REFERENCE TO PENDING PRIOR PATENT APPLICATION 
     This patent application claims benefit of pending prior U.S. Provisional Patent Application Ser. No. 60/816,407, filed Jun. 26, 2006 by Peter Marshall et al. for GRAFT LIGAMENT STRAND TENSIONER, which patent application is hereby incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to medical devices in general, and more particularly to devices for simultaneously positioning and tensioning, to a selected tension, a plurality of graft ligament strands. 
     BACKGROUND OF THE INVENTION 
     It is known in the art to use four graft ligament strands, such as two gracilis strands (e.g., a gracilis tendon doubled over) and two semitendinosus strands (e.g., a semitendinosus tendon doubled over), in the reconstruction of an anterior cruciate ligament (ACL). It is further known in the art to use other numbers of graft ligament strands, such as one, two or three strands, in an ACL reconstruction. It is also known in the art to use other anatomical materials, such as a patellar tendon, a quadriceps tendon, a tibialis tendon, etc., for an ACL reconstruction. 
     It is also known in the art to reconstruct other (i.e., non-ACL) ligaments using similar techniques. By way of example but not limitation, it is known in the art to reconstruct a posterior cruciate ligament (PCL) using similar techniques. 
     When using more than one graft ligament strand for a ligament reconstruction, it is generally preferred that the various ligament strands be equally tensioned, since this generally provides the best biomechanical results. The tension on each graft ligament strand may be applied by hand, one ligament at a time, but this approach is relatively time-consuming and makes it difficult to reliably tension each ligament strand to an equal, desired tension. Furthermore, this approach is generally impractical where the several graft ligament strands are to be secured to the host bone using a single fastener or anchor. 
     It is also possible to tension the graft ligament strands by hanging weights from each graft ligament strand. While this approach provides a known, equal tension on each graft ligament strand, it is generally fairly time-consuming to attach the weights to the various graft ligament strands. Furthermore, it can be awkward for the surgeon to work around the weights, which are hanging down from the free ends of the graft ligament strands, particularly at the point in the procedure when the surgeon is securing the graft ligament strands to the host bone (e.g., to the tibia, in the case of an ACL reconstruction). 
     Additionally, where a plurality of graft ligament strands are used in a graft ligament reconstruction and the plurality of graft ligament strands are being secured to the host bone using a single fastener or anchor, it is generally advantageous to be able to manipulate all of the graft ligament strands simultaneously, with an equal tension being applied to each graft ligament strand. However, applying tension equally to each of the several graft ligament strands can be complicated in situations where the graft ligament strands are positioned and tensioned using sutures extending from the strands, since the sutures are often not the same length. 
     Accordingly, there is a need for a new and improved graft ligament strand tensioner which may be used to simultaneously position and tension, to a desired tension, a plurality of graft ligament strands. 
     SUMMARY OF THE INVENTION 
     These and other objects of the present invention are addressed by the provision and use of the novel graft ligament strand tensioner which is hereinafter disclosed. 
     In one form of the invention, there is provided a graft ligament strand tensioner comprising: 
     a body; and 
     a pair of suture rails connected to the body, wherein each suture rail comprises a grooved outer channel for receiving a suture loop and a central mandrel for receiving a suture loop, wherein the separation of a suture loop received by the grooved outer channel is larger than the separation of a suture loop received by the central mandrel. 
     In another form of the present invention, there is provided a graft ligament strand tensioner comprising: 
     a body; and 
     a plurality of cleats connected to the body, wherein each of the cleats is configured to releasably secure a length of suture. 
