Patent Publication Number: US-9408690-B2

Title: Tissue repair assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of U.S. Ser. No. 12/631,960 filed Dec. 7, 2009, which is currently pending, which claims the benefit of U.S. Patent Application Ser. No. 61/120,898 filed on Dec. 9, 2008, the disclosures of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     1. Field of Technology 
     The present disclosure relates generally to soft tissue repair, and more specifically, devices and methods used for such repair. 
     2. Related Art 
     Current devices available for arthroscopic soft tissue repair include suture anchors, metal post and washer screws, and interference screws. These devices provide immediate fixation of the tissue to the bone with little postoperative activity modification. However, the tissue must be delivered out of the body, stitched, and then re-inserted into a previously drilled bone hole. This reinsertion can be done through a portal, but is very technically demanding, precluding some patients from being a candidate for this procedure. Additionally, these devices don&#39;t prevent the tissue from sliding past the device as the device is inserted into the bone hole and/or when repetitive loads are applied to the soft tissue after fixation. Slippage of the tissue past the device may lead to decreased or failed fixation of the tissue to the bone and therefore an unsuccessful repair. 
     Therefore, a procedure is needed that is simple, reproducible, and that would allow both beginner and experienced surgeons to perform the procedure. Similarly, the devices used in the procedure would be simple to use, cost effective, and marketable to arthroscopic and open surgery surgeons alike and configured to prevent the tissue from sliding past the devices. 
     SUMMARY 
     In one aspect, the present disclosure relates to a tissue repair assembly. The assembly includes an interference device and a fixation device coupled to the interference device, wherein the fixation device includes a coupling portion and a capturing portion. In an embodiment, the interference device includes threads on an outer surface of the interference device. In another embodiment, the capturing portion includes a semi-circular shape. In yet another embodiment, the capturing portion includes a first end having a hole and a second end having a hole. In a further embodiment, the interference device includes a cannulation. In yet a further embodiment, the capturing portion is a loop and includes a through hole. In an embodiment, the capturing portion includes a top surface, a bottom surface, and at least two grooves. In another embodiment, the capturing portion includes a through hole having a first opening on the top surface and a second opening on the bottom surface. In yet another embodiment, the capturing portion includes an opening and the interference device includes a tip, the tip extending through the opening. In a further embodiment, the first opening includes a rim surrounding the first opening. In yet a further embodiment, the capturing portion includes four grooves. 
     In an embodiment, the interference device is configured for engagement with soft tissue. In another embodiment, the fixation device is configured for engagement with soft tissue. In yet another embodiment, the fixation device is configured for engagement with the bone. In a further embodiment, the capturing device is open-ended. In yet a further embodiment, the capturing device is closed-ended. In an embodiment, the fixation device includes a shape memory material. In another embodiment, the coupling portion includes at least two legs. In yet another embodiment, each leg includes two ends, wherein one end is coupled to the capturing portion and the other end is coupled to the interference device. In a further embodiment, the coupling portion is coupled to the interference device via a snap-fit connection. 
     In another aspect, the present disclosure relates to a tissue repair assembly. The assembly includes an interference device and a fixation device coupled to the interference device, wherein the fixation device includes a proximal end and a pointed distal end. In an embodiment, the fixation device includes a channel extending a partial length of the fixation device. In another embodiment, the interference device includes a cannulation, wherein the fixation device is partially housed within the cannulation. In yet another embodiment, the fixation device is coupled to the interference device via engagement between surface features on the fixation device and surface features on the interference device. In a further embodiment, the fixation device includes a collar. In yet a further embodiment, the fixation device includes multiple pointed distal ends. 
     In yet another aspect, the present disclosure relates to a fixation device. The fixation device includes a base portion having a first leg, a second leg, and a groove located between the first and second legs; and a top portion extending from the base portion. In an embodiment, the device is cannulated. In another embodiment, both the first leg and the second leg include a pointed end portion. 
     In a further aspect, the present disclosure relates to a tissue repair assembly. In an embodiment, the assembly includes a fixation device having a base portion including a first leg, a second leg, and a groove located between the first and second legs, and a top portion extending from the base portion and an interference device coupled to the fixation device. In an embodiment, the fixation device is cannulated. In another embodiment, the interference device is cannulated. In yet another embodiment, the interference device is coupled to the top portion of the fixation device. In yet another embodiment, the interference device includes threads on an outer surface of the interference device. In a further embodiment, the interference device is configured for rotary advancement into a target tissue. 
