Abstract:
A fixation device includes a member defining at least two openings, and a suture tied to the member by passing the suture through the at least two openings in the member to form two suture loops through which ends of the suture pass. The two suture loops are interconnected. A method of securing a tissue graft includes providing the fixation member, attaching the suture to a tissue graft, and adjusting the length of the suture between the fixation member and the tissue graft by pulling.

Description:
BACKGROUND 
       [0001]    An anterior cruciate ligament (ACL) that has ruptured and is non-repairable is generally replaced arthroscopically by a tissue graft. The tissue graft can be harvested from a portion of a patellar tendon having so called “bone blocks” at each end, and from the semitendonosis and gracilis. Alternatively, the tissue graft can be formed from synthetic materials or from a combination of synthetic and natural materials. 
       SUMMARY 
       [0002]    To increase the graft/channel interface in femoral fixation for cruciate repair the distance between a graft fixation member and the tendon construct is reduced. The ability to minimize this distance is generally limited by fixation member flipping constraints, which results in less tendon in the femoral channel, or leads to making compromises in the size of the graft fixation member to accommodate the tendon and the flipping of the graft fixation member. 
         [0003]    According to one aspect, a method of securing a tissue graft includes providing a fixation member having a suture tied thereto by passing the suture through at least two openings in the fixation member to form two suture loops through which ends of the suture pass, attaching the suture to the tissue graft, and adjusting the length of the suture between the fixation member and the tissue graft by pulling the suture. 
         [0004]    Embodiments of this aspect may include one or more of the following features. 
         [0005]    The two suture loops are interconnected. Attaching the suture includes forming a loop of soft tissue of the tissue graft over the suture. Attaching the suture includes passing the suture through a bone block of the tissue graft followed by tying the suture to the fixation member. The method includes passing the fixation member, suture, and attached tissue graft through a bone passage, followed by adjusting the length of the suture between the fixation member and the tissue graft. 
         [0006]    According to another aspect, a fixation device includes a member defining at least two openings, and a suture tied to the member by passing the suture through the at least two openings in the member to form two suture loops through which ends of the suture pass. 
         [0007]    Embodiments of this aspect may include one or more of the following features. 
         [0008]    The two suture loops are interconnected. The member is elongated in a first dimension defining a length that extends between first and second ends of the member, and the member has a second dimension transverse to the first dimension that is smaller than the length. The member defines four, six, or seven holes. 
         [0009]    The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIGS. 1A and 1B  are illustrations of a tissue graft secured within the knee by a graft fixation member. 
           [0011]      FIG. 2  is another view of the knee joint of  FIG. 1 . 
           [0012]      FIGS. 3-6  are perspective views of embodiments of fixation devices. 
           [0013]      FIGS. 7A and 7B  are perspective views of an additional embodiment of a fixation device. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring to  FIGS. 1A and 1B , a knee joint has a tissue graft  10  (e.g., a patellar tendon graft ( FIG. 1A ) or a semitendonosis and gracilis graft ( FIG. 1B )) implanted in an anterior cruciate ligament (ACL) repair and reconstruction procedure. Prior to implanting tissue graft  10 , a notchplasty procedure is preferably performed to expand the intercondylar notch  12  of the femur bone. A femoral channel  14  for receiving one end of tissue graft  10  is then drilled from notch  12  a predetermined distance within the femur with a passing channel  16  of reduced diameter drilled further through the femur from femoral channel  14  to a region of femoral cortex  18 . A tibial channel  20  for receiving the other end of tissue graft  10  is drilled from an anterior region of the tibia to a region near the opening of femoral channel  14 . 
         [0015]    In the case of patellar tendon graft, one end of tissue graft  10  includes a bone block  22  which is shaped and sized in close conformity with femoral channel  14  to ensure optimal healing. A length of suture  24  has one end attached to bone block  22  and the other end secured at femoral cortex region  18  with a graft fixation member  26  of a fixation device  27 . The suture  24  is attached to the graft fixation member  26  in a manner that permits the length of the suture  24  between the graft fixation member  26  and the tissue graft  10  to be adjusted prior to or after the graft  10  and the fixation member  26  have been positioned as shown in  FIGS. 1A and 1B . The other end of tissue graft  10  includes a second length of suture  28  which is attached to the tibia, for example, with a fixation screw  30 . A washer  32  either attached to or positioned under the head of fixation screw  30  helps in holding the suture in place when screw  30  is tightened. 
         [0016]    The graft fixation member  26  is positioned using pull threads (not shown) attached to the member. The pull threads are passed through the channels  14  and  16  from the notch  12  to the cortex  18  and used to pull the graft fixation member  26  through the channels  14  and  16  with a long axis of the graft fixation member aligned with the channels. After exiting the channel  16 , the pull threads are used to flip the graft fixation member  26  so that the member  26  lies flat against the cortex. 
         [0017]    Referring to  FIG. 2 , length (L) of femoral channel  14  is selected by the surgeon in accordance with the length of bone block  22  and the desired insertion distance of tissue graft  10  within the femur. The span of suture  24 , designated as SS, is approximately that of passing channel  16  so that the sum of the desired insertion length (L) and span of suture (SS) is the measured total length (TL) from the opening of femoral channel  14  to the opening at femoral cortex  18 . Each of these dimensions is measured prior to implanting the tissue graft so that during the implantation procedure, the surgeon, under arthroscopic observation, can be assured that tissue graft  10  has been properly positioned within femoral channel  14 . 
