Cartridge body design with force reduction based on firing completion

A surgical instrument includes a sled and an end effector. The end effector includes a first jaw, a second jaw movable relative to the first jaw, an anvil, and a cartridge channel. The staple cartridge includes a proximal end, a distal end, a cartridge body, and staples supported in the cartridge body, wherein the sled is movable to deploy the staples from the cartridge body against tissue captured between the staple cartridge and the anvil. The cartridge channel is configured to removably retain the staple cartridge, wherein a load is required to remove the staple cartridge from the cartridge channel, and wherein the sled is configured to reduce the cartridge removal load.

BACKGROUND

The present invention relates to surgical instruments and, in various arrangements, to surgical stapling and cutting instruments and staple cartridges for use therewith that are designed to staple and cut tissue.

DETAILED DESCRIPTION

Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. Well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. The reader will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and illustrative. Variations and changes thereto may be made without departing from the scope of the claims.

Although various aspects of the present disclosure have been described herein in connection with linear staplers, these aspects can be similarly implemented in other surgical staplers such as, for example, circular staplers and/or curved staplers. Also although various aspects of the present disclosure are described in connection with a hand-held instrument, these aspects can be similarly implemented in robotic surgical systems. Various suitable robotic surgical systems are disclosed in U.S. Patent No. 2012/0298719, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, filed May 27, 2011, now U.S. Pat. No. 9,072,535, the entire disclosure of which is incorporated by reference herein.

Referring primarily toFIGS. 1-3, a surgical stapling instrument10comprises a shaft11and an end effector12extending from the shaft11. The end effector12comprises a first jaw14and a second jaw15. The first jaw14comprises a staple cartridge16. The staple cartridge16is insertable into and removable from a cartridge pan or channel17of the first jaw14; however, other embodiments are envisioned in which the staple cartridge16is not removable from, or at least readily replaceable from, the first jaw14. The second jaw15comprises an anvil18configured to deform staples ejected from the staple cartridge16. The second jaw15is pivotable relative to the first jaw14about a closure axis; however, other embodiments are envisioned in which the first jaw14is pivotable relative to the second jaw15. The surgical stapling instrument10further comprises an articulation joint20configured to permit the end effector12to be rotated, or articulated, relative to the shaft11. The end effector12is rotatable about an articulation axis extending through the articulation joint20. Other embodiments are envisioned which do not include an articulation joint.

Referring toFIG. 2, in various examples, the surgical stapling instrument10includes a housing34that comprises a handle assembly35that is configured to be grasped, manipulated, and actuated by the clinician. The housing34is configured for operable attachment to an interchangeable shaft assembly36, which includes the end effector12and at least a portion of the shaft11. In accordance with the present disclosure, various forms of interchangeable shaft assemblies may be effectively employed in connection with robotically controlled surgical systems as well hand-held instruments. The term “housing” may encompass a housing or similar portion of a robotic system that houses or otherwise operably supports at least one drive system configured to generate and apply at least one control motion that could be used to actuate interchangeable shaft assemblies. The term “frame” may refer to a portion of a hand-held surgical instrument. The term “frame” also may represent a portion of a robotically controlled surgical instrument and/or a portion of the robotic system that may be used to operably control a surgical instrument. Interchangeable shaft assemblies may be employed with various robotic systems, instruments, components, and methods disclosed in U.S. Pat. No. 9,072,535, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, which is herein incorporated by reference in its entirety.

Referring primarily toFIGS. 3 and 4, the staple cartridge16comprises a cartridge body21. The cartridge body21includes a proximal end22, a distal end23, and a deck24extending between the proximal end22and the distal end23. In use, the staple cartridge16is positioned on a first side of the tissue to be stapled and the anvil18is positioned on a second side of the tissue. The anvil18is moved toward the staple cartridge16to compress and clamp the tissue against the deck24. Thereafter, staples25(FIG. 7) removably stored in the cartridge body21can be deployed into the tissue. The cartridge body21includes staple cavities26defined therein wherein the staples25are removably stored in the staple cavities26. The staple cavities26are generally arranged in six longitudinal rows. Three rows of the staple cavities26are positioned on a first side of a longitudinal slot27and three rows of the staple cavities26are positioned on a second side of the longitudinal slot27. Other arrangements of the staple cavities26and the staples25may be possible.

