Patent Publication Number: US-2022225978-A1

Title: Device for suture tensioning and methods thereof

Description:
REFERENCE TO RELATED APPLICATIONS 
     This international patent application claims priority to U.S. Provisional Patent Application No. 62/853,446 filed Jun. 10, 2019 and entitled “DEVICE FOR SUTURE TENSIONING AND METHODS THEREOF.” The 62/853,446 application is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The claimed invention relates to surgical devices, and more specifically to devices used in the management and tensioning of suture for minimally invasive surgical procedures. 
     BACKGROUND 
     Modern advances in minimally invasive cardiac surgery have enabled surgeons to perform surgical procedures which extend patient lives and improve patient quality of life while reducing post-operative pain, hospital stays, and post-operative limitations. Among such minimally invasive procedures, tricuspid valve repair is one of the more challenging procedures. In addition to the specialized medical knowledge and surgical skills needed to complete such a procedure, surgeons and their medical staff must also be very adept at suture management. It is desirable to have improved apparatuses which help surgical staff with suture management and maintaining appropriate suture tension. It would also be desirable to have improved apparatuses for suture management and tensioning which provide additional security and visual feedback to surgical staff during modern minimally invasive surgical procedures. 
     SUMMARY 
     A device for tensioning suture is disclosed. The device also includes a housing; a first cleat having a first gripping surface, the first cleat movably connected to the housing; a second cleat which is colinear with the first cleat and having a second gripping surface, the second cleat connected to the housing, where the second gripping surface is opposing the first gripping surface; an indicator biasing element connected to the housing and colinear with the first cleat and the second cleat; and an actuator connected to the housing and in contact with the first cleat. 
     The device for tensioning suture also includes a housing having a plurality of suture channels; a cleat array which may include: a first cleat array portion movably connected to the housing, the first cleat array portion may include a plurality of first cleats, each first cleat may include a first gripping surface, and a plurality of spacer blocks interposed between each first cleat; and a second cleat array portion fixedly connected to the housing, the second cleat array portion may include a plurality of second cleats, each second cleat may include a second gripping surface, where each second cleat is colinear with each first cleat, and a plurality of spacer blocks interposed between each second cleat. The device for tensioning suture also includes a plurality of indicator biasing elements, each indicator biasing element connected to the housing and colinear with the first cleat and the second cleat and each indicator biasing element may include a suture channel; and an actuator connected to the housing and in contact with the first cleat array portion where the actuator is movable between an unlocked position, a tensioned position, and a locked position. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1A  is a partial cross-sectional view of a suture tensioning device element of a suture tensioning device. 
         FIG. 1B  is a top-left-front perspective view of the suture tensioning device element of  FIG. 1A . 
         FIGS. 2A-2D  are partial cross-sectional views of a suture tensioning device during operation. 
         FIGS. 3A and 3B  are top-left-front and top-left-rear perspective views, respectively, of an embodiment of a suture tensioning device capable of tensioning six sutures. 
         FIG. 4  is a top-left-front perspective view of the suture tensioning device of  FIG. 3A  with the cover removed. 
         FIG. 5  is a top-left-front perspective view of a cleat array of the suture tensioning device of  FIGS. 3A and 3B . 
         FIGS. 6A-6C  are side views of different spacer elements of the cleat array of  FIG. 5 . 
         FIG. 7  is a top-left-rear perspective view of an embodiment of a crimping instrument, with the suture tensioning device of  FIG. 3A  loaded onto the shaft. 
         FIG. 8  is a top-left-rear perspective view of another embodiment of a crimping instrument, with the suture tensioning device of  FIG. 3A  loaded onto the shaft. 
     
    
    
     It will be appreciated that for purposes of clarity and where deemed appropriate, reference numerals have been repeated in the figures to indicate corresponding features, and that the various elements in the drawings have not necessarily been drawn to scale in order to better show the features. 
