Abstract:
A surgical clip applier having an adjustable jaw open dimension, including an instrument body having jaws at a distal end and an actuator at a proximal end; an actuator shaft movable longitudinally relative to the instrument body to transmit actuating force from the actuator to the jaws; and an adjusting member threadedly engaged with the actuator shaft and configured to engage the instrument body at a jaw open position, wherein rotation of the adjusting member relative to the actuating shaft moves the adjusting member longitudinally relative to the actuating shaft to adjust a jaw open position of the jaws when the adjusting member contacts the instrument body.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to a surgical clip applier and, more particularly, to a surgical clip applier for use in minimally invasive procedures and having an adjusting mechanism for adjusting the dimension of the jaws of the applier in the open dimension. 
         [0002]    The open position of a clip applier, especially a clip applier for minimally invasive surgical (MIS) procedures, is a critical aspect of the device. When the jaws open, if they open too much, a clip may not be firmly held between the jaws and could fall out of the appliers into the surgical site. On the other hand, if the jaws do not open wide enough, then clip loading can be difficult or impossible, and the clip may not load correctly, which could also lead to problems with placement and/or application at the surgical site. 
         [0003]    Based upon the above, it is clear that the need exists for an improved structure for more reliably setting the correct open position of an MIS clip applier. 
       SUMMARY OF THE INVENTION 
       [0004]    In accordance with the present invention, an MIS clip applier is provided which has an adjustment mechanism for producing the correct open dimension in a jaw open position thereby ensuring that the open dimension of the clip applier will securely hold clips without being too tight. This in turn allows for much more reliable placement of clips during MIS procedures. Further, the adjustment mechanism remains adjustable throughout the life of the instrument, which is particularly useful in addressing any wear or mistreatment to the instrument during the course of its use. 
         [0005]    In accordance with a further feature of the present invention, the adjustable mechanism is designed such that a non-standard tool is required to make any adjustments, and in this way the adjustment mechanism is prevented from being altered by an unskilled or unintended operator, and the adjustment mechanism is also adapted to prevent unintentional migration. 
         [0006]    The surgical clip applier in accordance with the present invention includes an instrument body having jaws at a distal end and an actuator at a proximal end; an actuator shaft movable longitudinally relative to the instrument body to transmit actuating force from the actuator to the jaws; and an adjusting member threadedly engaged with the actuator shaft and configured to engage the instrument body at a jaw open position, wherein rotation of the adjusting member relative to the actuating shaft moves the adjusting member longitudinally relative to the actuating shaft to adjust a jaw open position of the jaws when the adjusting member contacts the instrument body. 
         [0007]    A clear advantage of the inventive design is that it fully addresses the challenge of getting the correct jaw opening dimension, which is a very complicated procedure due to the tolerance stack up in all the components in the actuating mechanism. In other words, since the jaw opening and closing mechanism utilizes a series of components, and each component will have mechanical tolerance, the proper full open position of the device is complicated due to each of the mechanical tolerances of each of these components. With the present adjustment mechanism, the inventive MIS clip applier can be precisely adjusted despite such tolerances to the proper open dimension. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    A detailed description of preferred embodiments of the present invention follows with reference to the attached drawings, wherein: 
           [0009]      FIG. 1  is a sectional view of a surgical clip applier in accordance with the present invention in an open jaw position taken along the lines A-A of  FIG. 2 ; 
           [0010]      FIG. 2  is a side view of a surgical clip applier in accordance with the present invention in the open jaw position; 
           [0011]      FIG. 3  is a sectional view of a surgical clip applier in accordance with the present invention in a closed jaw position and taken along the lines of B-B of  FIG. 4 ; 
           [0012]      FIG. 4  is a side view of a surgical clip applier in accordance with the present invention in the closed jaw position; 
           [0013]      FIG. 5  is an enlarged view of the proximal components of the adjustment mechanism of a surgical clip applier in accordance with the present invention, in the open jaw position; 
           [0014]      FIG. 6  is an enlarged view of the proximal components of the adjustment mechanism of a surgical clip applier in accordance with the present invention, in the closed jaw position; 
           [0015]      FIGS. 7-9  further illustrate an embodiment of an adjustment knob in accordance with the present invention; and 
           [0016]      FIG. 10  illustrates an embodiment of an adjustment tool in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The invention relates to a surgical clip applier, especially a surgical clip applier designed for use in minimally invasive surgery (MIS) wherein the clip applier is to be positioned to a surgical site through a laparoscopic cannula. 
