Patent Publication Number: US-2021186511-A1

Title: Surgical clip

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority to U.S. Provisional Application No. 62/950,819, filed on Dec. 19, 2019, the disclosure of which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to medical devices, and more particularly, to surgical clips for ligation of tissue. 
     BACKGROUND 
     Ligation of tissue (e.g., blood vessels, lymph nodes, nerves, cystic ducts, and cardiac tissue) is a common practice for many surgical procedures. This may be performed by closing the vessel with a surgical clip or by suturing the vessel with the surgical thread. The use of surgical thread requires complex manipulations of a needle and surgical thread to form knots required to secure the vessel. Such complex manipulations are time consuming and difficult to perform, particularly in endoscopic surgical procedures characterized by limited space and/or visibility. In contrast, surgical clips are relatively quick and easy to apply. Accordingly, the use of surgical clips in endoscopic and open surgical procedures has grown dramatically. 
     SUMMARY 
     The present inventors recognize that there is a need to improve one or more features of the surgical clips, such as the tissue-retaining capacity and/or torsional rigidity of the surgical clip. The disclosed devices and methods are directed to mitigating or overcoming one or more of the problems set forth above and/or other problems in the prior art. 
     One aspect of the present invention is directed to a surgical clip. The surgical clip may include a first leg member having a first inner surface with a curvature, the first leg member having a first thickness in a vertical direction, a first width in a lateral direction, and a first length in a longitudinal direction, where the first width is greater than the first thickness along at least half of the first length. The surgical clip may also include a second leg member having a second inner surface with a curvature, the second leg member having a plurality of teeth. 
     In some embodiments, the first width is greater than a second width of an inner portion of the first leg member. In some embodiments the first width is greater than a third width of an outer portion of the first leg member. In some embodiments, the first width is defined by at least one lateral protrusion extending from at least one side surface of the first leg member. In some embodiments, the at least one lateral protrusion extends at least half of the first length. In some embodiments, the at least one lateral protrusion extends at least two-thirds of the first length. In some embodiments, the at least one lateral protrusion does not extend the entire first length. In some embodiments, the surgical clip further includes at least one boss member on a distal portion of the first leg member, where a distal end of the at least one lateral protrusion is proximal of the at least one boss member. In some embodiments, the surgical clip further includes a hinge member pivotably joining the first leg member and the second leg member, where a proximal end of the at least one lateral protrusion is distal of the hinge member. In some embodiments, the at least one lateral protrusion includes a first lateral protrusion on a first side surface of the first leg member and a second lateral protrusion on a second side surface of the first leg member. In some embodiments, the plurality of teeth are disposed laterally of the second inner surface, the plurality of teeth being configured to extend past the first inner surface when the surgical clip is in a closed configuration. In some embodiments, the plurality of teeth extend from at least one side surface of the second leg member. In some embodiments, the plurality of teeth includes a first row of teeth and a second row of teeth, and the first row of teeth and the second row of teeth are configured to receive the first inner surface therebetween in a closed configuration. In some embodiments, the first row of teeth and the second row of teeth are staggered longitudinally, the first row of teeth are spaced apart longitudinally and the second row of teeth are spaced apart longitudinally. In some embodiments, the first inner surface and/or the second inner surface is substantially smooth. In some embodiments, the first inner surface has a concave curvature extending from a proximal portion to a distal portion of the first leg member, and the second inner surface has a convex curvature extending from a proximal portion to a distal portion of the second leg member. In some embodiments, the second leg member has a heel at a proximal portion of the second inner surface. In some embodiments, the surgical clip is a one-piece polymeric body. In some embodiments, the surgical clip further includes a hook member on a distal portion of the first leg member; and a tip member on a distal portion of the second leg member, where the hook member is configured to receive the tip member to retain the surgical clip in a closed configuration. 
     Another aspect of the invention is directed to a surgical clip formed of a one-piece polymeric body. The surgical clip may include a first leg member, a second leg member, and a hinge member. The first leg member may have a first inner surface with a concave curvature, a first outer surface, a first lateral protrusion extending from a first side surface, and a second lateral protrusion extending from a second side surface, the first leg member having a first thickness in a vertical direction defined between the first inner surface and the first outer surface, a first width in a lateral direction defined between the first lateral protrusion and the second lateral protrusion, and a first length in a longitudinal direction, where the first width is greater than the first thickness along at least half of the first length, the first width is greater than a second width of an inner portion of the first leg member, and the first width is greater than a third width of an outer portion of the first leg member. The second leg member may have a second inner surface with a convex curvature, the second leg member having a plurality of teeth disposed laterally of the second inner surface, and the plurality of teeth being configured to extend past the first inner surface when the surgical clip is in a closed configuration. The hinge member may pivotably join the first leg member and the second leg member, where a proximal end of each of the first lateral protrusion and the second lateral protrusion is distal of the hinge member. The surgical clip may include at least one boss member on a distal portion of the first leg member, where a distal end of each of the first lateral protrusion and the second lateral protrusion is proximal of the at least one boss member. The surgical clip may further include a hook member on a distal portion of the first leg member, and a tip member on a distal portion of the second leg member, where the hook member is configured to receive the tip member to retain the surgical clip in the closed configuration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the invention may be readily understood, aspects of this invention are illustrated by way of examples in the accompanying drawings. 
         FIG. 1  illustrates an exemplary perspective view of a first exemplary embodiment of a surgical clip in an open configuration according to the present invention. 
