Pin locking mechanism for a surgical instrument

A surgical instrument comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and first and second jaw members dimensioned to clamp tissue therebetween. The first jaw member has at least one row of fasteners arranged in a row substantially transverse to the longitudinal axis. A pin is disposed in mechanical cooperation with the first jaw member and is movable between a first position where the engagement section is spaced from the second jaw member and a second position where the engagement section engages the second jaw member. The pin has a non-circular cross-section.

BACKGROUND

1. Technical Field

The present disclosure relates generally to a surgical instrument and, more specifically, to a surgical instrument for clamping, severing, and joining tissue.

2. Background of Related Art

Certain surgical stapling instruments are used for applying rows of staples through compressed living tissue. These surgical stapling instruments are employed, for example, for fastening tissue or organs prior to transection or resection or during anastomoses. In some cases, these surgical stapling instruments are utilized for occluding organs in thoracic and abdominal procedures.

Typically, such surgical stapling instruments include an anvil assembly, a cartridge assembly for supporting an array of surgical staples, an approximation mechanism for approximating the cartridge and anvil assemblies, an alignment or guide pin assembly for capturing tissue between the cartridge and anvil assemblies and for maintaining alignment between the cartridge and anvil assemblies during approximation and firing, and a firing mechanism for ejecting the surgical staples from the cartridge assembly.

In use, the alignment pin assembly is advanced and the anvil and cartridge assemblies are approximated. Next, the surgeon tires the instrument to place staples in tissue. Optionally, the surgeon may use the same instrument or a separate device to cut the tissue adjacent or between the row(s) of staples. The alignment pin in some instances is advanced automatically with approximation of the cartridge; in other instances it is advanced by a separate mechanism.

SUMMARY

The present disclosure provides a surgical instrument comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and an end effector disposed adjacent a distal portion of the elongated portion including a first jaw member and a second jaw member dimensioned to clamp tissue therebetween.

A pin is disposed in mechanical cooperation with the first jaw member and includes an engagement section and is movable between a first position wherein the engagement section is spaced from the second jaw member and a second position wherein the engagement section engages the second jaw member. The pin has a non-circular cross-section.

Preferably, a knife is provided to move distally to cut the clamped tissue. Preferably, the knife has an upper edge terminating alongside the pin. In one embodiment, the pin has a gap dimensioned to accommodate the knife. The instrument can include rows of fasteners with the knife positioned between the rows.

In one embodiment, the pin is substantially semi-circular in cross-section. In another embodiment the pin is substantially L-shaped in cross-section.

The instrument can include a second non-circular pin. In one embodiment, the pins are spaced from each other and one pin is adjacent a top portion of a knife and the other pin is positioned adjacent a bottom portion of the knife. The pins can be positioned on opposite sides of a knife slot from which the knife extends.

In some embodiments, the instrument can further include a second pin having a substantially semi-circular cross section, each of the pins having a substantially planar surface, the substantially planar surface of the second pin facing a direction opposite the direction the substantially planar surface the other pin faces.

The pins in some embodiments can move in a distal direction automatically when the first and second jaw members move to a position to clamp tissue.

In another aspect, a surgical instrument is provided comprising a handle portion, an elongated portion defining a longitudinal axis and extending distally from the handle portion, and an end effector disposed adjacent a distal portion of the elongated portion. The end effector included a first jaw member and a second jaw member, the first and second jaw members dimensioned to clamp tissue therebetween. The first jaw member has at least one row of fasteners arranged in a row substantially transverse to the longitudinal axis. A pin is disposed in mechanical cooperation with the first jaw member and includes an engagement section, the pin movable between a first position wherein the engagement section is spaced from the second jaw member and a second position wherein the engagement section engages the second jaw member. A second pin is spaced from the first pin, the first pin and second pin each having a surface alongside the knife wherein the first surface of the first pin faces in a first direction and the second surface of the second pin faces in a second opposite direction.

In some embodiments, the first and second surfaces of the pins are substantially planar. The first pin can have a third surface facing toward a top surface of the knife and the second pin can have a fourth surface facing towards the bottom surface of the knife. In some embodiments, the pins move in a distal direction automatically when the first and second jaw members move to a position to clamp tissue.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments of the presently disclosed surgical stapling instrument are described in detail with reference to the drawings, wherein like reference numerals designate corresponding elements in each of the several views. In the description that follows, the term “proximal” refers to the end or portion of the surgical stapling instrument closer to the user, whereas the term “distal” refers to the end or portion of the surgical stapling instrument further from the user.

