U.S. patent application number 12/137571 was filed with the patent office on 2009-12-17 for partially reusable surgical stapler.
Invention is credited to ANIL K. NALAGATLA, Sudhir B. Patel, Debasish Pradhan.
Application Number | 20090308907 12/137571 |
Document ID | / |
Family ID | 44342929 |
Filed Date | 2009-12-17 |
United States Patent
Application |
20090308907 |
Kind Code |
A1 |
NALAGATLA; ANIL K. ; et
al. |
December 17, 2009 |
PARTIALLY REUSABLE SURGICAL STAPLER
Abstract
A partially reusable surgical stapler for deploying staples into
tissue. The stapler has a body with a distal end, a proximal end
and a longitudinal axis therebetween. The proximal end includes a
handle while the distal end includes a staple cartridge holder and
an opposing anvil. The stapler also has an actuator module for
deploying staples. The actuator module includes at least one
longitudinally movable member for sequentially ejecting staples
towards the anvil. The actuator module is readily removable and
replaceable to and from the body. The components of the stapler
body can be disassembled, reconditioned and reassembled for reuse
in a different surgical procedure.
Inventors: |
NALAGATLA; ANIL K.; (Mason,
OH) ; Patel; Sudhir B.; (Mason, OH) ; Pradhan;
Debasish; (Sambalpur, IN) |
Correspondence
Address: |
PHILIP S. JOHNSON;JOHNSON & JOHNSON
ONE JOHNSON & JOHNSON PLAZA
NEW BRUNSWICK
NJ
08933-7003
US
|
Family ID: |
44342929 |
Appl. No.: |
12/137571 |
Filed: |
June 12, 2008 |
Current U.S.
Class: |
227/175.2 ;
227/176.1; 227/180.1 |
Current CPC
Class: |
A61B 17/07207 20130101;
A61B 2017/0725 20130101; A61B 2017/0023 20130101; A61B 2017/07285
20130101 |
Class at
Publication: |
227/175.2 ;
227/176.1; 227/180.1 |
International
Class: |
A61B 17/068 20060101
A61B017/068 |
Claims
1. A surgical stapler for deploying staples into tissue, said
stapler comprising: a. a body having a distal end, a proximal end
and a longitudinal axis therebetween, said proximal end comprising
a handle and a distal end comprising a staple cartridge channel and
an opposing anvil; and b. an actuator module for deploying staples,
said actuator module including at least one longitudinally moveable
member for sequentially ejecting staples towards said anvil, said
actuating module being readily removable and replaceable to and
from said body.
2. The surgical stapler of claim 1, further including a staple
cartridge containing a plurality of staples, said staple cartridge
being disposed within said staple cartridge channel.
3. The surgical stapler of claim 2, wherein said stapler body
comprises an upper jaw member and a lower jaw member each being
formed as a single piece, said upper jaw member having a pair of
stationary pins and said lower jaw member comprising a pair of
alignment slots, said upper jaw pins being inserted into said lower
jaw slots to align said jaw members.
4. The surgical stapler of claim 3, wherein said stapler further
comprises a latching member for connecting said upper and lower jaw
members together at an intermediate position along said
longitudinal axis of said stapler, said latching member being
moveable relative to said upper and lower jaw members.
5. The surgical stapler of claim 4, wherein said latching member is
moveable relative to said upper and lower jaw members to place said
stapler in a series of different locking states.
6. The surgical stapler of claim 5, wherein said latching member is
formed as a single piece component that can be connected to said
stapler in a closed locking state and disconnected from said
stapler in an open locking state.
7. The surgical stapler of claim 6, wherein said latching member
further comprises a latch pin, said latch pin being insertable into
and removable from a slot on said stapler body for connecting and
disconnecting said latching member to said stapler.
8. The surgical stapler of claim 7, wherein said stapler further
comprises retaining means on said stapler body for retaining said
latching member in said different locking states relative to said
upper and lower jaw members.
9. The surgical stapler of claim 6, wherein said latching member is
a single piece component, and wherein said upper jaw member, said
lower jaw member and said latching member can be disassembled from
said stapler and individually reconditioned for reuse in a
different patient procedure.
10. The surgical stapler of claim 8, wherein said retaining means
can hold said latching member in a pre-close locking state in which
said upper jaw pins are prevented from disengaging from said lower
jaw slots yet said staple cartridge can move relative to said
anvil.
11. The surgical stapler of claim 8, wherein said retaining means
can hold said latching member in a partially locked in state in
which said latching member is connected to said lower jaw member,
yet said upper jaw pins can disengage from said lower jaw slots to
enable said upper and lower jaw members to be separated.
12. The surgical stapler of claim 8, wherein said latching member
further comprises hook latch members moveable relative to opposing
sidewalls of said lower jaw member, said hook latch members
engaging said upper jaw pins in a closed locking state to fix said
upper and lower jaw members together in an operative position.
13. The surgical stapler of claim 7, wherein said actuator module
further comprises structure for facilitating mounting and removal
of said module from said stapler body.
14. The surgical stapler of claim 13, wherein said actuator module
structure comprises a channel-shaped pan holding said at least one
longitudinally moveable member, said pan being insertable into and
removable from a channel-shaped frame of said lower jaw member to
permit said longitudinally moveable members to move between said
pan and said staple cartridge.
15. The surgical stapler of claim 14, wherein said actuator module
further comprises an opening aligned with said stapler body opening
along said longitudinal stapler axis, said latch pin being
insertable into and removable from said actuator module opening
when said pin is connected to said stapler body to hold said
actuator module within said stapler body.
16. The surgical stapler of claim 15, further comprising structure
for connecting and disconnecting staple cartridges to said stapler
body relative to said actuator module, wherein multiple staple
cartridges may be used with a single actuator module within said
stapler body.
17. The surgical stapler of claim 16, wherein said longitudinally
moveable members comprise a cutting member and a pair of staple
actuating bars, and said actuator module further includes a guide
means for aligning said cutting member and staple actuating bars
with a staple cartridge for reciprocal movement between said
actuator module and said staple cartridge.
