Abstract:
A surgical stapling and cutting device is constructed with a knife safety lockout element to prevent a knife element from cutting tissue if staples cannot be applied first to the tissue prior to being cut. The surgical stapling and cutting device comprises of a staple holder for holding a staple cartridge, an anvil movably coupled to the staple holder for opposing and deforming staples, a knife safety lockout element for blocking a knife element from being deployed, and a safety spring element for activating or biasing the knife safety lockout element into an active state to block the knife element from being deployed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority of U.S. Provisional Patent Application Ser. No. 61/635,116, Attorney Docket No. 349, filed on Apr. 18, 2012, which is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention is generally related to surgical stapling devices. 
       BACKGROUND 
       [0003]    A linear cutter is a surgical instrument that staples and cuts tissue, such as gastrointestinal tissue or other tissues of a patient. The linear cutter staples and cuts the target tissue such that the cut portions of the transected tissue are hemostatic. A typical linear cutter holds a disposable single-use staple cartridge with several rows of staples held within it, and it usually includes an anvil to oppose the staples as they are deployed from the staple cartridge. During a surgical operation, such as a minimally invasive procedure, the surgeon inserts the linear cutter through an opening in the body, orients the end of the linear cutter around the target tissue to be transected, and compresses the anvil and cartridge together to clamp that tissue. Then, a row or rows of staples are deployed on either side of the transection line, and a blade is advanced along the transection line to divide or cut the tissue. Since the divided or cut portions of the tissue were stapled, they are hemostatic after the cut. 
         [0004]    During actuation of a linear cutter, the cartridge typically fires all of the staples that it holds. In order to deploy more staples, the linear cutter must be moved away from the surgical site and removed from the patient, after which the old cartridge is exchanged for a new cartridge. The linear cutter is then reinserted into the patient for additional procedures. 
       SUMMARY 
       [0005]    In accordance with one embodiment, a surgical stapling and cutting device is constructed with a knife safety lockout element to prevent a knife element from cutting tissue if staples cannot be applied first to the tissue prior to being cut. The surgical stapling and cutting device comprises of a staple holder for holding a staple cartridge, an anvil movably coupled to the staple holder for opposing and deforming staples, a knife safety lockout element for blocking a knife element from being deployed, and a safety spring element for activating or biasing the knife safety lockout element into an active state to block the knife element from being deployed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  illustrates examples of linear cutters and stapling systems. 
           [0007]      FIG. 2A  through  FIG. 2C  illustrate an example of a jaw assembly of a linear cutter and stapling system. 
           [0008]      FIG. 3A  illustrates an opened jaw assembly of a linear cutter and stapling system. 
           [0009]      FIG. 3B  illustrates a close-up view of an opened jaw assembly of a linear cutter and stapling system. 
           [0010]      FIG. 4A  through  FIG. 4C  illustrate a safety lock-out mechanism for a surgical knife of a linear cutter and stapling system. 
           [0011]      FIG. 5A  through  FIG. 5D  illustrate a safety lock-out mechanism for a surgical knife of a linear cutter and stapling system. 
           [0012]      FIG. 6A  through  FIG. 6D  illustrate a safety lock-out mechanism for a surgical knife of a linear cutter and stapling system being deactivated by a staple cartridge. 
           [0013]      FIG. 7A  and  FIG. 7B  illustrate a safety lock-out mechanism being deactivated. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    In the following detailed description, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. Alternatively, some of the well-known parts, component, hardware, methods of operations, and procedures may not be described in detail or elaborated so as to avoid obscuring the present invention; but, nevertheless, they are within the spirit and scope of the present invention. 
         [0015]    A linear cutter is a surgical instrument that staples and cuts tissue, such as gastrointestinal tissue or other tissues of a patient. The linear cutter staples and cuts the target tissue such that the cut portions of the transected tissue are hemostatic. A typical linear cutter holds a disposable single-use staple cartridge with several rows of staples held within it, and it usually includes an anvil to oppose the staples as they are deployed from the staple cartridge. During a surgical operation, such as a minimally invasive procedure, the surgeon inserts the linear cutter through an opening in the body, orients the end of the linear cutter around the target tissue to be transected, maneuvers the jaw of the linear cutter until the target tissue is in-between the open jaw, and compresses the anvil and staple cartridge together to clamp that portion of the tissue to be cut. Then, a row or rows of staples are deployed on either side of the transection line, and a blade is advanced along the transection line to divide or cut the tissue. Since the divided or cut portions of the tissue were stapled, they are hemostatic after the cut. 
         [0016]    During actuation of a linear cutter, the staple cartridge typically fires all of the staples that it holds. In order to deploy more staples, the linear cutter must be moved away from the surgical site and removed from the patient, after which the old cartridge is exchanged for a new cartridge. The linear cutter is then reinserted into the patient with a new staple cartridge for additional stapling and cutting as required by the surgical procedure. 