The staples25are supported by staple drivers28in the cartridge body21. The staple drivers28are movable between a first, or unfired position, and a second, or fired, position to eject the staples25from the staple cavities26. The staple drivers28are retained in the cartridge body21by a pan or retainer30which extends around the bottom of the cartridge body21and includes resilient members31configured to grip the cartridge body21and hold the retainer30to the cartridge body21. The staple drivers28are movable between their unfired positions and their fired positions by a sled32. The sled32is movable between a proximal position40(FIG. 6) adjacent the proximal end22and a distal position41(FIG. 7) adjacent the distal end23. The sled32comprises a plurality of ramped surfaces33configured to slide under the staple drivers28and lift the staple drivers28, and the staples25supported thereon, toward the anvil18.

Further to the above, the sled32is moved distally by a firing member (not shown). The firing member is configured to contact the sled32and push the sled32from the proximal position40(FIG. 6) adjacent the proximal end22toward the distal position41(FIG. 7) adjacent the distal end23. The longitudinal slot27defined in the cartridge body21is configured to receive the firing member. The anvil18also includes a slot (not shown) configured to receive the firing member. The firing member further comprises a first cam which engages the first jaw14and a second cam which engages the second jaw15. As the firing member is advanced distally, the first cam and the second cam can control the distance, or tissue gap, between the deck24of the staple cartridge16and the anvil18. The firing member also comprises a knife configured to incise the tissue captured intermediate the staple cartridge16and the anvil18.

To properly deploy the staples from the staple cartridge by a firing member, the staple cartridge must be properly retained in the cartridge channel. Accordingly, it is desirable for the staple cartridge to be tightly secured to the cartridge channel for successful firing. After the staple cartridge is fired, however, a user may struggle to remove a fired staple cartridge that is tightly secured to the cartridge channel. The present disclosure provides various mechanisms for ensuring a tight attachment between an unfired staple cartridge and the cartridge channel, wherein the tight attachment is loosened or reduced by the firing mechanism to facilitate removal of the fired staple cartridge. In various examples, the tight attachment is loosened or reduced at a final stage of the firing process. In various examples, the tight attachment is loosened or reduced during the firing of the most distal group of staples. In various examples, the attachment is loosened or reduced when the sled32is adjacent the distal end23of the staple cartridge16.

In various examples, the staple cartridge16includes one or more retaining members that are configured to ensure a tight attachment between an unfired staple cartridge16and a cartridge channel17. The retaining members can be moved, or otherwise modified, during the firing of the staple cartridge16to yield a reduced attachment between the fired staple cartridge16and the cartridge channel17. The reduced attachment permits a user to easily remove the fired staple cartridge16from the cartridge channel17.

In the example illustrated inFIGS. 4 and 5, the staple cartridge16is removably seated in the cartridge channel17. The staple cartridge16includes two retaining members37on opposite sides of the staple cartridge16. The retaining members37are configured to maintain, or to help maintain, a tight attachment between the staple cartridge16and the cartridge channel17. The retaining members37may extend from a base19of the retainer30. In various examples, the retaining members37are spaced apart from walls39of the retainer30to permit the retaining members37to flex relative to the walls39. In the example illustrated inFIG. 5, the retaining members37are separated from the walls39by slits48.

Each retaining member37is in the form of a resilient member movable between a biased configuration (FIG. 8) in an unfired staple cartridge16, and an unbiased, or less biased, configuration (FIG. 9) in a fired staple cartridge16. In the unfired staple cartridge16, the retaining member37is biased into an engagement with the cartridge channel17to maintain, or to help maintain, a pre-firing cartridge removal load. A load greater than or equal to the pre-firing cartridge removal load is needed to separate an unfired staple cartridge16from the cartridge channel17.

