Abstract:
A surgical device having a latching mechanism comprising a latch member; and a retaining member having at least one aperture adapted to receive and retain said latch member in a locked position, said latch member and said retaining member being of contrasting colors so that when the latch member is locked in place by the retaining member that the latch member&#39;s presence in the locked position is externally visible.

Description:
FIELD OF THE INVENTION 
     The field of art to which this invention relates is surgical implements and more specifically, to the surgical devices with latching mechanisms, such as surgical staples and receivers, ligating clips and the like. 
     BACKGROUND OF THE INVENTION 
     Surgical devices of one and two part construction are quite well-known in the art. Examples of surgical devices such as surgical fasteners are described in U.S. Pat. Nos. 4,402,445, 4,506,670, 4,513,746, 4,534,352, 4,610,250, 4,667,674 and 4,932,960, all of which are incorporated herein by reference. Typically, these surgical devices contain two members formed from one or more absorbable materials. The device generally consists of at least one latching member i.e. a staple or fastener, and a retaining member. The latching member generally pierces the tissue in one or more locations and is locked into the retaining member. 
     In surgery, the surgical personnel who applies the surgical device using a mechanical applier often has no easy way to determine whether the latching member has locked into the retaining member. Currently, surgical personnel must manipulating the tissue to check for loose or unsecured staples, which is a time consuming procedure. Additionally, manipulating the tissue in this procedure leads to more tissue trauma and increases the risk of postoperative infections. What is needed, then, are surgical devices that permit surgical personnel to quickly determine whether a surgical device is secured. 
     Accordingly, it is an object of the present invention to provide a surgical device that permits surgical personnel to easily determine whether the surgical device is secured, thereby reducing the time required for surgical procedures. It is another object of the present invention to provide a surgical device that reduces the amount of tissue manipulation occurring during surgical procedures, thereby decreasing tissue trauma and the risk of postoperative infections. This and other objects and advantages will be apparent to those skilled in the art from the foregoing description of the present invention. 
     SUMMARY OF THE INVENTION 
     We have discovered a surgical device having a latching mechanism comprising a latching member; and a retaining member having at least one aperture adapted to receive and retain said latching member in a locked position; said latch member and retaining member being of contrasting colors so that when the latch member is locked in place by the retaining member that the latch member&#39;s presence in the locked position is visible. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective of the latch member and retaining member. 
     FIG. 2 is a cross-sectional view of the latch member and the retaining member of FIG.  1 . 
     FIG. 3 is a perspective view of a ligating clip. 
     FIG. 4 is a perspective view of the ligating clip of FIG. 3 secured to a vessel. 
     FIG. 5 is a perspective view of an apparatus for applying staples. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The inventive surgical latching device of polymeric material is shown in FIG. 1, FIG. 2, FIG.  3  and FIG.  4 . The latching device shown in FIG.  1  and FIG. 2 comprises a retaining member  104  and latching member  101 , which has a base  116  and at least two latches  102 . The latches  102  are substantially parallel and extend substantially perpendicularly from the same side of the base  116 . The latches  102  are generally attached to the base  116  adjacent to the ends of the base  116 . If more than two latches are placed on the base  116 , then the latches are spaced along the length of the base  116 . The latches  102  have barbs  105  which attach to shank  106 . The barbs  105  are tapered from the bottom  110  to the tip  108  of the barb  105  on at least on one side of the barb  105 . The bottom  110  of the barb  105  is wider than the shank  106 . The bottom  110  of the barb is joined to the shank  106 . An interlocking barb surface  112  is provided adjacent to the junction of the bottom  110  of the barb  105  and the shank  106 . 
     In surgical application the tissue to be joined is positioned between retaining member  104  and latching member  101 . The two latches  102  of latching member  101  are driven through tissue (not shown) into aperture  103  in the retaining member  104 . The latches  102  deflect as they pass through apertures  103 , but substantially return to their original orientation when the interlocking barb surface  112  overlaps and engages locking surface  114 . The engagement of the interlocking barb surface  112  of the latching member  101  and the locking surface  114  of retaining member  104  fastens the two members together with the tissue sandwiched in place between the two members  101  and  104 , in the locked position. 
     FIG.  3  and FIG.  4 . illustrate a ligating clip, which is a second embodiment of the present invention. The ligating clip  200  includes a latching member  212  and retaining member  214  connected at their proximal ends  212   a  and  214   a  by a resilient hinge section  216 . Provided at the distal ends  212   b  and  214   b  of the latching and retaining members  212  and  214  is a latching mechanism  218  for locking the members  212  and  214  in a closed position about body tissue, such as a vessel  220 , shown in FIG.  4 . In the illustrated embodiment, the latch mechanism is comprised of a latch  202  which is adapted to be lockingly received within a retainer  244  located in the distal end of  214   b  of the retaining member  214 . The latch  202  is comprises a barb  205  which is attached to shank  206 . The tip  208  is provided with a sharp edge  208   a  for penetrating any tissue (not shown) which might surround the vessel  220 . The barb  205  is flared from the tip  208  to the bottom  210 . The bottom of the barb  210  is wider that the shank  206 . The bottom  210  of the barb is joined to the shank  206 . An interlocking barb surface  211  is provided adjacent to the junction of the bottom  210  of the barb  205  and the shank  206 . The retainer  244  has an aperture  203  adapted to receive the latch  202  and a locking surface  234  adapted to engage interlocking barb surface  211  to maintained the ligating clip in the closed or locked position. Inspection port  230  at the distal end of retaining member  214  provides a means for visually inspect whether the latch  202  is locked into retainer  244 . 