         FIG. 2  illustrates an exemplary frontal view of the surgical clip of  FIG. 1 . 
         FIG. 3  illustrates an exemplary side view of the surgical clip of  FIGS. 1 and 2 . 
         FIG. 4  illustrates an exemplary side view of the surgical clip of  FIGS. 1-3  in a closed configuration. 
         FIG. 5A  illustrates an exemplary cut-away view of a first leg member of the surgical clip of  FIGS. 1-4 . 
         FIG. 5B  illustrates an exemplary cross-section of the cut-away view of  FIG. 5A . 
         FIG. 5C  illustrates an exemplary cut-away view of a second leg member of the surgical clip of  FIGS. 1-5B . 
         FIG. 5D  illustrates an exemplary cross-section of the cutaway view of  FIG. 5C . 
         FIG. 6  illustrates an exemplary perspective view of a second exemplary embodiment of a surgical clip in an open configuration. 
         FIG. 7  illustrates an exemplary perspective view of a third exemplary embodiment of a surgical clip in an open configuration. 
         FIG. 8  illustrates an exemplary frontal view of the surgical clip of  FIG. 7 . 
         FIG. 9  illustrates an exemplary side view of the surgical clip of  FIGS. 7 and 8 . 
         FIG. 10A  illustrates an exemplary cutaway view of a first leg member of the surgical clip of  FIGS. 7-9 . 
         FIG. 10B  illustrates an exemplary cross-section of the cutaway view of  FIG. 10A . 
         FIG. 10C  illustrates an exemplary cutaway view of a second leg member of the surgical clip of  FIGS. 7-10B . 
         FIG. 10D  illustrates an exemplary cross-section of the cutaway view of  FIG. 10C . 
         FIGS. 11A-D  illustrate a first exemplary embodiment of a grooved hinge member of the surgical clip of  FIGS. 7-10D . 
         FIGS. 12A-D  illustrate a second exemplary embodiment of a grooved hinge member of the surgical clip of  FIGS. 7-10D . 
     
    
    
     DETAILED DESCRIPTION 
     The invention will now be described with reference to the figures, in which like reference numerals may refer to like parts throughout. The present invention is generally directed to a surgical clip configured to compress and/or ligate tissue (e.g., blood vessels, lymph nodes, nerves, cystic tubes, or cardiac tissue). The surgical clip may provide elongated leg members to increase the tissue-retaining capacity. For example, the surgical clip may be sized to fit in a 5 mm clip applier, but have an increased capacity compared to other 5 mm clips. To reinforce and stabilize at least one of the longer leg members, the surgical clip may have at least one lateral protrusion or wing member extending along at least one of the lateral sides of the leg member. The lateral protrusions may provide the leg member with an increased aspect ratio (width/thickness). Thus, the surgical clip is relatively wider along a portion of the thickness to increase the stiffness along at least a portion of the length of the leg member. The surgical clip may also have improved teeth that receive a tissue clamping inner surface therebetween for increased axial security of tissue. The surgical clip may further have features that retain tissue proximate the hinge as the surgical clip closes. The surgical clip may also have rounded leg and/or hinge profiles enhancing applier jaw strength and facilitating easier loading from a cartridge. In some embodiments, the surgical clip may have an improved hinge member. For example, the hinge member may be improved by removing material to form grooves in one or more side surfaces and/or an outer surface to reduce thickness. The grooves may improve the performance of the surgical clip during closure and/or provide features that could be used to help stabilize the surgical clip in the jaws of a clip applier, for example, if the clip applier had mating features. 
     In accordance with conventional practice, as used herein, and unless otherwise indicated herein, the term “longitudinal” is directed to the dimension which extends along the length of the surgical clip and/or leg members from their respective proximal portions to their respective distal portions, as would be commonly understood by one of skill in the art. Accordingly, the term “length” refers to a dimension of the surgical clip and/or one or more components along its longitudinal direction. Furthermore, the “transverse” direction is directed to any axis or direction which is orthogonal to the longitudinal lengths of the surgical clip or leg members. The term “vertical” refers to a dimension of the surgical clip and/or one or more components along a compression axis of the leg members. The term “thickness” refers to the dimension between opposing edges of the surgical clip and/or one or more components along the compression or vertical direction. The term “width” refers to a dimension of the surgical clip and/or one or more components in a lateral direction substantially transverse to the length and the thickness. The term “concave” and “convex” refers to the curvature of a surface or component visible when viewing an exterior of the surface or component. Similar terminology is used throughout the written disclosure, unless otherwise indicated. 
       FIGS. 1-5D  illustrate a first embodiment of a surgical clip  100  of the present invention. The surgical clip  100  may include a first leg member  102  having a proximal portion and a distal portion, and a second leg member  104  having a proximal portion and a distal portion. The first and second leg members  102 ,  104  may be integrally joined at the proximal portions by a hinge member  106 . 