         [0018]      FIG. 1  shows a surgical clip applier  10  in accordance with the present invention. Applier  10  has jaws  12  at a distal end  14  and an actuator assembly  16  at a proximal end  18 . An instrument body  20  extends between proximal end  18  and distal end  14  and is advantageously an elongate, hollow and substantially rigid structure. Jaws  12  are pivotally mounted at distal end  14 , for example around a pivot pin  22 . 
         [0019]    Actuator assembly  16  in the illustrated embodiment has two levers  24  which are pivotally mounted relative to body  20 , for example at pivot points  26 . 
         [0020]    An actuator shaft  28  is slidably positioned within body  20  and extends from actuator assembly  16  to jaws  12 . Shaft  28  is connected to jaws  12 , preferably through links  30  pivotally connected through jaws  12 , such that longitudinal translation of shaft  28  within body  20  opens and closes the jaws. 
         [0021]    At proximal end  18 , shaft  28  is operatively associated with levers  24 , in this embodiment through a link  32 . Link  32  is pivotally connected to one lever  24  at one end, and to shaft  28  at the other end. As will be further discussed below, opening and closing of levers  24  relative to body  20  moves link  32  and, thereby, actuator shaft  28 , as desired. A closing of levers  24  moves shaft  28  proximally relative to body  20 , which positions jaws  12  into the closed position. (See  FIGS. 3 and 4 ). Opening of levers  24  relative to body  20  causes a distal movement of actuator shaft  28  relative to body  20 , thereby causing an opening of jaws  12  ( FIGS. 1 and 2 ). 
         [0022]    Referring also to  FIGS. 5 and 6 , the adjustment assembly in accordance with the present invention is further illustrated, and this assembly acts to create an adjustably-positioned stop position such that when levers  24  are opened relative to body  20 , jaws  12  will open to the correct dimension. 
         [0023]    The adjusting assembly in accordance with the present invention is preferably a threaded adjustment knob  34  which is threadedly engaged with a proximal end of actuator shaft  28 . Adjustment knob  34  has additional structure, in this case a distally extending sleeve  36  which extends radially outwardly from shaft  28 , to engage against body  20  in the fully open position ( FIG. 5 ). As shown in  FIG. 5 , body  20  can include a proximally positioned end body  38  having an internal bore for accommodating a proximal end of shaft  28  and adjustment knob  34 . As shown in  FIG. 5 , end body  38  also has rounded outer surfaces for pivotally receiving levers  24  at pivot points  26 . 
         [0024]    From a consideration of  FIGS. 2 ,  4  and  5 - 6 , it should be appreciated that end body  38  creates a recessed area for receiving adjustment knob  34  such that adjustment knob  34  is shielded from unintentional contact or adjustment. 
         [0025]    It should be appreciated that adjustment knob  34  is rotated so as to change position of knob  34  relative to shaft  28  in the course of adjusting the desired exact position of knob  34  to produce the proper open dimension in the jaw open position. Thus, it is necessary to rotate adjustment knob  34  during adjustment of the device. In accordance with a further aspect of the present invention, and in order to prevent unauthorized or unskilled adjustment of adjustment knob  34 , knob  34  is advantageously provided with a non-standard engagement structure. In other words, knob  34  is provided with structure for engaging with a tool, but which is preferably not a typical screwdriver or Allen wrench type engagement structure. Further, a corresponding or matching tool adapted for engagement with knob  34  is advantageously provided with applier  10  so that skilled and intended persons can adjust knob  34  as desired. 
         [0026]    In further accordance with this aspect of the invention it should again be appreciated that recessed bore  40  of end body  38  is sufficiently deep that knob  34  is completely received within recessed bore  40 , preferably with no portion of knob  34  extending beyond end body  38 . Further, and as best illustrated in  FIGS. 2 and 4 , end body  38  can also have a proximally concave structure to further assist in preventing any unintended contact with adjustment knob  34 . 
         [0027]    Still referring to  FIGS. 5 and 6 , a spring  42  can be positioned within end body  38  such that it exerts a biasing force in a distal direction against a shoulder  44  of shaft  28 , and in a proximal direction against a shoulder or other structure  46  of end body  38 . In this manner, spring  42  serves to bias shaft  28  in a distal direction and keep knob  34  engaging against stop surface  48  of end body  38 . In this way, when levers  24  are released or opened, spring  42  ensures that knob  34  through shaft  28  positioned jaws  12  into the desired and exactly adjusted open dimension. 
         [0028]    As shown in  FIG. 6 , when levers  24  are compressed to close jaws  12 , shaft  28  moves proximally along with knob  34  which moves proximally a small distance away from stop surface  48 . When levers  24  are released, these components move back to the position of  FIG. 5 . 