18. A surgical stapler for deploying staples into tissue, said
stapler comprising: a. an upper jaw member having a proximal end
comprising a handle and a distal end comprising an anvil; b. a
lower jaw member having a proximal channel-shaped frame and a
distal end comprising a staple cartridge channel; c. an actuator
module for deploying staples, said actuator module including at
least one longitudinally moveable member for sequentially ejecting
staples towards said anvil, said actuator module being readily
removable and replaceable to and from said lower jaw channel; d. a
staple cartridge containing a plurality of staples disposed within
said staple cartridge channel; and e. a latching member for
connecting said upper and lower jaw members together at an
intermediate position along a longitudinal axis of said stapler,
said latching member being moveable relative to said upper and
lower jaw members to place said stapler in a series of different
locking states.
19. The surgical stapler of claim 18, wherein said upper jaw
member, said lower jaw member and said latching member are single
piece components that can be disassembled from said stapler,
separately reconditioned, and subsequently reassembled for reuse in
a different tissue stapling procedure.
20. The surgical stapler of claim 18, further comprising retaining
means on said latching member for holding said latching member to
said lower jaw member in one or more of said different locking
states.
21. The surgical stapler of claim 18, wherein said latching member
is in an initial, open state for assembly to said upper and lower
jaw members, and moves relative to said jaw members to a closed,
locked state prior to operation of said stapler to prevent said
latching member from disengaging from said upper and lower jaw
members during use.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to surgical stapling
instruments and, more particularly, to a surgical stapler which can
be disassembled and portions reconditioned and sterilized for reuse
in subsequent surgical procedures, and which includes a removable
actuating module that can be reused with multiple staple cartridges
during a single patient procedure.
BACKGROUND OF THE INVENTION
[0002] Before surgical staplers were introduced, surgeons had to
spend a great deal of time sewing the tissue of patients back
together. This was the most time intensive aspect of a surgical
procedure. Surgical staplers have decreased the amount of time that
a user spends sewing tissue back together. Such surgical staplers
are described in the following issued U.S. patents which are hereby
incorporated herein by reference: U.S. Pat. No. 4,633,861 Chow et
al.; U.S. Pat. No. 4,633,874 Chow et al.; and U.S. Pat. No.
5,129,570 Schulze et al.
[0003] One concern with surgical staplers has been assuring that
the staplers used during a procedure are sterile. Reusable staplers
have typically been relatively complicated mechanical instruments
which are difficult to sterilize after use. Hence, it was once
desired that surgical staplers be completely disposable. As more
than one surgical stapler may be required in a surgical procedure,
for economical reasons disposable surgical staplers having
reloadable staple cartridges have been developed. These reloadable
staple cartridges have comprised a combination of staples and a
firing module for discharging the staples. Typically the cutting
instrument is included in the firing module. Therefore, each time a
stapler is reloaded with a new staple cartridge, a new knife and
firing assembly is also inserted into the stapler. Numerous staple
cartridges are normally used during a single patient procedure,
resulting in the repeated replacement of the knife and firing
elements for the same patient. Since a knife is usually not worn
out after a staple cartridge has been emptied, the knife and firing
assembly could be reused with additional staple cartridges within
the same patient. Reusing the firing assembly within a single
patient procedure would not require additional sterilizing and can
decrease the costs incurred during the procedure. Recently, there
has also been a desire to make portions of a surgical stapler
reusable, so that a portion is disposable and a portion is reusable
in subsequent procedures. Reusing portions of the stapler reduces
the costs associated with surgical procedures, and also decreases
the surgical waste.
[0004] Thus, to reduce the costs associated with surgical
procedures, there is a need for a surgical stapler that can be
disassembled and portions of the stapler reconditioned for
subsequent use. In particular, there is a need for a surgical
stapler in which the firing and cutting components may be reused
with multiple staple cartridges within a single patient procedure
in order to decrease the amount of materials utilized with the
stapler. There is also a need for a surgical stapler that can be
easily assembled and disassembled to allow reconditioning and reuse
of some of the stapler parts. In addition, there is a need for a
partially reusable stapler that incorporates a disposable firing
module to allow the more complex cutting and stapling components to
be easily replaced between surgical procedures. Further, there is a
need for a partially reusable stapler in which the reusable parts
have a simple, one-piece design to facilitate effective
reconditioning of the parts between procedures. The present
invention provides a partially reusable surgical stapler which
achieves these objectives.
SUMMARY OF THE INVENTION
[0005] In accordance with the present invention, a partially
reusable surgical stapler is provided for deploying staples into
tissue. The stapler has a body with a distal end, a proximal end
and a longitudinal axis therebetween. The proximal end includes a
handle while the distal end includes a staple cartridge holder and
an opposing anvil. The stapler also has an actuator module for
deploying staples. The actuator module includes at least one
longitudinally movable member for sequentially ejecting staples
towards the anvil. The actuator module is readily removable and
replaceable to and from the body.