     In another form of the present invention, there is provided a graft ligament strand tensioner comprising: 
     a body; 
     at least two suture-engaging elements for releasably engaging a pair of sutures, the at least two suture-engaging elements being connected to the body, in spaced-apart fashion, symmetrically about a center axis of the body; and 
     a handle pivotally connected to the body, such that the handle can be laterally positioned relative to the longitudinal axis of the body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which are to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein: 
         FIGS. 1-11  show a first preferred embodiment of the novel graft ligament strand tensioner of the present invention; 
         FIGS. 12-17  show a second preferred embodiment of the novel graft ligament strand tensioner of the present invention; 
         FIGS. 18-29  show various cleat assemblies which may be used with the novel graft ligament strand tensioner shown in  FIGS. 12-17 ; 
         FIGS. 30-32  show a third preferred embodiment of the novel graft ligament strand tensioner of the present invention; 
         FIGS. 33-36  show a fourth preferred embodiment of the novel graft ligament strand tensioner of the present invention; 
         FIG. 37  shows a fifth preferred embodiment of the novel graft ligament strand tensioner of the present invention; and 
         FIGS. 38-40  show a sixth preferred embodiment of the novel graft ligament strand tensioner of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Preferred Embodiment of the Novel Tensioner 
     Looking first at  FIGS. 1-11 , there is shown a first preferred embodiment of the novel graft ligament strand tensioner. More particularly, the novel graft ligament strand tensioner T generally comprises a handle body  1  ( FIG. 6 ), a handle beam  2 , a pair of slide rails  3  ( FIG. 11 ), a slide body  4 , a pair of compression springs  5  ( FIG. 11 ), a handle pivot pin  6 , a pair of suture rails  7 , a pair of handle grips  8 , a pair of retaining pins  9  ( FIG. 3 ), and a pair of retaining pin springs  10  ( FIG. 11 ), all of which are assembled together in the manner shown in the drawings, and as hereinafter discussed, so as to form the complete tensioner T. Tensioner T may be used to position and tension a plurality (e.g., four or two) graft ligament strands in the course of effecting a ligament (e.g., an ACL) reconstruction. By way of example but not limitation,  FIG. 1  shows tensioner T being used in a four-strand ligament reconstruction, and  FIG. 2  shows tensioner T being used in a two-strand ligament reconstruction. 
     More particularly, tensioner T comprises a slide body  4  ( FIG. 11 ) having two suture rails  7  attached thereto. Suture rails  7  are pinned to the sides of slide body  4  with retaining pin springs  10  and retaining pins  9 . Each suture rail  7  preferably has two suture guides, a grooved outer channel  7 A and a central mandrel  7 B ( FIGS. 7 ,  8  and  11 ). The grooved outer channels  7 A are preferably used as the suture guides during a four-strand graft reconstruction ( FIG. 1 ), and the central mandrels  7 B are preferably used as the suture guides during a two-strand graft reconstruction ( FIG. 2 ). 
     More particularly, during a four-strand graft reconstruction (e.g., an autograft procedure), it is generally desirable for the surgeon to keep each of the graft strands physically and visually separated from one another. The arched shape of the suture rails  7 , and hence the grooved outer channels  7 A, are designed so as to provide optimal vertical separation of the graft strands, and hence provide optimal visibility to the surgeon and optimal positioning of the graft strands, during reconstruction. During a two-strand graft reconstruction (e.g., an allograft procedure), there is no need to vertically separate two adjacent ligament strands, and any application of vertical separation forces to a single graft strand creates a risk that the single graft strand will tear during the procedure. This is due to the nature of the graft strand material itself and to any vertical separation forces applied to the single graft ligament strand. By looping the two sutures of a single graft ligament strand around the smaller central mandrel  7 B, rather than around the larger grooved outer channels  7 A, the risk of tearing the graft during a two-strand reconstruction procedure is significantly reduced. Thus, by providing two suture guide options (e.g., the larger outer groove channels  7 A and the smaller central mandrels  7 B), the surgeon is free to choose the suture position which will best suit the particular graft reconstruction being effected. 
     In addition to the foregoing, suture rails  7  are designed to work with sutures of different sizes and lengths. More specifically, the arched designs of outer groove channels  7 A and inner central mandrels  7 B permit the sutures to be tied in loops so as to eliminate the need for surgeons to precisely prepare each suture with identical lengths and positions in order to apply symmetric, simultaneous tension to the graft. 
     Suture rails  7  have inner hubs  7 C ( FIG. 11 ) with three lock grooves  7 D ( FIGS. 10 and 11 ). The lock grooves  7 D allow the suture rails  7  to lock in particular rotational orientations relative to slide body  4 , using locking fins  1 A ( FIGS. 10 and 11 ) of handle body  1 , thereby allowing for easier cleaning and storage of the assembled tensioner. 