     DETAILED DESCRIPTION 
       FIG. 1A  is a partial cross-sectional view of a suture tensioning device element of a suture tensioning device. The suture tensioning device element of  FIG. 1A  is constructed of a first or top cleat  12  and a second or bottom cleat  22 . The top cleat  12  has two top cleat holes  14  configured to fasten or hole the top cleat  12  to an external structure or assembly, and a top cleat cam recess  16  configured to accept a cam (not shown here but will be discussed later in further detail). The suture facing gripping surface  12 A of the top cleat  12  also has several alternating surface recesses  18  and flat spots  20  configured to hold suture  10  with sufficient force when opposing or held in opposition to the bottom cleat  22 . The bottom cleat  22  has two bottom cleat holes  24  configured to fasten the bottom cleat  22  to an external structure or assembly. The suture facing gripping surface  22 A of the bottom cleat  22  also has several alternating protrusions or surface teeth  26 , flat spots  28 , and surface recesses  30 , configured to hold suture  10  with sufficient force when opposing or held in opposition to the top cleat  12 . The top cleat  12  and the bottom cleat  22  are colinear with one another and are arranged such that they lie within the same line or linear arrangement. The asymmetric teeth on the bottom cleat  22  are oriented in an opposing direction relative to the direction that the suture would be tensioned during operation of a suture tensioning device having a cleat pair such as the one depicted herein. The top cleat  12  or bottom cleat  22  may have alternate arrangements of protrusions, surface recesses  18  and flat spots  20 , such as alternate numbers of surface recesses  18  and flat spots  20 , surface recesses  18  and flat spots  20  arranged in a pattern other than alternating, or composed of similar features having various symmetrical or asymmetrical sizes and shapes, including, but not limited to saw tooth, square, rounded, ramped, triangular, or inversions or combinations thereof. The top cleat may or may not have all the aforementioned features, and the second cleat may or may not have all of the aforementioned features. Asymmetric teeth may be oriented in the same direction as tensioned suture, or in an opposing direction to the direction of the tensioned suture in alternate embodiments. The aforementioned shapes and features may be protruding or recessed from a plane line formed by the suture facing surface and may be composed of one or more than one of the aforementioned shapes or characteristics. The first cleat or top cleat  12  and the second cleat or bottom cleat  22  are constructed of plates that may be made of metal, plastic, or other rigid materials capable of holding sufficient holding force on a suture in such a configuration. It should be understood that the term “suture,” as used herein, is intended to cover any thread, cable, wire, filament, strand, line, yarn, gut, or similar structure, whether natural and/or synthetic, in monofilament, composite filament, or multifilament form (whether braided, woven, twisted, or otherwise held together), as well as equivalents, substitutions, combinations, and pluralities thereof for such materials and structures. 
     It should be noted that sufficient force refers to a minimum threshold level of force required to hold and tension suture between two opposing gripping surfaces configured in a locked position. Sufficient force may be dictated by a specific surgical procedural consideration, suture material property, or overall device configuration. Alternate suture materials or configurations may result in different actual values in terms of sufficient force required for holding and tensioning suture during minimally invasive surgical procedures. As an example, certain surgical procedures may require a holding force or tensioning force of at least 1 kg on a suture in order to pull one or more sutures simultaneously held in a tensioning device. The configuration or arrangement of a cleat pair may be modified in order to deliver this amount of holding force or tension.  FIG. 1B  is a top-left-front perspective view of the suture tensioning device element of  FIG. 1A . Similar to the view in  FIG. 1A , the suture  10  is shown held between the top cleat  12  and the bottom cleat  22 . 
       FIGS. 2A-2D  are partial cross-sectional views of a suture tensioning device during operation.  FIG. 2A  illustrates a suture tensioning device  32  having a tensioning device body  34 , several support walls  36 , each of the support walls  36  having a suture channel  38  configured to pass suture  10  therethrough and a side wall  40 . The suture tensioning device  32  also has a device cover  42  which may or may not be removable. The device cover  42  has an opening  44  configured to allow visualization of the top portion  50  of an indicator biasing element  48  by the user. The indicator biasing element  48  also has a beam  49 . The indicator biasing element  48  is connected to the device body  34  via an element support  46 . The indicator biasing element  48  also has a biasing element suture channel  52  passing therethrough, which is configured to receive suture. The location of the biasing element suture channel  52  on the indicator biasing element  48  is such that when suture  10  passing through the channel  52  is under tension, the beam  49  of the indicator biasing element  48  is configured to flex, and the top portion  50  is lowered relative to its position shown in  FIG. 2A . Thus, the indicator biasing element  48  is colinear with both the top cleat  12  and the bottom cleat  22 . The pair of the top cleat  12  and the bottom cleat  22  may also be referred to as a cleat pair. 
