Surgical staple cartridges

[0001] 1. Technical Field

[0002] The present invention relates to surgical cutting and stapling instruments and, in various embodiments, to disposable surgical staple cartridges.

[0003] 2. Background

[0004] Endoscopic surgical instruments are often preferred over traditional open surgical devices since a smaller incision tends to reduce the post-operative recovery time and complications. Generally, these endoscopic surgical instruments include an “end effector”, a handle assembly and an elongated shaft that extends between the end effector and the handle assembly. The end effector is the portion of the instrument configured to engage the tissue in various ways to achieve a desired diagnostic or therapeutic effect (e.g., endocutter, grasper, cutter, staplers, clip applier, access device, drug/gene therapy delivery device, and energy device using ultrasound, RF, laser, etc.).

[0005] Two primary design approaches have been used in the past by various medical component manufacturers to reduce the overall cost of endoscopic surgical instruments such as endocutters. While both attempts have been successful at addressing at least some of the user's needs, neither attempt has fully addressed all of those needs.

[0006] For example, the first design approach concerned the use of a disposable endocutter devices for each firing. Such endocutter end effectors were fabricated from relatively weak components that can only be fired once before a new end effector is required since the end effector components are markedly deformed after each firing. This type of end effector employed an “I-beam” feature on the knife to prevent the anvil from deflecting away from the cartridge during firing. Since the I-beam is riding on a relatively weak anvil component, the I-beam deforms the portion of the anvil located directly underneath the I-beam feature. This combination of factors allows staple form to be improved while decreasing the forces required to actuate the device because the I-beam is only pulling the anvil material down to the correct position relative to the cartridge where it's needed to form a staple at any given time.

[0007] While this approach improves staple form and lowers the force required to cut the tissue and deploy the staples, it has a number of disadvantages. First, having the surgeon dispose of an entire anvil, channel and cartridge after each firing adds a great deal of manufacturing expense. Second, the device often doesn't securely clamp the targeted tissue due to a combination of the relatively weak end effector components and the manner in which the anvil is actually clamped onto the tissue. The third issue is that the relatively weak end effector components can only reliably be used to fire on moderate tissue thicknesses and the components will not function on very thick tissues.

[0008] The second primary design approach taken in the past is to make much stronger end effector components that can be used for multiple firings. In this approach, only the cartridge assembly is replaced after each firing. Because the end effector components have to resist multiple firing loads, they are purposefully designed such that they do not deform after each firing. This design concept employs a different set of features on the knife to keep the anvil positioned relative to the cartridge during deployment of the staples to improve staple form. The combination of the stiffer end effector components and a different clamping mechanism allows this type of device to reliably exert high clamping loads so the surgeon can easily manipulate the desired tissue. The stiffer components also allow the end effector to be reliably used on relatively thick tissue samples.

[0009] One disadvantage of this approach, however, is that the features on the knife that prevent the anvil from deflecting away from the cartridge are now required to pull a very stiff anvil component down towards the cartridge. The knife is therefore attempting to pull an entire beam down towards the cartridge that is as long as the entire staple line instead of just pulling the anvil down in a localized region as on the previous device. This approach, therefore, generally must generate higher deployment forces due to the increased anvil drag loads on the knife.

[0010] U.S. Patent Publication No. US 2007/0175950 A1, entitled “Disposable Staple Cartridge Having an Anvil With Tissue Locator For Use With Surgical Cutting and Fastening Instrument and Modular End Effector System Therefor”, the disclosure of which is herein incorporated by reference in its entirety, discloses various disposable cartridge arrangements that employ a disposable anvil component. Such arrangement effectively address a variety of the shortcomings discussed above, but also include the additional expense of an anvil component. In addition, all of the foregoing arrangements require a separate support channel for supporting the staple cartridge therein. Such support components add to the expense of the surgical instrument.

[0011] Consequently, there is a need for a surgical staple cartridges that effectively address many of the shortcomings described above.

[0012] The foregoing discussion is intended only to illustrate some of the shortcomings present in the field of the invention at the time, and should not be taken as a disavowal of claim scope.