     Handle body  1  is spring biased against slide body  4  ( FIG. 5 ). More particularly, handle body  1  is connected to slide body  4  by slide rails  3  ( FIG. 11 ) which (i) extend through bores  4 A formed within slide body  4 , (ii) extend through lumens  4 B formed in slide body  4 , and (iii) mount in handle body  1 . Compression springs  5  are captured between the enlarged heads  3 A of slide rails  3  and the annular shoulders formed at the interior bases of bores  4 A. Locking fins  1 A are located on the distal end of handle body  1  for selectively engaging lock grooves  7 D ( FIG. 10 ) on suture rails  7  as noted above. 
     Bores  4 A are partially open so that the surgeon may view both the compression springs  5  and slide rails  3  within the interior of slide body  4  ( FIG. 5 ). Markings ( FIGS. 5 and 6 ) alongside slide body  4  indicate the amount of tension applied to the graft ligament strands so as to provide the surgeon with a visual gauge of the tension being applied during the ligament reconstruction procedure. 
     Handle  8  ( FIG. 1 ) is connected to handle body  1  by a handle beam  2 . Handle beam  2  is in turn attached to handle body  1  by a handle pivot pin  6  ( FIG. 11 ). Furthermore, slide body  4  has a finger  4 C ( FIGS. 9 and 11 ) which projects proximally from slide body  4 , extending through an opening  1 B in handle body  1  and is selectively received in a locking groove  2 A ( FIG. 11 ) within handle beam  2 . In view of the foregoing construction, (i) when tensioner T is not under load, handle  8  is locked in position by virtue of finger  4 C seating in locking groove  2 A; and (ii) when tensioner T is under load, finger  4 C is no longer seated in locking groove  2 A ( FIG. 9 ) and handle  8  is free to rotate laterally about pivot pin  6 , whereby to minimize off-axis loading when tensioning the graft ligament strands. Handle  8  has a contoured grip ( FIG. 3 ) and is configured so as to enable one-handed use by the surgeon during the ligament reconstruction procedure. 
     The graft ligament tensioner T of the present invention will now be discussed in the context of its use in a four-strand ACL reconstruction ( FIG. 1 ), however, it should be appreciated that tensioner T may also be used in a two-strand reconstruction ( FIG. 2 ), as well as in other multiple-strand graft reconstructions. 
     In use, and looking now at  FIG. 1 , sutures S 1  and S 2 , extending from gracilis graft ligament strands G 1  and G 2 , are tied together at a knot KA at a selected distance from tibial tunnel opening TO. Then sutures S 1  and S 2  are looped around suture rail  7  in grooved outer channel  7 A. Similarly, sutures S 3  and S 4 , extending from semitendinosus graft ligament strands G 3  and G 4 , are tied together at knot KB and looped around the other suture rail  7  in grooved outer channel  7 A. Then the surgeon, holding tensioner T by handle  8 , pulls proximally away from the patient. As tensioner T is pulled back, handle body  1  is pulled away from slide body  4 , against the bias of compression springs  5 , and the graft ligaments are tensioned. As mentioned above, the degree of tension being applied to the graft ligaments strands can be measured by observing the degree of compression of springs  5  vis-à-vis the visual indicia ( FIGS. 5 and 6 ) marked on slide body  4 . This construction allows the surgeon to accurately determine when the selected degree of tension has been has been applied to the graft ligament strands during the reconstruction procedure. As handle body  1  is pulled away from slide body  4 , handle beam  2  moves away from finger  4 C formed on slide body  4  ( FIG. 9 ), freeing handle  8  for appropriate lateral positioning by the surgeon so as to equalize the tension on each of the ligament strands. Once the graft ligaments have been equally tensioned, the graft ligament strands are secured to the bone by any of the several fixation techniques well known to those skilled in the art. 
     In a reconstruction procedure where two ligament strands are to be used ( FIG. 2 ), the aforementioned procedure is preferably implemented with two sutures strands S 1  and S 2  looped around the two center mandrels  7 B ( FIG. 8 ), rather than the outer grooved channels  7 A of the suture rails  7 . 