In the fired staple cartridge16, the engagement between the retaining member37is lessened, or eliminated, which yields a post-firing cartridge removal load that is less than the pre-firing cartridge removal load. The post-firing cartridge removal load permits a user to easily remove the fired staple cartridge16from the cartridge channel17.

Referring primarily toFIGS. 4 and 8, each retaining member37includes a first curved portion44that defines a first retention feature or detent receivable in a depression or groove45defined in a side wall46of the cartridge channel17. The first curved portion44is retained in the groove45while the retaining member37is in the biased configuration. Each retaining member37further includes a second curved portion47that defines a second retention feature detent configured to rest against at least one staple driver28while the retaining member37is in the biased configuration. The cartridge body21includes a window29that exposes the at least one staple driver28to permit the second curved portion47to rest against the at least one staple driver28. In various examples, each retaining member37defines a plane transecting the base19, wherein the first curved portion44defines a first detent on the first side of the plane, and wherein the second curved portion47defines a second detent on the second side of the plane.

Prior to firing the staple cartridge16seated in the cartridge channel17, as illustrated inFIGS. 8 and 10, the retaining member37is biased an interference distance (d1) by the at least one staple driver28toward the side wall46, which causes the first curved portion44to be secured in the groove45yielding the pre-firing cartridge removal load.

During firing, however, the sled32(FIG. 7) is advanced by the firing member causing the at least one staple driver28to be lifted or moved out of engagement, or at least partially out of engagement, with the retaining member37. As illustrated inFIGS. 9 and 11, removal of the at least one staple driver28causes the retaining member37to return to the unbiased, or less biased, configuration, which causes the first curved portion44to fall out of engagement, or at least partially out of engagement, with the groove45yielding the post-firing cartridge removal load. As illustrated inFIG. 11, the retaining member37is biased an interference distance (d2) from a natural position, the interference distance (d2) being less than the interference distance (d1).

As described above, the sled32comprises a plurality of ramped surfaces33configured to slide under the staple drivers28and lift the staple drivers28, and the staples25supported thereon, toward the anvil18. As illustrated inFIGS. 10 and 11, the lifting of the at least one staple driver28by the sled32from a first position (FIG. 10) to a second position (FIG. 11), creates a gap49that is readily occupied by the retaining member37in the unbiased, or slightly biased, configuration.

In some examples, the first curved portion44remains partially inserted in the groove45in the unbiased configuration. Consequently, the retaining member37contributes to the post-firing cartridge removal load. In other examples, however, the first curved portion44may be fully removed from the groove45in the unbiased configuration. In the other examples, the retaining member37does not contribute to the post-firing cartridge removal load, which can be governed by the friction between the walls39of the staple cartridge16and the cartridge channel17. In some examples, the first curved portion44of the retaining member37is replaced with two adjacent but separate curved portions that are received in two separate but adjacent grooves in the side wall46of the cartridge channel17. In such examples, the two curved portions of the retaining member37are secured in the two grooves of the side wall46in the biased configuration yielding the pre-firing cartridge removal load. In the unbiased configuration, however, only one of the two curved portions remains secured in its groove yielding a post-firing cartridge removal load that is less than the pre-firing cartridge removal load. The examples ofFIGS. 8-11depict the retaining member37as a resilient member that yields the pre-firing cartridge removal load in a biased configuration and the lesser post-firing cartridge removal load in an unbiased, or less biased, configuration. In other examples, however, the retaining member37need not be a resilient member. In some examples, the retaining member37can be actively moved from the first position corresponding to the pre-firing cartridge removal load and the second position corresponding to the lesser post-firing cartridge removal load. In at least one example, the retaining member37can be configured to pivot between the first position and the second position about a pin. In the first position, the first curved portion44can be secured in the groove45. The sled32, or the firing member, can be configured to cause the retaining member37to move from the first position to the second position to cause the first curved portion44to fall out of engagement with the groove45, for example.

