slot 230 of second row 236 may
have a second leg length, and legs 112c of surgical fasteners 110c
disposed in retention slot 230 of third row 238 may have a third
leg length. In particular, surgical fasteners 110a-110c increase in
height from the inner most row 238 to the outermost row 234 of each
cartridge. In one embodiment, legs 112c of surgical fasteners 110c
have a leg length of about 2.3 mm, legs 112b of surgical fasteners
110b have a leg length of about 3.5 mm, and legs 112a of surgical
fasteners 110a have a leg length of about 4.1 mm. As such, inner
tissue contacting surface 104c has the greatest height and retains
surgical fasteners 110c having the shortest leg lengths, and outer
tissue contacting surface 104a has the least height and retains
surgical fasteners 110a having the longest leg lengths. Tissue
contacting surface 104 step progressively downward at intermediate
tissue contacting surface 104b and then again at outer tissue
contacting surface 104a. It is envisioned and within the scope of
the present disclosure that any number of arrangements are
possible. In any of the embodiments disclosed herein, the cartridge
or cartridges can include staples of different sizes or the
cartridge or cartridges can have staples that are all the same
size.
[0069] With reference now to FIGS. 4 and 8-10, each retention slot
230 of inner and outer halves 226 and 228 has a staple magazine 244
operatively associated therewith. The staple magazine is positioned
in a flange 240. Each staple magazine 244 includes a plurality of
fasteners 110 disposed therein and a biasing member 246 configured
to bias and urge the plurality of fasteners 110 towards the
respective retention slot 230. As discussed above, retention slots
230 that are disposed on different rows 234, 236 and 238 may
include fasteners 110 having different sizes. It is further
contemplated that each magazine 244 associated with an adjacent
retention slot 230 includes a plurality of fasteners 110 having the
same size as the fastener 110 disposed in the adjacent retention
slot 230. For example, magazines 244 associated with retention
slots 230 of first row 234 may include fasteners 110a have the
first size, magazines 244 associated with retention slots 230 of
second row 236 may include fasteners 110b have the second size, and
magazines 244 associated with retention slots 230 of third row 238
may include fasteners 110c have the third size.
[0070] Referring now to FIG. 10, staple magazine 244 generally
defines a "U" or "H" shaped channel 248 for reception of fasteners
110 therein. Channel 248 includes a pair of vertical segments 248a,
248b and a horizontal segment 248c. With reference to FIG. 5, each
fastener 110 disposed within channel 248 is maintained in a
vertical orientation, with tips 110d oriented toward the tissue
contacting surface 104 of the respective cartridge 206, 208, and
aligned parallel to a plane defined by the fastener 110 disposed
within the respective retention slot 230. For example, the backspan
110e of a fastener 110 disposed within channel 248 of magazine 244
rests on horizontal segment 248c and the legs 112 of the fastener
110 disposed within channel 248 are disposed within vertical
segments 248a and 248b. This ensures that when a fastener 110 is
loaded from a magazine 244 into a respective retention slot 230,
the fastener 110 is properly oriented toward the tissue contacting
surface 104 for firing.
[0071] Each magazine 244 includes at least one channel 244a for
receiving at least a portion of biasing member 246 therethrough
where biasing member 246 is configured to extend from the at least
one channel 244a into at least one of vertical segments 248a and
248b adjacent the plurality of fasteners 110 disposed in magazine
244 to engage the plurality of fasteners 110 and urge the plurality
of fasteners 110 towards the respective retention slot 230. It is
contemplated that a separate biasing member 246 may extend into
each vertical segment 248a and 248b. In an embodiment, biasing
member 246 includes a pair of legs 246b, 246c, and a backspan 246d
where the pair of legs 246b, 246c extends into vertical segments
248a, 248b, respectively when biasing member 246 is inserted into
channel 244a of magazine 244.
