Abstract:
A surgical instrument includes a hollow shaft having an inner passage and a working piece at the distal end of the shaft. A movable member is pivotally mounted on the shaft in cooperative relationship to the working piece and a connecting element extends along the shaft inner passage and has one end exiting thorough an opening in said shaft and connected to the movable member. An actuating member is connected to the connecting element which upon actuation pushes and pulls on the connecting element to move the movable member toward and away from the working piece. An ultrasonic transducer can supply mechanical energy to the shaft to vibrate the working piece, the movable member is mounted to the shaft at a nodal point of the energy pattern along the shaft and the opening in the shaft for exit of the connecting element to the movable member is also at a nodal point.

Description:
RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of application Ser. No. 08/730,851, filed Oct. 17, 1996, which in turn is a continuation-in-part of application Ser. No. 08/685,700, filed Jul. 14, 1996, now abandoned, both of which are assigned to the assignee of the subject application. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    In the foregoing applications novel surgical scissor instruments are disclosed. The preferred embodiments of the instruments disclosed include a handpiece containing an ultrasonic transducer operative to convert electrical energy into ultrasonic longitudinal vibratory motion. Extending from the handpiece is an elongate portion including a fixed outer tubular member depending from the handpiece. An inner shaft is located in the fixed outer tubular member for reciprocating movement relative to the fixed outer tubular member. A proximal end portion of the inner shaft is operatively connected to the transducer for causing the inner shaft to longitudinally vibrate.  
           [0003]    A first cutting member is fixedly mounted to the distal end of the inner shaft and extends from the distal end of the outer tubular member. Longitudinal vibratory motion generated by the transducer affects corresponding longitudinal vibratory motion of the first cutting member, via the inner shaft. A second cutting member is connected to the inner shaft and is pivotable between an open and closed position with respect to the vibrating first cutting member. A second shaft has a first end pivotally connected to the second cutting member for affecting pivotable movement of the second cutting member between the open and closed positions.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention is directed to improvements in various types of surgical instruments. In accordance with the invention, a hollow shaft is provided which has a working piece, such as a cutting blade, at its distal end. In the case of the instrument being of the ultrasonic type, the proximal end of the hollow shaft receives mechanical energy from an ultrasonic transducer to vibrate the working piece. Such a transducer can be of the piezoelectric or magnetostrictive type. For the latter, a coil of wire receiving electrical energy of a predetermined frequency energizes a stack of laminations. An acoustically tuned connecting body converts the vibrations of the lamination stack into mechanical energy that is conveyed along the length of the shaft to the working piece at the distal end.  
           [0005]    In the preferred embodiment, a member is mounted outside of the shaft which is movable relative to the shaft distal end working piece. In the case of the instrument being a scissors, the shaft distal end working piece is one blade and the movable member is the second blade. The movable member is actuated by a connecting element that extends through the inner passage of the hollow shaft and exits through an opening in the shaft to be attached to the movable member. In the case of the instrument being of the ultrasonic type, the movable member preferably is mounted at a nodal point of the mechanical energy that is transmitted along the length of the shaft and the exit opening for the connecting element preferably is also at a nodal point along the shaft. This minimizes the loss of energy to the working piece and also minimizes rubbing friction between the connecting element and the vibrating shaft at the opening.  
           [0006]    The instrument has only a single shaft which can be of a very small diameter and no external shafts are needed for the movable member. The principles of the invention are adaptable both to ultrasonic and non-ultrasonic instruments.  
         OBJECTS OF THE INVENTION  
         [0007]    It is therefore an object of the invention to provide improved surgical instruments in which a hollow shaft has a working piece at its distal end and a movable member cooperating with the working piece is actuated by a connecting element extending through the shaft.  
           [0008]    Another object is to provide improved ultrasonic surgical instruments in which a hollow shaft vibrated by ultrasonic energy has a working piece at its distal end and a movable member, which is preferably mounted at a nodal point of the vibrating shaft, is actuated by a connecting element extending through an opening in the shaft, also preferably at a nodal point, and has a cooperating action with the shaft working piece.  
