Patent Application
20100237132
The present invention generally relates to surgical staplers, and more particularly, to an anvil locking system for locking an anvil of a circular stapling instrument in place.
In certain types of surgical procedures, the use of surgical staples has become the preferred method of joining tissue and, as such, specially configured surgical staplers have been developed for these applications. For example, intra-luminal or circular staplers have been developed for use in a surgical procedure known as an anastomosis. Circular staplers useful for performing an anastomosis are disclosed, for example, in U.S. Pat. Nos. 5,104,025; 5,205,459; 5,285,945; and 5,309,927 which are each herein incorporated by reference in their respective entireties.
One form of an anastomosis comprises a surgical procedure wherein sections of intestine are joined together after a diseased portion has been excised. The procedure requires re-joining the ends of the two tubular sections together to form a continuous tubular pathway. Previously, this surgical procedure was a laborious and time consuming operation. The surgeon had to precisely cut and align the ends of the intestine and maintain the alignment while joining the ends with numerous suture stitches. The development of circular staplers has greatly simplified the anastomosis procedure and also decreased the time required to perform an anastomosis.
In general, a conventional circular stapler typically consists of an elongated shaft that has a proximal actuating mechanism and a distal stapling mechanism mounted to the shaft. The distal stapling mechanism commonly consists of a fixed stapling cartridge that contains a plurality of staples configured in a concentric circular array. A round cutting knife is concentrically mounted in the cartridge interior to the staples for axial travel therein. Extending axially from the center of the cartridge is a movable trocar shaft that is adapted to have a staple anvil removably coupled thereto. The anvil is configured to form the ends of the staples as they are driven into it. The distance between a distal face of the staple cartridge and the staple anvil is controlled by an adjustment mechanism mounted to the proximal end of the stapler shaft for controlling the axial movement of the trocar. Tissue clamped between the staple cartridge and the staple anvil is simultaneously stapled and cut when the actuating mechanism is activated by the surgeon.
When performing an anastomosis using a circular stapler, the intestine is typically stapled using a conventional surgical stapler with double rows of staples being emplaced on either side of the diseased portion of intestine to be removed. The target section is simultaneously cut as the adjoining end is stapled. After removing the diseased portion, the surgeon typically inserts the anvil into the proximal end of the lumen, proximal of the staple line. This is done by inserting the anvil head into an entry port cut into the proximal lumen by the surgeon. On occasion, the anvil can be placed transanally, by placing the anvil head on the distal end of the stapler and inserting the instrument through the rectum. The surgeon then ties the proximal end of the intestine to the anvil shaft using a suture or other conventional tying device. Next, the surgeon cuts excess tissue adjacent to the tie and the surgeon attaches the anvil to the trocar shaft of the stapler. The surgeon then closes the gap between the anvil and cartridge, thereby clamping the proximal and distal ends of the intestine in the gap. The surgeon next actuates the stapler causing several rows of staples to be driven through both ends of the intestine and formed, thereby joining the ends and forming a tubular pathway. Simultaneously, as the staples are driven and formed, the concentric circular knife blade is driven through the intestinal tissue ends, cutting the ends adjacent to the inner row of staples. The surgeon then withdraws the stapler from the intestine and the anastomosis is complete.
During the above-described surgical procedures, the clinician generally strives to obtain a tight enough staple line to prevent leakage and bleeding and to achieve “tissue-to-tissue” contact which promotes tissue healing. In general, by controlling the amount of compression that is applied to the tissue, better stapling and healing results will be achieved. Achieving a desired amount of tissue compression becomes challenging when dealing with thick tissues and thin tissues. For example, when stapling thinner tissue, it is necessary to move to the lower end of the compression range to obtain compression of the tissue—without over compressing it. When stapling thicker tissues, the proper compression will be achieved at a larger gap setting.
A simple robust means to measure this compression would be to use a compliant member and an indicator to measure displacement similar to a spring force scale. Such arrangements, however, must be able to withstand the forces required to form the staples and to cut through a break away washer which is commonly mounted in the anvil. In some instances, for example, such forces may exceed 300 lbf and must be restrained without deflection to ensure the proper formed staple height is achieved. Such devices, however, present additional challenges to the user. In particular, once the anvil has been properly positioned, it is necessary that the anvil not move during firing. Those anvil systems that are compliant in nature may facilitate undesirable movement or deflection of the anvil during firing which could adversely affect proper staple formation.
