Abstract:
The surgical suturing instrument incorporates a pressurized fluid suture feed system for passing a suture through the instrument and the tissues to be joined thereby. A fluid jet in communication with a suture feed conduit selectively entrains a suture in a stream of pressurized fluid, which carries the suture through the instrument&#39;s hollow tissue penetrating needle. The tissue penetrating needle may be shaped to direct the suture&#39;s free end to a point external the body cavity. Alternatively, a suture return conduit may be provided to engage the hollow tissue penetrating needle to receive and carry the suture&#39;s leading end to a point external the body cavity. External or internal pressurized fluid sources are utilized. A surface irregularity proximal the suture&#39;s leading end enhances the entrainment of the suture with the fluid stream. Individual, cartridge and spool fed sutures may all be utilized.

Description:
TECHNICAL FIELD  
       [0001]     This invention relates to the field of suturing instruments used for stitching internal tissues of the body, such as in arthroscopic or endoscopic surgery. More particularly, the invention relates to a suturing instrument wherein the suture is fed through the instrument and the tissues to be joined by entrainment with a pressurized fluid. The preferred suture contemplated by the invention will have a surface irregularity to provide an enhanced frictional interface to facilitate entrainment in the fluid stream.  
       BACKGROUND OF THE INVENTION  
       [0002]     In the field of arthroscopic surgery various suturing instruments have been used  11  for stitching internal tissues of the body. An object of such surgical procedures is to minimize the invasiveness of the surgical instrument in performing a given surgical procedure, whether diagnostic or restorative. This object is achieved by making a small incision in the overlying tissue layers to provide the surgeon access the site of interest. The surgeon may then insert the surgical instrument through the small incision and perform the desired procedure.  
         [0003]     In many procedures, the surgeon will need to insert a stitch to join body tissues at the site of interest. A suturing instrument such as that disclosed by Caspari, et al., in U.S. Pat. No. 4,957,498, will typically be used for joining tissues internal a patient&#39;s body. Such suturing instruments provide a hollow tissue penetrating needle through which the surgeon feeds a length of suture material. The suture material is fed by manipulation of a thumbwheel. After insertion of the suture material through the tissues the free end of the suture material is withdrawn with the instrument through the incision to a point external the patient&#39;s body. The surgeon then knots the suture material and manipulates the suture material to urge the knot back through the incision to a point adjacent to the joined tissues.  
         [0004]     In practicing the invention disclosed by Caspari, the inventor has noticed the difficulty experienced by surgeons in manipulating the suture feed mechanism while maintaining the jaws of the instrument in the closed, tissue penetrating position. Moreover, the instrument disclosed by Caspari et al, requires the surgeon to coax the free end of the suture material to a point external the patient&#39;s body while at the same time feeding additional suture material by manipulation of the thumb wheel.  
         [0005]     Should the surgeon loose the free end of the suture material during retraction of the instrument, additional intrusion into the body cavity is necessary to retrieve the suture free end for tying the desired stitch. In addition, should the free end of the suture be inadvertently pulled free of the tissue penetration points, additional tissue insult may be necessary to reinsert the suture material through the tissues. Accordingly, there is a need for a suturing instrument that provides an improved suture material feed and retraction mechanism.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     It is an object of the invention contemplated herein to provide an improved suture material feed mechanism for a surgical suturing instrument. According to the present invention, a pressurized fluid source is utilized to entrain and selectively feed a suture through the instrument and the tissues to be joined thereby. The suturing instrument comprises a handle portion, an elongated tubular member extending from the handle portion and a hollow tissue penetrating needle attached to the elongate tubular member distal the handle portion. A suture feed conduit extends in fluid communication between the hollow tissue penetrating needle and a suture feed inlet proximal the handle portion. A fluid jet, proximal the handle portion selectively communicates a pressurized fluid through the suture feed conduit and tissue penetrating needle. The suture feed inlet receives a leading end of the suture such that it is positioned relative the fluid inlet jet for selective entrainment of the suture with the pressurized fluid.  
         [0007]     A preferred suture according to the present invention includes a surface irregularity, which defines a friction enhancing interface between the suture and the pressurized fluid. The surface irregularity is provided proximal a leading end of the suture and enhances the entrainment of the suture in the pressurized fluid stream. According to the present invention, the suture may be supplied to the instrument as an individual strand or as a plurality of sutures in a continuous strand. Each type of suture may be supplied on a spool or cartridge received by the instrument.  
         [0008]     Individual suture strands are provided at a predetermined length corresponding to a required penetration depth to stitch the site of interest and should also allow the free ends of the strand to remain external the body for the surgeon to easily tie and manipulate the knot to a point adjacent the tissues to be joined.  