     The suture tensioning device  32  also has an actuator  54  coupled to an actuator mount  56 . A cam  58  is coupled to the actuator mount  56  which rotates when the actuator  54  is rotated. As the cam  58  is rotated through various positions, the cam  58  contacts the top cleat cam recess  16  of the top cleat  12 , moving the top cleat  12  into various vertical positions in relation to the bottom cleat  22 . Positioned between two support walls  36  is an alignment side plate  60  having two alignment side plate pin guides  62  attached to the top cleat  12  via two top cleat pins  64 . The two top cleat pins also attach a corresponding alignment side plate (not shown in this view) to an opposing side of the top cleat  12 . The top cleat  12  and its associated structure are movable within the device body  34  of the suture tensioning device  32 . The bottom cleat  22  is fixedly attached to the device body  34  via two bottom cleat pins  66 . The two bottom cleat pins  66  are passed through the alignment side plate pin guides  62  in the alignment side plate  60  for the purpose of vertically aligning the top cleat  12  and the bottom cleat  22  while the top cleat  12  is moved through its various positions. While the motion of the actuator brings the top cleat  12  closer to the bottom cleat  22 , the first cleat  12  and the second cleat  22  are not in contact and the suture passage through the various suture channels  38 ,  52  in the suture tensioning device  32  is not restricted when the actuator  54  is in the unlocked position shown in  FIG. 2A . 
       FIG. 2B  illustrates a partial cross-section of the suture tensioning device  32  with the actuator  54  moved into a partial tensioned position. When the actuator  54  is rotated in movement direction  68  the cam  58  also moves into a position where a different point on the radius of the cam  58  is in contact with the top cleat cam recess  16 . This position of the movement direction  68  coordinates with a partially locked position. In this partially locked position, the suture is only under a partial amount of the total force that can be delivered by the suture tensioning device  32 . In this position of the top cleat  12  relative to the bottom cleat  22 , the suture is held within the suture tensioning device  32  and can be moved through the device, with some resistance. In this partial locked or tensioned position, the suture  10  can travel through the various suture channels  38 ,  52  in the suture tensioning device  32 .  FIG. 2B  illustrates the suture tensioning device  32  in a partially locked position, where the first cleat  12  and the second cleat  22  are in partial contact and suture passage through the various suture channels  38 ,  52  in the suture tensioning device  32  is partially restricted. If the device  32  or suture  10  are moved relative to one another, there will be some drag or friction on the movement due to the partially tensioned state of the top cleat  12  relative to the bottom cleat  22 . 
       FIG. 2C  illustrates a partial cross-section of the suture tensioning device  32  with the actuator  54  moved into a fully locked position. When the actuator  54  is rotated in movement direction  72  the cam  58  also moves into a position where a different point on the radius of the cam  58  is in contact with the top cleat cam recess  16 . This position of the movement direction  72  coordinates with a fully locked position. In this fully locked position, the suture  10  is under the maximum amount of the total force that can be delivered by the suture tensioning device  32 .  FIG. 2C  illustrates the suture tensioning device  32  in a fully locked or locked position or configuration, such that the first cleat  12  and the second cleat  22  are in full contact and suture  10  passage through the various suture channels  38 ,  52  in the suture tensioning device  32  is fully restricted when the actuator  54  is in the locked position. 
       FIG. 2D  illustrates a partial cross-section of the suture tensioning device  32  with the actuator  54  in a fully locked position. Upon positioning and locking a suture  10  within the various suture channels  38 ,  52  in the suture tensioning device  32 , visual confirmation of appropriate suture tension may be desirable. It is also desirable in some minimally invasive surgical procedures to tighten suture once it has been secured in a suture tensioning device  32  such as the one shown and described herein. As the suture tensioning device  32  is pulled in a direction  76 , the suture is pulled taut, and is held firmly between the locked first cleat  12  and bottom cleat  22 . Since the suture  10  is threaded through the suture channel  38  and the indicator biasing element suture channel  52 , the suture  10  is moved from a loose configuration to a straight configuration when tightened, as shown in  FIG. 2D . The indicator biasing element  48  thus moves downward in direction  78 , moving the top portion  50  of the indicator biasing element  48  out of the opening  44  of the device cover  42 . This provides a visual indication to the operator that appropriate tension on the suture has been achieved within the suture tensioning device  32 . This visual effect is reversible and as tension on the device is relaxed, the indicator biasing element  48  will return to its original configuration and the top portion  50  of the indicator biasing element  48  returns to its original position in the opening  44  of the device cover  42 . The indicator biasing element  48  is designed and configured such that a threshold required level of tensioning force is on suture when locked. This amount of force needed for visual confirmation may be modified by utilizing alternate shapes materials or biasing element shapes. This may provide alternate levels of tensioning or visualization methods to indicate the appropriate tension on the suture has been achieved by locking the device. While the movement of the indicator biasing element  48  is shown as a means of tension visualization, other means known to those skilled in the art may also be used, such as color, letter, numeral, symbol, sound, or lighting effect. 