[0006] In another embodiment, the present invention provides a
partially reusable surgical stapler having an upper jaw member with
a proximal handle end and a distal anvil end. A lower jaw member
having a proximal channel-shaped frame and a distal staple
cartridge channel is aligned with the upper jaw. An actuator
module, having at least one longitudinally moveable member for
sequentially ejecting staples towards the anvil, is readily
removable and replaceable to and from the lower jaw frame. A staple
cartridge containing a plurality of staples is removably disposed
within the staple cartridge channel. A latching member for
connecting the upper and lower jaws together is provided at an
intermediate position along a longitudinal axis of the stapler. The
latching member is moveable relative to the upper and lower jaw
members to place the stapler in a series of different locking
states. The different locking states include an assembly state for
connecting and disconnecting the latching member to the jaw
members, and a closed, latched state in which the latching member
is locked to the jaw members.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an isometric view of an exemplary surgical stapler
showing the stapler in a closed position;
[0008] FIG. 2 is a front view of the stapler in an open
position;
[0009] FIG. 3 is an isometric view of the stapler in an open
position;
[0010] FIG. 4 is an isometric bottom view of the reusable upper jaw
member for the stapler;
[0011] FIG. 5 is an isometric top view of the stapler upper jaw
member;
[0012] FIG. 6 is an isometric view of the reusable lower jaw member
including the cartridge channel;
[0013] FIG. 7 is an isometric view of the disposable staple
cartridge;
[0014] FIG. 8 is a bottom view of the disposable staple
cartridge;
[0015] FIG. 9 is an isometric view of the reusable latching
member;
[0016] FIG. 10 is a front view of the reusable latching member;
[0017] FIG. 11 is a detailed isometric view of the distal end of
the latching member;
[0018] FIG. 12 is a partial front view of the stapler showing the
latching member in a ready to assemble state;
[0019] FIG. 13 is a partial front view of the stapler showing the
latching member in an initial inserted state;
[0020] FIG. 14 is a partial front view of the stapler showing the
latching member in a rotated and partially locked-in state;
[0021] FIG. 15 is a partial front view of the stapler showing the
relative positions of the latching and upper jaw members in a
pre-close position;
[0022] FIG. 16 is a partial front view of the stapler showing the
relative positions of the latching and upper jaw members in an open
position during use;
[0023] FIG. 17 is an isometric view of the disposable actuating
module;
[0024] FIG. 18 is another isometric view of the disposable
actuating module looking forward from the proximal to the distal
end;
[0025] FIG. 19 is an isometric view of the actuating module
pan;
[0026] FIG. 20 is a detailed, isometric view of the proximal end of
the actuating module;
[0027] FIG. 21 is a top view of the actuating module;
[0028] FIG. 22 is an isometric view of the actuating knob;
[0029] FIG. 23 is an isometric view of the guide block;
[0030] FIG. 24 is an isometric view of a pusher bar;
[0031] FIG. 25 is an isometric view of the knife support bar;
[0032] FIG. 26 is a close-up, isometric view of the distal end of
the actuating module showing the protector cap;
[0033] FIG. 27 is a front view of the actuating module;
[0034] FIG. 28 is a sectional view of the actuating module proximal
end, showing the relationship between the actuating knob and the
detent spring in a full back position; and
[0035] FIG. 29 is a sectional view of the actuating module proximal
end, showing the actuating knob moved forward during firing.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Referring now to the drawing figures, in which like numerals
indicate like elements throughout the views, FIGS. 1 through 3
illustrate a first exemplary surgical stapler 20 of the present
invention. The body of stapler 20 includes an upper jaw member 22,
a lower jaw member 24, and a latching member 30. Latching member 30
is pivotable relative to the upper and lower jaws members 22, 24,
as shown in FIGS. 2-3. Latching member 30 can be pivoted through a
series of different latching states to lock the stapler closed for
use or to open the stapler varying degrees to allow for adjustment
of tissue within the stapler, the replacement of a staple
cartridge, or disassembly of the stapler. Upon completion of a
surgical procedure, latching member 30 can be pivoted to a fully
open position to allow stapler 20 to be disassembled in preparation
for the resterilization and reuse of portions of the stapler.
[0037] As shown in FIGS. 4 and 5, upper jaw 22 comprises a single
piece, elongated channel-shaped frame having a pair of opposing
sidewalls 32a, 32b connected by a top wall 36. Top wall 36 is
suitably shaped on the outer surface to form a hand grip and
includes an upper handle protrusion 40 to facilitate the handling
and operation of the stapler by a surgeon. The distal end of upper
jaw 22 comprises a pair of inwardly extending flanges 42 which
define an anvil 44 of the stapler. Flanges 42 are separated by a
central, longitudinal slot 46 which extends along the entire length
of anvil 44. The inner surface of each flange 42 is provided with
two longitudinal rows of uniformly spaced staple-forming pockets
50. Staple forming pockets 50 allow the fashioning of B-form
staples when U-shaped staples are ejected against the anvil flanges
during firing. Anvil 44 includes a tapered tip at the distal-most
end for facilitating insertion of the stapler into hollow, tubular
body organs. A pair of tissue stops 52 is provided on opposite
sides of anvil 44 adjacent the proximal end of staple forming
pockets 50. Tissue stops 52 are laterally aligned with the proximal
end of staple forming pockets 50 to prevent tissue from being
placed into the stapler beyond anvil 44. Blocking tissue at the
proximal end of anvil 44 prevents the pinching or cutting of
unstapled tissue.
[0038] Cylindrical pins 54 extend from opposite sides of upper jaw
22 proximal of tissue stops 52. Pins 54 fit inside vertical slots
on lower jaw 24 to connect the upper and lower jaws together. Upper
jaw 22 also includes a pair of curved notches 60 near the proximal
end of channel sidewalls 32a, 32b. Notches 60 interact with
projections 62 on lower jaw 24, as shown in FIG. 2, to provide a
means for easily aligning the jaws during use. Upper jaw 22 is
preferably comprised of a single piece of a biocompatible metal,
such as, for example, stainless steel. Using a single piece of
material for upper jaw 22 increases the structural integrity of the
stapler. Alternatively, upper jaw 22 can be manufactured as two or
more separate pieces that are joined together during the
manufacturing process by known joining methods such as, for
example, welding.
[0039] As shown in FIG. 6, lower jaw 24 comprises a single piece,
elongated U-shaped frame having a pair of sidewalls 64a, 64b
connected by a bottom wall 66. At the distal end of lower jaw 24,
side walls 64a, 64b are reduced in size to form a cartridge channel
70 for supporting a single use staple cartridge within the stapler.
Notches 72 are provided in sidewalls 64a, 64b adjacent the distal
end of cartridge channel 70. Notches 72 engage side projections on
the staple cartridge to hold the cartridge within the channel.