     In yet a further aspect, the present disclosure relates to a method of tissue repair. The method includes preparing a hole in a bone; inserting soft tissue into the hole via the use of a fixation device; and inserting an interference device into the hole. 
     In an embodiment, the fixation device includes a base portion having a first leg, a second leg, and a groove located between the legs, and a top portion extending from the base portion. In another embodiment, the soft tissue is located within the groove of the fixation device when the soft tissue is advanced into the hole. In yet another embodiment, the method further includes applying tension to the soft tissue prior to inserting the interference device into the hole. In a further embodiment, inserting the interference device into the hole fixates the soft tissue to the bone. In yet a further embodiment, the interference device includes threads on an outer surface of the interference device. In an embodiment, the interference device is configured for rotary advancement into the hole. In another embodiment, insertion of the interference device into the hole occurs via rotary advancement of the interference device into the hole. 
     In yet another embodiment, the soft tissue includes a sleeve of woven or braided material. In a further embodiment, the fixation device engages the sleeve. In yet a further embodiment, the fixation device engages the sleeve and the soft tissue. In an embodiment, the fixation device engages the sleeve, the soft tissue, and the bone. In another embodiment, the fixation device engages the soft tissue and the bone. In yet another embodiment, the interference device includes a cannulation and the interference device is inserted into the hole such that the interference device is housed within the cannulation. In a further embodiment, the fixation device is coupled to the interference device via engagement between surface features on the fixation device and surface features on the interference device. In yet a further embodiment, the fixation device is coupled to the interference device via engagement between surface features on the fixation device and surface features on the interference device. In an embodiment, the sleeve is coupled to the soft tissue via use of a suture. 
     In an aspect, the present disclosure relates to a method of tissue repair. The method includes preparing a hole in a bone; inserting a soft tissue into the hole; inserting an interference device into the hole, the interference device including a cannulation; and inserting the fixation device into the hole such that the fixation device is housed within the cannulation. In an embodiment, upon insertion of the fixation device into the hole, the fixation device engages the soft tissue. In another embodiment, the fixation device engages both the soft tissue and the bone. 
     Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present disclosure and together with the written description serve to explain the principles, characteristics, and features of the disclosure. In the drawings: 
         FIG. 1  shows a perspective view of a first tissue repair assembly of the present disclosure. 
         FIG. 2  shows a perspective view of the tissue repair assembly of  FIG. 1  during soft tissue repair. 
         FIG. 3  shows a perspective view of a second tissue repair assembly of the present disclosure. 
         FIG. 4  shows a perspective view of the tissue repair assembly of  FIG. 3  during soft tissue repair. 
         FIG. 5  shows a perspective view a third tissue repair assembly of the present disclosure. 
         FIG. 6  shows a perspective view of the tissue repair assembly of  FIG. 5  during soft tissue repair. 
         FIG. 7  shows a cross-sectional view of a fourth tissue repair assembly of the present disclosure. 
         FIG. 8  shows a perspective view of the tissue repair assembly of  FIG. 7  during soft tissue repair. 
         FIG. 9A  shows a perspective view a fifth tissue repair assembly of the present disclosure. 
         FIG. 9B  shows a perspective view of the fixation device of the tissue repair assembly of  FIG. 9A . 
         FIG. 10  shows a perspective view of the tissue repair assembly of  9 A during soft tissue repair. 
         FIG. 11  shows a perspective view of the fourth tissue repair assembly during soft tissue repair wherein the soft tissue includes a sleeve. 
         FIG. 12  shows a perspective view of the fourth tissue repair assembly during soft tissue repair wherein the soft tissue strands include a sleeve. 
         FIG. 13A  shows a perspective view of a sixth tissue repair assembly of the present disclosure. 
         FIG. 13B  shows a perspective view of an alternative fixation device for use in the sixth tissue repair assembly of  FIG. 13A . 
         FIG. 14  shows a perspective view of a seventh tissue repair assembly of the present disclosure. 
         FIG. 15  shows a perspective view of an eighth tissue repair assembly of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses. 
