BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates broadly to suturing devices for surgical applications. More particularly, this invention relates to devices that clamp and anchor suture material to tissue.  
         [0003]     2. State of the Art  
         [0004]     In surgical applications it frequently necessary to anchor tissue with suture material. Typically, the suture material is coupled to a needle and sewn into the tissue surrounding a surgical site (e.g., wound). The two ends of the suture material are tensioned and knotted to provide closure of the surgical site. The ability to control the tension on the suture material is important. To this end it is common for surgeons to tie double knots, that is a first knot to control tension and a second knot to secure the first knot. Such knot tying significantly extends the time required for suturing.  
         [0005]     There have been attempts to provide devices that take the place of conventional suturing with a suture needle and a length of suture material. Examples of devices that pinch or clamp the suture material are described in U.S. Pat. No. 2,075,508 to Davidson; U.S. Pat. No. 3,664,345 to Dabbs et al.; U.S. Pat. No. 3,976,079 to Samuels et al.; U.S. Pat. No. 4,291,698 to Fuchs et al.; U.S. Pat. No. 5,643,295 to Yoon; U.S. Pat. No. 5,720,747 to Burke; U.S. Pat. No. 5,810,853 to Yoon; U.S. Pat. No. 6,010,525 to Bonutti et al.; and U.S. Pat. No. 6,569,187 to Bonutti et al. These clamp-type devices are susceptible to inadvertent slippage of the suture material and loss of tension therein, and also have the disadvantage of requiring complex instruments, of being difficult to manipulate and/or not sufficiently reducing the time required for suturing and tying.  
         [0006]     Thus, there remains a need in the art for devices that facilitate more time efficient and effective suturing and tying.  
       SUMMARY OF THE INVENTION  
       [0007]     It is therefore an object of the invention to provide devices and methods for suturing tissue in a time efficient and effective manner.  
         [0008]     It is another object of the invention to provide devices and methods for suturing tissue that facilitate control over the tension applied to the suture material.  
         [0009]     It is a further object of the invention to provide suturing devices (and corresponding methods) that are easy to manipulate.  
         [0010]     In accord with these objects, which will be discussed in detail below, a suturing device for surgical applications includes first and second elements that are rotatable with respect to one another about a central axis. Each element has a cutout into its exterior surface. The cutouts, which extend along a direction substantially parallel to the central axis, are adapted to accept suture thread material therein. A central member is disposed along the central axis between the first and second elements to define space therebetween. When the first element is rotated with respect to the second element, the suture thread material is wrapped around the central member in the space between the first and second elements to thereby grasp and hold suture thread material. Preferably, the second element is realized with deformable material such that its cutout collapses and grasps suture material thread disposed therein.  
         [0011]     It will be appreciated that the two elements cooperate to efficiently and effectively grasp and hold suture thread material therein for a broad range of suturing applications, and facilitate tension control on the suture material thread.  
         [0012]     In the preferred embodiment of the invention, the device is made of bioabsorbable material for internal suturing procedures.  
         [0013]     Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1A  is an exploded view of a suturing device in accordance with the present invention;  
         [0015]      FIG. 1B  is a bottom view of the bottom element of the suturing device of  FIG. 1A ; and  
         [0016]      FIG. 2  is a schematic view of an alternate suturing device in accordance with the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]     Turning now to  FIGS. 1A and 1B , a suturing device in accordance with the present invention includes two elements  11 A,  11 B, preferably of annular shape as shown, that are rotatable with respect to one another about a central axis  12 . Such rotation is preferably accomplished by affixing a rotating member  13  to the element  11 B. The rotating member  13  rotates freely with respect to element  11 B about the central axis  12 , and snuggly fits into a bottom cavity  15  of element  11 A. The rotating member  13  includes a recess  17  that is accessible through a port  19  extending along the central axis of the element  11 A. The recess  17  is shaped to accept a drive tip  23  formed at the end of a mandrel  21 . The mandrel  21  is inserted thru the port  19  of element  11 A such that the surfaces of the drive tip  23  mate to the surfaces of the recess  17  of the rotating member  13 . Rotation of mandrel  21  causes the rotating member  13  (in addition to the element  11 A affixed thereto) to rotate with respect to element  11 B about the central axis  12 . In this manner, the two elements  11 A,  11 B are rotated with respect to one another.  
         [0018]     Preferably, such rotation is limited to one direction (e.g., either counter-clockwise or clockwise) by an annular ridged surface  25  disposed on the bottom side of the rotating member  13  as shown in  FIG. 1B . One or more pawls  27  are disposed on the top side  29  of the element  11 B. The ridged surface  25  and the pawls  27  cooperate such that the rotation of the two elements  11 A,  11 B with respect to one another is limited to one direction (e.g., either counter-clockwise or clockwise).  
         [0019]     The two elements  11 A,  11 B also have cutouts  31 A,  31 B into their exterior as shown in  FIG. 1A . The cutouts  31 A,  31 B extend along a direction substantially parallel to the central axis  12 . Preferably, the element  11 B is deformable upon crimping pressure applied thereto (which is preferably applied to one or more crimping grooves  33  disposed on the exterior surface of the element  11 B) such that the cutout  31 B collapses and grasps suture material thread disposed therein as described below.  