[0072] With reference now to FIG. 4, legs 246b and 246c of biasing
member 246 may define a slight curve such that when biasing member
246 is inserted into channel 244a of magazine 244 and engages the
plurality of fasteners 110 disposed therein, legs 246b and 246c
bias the plurality of fasteners 110 toward the respective retention
slot 230 and in vertical registration with the respective retention
slot 230. Biasing member 246 is inserted into channel 244a in a
substantially vertical manner and upon encountering one in the
plurality of fasteners 110, legs 246b and 246c are deflected
outward and engage the plurality of fasteners with a biasing force
"F". Biasing member 246 may be formed of any resilient or flexible
material which resists deformation or applies a force to return to
its pre-deformation state.
[0073] Biasing member 246 may be any suitable mechanism for biasing
the plurality of fasteners 110 disposed in magazine 244 toward
retention slot 230, as described above, including, for example,
springs, resilient members, or other similar biasing elements. In
one embodiment, biasing member 246 is a leaf spring 246a having a
substantially "U" shape. It is contemplated that biasing member 246
may have other shapes suitable for use in biasing fasteners 110
disposed in magazine 244 toward retention slot 230.
[0074] With reference now to FIGS. 4, 5, 9, and 16-19, a plurality
of pushers 108 are disposed within each of the inner and outer
halves 226, 228 of cartridges 206, 208 and are operatively
associated with the plurality of retention slots 230. Each pusher
108 includes a pusher plate 108c disposed within one of retention
slots 230 and in operative association with the fastener 110
disposed within the respective retentions slot 230. Each pusher
plate 108c is configured to translate through the respective
retention slot 230 to urge the fastener 110 disposed therein out of
the retention slot 230 through a respective opening 230a in tissue
contacting surface 104, through tissue disposed between anvil
assembly 22 and the cartridge assembly 20, and against staple
forming pockets 22a (FIG. 18) of anvil assembly 22.
[0075] In one embodiment, as illustrated in FIG. 4, pusher plates
108c disposed in the retention slots 230 of first row 234 may have
a first size, pusher plates 108c disposed in the retention slots
230 of second row 236 may have a second size, and pusher plates
108c disposed in retention slots 230 of third row 238 may have a
third size. For example, pusher plates 108c of the first row 234
may be smaller than pusher plates 108c of second row 236, and
pusher plates 108c of second row 236 may be smaller than pusher
plates 108c of third row 238. Having pusher plates 108c with
different sizes allows pusher plates 108c to accommodate fasteners
110a-110c having different sizes or allows pusher plates 108c to
accommodate rows 234, 236, 238 having tissue contacting surfaces
104a-c of different heights. Pusher plates 108c of each pusher 108
may alternatively be the same size. A tray or other member may be
provided to maintain the position of the pushers prior to the
staple cartridge being installed in the cartridge support
channel.
[0076] Each pusher 108 may be operatively associated with one or
more retention slots 230 such that upon actuation thereof, pusher
108 may fire one or more fasteners 110 out of retention slots 230
through openings 230a. For example, as illustrated in FIG. 5, a
pusher 108a including two pusher plates 108c is configured to fire
two fasteners 110. As illustrated in FIG. 9, cartridge halves 226,
228 may include more than one type of pusher where, for example,
pushers 108a, including two pusher plates 108c, that are configured
for operative association with two retention slots 230 may be
disposed at either end of the respective row 234, 236, 238, and
pushers 108b, including three pusher plates 108c, that are
configured for operative association with three retention slots 230
may be disposed between the ends of the respective rows 234, 236,
238. It is contemplated that alternate arrangements are possible
where two and three retention slot pushers 108a, 108b may be
included in any order. Alternatively, only one type of pusher 108
may be used, e.g., only pushers 108a configured for use with two
retention slots or only pushers 108b configured for use with three
retention slots. In this manner, each retention slot 230 is
operatively associated with a pusher 108 that is configured to fire
a fastener 110 disposed therein. It is alternatively contemplated
that each pusher 108 may only include one pusher plate 108c and may
only be associated with a single retention slot 230 or that each
pusher 108 may include a plurality of pusher plates 108c configured
for use with a plurality of retention slots 230.