     The first and second leg members  102 ,  104  may be curved along their lengths and include curved surfaces. For example, the first leg member  102  may include a first inner surface  108  and a first outer surface  110 , and the second leg member  104  may include a second inner surface  112  and a second outer surface  114 . The first inner surface  108  and second outer surface  110  may extend laterally between first side surfaces  116 , and the second inner surface  112  and second outer surface  114  may extend laterally between second side surfaces  118 . As shown in  FIG. 1 , the first inner surface  108  may have a concave curvature, and the first outer surface  110  may have a convex curvature, each along the length of the first leg member  102 . The second inner surface  112  may have a convex curvature, and the second outer surface  114  may have a concave curvature, each along the length of the second leg member  104 . The concave curvature of the first inner surface  108  and/or the convex curvature of the first outer surface  110  may extend from the respective proximal portion to the respective distal portion, substantially the entire length of the first leg member  102 . The convex curvature of the second inner surface  112  and/or the concave curvature of the second outer surface  114  may extend from the respective proximal portion to the respective distal portion, substantially the entire length of the second leg member  104 . The curvatures of the first leg member  102  and the second leg member  104  may substantially match, and the respective concavity/convexity of the first inner surface  108  and the second inner surface  112  may substantially match. The first and second leg member  102 ,  104  may bend and/or straighten as the surgical clip  100  closes, and the first and second inner surfaces  108 ,  112  may be approximated or contact in a closed configuration, as illustrated in  FIG. 4 . Further discussion of the general curvatures of the leg members  102 ,  104  and closure of the surgical clip  100  can be found in U.S. Pat. No. 4,834,096, the entire disclosure of which is incorporated herein by reference. 
     The hinge member  106  may be resiliently flexible and integral to the first and second leg members  102 ,  104 . The hinge member  106  may have a concave inner surface  120  joining the first inner surface  108  and the second inner surface  112  and a convex outer surface  122  joining the first outer surface  110  and the second outer surface  114 . The hinge member  106  may define an opening  123  through a thickness between the inner and outer surfaces  120 ,  122 , and the inner surface  120  may define a groove or slot  124  on its inside. The groove  124  may be configured to receive tissue extending between the leg members  102 ,  104 . 
     The surgical clip  100  may further have a convex portion or heel  126  on a proximal portion of the second leg member  104  at a distal end of the groove  124 . The heel  126  may have a convex curvature having a smaller radius of curvature than the remaining length of the second inner surface  112 , providing the heel  126  with increased convexity. The heel  126  may include at least one tooth  128  to increase securement of the tissue in the groove  124 . For example, the heel  126  may include a single tooth  128  extending substantially the width of the heel  126 . As further illustrated in  FIG. 4 , the heel  126  and/or at least one tooth  128  may be at least partially received in an opposing portion of the groove  124  in the closed configuration securing the tissue in the groove  124 . As illustrated in  FIG. 3 , the at least one tooth  128  may be angled proximally from the heel  126  toward the hinge member  106  to provide a counterforce to further prevent pull-off of the surgical clip  100 . 
     The surgical clip  100  may also include a latching mechanism having one or more latching elements. For example, the first leg member  102  may transition to a hook member  140  at its distal portion, and the second leg member  104  may transition to a complementary grooved tip member  142  at its distal portion. A distal portion of the hook member  140  may curve inwardly and point generally toward the hinge member  106 . The hook member  140  may have one or more transverse beveled surfaces and a concave inner surface which merges with the first inner surface  108  to define a latching recess. The tip member  142  may define a V-shaped groove or slot configured to receive the beveled surfaces of the hook member  140 , as the hook member  140  opens or deflects around the tip member  142  and/or the second leg member  104  compresses. The hook member  140  and the tip member  142  may engage to form the latching mechanism. For example, the latching recess may receive the tip member  142  in the course of compressing the surgical clip  100  into the closed configuration (e.g.,  FIG. 4 ) when secured position around a vessel or other tissue. 
     The leg members  102 ,  104  may include one or more boss members along the length to engage jaws of the clip applier. For example, the first leg member  102  may include one or more boss members  150  protruding perpendicular to opposing side surfaces adjacent to the distal portion of the first leg member  102  and immediately proximal of the hook member  140 . In the illustrated example of the surgical clip  100 , the one or more boss members  150  may be cylindrical and project outwardly beyond each of the side surfaces  116  of first leg member  102 . The boss members  150  may include a bridge section extending the width of the first leg member  102  and joining opposing boss members  150  extending laterally of the side surfaces  116 . The second leg member  104  may also include one or more boss members  152  at the distal portion spaced apart by the slot of the tip member  142 . The boss members  152  may be cylindrical and protrude perpendicularly to opposing side surfaces  118  of the second leg member  104 , extending longitudinally forward beyond the point of tip member  142  and outwardly beyond the side surfaces  118  of second leg member  104 . The jaws of the clip applier may engage the boss members  150 ,  152  and pivot the leg members  102 ,  104  about the hinge member  106  to compress the surgical clip  100  into the closed and/or latched configuration around a vessel. 
     As further shown in the embodiment of  FIGS. 1-5D , the surgical clip  100  may include a plurality of teeth  130 . The teeth  130  may be substantially rigid, such that the teeth  130  do not substantially deflect when engaging tissue. The teeth  130  may be positioned out-board relative to the surgical clip  100 . As used herein, the term “out-board” refers to the positioning of the teeth  130  laterally of the inner surface  112 . For example, the teeth  130  may be attached to and extend from at least one of the side surfaces  118  and/or substantially perpendicular to the second inner surface  112 . The teeth  130  may have a first portion  132  forming a base integrated into the second side surface  118 , and a second portion  134  protruding from the second leg member  104  toward the first leg member  102 . The first and second portions  132 ,  134  may be spaced apart from respective first and second portions  132 ,  134  of adjacent teeth  130 . The first portion  132  may be longitudinally wider than the second portion  134  to increase securement of the teeth  130  to the side surfaces  118 . The teeth  130  may have a substantially flat outer lateral side surface and a substantially flat inner side surface (defined by the exposed surface of the second portion  134  extending perpendicular from the inner surface  112 ), as illustrate in  FIGS. 5C and 5D . The substantially flat inner side surface of the second portions  134  may make a flush interface or minimal gap with the side surfaces  116  of the first leg member  102 . The second portion  134  may further have a substantially flat inner surface extending substantially parallel to the second inner surface  112  to reduce trauma on the ligated tissue. 