         [0029]    In accordance with a further aspect of the present invention, adjustment knob  34  is preferably axially slotted to produce a spring effect on the threaded engagement with the actuator shaft  28 . This helps to prevent knob  34  from migrating unintentionally relative to shaft  28  and, thereby, altering the fine adjustment of applier  10 . This mechanism operates in a similar manner to a standard lock washer, wherein the slot causes the material to act like a spring and maintain constant pressure and friction between knob  34  and shaft  28 , which helps to prevent any relative movement of these components. 
         [0030]      FIGS. 7-9  illustrate further features of an adjustment knob  34  in accordance with the present invention. As shown, adjustment knob  34  has a proximal end  50  and a distal end  52 , as well as a threaded internal surface  54  for engaging with shaft  28 . As shown in these drawings, proximal end  50  has non-standard structure for engaging with a tool, and this structure, in this embodiment, is provided in the form of two spaced holes or sockets  56 . Sockets  56  are engaged with an adjustment tool as will be discussed further below when it is needed to rotate adjustment knob  34  relative to shaft  28  and thereby adjust the axial position of knob  34  relative to shaft  28 . 
         [0031]    Still referring to  FIG. 7-9 , adjustment knob  34  can advantageously have a slot  58  through the sidewall of knob  34 , preferably extending from a circular opening  60  to distal end  52  as shown. This slotted structure, coupled with sizing of internal thread  54  to have a compression fit on the threads of shaft  28 , serves to provide a spring interaction between knob  34  and shaft  28  to help prevent unintended rotation of knob  34  relative to shaft  28 .  FIGS. 7 and 8  are shown rotated  90  degrees from each other around the longitudinal axis of knob  34  and have dashed lines to better illustrate the internal structure of slot  58 , openings  60  and sockets  56 . 
         [0032]      FIG. 9  is an end view of knob  34  and further illustrates the two spaced sockets  56  which are used to engage knob  34  with a specialized adjustment tool as will be discussed below. 
         [0033]      FIG. 10  shows an adjustment tool  62  which is designed specifically for use with knob  34  when knob  34  is to be rotated to adjust its position and, thereby, the width of the opening of jaws in a full open position. 
         [0034]    As shown, tool  62  can have a handle portion  64  and a tool portion  66 . Tool portion  66  preferably has two extending prongs  68  which are sized and spaced to match with sockets  56  of knob  34 . Thus, when tool  62  is to be used to engage knob  34 , prongs  68  are inserted into sockets  56  to allow secure engagement of tool  62  with knob  34  and appropriate rotation of same. 
         [0035]    Tool  62  can also be provided with one or more gap setting structures as shown at  70  and  72 . These structures  70 ,  72  can be provided as two spaced indentations  74 ,  76 , which are sized to accommodate the tips of the jaws of the applier. Indentations  74 ,  76  are spaced on tool  62  at the correct spacing of jaws for particular sizes of clips. In the embodiment shown in  FIG. 10 , indentations  74  are set to the proper width for a medium clip, and indentations  76  are set to the proper width of a small clip. Tool  62  also has indicia in close proximity to close proximity to indentations  74 ,  76  to convey this information to the user of tool  62 . It should be appreciated that tool  62  having different spaced indentations  74 ,  76  advantageously serves to allow tool  62  to easily adjust a clip applier to both sizes of clips. 
         [0036]    In use, tool  62  could be used to position jaws at the proper width by matching the jaws to indentations  74 ,  76  as desired, and then engaging tool  62  with knob  34  to rotate the knob into contact with surface  48  of end body  38 . Once knob  34  is appropriately positioned, indentations  74 ,  76  can then be again matched to the jaws of the device in the full open position to confirm that the applier is properly adjusted. 
         [0037]    It should be appreciated that while, in this embodiment, the sockets and prongs of knob  34  and tool  62  are one embodiment of a non-standard tool for use in providing authorized adjustment of the applier, the specific non-standard structures could be provided in different ways, with different shapes and numbers of sockets and prongs, and/or with prongs and sockets on the opposite member as well. Nevertheless, it is preferred to have the sockets be in knob  34  as this helps keep a low profile of knob  34  within the applier, and thereby helps to reduce the possibility of inadvertent contact and movement of the knob. 
         [0038]    It is to be understood that the invention is not limited to the illustrations described and shown herein, which are deemed to be merely illustrative of the best modes of carrying out the invention, and which are susceptible to modification of form, size, arrangement of parts and details of operation. The invention, rather, is intended to encompass all such modifications which are within its spirit and scope as defined by the claims.