           [0009]    A further object is to provide a surgical instrument having a hollow shaft housing a plurality of working pieces that can be selected for use by one or more connecting elements extending in the shaft inner passage. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    Other objects and advantages of the present invention will become more apparent upon reference to the following specification and annexed drawings in which:  
         [0011]    [0011]FIG. 1 is a diagrammatic illustration of a vibratory surgical instrument in accordance with the subject invention;  
         [0012]    [0012]FIG. 2 is a perspective view of a handle assembly used with the surgical instruments of the invention;  
         [0013]    [0013]FIG. 3 is an enlarged view of the operative end of an embodiment of an instrument in accordance with the invention;  
         [0014]    [0014]FIGS. 4A and 4B are enlarged side and top views of the operative end of a further embodiment;  
         [0015]    [0015]FIGS. 5A and 5B are enlarged side and top plan views of the operative end of still a further embodiment of an instrument according to the invention;  
         [0016]    [0016]FIGS. 6A and 6B are an enlarged side view and an end view along line A-A of an embodiment of the invention in which working pieces are selected using a rotatable mount: and  
         [0017]    [0017]FIGS. 7A and 7B are an enlarged side view and an end view along line A-A of the operative end of an embodiment in which a working piece is selected by actuation of a connecting element. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]    Referring to FIGS.  1 - 3 , the principles of the invention are illustratively described with reference to an ultrasonic scissors  10 . The surgical instruments of the invention are intended to be implemented in a wide variety of surgical instrumentation, e.g., vascular, endoscopic, laparoscopic, etc.  
         [0019]    With reference to FIGS.  1 - 3 , the instrument  10  includes a handpiece  12  having a fixed outer tubular (hollow) shaft  14  extending distally therefrom. Shaft  14  has an inner passage  15 . While the outer shape of shaft  14  is shown as being cylindrical, it can be of any suitable shape, such as polygonal. It is also of any suitable material, for example, stainless steel. A working member  16 , such as one blade of a pair of cooperating scissor blades, is located at the distal end of tubular shaft  14 . The working piece  16  can be integrally formed as part of the shaft, such a by machining, or it can be a separate piece that is fastened, such as by welding, to the shaft.  
         [0020]    The proximal end of shaft  14  is attached to a handpiece  12  which houses or receives energy from a transducer  18 , such as an ultrasonic transducer, to be supplied to the shaft. The transducer  18  comprises any suitable means for converting electrical energy into mechanical longitudinal vibration. For example, the transducer  18  may be of the conventional piezoelectric or magnetostrictive type. The latter has a stack of laminations of a suitable material, such as Nickel. The laminations are connected together at the proximal end of the handpiece  12  and are connected at the stack distal end to one end of an acoustic impedance transformer  17 . A wire coil surrounds the lamination stack and supplies electrical energy at a predetermined frequency that is induced in the lamination stack which converts the electrical energy to mechanical energy. The acoustic impedance transformer is a body of metal of suitable shape and thickness necessary to convert the vibrations of the laminations into longitudinal motion. The other end of the acoustic impedance transformer is attached to the proximal end of the hollow shaft  14  for providing longitudinal vibratory motion that is conveyed to the working piece  16 . A magnetostrictive type transducer is described in greater detail in commonly assigned U.S. Pat. No. 5,417,203, the disclosure of which is hereby incorporated by reference.  
         [0021]    As shown diagrammatically in FIG. 1, a movable member  20  is mounted, in a manner described below, for pivotal motion to cooperate with the working piece  16  at the distal end of shaft  14 . In the case of the instrument being a scissors, member  20  is a second scissors blade. The member  20  is moved by a flexible connecting element  22  that extends along the length of the shaft  14  inner passage  15 , exits through an opening  60  in the shaft and is connected to member  30  at a point  62 . The connecting element  22  is moved in a reciprocating manner by an actuating mechanism  28 , described below. The connecting element  22  is of any suitable type and material. For example, it can be a cable or rod of metal or plastic, that is flexible at least at the end exiting from shaft opening  60  and is capable of transmitting force from the actuating mechanism  28  to the movable member  20  upon the connecting element  22  being moved in either direction, that is either pulling on element  22  or pushing it. The diameter of connecting element  22  is selected relative to the diameter of the shaft inner passage  15  and exit opening  60 .  