In an alternative embodiment, as illustrated in the example ofFIGS. 12-17, a staple cartridge16′, which is similar in many respects to the staple cartridge16, can be removably seated in the cartridge channel17. The staple cartridge16′, however, includes retaining members57that do not directly rest against the staple drivers28in the biased configuration. As best illustrated inFIGS. 16 and 17, the retaining members57are configured to rest, in the biased configuration, against a flexible portion51of the cartridge body21of the staple cartridge16′. In other words, the staple drivers28of the staple cartridge16′ are not directly exposed to the retaining members57but, instead, are configured to provide support for the retaining members57through the flexible portion51. In various examples, as illustrated inFIG. 12, the flexible portion51is formed by creating slits61in a side wall62of the cartridge body21.

Like the staple cartridge16, the staple cartridge16′ includes two retaining members57on opposite sides of the staple cartridge16′. The retaining members57are configured to maintain, or to help maintain, a tight attachment between the staple cartridge16′ and the cartridge channel17. Unlike the retaining members37of the staple cartridge16, the retaining members57of the staple cartridge16′ do not extend from the base19of the retainer30. On the contrary, the retaining members57are separated from the base19by a slit58. Instead, the retaining members57extend toward the base19, and can be formed creating slits60in walls39of the retainer30to permit the retaining members to flex relative to the walls39.

Like the retaining members37, each retaining member57includes a curved portion54that defines a retention feature or detent receivable in the depression or groove45defined in the side wall46of the cartridge channel17. The curved portion54is retained in the groove45while the retaining member57is in the biased configuration to maintain, or to help maintain, a tight attachment between the staple cartridge16′ and the cartridge channel17.

Prior to firing the staple cartridge16′ seated in the cartridge channel17, as illustrated inFIG. 16, the retaining member57is biased an interference distance (d1) by the at least one staple driver28toward the side wall46, which causes the curved portion54to be secured in the groove45yielding the pre-firing cartridge removal load.

During firing, however, the sled32is advanced by the firing member causing the at least one staple driver28to be lifted or moved out of engagement, or at least partially out of engagement, with the flexible portion51. Consequently, as illustrated inFIG. 17, the flexible portion51flexes toward the space previously occupied by the at least one staple driver28, which permits the retaining member57to return to the unbiased, or less biased, configuration, which causes the curved portion54to fall out of engagement, or at least partially out of engagement, with the groove45yielding the post-firing cartridge removal load. In the less biased configuration, as illustrated inFIG. 17, the retaining member57is biased an interference distance d2from a natural position, the interference distance d2being less than the interference distance d1.

In some examples, the curved portion54remains partially inserted in the groove45in the unbiased configuration. Consequently, the retaining member57contributes to the post-firing cartridge removal load. In other examples, however, the curved portion54may be fully removed from the groove45in the unbiased configuration. In the other examples, the retaining member57does not contribute to the post-firing cartridge removal load, which can be governed by the friction between the walls39of the staple cartridge16and the cartridge channel17.

In the examples ofFIGS. 4-17, the retaining members37and57are portrayed in a biased configuration while engaged with the groove45, and in an unbiased, or less biased, configuration while disengage, or partially disengaged, from the groove45. In other examples, however, retaining members of the staple cartridge can be configured to be in a natural or unbiased configuration while engaged with the groove45. An external force can be applied, for example by the sled32, to bias such retaining members out of engagement with corresponding groove45during firing of the staple cartridge.

In various examples, the post-firing cartridge removal load is about 10% to about 90% less than pre-firing cartridge removal load. In at least one example, the post-firing cartridge removal load is about 40% to about 60% less than pre-firing cartridge removal load. In at least one example, the post-firing cartridge removal load is about 50% less than pre-firing cartridge removal load.

In various aspects, a surgical instrument, similar in many respects to the surgical instrument10, has a post-firing cartridge removal load higher than its pre-firing cartridge removal load. The higher post-firing removal load can prevent a spent, also referred to herein as fired, staple cartridge from being removed after firing, which effectively rendering the surgical instrument unusable.