     The teeth  130  may form a first row of teeth  130  integrated into a first side surface  118  and a second row of teeth  130  integrated into a second side surface  118 . The teeth  130  may be positioned to clear the first inner surface  108  and extend along the side surfaces  116  of the first leg member  102  to enable the surgical clip  100  to close with minimal or no gap between the inner surfaces  108 ,  112  ensuring effective closure of small vessels. The first and second rows of teeth  130  may be configured to receive the first inner surface  108  therebetween in the closed configuration, as illustrated in  FIG. 4 . Thus, in the closed configuration, the teeth  130  may extend from the second side surfaces  118  past the first and second inner surfaces  108 ,  112 , and along or parallel to one of the first side surfaces  116 . Thus, in the closed configuration as illustrated in  FIG. 4 , the teeth  130  may overlap the first and second side surfaces  116 ,  118  and pass the first and second inner surfaces  108 ,  112 . The teeth  130  may be sufficiently spaced apart from each other along the longitudinal axis of the second leg member  104 , thus do not pinch tissue between adjacent teeth  130 . The teeth  130  of the first and second rows may be staggered, alternating along the longitudinal axis of the inner surface  112 . 
     The configuration of the teeth  130  may provide a favorable tortuous engagement of tissue with closely approximated tissue engaging surfaces. The larger size of the teeth  130  may improve tissue retention and prevent the tissue from slipping out of the surgical clip. The teeth  130  may further be easy to mold and not interfere with clip appliers. Thus, due to the out-board teeth of the second leg member  104  and the absence of teeth on the first leg member  102 , the first inner surface  108  and the second inner surface  112  may be substantially smooth (e.g., substantially without teeth) for substantially the entire length or majority of the length of the first and second leg members  102 ,  104 , with the exception for example of the tooth  128  on the heel  126 . For example, as illustrated, the first inner surface  108  may be completely without teeth, and the second inner surface  112  may be without teeth for the majority of its length. Further discussion of features of the out-board teeth  130  can be found in U.S. Patent Publication No. 2018/0368852, the entire disclosure of which is incorporated herein by reference. 
     The first leg member  102  may have at least one wing member or lateral protrusion  160  extending laterally from one of the first side surfaces  116 . For example, the at least one lateral protrusion  160  may include a first lateral protrusion  160  extending from a first side surface  116  and a second lateral protrusion  160  extending from a second side surface  116 . The lateral protrusions  160  may reinforce and stabilize the leg member  102  by increasing torsional stiffness. For example, the lateral protrusions  160  may enable the first leg member  102  to be longer without compromising the torsional and/or tissue retention strength of the surgical clip  100 . The lateral protrusions  160  may extend longitudinally for at least half of the length of the first leg member  102 . In some embodiments, the lateral protrusions  160  may extend longitudinally for at least two-thirds of the length of the first leg member  102 . However, the lateral protrusion  160  may not extend the entire length of the first leg member  102 . Thus, the lateral protrusions  160  may have a distal end that is proximal of the at least one boss member  150  to prevent interference with the clip applier interface and/or a proximal end that is distal of the hinge member  106  to maintain the flexibility of the hinge member, reducing the pivoting stiffness of the leg members  102 ,  104 . Furthermore, the width of the surgical clip  100  at the lateral protrusions  160  may be narrower than the width of the surgical clip  100  at the boss members  150 . As illustrated in the cutaway of the first leg member  102  in  FIG. 5A , the protrusion  160  may have an inner surface  164  spaced vertically from the first inner surface  108  and an outer surface  166  spaced vertically from the first outer surface  110 . The spacing of the inner surface  164  of the protrusion from the first inner surface  108  may prevent interference with tissue ligation and allow the teeth  130  to receive the inner surface  108  therebetween. The inner surface  164  may be substantially flat and extend substantially perpendicular from the side surface  116  to further reduce any interference with the teeth  130  and/or provide a surface for the teeth  130  to engage in the closed configuration. The outer surface  166  may be angled, tapered, and/or curved (concave or convex) to increase the stability of the protrusion  160  and facilitate manufacturing. As illustrated, the side surface of the protrusion  160  may be free and substantially flat. The spacing of the lateral protrusion  160  from the first inner surface  108  and first outer surface  110  may further optimize the reinforcement of the surgical clip  100 . 