[0077] Referring now to FIGS. 17-19, during firing, as a pusher
plate 108c translates through a corresponding retention slot 230 to
a fired position, pusher plate 108c at least partially blocks or
covers an opening 232 between retention slot 230 and magazine 244
to inhibit reloading of retention slot 230 with a new fastener 110
by magazine 244 until the firing stroke is complete. As pusher
plate 108c returns to its pre-fired position at the base of
retention slot 230, opening 232 is uncovered or opened to magazine
244 and receives the next fastener 110 from magazine 244 due to
biasing force "F" of biasing member 246. It is contemplated that
the next fastener 110 from magazine 244 may be at least partially
received through opening 232 and within retention slot 230 as
pusher plate 108c returns toward its pre-fired position where, for
example, tips 110d of the next fastener 110 may be received through
opening 232 and within retention slot 230 before backspan 110e is
received through opening 232 and within retention slot 230.
[0078] Referring now to FIGS. 11-19, a firing cam assembly 300 is
disposed at least partially within proximal housing 100 of loading
unit 16 and extends at least partially into tool assembly 18.
Firing cam assembly 300 is disposed in operative communication with
handle assembly 12 and is configured to translate distally and
proximally through tool assembly 18 upon actuation of handle
assembly 12, as will be described below in more detail.
[0079] With reference now to FIGS. 13-15, firing cam assembly 300
includes a plurality of drive bars 302 having firing cams 304
disposed at a distal end thereof and a central drive member 306
having a knife assembly 308 disposed at a distal end thereof. Knife
assembly 308 defines a substantially I-shaped cross section having
a top flange 306a, a bottom flange 308b and a knife blade 308c. As
discussed above, a central longitudinal slot 252 extends along the
length of cartridge assembly 20 between staple cartridges 206, 208
to facilitate passage of central drive member 306 and knife
assembly 308 therethrough. With reference now to FIG. 4A, top
flange 308a is configured to translate through a longitudinal slot
22b of anvil assembly 22 and bottom flange 308b is configured to
translate longitudinally along an underside 202a of carrier
202.
[0080] With reference now to FIG. 11, each half 226, 228 of each
cartridge 206, 208 includes a longitudinal slot 250 extending at
least partially therethrough to accommodate passage of at least one
of drive bars 302 and firing cams 304 of firing cam assembly 300
therethrough. It is contemplated, for example, that each slot 250
may accommodate passage of a single drive bar 302 and firing cam
304 or may accommodate passage of multiple drive bars 302 and
firing cams 304.
[0081] With reference now to FIG. 4A, during operation of surgical
stapling apparatus 10, as firing cam assembly 300 translates
through loading unit 16, knife assembly 308 translates through
longitudinal slot 250 with top flange 306a translating through
longitudinal slot 22a of anvil assembly 22 and bottom flange 306b
translating along underside 202a of carrier 202 to approximate
anvil assembly 22 and cartridge assembly 20 together. As knife
assembly 308 translates through slot 250, knife blade 308c severs
the portion of tissue that is disposed between anvil assembly 22
and cartridge assembly 20 adjacent slot 250.
[0082] With reference now to FIGS. 11, 12 and 16-19, as firing cam
assembly 300 translates through loading unit 16, drive bars 302 of
firing cam assembly 300 translate through the longitudinal slots
250 of each half 226, 228 of each staple cartridge 206, 208. The
Firing cams 304 are advanced into sequential contact with the
pushers 108 associated with retention slots 230, to cause pusher
plates 108c to translate vertically within retention slots 230 and
urge fasteners 110 from retention slots 230 through openings 230a
in tissue contacting surface 104, through tissue disposed between
anvil assembly 22 and the cartridge assembly 20, and against staple
forming pockets 22a of anvil assembly 22 for staple forming.