Vertical alignment slots 56 are located proximal of cartridge
channel 70 in the upper edge of sidewalls 64a, 64b. As mentioned
above, pins 54 on upper jaw 22 interface with alignment slots 56 to
align and connect the jaw members together. The width between upper
jaw sidewalls 32a, 32b is slightly greater than the width between
lower jaw sidewalls 64a, 64b to enable the upper jaw to fit over
the lower jaw when pins 54 are inserted into alignment slots 56,
and projections 62 into notches 60. Indentations 74 are formed in
the outer surface of sidewalls 64a, 64b, distal of alignment slots
56. Indentations 74 facilitate the attachment of an actuating
module to lower jaw member 24, as will be described in further
detail below.
[0040] An opening 76 is formed through bottom wall 66 at an
intermediate position along lower jaw 24. Sidewalls 64a, 64b extend
downward on opposite sides of opening 76 to form distally angled
projections 80. Along the distal edge of projections 80, sidewalls
64a, 64b are shaped to form a straight-sided slot 82 having a
circular end 88. The diameter of circular end 88 is slightly larger
than the width of the slot 82. Proximal of projections 80 the outer
surfaces of sidewalls 64a, 64b include a latching member
positioning feature. As shown in FIG. 6, the positioning feature
can comprise a plurality of detent bumps 84, or other surface
indentations, that are machined into the surface of the sidewalls
64a, 64b. FIG. 6 shows only a positioning feature on the front side
of lower jaw 24, however, it should be understood that the back
side of the lower jaw is fashioned in the same manner so that
latching member 30 may be retained in a series of latching states
by both sides of the lower jaw, as will be described below. A
retention feature 86 is formed at the proximal end of lower jaw 24
at the junction between sidewalls 64a, 64b and bottom wall 66.
Retention feature 86 can comprise an inward expansion of sidewalls
64a, 64b which facilitates a snap connection with an actuating
module during assembly of stapler 20.
[0041] FIGS. 7 and 8 show an exemplary removable staple cartridge
90 for use in stapler 20 of the invention. Cartridge 90 is adapted
to receive a plurality of surgical staples arranged in at least two
laterally spaced longitudinal rows. Cartridge 90 has a body which
includes opposite side walls 92a, 92b configured to be slidably
received in the interior of lower jaw cartridge channel 70. Staple
cartridge 90 is divided longitudinally by a central elongated slot
94 which extends from the proximal end of the cartridge toward its
distal end. A plurality of staple openings 96, defined by the
cartridge body, are disposed along the elongated center slot 94. In
the illustrated embodiment, the staple openings are arranged in two
laterally spaced, staggered rows, with each pair of rows disposed
on opposite sides of central longitudinal slot 94. The staple
openings in adjacent rows are staggered to provide more effective
stapling of the tissue when the instrument is operated. Referring
to FIG. 8, staple cartridge 90 includes a pair of longitudinal
slots 100 located on opposite sides of elongated central slot 94
and disposed between the staggered rows of openings 96. Each
longitudinal slot 100 extends from the proximal end of cartridge 90
towards the distal end. A plurality of staple drivers (not shown)
are slidably mounted in staple openings 96 for actuating the
staples which are loaded into staple cartridge 90. Each staple
driver is designed to simultaneously actuate two staples located in
the adjacent rows provided in staple cartridge 90. Thus, a first
set of staple drivers is provided for actuating the staples in the
staggered rows located on one side of central longitudinal slot 94,
and a second set of staple drivers is provided for actuating the
staples in the pair of adjacent rows located on the other side of
the central longitudinal slot.
[0042] The distal end of staple cartridge 90 includes a tapered tip
to facilitate the insertion of lower jaw member 24 into a hollow
tubular body organ. Proximal of the tapered tip, staple cartridge
90 is provided with a pair of outwardly extending protrusions 102.
A pair of spaced, parallel flanges 104 extends rearward from
opposite sides of staple cartridge 90. Legs 110 extend downward
from flanges 104 at the proximal end of the staple cartridge. Each
leg 110 is provided with a rounded, downwardly facing notch 112.
When cartridge 90 is assembled on lower jaw 24, protrusions 102 are
loosely received in notches 72 in the lower jaw side walls, and
legs 110 extend through opening 76 in the lower jaw bottom wall 66.
Leg notches 112 engage a pin on latching member 30, as will be
described below, to hold the cartridge within lower jaw channel 70.
A pair of wings 114 extends upward and outward from sidewalls 92a,
92b at the proximal end of cartridge 90. Wings 114 function as
finger grips which allow staple cartridge 90 to be manually
inserted into and removed from lower jaw 24. Using wings 114,
cartridge 90 can be lifted out of jaw opening 76 and notches 72, to
remove the cartridge from lower jaw 24 following use. Additionally,
wings 114 engage lower jaw sidewalls 64a, 64b at the proximal end
of cartridge channel 70, as shown in FIG. 3, to lock the cartridge
in place within lower jaw 24. A short extension 116 is formed at
the rear of cartridge 90 and located between rearwardly projecting
legs 110. Central knife slot 94 extends longitudinally through
extension 116, which can be provided with inwardly sloped guide
surfaces on its opposite sides at the proximal end of the slot. A
lock out pin 106 is connected at one end to extension 116 and is
pivotable about the connection point. Initially, when staple
cartridge 90 is loaded into stapler 20, lock out pin 106 extends
transversely across central knife slot 94.
[0043] As mentioned above, stapler 20 includes a latching member 30
for connecting the upper and lower jaws members together at an
intermediate position along the longitudinal length of the stapler.
Preferably, jaw members 22, 24 are connected together at a location
adjacent to the proximal ends of anvil 44 and staple cartridge 90.
In the preferred embodiment, shown in FIG. 9, latching member 30
comprises a single piece, channeled-shaped frame having opposing
side walls 124a, 124b connected by a top wall 130. Latching member
30 further includes a latch pin 122 for pivotally connecting the
latching member to lower jaw 24. Preferably, the latching member is
comprised of a single piece of stainless steel, or another similar
biocompatible metal. The distance between the opposing latching
member side walls 124a, 124b is sufficient to span the sidewalls
64a, 64b of lower jaw 24. Side walls 124a, 124b include outwardly
extending, elongated flanges 132 which serve as finger grips to
enable latching arm 120 to be manually pivoted between latching
positions. The outer surface of latching arm 120 includes a handle
extension 134. When connected to lower jaw member 24, handle
extension 134 combines with upper jaw handle extension 40 to form a
hand grip for manipulation of the stapler by a surgeon.