         [0017]    As can be appreciated from the above discussion, stapling a target tissue to be transected prior to cutting the tissue avoids internal bleeding, which can facilitate the surgical procedure as the surgeon would not have deal with bleeding tissue. In addition, sealing or stapling the tissue prior to cutting may reduce trauma to the tissue as well as possibly expedite the healing and recovery process to the transected tissue, which may lead to long term positive outcome for the surgical operation. As such, the knife should not be deployed when a staple cartridge is not properly loaded in the linear cutter for staple deployment, become dislodged, missing, spent, or empty. To address this issue, Cardica, Inc. (“Cardica”) of Redwood City, California, has developed a safety lockout to prevent deployment of the knife when the staple cartridge is dislodged, missing, spent, or empty. 
         [0018]      FIG. 1  illustrates an example of linear cutter  100 , such as the MicroCutter XChange™  30  that is designed and manufactured by Cardica, Inc. (“Cardica”) of Redwood City, Calif. Typically, the linear cutter  100  includes a handle assembly  102  and a shaft assembly  104 . The handle assembly  102  usually includes various trigger and drive mechanisms for deploying staples and knife to staple and cut tissues. The shaft assembly  104  usually includes mechanisms and components for delivering and deploying the staples and knife at the point of action to staple and cut tissues. For example, the shaft assembly  104  typically includes a jaw assembly  200 , illustrated in  FIG. 2A  through  FIG. 2C , at the distal portion of the shaft assembly  104  that acts directly on the tissue to be stapled and cut. The jaw assembly  200  typically includes an anvil  202  that is movably coupled to a staple channel or staple holder  204 . The staple channel  204  typically holds a staple cartridge (not shown) that stores and deploys staples. The staples are deployed by one or more wedges  604  in a wedge assembly  602  (shown in  FIG. 6A  through  FIG. 6D ). The anvil  202  acts in concert with the staple holder  204 , with a loaded staple cartridge in the staple holder, the linear cutter clamps the target tissue, and then staples and cuts the target tissue upon activation of the trigger element and various mechanisms in the handle assembly  102 . 
         [0019]      FIG. 3A  and  FIG. 3B  illustrate close-up views of the jaw assembly  200  in an open-jaw orientation. In this open-jaw orientation, the knife  302  for cutting tissue and the safety lockout element  304  are visible inside the open-jaw of the stable holder  204 .  FIG. 4A  through  FIG. 4C  provide illustrations of isolated elements of the knife  302  and safety lockout elements (e.g., knife safety lockout  304  and safety spring element  306 ). As can be appreciated from these figures, the knife safety lockout element  304  may be biased by the safety spring element  306  to an orientation or position that is substantially in front of the knife  302 . In this manner, the knife safety lockout element  304  is directly in the path of travel for the knife  302 , which prevents it from being deployed to cut and transect tissue. The knife safety lockout element  304  may be biased substantially in a horizontal direction or plane to prevent the knife  302  from being deployed. Similarly, the knife safety lockout element  304  may be biased substantially in a diagonal direction or plane. Alternatively, the knife safety lockout element  304  may be biased substantially in a vertical direction or plane. As one example, the biasing of the knife safety lockout element  304  by the spring element  306  may be analogous to that of a gate or door being swing substantially horizontally to place the knife lockout element  304  to an active state. Alternatively, biasing the knife safety lockout element  304  in an opposite direction may place the lockout element  304  in a neutral state. In one example, the spring element  306  may be a sheet spring element, a leaf spring element, or a rod spring element. In another example, the spring element  306  may be a coil spring element or a torsional spring element. To be discussed further, the knife safety lockout may be biased away from the front of the knife  302  and out of its path of travel during operation.  FIG. 5A  illustrates a close-up top view of the knife safety lockout element  304 .  FIG. 5B  illustrates a further close-up top view of the knife safety lockout element  304  in relation to the knife  302  and safety spring element  306  to provide a better understanding of their orientations and interactions.  FIG. 5C  illustrates an isometric view or perspective view of the surgical knife element  302 , the knife safety lockout  304 , and the safety spring element  306 .  FIG. 5D  illustrates a even further close-up top view of the knife safety lockout element  304  in relation to the knife  302  and safety spring element  306  to provide a clearer illustration of their orientations and interactions. As clearly shown in these figures, the safety spring element  306  provides the necessary force to bias or push the safety lockout element  304  in front of the knife element  302  blocking its path of travel such that the knife  302  cannot be deployed. As can be appreciated from the figures, the safety lockout  304  is pushed or biased in front of the knife  302  when the staple cartridge is missing or dislodged. To be discussed further, the safety lockout  304  is pushed or biased in front of the knife  302  after the staples held in the staple cartridge are deployed and the knife  302  is reset to its initial or ready position. To be more clear, once some (one or more) of the staples have been deployed, resetting the knife to its initial or ready position will activate the safety lockout  304  and prevent the knife  302  from moving or advancing to be deployed and cut tissue. As such, the knife safety lockout element  304  prevents the knife  302  from being deployed without having staples being deployed first and stapling the tissue that will be cut by the knife  302 . 