[0013] In accordance with general aspects of at least one form, there is provided an integrated surgical fastener cartridge assembly that comprises an elongated channel that is configured for removable attachment to a distal frame portion of a surgical instrument. In at least one form, the elongated channel has an attachment portion that comprises a wedge-shaped portion that is configured for wedging engagement with the distal frame portion. The attachment portion further comprises a locking member for releasably retaining the wedge-shaped portion in wedging engagement with the distal frame portion. The integrated surgical fastener cartridge further comprises a cartridge body that is supported in the elongated channel and operably supports a plurality of tissue fasteners therein.

[0014] In accordance with other general aspects of at least one form, there is provided a surgical staple cartridge for use with surgical stapling instruments that have a distal frame portion and an anvil movably supported thereon. In at least one form, the surgical staple cartridge comprises an elongated channel that has a proximal end portion for releasable attachment to the distal frame portion. The proximal end portion of the elongated channel has at least one angled portion that is shaped for wedging engagement with a corresponding complimentary shaped surface on the distal frame portion. A selectively movable locking member is configured for releasable engagement with one of the distal frame portion and the elongated channel such that when the locking member is in an engaged position, the at least one angled portion of the elongated channel is urged proximally into wedging engagement with the corresponding complementary shaped surface on the distal frame portion to releasably affix the elongated channel to the distal frame portion. A staple cartridge is operably supported within the elongated channel and operably supports a plurality of staples therein.

[0015] In accordance with still other general aspects of at least one form, there is provided a surgical instrument that comprises a distal frame portion and an integrated surgical staple cartridge assembly. In at least one form, the integrated surgical staple cartridge assembly comprises an elongated channel that has a proximal end portion for releasable attachment to the distal frame portion. The proximal end portion of the elongated channel has at least one angled portion that is shaped for wedging engagement with a corresponding complimentary shaped surface on the distal frame portion. A staple cartridge is operably supported within the elongated channel and operably supports a plurality of surgical staples therein. The surgical instrument further comprises a selectively movable locking member that is configured for releasable engagement with one of the distal frame portion and the elongated channel such that when the locking member is in an engaged position, the at least one angled portion of the elongated channel is urged proximally into wedging engagement with the corresponding complementary shaped surface on the distal frame portion to releasably affix the elongated channel to the distal frame portion.

[0033] Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the instruments and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the various embodiments of the present invention is defined solely by the claims. Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment”, or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment”, or “in an embodiment”, or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the 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 or more other embodiments without limitation. Such modifications and variations are intended to be included within the scope of the various invention embodiments disclosed herein and their respective equivalents.

[0034] The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” referring to the portion closest to the clinician and the term “distal” referring to the portion located away from the clinician. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical”, “horizontal”, “up”, “down”, “right” and “left” may be used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and/or absolute.

[0035] Various exemplary instruments and methods are provided for performing laparoscopic and minimally invasive surgical procedures. However, the person of ordinary skill in the art will readily appreciate that the various methods and instruments disclosed herein can be used in numerous surgical procedures and applications including, for example, in connection with “open” surgical procedures. As the present Detailed Description proceeds, those of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, etc. The working portions or end effector portions of the instruments can be inserted directly into a patient's body or can be inserted through an access device such as a trocar that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced.

[0036] Turning to the Drawings wherein like numerals denote like components throughout the several views, FIG. 1 depicts one embodiment of a surgical stapling and severing instrument 10 that is capable of practicing various unique benefits of at least one form of the present invention. Various portions of the instrument 10 may be identical to portions of the devices disclosed in U.S. Pat. No. 7,670,334, which has been herein incorporated by reference and/or U.S. Pat. No. 7,000,818, entitled “Surgical Stapling Instrument Having Separate Distinct Closing and Firing Systems”, the disclosure of which is herein incorporated by reference in its entirety.