     As further illustrated in the cut-away view of  FIG. 5A  and the cross-section of  FIG. 5B , the first leg member  102  may have a protrusion width (w1 P ) defined by side surfaces of opposing protrusions  160 . The protrusion width (w1 P ) may be greater than a first inner width (w1 1 ) defined by the dimension between the side surfaces  116  positioned between the protrusions  160  and the first inner surface  108 . The protrusion width (w1 P ) may also be greater than a first outer width (w1 O ) defined by the dimension between the side surfaces  116  and positioned between the protrusion  160  and to the first outer surface  110 . The protrusion width (w1 P ) may further be greater than a first thickness (t1) defined by the dimension between the first inner surface  108  and the first outer surface  110 . The protrusions  160  may extend for at least half of the length of the first leg member  102 , thus the protrusion width (w1 P ) may be greater than the first thickness (t1), first inner width (w1 I ), and/or the first outer width (w1 O ) for at least half of the length of the first leg member  102 . In embodiments where the protrusions  160  extend for at least two-thirds of the length of the first leg member  102 , the protrusion width (w1 P ) may be greater than the first thickness (t1), first inner width (w1 I ), and/or the first outer width (w1 O ) for at least two-third of the length of the first leg member  102 . The distal end of the at least one lateral protrusion  160  may define a distal surface that extends substantially perpendicular to the first side surface  116 , first inner surface  110  and/or the first outer surface  110 . The proximal end of the at least one lateral protrusion  160  may define a proximal surface that extends at an angle proximally relative to the first inner surface  110 . The first leg member  102  may have substantially flat side surfaces  116  distal and proximal of the lateral protrusions  160  (between the lateral protrusion  160  and the boss member  152  and/or between the lateral  162  and the hinge member  106 ). 
     Each of the lateral protrusions  160  may themselves have a width from the respective side surface  116  no greater than a quarter of the first inner width (w1 I ) and the first outer width (w1 O ). The lateral protrusions  160  may be only on the first leg member  102 , thus the second leg member  104  may be without a lateral protrusion. Thus, the protrusion width (w1 P ) of the first leg member  102  may be greater than a second width (w2) of the second leg member  104  defined by the dimension between the second side surfaces  118 , at cross-sections excluding and including the alternating, staggered teeth  130  (although the teeth  130  are not considered part of the side surfaces  118 ). The lateral protrusions  160  on the first leg member  102  may provide sufficient rigidity to the surgical clip  100  in the closed configuration, and the first leg member  102  having the hook member  140  may require additional rigidity and stability as the surgical clip  100  closes.  FIGS. 1-5D  illustrate a single lateral protrusion  160  extending from each side surface  116 , which facilitates manufacturing of the surgical clip  100 . However, it is also contemplated that the surgical clip  100  may include a plurality of lateral protrusions  160  on each side surface  116  (e.g. longitudinally aligned and/or spaced apart) collectively extending the lengths as described herein. 
       FIG. 6  illustrates a second embodiment of a surgical clip  100 ′ of the present invention. The surgical clip  100 ′ may include a first leg member  102 ′ having a proximal portion and a distal portion, and a second leg member  104 ′ having a proximal portion and a distal portion. The first and second leg members  102 ′,  104 ′ may be integrally joined at the proximal portions by a hinge member  106 ′. The surgical clip  100 ′ is a modification of the surgical clip  100 , thus substantially the entire discussion of  FIGS. 1-5D  applies to the surgical clip  100 ′ (except when otherwise indicated) and is expressly incorporated herein for brevity sake. 
     However, the surgical clip  100 ′ differs from the surgical clip  100  in that the surgical clip  100 ′ includes a plurality of teeth  136 ′ on the inner surface  108 ′ of the first leg member  102 ′. The plurality of teeth  136 ′ may form first and second staggered rows longitudinally along the first inner surface  108 ′. The plurality of teeth  136 ′ may be angled proximally toward the hinge member  106 ′. The combination of the teeth  136 ′ extending from the first inner surface  108 ′ and the out-board teeth  130 ′ extending from the second side surfaces  118 ′ may provide favorable retention strength based on the type and mechanical properties of the tissue. The second inner surface  112 ′ may be substantially smooth and engage the teeth  136 ′ of the first inner surface  108 ′. 
       FIGS. 7-10D  illustrate a third embodiment of a surgical clip  200  of the present invention. The surgical clip  200  may include a first leg member  202  having a proximal portion and a distal portion, and a second leg member  204  having a proximal portion and a distal portion. The first and second leg members  202 ,  204  may be integrally joined at the proximal portions by a hinge member  206 . 
     The first and second leg members  202 ,  204  may be curved along their lengths and include curved surfaces. For example, the first leg member  202  may include a first inner surface  208  and a first outer surface  210 , and the second leg member  204  may include a second inner surface  212  and a second outer surface  214 . The first inner surface  208  and second outer surface  210  may extend laterally between first side surfaces  216 , and the second inner surface  212  and second outer surface  214  may extend laterally between second side surfaces  218 . As shown in  FIG. 7 , the first inner surface  208  may have a concave curvature, and the first outer surface  210  may have a convex curvature, each along the length of the first leg member  202 . The second inner surface  212  may have a convex curvature, and the second outer surface  214  may have a concave curvature, each along the length of the second leg member  204 . The concave curvature of the first inner surface  208  and/or the convex curvature of the first outer surface  210  may extend from the respective proximal portion to the respective distal portion, substantially the entire length of the first leg member  202 . The convex curvature of the second inner surface  212  and/or the concave curvature of the second outer surface  214  may extend from the respective proximal portion to the respective distal portion, substantially the entire length of the second leg member  204 . The curvatures of the first leg member  202  and the second leg member  204  may substantially match, and the respective concavity/convexity of the first inner surface  208  and the second inner surface  212  may substantially match. The first and second leg member  202 ,  204  may bend and/or straighten as the surgical clip  200  closes, and the first and second inner surfaces  208 ,  212  may be approximated or contact in a closed configuration, (e.g., as similarly illustrated in  FIG. 4 ). Further discussion of the general curvatures of the leg members  202 ,  204  and closure of the surgical clip  200  can be found in U.S. Pat. No. 4,834,096, the entire disclosure of which is incorporated herein by reference. 