       FIGS. 3A and 3B  are top-left-front and top-left-rear perspective views, respectively, of an embodiment of a suture tensioning device capable of tensioning six sutures. A suture tensioning device  80  is illustrated having a body  82 , the body having two ergonomic gripping features  88 , an actuator  96  and a shaft recess  100 . The ergonomic gripping features  88  are configured such that they provide a comfortable hand position for holding and pulling multiple locked and tensioned sutures during a minimally invasive surgical procedure. The actuator  96  rotates a cam that engages in a cam recess in a top cleat such as those described in regard to  FIGS. 2A-2D . The shaft recess  100  is configured such that it and locks onto the shaft of a crimping instrument. Above the shaft recess  100  are several external suture channels  98  for the purpose of directing and organizing multiple sutures. The suture tensioning device  80  has a cover  90  with a cover opening  92  whereby six indicator tops  94  are visible therethrough. This embodiment of a suture tensioning device  80  has the capacity to lock, tension and provide visual indication related to six separate sutures used in a minimally invasive surgical procedure.  FIG. 3A  further illustrates the location of several top cleat pin locations  84 , not shown in this view, and bottom cleat pin locations  86 , showing the relative locations of the various cleat pairs within the suture tensioning device  80 . 
       FIG. 4  is a top-left-front perspective view of the suture tensioning device of  FIG. 3A  with the cover removed. The suture tensioning device  80  is shown with a suture  108  threaded through the device  80  and exiting through one of the suture channels  98 . With the cover removed, several top cleats  102  are visible, with multiple spacers  104  placed in between the top cleats  102 . The cam  106  attached to the actuator  96  is shown resting in a cam recess formed by the top cleats  102  and spacers  104 . These spacer blocks  104  are interposed between each of the top cleats  102 . 
       FIG. 5  is a top-left-front perspective view of a cleat array of the suture tensioning device of  FIGS. 3A and 3B . A cleat array  112  is shown in  FIG. 5 , which is constructed from several top cleats  102  and top cleat spacers  104 , interposed along the length of the top cleat array portion. The top cleat array portion is held together by two top cleat pins  114 . The individual components and the combined structure formed by the top cleats  102  and top cleat spacers  104  form an array cam recess  116  which receives a cam as described in previous embodiments herein. The cleat array  112  also contains several bottom cleats  118  interposed between several first bottom cleat spacers  120  and several second bottom cleat spacers  122 . The first bottom cleat spacer  120  has several relief recesses  124 , forming a bottom cleat array portion. The second bottom cleat spacers  122  also have several relief recesses  126  which are not shown in this view. The purpose of these relief recesses  124 ,  126  are to allow for suture to expand from out of the space between the top cleat  102  and the bottom cleat  118  when in the locked position. In some suture materials, in particular, suture made from expanded polytetrafluoroethylene (ePTFE), the suture may expand in an outward direction when under compression forces such as those created by the locking mechanism of the top and bottom cleats. Suture of such a design or material may break under tension if spatial allowance for expansion of suture under pressure is not made. These spacers or spacer blocks may have alternate arrangements, shapes or configurations of relief recesses known to those skilled in the art. The bottom array portion is held together by two bottom cleat pins  128 . The top portion and bottom portion of the array are held within a side alignment plate  130 . A corresponding side alignment plate  130  would be part of the cleat array  112 , but this one is not shown for purposes of visibility. The two alignment plates receive the top cleat pins  114  and bottom cleat pins  128  and align the top cleats  102  with the bottom cleats  118 . While this embodiment shows the cleat array being constructed of several pieces attached together to form the cleat array  112 , other embodiments may have a top portion or a bottom portion or both composed of a single piece while having some or all of the features and structure of the illustrated embodiment. These array pieces may be molded, printed, or machined out of a plastic material, or machined, printed, or cast of a metal or metal alloy material. Other materials or methods of constructing cleat arrays as described will be known to those skilled in the art. 