Preventing a fired staple cartridge from being removed from a cartridge channel of the surgical instrument after firing can be advantageous in situations where reusing the surgical instrument after firing is undesirable. For example, the higher post-firing cartridge removal load of a surgical instrument, relative to its pre-firing cartridge removal load, can be in situation involving firing a non-sterile (e.g. endoscopic) staple cartridge. After firing the non-sterile staple cartridge with the surgical instrument, the surgical instrument becomes non-sterile as well. The higher post-firing cartridge removal load prevents the spent staple cartridge from being removed from the surgical instrument ensuring that the surgical instrument will not be reused.

In one example, the post-firing cartridge removal load can be increased to prevent removal of a spent staple cartridge by employing a locking feature that is retained in a biased configuration prior to firing a staple cartridge. During firing, the locking feature snaps into a locking engagement with the cartridge channel preventing removal of the spent staple cartridge from the cartridge channel. The cartridge channel may include a retaining window that receives the locking feature.

In one aspect, the staple drivers can be utilized to maintain the locking feature in its biased configuration. During firing of the staple cartridge, as the staple drivers are lifted by the sled, the locking feature is freed from its engagement with the staple drivers. The biasing force causes the locking feature to snap into locking engagement with the cartridge channel. More than one locking feature can be employed along the length of a staple cartridge to ensure that the spent staple cartridge remains attached to the cartridge channel.

In various examples, a higher post-firing cartridge removal load of a surgical instrument, relative to its pre-firing cartridge removal load, can be beneficial in ensuring that the surgical instrument will not be used beyond a predetermined number of firings. In at least one example, a firing assembly of the surgical instrument can be slightly advanced into the last fired staple cartridge preventing its removal from the surgical instrument. A controller of the surgical instrument can be configured to track the number of firings performed by the surgical instrument. Upon reaching a predetermined number of firings, the controller may activate a motor to slightly advance the firing assembly into the staple cartridge, which prevents removal of the last spent, or fired, staple cartridge to prevent the surgical instrument from being reused beyond its safe limits.

In another example, a higher post-firing cartridge removal load of a surgical instrument, relative to its pre-firing cartridge removal load, can be beneficial in permanently deactivating a defective surgical instrument. A controller of the surgical instrument can be configured to track various performance parameters of the surgical instrument. The controller may prevent the surgical instrument from being reused if the controller detects a defect in the surgical instrument. As described above, preventing the surgical instrument from being reused can be achieved by preventing removal of the last spent, or fired, staple cartridge. Suitable controllers, motors, and firing assemblies for use in preventing a spent, or fired, staple cartridge from being removed from the surgical instrument are disclosed in U.S. patent application Ser. No. 13/803,210, titled SENSOR ARRANGEMENTS FOR ABSOLUTE POSITIONING SYSTEM FOR SURGICAL INSTRUMENTS, and filed Mar. 14, 2013, now U.S. Patent Application Publication No. 2014/0263538, which is hereby incorporated by reference herein in its entirety.

Although various devices have been described herein in connection with certain embodiments, modifications and variations to those embodiments may be implemented. Particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined in whole or in part, with the features, structures or characteristics of one ore more other embodiments without limitation. Also, where materials are disclosed for certain components, other materials may be used. Furthermore, according to various embodiments, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to perform a given function or functions. The foregoing description and following claims are intended to cover all such modification and variations.

The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, a device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps including, but not limited to, the disassembly of the device, followed by cleaning or replacement of particular pieces of the device, and subsequent reassembly of the device. In particular, a reconditioning facility and/or surgical team can disassemble a device and, after cleaning and/or replacing particular parts of the device, the device can be reassembled for subsequent use. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles.

EXAMPLES

A surgical instrument that comprises a sled and an end effector. The end effector comprises a first jaw, a second jaw movable relative to the first jaw, an anvil, and a staple cartridge. The staple cartridge comprises a proximal end, a distal end, a cartridge body, a staple supported in the cartridge body, and a staple driver. The sled is configured to deploy the staple from the cartridge body by moving the staple driver from a first position to a second position. The end effector further comprises a cartridge channel configured to removably retain the staple cartridge. A first load is required to remove the staple cartridge from the cartridge channel while the staple driver is in the first position. A second load that is less than the first load is required to remove the staple cartridge from the cartridge channel while the staple driver is in the second position.