     The hinge member  206  may be resiliently flexible and integral to the first and second leg members  202 ,  204 . The hinge member  206  may have a concave inner surface  220  joining the first inner surface  208  and the second inner surface  212  and a convex outer surface  222  joining the first outer surface  210  and the second outer surface  214 . The hinge member  206  may define an opening  223  through a thickness between the inner and outer surfaces  220 ,  222 , and the inner surface  220  may define a groove or slot  224  on its inside. The groove  224  may be configured to receive tissue extending between the leg members  202 ,  204 . 
     The surgical clip  200  may further have a convex portion or heel  226  on a proximal portion of the second leg member  204  at a distal end of the groove  224 . The heel  226  may have a convex curvature having a smaller radius of curvature than the remaining length of the second inner surface  212 , providing the heel  226  with increased convexity. The heel  226  may include at least one tooth  228  to increase securement of the tissue in the groove  224 . For example, the heel  226  may include a single tooth  228  extending substantially the width of the heel  226 . The heel  226  and/or at least one tooth  228  may be at least partially received in an opposing portion of the groove  224  in the closed configuration securing the tissue in the groove  224  (e.g., as similarly illustrated in  FIG. 4 ). As illustrated in  FIG. 9 , the at least one tooth  228  may be angled proximally from the heel  226  toward the hinge member  206  to provide a counterforce to further prevent pull-off of the surgical clip  200 . 
     The surgical clip  200  may also include a latching mechanism having one or more latching elements. For example, the first leg member  202  may transition to a hook member  240  at its distal portion, and the second leg member  204  may transition to a complementary grooved tip member  242  at its distal portion. A distal portion of the hook member  240  may curve inwardly and point generally toward the hinge member  206 . The hook member  240  may have one or more transverse beveled surfaces and a concave inner surface which merges with the first inner surface  208  to define a latching recess. The tip member  242  may define a V-shaped groove or slot configured to receive the beveled surfaces of the hook member  240 , as the hook member  240  opens or deflects around the tip member  242  and/or the second leg member  204  compresses. The hook member  240  and the tip member  242  may engage to form the latching mechanism. For example, the latching recess may receive the tip member  242  in the course of compressing the surgical clip  200  into the closed configuration (e.g., as similarly illustrated in  FIG. 4 ) when secured position around a vessel or other tissue. 
     The leg members  202 ,  204  may include one or more boss members along the length to engage jaws of the clip applier. For example, the first leg member  202  may include one or more boss members  250  protruding perpendicular to opposing side surfaces adjacent to the distal portion of the first leg member  202  and immediately proximal of the hook member  240 . In the illustrated example of the surgical clip  200 , the one or more boss members  250  may be cylindrical and project outwardly beyond each of the side surfaces  216  of first leg member  202 . The boss members  250  may include a bridge section extending the width of the first leg member  202  and joining opposing boss members  250  extending laterally of the side surfaces  216 . The second leg member  204  may also include one or more boss members  252  at the distal portion spaced apart by the slot of the tip member  242 . The boss members  252  may be cylindrical and protrude perpendicularly to opposing side surfaces  218  of the second leg member  204 , extending longitudinally forward beyond the point of tip member  242  and outwardly beyond the side surfaces  218  of second leg member  204 . The jaws of the clip applier may engage the boss members  250 ,  252  and pivot the leg members  202 ,  204  about the hinge member  206  to compress the surgical clip  200  into the closed and/or latched configuration around a vessel. 
     As further shown in the embodiment of  FIGS. 7-10D , the surgical clip  200  may include a plurality of teeth  230 . The teeth  230  may be substantially rigid, such that the teeth  230  do not substantially deflect when engaging tissue. The teeth  230  may be positioned out-board relative to the surgical clip  200 . As used herein, the term “out-board” refers to the positioning of the teeth  230  laterally of the inner surface  212 . For example, the teeth  230  may extend inwardly from at least one wing member or lateral protrusion  262  extending perpendicularly from at least one of the side surfaces  218 . The teeth  230  may have a substantially flat outer lateral side surface and a substantially flat inner side surface (defined by the exposed surface extending perpendicular from the inner surface  212 ), as illustrate in  FIGS. 10C and 10D . The substantially flat inner side surface of the teeth  230  may make a flush interface or minimal gap with the side surfaces  216  of the first leg member  202 . The teeth  230  may further have a substantially flat inner surface extending substantially parallel to the second inner surface  212  to reduce trauma on the ligated tissue. 
     The teeth  230  may form a first row of teeth  230  extending from a first lateral protrusion  262  integrated into a first side surface  218  and a second row of teeth  230  extending from a second lateral protrusion  262  integrated into a second side surface  218 . The teeth  230  may be positioned to clear the first inner surface  208  and extend along the side surfaces  216  of the first leg member  202  to enable the surgical clip  200  to close with minimal or no gap between the inner surfaces  208 ,  212  ensuring effective closure of small vessels. The first and second rows of teeth  230  may be configured to receive the first inner surface  208  therebetween in the closed configuration (e.g., as similarly illustrated in  FIG. 4 ). Thus, in the closed configuration, the teeth  230  may extend from the lateral protrusions  262  past the first inner surfaces  208 , and along or parallel to one of the first side surfaces  216 . The teeth  230  may be sufficiently spaced apart from each other along the longitudinal axis of the second leg member  204 , thus do not pinch tissue between adjacent teeth  230 . The teeth  230  of the first and second rows may be staggered, alternating along the longitudinal axis of the inner surface  212 . 
