Patent Description:
Surgical staplers are used to approximate or clamp tissue and to staple the clamped tissue together. As such, surgical staplers have mechanisms to ensure that tissue is properly positioned and captured and to drive staples through the tissue. As a result, this has produced, for example, multiple triggers and handles in conjunction with complex mechanisms to provide proper stapling of the clamped tissue. With these complex mechanisms, surgical staplers can have increased manufacturing burdens, as well as potential sources for device failure and confusion for the user. Thus, reliable stapling of clamped tissue without complex mechanisms is desired. Examples of known surgical staplers are disclosed in US patent applications, publication numbers <CIT> and <CIT>.

According to the present invention there is provided a surgical stapler as recited in Claim <NUM>. Preferred embodiments are recited in the dependent claims.

With reference to <FIG>, an embodiment of surgical stapling device is illustrated. The illustrated embodiment of surgical stapler <NUM> comprises an elongate shaft <NUM>, a jaw assembly <NUM>, and a handle assembly <NUM>. <FIG> illustrates the surgical stapler <NUM> with the jaw assembly <NUM> in an open configuration. <FIG> illustrates a removable cartridge comprising the elongate shaft <NUM> and jaw assembly <NUM> of the surgical stapler <NUM> with the jaw assembly <NUM> in a closed configuration.

With continued reference to <FIG> and <FIG>, the illustrated embodiment of surgical stapler <NUM> can be sized and configured for use in laparoscopic surgical procedures. For example, the elongate shaft <NUM> and jaw assembly <NUM> can be sized and configured to be introduced into a surgical field through an access port or trocar cannula. In some embodiments, the elongate shaft <NUM> and jaw assembly <NUM> can be sized and configured to be inserted through a trocar cannula having a relatively small working channel diameter, such as, for example, less than <NUM>. In other embodiments, elongate shaft <NUM> and jaw assembly <NUM> can be sized and configured to be inserted through a trocar cannula having a larger working channel diameter, such as, for example, <NUM>, <NUM>, <NUM>, or <NUM>. In other embodiments, it is contemplated that certain aspects of the surgical staplers described herein can be incorporated into a surgical stapling device for use in open surgical procedures.

With continued reference to <FIG> and <FIG>, as illustrated, the elongate shaft <NUM> comprises a generally tubular member. The elongate shaft <NUM> extends from a proximal end <NUM> to a distal end <NUM>. Elongate shaft <NUM> defines a central longitudinal axis, L. of the surgical stapler <NUM> extending between the proximal end <NUM> and the distal end <NUM>.

With continued reference to <FIG> and <FIG>, in the illustrated embodiment, the jaw assembly <NUM> is coupled to the elongate shaft <NUM> at the distal end <NUM> of the elongate shaft <NUM>. The jaw assembly <NUM> comprises a first jaw <NUM> and a second jaw <NUM> pivotally coupled to the first jaw <NUM>. In the illustrated embodiment, the first jaw <NUM> is fixed to the distal end <NUM> of elongate shaft <NUM> such that it extends distally along the central longitudinal axis, L and remains stationary with respect to the elongate shaft <NUM>. In other embodiments, it is contemplated that both the first and second jaws <NUM>, <NUM> are pivotable with respect to the elongate shaft. In other embodiments, it is contemplated that the jaw assembly <NUM> is articulable with respect to the elongate shaft <NUM>. In an initial configuration, the first jaw <NUM> includes a plurality of staples <NUM> disposed therein. In some embodiments, staples can be initially positioned in the second jaw <NUM>.

With continued reference to <FIG> and <FIG>, in the illustrated embodiment, the jaw assembly <NUM> can be actuated from an open configuration (<FIG>) to a closed configuration (<FIG>) to a stapling configuration by an actuation member or beam that is longitudinally slideable within the elongate shaft. In an initial position, the beam can be positioned at the distal end <NUM> of the elongate shaft <NUM>. With the beam in the initial position, the second jaw <NUM> is pivoted away from the first jaw <NUM> such that the jaw assembly <NUM> is in the open configuration. The actuation beam engages the second jaw <NUM> upon translation of the actuation member or beam distally along the longitudinal axis L. Translation of the actuation beam distally from the initial position a first distance can actuate the jaw assembly from the open configuration to the closed configuration. With the jaw assembly <NUM> in the closed configuration, the actuation beam can be returned proximally the first distance to return the jaw assembly <NUM> to the open configuration. A distal end of the actuation beam can advance a staple slider configured to deploy staples from the first jaw <NUM> such that further translation of the actuation beam distally past the first distance deploys the plurality of staples <NUM> from the first jaw <NUM>.