         [0020]     The suture material can be made of non-stretchable or stretchable, non-absorbable or absorbable materials. The suture material may also be coated with an antibiotic or other therapeutic drug. The suture material can have various outer-diameter or cross-sectional sizes in accordance with the surgical application.  
         [0021]     Preferably, the elements  11 A,  11 B have an annular shape with a diameter on the order of 0.125 inches and a height on the order of 0.1 inches. Moreover, the elements  11 A,  11 B and the rotating member  13  (and possibly the retention button described below) may be made of non-bioabsorbable material or bioabsorbable material (such as polymers or copolymers of lactide, glycolide, caprolactone, polydioxanone, trimethylene carbonate, polyorthoesters and polyethylene oxide). In addition, the elements  11 A,  11 B and the rotating member  13  (and possibly the retention button described below) may be coated with an antibiotic or other therapeutic drug. In this configuration, the suturing device  10  of  FIGS. 1A and 1B  can be used for suturing internal tissues and for microsurgical applications.  
         [0022]     During surgical operations, the elements  11 A,  11 B are initially positioned with respect to one another such that the cutout  31 A is substantially aligned with the cutout  31 B as shown. At least one suture material length is sewn into tissue in the vicinity of the surgical site. With the two elements  11 A,  11 B positioned at or near the sewn tissue, one or more segments of the suture material are positioned within the two cutouts  31 A and  31 B and subject to the desired amount of tension.  
         [0023]     While maintaining the desired amount of tension on the suture material, crimping pressure is applied to the element  11 B (preferably by applying pressure to the one or more crimping grooves  33 ) such that the element  11 B deforms and the cutout  31 B collapses and grasps the suture material thread disposed therein, thereby affixing the element  11 B to suture material thread at a position at (or near) the sewn tissue.  
         [0024]     The operator inserts the mandrel  21  through the port  19  such that the surfaces of the drive tip  23  mate to the surfaces of the recess  17 . The mandrel  21  is rotated such that top element  11 A rotates with respect to the bottom element  11 B. Such rotation causes the suture material passing through the cutout  31 A (and to the collapsed cutout  31 B) to wrap around the rotating member  13  in the annular space between the two elements  11 A,  11 B. The wrapping of the suture material around the rotating member  13 , which is preferably formed by one or more complete rotations of the top element  11 A with respect to the bottom element  11 B, effectively binds the suture material thereto. The one-way rotatability of the two elements  11 A,  11 B ensures that the suture material is held by the two elements with the desired amount of tension. In this manner, the suturing device of  FIGS. 1A and 1B  effectively grasps the suture material thread near tissue at a surgical site, and maintains the desired tension on the suture material thread.  
         [0025]     As described below with respect to  FIG. 2 , one end of the suture material may have a retention button permanently affixed thereto. The shape of the retention button can vary provided that it prevents the suture material from being pulled through the sewn tissue when tension is applied to the opposite end of the suture material. In this configuration, the suture material is sewn through the tissue at the surgical site with tension such that the retention button is disposed adjacent the sewn tissue. The other end of the suture material is then grasped and clamped with tension with the suturing device of  FIGS. 1A and 1B  to effectively maintain the desired tension on the suture material thread. Alternatively, the retention button may be omitted and replaced by a suture knot or other suitable suture retention mechanism.  
         [0026]     An alternate suturing device in accordance the present invention is shown in  FIG. 2 . The suturing device  10 ′ includes two elements  11 A′,  11 B′, preferably of annular shape as shown, that are rotatable with respect to one another about a central axis  12 ′. Such rotation is preferably accomplished by a central cylinder  51  that extends through a central annular opening in the top element  11 A′ and into a central annular opening in the bottom element  11 B′. The central annular opening in the bottom element  11 B′ is sized to enable the bottom element to rotate about the central cylinder  51 , while the central annular opening in the top element  11 A′ is sized such that the central cylinder  51  fits snuggly therein. The bottom element  11 B′ is held in place along the central axis  12 ′ by a snap ring or other suitable retention mechanism. The inside of the central cylinder  51  includes a recess portion  17 ′ that mates to the drive tip  23  of the mandrel  21  for rotating the central cylinder  51  (and the top element  11 A′ affixed thereto) with respect to the bottom element  11 B′, thereby rotating the top element  11 A′ with respect to the bottom element  11 B′. Preferably, rotational movement between the two elements  11 A′ and  11 B′ is limited to one direction (e.g., either counter-clockwise or clockwise) by an annular ridged surface (not shown) that is disposed on the bottom side of the element  11 A′ and cooperating pawls (not shown) that are disposed on the top side of the element  11 B′ in a manner similar that described above. The ridged surface and the pawls cooperate such that the rotation of the two elements  11 A′,  11 B′ with respect to one another is limited to one direction (e.g., either counter-clockwise or clockwise).  