         [0022]    Referring to FIG. 2, actuating mechanism  28  is shown as incorporated in a handpiece  12  having a manually operated handle assembly  40  including a fixed handle  42  and a pivoting handle  44 . Within a cavity of the handle assembly  40 , the proximal end portion of the reciprocating connecting element  22  is operatively connected to pivoting handle  44 . Reciprocating motion of pivoting handle  44  by the user of the instrument affects corresponding reciprocating longitudinal motion of connecting element  22  relative to tubular shaft  14  and back and forth motion of movable member  20  relative to the working piece  16 .  
         [0023]    The transducer  18  can be mounted within the cavity of handpiece  12  with electrical connection to an outside electrical source. In this case, a plug member  46  extending from the handpiece  12  provides electrical energy to the transducer. Alternatively, the transducer  18  can be outside of the handpiece  12 . For example, the remote transducer would have a vibrating output shaft which would enter the handpiece  12 , such as at point  46 , and extend along its length to exit as the shaft  14 , as shown.  
         [0024]    As is known, the ultrasonic vibratory energy transmitted along the length of the shaft  14  is at a frequency determined by a variety of factors such as, for example, shaft material, dimensions, shape, etc. Located along the length of the shaft are one or more nodal points, that is points at which the amplitude of the vibratory energy is zero, or substantially close thereto. The location of the nodal points correspond to the fundamental frequency and harmonics, principally the second, of the energy propagated along the shaft length. The nodal points can be determined by appropriate design and analysis in accordance with well known principles of ultrasonic technology.  
         [0025]    [0025]FIG. 3 shows in detail the distal end of one form of the instrument. The working piece  16  at the distal end of the shaft is shown as a straight blade, but it also can be a saw or a clamp. The working piece  16  is vibrated longitudinally by the ultrasonic energy. The movable member  20  is illustratively shown as a scythe shaped blade whose proximal end is pivotally mounted to the shaft  14  on a pivot member  50 . The pivot member may be of any suitable type. It is preferred that the pivot  50  be located at a nodal point of the energy along the shaft. Where the member  20  is a single blade, the pivot  50  can be a stud on the outer surface of the shaft and member  20  is slightly offset relative to the working piece  16 .  
         [0026]    The end portion of connecting element  22  remote from handle  44  extends through an opening  60  in shaft  14 . The opening  60  preferably is also at a nodal point of the shaft and can be at the same nodal point as the pivot  50 . The distal end of connecting element  22  is connected to the movable member  20  at point  62 . By placing each of the pivot mount  50  and the connecting element exit opening  60  at a nodal point along the length of shaft  14 , little or no energy is lost by transfer to the pivot mount  50  or connecting element  60 . Also, this minimizes rubbing friction between the connecting element  22  and the vibrating shaft  14 .  
         [0027]    By the user operating the actuating mechanism  28 , that is, by reciprocating the pivotal handle  44 , the connecting element  22  is moved in a reciprocating manner within the shaft causing the movable member  20  to open and close in an arcuate manner relative to the longitudinally vibrating working piece  16 . This causes a cutting action to take place of any object, such as tissue, between elements  16  and  20 .  
         [0028]    Since shaft  14  is vibrating, as shown in FIG. 3, a protective sleeve  70  is preferably placed around the shaft  14  for a part of its length up to the distal end to protect the user from any heat built up on the shaft. Sleeve  70  can be of any suitable material, for example, TEFLON, KYNAR, etc.  
         [0029]    [0029]FIGS. 4A and 4B show another embodiment of the invention wherein the same reference numbers are use for the same components previously described. Here, the working piece  16  at the distal end of the shaft  14  is shown as a saw type blade, although any suitable cutting instrument, or clamp, can be used. A pair of pivot mounting studs  50   a  are fastened, such as by welding, to the outer surface of the shaft  14 , preferably at a nodal point. The studs  50   a  preferably lie along a diametrical line through the shaft. The movable member is formed by a pair of spaced curved arms  20   a , which can be blades or clamp members. Each of the arms  20   a  has its proximal end pivotally mounted to a respective one of the studs  50   a . A cross-piece  30  connects the two movable arms  20   a . The end of connecting element  22  which protrudes from the shaft opening  60 , which also preferably is at a nodal point, is connected to the cross-piece  30 . The cross-piece  30  either can overlie the shaft, as shown, or it can overlie the working piece  16 .  