With continued reference to <FIG> and <FIG>, in the illustrated embodiment, the handle assembly is coupled to the elongate shaft <NUM> at the proximal end <NUM> of the elongate shaft <NUM>. As illustrated, the handle assembly <NUM> has a pistol grip configuration with a housing defining a stationary handle <NUM> and an actuator such as a movable handle <NUM> or trigger pivotably coupled to the stationary handle <NUM>. It is contemplated that in other embodiments, surgical stapler devices including aspects described herein can have handle assemblies with other configurations such as, for example, scissors-grip configurations, or in-line configurations. As further described in greater detail below, the handle assembly <NUM> houses an actuation mechanism configured to selectively advance an actuation shaft responsive to movement of the movable handle <NUM>. In some embodiments, the actuation mechanism can comprise a powered actuation mechanism such as an electric motor that can be actuated to selectively advance an actuation shaft. Actuation of the electric motor can be initiated through movement of the movable handle <NUM> or actuation of a trigger, button, switch, or another actuator electrically operably coupled to the electric motor of the powered actuation mechanism.

In some embodiments, the surgical stapler <NUM> can include the plurality of staples <NUM> positioned in a disposable cartridge while the handle assembly <NUM> is configured to be reused with multiple staple cartridges. In the illustrated embodiment, the elongate shaft <NUM> and jaw assembly <NUM> define a disposable cartridge that is removably couplable to the handle assembly <NUM>. Accordingly, in the illustrated embodiment the handle assembly <NUM> includes a coupler <NUM> at the distal end thereof. The coupler <NUM> is adapted to engage the elongate shaft <NUM> of the surgical stapler <NUM> The coupler <NUM> can have a bayonet connection having an outer connector that can removably couple the handle assembly <NUM> to the elongate shaft <NUM>, and an inner connector that can removably couple the actuation shaft of the handle assembly <NUM> to the actuation member of the elongate shaft <NUM>. Accordingly, the surgical stapler <NUM> can be configured such that the handle assembly <NUM> can be reused with multiple disposable cartridges during a surgical procedure. It is contemplated that in other embodiments, the handle assembly and some portion of the elongate shaft can be reusable while a remainder of the elongate shaft and the jaw assembly define a disposable cartridge. In certain other embodiments, the handle assembly and the elongate shaft can be reusable while the jaw assembly defines a disposable cartridge. In still other embodiments, a jaw insert housing a plurality of staples can define a disposable cartridge while the remainder of the surgical stapler is reasonable.

<FIG> illustrate various views of an embodiment of handle assembly <NUM> for a surgical stapler <NUM>. In <FIG>, a perspective view of the handle assembly <NUM> as illustrated with the movable handle <NUM> in an open position spaced apart from the stationary handle <NUM>. The illustrated handle assembly <NUM> further comprises a selector <NUM> operably coupled to the actuation mechanism housed within the handle assembly <NUM> as further discussed herein. As illustrated in <FIG>, the selector <NUM> is in a first position.

With reference to <FIG>, another perspective view of the handle assembly <NUM> of <FIG> is illustrated. As illustrated, the movable handle <NUM> is in a closed position positioned adjacent the stationary handle <NUM>, and the selector <NUM> is in a second position. <FIG> illustrate a top view of the handle assembly of <FIG> with the selector <NUM>, such as a slider <NUM>, in the first position (<FIG>), and in the second position (<FIG>). <FIG> illustrates a side view of the handle assembly <NUM> of <FIG>.