       FIG. 1  shows a first tissue repair assembly  10  of the present disclosure. The assembly  10  includes an interference device  11  having a tapered body  11   a  and a cannulation  11   b . The body  11   a  includes a first portion  11   c  and a second portion  11   d  having threads  11   e.  The assembly  10  also includes a fixation device  12  coupled to the interference device  11 . The fixation device  12  includes a coupling portion  12   a  and a capturing portion  12   b . The coupling portion  12   a  includes a shaft  12   c  and a coupler  12   d . The coupler  12   d  includes an open-ended shape, such as a semi-circular shape, and is configured to provide a snap-fit connection to the body  11   a  of the interference device  11 . The capturing portion  12   b  also includes a semi-circular shape and has a first end  12   e  and a second end  12   f . The first end  12   e  includes a first opening  12   g  and the second end  12   f  includes a second opening  12   h . The first opening  12   g  is aligned with the cannulation and is configured to house a guide wire, as will be further discussed below, and the second opening  12   h  is configured to house a suture, as will be further described below. 
       FIG. 2  shows the assembly  10  disposed on a guide wire  13 . The guide wire  13  is advanced into a bone tunnel  21 , such as a tibial tunnel of a knee joint, and the assembly  10  is disposed on the guide wire  13 , such that the guide wire  13  is passed through the first opening  12   g  and the cannulation  11   b . A soft tissue graft  30  rests on the capturing portion  12   b  with each end  30   a , 30   b  of the graft  30  draped over the interference device  11 . A suture  14  may be used to further capture the graft  30  on the capturing portion  12   b  by placing ends of the suture  14  through openings  12   g , 12   h , such that the suture  14  is placed over the tissue  30 , and then tying the ends of the suture  14 . The assembly  10  and graft  30  are advanced into the bone tunnel  21 , via a delivery device (not shown). The threads  11   e  allow for compression of the graft  30  against the walls of the bone tunnel  21 . 
       FIG. 3  shows a second tissue repair assembly  40  of the present disclosure. The assembly  40  includes an interference device  41  having a tapered body  41   a  and a cannulation  41   b . The body  41   a  includes a first portion  41   c  and a second portion  41   d  having threads  41   e.  The assembly  40  also includes a fixation device  42  coupled to the interference device  41 . The fixation device  42  includes a coupling portion  42   a  and a capturing portion  42   b . The coupling portion  42   a  includes a shaft  42   c  and a coupler  42   d . The coupler  42   d  includes a semi-circular shape and is configured to provide a snap-fit connection to the body  41   a  of the interference device  41 . The capturing portion  42   b  is in a closed-ended shape, such as a loop, and includes a through hole  42   e  configured for disposal of a soft tissue graft. 
       FIG. 4  shows the assembly  40  located on a guide wire  50 . The guide wire  50  is advanced into a bone tunnel  61 , such as a tibial tunnel of a knee joint, and the assembly  40  is disposed on the guide wire  50 , such that the guide wire  50  is passed through the cannulation  41   b.  A soft tissue graft  70  is disposed through the hole  42   e  of the caturing portion  42   b  with each end  70   a , 70   b  of the graft  70  draped over the interference device  41 . The assembly  40  and graft  70  are advanced into the bone tunnel  61 , via a delivery device (not shown). The threads  41   e  allow for compression of the graft  70  against the walls of the bone tunnel  61 . 
       FIG. 5  shows a third tissue repair assembly  80  of the present disclosure. The assembly  80  includes an interference device  81  having a tapered body  81   a  having threads  81   e  and a cannulation  81   b . The assembly  80  also includes a fixation device  82  coupled to the interference device  81 . The fixation device  82  includes a coupling portion  82   a  and a capturing portion  82   b . The capturing portion  82   b  includes a top surface  82   e , a bottom surface  82   f , and a through hole  82   g . The through hole  82   g  includes a first opening  82   h  located on the top surface  82   e  and a second opening (not shown) located on the bottom surface  82   f . A rim  82   j  surrounds the first opening  82   h  and serves as the coupling portion  82   a  to couple the fixation device  82  to the interference device  81 . The rim  82   j  includes a diameter equal to an inner diameter of the interference device  81 . For the purposes of this disclosure, the capturing portion  82   b  includes four grooves  82   k   1 - 82   k   4 . However, the capturing portion  82   b  may have less than four grooves, such as the two grooves  82   k   1 , 82   k   3  for housing of end portions of a soft tissue graft, as will be further described below. In addition, it is also within the scope of this disclosure for the rim  82   j  to have a diameter less than or greater than an inner diameter of the interference device  81 . 