[0083] As illustrated in FIGS. 11, 13 and 14, drive bars 302 are
initially disposed adjacent to one another within proximal housing
100 of loading unit 16 and are resilient or flexible such that they
may spread out to translate through longitudinal slots 250.
[0084] Referring now to FIGS. 11 and 13-15, firing cam assembly 300
may include, for example, four pairs of drive bars 302a-302d
including four pairs of corresponding firing cams 304a-304d. Each
pair of drive bars 302a-302d corresponds to a respective
longitudinal slot 250a-250d of cartridges 206, 208 and is
translatable through the respective longitudinal slot 250a-250d to
actuate pushers 108 disposed in the respective longitudinal slot
250a-250d to effect firing of fasteners 110 disposed in
corresponding retention slots 230. Drive bars 302a-302d and central
drive member 306 are coupled together at the proximal end by a
retaining member 307.
[0085] Referring now to FIGS. 5 and 16, each pusher 108 includes a
pusher base 108d having a proximal cam surface 108e and a distal
cam surface 108f. Each pusher base 108d is disposed within one of
longitudinal slots 250 with the proximal and distal cam surfaces
108e, 108f being configured for engagement with at least one of
firing cams 304 upon distal translation thereof to cause pusher 108
to translate toward tissue contacting surface 104. Translation of
pusher 108 in turn causes translation of a corresponding pusher
plate 108c through a corresponding retention slot 230 toward tissue
contacting surface 104 to eject fasteners 110 from the
corresponding retention slots 230.
[0086] Referring now to FIGS. 14-16, each drive bar 302 and firing
cam 304 includes a camming slot 310 having a proximal portion 310a
and a distal portion 310b. Distal portion 310b includes an opening
312, a firing cam surface 314 and a retracting cam surface 316.
Opening 312 is configured to receive pusher base 108d therethrough
such that the proximal cam surface 108e of pusher base 108d engages
firing cam surface 314 during distal translation of the firing cam
304. Firing cam surface 314 is sloped such that as proximal cam
surface 108e of pusher base 108d slides along firing cam surface
314, pusher 108 is urged toward tissue contacting surface 104 from
a pre-fired position to a fired position. As pusher 108 is urged
toward tissue contacting surface 104, the corresponding pusher
plate 108c translates through the corresponding retention slot 230
to drive the fastener 110 disposed in the retention slot 230
through the opening 230a of tissue contacting surface 104, through
tissue disposed between anvil assembly 22 and cartridge assembly
20, and against a staple forming pocket 22a of anvil assembly
22.
[0087] Once the pusher base 108d reaches the fired position at a
top portion 314a of firing cam surface 314, drive bar 302 and
firing cam 304 are further translated distally such that pusher
base 108d slides along camming slot 310 towards proximal portion
310a. Proximal portion 310a of camming slot 310 is dimensioned such
that as drive bar 302 and firing cam 304 continue to translate
distally, pusher base 108d remains in the fired position. This
allows the corresponding pusher plate 108c to remain in a position
which at least partially blocks or covers the opening 232 of
retention slot 230 (FIG. 18) to inhibit loading of the next
fastener 110 from the corresponding magazine 244 associated with
the respective retention slot 230. Camming slot 310 extends a
sufficient distance along drive bar 302 to accommodate a full
firing stroke of firing cam assembly 300 where, for example, when
drive bar 302 and firing cam 304 are in a distal most position, a
proximal end 310c of camming slot 310 is disposed adjacent to or
proximal of the proximal most pusher 108.
[0088] During retraction of firing cam assembly 300 after the
firing stroke, the distal cam surfaces 108f of pushers 108 are
engaged by retracting cam surface 316 as drive bar 302 and firing
cam 304 are translated proximally and are driven along retracting
cam surface 316 toward opening 312 of camming slot 310 to return
the pusher 108 from the fired position to the pre-fired position.