     Second Preferred Embodiment of the Novel Tensioner 
     Looking now at  FIGS. 12-17 , in another preferred embodiment of the present invention, tensioner T may comprise a two-part slide body (i.e., a distal body  100  and a proximal body  105 , spring biased together as will hereinafter be discussed), with a set of suture cleat assemblies  110  attached to distal body  100 . Again, tensioner T may be used with four-strand ligament reconstructions, two-strand ligament reconstructions, etc. Each suture cleat assembly  110  attaches to lateral pivot fingers  115  located on distal body  100 . Each suture cleat assembly  110  has two cleats  120  on opposing ends of the cleat assembly. Suture cleat assemblies  110  can be locked into a vertical position when not under tension, i.e., by virtue of the engagement of proximal body fingers  125  with cleat assembly grooves  130  ( FIG. 13 ). 
     Distal body  100  is attached to proximal body  105  by rails  135  extending through bores  140  in distal body  100 . Compression springs  145  are captured on the rails within bores  140  of distal body  100 . More particularly, springs  145  are captured on rails  135  between the enlarged heads  147  of rails  135  and the bases of bores  140 . The proximal ends of the rails extend through openings in the distal body and are secured to proximal body  105 . Distal body  100  has windows  150  to provide the surgeon with a visual gauge of the degree of tension being applied to the graft ligament strands during use. 
     Proximal body  105  has a handle  155  attached to it so as to enable one-handed operation of tensioner T. 
     In use, suture strands (e.g., four or two strands) can be looped and/or wound around cleats  120  so as to secure the suture strands to the cleats. Preferably, one suture strand is attached to each cleat. Where tensioner T is used in a four-strand reconstruction, all four of the cleats  120  are used to secure separate suture strands; where tensioner T is used in a two-strand reconstruction, two of the cleats are used to secure separate suture strands and two of the cleats are let unused. After the suture strands are attached to the cleats, the surgeon pulls the handle proximally, away from the patient, so as to tension the graft ligament strands to the desired tension. The graft ligament strands can then be fixed in place by any of the several fixation techniques well known to those skilled in the art. 
     Significantly, inasmuch as cleat assemblies  110  are each independently mounted (e.g., via pivot fingers  115 ) to distal body  100 , the cleat assemblies  110  can rotate independently of one another. As a result, tensioner T can more easily balance the tension applied to each ligament strand. 
     Cleat Assemblies 
     It should be appreciated that the suture cleat assemblies  110  used with novel tensioner T shown in  FIGS. 12-17  may comprise any of a variety of different constructions and components. 
     Looking next at  FIGS. 18-21 , suture cleat assembly  110  may comprise an inner cleat  160  and an outer cleat  165 . Inner cleat  160  is seated within a recess  170 , mounted on a spring  175 , so that the inner cleat  160  is biased outboard of the cleat assembly body  180 . Inner cleat  160  and recess  170  have non-circular shapes in order to lock inner cleat  160  against rotation when inner cleat  160  is seated within recess  170 . Outer cleat  165  has a stem  185  which extends through inner cleat  160  and mounts to cleat assembly body  180 . When a suture strand is wound around stem  185 , spring  175  compresses and allows the suture strand to be captured between inner cleat  160  and outer cleat  165 . 
     In an alternate embodiment, and looking now at  FIGS. 22-25 , suture cleat assembly  110  may comprise an inner cleat  186  and an outer cleat  187 . Inner cleat  186  is mounted on an axle  188 , over a spring  189 , so that inner cleat  186  is biased outboard of the cleat assembly body  190 . Inner cleat  186  has a slot  191  which mates around the base  192  of cleat assembly body  190  to lock inner cleat  186  against rotation about axle  188 . Outer cleat  187  has a stem  193  which extends through inner cleat  186  and mounts on axle  188 . When a suture strand is wound around stem  193 , spring  189  compresses and allows the suture strand to be captured between inner cleat  186  and outer cleat  187 . 
       FIGS. 26-29  show another cleat assembly  110 . With this construction, a slide  194  on the cleat may be moved between an open position ( FIG. 27 ) and a closed position ( FIG. 28 ). More particularly, slide  194  is set in its open position ( FIG. 27 ) and suture is wound around the upper mandrel  195 , slide  194 , and the lower mandrel  196 . Then slide  194  is moved to its closed position ( FIG. 28 ) so as to capture the suture between the upper and lower mandrels  195 ,  196  and slide  194 . When the suture is to be released, slide  194  is moved back to its open position ( FIG. 27 ) and the suture withdrawn from the upper and lower mandrels  195 ,  196  and slide  194 . A button  197  is used to move slide  194  between its open and closed positions. 