[0037] As shown in FIG. 1, in one non-limiting form, the surgical instrument 10 generally includes a handle portion 20 that is connected to an implement portion 12, the latter further comprising a shaft assembly 14 distally terminating in an end effector 100. In at least one non-limiting embodiment, the end effector 100, in general, comprises a pair of “jaws” 102, 104 that are configured to clamp and staple tissue. As will be discussed in further detail below, one “jaw” comprises an integrated cartridge and channel assembly 120 and the other jaw comprises a movable anvil 200. The handle portion 20 includes a pistol grip 24 toward which a closure trigger 26 is pivotally drawn by the clinician to cause clamping, or closing, of the anvil 200 toward the integrated cartridge and channel assembly 120. A firing trigger 28 is farther outboard of the closure trigger 26 and is pivotally drawn by the clinician to cause the stapling and severing of clamped tissue in the end effector 100.

[0038] As is known, the closure trigger 26 is actuated first. Once the clinician is satisfied with the positioning of the end effector 100, the clinician may draw back the closure trigger 26 to its fully closed, locked position proximate to the pistol grip 24. Then, the firing trigger 28 is actuated. The firing trigger 28 springedly returns when the clinician removes pressure. A release button 30 when depressed on the proximal end of the handle portion 20 releases any locked closure trigger 26.

[0039] As will be discussed in further detail below, the integrated cartridge and channel assembly 120 is detachably coupled to a frame 50 that protrudes from the handle portion 20. The frame 50 is enclosed within a movable closure tube assembly 40 that is configured to operably interface with the closure trigger 26 on one end and the anvil 200 on the other end. When the closure tube 32 is moved proximally on the frame 50 by the closure trigger 26, the anvil 200 opens, pivoting away from the integrated cartridge and channel assembly 120. As the present Detailed Description proceeds, those of ordinary skill in the art will recognize that the various embodiments of the integrated cartridge and channel assembly 120 of the present invention may be employed with a variety of known surgical instruments designed to sever and staple tissue. Thus, the protection afforded to the various embodiments of the present invention disclosed herein and their respective equivalents should not be limited to the specific surgical instrument arrangement disclosed herein. For example, various embodiments of the present invention may be successfully employed with surgical instruments with articulatable end effectors or non-articulatable end effectors, instruments that have powered closure and firing features, instruments that have manually operated closure and firing features, instruments that are attached to robots or other automated control equipment, etc.

[0040] Turning to FIG. 2, there is shown one form of an integrated cartridge and channel assembly 120 of the present invention for attachment to the distal end portion 51 of the frame 50. In various embodiments, the integrated cartridge and channel assembly 120 comprises a molded cartridge body 122 that is formed from that is supported in an elongated channel 123. The cartridge body 122 may be configured to snappingly engage the channel 123 or it may be attached thereto by other means. The staple cartridge body 122 operably supports a plurality of staples 124 that are operably supported on corresponding staple drivers 126 that are supported within respective upwardly open staple apertures 128 formed in the cartridge body 122.

[0041] The instrument 10 further includes a firing bar 80 that is configured to longitudinally translate through the shaft assembly 14 and through a firing slot 54 in the frame 50. The firing bar 80 has a distal end portion 82 that has a sharpened cutting edge 84 formed thereon for severing tissue. A variety of firing bar configurations are known and may be adapted for use in connection with the integrated cartridge and channel assembly 120 without departing from the spirit and scope of the present invention.

[0042] In operation, the distal end portion 82 of the firing bar 80 actuates the integrated cartridge and channel assembly 120 as the firing bar 80 is driven distally therethrough. A wedge sled 90 is driven distally by the distal end portion 82 of the firing bar 80. The wedge sled 90 upwardly cams the staple drivers 126 to force out the staples 124 into deforming contact with the closed anvil 200 while the cutting edge 84 of the distal end 82 portion of the firing bar 80 severs clamped tissue. The firing bar 80 is movably supported within the shaft assembly 14 such that it passes through the integrated cartridge and channel assembly 120 when the instrument 10 is fired (e.g., actuated).