<FIG> illustrate cross-sectional views of the handle assembly <NUM> in an initial configuration, revealing operation of the actuation mechanism <NUM>. In the illustrated embodiment, the actuation mechanism <NUM> is configured to selectively translate the actuation shaft <NUM> from a first position corresponding to the jaw assembly <NUM> being in the open configuration to a second position corresponding to the jaw assembly <NUM> being in the closed configuration and from the second position to a third position to position the jaw assembly <NUM> in a stapling configuration and deploy the plurality of staples <NUM>. In the initial configuration illustrated in <FIG>, actuation mechanism <NUM> can repeatedly translate the actuation shaft <NUM> between the first position and the second position responsive to movement of the movable handle <NUM> or trigger without deploying the staples to provide an open and close functionality. This open and close functionality allows a user to position, clamp tissue, and reposition the stapler <NUM> to find a desirable staple placement location before deploying the staples.

With reference to <FIG>, in the illustrated embodiment, the actuation mechanism comprises an advancing or forward driver <NUM>, a reverse driver <NUM>, a opening driver <NUM>, an advancing surface <NUM>, a reversing surface <NUM>, and a opening surface <NUM>. The forward driver <NUM> can be operably coupled to the movable handle <NUM> such that movement of the movable handle <NUM> from the open position to the closed position advances the forward driver <NUM> in a first direction such as for example distally within the handle assembly <NUM>. The forward driver <NUM> can comprise a pawl or tooth configured to engage a recess or slot.

The reverse driver <NUM> can be operably coupled to movable handle <NUM> such that movement of the movable handle <NUM> from the open position to the closed position advances the reverse driver <NUM> in a second direction opposite the first direction such as, for example proximally within the handle assembly <NUM>. In some embodiments, the movable handle <NUM> can be operably coupled with the reverse driver <NUM> with a geared connection including an idler gear <NUM>. The reverse driver <NUM> can comprise a pawl or tooth configured to engage a recess or slot.

The opening driver <NUM> can be operably coupled to the movable handle <NUM> such that movement of the movable handle <NUM> from the open position to the closed position advances the opening driver <NUM> in a first direction such as for example distally within the handle assembly <NUM>. In the illustrated embodiment, the opening driver <NUM> is coupled to the idler <NUM> with a pin and slot connection to operably couple the opening driver <NUM> to the movable handle <NUM>. The opening driver <NUM> can comprise a pawl or tooth configured to engage a recess or slot.

The actuation shaft <NUM> includes advancing surface <NUM>, reversing surface <NUM>, and opening surface <NUM> formed thereon. In the illustrated embodiment, the advancing surface <NUM> comprises a rack, or plurality of spaced recesses or teeth formed longitudinally along the actuation shaft <NUM>. As illustrated, reversing surface <NUM> comprises a rack or plurality of space recesses or teeth formed longitudinally along the actuation shaft <NUM> and angularly offset from the advancing surface <NUM>. In the illustrated embodiment, the opening surface <NUM> comprises a recess formed in the actuation shaft <NUM>.

In certain embodiments, the actuation shaft <NUM> is rotatable within the handle assembly <NUM> about the longitudinal axis of the stapler <NUM>. The actuation shaft <NUM> can comprise a proximal portion <NUM> and a distal portion <NUM> that are independently rotatable with respect to one another. For example, the proximal portion <NUM> can be coupled to the distal portion <NUM> at a rotatable coupling that allows free rotation therebetween while coupling the proximal portion to the distal portion with respect to longitudinal translation. The handle assembly <NUM> can comprise a rotation mechanism <NUM> to provide selective rotation of the proximal portion <NUM> of the actuation shaft <NUM> within the handle assembly <NUM>. The actuation shaft <NUM> can be rotatable between a first orientation in which the forward driver <NUM> is engageable with the advancing surface <NUM> and a second orientation in which the reverse driver <NUM> is engageable with the reversing surface <NUM>. With the angular offset of the advancing surface <NUM> from the reversing surface <NUM> with respect to the actuation shaft <NUM>, with the actuation shaft in the first orientation, the reverse driver <NUM> is disengaged from the reversing surface <NUM>, and with the actuation shaft in the second orientation, the forward driver <NUM> is disengaged from the advancing surface <NUM>.