         [0009]     A continuous strand of suture material has a plurality of surface irregularities spaced apart along its length. Each surface irregularity is spaced at a predetermined distance corresponding to a required penetration depth to stitch the site of interest and also allow the free ends of the strand to remain external the body for the surgeon to tie and manipulate the knot. A notch in the suture material adjacent a subsequent abrasion or protrusion is provided to facilitate separation of a delivered strand of suture material from the remaining strand of suture material.  
         [0010]     Since it is a further object of the invention to improve the extraction of the suture free end to a point external the body, the suturing instrument of the present invention provides for a suture material return path between the site of interest and the instrument entry incision. This is achieved by reversing the direction of the fed suture and directing it on a suture return path to a point external the patient&#39;s body via the instrument entry incision.  
         [0011]     In situations where a cannula is used to retract tissues overlying the site of interest open, the cannula opening may be used as the return path. In this instance, a hook shaped needle redirects the fed suture material outward the body. In situations where a cannula is not used, or where other organs or tissues may overly the site of interest, a return conduit is provided on the instrument to receive the leading end of the suture and carry it outwardly of the instrument entry incision. Positive reception of the suture material in the return conduit is provided by having the suture return conduit selectively engage with the tip of the tissue penetrating needle. Engagement of the return conduit with the tissue penetrating needle is provided by a lever or scissors assembly operable from the handle of the instrument.  
         [0012]     Additional objects and advantages of the invention will be realized by reference to the accompanying drawings and the detailed description of the drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     Various embodiments of my invention are depicted in the appended drawings which form a part of this disclosure and wherein:  
         [0014]      FIG. 1  is a side sectional view of a suture instrument with a tissue penetrating needle in an open position;  
         [0015]      FIG. 2  is a side sectional view of a suture instrument with a tissue penetrating needle in an open an a spooled suture feed;  
         [0016]      FIG. 3  is a side view of a suture instrument with a tissue penetrating needle in a closed position;  
         [0017]      FIG. 4  is a side sectional view of a suture instrument with a tissue penetrating needle in a closed position;  
         [0018]      FIG. 5  is a detail view of a sleeve actuated tissue penetrating needle closure with the needle in an open position;  
         [0019]      FIG. 6  is a detail view of a sleeve actuated tissue penetrating needle closure with the needle in an open position;  
         [0020]      FIG. 7  is a detail view of a lever actuated tissue penetrating needle closure with the needle in an open position;  
         [0021]      FIG. 8  is a detail view of a lever actuated tissue penetrating needle closure with the needle in an open position;  
         [0022]      FIG. 9  is a detail view of a scissors actuated tissue penetrating needle closure with the needle in an open position;  
         [0023]      FIG. 10  is a detail view of a scissors actuated tissue penetrating needle closure with the needle in an open position;  
         [0024]      FIG. 11  is a detail view of an extensible suture return conduit tissue penetrating needle closure with the needle in an open position;  
         [0025]      FIG. 12  is a detail view of an extensible suture return conduit tissue penetrating needle closure with the needle in an open position;  
         [0026]      FIG. 13  is a detail view of an open hook tissue penetrating needle;  
         [0027]      FIG. 14  is a side view of an abraided suture surface irregularity;  
         [0028]      FIG. 15  is a side view of a constriction suture surface irregularity;  
         [0029]      FIG. 16  is a side view of a protruding suture surface irregularity; and  
         [0030]      FIG. 17  is a side view of a compound suture surface irregularity.  