[0043] As can be seen in FIG. 2, the anvil 200 is movably supported on the distal end portion 51 of the frame 50. A pair of apertures 55 may be provided in the distal end portion 51 to movably receive trunnions or pins 202 on the anvil 200, allowing the anvil 200 to pivot from an open position to a closed position relative to the integrated cartridge and channel assembly 120 in response to opening and closing motions received from the closure tube assembly 40. in various non-limiting embodiments, the distal end 41 of the closure tube assembly 40 includes a horseshoe aperture 42 and tab 43 for engaging an opening tab 204 on the anvil 200. As is known, when the end effector closure tube assembly 40 is advanced distally on the end effector frame 50, the horseshoe aperture 42 applies a closing motion to the tab 204 to move the anvil 200 toward the integrated cartridge and channel assembly 120. When the end effector closure tube assembly 40 is withdrawn in the proximal direction, the tab 43 engages the tab 204 to move the anvil 200 away from the integrated cartridge and channel assembly 120 to an open position. In various non-limiting embodiments, a spring clip 205 is mounted in the distal end portion 51 of the end effector frame 50 as a lockout for firing bar 80 in a known manner. It will be appreciated that various embodiments may include other types of lockouts or no lockouts at all.

[0044] In various non-limiting embodiments, the elongated channel 123 has an attachment portion 130 that has at least one wedge-shaped attachment portion 132 thereon. In the embodiments depicted in FIGS. 2-8, two wedge-shaped attachment portions 132 are employed. The wedge-shaped attachment portions 132 are configured to wedgingly engage complementary-shaped angled engagement surfaces 56 formed on the distal end 51 of the frame 50 when the attachment portion 130 is moved proximally into engagement with the distal end 51 of the frame 50.

[0045] As can be seen in FIGS. 4-8, the elongated channel 123 further includes a locking member 140 for releasably retaining the wedge-shaped attachment portions 132 in wedging engagement with the angled engagement surfaces 56 on the frame 50. In various non-limiting embodiments, the locking member 140 comprises at least one locking tab 144 that is formed on a spring arm 146 that protrudes proximally from the elongated channel 123. In various non-limiting embodiments, the locking tab 144 is configured to extend into locking engagement with a locking aperture 57 in the distal end 51 of the frame 50 as shown in FIG. 7. The locking tab 144 has a locking surface 148 for engaging the edge of the locking aperture 57. In various non-limiting embodiments, the locking surface 148 may be provided with a slight angle such that when the locking surface engages the edge of the locking aperture 57, the locking surface urges the elongated channel 123 in the proximal direction “PD”. In other embodiments the locking surface 148 is substantially perpendicular to the bottom of the elongated channel 123. To enable the locking tab 114 to be biased out of the locking aperture 57, a clearance hole 46 is provided through the closure tube assembly 40 which is in registration with the locking aperture 57. To disconnect the integrated cartridge assembly 120 from the frame 50, the clinician simply applies a biasing force (force “F” in FIG. 7) to the locking tab 144 through the holes 46, 57 to bias the locking tab 144 out of engagement with the locking aperture 57. In other non-limiting embodiments, the locking tab is provided on the distal end 51 of the frame and the locking aperture is provided in the elongated channel 123. An alternative embodiment is shown in FIG. 7A wherein the spring arm 146′ protrudes from the distal end 51 of the frame 50. As can be seen in that Figure, the locking tab 144′ is configured to extend into locking engagement with a locking aperture 57′ in the proximal end of the elongated channel 123 such that the locking surface 148′ engages the locking aperture 57′.

[0046] FIGS. 8-14 illustrate another end effector 100′ embodiment in accordance with various non-limiting embodiments of the present invention. As can be seen in those Figures, the end effector 100′ includes an integrated cartridge and channel assembly 320 that has a cartridge body 322 that is supported in an elongated channel 323 that is configured for removable attachment to the distal end 51′ of the frame 50′. In various embodiments, the integrated cartridge and channel assembly 320 comprises a molded cartridge body 322 that is supported in the elongated channel. The cartridge body 322 may be configured to snappingly engage the channel 323 or it may be attached thereto by other means. The staple cartridge body 322 operably supports a plurality of staples that are supported on corresponding staple drivers that are supported within respective upwardly open staple apertures 328 formed in the cartridge body as was discussed above. It will be understood that the integrated cartridge and channel assembly 320 is substantially identical in construction and operation to the integrated cartridge and channel assembly 120 described above, except for the differences discussed below.