[0044] Each side wall 124a, 124b of latching member 30 includes a
distally-extending C-shaped hook member 140 provided with a
forwardly facing notch 142 for engaging upper jaw pins 54. As shown
in FIGS. 9 and 10, hook members 140 include an inner cam surface
144 extending rearward from the tip of the hook member into notch
142. When latching member 30 is moved to a closed, operative state,
notches 142 engage upper jaw pins 54, acting as an over-center
latch to maintain the latching member in the latched state. Below
notches 142, each hook member 140 projects distally downward,
beyond the end of latching member top wall 130. Latch pin 122
extends between the down turned ends of hook members 140, as shown
in FIG. 11, across the end of latching member 30. Latch pin 122 has
a cylindrical shape with flat surfaces 152 adjacent each end. The
diameter of latch pin 122 is greater than the narrow opening for
lower jaw slot 82. Latching member 30 is detachably connected to
lower jaw 24 by inserting latch pin 122 into lower jaw slot 82.
Latch pin 122 is inserted into slot 82 by orienting latching member
30 so that flat ends 152 lie in parallel with the straight sides of
the slot. In this position, latch pin 122 can be inserted into slot
82 despite the pin diameter being greater than the slot width. With
flat ends 152 aligned with the linear sides of slot 82, latch pin
122 is inserted into the slot, as shown in FIG. 12, until the pin
rests within circular slot end 88, as shown in FIG. 13.
[0045] Stapler 20 also includes means for retaining the latching
member in a series of different latching states. Referring to FIGS.
9 and 10, the retaining means includes a spring arm 150 extending
from the top edge of each latching arm sidewall 124a, 124b. Spring
arm 150 curves distally upward, following the upper contour of hook
member 140, and includes a bulbous free end. With latching pin 122
assembled within slot 82, and latching member 30 angled distally,
as shown in FIG. 13, stapler 20 is in an initial, open state. To
close stapler 20, latching member 30 is rotated towards the
proximal end of the stapler, to draw the latching member closer to
the body of lower jaw member 24. As flat ends 152 rotate out of
alignment with the sides of slot 82, the difference in width
between pin 122 and slot 82 prevents the pin from slipping out of
slot end 88. Pin 122 is thus fixed within slot end 88, locking
latching member 30 to lower jaw member 24.
[0046] As latching member 30 rotates, hook members 140 are drawn
along the sides of lower jaw member 24. As hook members 140 swing
alongside lower jaw sidewalls 64a, 64b, the bulbous ends of spring
arms 150 contact detent bumps 84 on the sidewalls. To move spring
arms 150 between the detent bumps 84, additional force is applied
to latching member 30 to cause the spring arms to flex towards the
hook members 140, so that the ends of the spring arms can ride over
the bumps. With spring arms 150 positioned between detent bumps 84,
as shown in FIG. 14, latching member 30 is in a partially locked-in
state. In the partially locked-in state, latching member 30 is
attached to lower jaw 24 and alignment slots 56 are just distal of
the tip of hook members 140. Upper jaw pins 54 can be freely
inserted or removed from lower jaw slots 56, allowing the upper and
lower jaw members to be separated and rejoined together.
[0047] As latch pin 122 continues to rotate within slot end 88,
drawing latching member 30 closer to lower jaw member 24, hook
member inner cam surfaces 144 rotate over the opening of alignment
slots 56, blocking the slots and locking upper jaw pins 54 within
the slots. Spring arms 150 also ride along detent bumps 84 to
engage the concave outer edge of the top bump. In this pre-closed
state, shown in FIG. 15, latching member 30 and upper and lower jaw
members 22, 24 are connected together to form the body of stapler
20, but upper jaw pins 54 can slide within slots 56, between the
bottom of the slot and cam surface 144, to allow some relative
movement between the jaw members. Latching member 30 maintains the
jaw members in a loosely latched position to permit relative
movement between the staple cartridge and anvil. The relative
movement at the distal end of jaw members 22, 24 allows for tissue
adjustments without disconnecting the jaw members from each
other.
[0048] When latching member 30 is rotated to a closed, operative
state (shown in FIG. 1) the latching member surrounds lower jaw
member 24, and pins 54 on upper jaw member 22 are lodged within
hook member notches 142. Spring arms 150 advance distally upward
along the sides of lower jaw member 24 beyond detent bumps 84. In
this state, the upper and lower jaw members are locked together to
compress tissue between the anvil and cartridge surfaces, and the
stapler is ready for stapling and cutting tissue. In the closed
state, a minimum spacing may be maintained between the anvil and
cartridge surfaces by a spacer pin 160. To adjust the placement of
tissue between the anvil and cartridge surfaces, latching member 30
can be rotated back to the pre-close state, as shown in FIG. 16, to
dislodge pins 54 from hook member notches 142. As latching member
30 rotates back, spring arms 150 reengage with detent bumps 84 to
hold the latching member in place. Returning to the pre-close state
loosens the connection between hook members 140 and pins 52, to
allow the pins to slide within slots 56 without disconnecting the
upper and lower jaws.
[0049] To disassemble stapler 20, latching member 30 is rotated
away from lower jaw member 24 to draw upper jaw pins 54 out of hook
notches 142. Latching member 30 may be rotated away from upper and
lower jaw members 22, 24 by pulling on the curved latching arm tip
162. As a counter rotating force continues on latching arm 120,
spring arms 150 move through detent bumps 84, enabling hook members
140 to swing through and way from the lower jaw sidewalls 64a, 64b.