In the interest of brevity, the present disclosure focuses on the pin for a surgical stapling instrument designated in the drawings by reference numeral100. U.S. Pat. No. 7,407,076, the entire contents of which are incorporated by reference herein, describes in detail the structure and operation of an embodiment of surgical stapling instrument100.

FIG. 1illustrates a surgical stapling instrument100designed for applying fasteners and cutting tissue. In brief, surgical stapling instrument100includes a handle portion110, an elongate portion120, and an end effector130extending from the distal portion of the elongate portion120. Handle portion110contains a trigger140for actuating end effector130. Elongate portion120extends distally from handle portion110and defines a longitudinal axis A-A therealong. End effector130is disposed adjacent to a distal portion of elongate portion120and includes a first jaw member or cartridge assembly150and a second jaw member or anvil assembly160. In this embodiment, cartridge assembly150is adapted to move longitudinally with respect to anvil assembly160upon actuation of trigger140to clamp tissue between the jaw members150,160. It is also contemplated that the anvil assembly can be moved (approximated) toward the cartridge assembly or that the cartridge and anvil assemblies can both be moved toward each other to clamp tissue.

Cartridge assembly150includes a plurality of slots152(FIGS. 1B and 1C) each capable of holding a staple or any other suitable fastener. Each slot152is operatively associated with a pusher thrust bar or plunger122. Pusher122extends along elongate portion120and partially into cartridge assembly150. Cartridge assembly150also includes a knife advanceable to cut tissue clamped between the cartridge and anvil assemblies150,160, respectively. In use, pusher122moves distally upon actuation of trigger140and causes the ejection of the staples disposed in slots152in a distal direction, substantially parallel to the longitudinal axis of the elongate portion120. In addition to slots152, cartridge assembly150includes a pin154operatively connected to pusher122and a bore156dimensioned to slidably receive pin154. Pin154is adapted to move longitudinally along bore156in response to a translation of pusher122. The pin154can alternatively be moved by a sliding knob155in the handle portion110. In the embodiment depicted inFIG. 1A-1C, anvil assembly160has a hole162designed to receive at least a portion of pin154. Anvil assembly160has staple-deforming pockets164for deforming the fasteners ejected from cartridge assembly150. An elongated slot can be provided between the pockets164in the anvil assembly to accommodate the knife described below.

While anvil assembly160remains stationary with respect to cartridge assembly150during operation, cartridge assembly150is movable longitudinally between a proximal position and a distal position upon actuation of trigger140. In the proximal position, cartridge assembly150is spaced apart from anvil assembly160, as seen inFIG. 1Bin an approximated position. The actuation of trigger140causes clamp slides170, operatively connected thereto, to move distally which in turn causes thrust bar122to move distally due to pins174. In turn, the distal translation of thrust bar122causes the distal movement of cartridge assembly150toward anvil assembly160to an approximated position. While cartridge assembly150moves from the proximal position toward the distal position, end effector130clamps any tissue placed between cartridge assembly150and anvil assembly160as shown inFIG. 1C. In the distal position, cartridge assembly150is located closer to anvil assembly160and presses tissue “T” against anvil assembly160.

Further actuation of trigger140, i.e. a second squeeze of the trigger140, once cartridge assembly150reaches its distal (approximated) position causes ejection of the fasteners from slots152. That is, the continued distal translation of pusher122, once cartridge assembly150is located in the distal position, causes the deployment of the fasteners positioned in slots152. During deployment, these fasteners exit slots152and advance through tissue and into contact with staple-deforming pockets164of anvil assembly160for formation thereof, e.g. bending of the staple legs into a “B” configuration. Actuation of trigger140also advances the knife to sever tissue clamped between the cartridge and anvil jaw assemblies150,160.

Note the distal motion of clamp slides170causes alignment pin154to move distally along bore156due to the operative connection of the alignment pin pusher172to the clamp slides170via pins extending through elongated slots in pin pusher172as described in U.S. Pat. No. 7,407,076. (Pin pusher172includes a vertical portion having an abutment member configured to engage the proximal end of the pin154.) Upon sufficient distal movement of pin154, hole162of anvil assembly160receives a portion of pin154. The structural interaction between pin154and hole162(when cartridge assembly150is located in the distal position) assists in the alignment of slots152with staple-deforming pockets164. It should be appreciated that alignment pin154can alternatively be moved manually as pin pusher172is moved manually, e.g. by sliding knob155.