The surgical instrument of Example 1, wherein the sled is movable between the proximal end and the distal end to deploy the staple.

The surgical instrument of Example 2, wherein the first load is reduced to the second load during the movement of the sled toward the distal end.

The surgical instrument of Example 1, 2, or 3 wherein the cartridge body comprises a window corresponding to the first position of the staple driver.

The surgical instrument of Example 1, 2, 3, or 4, further comprising a retaining member configured to rest against the staple driver while the driver is in the first position.

The surgical instrument of Example 5, wherein the retaining member is maintained in a biased configuration by the staple driver while the driver is in the first position.

The surgical instrument of Example 5 or 6, wherein the retaining member is configured to return to a less biased configuration when the staple driver is moved to the second position.

The surgical instrument of Example 5, 6, or 7, wherein the retaining member comprises a detent, and wherein the cartridge channel comprises a groove configured to receive the detent while the staple driver is in the first position.

The surgical instrument of Example 8, wherein the detent is at least partially removed from the groove while the staple driver is in the second position.

The surgical instrument of Example 8 or 9, wherein the detent is a first detent, and wherein the retaining member comprises a second detent supportable by the staple driver while the staple driver is in the first position.

A staple cartridge removably attachable to a cartridge channel of a surgical instrument. The staple cartridge comprises a proximal end, a distal end, and a cartridge body. The cartridge body comprises a deck extending between the proximal end and the distal end, a staple deployable into tissue positioned against the deck, a staple driver movable between a first position and a second position to deploy the staple from the cartridge body, and a flexible portion positioned against the staple driver while the staple driver is in the first position. The staple cartridge further comprises a retainer attached to the cartridge body. The retainer comprises a resilient member positioned against the flexible portion. The flexible portion is configured to maintain the resilient member in a biased configuration while the staple driver is in the first position.

The staple cartridge of Example 11, wherein the movement of the staple driver from the first position to the second position causes the flexible portion to flex, which causes the resilient member to return to a less biased configuration.

The staple cartridge of Example 11 or 12, wherein the movement of the staple driver from the first position to the second position causes the flexible portion to flex, which causes the resilient member to return to a less biased configuration.

The staple cartridge of Example 13, wherein the detent is configured to maintain a post-firing load for removing the cartridge from the cartridge channel in the less biased configuration, and wherein the post-firing load is less than the pre-firing load.

The staple cartridge of Example 11, 12, 13, or 14, wherein the flexible portion is positioned between the staple driver and the resilient member while the staple driver is in the first position.

The staple cartridge of Example 11, 12, 13, 14, or 15, wherein the retainer includes a base and a side wall extending from the base, wherein the resilient member is defined in the side wall, and wherein the resilient member is spaced apart from the base.

The staple cartridge of Example 11, 12, 13, 14, 15, or 16, wherein the cartridge body further comprises a side wall, and wherein the flexible portion is defined in the side wall.

A surgical instrument that comprises a sled and an end effector. The end effector comprises a first jaw, a second jaw movable relative to the first jaw, an anvil, and a staple cartridge. The staple cartridge comprises a proximal end, a distal end, a cartridge body, and staples supported in the cartridge body. The sled is movable to deploy the staples from the cartridge body against tissue captured between the staple cartridge and the anvil. The end effector further comprises a cartridge channel configured to removably retain the staple cartridge, wherein a load is required to remove the staple cartridge from the cartridge channel, and wherein the sled is configured to reduce the cartridge removal load.

The surgical instrument of Example 18, wherein the sled is movable from a first position adjacent the proximal end to a second position adjacent the distal end to deploy the staples.

The surgical instrument of Example 18 or 19, wherein the cartridge removal load is reduced during the movement of the sled.