Thus, the need exists for an anvil locking system that can be used to selectively retain the anvil in a desired position during stapling.
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.
The invention overcomes the above-noted and other deficiencies of the prior art by providing a surgical stapling instrument for applying one or more surgical staples to tissue. Various embodiments comprise a handle assembly and a shaft assembly that is coupled to the handle assembly. A stapling head assembly may be operably coupled to the shaft assembly. The stapling head assembly may comprise a staple cartridge for supporting one or more surgical staples, a staple driver for engaging and driving the staples from the staple cartridge, and a knife that is movably supported in the stapling head assembly. The surgical stapling instrument may further include a drive system for applying drive motions to the staple driver and the knife. An anvil is movably supported relative to the staple cartridge for axial movement toward and away from the staple cartridge. The instrument may also include an anvil adjustment assembly for selectively adjusting an axial position of the anvil relative to the staple cartridge. The instrument also comprises an anvil locking system configured to cooperate with the anvil adjustment assembly to selectively lock and unlock the anvil in axial position relative to the staple cartridge.
In another general aspect of the present invention, there is provided a surgical stapling instrument for applying one or more surgical staples to tissue. Various embodiments may comprise a handle assembly and a stapling head assembly that is operably coupled to the handle assembly. An anvil is movably supported relative to the stapling head assembly for selective axial travel toward and away from the stapling head assembly. An anvil adjustment assembly is supported by the handle assembly for selectively adjusting an axial position of the anvil relative to the staple cartridge. An anvil locking system is configured to cooperate with the anvil adjustment assembly to selectively lock and unlock the anvil in axial positions relative to the stapling head.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.
Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices 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. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.
Turning to the Drawings, wherein like numerals denote like components, there is shown a circular stapler 10 that includes a unique and novel system for locking the anvil in position while the stapler is being actuated to cut tissue and simultaneously form staples in the adjacent tissue. One form of circular stapler that may employ the anvil locking system embodiments of the present invention is disclosed in U.S. Patent Publication No. US 2008/0078806A1, the disclosure of which is herein incorporated by reference in its entirety. However, as the present Detailed Description proceeds, those of ordinary skill in the art will readily appreciate that the various anvil locking system embodiments of the present invention may be successfully employed with various other circular stapler configurations without departing from the spirit and scope of the present invention.
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” and “down” 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.
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The anvil adjustment assembly, generally designated as 59, includes the trocar 60 and related structure employed to axially move the trocar 60 (and the anvil 100 when attached thereto) relative to the stapling head assembly 12. The trocar 60 may include a trocar tip 62 that has attached thereto a top tension band 65 and a bottom tension band 67. The trocar tip 62 may be coupled to the top tension band 65 and bottom tension band 67 by fasteners 61 (e.g., screws, studs, posts, etc.). A spacer band 63 may be received within the tubular shroud 51 and serves to slidably support the upper and lower tension bands 65, 67 within the shroud 51. The proximal ends of the top tension band 65 and bottom tension band 67 may be attached to a distal end of an adjustment shaft 80. As illustrated in
In various embodiments, the adjusting shaft 80 is axially movably supported within a handle assembly 40 that may comprise two handle casing segments 41 that are interconnected together by suitable fastener arrangements for ease of assembly. The trigger 14 is pivotally attached to the handle assembly 40 by a pivot pin 300. A spring 302 is supported on pivot pin 300 and serves to bias the trigger 14 away from the handle assembly 40 to an unactuated position. As can be seen in
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Various embodiments of the present invention include a unique and novel anvil locking system generally designated as 400 for, among other things, locking the anvil 100 in an axial position relative to the staple head assembly 12 during firing. One embodiment of the anvil locking system 400 includes a first locking member 402 that is coupled to the distal end portion 81 of the adjustment shaft 80. In various embodiments, the first locking member comprises an elongated gear rack 402. The gear rack 402 may be integrally formed with or otherwise attached to the distal end portion 81 of the adjustment shaft 80. Thus, the gear rack 402 will move axially with the adjustment shaft 80 in the proximal direction “PD” and the distal direction “DD”.