       FIGS. 6A-6C  are side views of different spacer elements of the cleat array of  FIG. 5 .  FIG. 6A  is a side view of a first bottom cleat spacer  120  demonstrating the location of the pin holes  132  and spacer recesses  124  defined by the first bottom cleat spacer  120 .  FIG. 6B  is a side view of a second bottom cleat spacer  122  demonstrating the location of the pin holes  134  and spacer recesses  126  defined by the second bottom cleat spacer  122 .  FIG. 6C  is a side view of a top cleat spacer  104  demonstrating the location of the pin holes  136  and cam recess  138  defined by the top cleat spacer  104 . 
       FIG. 7  is a top-left-rear perspective view of an embodiment of a crimping instrument, with the suture tensioning device of  FIG. 3A  loaded onto the shaft. An embodiment of a crimping instrument  140 , having three shafts  148 , a shaft support  150 , and three crimping ends  152 , can fasten three mechanical knots simultaneously. The crimping instrument  140  has a housing  142  defining a handle  144 . The instrument  140  has an actuation lever  146  which simultaneously crimps the mechanical fasteners and cuts sutures when actuated. The suture tensioning device  80  is placed onto the instrument over the shafts  148 . The suture tensioning device  80  is slidably engaged along the shafts  148  by placing the shaft recess  100  over the shafts  148  and can be pulled in a direction towards  153  the operator for the purpose of tensioning suture threaded through one or more mechanical fasteners. 
       FIG. 8  is a top-left-rear perspective view of another embodiment of a crimping instrument, with the suture tensioning device of  FIG. 3A  loaded onto the shaft. Another embodiment of a crimping instrument  154 , having three shafts  172 , a shaft support  174 , and three crimping ends  176 , can fasten three mechanical knots simultaneously. The crimping instrument  154  has a housing  156  defining a handle  158 . The instrument  154  has an actuation lever  160  which simultaneously crimps the mechanical fasteners and cuts suture when actuated. The suture tensioning device  80  is placed onto the instrument over the shafts  172 . The suture tensioning device  80  is slidably engaged along the shafts  172  by placing the shaft recess  100  over the shafts  172  and can be pulled in a direction towards  184  the operator for the purpose of tensioning suture threaded through one or more mechanical fasteners. On top of the housing  156  there is a guide rail  162  having a plurality of ratchets  164  on either side of the guide rail  162 . 
     The instrument  154  also has a snare assembly or snare loader  178  having a target tray  180  and a target cover  182 . A snare  170  within the snare loader  178  is threaded through the suture tensioning device  80  and anchored within the snare puller  166  (the anchoring mechanism is not shown in this view, but may be in the form of a mechanical fastener, handle, snare target or other structure suitable for anchoring a snare to the snare puller  166 . The snare puller  166  has ergonomic grips  168  for simultaneously pulling multiple snares in a direction  184  and through the suture tensioning device  80 . Similar embodiments such as this may have multiple snares loaded into the snare loader  178  for snaring multiple sutures and threading them through the suture tensioning device  80 . 
     In a minimally invasive surgical procedure requiring multiple sutures that need to be tensioned prior to a mechanical fastening step, the snare  170  pulls the suture through the suture tensioning device  80 . Once multiple sutures are threaded through and locked within the suture tensioning device  80 , the suture tensioning device  80  may be disengaged from the ends  176  and placed and engaged onto the guide rail  162 . If the suture tensioning device  80  needs further tensioning or adjustment in direction  184 , the ratchets  164  engage corresponding features in the suture tensioning device  80  to prevent reverse motion relative to direction  184 . Other means or methods of retaining the suture tensioning device  80  after tensioning and pulling may be known to those skilled in the art. 
     Various advantages of an apparatus for suture tensioning have been discussed above. Embodiments discussed herein have been described by way of example in this specification. It will be apparent to those skilled in the art that the foregoing detailed disclosure is intended to be presented by way of example only, and is not limiting. Various alterations, improvements, and modifications will occur and are intended to those skilled in the art, though not expressly stated herein. These alterations, improvements, and modifications are intended to be suggested hereby, and are within the spirit and the scope of the claimed invention. The drawings included herein are not necessarily drawn to scale. Additionally, the recited order of processing elements or sequences, or the use of numbers, letters, or other designations therefore, is not intended to limit the claims to any order, except as may be specified in the claims. Accordingly, the invention is limited only by the following claims and equivalents thereto.