Latching member 30 is rotated around in the direction of staple
cartridge 90 until latching member 30 returns to the initial, open
position shown in FIG. 13. With latching member 30 in the open
state, flat ends 152 on latch pin 122 are again aligned in parallel
with the straight sides of slot 82, enabling the latch pin to be
withdrawn through slot 82 to separate the latching member from
lower jaw member 24. With latching member 30 detached, stapler 20
can be disassembled into three separate, one-piece components,
namely, upper jaw 22, lower jaw 24 and latching member 30. The
one-piece channel-shaped construction of these reusable components
provides for easy yet thorough reconditioning and sterilization of
the components between uses.
[0050] Turning now to FIGS. 17 and 18, which show an actuator
module 170 for stapling and cutting tissue clamped between the
upper and lower jaw members 22, 24. Actuator module 170 comprises a
U-shaped, longitudinal module pan 172 which provides the supporting
structure for the actuator module components. Module pan 172
includes a pair of sidewalls 174 connected together by a bottom
wall 176 (FIG. 19). The distance between module pan sidewalls 174
is less than the distance between lower jaw sidewalls 64a, 64b to
enable the module pan to be slidably mounted within the proximal
channel of lower jaw 24. As shown in FIGS. 19 and 20, the proximal
end of module pan 170 includes one or more detent bumps 178
protruding from the outer surface of sidewalls 174. Detent bumps
178 engage retention features 86 on the inside channel of lower jaw
member 24 when the actuator module 170 is slid proximally into the
lower jaw channel. The interaction of detent bumps 178 with
retention features 86 snaps and retains the actuator module in
place within lower jaw member 24.
[0051] As shown in FIG. 21, a plurality of moveable actuating
members are situated within module pan 172 for longitudinal
movement within the pan relative to upper and lower jaw members 22,
24. The actuating members include a pusher block 180 which is
disposed within module pan 172 for reciprocal, longitudinal
movement within the pan. Pusher block 180 is attached to an
actuator knob 182 by a lateral flange 184. When actuator module 170
is mounted within lower jaw 24, as shown in FIG. 3, flange 184
extends through an elongated guide slot 186 formed in a sidewall 64
of the lower jaw. Flange 184 positions knob 182 on the outside of
jaw members 22, 24 to allow manual access of the knob. In FIG. 3,
knob 182 is shown extending through a guide slot 186 in lower jaw
sidewall 64b. However, a guide slot could also be formed in the
opposite lower jaw sidewall 64a, in which case actuating knob 182
would extend out the opposite side of stapler 20. Flange 184
extends through and rides along guide slot 186 as knob 182 is
manually moved along the outside of jaw members 22, 24.
[0052] Returning now to FIG. 21, actuator module 170 also includes
a pair of longitudinally extending, parallel pusher bars 190. The
proximal ends of pusher bars 190 are secured within laterally
spaced pusher block slots 192 (shown in FIG. 22) to allow the
pusher bars to move longitudinally with pusher block 180 through
module pan 172. Pusher bars 190 extend distally from pusher block
180 and are slidably received in longitudinal slots 194 formed in a
guide block 200, shown in FIG. 23. As shown in FIG. 18, guide block
200 is mounted at the distal end of module pan 172. The upper edges
of module pan sidewalls 174 are bent inward over the side edges of
guide block 200 to retain the guide block within the module pan.
Additionally, tabs 202 extend from the sides of guide block 200
through openings 204 in module pan sidewalls 174 to secure the
guide block within the pan. The distal end of guide block 200
extends beyond the end of module pan 172 and between rear flanges
104 of staple cartridge 90. Lateral slots 194 within guide block
200 align pusher bars 190 with the elongated staple driver slots
100 of staple cartridge 90. The distal ends of pusher bars 190
extend forward of guide slots 194 and are provided with a
wedge-shaped tip 206, shown in FIG. 24, which defines an inclined
cam surface for engaging the staple drivers within cartridge 90 as
the pusher bars are moved distally through the cartridge. The
longitudinal movement of the pusher bar tips 206 sequentially
drives the staple drivers, through a camming action, to fire
staplers from the cartridge.
[0053] Returning to FIG. 23, guide block 200 includes a depending
center section 210 which extends downward through opening 76 in the
lower jaw bottom wall 66. Center section 210 includes a distally
angled, straight-sided slot 212 with a circular end 218. When
stapler 20 is assembled, guide block slot 212 is longitudinally
aligned with slot 82 in lower jaw sidewalls 64a, 64b to enable
latch pin 122 to engage both lower jaw 24 and guide block 200 when
latching member 30 is connected to the stapler. As latch pin 122 is
inserted through slot 82 into slot end 88, the pin also passes
through guide block slot 212 and lodges within circular end 218,
locking the actuator module 170 and lower jaw 24 together.
[0054] As shown in FIGS. 18 and 21, actuator module 170 further
comprises a knife support bar 214 positioned between pusher bars
190. Knife support bar 214 and pusher bars 190 are preferably
manufactured as sheet metal components. The proximal end of knife
support bar 214 is secured within a center slot 216 of pusher block
180 (FIG. 22) to connect the knife support bar to the pusher block
for movement by firing knob 182. Distal of pusher block 180, knife
support bar 214 is slidably received in a center slot 220 formed in
guide block 200 (shown in FIG. 23) to align the knife support bar
with the elongated center slot 94 of the staple cartridge. As shown
in FIG. 25, an inclined knife blade 222 having a beveled cutting
edge is located at the front end of knife support bar 214. The
beveled cutting edge of knife blade 222 is oriented at an angle
relative to jaw members 22, 24, and is slidably received in central
longitudinal slot 220 of guide block 200. Proximal of knife blade
222, knife support bar 214 includes a cartridge locking notch 228
and a locking cut out section 224, which are part of a safety
lockout mechanism described below. The proximal end of knife
support bar 214 includes an offset section, indicated by reference
number 226. Knife offset 226 is formed by cutting away a section of
the knife support bar 214 near the proximal end, to produce two
elevated points 230, 232 on the support bar.