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The locking assembly 400 further includes a second locking gear 430 that is rotatably pinned to a locking yoke 440 by a pin 450. The locking yoke 440 has a distal end 442 that may also be rotatably mounted on pin 30 such that the locking yoke 440 may pivot about the second axis B-B. The pin 450 defines a third axis C-C that is also substantially transverse to the longitudinal axis A-A and substantially parallel to the second axis B-B. See
Once the anvil 100 has been coupled to the trocar 60, the axial position of the anvil 100 relative to the staple cartridge 24 may be adjusted by rotating the closure knob 350 relative to the handle assembly 40. For example, by rotating the closure knob 350 in one direction, the anvil 100 is axially advanced in the distal direction “DD” away from the staple cartridge 24 to increase the gap “G” therebetween. By rotating the closure knob 350 in a second direction (opposite to the first direction), the anvil 100 is axially drawn towards the staple cartridge 24 in the proximal direction “PD” to thereby decrease the gap “G”. See
As shown in
Those of ordinary skill in the art will appreciate that such arrangement serves to lock the anvil 100 in place prior and during firing of the staples. Because the first locking gear 420 is always in engagement with the gear rack 402 and the second locking gear 430 is engaged with the first locking gear 420, a locking engagement with the gear rack 402 can be achieved with high positional accuracy. A slight clearance may be provided between the locking yoke 440 and the pin 300 to allow for slight rack engagement errors without compromising positional accuracy. It will be further appreciated that the tooth profile on the gear rack 402 can also be advantageously designed to facilitate the arcuate motion of the second locking gear 430 during engagement.
In various embodiments, the locking yoke 440 may be provided in the configuration depicted in
In various embodiments, the locking system 400″ may be provided with the following gear ratios, for example:
When performing an anastomosis using a circular stapler, the intestine may be stapled using a conventional surgical stapler with multiple rows of staples being emplaced on either side of a target section (i.e., specimen) of intestine. The target section is typically simultaneously cut as the section is stapled. After removing the target specimen, the surgeon inserts the anvil into the proximal portion of the intestine, proximal of the staple line. This is typically done by inserting the anvil head into an entry port cut into the proximal intestine portion and forcing the anvil shaft through the proximal staple line. The instrument minus the anvil is passed transanally to the distal staple line and the anvil trocar is forced through the staple line. Next, the surgeon attaches the anvil to the trocar tip of the stapler. Once the anvil has been properly coupled to the trocar tip, the anvil is inserted into the distal portion of the intestine. The surgeon then begins to rotate the closure knob assembly 350 to draw the anvil 100 toward the cartridge 24 supported in the stapling head 12 to close the gap between the anvil 100 and cartridge 24 and thereby engage the proximal end of the distal intestine portion with the distal end of the proximal intestine portion in the gap. The surgeon continues to rotate the closure knob 350 until the desired gap G and tissue compression is attained. Thereafter, the surgeon may engage the anvil locking systems 400, 400′, whichever the case may be and then fire the stapler 10 by depressing the firing trigger 14. Depressing the trigger 14 causes the compression shaft 56 to drive the staple driver 22 distally to drive the staples 90 to be driven through both ends of the intestine. Simultaneously, as the staples are driven and formed, the knife 70 is driven through the intestinal tissue ends, cutting the ends adjacent to the inner row of staples 90.
The various embodiments of the present invention represent a vast improvement over prior circular staple arrangements that fail to provide any means for locking the anvil in a firing position. While several embodiments of the invention have been described, it should be apparent, however, that various modifications, alterations and adaptations to those embodiments may occur to persons skilled in the art with the attainment of some or all of the advantages of the invention. For example, 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. This application is therefore intended to cover all such modifications, alterations and adaptations without departing from the scope and spirit of the disclosed invention as defined by the appended claims.
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 an 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 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 of ordinary skill in the art will appreciate that the reconditioning of a device can utilize a variety of different 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.
Preferably, the invention 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 higher 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.
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.
The invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. The embodiments are therefore to be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such equivalents, variations and changes which fall within the spirit and scope of the present invention as defined in the claims be embraced thereby.