     The configuration of the teeth  230  may provide a favorable tortuous engagement of tissue with closely approximated tissue engaging surfaces. The larger size of the teeth  230  may improve tissue retention and prevent the tissue from slipping out of the surgical clip. The teeth  230  may further be easy to mold and not interfere with clip appliers. Thus, due to the out-board teeth of the second leg member  204  and the absence of teeth on the first leg member  202 , the first inner surface  208  and the second inner surface  212  may be substantially smooth (e.g., substantially without teeth) for substantially the entire length or majority of the length of the first and second leg members  202 ,  204 , with the exception for example of the tooth  228  on the heel  226 . For example, as illustrated, the first inner surface  208  may be completely without teeth, and the second inner surface  212  may be without teeth for the majority of its length. Further discussion of features of the out-board teeth  230  can be found in U.S. Patent Publication No. 2018/0368852, the entire disclosure of which is incorporated herein by reference. 
     The first leg member  202  may have at least one wing member or lateral protrusion  260  extending laterally from one of the first side surfaces  216 . For example, the at least one lateral protrusion  260  may include a first lateral protrusion  260  extending from a first side surface  216  and a second lateral protrusion  260  extending from a second side surface  216 . The lateral protrusions  260  may reinforce and stabilize the leg member  202  by increasing torsional stiffness. For example, the lateral protrusions  260  may enable the first leg member  202  to be longer without compromising the torsional and/or tissue retention strength of the surgical clip  200 . The lateral protrusions  260  may extend longitudinally for at least half of the length of the first leg member  202 . In some embodiments, the lateral protrusions  260  may extend longitudinally for at least two-thirds of the length of the first leg member  202 . However, the lateral protrusion  260  may not extend the entire length of the first leg member  202 . Thus, the lateral protrusions  260  may have a distal end that is proximal of the at least one boss member  250  to prevent interference with the clip applier interface and/or a proximal end that is distal of the hinge member  206  to maintain the flexibility of the hinge member, reducing the pivoting stiffness of the leg members  202 ,  204 . Furthermore, the width of the surgical clip  200  at the lateral protrusions  260  may be narrower than the width of the surgical clip  200  at the boss members  250 . As illustrated in the cutaway of the first leg member  202  in  FIG. 10A , the protrusion  260  may have an inner surface  264  spaced vertically from the first inner surface  208  and an outer surface  266  spaced vertically from the first outer surface  210 . The spacing of the inner surface  264  of the protrusion from the first inner surface  208  may prevent interference with tissue ligation and allow the teeth  230  to receive the inner surface  208  therebetween. The inner surface  264  may be substantially flat and extend substantially perpendicular from the side surface  216  to further reduce any interference with the teeth  230  and/or provide a surface for the teeth  230  to engage in the closed configuration. The outer surface  266  may be angled, tapered, and/or curved (concave or convex) to increase the stability of the protrusion  260  and facilitate manufacturing. As illustrated, the side surface of the protrusion  260  may be free and substantially flat. The spacing of the lateral protrusion  260  from the first inner surface  208  and first outer surface  210  may further optimize the reinforcement of the surgical clip  200 . 
     As further illustrated in the cut-away view of  FIG. 10A  and the cross-section of  FIG. 10B , the first leg member  202  may have a protrusion width (w1 P ) defined by side surfaces of opposing protrusions  260 . The protrusion width (w1 P ) may be greater than a first inner width (w1 I ) defined by the dimension between the side surfaces  216  positioned between the protrusion  260  and the first inner surface  208 . The protrusion width (w1 P ) may also be greater than a first outer width (w1 O ) defined by the dimension between the side surfaces  216  and positioned between the protrusion  260  and to the first outer surface  210 . The protrusion width (w1 P ) may further be greater than a first thickness (t1) defined by the dimension between the first inner surface  208  and the first outer surface  210 . The protrusions  260  may extend for at least half of the length of the first leg member  202 , thus the protrusion width (w1 P ) may be greater than the first thickness (t1), first inner width (w1 I ), and/or the first outer width (w1 O ) for at least half of the length of the first leg member  202 . In embodiments where the protrusion  260  extends for at least two-thirds of the length of the first leg member  202 , the protrusion width (w1 P ) may be greater than the first thickness (t1), first inner width (w1 I ), and/or the first outer width (w1 O ) for at least two-third of the length of the first leg member  202 . The distal end of the at least one lateral protrusion  260  may define a distal surface that extends substantially perpendicular to the first inner surface  210  and the first outer surface  210 . The proximal end of the at least one lateral protrusion  260  may define a proximal surface that extends at an angle proximally relative to the first inner surface  210 . The first leg member  202  may have substantially flat side surfaces  216  distal and proximal of the lateral protrusions  260  (e.g., between the lateral protrusion  260  and the boss member  250  and/or between the lateral protrusion  260  and the hinge member  206 ). The outer surfaces  210 ,  214  of may have a rounded curvature extending between the respective side surfaces  216 ,  218  enhancing applier jaw strength and facilitating easier loading from a cartridge. The outer surface  222  of the hinge member  206  may have a similar rounded curvature. Each of the lateral protrusions  260  may themselves have a width from the respective side surface  216  no greater than a quarter of the first inner width (w1 I ) and the first outer width (w1 O ).  FIGS. 7-10D  illustrate a single lateral protrusion  160  extending from each side surface  116 , which facilitates manufacturing of the surgical clip  100 . However, it is also contemplated that the surgical clip  200  may include a plurality of lateral protrusions  260  on each side surface  216  (e.g. longitudinally aligned and/or spaced apart) collectively extending the lengths as described herein. 