With continued reference to <FIG>, in certain embodiments, the rotation mechanism <NUM> comprises a selector <NUM>, such as a slider. The slider can extend transversely through the housing of the handle assembly <NUM>. The slider can be operably coupled to the actuation shaft <NUM> such that positioning the slider in the first position extending from one side of the handle assembly <NUM> positions the actuation shaft <NUM> in the first orientation, and positioning the slider in the second position extending from an opposite side of the handle assembly <NUM> rotates the actuation shaft <NUM> to the second orientation. In the illustrated embodiment, the slider is coupled to a rack <NUM> in meshing engagement with a gear <NUM> that is rotatably fixed to the actuation shaft <NUM> and longitudinally slideable along the actuation shaft <NUM> (such as, for example, with a keyed connection). Desirably, the illustrated rotation mechanism <NUM> including a slider discretely positions the actuation shaft <NUM> in a desired orientation, reducing the incidence of the mismeshed gearing within the actuation mechanism <NUM>. In some embodiments the slider can include visual indicators, such as arrows, to indicate the orientation of the actuation shaft <NUM>, and thus, the actuation mode of the stapler to a user.

In the illustrated embodiment, the advancing surface <NUM> and the reverse surface <NUM> are angularly offset by approximately <NUM> degrees about the actuation shaft. Thus, the rotation mechanism <NUM> is configured to rotate the actuation shaft approximately <NUM> degrees between the first orientation and the second orientation. In other embodiments, the actuation surface <NUM> and the reverse surface <NUM> can have a different angular offset, such as, for example <NUM> degrees or <NUM> degrees, and the rotation mechanism <NUM> can be configured to rotate the actuation shaft <NUM> correspondingly. Moreover, as described in further detail herein with respect to an open/close mode of the handle assembly <NUM> operation, in the illustrated embodiment, the opening driver <NUM> engages with the actuation shaft in the second orientation, in other embodiments, the actuation shaft can be rotatable to a third orientation in which the opening driver <NUM> engages with the actuation shaft.

With reference to <FIG>, a typical operation sequence of the actuation mechanism <NUM> of the handle assembly <NUM> is illustrated. <FIG> and 9A-9B illustrate operation of the handle assembly <NUM> in an initial configuration providing an open/close functionality to the jaw assembly <NUM>. In <FIG>, the movable trigger <NUM> is at an open position, and the actuation shaft <NUM> is at a first position, corresponding to the first position of the actuation beam at the distal end of the elongate shaft <NUM>. In the initial position, the actuation shaft <NUM> is positioned at the second orientation such that the reverse driver <NUM> is angularly aligned with the reversing surface <NUM>. With actuation shaft <NUM> in the second orientation, the opening driver <NUM> is positioned within the opening surface <NUM> or recess. Movement of the movable handle <NUM> from the open position (<FIG>) to the closed position (<FIG>), advances the forward driver <NUM> distally along the actuation shaft <NUM> to engage an advancing recess <NUM> formed in the actuation shaft <NUM> and drive the actuation shaft <NUM> distally in the handle assembly <NUM> to a second position. The second position of the actuation shaft <NUM> within the handle assembly <NUM> corresponds to the second position of the actuation beam, which positions the jaw assembly <NUM> in a closed configuration.

The movable handle <NUM> can be biased to the open position by a biasing member, such as a coil spring <NUM> (<FIG>). Thus, releasing the movable handle <NUM> from the closed position illustrated in <FIG> would return it to the open position of <FIG>. Operable coupling of the movable handle <NUM> to the opening driver <NUM> would likewise translate the opening driver <NUM> proximally within the handle assembly <NUM> as the movable handle <NUM> returns to the open position. In the second orientation of the actuation shaft <NUM>, the opening driver <NUM> engages opening surface <NUM> such that the proximal movement of the opening driver <NUM> returns the actuation shaft <NUM> from the second position to the first position, returning the jaw assembly <NUM> to the open configuration.