As each pusher 108 slides along retracting cam surface 316 of
firing cam 304 toward the pre-fired condition, the corresponding
pusher plate 108c translates toward a base of the corresponding
retention slot 230 and opens up or uncovers the opening 232 of the
corresponding retention slot 230 to the corresponding magazine 244.
Once opening 232 is uncovered, retention slot 230 receives the next
fastener 110 from the magazine 244 due to the biasing force of
biasing member 246. Once firing cam assembly 300 is fully retracted
and each retention slot 230 has been loaded with a new fastener 110
from a corresponding magazine 244, surgical stapling apparatus 10
is ready to perform an additional firing stroke.
[0089] Referring now to FIGS. 4 and 6-10 the assembly of cartridge
assembly 20 will now be described. With reference to FIGS. 4 and 9,
a staple pusher 108 is positioned in operative association with
each retention slot 230 with pusher base 108d being disposed in one
of longitudinal slots 205 of each half 226, 228 of each cartridge
206, 208. Fasteners 110 are loaded into retention slots 230 and
magazines 244 through the "U" or "H" shaped channels 248 and the
biasing members 246 are inserted into the channels 244a of the
magazines 244 such that legs 246b, 246c extend into the vertical
segments 248a, 248b of channels 248 and bias the fasteners 110
toward retention slots 230.
[0090] Once the components of each half 226, 228 of each cartridge
206, 208 have been assembled, inner and outer halves 226, 228 of
each cartridge 206, 208 are joined or coupled together with the
flanges 240 and channels 242 of each half 226, 228 interlocking.
The assembled inner and outer halves 226, 228 are then inserted
into the cartridge support channel 254 which maintains inner and
outer halves 226 and 228 in engagement with one another.
[0091] Referring now to FIGS. 6 and 7, the assembled cartridges
206, 208 are joined together at the distal end portion 216 by inner
tab 224 and inner hole 222 so as to define the central longitudinal
slot 252 therebetween and the joined cartridges 206, 208 are
inserted into elongated support channel 204 of carrier 202 such
that tabs 210 disposed on cartridges 206, 208 are engaged with
slots 212 of carrier 202 and support struts 214 of cartridges 206,
208 rest on the side walls of carrier 202. The cartridge assembly
20 is now assembled and ready for use.
[0092] The operation of surgical stapling device 10 during a
surgical procedure will now be discussed with reference to FIGS. 1,
4A, 12, 13, and 16-18. During the surgical procedure, the surgeon
attaches the loading unit 16 to the elongated body 14 and inserts
the loading unit 16 into the surgical site. The surgeon then
positions tissue between cartridge assembly 20 and anvil assembly
22 and actuates handle assembly 12 to approximate the anvil
assembly 22 with the cartridge assembly 20 to grasp the tissue
disposed therebetween, as described above. The surgeon further
actuates handle assembly 12 to drive firing cam assembly 300
distally through cartridge assembly 20 to fire the surgical
fasteners. It is contemplated that a single actuation of handle
assembly 12 by the surgeon may grasp tissue and fully fire the
surgical stapling device 10. Alternatively, grasping tissue and
firing of the surgical stapling device may require multiple
actuations of handle assembly 12 with each actuation advancing
firing cam assembly 300 a predetermined distance through DLU 16. It
is contemplated that the handle portion can be a motorized handle
assembly. Such motorized handle assembly can include a controller
and/or power source.
[0093] As firing cam assembly 300 translates through cartridge
assembly 20, each pair of drive bars 302a-302d and attached pairs
of firing cams 304a-304d translate through respective longitudinal
slots 250 of one of inner and outer halves 226, 228, of cartridges
206, 208. During distal translation of firing cams 304a-304d, each
firing cam 304 individually engages each pusher 108 of each
cartridge 206, 208 and sequentially drives each pusher 108 towards
the tissue engaging surface 104 and thereby eject fasteners 110
from the retention slots 230 disposed in cartridges 206, 208.