       FIG. 6  shows the assembly  80  located on a guide wire  90 . The guide wire  90  is advanced into a bone tunnel  101 , such as a tibial tunnel of a knee joint, and the assembly  80  is disposed on the guide wire  90 , such that the guide wire  90  is passed through the cannulation  81   b  and the through hole  82   g  of the capturing portion  82   b . A soft tissue graft  200  rests on the bottom surface  82   f  of the capturing portion  82   b  with each end  200   a , 200   b  of the graft  200  draped over the interference device  81  and housed in grooves  82   k   1 ,  82   k   3 . The assembly  80  and graft  200  are advanced into the bone tunnel  101 , via a delivery device (not shown). The threads  81   e  allow for compression of the graft  200  against the walls of the bone tunnel  101 . 
     For the purposes of  FIGS. 5 and 6 , it is within the scope of this disclosure for the capturing portion to not have grooves. Rather the sides of the capturing portion may be straight such that the portion is in the shape of a square. Other shapes are also within the scope of this disclosure. 
       FIG. 7  shows a fourth tissue repair assembly  300  of the present disclosure. The assembly  300  includes an interference device  301  having a tapered body  301   a  with threads  301   e  and a cannulation  301   b . The assembly  300  also includes a fixation device  302  disposed within the cannulation  301   b  of the interference device  301 . The fixation device  302  includes a proximal end  302   a , a pointed distal end  302   b , and a channel  302   c  extending a partial length of the fixation device  302 . 
       FIG. 8  shows the assembly  300  being advanced into a bone tunnel  401 , such as a tibial tunnel of a knee joint. A delivery device (not shown) is inserted into the channel  302   c  and the delivery device (not shown) is used to insert a soft tissue graft  500  into the bone tunnel  401 . The soft tissue graft  500  rests on the pointed distal end  302   b  with each end  500   a , 500   b  of the graft  500  draped over the interference device  301 . The assembly  300  and graft  500  are advanced into the bone tunnel  401 , via the delivery device (not shown) and the pointed distal end  302   b  extends through the graft  500  and into bone  402 . The threads  301   e  allow for compression of the graft  500  against the walls of the bone tunnel  401 . 
     Alternatively, the graft  500  is inserted into the tunnel  401 , the fixation device  302  is inserted into the tunnel  401  such that the pointed distal end  302   b  engages the graft, possibly being inserted through the graft  500  and into the bone  402 , and then the interference device  301  is inserted into the tunnel  401  such that the fixation device  302  is housed within the cannulation  301   b  and the ends  500   a , 500   b  of the graft  500  are draped over the device  301 . Insertion of the interference device  301  into the tunnel  401  directly after inserting the tissue  500  into the tunnel  401  and subsequently inserting the fixation device  302  into the cannulation  301   b  such that the pointed end  302   b  is inserted through the graft  500  and possibly into the bone  402 , is also within the scope of the disclosure. The fixation device  302  may be of a variety of lengths and may include surface features that mate with surface features located within the cannulation  301   b  to further couple the fixation device  302  to the interference device  301 . The surface features may include threads, barbs, ribs, or other surface features known to one of skill in the art and that have the ability to further facilitate coupling between the fixation device  302  and the interference device  301 . It is also within the scope of this disclosure for the fixation device  302  and/or the interference device  301  to be made out of a material, such as a shape memory material, that expands or otherwise allows for further coupling between the devices  301 , 302  in response to body temperature or an external energy source. 
       FIG. 9A  shows a fifth tissue repair assembly  600  of the present disclosure. The assembly  600  includes an interference device  601  having a tapered body  601   a  with threads  601   e  and a cannulation  601   b . The assembly  600  also includes a fixation device  602  disposed within the cannulation  601   b  of the interference device  601 . As shown in  FIG. 9B , the fixation device  602  includes a first leg  602   a , a second leg  602   b , and a groove  602   c  located between the legs  602   a , 602   b . The device  602  also includes a top portion  604  extending from the base portion  603 . As can be seen in  FIG. 9A , the top portion  604  has a smaller diameter than the cannulation  601   b  so as to allow the top portion  604  to be disposed within the cannulation  601   b . In addition, the device  602  is cannulated to allow passage of a guide wire  610  through both the interference device  601  and the fixation device  602 . As will be further described below, the legs  602   a , 602   b  and the groove  602   c  cooperate to house soft tissue within the groove and fixate the tissue within a bone tunnel. For the purposes of  FIGS. 9A and 9B , the fixation device  902  is U-shaped. However, the device may be V-shaped or have any other shape known to one of skill in the art. 