A user can seek a desired stapling position within a surgical field by repeatedly opening and closing the jaws to clamp tissue in various locations. Once a desired stapling position has been selected, the actuation mechanism <NUM> can be configured in a stapling or firing mode by rotating the actuation shaft <NUM> to the first orientation. With the jaw assembly a closed configuration at a desired stapling position (as illustrated in <FIG>), a user can reposition the selector <NUM> by sliding the slider to the first position, corresponding to the first orientation of the actuation shaft <NUM> (as illustrated in <FIG>). In the first orientation of the actuation shaft <NUM>, the forward driver <NUM> is engageable with the advancing surface <NUM>, the reversing driver <NUM> is angularly misaligned with the reversing surface <NUM>, and the opening driver <NUM> angularly misaligned with the opening surface <NUM>. With the actuation shaft <NUM> in the first orientation, the movable handle <NUM> can be released into the open position (<FIG>), engaging the forward driver <NUM> with the advancing surface <NUM>.

With reference to <FIG>, with the actuation shaft <NUM> in the first orientation, and the forward driver <NUM> engaging the advancing surface <NUM>, the actuation mechanism <NUM> is in a stapling or firing mode. Several cycles of movable handle <NUM> movement from the open position to the closed position and back to the open position advance the actuation shaft <NUM> from the second position (<FIG>), to a third position in which the actuation shaft <NUM> is moved to its distal-most limit with respect to the handle assembly <NUM> (<FIG>). In some embodiments, the actuation mechanism can include a stop to interfere with distal travel of the actuation shaft <NUM> at the third position. The second position of the actuation shaft corresponds to the second position of the actuation beam in the jaw assembly <NUM>. The third position of the actuation shaft corresponds to the third position of the actuation beam in the jaw assembly <NUM> in which the plurality of staples have been deployed from the first jaw. With movement of the movable handle <NUM> or trigger in the firing mode to advance the actuation shaft from the second position to the third position, the forward driver <NUM> is sequentially advanced over the adjacent teeth or grooves of the actuating surface <NUM> in a ratchet-like advancement.

With reference to <FIG>, once the actuation shaft <NUM> has been advanced to the third position and the staples have been fired from the jaw assembly, the actuation mechanism <NUM> can be configured in a reverse mode. Accordingly, the rotation mechanism <NUM> can rotate the actuation shaft <NUM> to the second orientation to position the reversing surface <NUM> in angular alignment with the reverse driver <NUM>. The slider can be slid to the second position to rotate the actuation shaft from the first orientation (<FIG>) to the second orientation (<FIG>). With the actuation shaft <NUM> in the second orientation, repeated cycles of the movable handle <NUM> from the open position to the closed position and back to the open position engage the reverse driver <NUM> with the reversing surface <NUM> in a ratchet-like advancement while retracting the actuation shaft <NUM> proximally in the handle assembly <NUM>. Once the reverse driver <NUM> has driven the actuation shaft <NUM> proximally to the second position (illustrated in <FIG>), the opening driver <NUM> engages the opening surface <NUM>. The opening driver <NUM> returns the actuation shaft <NUM> to the first position when the movable handle <NUM> is released to the open position. (Returning the handle assembly to the configuration illustrated in <FIG>). With the actuation shaft <NUM> in the first position, the cartridge, emptied of staples, can be decoupled from the handle assembly <NUM> and a new cartridge can be coupled to the handle assembly to begin another stapling operation.

With reference to <FIG>, another embodiment of handle assembly <NUM>' for use with a surgical stapler <NUM>' is illustrated. <FIG> illustrates a side view of the handle assembly <NUM>', and <FIG> illustrates a perspective view of the handle assembly <NUM>'. In the handle assembly <NUM>', actuation of the rotation mechanism <NUM>' is accomplished with a slideable switch <NUM> that is longitudinally slideable with respect to the handle assembly <NUM>' housing. Advantageously, such a slideable switch arrangement can allow a user to easily rotate the actuation shaft <NUM> in a single-handed operation.