     Third Preferred Embodiment of the Novel Tensioner 
     Looking next at  FIGS. 30-32 , another preferred embodiment of the present invention is shown. The novel tensioner T is generally similar to the tensioner T shown in  FIGS. 12-17 , except that with the construction shown in  FIGS. 30-32 , proximal body  105  has grooves  198  for capturing enlarged ends  147  of slide rails  135  as slide rails  135  extend from the bore within distal body  100 . As a result of this construction, proximal body  105  can be attached to distal body  100  during use, but proximal body  105  can be easily disconnected from distal body  100 , e.g., for cleaning and storage. 
     Fourth Preferred Embodiment of the Novel Tensioner 
     In another preferred embodiment of the present invention, and looking next at  FIGS. 33-36 , tensioner T may comprise a body  200  with internal rails  205 , springs  210  mounted on rails  205 , sliders  215  slidably mounted on rails  205 , and suture cleat assemblies  110  mounted to sliders  215 . More particularly, rails  205  are disposed within bores  220  in body  200 . Springs  210  and sliders  215  are mounted on rails  205 , with springs  210  biasing sliders  215  proximally (i.e., toward handle  225 ). Sliders  215  comprise fingers  230  which extend through openings  235  formed in the sidewalls of body  200 ; suture cleat assemblies  110  are mounted to fingers  230 , so that suture cleat assemblies  110  move with sliders  215 . Force view windows  236  are provided so as to provide the surgeon with visual feedback with respect to the amount of tension being applied. Handle  225  is secured to body  200  so as to enable one-handed operation of tensioner T. 
     In use, suture strands (e.g., four or two strands) are looped and/or wound around cleats  120 . After the suture strands are attached to cleats  120 , the surgeon pulls handle  225  proximally and the graft ligament strands are tensioned to the desired degree. The graft strands can then be fixed in place by any of the several fixation techniques well known to those skilled in the art. 
     Body  200  may include an anti-rotation boss  240 , and cleat assembly  110  may include an anti-rotation groove  245 , so that cleat assemblies  110  may be stabilized in the position shown in  FIG. 35  when tensioner T is not under tension. 
     Significantly, inasmuch as cleat assemblies  110  are each independently mounted (e.g., via sliders  215  and rails  205 ) to body  200 , the cleat assemblies  110  can move longitudinally independently of one another. As a result, tensioner T can more easily balance the tension applied to each ligament strand. 
     Fifth Preferred Embodiment of the Novel Tensioner 
     In another embodiment of the present invention, and looking next at  FIG. 37 , tensioner T may comprise a “unibody” design. In this construction, tensioner T has a handle  300  which is “rigidly” connected via a body  305  to two suture rails  7 , i.e., there is no spring assembly intervening between the handle and the two suture rails. Suture rails  7  preferably include grooved outer channels  7 A and central mandrels  7 B, whereby to facilitate a four-strand graft ligament reconstruction and a two-strand graft ligament reconstruction, respectively. Preferably, central mandrels  7 B are formed by providing a pair of slots  7 E in each of the grooved outer channels  7 A. 
     Sixth Preferred Embodiment of the Novel Tensioner 
     Another preferred construction is shown in  FIGS. 38-40 . More particularly, in  FIGS. 38-40  there is shown a tensioner T which is generally similar to the tensioner T shown in  FIGS. 33-36 , except that (i) the body  200  shown in  FIGS. 38-40  has a different geometry than the body  200  shown in  FIGS. 33-36 , and (ii) suture cleat assemblies  110  are replaced by suture rails  7 . 
     Modifications of the Preferred Embodiments 
     It should be understood that many additional changes in the details, operation, steps and arrangements of elements, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention.
A graft ligament strand tensioner is provided. The tensioner includes a body, a pair of suture rails connected to the body and a handle pivotally connected to the body. Each suture rail comprises a grooved outer channel for receiving a suture loop and a central mandrel for receiving a suture loop. The handle is pivotally connected to the body such that the handle can be pivoted relative to a longitudinal axis of the body only when the handle is under tension.