         [0031]      FIG. 18  is a partial side view of depicting a typical surgical procedure utilizing a hooked embodiment of the claimed suture instrument;  
         [0032]      FIG. 19A  is a side view of a suture spool;  
         [0033]      FIG. 19B  is a perspective view of a suture spool;  
         [0034]      FIG. 20A  is a perspective view of a suture cartridge;  
         [0035]      FIG. 20B  is a partial sectional view of a suture cartridge with a wound suture material in its pre-insertion condition;  
         [0036]      FIG. 20C . is a partial sectional view of a suture cartridge with a wound suture material in its inserted condition;  
         [0037]      FIG. 21A  is a partial sectional view of a suture cartridge with a folded suture  11  material in its pre-insertion condition;  
         [0038]      FIG. 21B . is a partial sectional view of a suture cartridge with a folded suture material in its inserted condition;  
         [0039]      FIG. 22  is a partial perspective view of a cartridge receiving suture instrument;  
         [0040]      FIG. 23  is a partial perspective view of a cartridge receiving suture instrument with a cartridge inserted;  
         [0041]      FIG. 24  is an end view of a suture instrument handle with an internal pressurized fluid source; and  
         [0042]      FIG. 25  is an end view of a suture instrument handle configured for an external pressurized fluid source. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0043]     In reference to the drawings, the suture instrument  10  of the present invention comprises a handle portion  20 , an elongated tubular member  30  extending from handle portion  20  and a hollow tissue penetrating needle  40  located at an end of elongated tubular member  30  distal handle portion  20 . The length of elongated tubular member  30  is selected to correspond with a desired penetration depth within a body to reach the tissues to be joined  11  by a suture  50 . The tissues to be joined  11  will also be referred to herein as site of interest. As is well known in the art, a cannula  12 , such as that depicted in  FIG. 18 , is often used to retract the tissues at the entry incision  13  and improves access to the site of interest  11  by retracting the tissues overlying the site of interest  11 . Cannula  12  will also perform a protective role for the overlying tissues by preventing undesirable instrument contact with the same. Accordingly, the length of elongated tubular member  30  must also account for any extension of canula  12  external the patient&#39;s body.  
         [0044]     Handle portion  20  is adapted to be received in the hand of a surgeon to facilitate  11  manipulation of the tissues at the site of interest and their suturing with instrument  10 . Handle portion  20  is depicted in the drawings substantially perpendicular to elongated tubular member  30 . However, this depiction is merely exemplary, as it is contemplated that more ergonomically advantageous handle configurations may be utilized for a particular surgical procedure or surgeon preference without departing from the scope of the present invention.  
         [0045]     In practice, the surgeon manipulates the instrument to position hollow tissue penetrating needle  40  at a desired penetration point and urges the needle tip  41  through the first tissue to be joined. The surgeon then manipulates the instrument to a desired penetration point on a second tissue to be joined and urges needle tip  41  through the second tissue. Depending on the needle tip configuration, examples of which are provided in  FIGS. 5-12 , the surgeon will manipulate a trigger  27 , such as that shown in  FIGS. 1-4 , or a conventional scissors assembly (not shown). Suture  50  may then be passed through the instrument and the tissues to be joined.  
         [0046]     In the prior art, the surgeon was required to continuously manipulate the instrument during delivery of suture  50  through the instrument. Similarly, the surgeon must manipulate the instrument to continue to deliver suture  50  while coaxing free end  51  to a point external the patient&#39;s body. The pressurized fluid suture delivery taught by the present invention eliminates the need to manipulate the instrument during suture  50  delivery through the tissues and subsequent passage of leading end  51  to a point external the patient&#39;s body.  
         [0047]     In the present invention, a suture feed conduit  31  extends between handle portion  20  and tissue penetrating needle  40 . A suture feed inlet  32  is provided at a first end of suture feed conduit  31  proximal handle portion  20 . Suture feed inlet  32 , suture feed conduit  31  and hollow tissue penetrating needle  40  define a suture delivery path. A fluid jet  33 , in communication with suture feed conduit  31 , selectively communicates a pressurized fluid through suture feed conduit  31  and hollow tissue penetrating needle  40 . Suture  50  is positioned to be entrained in the pressurized fluid stream for delivery through the tissues to be joined.  
         [0048]     Fluid jet  33  is conveniently positioned in handle  20  and comprises a fluid jet inlet  23  and a fluid jet outlet  28 , with fluid jet inlet  23  receiving a pressurized fluid source  21 , provided by a cylinder  21  received in handle  20 , as shown in FIG,  24 , or from a source external the instrument  10 , such as a pump or a pressurized fluid outlet common in an operating room environment and operatively connected to suture instrument  10 , as shown in  FIG. 25 .  
         [0049]     Fluid jet outlet  28  is positioned at an angle relative suture feed conduit  31  such that, upon release of the pressurized fluid source, a vacuum is induced at said suture feed inlet  23 . Once suture  50  leading end  51  is positioned relative fluid jet  33  depression of activation button  24 , permits the pressurized fluid to be delivered through fluid jet  33  and suture  50  is entrained with the pressurized fluid and passed through the instrument and the tissues to be joined. Delivery of leading end  51  to a point external a patient&#39;s body is provided by directing leading end  51  through a suture return path.  