With reference to <FIG>, a cross-sectional view of the handle assembly <NUM>' is illustrated revealing the actuation mechanism <NUM>' and the rotation mechanism <NUM>'. The actuation mechanism functions substantially as described above with respect to the embodiment of <FIG>,<FIG>,<FIG> to advance the actuation shaft <NUM>' from a first position to a second position in an open/close mode, from the second position to a third position in a stapling mode, and from the third position to the first position in a reverse mode. The actuation mechanism <NUM>' includes corresponding forward, reverse, and opening drivers <NUM>, <NUM>, <NUM> operably coupled to a movable handle <NUM> and advancing <NUM>, reversing, and opening surfaces on the actuation shaft <NUM>' substantially as described with respect to the embodiment of <FIG>,<FIG>. However, in the embodiment illustrated in <FIG>, the actuation shaft <NUM>' is rotatable by the rotation mechanism <NUM>' discretely between a first orientation corresponding to the open/close mode of the handle assembly wherein the opening driver <NUM> engages the opening surface <NUM>, a second orientation corresponding to the stapling position, wherein the forward driver <NUM> engages the advancing surface <NUM>, and a third orientation corresponding to the reverse position wherein the reverse driver <NUM> engages the reversing surface.

With reference to <FIG>, certain aspects of the rotation mechanism <NUM>' are illustrated. The rotation mechanism <NUM>' comprises the slideable switch <NUM> longitudinally slideable with respect to the housing of the handle assembly <NUM>', a hub collar <NUM> longitudinally slideable by the switch <NUM>, and a biasing member or spring <NUM>. In the illustrated embodiment, the slideable switch <NUM> is connected to the hub collar <NUM> with a thin beam, such as a shim member. The hub collar <NUM> is rotationally fixed and longitudinally slideable with respect to the housing of the handle assembly <NUM>'. In some embodiments, the hub collar <NUM> can comprise first and second wings that can slide in corresponding first and second slots in the housing of the handle assembly to allow relative longitudinal movement and restrict relative rotational movement therebetween.

The hub collar <NUM> can be a generally tubular member disposed around the actuation shaft <NUM>'. The hub collar <NUM> can extend between a first edge <NUM> having a plurality of ramps <NUM> formed therein and a second edge <NUM> having a plurality of recesses <NUM> formed therein. In the illustrated embodiment, the hub collar <NUM> comprises three ramps <NUM> formed in the first edge <NUM> with each ramp spaced approximately <NUM> degrees apart from adjacent ramps <NUM>. As illustrated, the hub collar <NUM> comprises three recesses <NUM> formed in the second edge <NUM> with each recess <NUM> being approximately <NUM> degrees apart from adjacent recesses <NUM>. In other embodiments, the number and relative spacing of ramps <NUM> and recesses <NUM> can vary to rotate the actuation shaft <NUM> between different orientations from those of the illustrated embodiment.

In some embodiments, the rotation mechanism <NUM>' can include a spring <NUM> to bias the slideable switch <NUM> and the hub collar <NUM> to a proximal position with respect to the housing of the handle assembly <NUM>'.

With continued reference to <FIG>, the actuation shaft <NUM>' can have a first plurality of projections <NUM> projecting radially outwardly therefrom adjacent the first edge <NUM> of the hub collar <NUM>. In the illustrated embodiment, the actuation shaft has three projections <NUM> each spaced approximately <NUM> degrees from the adjacent projections. The actuation shaft <NUM>' can further comprise a second plurality of projections <NUM> extending radially outwardly from the actuation shaft <NUM>' at a position adjacent the second edge <NUM> of the hub collar <NUM>. In the illustrated embodiment, the actuation shaft <NUM>' has three projections <NUM> each spaced approximately <NUM> degrees from the adjacent projections. In other embodiments, the numbers and spacing of the projections <NUM>, <NUM> can be varied to achieve a rotation mechanism with different rotational characteristics. In some embodiments, the projections <NUM>, <NUM> can be formed on the actuation shaft <NUM>', while in other embodiments, the projections <NUM>, <NUM> can be formed separately such as on a sleeve that is adhered to, has a keyed engagement with, or is otherwise rotationally fixed to the actuation shaft <NUM>'.