       FIG. 10  shows the assembly  600  located on the guide wire  610 . The guide wire  610  is advanced into a bone tunnel  701 , such as a tibial tunnel of a knee joint, and the assembly  600  is disposed on the guide wire  610 , such that the guide wire  610  is passed through both the interference device  601  and the fixation device  602 . A soft tissue graft  800  rests between the legs  602   a , 602   b  with each end  800   a , 800   b  of the graft  800  draped over the interference device  601 . The assembly  600  and graft  800  are advanced into the bone tunnel  701  together, via a delivery device (not shown). The threads  601   e  allow for compression of the graft  800  against the walls of the bone tunnel  701 . Alternatively, the assembly  600  may be advanced into the tunnel  701  such that the fixation device  602  is advanced into the tunnel  701  followed by advancement of the interference device  601 . In this manner, tension may be applied to the soft tissue  800  prior to inserting the interference device  601  into the tunnel  701 . 
       FIGS. 11 and 12  show tissue repair assemblies  900  that are similar to the fourth tissue repair assembly  300  and method shown in  FIGS. 7 and 8 , albeit including a sleeve of braided or woven material  1100  on the tissue  1000 . As shown in  FIGS. 11 and 12 , one strand or multiple strands of tissue  1000  may be fixated within the tunnel  1200 . While the sleeve  1100  is located between the ends  1000   a , 1000   b , it is within the scope of this disclosure for the sleeve  1100  to be located anywhere along the length(s) of the strand(s)  1000  or over the entire strand(s)  1000  prior to placing the tissue(s)  1000  within the bone tunnel  1200 . Having the sleeve  1100  on the tissue(s), such as in  FIGS. 11 and 12 , allows for maintaining the soft tissue(s)  1000  at the tapered end  902  of the interference device  901  via insertion of the fixation device  903  through at least a portion of the sleeve  1100 , thereby alleviating the need for the fixation device  903  to be inserted through the soft tissue  1000 . However, as shown in  FIGS. 11 and 12 , it is also within the scope of this disclosure for the fixation device  903  to be inserted through the soft tissue  1000  and the sleeve  1100  or the soft tissue  1000 , the sleeve  1100 , and the bone  1201 . Additionally, rather than using one sleeve  1100  for all of the strands of tissue  1000 , as shown in  FIG. 12 , it is also within the scope of this disclosure to have a sleeve  1100  located on each strand of tissue  1000 . A flexible member, such as a suture, may be used to couple the sleeve  1100  to the tissue  1000 . 
       FIG. 13A  shows a sixth tissue repair assembly  1300  of the present disclosure that is similar to the fourth tissue repair assembly  300  of  FIG. 7 . However, assembly  1300  includes a collar  1303  located on the fixation device  1302 . When the assembly  1300  is used to fixate soft tissue to bone via a method similar to the method of  FIG. 8 , the collar  1303  further facilitates maintenance of the location of the soft tissue in front of, or at the tapered end of the interference device  1301 . 
       FIG. 13B  shows an alternative fixation device  1302  for use with repair assembly  1300 . Rather than having one pointed distal end  1302   b , the device may have multiple pointed distal ends  1302   b . This would allow the device  1300  to capture more of the tissue and therefore provide for increased fixation of the tissue to bone. For the purposes of  FIG. 13B , the device  1300  includes only two pointed distal ends  1302   b . However, it is within the scope of this disclosure for the device  1300  to include more than two pointed distal ends  1302   b.    