     First and second lateral extensions  224   a  and  224   b  are integrally formed with the latching member  212 , and the third and fourth lateral extensions  224   c  and  224   d  extend outwardly from opposing wide walls of the retaining members  214  and are adapted to receive a clip closing force. The force applied to lateral extensions  224   a - 224   d  cause the distal ends  212   b  and  214   b  of the members  212  and  214  to move towards one another. The tip  208  of latching member  202  is driven through tissue (not shown) into aperture  203  in the retainer  244 . The latch  202  deflect as it passes through aperture  203  but substantially returns to its original orientation when the interlocking barb surface  211  overlaps and engages locking surface  234 . The engagement of the interlocking barb surface  211  of the latching member  202  and the locking surface  234  of retaining member  244  fastens the two members together with the tissue sandwiched in place between the two members  212  and  214 , in the locked position, with the vessel  220  engaged therebetween as shown in FIG.  4 . 
     To facilitate allowing surgical personnel to determine whether the surgical latching device in the locked position, a portion of the latch i.e. barbs ( 105 ,  205 ) as compared to a portion of the retainer i.e. locking surface ( 114 ,  234 ) and/or the apertures ( 103 ,  203 ) should be of contrasting colors. The entire latching member ( 101 ,  212 ) may also be of a contrasting color to enhance the visibility of the latching member being locked into retaining member ( 104 ,  214 ). As illustrated in FIG. 4 the inspection port  230  is provided to allow for visual inspection of the ligating clip to verify the clip is in the locked position. The inspection port may consist of an opening or a substantially transparent view port. 
     The contrasting colors preferably will show up easily against a film of blood, and most preferably one of the colors will appear dark and one color appears light. The contrasting colors can be created by using a colorant such as a dye or pigment. The colorant can be added to the polymeric material used to make the latching member or the retaining member. The colorant can also be added as an external coating. Suitable colorants are listed in the  Handbook of U.S. Colorants for Foods, Drugs, and Cosmetics,  second edition by Daniel M. Marmion which is hereby incorporated by reference. Colorants commonly used include D&amp;C Violet No.2, D&amp;C Green No.6, D&amp;C Green No.5, D&amp;C Blue No.6, [phthalocyaninato] (2-)] copper and black logwood dye. Additionally, when polymeric materials are used to form the surgical devices the contrasting colors can be created by leaving one component its natural color, “undyed” (i.e. white to golden color) and coloring the other component with an appropriate contrasting colorant. Currently preferred contrasting colors include but are not limited to contrasting colors selected from the group consisting of undyed/green, undyed/violet, undyed/blue, undyed/black, green/black, green/violet, green/blue and blue/black. 
     The surgical devices of the present invention can be made from biocompatable metals or polymeric materials which may or may not be bioabsorbable. Preferred absorbable polymers include poly(p-dioxanone), poly(glycolide), poly(lactide), poly(caprolactone), poly(hydroxybutyrate), poly(hydroxyvalerate), poly(anhydrides), copolymers thereof and blends thereof. Preferred non-absorbable polymers include nylon, polyester and polypropylene. The surgical devices may be molded or machined from these biocompatable materials. 
     The surgical devices of the present invention can be applied with many mechanical appliers such as the applier described in European Patent Application 93308924.5 (Publication No. 609612), which is hereby incorporated by reference herein. 
     “One apparatus for applying staples is shown in FIG.  5  and referred to generally by the reference number  10  consists of two main parts. These are actuator assembly  12  and fastener applying cartridge  14 . Actuator assembly  12  may be identical to the corresponding portion of the apparatus shown, co-pending Green U.S. patent application Ser. No. 267,080, filed May 26, 1981. Other actuator assemblies may be readily substituted for the actuator assembly shown. An example of another suitable actuator assembly is shown in co-pending Green U.S. patent application Ser. No. 188,691, filed Sep. 29, 1980. Thus, the particular actuator assembly in FIG. 5 illustrates only one possible environment of the invention and is not necessary to understanding or practicing the invention. 
     Actuator assembly  12  comprises a frame  20 , a clamp actuating mechanism pivoting element  22  and associated reciprocating element  24 , and pivoting pusher actuating member  26 . Fastener applying cartridge  14  is removably mounted in the distal portion of frame  20  by means of a detent or other similar connection between distal frame leg  28  and fastener retainer support member  30 . 
     Fastener applying cartridge  14  included longitudinal fastener retainer support member  30  and fastener holding assembly  40 . Fastener holding assembly  40  is pivotally connected to member  30  by pin  32  adjacent one end of a member  30 . Retainer support member  30  contains a plurality of fastener retainer members arranged in two parallel rows. Fastener holding assembly  40  similarly contains a plurality of fastener member arranged in two parallel rows. When fastener holding assembly  40  is pivoted substantially parallel to retainer support member  30 , each fastener member is opposite a respective one of retainer members. The fastener members and retainer members in each row are offset from the fastener members and retainer members in the other row to provide a staggered arrangement of finished fasteners in the fastened tissue.”