     As further illustrated in the cut-away view of  FIG. 10C  and the cross-section of  FIG. 10D , the second leg member  204  may have a protrusion width (w2 P ) defined by side surfaces of opposing protrusions  262 . The protrusion width (w2 P ) may be greater than a width (w2) defined by the dimension between the side surfaces  218  and positioned between the protrusion  260  and to the second outer surface  214 . The protrusion width (w2 P ) may further be greater than a second thickness (t2) defined by the dimension between the second inner surface  212  and the second outer surface  214 . The protrusion  262  may extend for at least half of the length of the second leg member  204 , thus the protrusion width (w2 P ) may be greater than the second thickness (t2), and/or the second width (w2) for at least half of the length of the second leg member  204 . In embodiments where the protrusion  262  extends for at least two-thirds of the length of the second leg member  202 , the protrusion width (w2 P ) may be greater than the second thickness (t2), and/or the second width (w2) for at least two-third of the length of the first leg member  202 . The distal end of the at least one lateral protrusion  262  may defined a distal surface that extends substantially perpendicular to the first side surface  216 , the second inner surface  210 , and/or and the second outer surface  210 . The proximal end of the at least one lateral protrusion  262  may define a proximal surface that extends at an angle proximally relative to the second outer surface  214  and distally relative to the second inner surface  212 . The first leg member  202  may have substantially flat side surfaces  216  distal and/or proximal of the lateral protrusions  262  (e.g., between the lateral protrusion  262  and the boss member  252  and/or between the lateral protrusion  262  and the hinge member  206 ). 
       FIGS. 11A-D  illustrate a fourth embodiment of a surgical clip  200 ′ of the present invention. The surgical clip  200 ′ may include a first leg member  202 ′ having a proximal portion and a distal portion, and a second leg member  204 ′ having a proximal portion and a distal portion. The first and second leg members  202 ′,  204 ′ may be integrally joined at the proximal portions by a hinge member  206 ′. The surgical clip  200 ′ is a modification of the surgical clip  200 , thus substantially the entire discussion of  FIGS. 7-10D  applies to the surgical clip  200 ′ (except when otherwise indicated) and is expressly incorporated herein for brevity sake. The hinge member  206 ′ may further have one or more grooves  280 ′ in the outer surface  220 ′ extending between the opposing side surfaces  282 ′ of the hinge member  206 ′. For example, the hinge member  206 ′ may include three grooves, one at the apex of the outer surface  222 ′ and two on opposing sides of the apex. However, in some embodiments, the hinge member  206 ′ may have a single groove  280 ′, for example, at the apex of the outer surface  222 ′. The grooves  280 ′ may not extend completely through a thickness of the hinge member  206 ′ to the opening  223 ′, such that the grooves  280 ′ are not in communication with the opening  223 ′. The grooves  280 ′ may be substantially U-shaped and have curved or tapered side portions extending to the side surfaces  282 ′. The grooves  280 ′ may improve the performance of the surgical clip  200 ′ during closure and/or provide features that may be used to help stabilize the surgical clip  200 ′ in the jaws of a clip applier, for example, if the clip applier had mating features. 
       FIGS. 12A-D  illustrate a fifth embodiment of a surgical clip  200 ″ of the present invention. The surgical clip  200 ″ may include a first leg member  202 ″ having a proximal portion and a distal portion, and a second leg member  204 ″ having a proximal portion and a distal portion. The first and second leg members  202 ″,  204 ″ may be integrally joined at the proximal portions by a hinge member  206 ″. The surgical clip  200 ″ is a modification of the surgical clip  200 , thus substantially the entire discussion of  FIGS. 7-10D  applies to the surgical clip  200 ″ (except when otherwise indicated) and is expressly incorporated herein for brevity sake. The hinge member  206 ″ may further have one or more grooves  280 ″ in one or more of the side surfaces  282 ″. For example, the hinge member  206 ″ may include two grooves, one each in opposing side surfaces  282 ″. As illustrated in the exemplary embodiment, the grooves  280 ″ may extend from the outer surface  222 ″ through the side surfaces  282 ″ and into the opening  223 ″. The grooves  280 ″ may be substantially U-shaped and have curved or tapered side portions. The grooves  280 ″ may improve the performance of the surgical clip  200 ″ during closure and/or provide features that may be used to help stabilize the surgical clip  200 ″ in the jaws of a clip applier, for example, if the clip applier had mating features. 
     The various embodiments of the surgical clips of the present invention may be made of any suitable size and may be applied to any number of tissues, such as blood vessels, lymph nodes, nerves, cystic ducts, and cardiac tissue. The various embodiments of the surgical clips may be constructed from any suitable biocompatible material, such as metals and polymers. However, the present invention is particularly suitable for practice with polymeric clips. Thus, the various embodiments of the surgical clips  100 ,  100 ′,  200 ,  200 ′,  200 ″ preferably consist of a one-piece integral polymeric body formed from injection-molding, extrusion, or otherwise processed from a suitable strong biocompatible engineering plastic. Exemplary materials include homopolymer or co-polymer polyacetal, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyoxymethylene, or other thermoplastic materials.