[0094] As discussed above, with reference to FIGS. 16-19, as each
firing cam 304 engages each pusher 108, the proximal cam surface
108e of each pusher 108 engages the firing cam surface 314 of each
firing cam 304 and is driven up the firing cam surface 314 from the
pre-fired position to the fired position, e.g., towards tissue
contacting surface 104. As each pusher 108 is driven towards tissue
contacting surface 104, each pusher plate 108c translates through a
corresponding retention slot 230 to eject a corresponding fastener
110 from the corresponding retention slots 230 through a respective
opening 230a in tissue contacting surface 104, through tissue
disposed between anvil assembly 22 and cartridge assembly 20, and
against staple forming pockets 22a of anvil assembly 22, thereby
forming each fastener 110. As the firing cam 304 continues to
translate distally, pusher base 108d travels along camming slot 310
toward proximal end portion 310a and is maintained in the fired
position, e.g., driven toward tissue contacting surface 104, such
that the corresponding pusher plate 108c blocks or covers the
opening 232 between the retention slot 230 and the corresponding
magazine 244. As firing cam assembly 300 translates distally, knife
assembly 308 also translates distally through central longitudinal
slot 252 to sever the tissue held between the cartridge assembly 20
and anvil assembly 22.
[0095] Once the firing stroke is complete, with firing cam assembly
300 disposed in a distal most position, the surgeon withdraws
retraction member 34 proximally to translate firing cam assembly
300 proximally. As firing cam assembly 300 translates proximally
through cartridge assembly 20, firing cams 304 are translated
proximally through longitudinal slots 250 such that the distal cam
surface 108f of each pusher base 108d engages the retracting cam
surface 316 to drive the pusher base 108d down toward opening 312
and the pre-fired position. As each pusher base 108d is driven
toward opening 312, each pusher is translated away from tissue
contacting surface 104 and each pusher plate 108c is translated
away from tissue contacting surface 104 toward the pre-firing
position within a corresponding retention slot 230. As each pusher
plate 108c is withdrawn to the pre-firing position, the opening 232
between the retention slot 230 and the corresponding magazine 244
is opened or uncovered to allow the next fastener 110 to be
received within the retention slot 230 due to the biasing force "F"
of the corresponding biasing member 246. Once firing cam assembly
300 is fully translated proximally to a pre-firing position, each
retention slot 230 has been reloaded and surgical stapling
apparatus 10 is ready for a second firing stroke. In this manner,
each retention slot 230 is reloaded in-situ and ready for
subsequent use without requiring the surgeon to withdraw the
loading unit 16 from the surgical site or replace the loading
unit.
[0096] It is contemplated that each loading unit 16 may be
configured for multiple firing strokes.
[0097] In any of the embodiments disclosed herein, the drive bars
302 can be configured as more than one bar partially attached to
each other. As shown in FIG. 15, each drive bar is comprised of two
drive bars. Each bar can be attached, or partially attached, to at
least one other adjacent bar, in any of the embodiments disclosed
herein. They may be attached by adhesives or welding. For example,
a drive bar comprised of two bars are welded together at the distal
end, near the cam surface. Each staple pusher is driven by a pair
of such cam bar assemblies, as described in par. 0079 thru 0085.
The assembly has better flexibility and permits articulation.
Welding two or more bars together gives the bar assembly more
stiffness and is desirably welded near the cam surface 304. In any
of the embodiments disclosed herein, a pair of relatively thinner
bars is used, instead of a single relatively thicker bar, which are
at least partially attached to one another.
[0098] It is contemplated that individual features of the above
described embodiments may be combined without departing from the
scope of the present disclosure.
[0099] Although the illustrative embodiments of the present
disclosure have been described herein with reference to the
accompanying drawings, the above description, disclosure, and
figures should not be construed as limiting, but merely as
exemplifications of particular embodiments. It is to be understood,
therefore, that the disclosure is not limited to the precise
embodiments described herein, and that various other changes and
modifications may be effected by one skilled in the art without
departing from the scope or spirit of the present disclosure.
* * * * *