         [0020]      FIG. 6A  through  FIG. 6D  illustrate engagement or placement of a staple cartridge  600  to the staple holder  204  which will deactivate the knife safety lockout  304 . More specifically, the wedge assembly  602  may deactivate the knife safety lockout  304 . For example, the wedge assembly  602  will push against the knife safety lockout element  304  and the safety spring element  306  to overcome the spring force of the safety spring element  306  to place the knife safety lockout element  304  in a neutral position away from or out of the path of travel of the surgical knife element  302 . In another example a different element or assembly of the staple cartridge  600  may deactivate the knife safety lockout element  304 . Typically, the wedge assembly  602  and wedges  604  are used to deploy the staples in the staple cartridge  600  loaded into the staple holder  204  of the jaw assembly  200  at the distal portion of the shaft assembly  104  of the linear cutter  100 . 
         [0021]    During operation of the linear cutter  100 , a surgeon operates the linear cutter  100  by activating the trigger element  106  of the handle assembly  102  to place the linear cutter  100  in a “trocar mode”. In the trocar mode, the end effector (e.g., the jaw portion of the shaft assembly  104 ) is at its smallest cross-sectional diameter for insertion through a substantially small opening. For example, the surgeon inserts the shaft of the linear cutter  100 , through a small cut- out opening, a port, or a trocar, into a cavity of a patient. The surgeon then maneuvers the distal portion or end effector of the linear cutter  100 , and places the jaw of the linear cutter  100  near the target tissue for the stapling and cutting of the tissue. The surgeon opens the jaw and clamps the target tissue between the anvil member  202  and the cartridge/staple holder  204  of the jaw assembly. The surgeon then further operates the trigger element  106 , which drives the gears, pulleys, other components, etc. in the handle assembly  102  and shaft assembly  104  to advance the wedge assembly  602 , wedge elements  604 , and surgical knife element  302  to staple and cut the target tissue. As should be noted, the wedge assembly  602 , more specifically the respective wedge elements  604 , advances against each of the staples for deployment. For example, a wedge element  604  advances against a staple and pushes it to an upwardly arch motion toward a staple forming pocket  206  in the anvil  202 , while frangibly separating the staple. The anvil  202  opposes and deforms the staple in the staple forming pocket  206 . 
         [0022]    During staple deployment and cutting of target tissue, the knife element  302  advances behind the wedge assembly  602  as one or more wedges  604  deploys the staples in the staple cartridge and the knife element  302  cuts the tissue along a transection line after the tissue is stapled on either or both sides of the transection line. As the staple cartridge is loaded into the staple holder  204 , the wedge assembly  602  deactivates the knife safety lockout element  304  and places it in a neutral position. As both the wedge assembly  602  and knife element  302  are deployed in the stapling and cutting operation, the knife safety lockout  304  continues to be deactivated in a neutral position; first by the wedge assembly  602  and then by the body of the knife element  302 . The knife safety lockout element continues to be deactivated in its neutral position until the knife element  302  is reset back to its initial ready position. The wedge assembly  604 , on the other hand, remains in its deployed position or state. The wedge assembly  604  does not get reset; regardless if it has been partially or fully deployed. Instead, the staple cartridge with the partially or fully deployed or spent (empty) condition is replaced with a new or fully loaded staple cartridge. The new cartridge is loaded onto or into the staple holder  204 . The loading of the new cartridge deactivates the knife safety lockout element  304  and places it in a neutral position. Once again, the linear cutter  100  is ready to be fired to deploy staples and cut tissue. 
         [0023]      FIG. 7A  and  FIG. 7B  illustrate the side-views of a new cartridge having been loaded into the staple holder  204 , which deactivates the knife safety lockout element  304  and places in a neutral position away from the front of the surgical knife element  302  and out of it path of travel for cutting tissue as it is advanced following the wedge assembly  602 . 
         [0024]    While the invention has been described in detail, it will be apparent to one skilled in the art that various changes and modifications can be made and equivalents employed, without departing from the scope of the present invention. It is to be understood that the invention is not limited to the details of construction, the arrangements of components, and/or the method set forth in the above description or illustrated in the drawings. Statements in the abstract of this document, and any summary statements in this document, are merely exemplary; they are not, and cannot be interpreted as, limiting the scope of the claims. Further, the figures are merely exemplary and not limiting. Words such as “upper,” “lower,” “upward,” “downward”, “front”, “back”, “next to”, and the like are intended for the convenience of the reader and refer to the orientation and motion of parts on the printed page; they do not in any way limit the scope or application of the invention. Topical headings and subheadings, if provided, are for the convenience of the reader only. They should not and cannot be construed to have any substantive significance, meaning or interpretation, and should not and cannot be deemed to indicate that all of the information relating to any particular topic is to be found under or limited to any particular heading or subheading. Therefore, the invention is not to be restricted or limited. The present invention is intended to cover alternatives, modifications, and equivalents that may fall within the spirit and scope of the present invention as defined by the claims.