[0047] In various non-limiting embodiments, the elongated channel 323 has an attachment portion 430 that has at least one wedge-shaped attachment portion 432 and a proximally protruding attachment segment 450. In the embodiments depicted in FIGS. 12-14, two wedge-shaped attachment portions 432 are employed. The wedge-shaped attachment portions 432 are configured to wedgingly engage complementary-shaped angled engagement surfaces 56′ formed on the distal end 51′ of the frame 50′ when the attachment portion is moved proximally into engagement with the distal end 51′ of the frame 50′. The frame 50′ is similar in construction and operation to the integrated frame 50 described above, except for the differences discussed below. The angled engagement surfaces 56′ are formed on distally extending tangs 440 formed on the distal end 51′ of the frame 50′. Each tang 440 has a trunion hole 442 therein for receiving a corresponding anvil trunion 202. In various non-limiting embodiments, the closure tube assembly 40′ which is actuated in the same manner as closure tube assembly 40 described above, is configured to abut a closure ledge 203 formed on the anvil 200 as the closure tube assembly 40′ is driven in the distal direction “DD”. As the closure tube assembly 40′ is driven distally and abuts the closure ledge 203, the anvil 200 is pivoted to the closed position towards the integrated cartridge and channel assembly 320. In various embodiments, a spring (not shown) is attached to a proximal portion of the anvil or is otherwise employed such that as the closure tube assembly 40′ is moved in the proximal direction “PD”, the spring biases the anvil 200 into an open position (shown in FIG. 9).

[0048] As can be seen in FIGS. 9-12, the end effector 100′ further includes a locking member 460 for releasably retaining the wedge-shaped attachment portions 432 in wedging engagement with the angled engagement surfaces 56′ on the frame 50′. In various non-limiting embodiments, the locking member 460 comprises a locking ring 462 that is rotatably supported on the distal end 51′ of the frame 50′. The locking ring 462 has a pair of diametrically opposed locking tabs 464 formed on the inner surface 463 thereof. As can be seen in FIG. 12, each locking tab 464 has a proximally-facing tapered end 466 formed thereon. The locking tabs 464 are received within a radial groove 446 formed in the distal end 51′ of the frame 50′ to rotatably journal the locking ring 44 on the frame 50′.

[0049] To attach the integrated cartridge and channel assembly 320 to the frame 50′, the attachment segment 450 is inserted between the tangs 440 until the wedge shaped attachment portions 432 engage the corresponding angle attachment surfaces 56′ on the frame 50′. See FIG. 11. When in that position, the radial groove 446 in the distal end 51′ of the frame 50′, radially aligns with a retention groove 452 in the attachment segment 450. To affix the integrated cartridge and channel assembly 320 to the frame 50′, the clinician simply rotates the locking ring 462 either in the clockwise “CW” direction or counter clockwise “CCW” direction to bring one of the locking tabs 464 into locking engagement within the retention groove 452 in the attachment segment 450. As the tapered end 466 interacts with the proximal wall of the retention groove 452, the elongated channel 323 is urged proximally such that the wedge-shaped attachment portions 432 wedgingly engage the corresponding angled attachment surfaces 56′ on the frame 50′ to attach the elongated channel 323 to the frame 50′. It will be understood that when the one locking tab 462 is received in the retention groove 452, the other locking tab 462 is retained in the radial groove 446 in the distal end 51′ of the frame 50′.

[0050] Various integrated cartridge and channel assembly embodiments of the present invention may be easily attached to and detached from the surgical instrument without the need for any tools or addition instruments. 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, the device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. 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.

[0051] Preferably, the inventions described herein will be processed before surgery. First, a new or used instrument is obtained and if necessary cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in the medical facility.

[0052] Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

[0053] 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. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.