Turning now to embodiments of the alignment pins of the present disclosure illustrated inFIGS. 2-7, these pins can be used with the stapler ofFIG. 1described above or with other suitable surgical staplers. They can be configured to move automatically with approximation of the cartridge, i.e. in response to actuation of the trigger, and/or moved by the user separate from approximation, e.g. by an independent slidable knob or other manual controls or knobs located at various portions of the instrument. Thus, it should be understood that it is contemplated that the pins disclosed herein can be moved in either way (automatic or manual) or in both ways.

FIGS. 2 and 3illustrate a close up view of the cartridge assembly150ofFIG. 1. In this embodiment, cartridge assembly150includes a plurality of staple slots132and a knife slot134. Each staple slot132houses a staple or fastener136. Knife slot134is adapted to receive knife138. Knife138is configured to move longitudinally to cut tissue between the staple rows. Preferably, knife138is advanced distally when the staples are advanced from cartridge assembly150through tissue. In this embodiment, two rows of staples are provided, extending substantially linearly and substantially transverse to longitudinal axis A-A of the instrument100. A different number of staples and staple rows are also contemplated.

Cartridge assembly150further includes a bore156configured to receive a pin154. Pin154is adapted to move longitudinally between a proximal position and a distal position and has a substantially semi-circular cross-section to allow passage of knife138adjacent the pin154. That is, the knife138passes by (alongside) the substantially planar inner surface region of the pin154. The substantially semi-circular shape of pin154allows the knife138to extend up to the region of the pin154. As shown, the knife134extends past the bottom154aof the pin154and terminates adjacent an intermediate region154bof the pin154. Other knife heights are also contemplated. The staple slots156and staple line extend beyond the top edge138aof the knife138and beyond the bottom edge138bof the knife138.

FIG. 4illustrates an alternate embodiment of the cartridge assembly, designated generally by reference numeral250. Cartridge assembly is substantially identical to cartridge assembly150ofFIG. 2, except that four rows of staples are provided. As shown, the four substantially linear rows of staples236are arranged substantially transverse to the longitudinal axis A-A of the instrument, with two staggered rows positioned on either side of knife238. As in the other embodiments herein, the staples236are fired in a direction substantially parallel to the longitudinal axis of the instrument. The knife238is movable from knife slot234to sever tissue clamped between the cartridge and anvil assemblies. Pin254is substantially semi-circular shaped, similar to pin154. The staples236extend beyond the upper and lower edges238a,238b, respectively, of knife238.

In the alternate embodiment ofFIG. 5, cartridge assembly, designated generally by reference numeral350, is substantially identical to cartridge assembly150ofFIG. 2, except for the configuration of pin354. As shown, two substantially linear rows of staples236are arranged substantially transverse to the longitudinal axis of the instrument, with one row positioned on either side of knife338. A different number of rows are also contemplated. The knife338is movable from knife slot334to sever tissue clamped between the cartridge and anvil assemblies. The staples336extend beyond the upper and lower edges338a,338b, respectively, of knife338. Pin354is substantially L-shaped in configuration to create a gap357to accommodate the knife. That is, portion354aextends downwardly alongside the knife338and portion354bextends transversely above the upper edge338aof knife338. Consequently, the pin354extends in an arc of about 270 degrees (although other arcs are also contemplated).

It should be appreciated that although one alignment pin is shown, it is also contemplated that two alignment pins can be provided, e.g. one on the upper portion of the cartridge and the other on the lower portion of the cartridge. This is shown for example in the embodiment ofFIG. 7, wherein upper pin454and lower pin455are provided in cartridge450. Each of the pins454,455are substantially semi-circular in configuration, similar to pin254ofFIG. 2, however the substantially L-shaped pins ofFIG. 5could also be provided (either one at the top or bottom utilized with the substantially semi-circular pin on the opposing end or on both the top and bottom.) Note that the pins454,455are preferably on opposing sides of the knife438. As in the other embodiments, the staple line extends beyond the upper edge438aand lower edge438bof knife438.

While the above description contains many specifics, these specifics should not be construed as limitations on the scope of the present disclosure, but merely as illustrations of various embodiments thereof. Therefore, the above description should not be construed as limiting, but merely as exemplifications of various embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.