         [0050]     Referring to  FIGS. 14-17 , a preferred suture  50  will have a surface irregularity  53  positioned proximal leading end  51 . Surface irregularity  53  is shaped to define a friction enhancing interface between the suture surface  54  and the pressurized fluid, facilitating entrainment of suture  50  with the pressurized fluid. As shown in  FIG. 14 , surface irregularity  53  is an abrasion or tuft on suture surface  54 . As shown in  FIG. 15 , surface irregularity  53  comprises a constriction  55  in the cross sectional surface area of suture  50 . Surface irregularity  53  may also be defined by a protrusion or bend  56  of suture material raised from the surface of the suture  50 , as shown in  FIG. 16 . Similarly, the constriction  55  of  FIG. 15  and the protrusion  56  of  FIG. 16  may be combined to define the compound surface irregularity  53  depicted in  FIG. 17 . Each embodiment is suitable for use on individual suture strands, i.e. each strand will produce an individual stitch.  
         [0051]     For continuous strands of suture material from which the surgeon may cut individual suture strands after retraction of instrument  10 , a plurality of surface irregularities  53  are provided spaced apart along the length of suture  50 . Each irregularity  53  is separated by a distance corresponding to a particular site of interest  11 . The separation distance will depend upon the size of the patient and the depth of the site of interest  11  and also will allow the leading end  51  and trailing end  52  to be accessible to the surgeon at a point external the patient&#39;s body.  
         [0052]     For continuous suture strands, the embodiments including a constriction  55  are particularly desirable. If a sufficient reduction in the cross sectional surface area is provided, constriction  55  will define a suture separator point, permitting the surgeon to readily sever an individual suture strand by pulling and snapping the trailing end  52  of the delivered preceding strand from the remaining length of suture material.  
         [0053]     In addition to manually inserting a single suture strand  50 , various methods are available for providing a suture  50  for use with suture instrument  10 . As shown in  FIG. 2 , a spool  70 , containing a strand of wound suture material  50  may be received in handle  20  such that leading end  51  may be positioned proximal fluid jet  33  for entrainment in the pressurized fluid stream. Alternately, as shown in  FIGS. 21-23 , suture  50  may be received in a cartridge  55  by winding, folding, or otherwise. Cartridge  55  may then be inserted into handle  20  such that suture leading end  51  is positioned proximal fluid jet  33  for entrainment in the pressurized fluid stream.  
         [0054]     As shown in  FIGS. 19A and 19B , spool  70  comprises, a spool winding surface  73  interposed between an inner spool face  72  and an outer spool face  74 . A bore  71  may be provided for rotation about a spindle in handle  20 . Handle  20  is adapted to receive spool  70  for axial rotation therein by any means known in the mechanical arts such as a spindle, bearing race or otherwise. To facilitate proper insertion of spool  70  into handle  20 , the diameter of inner spool face  72  may be sized smaller than the diameter of outer spool face  74 . Inner and outer faces  72 ,  74  may also have chamfered surfaces  78 , and  75  respectively, facing inwardly to winding surface  73  to facilitate winding of the spools with suture  50 . Moreover, the chamfered surface  75  on outer spool face  75  may also provide a bearing/seal interface between it and a corresponding race (not shown) provided in handle  20 . A spool end cap  76  may also extend from the outer face  74  to assist in providing a sealing interface. A knob  77  extends from end cap  76  to permit manual rotation of spool  70  for positioning suture leading end  51  proximal fluid jet  33 .  
         [0055]     In reference to  FIGS. 20 and 21 , cartridge  55  comprises a suture reservoir  56 , a coupler  57 , and a protective cap  58 . Preferably, coupler  61  is integrally formed with reservoir  63  to limit the presence of small loose articles in the operating room environment, thereby reducing the possibility of inadvertent introduction of foreign matter through an open incision. Reservoir  56  is a hollow member having an open end and a closed end and receives a length of suture  50  therein. A small bore  59  extending through the closed end may be provided to improve entrainment of suture  50 . Protective cap  58  is also a hollow member having at least one open end and attaches with coaxial alignments to suture reservoir  56  via coupler  57 . In its pre-insertion condition, protective cap  58  receives leading end  51  and a portion of suture  50  therein sufficient to position leading end  51  proximal fluid jet  33  upon insertion of cartridge  55  into the instrument. Protective cap  58  may be detachably coupled to reservoir  56 , however, to reduce the presence of loose articles in the operating room environment, protective cap  58  should be captively attached to suture reservoir  56 .  
         [0056]     As shown in FIGS.  20 B-C and  21 A-B, protective cap  58  is captively and slidably received within suture reservoir  56  such that as cartridge  55  is inserted into handle  20 , protective cap  58  retracts within reservoir  56 , thereby permitting insertion of leading end  51  proximal fluid jet  33 . In this configuration, an interference fit between coupler  57  and protective cap  58  maintains protective cap  58  in position during shipment and storage of cartridge  55 , while permitting protective cap  58  to retract during insertion of cartridge  55  into handle  20 . To ensure proper delivery and to prevent bunching or binding of suture  50  as protective cap  58  retracts into suture reservoir  56 , a portion of protective cap  58  should also extend into suture reservoir  56  and receive a forward portion of the wound or folded suture material  50 . In addition to joining protective cap  58  to suture reservoir  56 , coupler  57  also provides a coupling interface between cartridge  55  and a suture feed inlet  32  on the instrument handle  20 , as shown in  FIG. 23 .  