[0055] As shown in FIGS. 26 and 27, a protector cap 234 covers the
distal end of guide block 200. A center section 236 of cap 234
surrounds knife blade 222 and the wedged tips 206 of pusher bars
190. An inwardly directed lip 240 extends along the bottom edge of
the cap. During assembly, downward pressure is applied to protector
cap 234 to snap the distal end of the actuator module in place
inside the lower jaw channel. As cap 234 is pressed downward, cap
lip 240 snaps into indentations 74 on the outer surface of lower
jaw 24.
[0056] A leaf spring 250, shown in FIG. 19, is integrated into
module pan bottom wall 176 beneath guide block 200. Spring 250
provides a safety lockout feature by lifting knife support bar cut
out 224 against guide block 200 after firing, to prevent re-firing
of a used cartridge. A second spring 252 is integrated into module
pan bottom wall 176 near the proximal end of the pan. This second
spring 252 is a detent spring that interacts with a notch on pusher
block 180 to prevent forward movement of actuator knob 182 during
shipping, and to provide audible and tactile feedback when the
actuator knob is returned to the proximal-most position in the
module pan following firing. FIGS. 28 and 29 illustrate the
operation of detent spring 252 in greater detail. In FIG. 28,
spring 252 is shown engaging a notch 254 on pusher block 180 to
prevent unintentional distal movement of the pusher block. FIG. 29
shows detent spring 252 disengaged from notch 254 by the
application of an intentional, distally directed force on actuator
knob 182. Pusher bars 190 and knife support bar 214 are advanced
distally by applying sufficient force to actuator knob 182 to
overcome the force of spring 252 against notch 254. After spring
252 is disengaged from notch 254, pusher block 180 can slide
distally through module pan 172 to first advance pusher bars 190
and then advance knife support bar 214 from guide block 200 into
staple cartridge 90.
[0057] In an initial firing position, shown in FIG. 28, a
downwardly directed edge of pusher block 180 is in contact with
knife support bar 214 at the proximal end point 232 of offset
section 226. Actuating knob 182 is retracted to a fully proximal
position within guide slot 186, thereby placing pusher bars 190 and
knife blade 222 within slots 194 and 220 of guide block 200. When a
distal pushing force is applied to actuating knob 182, spring 252
disengages from notch 254, enabling pusher block 180 to advance
longitudinally within module pan 172. As pusher block 180 moves,
the block advances pusher bars 190 distally, causing the inclined
tips of the bars to advance into cartridge driver slots 100. During
the initial movement of pusher block 180, the distal edge of the
block moves through knife support bar offset 226, as shown in FIG.
29, thereby not making contact with the support bar itself. Knife
support bar 214 thus remains stationary during the initial distal
movement of the pusher bars 190 and block 180.
[0058] After pusher block 180 advances through knife offset section
226, the distal edge of the block contacts the distal end point 230
of knife support bar 214. This contact between pusher block 180 and
knife support bar 214 causes the knife support bar to begin
advancing distally, along with the pusher block and pusher bars
190, as knob 182 is advanced. As knife support bar 214 moves
distally, knife blade 222 is guided by central slot 220 and rear
cartridge extension 116 into central longitudinal slot 94 of staple
cartridge 90 and central longitudinal slot 46 of anvil 44. As knife
blade 222 advances through cartridge extension 116, the blade
deflects lock out pin 106 out of the path of the advancing support
bar. Knife blade 222 and pusher bar tips 206 advance simultaneously
through staple cartridge 90 driving staples through openings 96 and
cutting tissue. Knife blade 222 is advanced into staple cartridge
90 slightly behind pusher bars 190 so that staples are formed into
the tissue gripped between the anvil and cartridge prior to the
knife blade advancing and cutting the tissue between the staple
rows.
[0059] After the knife and pusher bars have been fully advanced by
knob 182 (or advanced to the desired forward position), pusher
block 180 is retracted within module pan 172 by drawing the
actuating knob back proximally through jaw guide slot 186.
Initially, as pusher block 180 is drawn proximally, pusher bars 190
are drawn proximally while knife support bar 214 remains in a
distal, stationary position due to the offset section 226 in the
support bar. As the distal pusher block edge retracts into contact
with proximal knife bar offset point 232, the knife support bar 214
begins to retract proximally with the pusher block and bars. As
knife support bar 214 retracts within guide block 200, the support
bar is lifted up by leaf spring 250 into contact with the guide
block, until the knife locking cut out 224 catches a center post
256 (FIG. 23) of the guide block. Once knife cut out 224 engages
guide block post 256, knife support bar 214 is prevented from
further movement in conjunction with pusher block 180. Preferably,
knife support bar 214 engages locking cut out section 224 as pusher
block 180 and pusher bars 190 are reaching the fully proximal
position.
[0060] After actuator knob 182 is fully retracted, as shown in FIG.
28, latching member 30 is pivoted relative to jaw members 22, 24 to
separate the upper and lower jaws, as described above. With the jaw
members separated, staple cartridge 90 can be removed and replaced
with a new cartridge. The used cartridge can be removed by pulling
up on cartridge wings 114 to dislodge cartridge legs 110 from lower
jaw opening 76. As the proximal end of the staple cartridge is
lifted out of lower jaw opening 76, cartridge leg notches 112 (FIG.
7) are drawn out of engagement with latch pin 122. After the
proximal end of staple cartridge 90 is dislodged, the cartridge can
be slid distally out of cartridge channel 70 and discarded.
[0061] A new staple cartridge 90 can be loaded into lower jaw 24 by
pushing the flanged, distal end of the cartridge against the distal
end of the lower jaw cartridge channel 70, and pushing down on
wings 114 to lower legs 110 through jaw opening 76. Cartridge legs
110 are pushed through lower jaw opening 76 until leg notches 112
snap onto latch pin 122. As the proximal end of staple cartridge 90
is pushed down, lockout pin 106 on the cartridge depresses knife
support bar 214 at locking notch 228 against the counter force of
leaf spring 250. The force of lockout pin 106 pushes knife support
bar cutout 224 down and out of contact with guide block center post
256. As knife support bar 214 is pushed down, the support bar is
realigned with guide block center slot 220 to enable the support
bar to pass distally through the slot and into the new cartridge.