         [0027]     The two elements  11 A′,  11 B′ also have cutouts  31 A′,  31 B′ into their exterior as shown in  FIG. 2 . The cutouts  31 A′,  31 B′ extend along a direction substantially parallel to the central axis  12 ′. Preferably, the element  11 B′ is deformable upon crimping pressure applied thereto (which is preferably applied to one or more crimping grooves (not shown) disposed on the exterior surface of the element  11 B′) such that the cutout  31 B′ collapses and grasps suture material thread disposed therein as described below.  
         [0028]     The suture material can be made of non-stretchable or stretchable, non-absorbable or absorbable materials. The suture material may also be coated with an antibiotic or other therapeutic drug. The suture material can have various outer-diameter or cross-sectional sizes in accordance with the surgical application.  
         [0029]     Preferably, the elements  11 A′,  11 B′ have an annular shape with a diameter on the order of 0.125 inches and a height on the order of 0.1 inches. Moreover, the elements  11 A′,  11 B′ and the cylinder  51  (and possibly the retention button  55  described below) may be made of non-bioabsorbable material or bioabsorbable material (such as polymers or copolymers of lactide, glycolide, caprolactone, polydioxanone, trimethylene carbonate, polyorthoesters and polyethylene oxide). In addition, the elements  11 A,  11 B and the rotating member  13  (and possibly the retention button  55  described below) may be coated with an antibiotic or other therapeutic drug. In this configuration, the suturing device  10 ′ of  FIG. 2  can be used for suturing internal tissues and for microsurgical applications.  
         [0030]     During surgical operations, at least one suture material length is sewn into tissue  53  in the vicinity of the surgical site. Preferably, one end of the suture material length(s) has a retention button  55  permanently affixed thereto. The shape of the retention button  55  can vary provided that it prevents the suture material from being pulled through the sewn tissue  53  when tension is applied to the opposite end of the suture material length. In this configuration, the suture material length is sewn through the tissue at the surgical site with tension such that the retention button is disposed adjacent the sewn tissue  53  as shown. Alternatively, the retention button  55  may be omitted and replaced by a suture knot or other suitable suture retention mechanism.  
         [0031]     The two elements  11 A′,  11 B′ are initially positioned with respect to one another such that the cutout  31 A′ is substantially aligned with the cutout  31 B′ as shown. With the two elements  11 A′,  11 B′ positioned at (or near) the sewn tissue  53 , one or more segments of the suture material (for example, one shown in  FIG. 2 ) are positioned within the two cutouts  31 A′ and  31 B′ and subject to the desired amount of tension.  
         [0032]     While maintaining the desired amount of tension on the suture material, crimping pressure is applied to the element  11 B′ (preferably by applying pressure to the one or more crimping grooves as described above) such that the element  11 B′ deforms and the cutout  31 B′ collapses and grasps the suture material thread disposed therein, thereby affixing the element  11 B′ to the suture material thread at a position near the sewn tissue  53 .  
         [0033]     The operator then inserts the mandrel  21  into the central cylinder  51  such that the surfaces of the drive tip  23  mate to the surfaces of the recess  17 ′. The mandrel  21  is rotated such that top element  11 A′ rotates with respect to the bottom element  11 B′. Such rotation causes the suture material passing through the cutout  31 A′ (and to the collapsed cutout  31 B′) to wrap around the central cylinder  51  in the annular space between the two elements  11 A′,  11 B′. The wrapping of the suture material around the central cylinder  51 , which is preferably formed by one or more complete rotations of the top element  11 A′ with respect to the bottom element  11 B′, effectively binds the suture material thereto. The one-way rotatability of the two elements  11 A′,  11 B′ ensures that the suture material is held by the two elements with the desired amount of tension. In this manner, the suturing device of  FIG. 2  effectively grasps the suture material thread near tissue at a surgical site, and maintains the desired tension on the suture material thread.  
         [0034]     There have been described and illustrated herein several embodiments of an improved suturing device and a suturing methodology utilizing such devices. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while particular configurations for guiding and grasping suture material thread and for effectuating rotation of a two suture guiding mechanisms have been disclosed, it will be appreciated that other configurations can be used as well. For example, the top element of the suturing device may also be deformable upon pressure applied thereto such that its cutout collapses and grasps suture material thread disposed therein and the two elements are fixed in position, thereby minimizing the risk of slippage of the suture material thread held therein. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed.
A suturing device for surgical applications includes first and second elements that are rotatable with respect to one another about a central axis. Each element has a cutout into its exterior surface. The cutouts extend along a direction substantially parallel to the central axis and are sized to accept suture thread material therein. A central member is disposed along the central axis between the first and second elements to define space therebetween. When the first element is rotated with respect to the second element, the suture thread material wraps around the central member in the space between the first and second elements to thereby grasp and hold suture thread material therein. Preferably, the second element is realized from deformable material such that its cutout collapses and grasps suture material thread disposed therein. In this manner, the two elements cooperate to efficiently and effectively grasp and hold suture thread material therein for a broad range of suturing applications, and facilitate tension control on the suture material thread.