         [0057]     The coupling interface may be an interference fit, an index slot, or any similar arrangement. The protective cap may also be closed at one end opposite the open end joined to suture reservoir  56 . Preferably a pierceable membrane (#) closes this end to enhance the sterility of cartridge  55 . In this instance, suture feed inlet  32  may have a sharpened extension for piercing membrane ( ) as cartridge  55  is affixed to instrument  10 .  
         [0058]     As discussed previously, a cannula  12  may be employed to retract entry incision  13  and the tissues overlying the site of interest  11 . In this case, a simplified embodiment of suture instrument  10  is provided as depicted in  FIG. 13 . In this simplified suturing instrument  10 , hollow tissue penetrating needle  40  is hook shaped to reverse the suture delivery path. Tip  41  is positioned to direct leading end  51  back into the cavity  14  defined by cannula  12  for projection of suture leading end  51  to a point external the patient&#39;s body. The surgeon may then grasp leading end  51  and retract the instrument from the body. As the surgeon retracts the suture instrument, additional suture  50  material is drawn through the instrument. As discussed above, if suture  50  is an individual strand, the length of suture  50  should be such that its trailing end  52  will be drawn free of the instrument  10  once the instrument has been withdrawn from cannula  12 . The surgeon may then grasp trailing end  52 , then tie and manipulate knot  53  to a point adjacent the tissues to be joined  11 . If suture  50  is provided in a continuous strand, the surgeon may withdraw a length suture material from the instrument before severing the suture free of the instrument  10 .  
         [0059]     In the preferred embodiments of suturing instrument  10 , the suture return path is provided by the instrument itself. The suture return path is defined by a suture return conduit  36  having a receiving end  37 , selectively engageable with tip  41  of hollow tissue penetrating needle  40 , and a discharge end  38  proximal handle portion  20 . Suture  50 , entrained in the pressurized fluid is received by suture return conduit  36  at receiving end  37  and carried thereby to discharge end  38 . As suturing instrument  10  is retracted, suture  50  is draw from suture feed conduit  31  and suture return conduit  36  until leading end  51  and trailing end  52  are free of the instrument. The surgeon may then tie and manipulate knot  53  adjacent the site of interest  11 .  
         [0060]     In the embodiment depicted in  FIGS. 1-6 , elongated tubular member  30  comprises a selectively extensible sleeve  60 , operable by a lever  61 , extensibly coupled to handle portion  20  at a sleeve receiver  65 . Suture return conduit  36  and suture feed conduit  31  are received internal sleeve  60 . Sleeve  60  terminates at a flared portion  62  proximal tissue penetrating needle  40  and receiving end  37  of suture return conduit  36 . Actuation of lever  61  extends sleeve  60 , such that flared portion  61  urges receiving end  37  and needle  40  into cooperative engagement.  
         [0061]     In the embodiment depicted in  FIGS. 7 and 8 , an actuator lever  63  is pivotally connected to sleeve  60  and selectively urges receiving end  37  into cooperative engagement with a stationary needle  40 . An actuator rod  64  or cable operatively connects actuator lever  63  with lever  21  operative from handle portion  20 . By selecting a resilient material for suture return conduits, biasing means at leaver  21  may be eliminated. Preferably, actuator rod  64 , suture feed conduit  31  and suture return conduit  36  are received within sleeve  60 .  
         [0062]     In the embodiment depicted in  FIGS. 9 and 10 , a conventional scissors assembly may be utilized. In the embodiment depicted in  FIGS. 11 and 12 , hollow tissue penetrating needle  40  is hook shaped, with tip  41  directed towards handle portion  20 . Suture return conduit  36  is extensible relative handle  20  for cooperative engagement of receiving end  37  with needle  40 . In this instance trigger  27  may be operatively connected to suture return conduit  36 , permitting selective positioning of the conduit  36  relative needle  40 . Alternatively, a conventional scissors assembly may be employed without detracting from the utility of the invention.  
         [0063]     The specific embodiments and features discussed herein and shown in the accompanying drawings are exemplary of a suture instrument according to the present invention. As such many variations or modifications may be made without departing from the scope of the of the appended claims.