The safety lockout feature is thus reset during loading of a new
staple cartridge. With a new cartridge loaded, the stapler can be
reassembled by placing upper jaw 22 over lower jaw 24 and
reinserting upper jaw pins 54 into lower jaw alignment slots 56.
Latching hook members 140 are pivoted back over the opening of
slots 56 until pins 54 are lodged within notches 142. With pins 54
locked within hook member notches 142, and latching member 30
pivoted into position about lower jaw 24, the stapler is closed and
ready to fire staples from the new cartridge.
[0062] The reusable upper and lower jaw and latching member
components described above are provided to a user in a non-sterile
package. Prior to assembly of stapler 20, the components are
cleaned with pH neutral enzymatic cleaners, and then steam
autoclaved to sterilize the components. This conditioning procedure
is also followed prior to each subsequent reuse of the components.
Actuator module 170, due to it multiple movable components, is
designed for single patient use to eliminate the complexity of
cleaning the module. The actuator module is provided to the user in
a sterile disposable package which is opened in the sterile field.
Staple cartridge 90 is also delivered as a sterile disposable
package that is opened in the sterile field.
[0063] To assemble stapler 20, actuator module 170 is removed from
its packaging and inserted proximal end first into the proximal
channel of lower jaw member 24. Actuator module 170 snaps into
place when proximal detent bumps 178 engage lower jaw retention
features 86. The distal end of the actuator module is then rotated
down into the channel shaped frame of lower jaw 24. With actuator
module 170 within the lower jaw channel, protector cap 234 is
pushed down to snap cap lips 240 into indentations 74 on the lower
jaw sidewalls 64a, 64b. Pushing down on protector cap 234 pushes
guide block center section 212 through lower jaw opening 76,
aligning guide block slot 212 with lower jaw slot 82, and locking
the actuator module in place within the lower jaw member 24. With
actuator module 170 loaded into lower jaw member 24, latching
member 30 is attached to the lower jaw by inserting latch pin 122
into slots 82 and 212, as described above. Latching member 30 is
rotated relative to lower jaw member 24 to the partial locked-in
position shown in FIG. 14. In this position, latching member 30 is
attached to lower jaw member 24, but upper jaw 22 is separable from
the lower jaw. Protector cap 234 is removed from actuator module
170 by moving the cap in the distal direction, as indicated by the
arrow on the cap shown in the Figures.
[0064] A new staple cartridge 90 is next inserted into lower jaw
cartridge channel 70 in the manner described above. After a staple
cartridge is loaded, upper jaw member 22 is placed over lower jaw
member 24, with pins 54 inserted into alignment slots 56. Latching
member 30 is pivoted relative to the upper and lower jaw members
22, 24 to place the stapler into the pre-close position (shown in
FIG. 15), in which the hook member cam surfaces 144 extend over the
openings to alignment slots 56 to prevent pins 54 from disengaging
from the slots. The tissue to be transected is placed between the
anvil 44 and staple cartridge 90 and adjusted to the desired
position. Tissue stops 52 prevent the tissue from being positioned
too far back into the stapler. With the tissue properly situated,
the stapler is closed in preparation for firing by rotating
latching member 30 into contact with lower jaw 24 to place hook
member 140 over slots 56, and lock pins 54 inside hook member
notches 142. In this state, the tissue is clamped within the
device. If additional tissue adjustment is required, the stapler
can be returned to the pre-close state, as shown in FIG. 16, in
which the distal ends of the upper and lower jaw members can move
slightly relative to each other to accommodate tissue
repositioning. With the tissue properly clamped between the jaw
members, and latching member 30 pivoted to the closed, operative
position, the stapler can be fired by pushing actuator knob 182
forward through guide slot 186 until the knob stops. As the knob
advances, the clamped tissue is stapled and cut. After actuator
knob 182 reaches its distal stop, the knob is drawn back proximally
through guide slot 186. At the proximal end of the knob path, the
interaction of detent spring 252 and push block notch 254 provides
tactile and audible feedback that the knob is fully retracted,
signaling that the actuating components have been withdrawn from
staple cartridge 90 back into module pan 172.
[0065] If additional stapling and cutting is desired to complete
the procedure, latching member 30 is pivoted back to the partially
locked-in state so that upper jaw 22 can be removed, and the used
staple cartridge discarded and replaced with a new staple
cartridge. After the new cartridge is in place, latching member 30
can be pivoted back through the pre-close and closed states to
enable tissue to again be positioned, clamped and stapled using the
new cartridge. Once all the required tissue is transected, latching
member 30 is removed by rotating the member back to the open state
(shown in FIG. 13), and sliding latch pin 122 out of slots 82 and
212. The actuating module 170 and staple cartridge 90 can then be
removed from lower jaw member 24 and discarded. The remaining
components (upper jaw, lower jaw, and latching member) can be
cleaned and sterilized as separate components in preparation for
reuse.
[0066] In the present invention, actuator module 170 is a separate
component from staple cartridge 90, enabling spent staple
cartridges to be replaced during a single patient procedure without
replacing the actuator module. Accordingly, the actuator module may
be used multiple times in the same patient with different staple
cartridges. Using the single piece module pan 172 as a supporting
structure for the actuator module components enables the actuator
module to be easily assembled into and disassembled from the lower
jaw channel. The reusable stapler components have a simple, single
piece design to facilitate repeated reconditioning and reuse of the
parts. The detachable design of the latching member facilitates
easy disassembly and reassembly of the reusable components of the
stapler. Further, once the stapler is assembled, the retaining and
locking features of the latching and lower jaw members prevent
accidental disassembly during a procedure.
[0067] The foregoing description of a preferred embodiment of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed. Obvious modifications or
variations are possible in light of the above teachings. The
embodiment was chosen and described in order to best illustrate the
principles of the invention and its practical application to
thereby enable one of ordinary skill in the art to best utilize the
invention in various embodiments and with various modifications as
are suited to the particular use contemplated. It is intended that
the scope of the invention be defined by the claims appended
hereto.
* * * * *