With reference to <FIG>, an operation sequence of the rotation mechanism <NUM>' to rotate the actuation shaft <NUM>' from a first orientation to a second orientation is illustrated. <FIG> illustrates a schematic view of the hub collar <NUM> and actuation shaft <NUM>' in a first orientation. In the first orientation, a first projection 94a of the second plurality of projections <NUM> rests in a first recess 90a of the plurality of recesses <NUM>, and a first projection 92a of the first plurality of projections is positioned adjacent a first ramp 86a of the plurality of ramps <NUM>.

With reference to <FIG>, an operation sequence of the rotation mechanism <NUM>' as the slideable switch <NUM> is advanced distally is illustrated. As the slideable switch <NUM> is advanced distally with respect to the housing of the handle assembly, the hub collar <NUM> translates distally, bringing the first plurality of projections <NUM> into sliding engagement with the plurality of ramps <NUM> of the hub collar <NUM> (illustrated in <FIG>). Further distal advancement of the slideable switch <NUM> and hub collar <NUM> relative to the housing of the handle assembly advances the first plurality of projections <NUM> over the plurality of ramps <NUM> (illustrated in <FIG>). An angular profile of the ramps <NUM> acts as a camming surface such that travel of the first plurality of projections <NUM> along the plurality of ramps <NUM> rotates the actuation shaft <NUM>'. Once the slideable switch reaches the distal most end of its travel, the spring <NUM> biases the hub collar <NUM> and sliding switch <NUM> proximally with respect to the housing of the handle assembly <NUM>. As the hub collar <NUM> returns to a proximal position, the second plurality of projections <NUM> engages the plurality of recesses <NUM> (illustrated in <FIG>). As illustrated in <FIG>, following an actuation cycle of the slideable switch <NUM>, the first projection 94a of the second plurality of projections <NUM> has been positioned in the second recess 90b of the plurality of recesses such that the actuation shaft <NUM>' has been positioned in a second orientation rotated <NUM> degrees from the first orientation. Subsequent actuation cycles of the slideable switch <NUM> rotate the actuation shaft in discrete <NUM> degree increments.

In other embodiments, the rotation mechanism can comprise a handle directly connected to the actuation shaft. For example, a proximal end of the actuation shaft can be connected to a handle <NUM>" (<FIG>) extending proximally from the housing. Rotation of the handle relative to the longitudinal axis rotates the actuation shaft to configure the handle assembly in one of an open/close mode, a forward mode, or a reverse mode.

Claim 1:
A handle assembly (<NUM>) for a surgical stapler (<NUM>), the handle assembly (<NUM>) comprising:
a stationary handle (<NUM>);
a movable handle (<NUM>) pivotably coupled to the stationary handle (<NUM>) and pivotable between an open position spaced apart from the stationary handle (<NUM>) and a closed position adjacent the stationary handle (<NUM>);
an actuation mechanism (<NUM>) comprising:
an actuation shaft (<NUM>) defining a longitudinal axis, the actuation shaft (<NUM>) comprising an advancing surface (<NUM>) formed thereon and a reversing surface (<NUM>) formed thereon;
an advancing driver (<NUM>) operably coupled to the movable handle (<NUM>) and translatable in a first longitudinal direction with respect to the longitudinal axis responsive to movement of the movable handle (<NUM>) from the open position to the closed position;
a reversing driver (<NUM>) operably coupled to the advancing driver (<NUM>) and translatable in a second direction with respect to the longitudinal axis responsive to movement of the movable handle from the open position to the closed position, the second direction opposite the first direction; and
a gear (<NUM>) operably coupling the advancing driver (<NUM>) to the reversing driver (<NUM>); and
wherein the actuation shaft (<NUM>) is longitudinally translatable along the longitudinal axis relative to the stationary handle (<NUM>); and
characterized in that the actuation shaft (<NUM>) is selectably rotatable about the longitudinal axis between a first orientation in which the advancing driver (<NUM>) engages the advancing shaft (<NUM>) of the actuation shaft (<NUM>) to advance the actuation shaft (<NUM>) longitudinally distally and a second orientation in which the reversing driver (<NUM>) engages the reversing surface (<NUM>) of the actuation shaft (<NUM>) to retract the actuation shaft (<NUM>) longitudinally proximally.