         [0018]    The ability to adjust the length of the suture  24  allows the length of the suture span (SS) to be minimized, only being limited by the desired length of passing channel  16 . There is a minimum length of the suture  24  that is necessary during passage of the graft fixation member  26  through the channel  14 ,  16  to allow the member  26  to be positioned in alignment with the channels. Once the graft fixation member  26  is located against the femoral cortex  18 , the length of the suture  24  can be shortened by pulling on the suture to maximize the amount of the tissue graft  10  that is located within the femoral channel  14 . 
         [0019]    The suture  24  is a woven or braided suture, for example, #5 Ultrabraid suture, attached to the graft fixation member  26  in a loop and knot configuration to form a fixation device  40 . Referring to  FIG. 3 , the graft fixation member  26  is elongated in a first dimension defining a length, L, that extends between a first end  42  and a second end  44  of the member  26 , a second dimension transverse to the first dimension that has a width, W, smaller than the length, L, and a third dimension transverse to the first and second dimensions that has a height, H, small than the length, L. The graft fixation member has a bone contacting side  46  and an opposite side  48 . Extending between the sides  46 ,  48  are four holes  50 ,  52 ,  54  and  56 . The holes  50  and  56  receive the passing sutures, not shown. 
         [0020]    The suture  24  is a single length of suture passed through holes  52  and  54  to form two interconnecting loops  60 ,  62  through which ends  64 ,  66 , respectively, of the suture  24  are passed, created a knot  76  and a loop  68  of three suture loops  70 ,  72 , and  74 . To form the loop and knot configuration, for example, the end  66  of the suture  24  is passed down through hole  54  and up through hole  52 , creating loop  70 ; folded over on itself, around the length of suture extending up from hole  54 , and passed back down hole  52 , creating loop  60 ; passed up through hole  54 , creating loop  72 ; passed through loop  60 , folded over on itself, and passed back down hole  54 , creating loop  62  interconnected with loop  60 ; passed up through hole  52 , creating loop  74 ; and then passed through loop  62 . 
         [0021]    By pulling on the ends  64 ,  66  of the suture  24 , the length of the loop  68  can be adjusted, for example, from a minimum that equals the distance between the holes  52  and  54  to about 30 mm, such that, with the tissue graft  10  attached the suture  24 , the distance between the graft fixation member  26  and the tissue graft  10  can be adjusted between 0 mm and about 15 mm. 
         [0022]    When the fixation device  40  is used with a semitendonosis and gracilis graft ( FIG. 1B ), the suture  24  can be provided to the surgeon pre-tied to the graft fixation member  26 , and operating room personnel attach the tissue graft to the fixation device  40  by passing the tissue graft through the suture loop  68 . When a patellar tendon graft ( FIG. 1A ) is used, operating room personnel form the loop and knot configuration by passing the suture through the bone block of the graft while forming the loop and knot configuration. 
         [0023]    The distance between the graft fixation member  26  and the tissue graft  10  can be adjusted while the graft/fixation member construct is in the femoral tunnel. Alternatively, the distance is determined by the surgeon prior to placing the graft. 
         [0024]    Once the graft fixation member  26  and the tissue graft  10  are positioned in the knee with the desired length of the suture  24 , tension placed on the suture by the tissue graft acts to secure the loop and knot configuration. 
         [0025]    The length, width and height of the fixation member  26 , is for example, 12 mm.times.4 mm.times.1.5 mm. 
         [0026]    Other embodiments are within the scope of the following claims. 
         [0027]    For example, referring to  FIG. 4 , the suture loops  70 ,  72  and  73  can be twisted. Referring to  FIG. 5 , the suture loops  70  and  74  can be tightened against the bone contacting side  46  of the graft fixation member  26  such that in use the tissue graft is only attached to loop  72 . The graft fixation member  26   a  of  FIG. 6  includes six holes with the suture  24  being passed through four central holes to form loops  70 ,  72  and  74 , and knot  76 . The graft fixation member  26   b  of  FIGS. 7A and 7B  includes seven holes with the suture  24  being passed through five central holes  80 ,  82 ,  84 ,  86  and  88 . The form the suture construct, the suture end  66  is passed down through hole  88 , up through hole  86 , over the suture extending up from hole  88 , down through hole  84 , looped and passed back up through hole  84 , down through hole  82 , up through hole  80 , and through the loop formed between holes  84  and  82 . 
         [0028]    The graft fixation member can be modified to aid flipping of the member by providing open or closed ends, and variation in thickness, length or width. To aid in positioning the graft fixation member at the end of the channel, the member can have a banana shape or modifications such as rectangular, triangular or other geometric shapes. To aid in strength of pull out the thickness of the graft fixation member between the holes in the member can be adjusted. This section of the graft fixation member between the holes can be modified by increasing or reducing its thickness to open the space for and reduce the distance between the graft fixation member and the tissue graft. 
         [0029]    The graft fixation member can include only a single opening with the suture tied to graft fixation member by passing the suture through the single opening in the member to form two suture loops through which ends of the suture pass. 
         [0030]    Other implementations are within the scope of the following claims.