         [0030]    The operation of the instrument of FIGS.  4 A- 4 B is as previously described. That is, when the user actuates the instrument pivotal handle  44 , the connecting element  22  is longitudinally reciprocated within the shaft passage to move the cross-piece  30  and thereby move the two arms  20   a  about the pivots  50   a  back and forth relative to the working piece  16 . If the arms  20   a  are clamp members, they hold the object being operated on against the vibrating working piece  16  to cut the object.  
         [0031]    [0031]FIGS. 5A and 5B show a further embodiment of the invention which is similar to that of FIGS. 4A and 4B in the use of the twin movable arms  20   a  connected by the cross-piece  30 . Here, an extender  54  is connected to each of the pivot mounting studs  50   a  and extends proximally of the shaft. As explained above, the studs  50   a  preferably are mounted at a node of the energy with respect to the shaft. Thus, no energy is transmitted to an extender  54 . Each extender  54  is shown as being generally circular in shape, although any other shape can be utilized. As shown, each of the arms  20   a  is pivotally mounted to an extender  54  at pivot point  57 . The extenders  54  permit the configuration of the movable member  20   a  to be more varied in shape and also can provide greater leverage for the reciprocating operation of the arms  20   a  by the connecting element  22 .  
         [0032]    The operation of the instrument of FIGS.  5 A- 5 B is the same as that described with respect to FIG. 4.  
         [0033]    [0033]FIGS. 6A and 6B show a further embodiment of the invention in which a head  80  is rotatably mounted at the distal end of shaft  14 . The head has a plurality of different types of cutting implements  84  spaced around its outer surface. Four such implements are shown spaced apart by 90°, although any suitable number of implements of any suitable type and shape, can be spaced around at any suitable angular orientation. A protective cover  86  has an end  87  connected to shaft  14 , also preferably at a nodal point. The cover extends over the head  22  and permits exposure to an operative position of only one of the implements  84 .  
         [0034]    The mount  82  for the head  80  to the end of the shaft  14  is preferably of the rotatable detent type. The mount  82  has a mechanism which is actuated by the connecting element  22  when the user actuates the pivotal handle member  44 . The mechanism converts the linear pulling or pushing motion of the connecting element  22  produced by actuating handle  44  into rotational motion of the head  80 . Thus, for example, each pull (or push) of the handle  44  will rotate head  80  by one detent stop to expose a different implement  84  through the protector  86 . If the instrument is of the ultrasonic type, the head  80  and the working implements will be vibrated longitudinally and the exposed implement  84  will be available to achieve a cutting action.  
         [0035]    If desired, in the embodiment of FIG. 6, a second connecting element can be passed through the shaft and a movable member  20 , such as shown in FIGS.  1 - 5 , can be attached to the shaft to be actuated by the second connecting element.  
         [0036]    [0036]FIGS. 7A and 7B show another embodiment of the invention in which there are a plurality of implements  84 , two such implements being illustrated, pivotally mounted at the end of the shaft  14 , which can be vibrating or stationary, on an axle  88 . A respective connecting element  22  is connected to each implement  84 . The handle  40  of FIG. 2 would have two triggers, one for each connecting element, or a trigger mechanism that can be selectively connected to a connecting element. Actuating a connecting element, by pulling it back away from the shaft distal end, causes the respectively connected implement  84  to rotate on axle  88  and extend outwardly of the shaft and be available for cutting action. Pushing on the connecting element retracts the respective implement  84  back into the shaft. Here also, the shaft  14  can be vibrated by energy from a transducer so that the exposed implement will have a cutting action. Here also, a movable member can be attached to the shaft  14  as previously described.  
         [0037]    It should be appreciated that the surgical instruments of the invention are compact, lightweight and easy to use. The instruments can be used with one hand, thus freeing the other hand for performance of other surgical tasks.