       FIG. 14  shows a seventh tissue repair assembly  1400  of the present disclosure that is similar to the tissue repair assembly  10  of  FIG. 1 . However, instead of shaft  12   c , the fixation device  1600  includes a coupling portion  1600   a  having at least two legs  1600   b . Each leg  1600   b  has one end  1600   c  coupled to the capturing portion  1600   d  and another end  1600   e  coupled to a thread  1501  of the interference device  1500 . For the purposes of this disclosure, each end  1600   e  includes a foot  1600   f  that allows for snap lock coupling of the foot  1600   f  to the thread  1501  and therefore coupling of the fixation device  1600  to the interference device  1500 . The legs  1600   b  are tapered to accommodate the tapered end portion  1502  of the device  1500 . It is within the scope of this disclosure for the legs  1600   b  to be of different lengths such that one foot  1600   f  is coupled to one thread  1501  and the other foot  1600   f  is coupled to a different thread  1501 . It is also within the scope of this disclosure for the coupling portion  1600   a  to have more than two legs  1600   b . The capturing portion  1600   d  is of a semi-circular shape so as to capture soft tissue in a manner similar to how the capturing portion  12   b  of the assembly  10  of  FIGS. 1 and 2  capture tissue. However, the capturing portion  1600   d  may be of any other shape that would allow capturing of the tissue and maintenance of it in front of or at the tapered end  1502  of the interference device  1500  during and after repair. The ends  1600   c , 1600   e  may be coupled to the capturing portion  1600   d  and the interference device  1500  in any manner known to one of skill in the art. 
       FIG. 15  shows an eighth tissue repair assembly  1700  of the present disclosure. The assembly  1700  is similar to assembly  80  of  FIG. 5 . However, the interference device  1701  of assembly  1700  includes a tip  1703  that extends beyond the tapered end  1702  of the device  1701 . The fixation device  1704  is coupled to the interference device  1701  such that the tip  1703  extends through a center opening  1705  of the device  1704 . During repair, soft tissue is disposed on the fixation device  1704  in a manner similar to how soft tissue is disposed on the fixation device  82  of assembly  80  and shown in  FIG. 6 . 
     The assemblies  10 ,  40 ,  80 ,  300 ,  600 ,  900 ,  1300 ,  1400 ,  1700  of the present disclosure, and especially the fixation devices  12 ,  42 ,  82 ,  302 ,  602 ,  903 ,  1302 ,  1600 ,  1704  maintain the location of the soft tissue in front of, or at the tapered end of the interference device  11 ,  41 ,  81 ,  301 ,  601 ,  901 ,  1301 ,  1500 ,  1701  thereby preventing slippage of the tissue past the device  11 ,  41 ,  81 ,  301 ,  601 ,  901 ,  1301 ,  1500 ,  1701  during and after repair. This substantially reduces the possibility of a failed fixation of the tissue to the bone, thereby leading to an unsuccessful repair. 
     For the purposes of this disclosure, the fixation devices and the interference devices are made from a resorbable polymer material. However, a metal material and other non-metal materials, either resorbable or non-resorbable, are also within the scope of this disclosure. In addition, the devices may be made via a molding process or other process known to one of skill in the art. The cannulations and channel may be formed during the molding process or after the molding process by drilling. Furthermore, rather than containing threads, the outer surface of the interference device may include other surface features that would allow engagement of the interference device with the bone tunnel and soft tissue. The threads allow for rotary advancement of the assembly and the soft tissue graft into the tunnel. However, these other surface features may allow for other advancement, such as axial advancement, into the tunnel. Also, the number of surface features may vary. 
     In addition, the fixation devices may be coupled to the interference devices in manners other than those described above. For the purposes of this disclosure, the method and devices, described above, are used in arthroscopic knee repair. However, the method and devices may be used in the repair of other soft tissue. The fixation devices may be of a variety of lengths and may include surface features that mate with surface features located within the cannulations to further couple the fixation devices to the interference devices. The surface features may include threads, barbs, ribs, or other surface features known to one of skill in the art and that have the ability to further facilitate coupling between the fixation devices and the interference devices. It is also within the scope of this disclosure for the fixation devices and/or the interference devices to be made out of a material, such as a shape memory material, that expands or otherwise allows for further coupling between the devices in response to body temperature or an external energy source. 
     Furthermore, it is within the scope of  FIGS. 1, 3, and 14  for the fixation devices  12 , 42 , 1600  to be coupled to the interference devices  11 , 41 , 1500  via the use of a hole on the fixation devices  12 , 42 , 1600  that at least the tapered ends  11   d , 41   d , 1502  are disposed within, rather than using the shafts  12   c , 42   c , couplers  12   d , 42   d , and legs  1600   b . Additionally, it is within the scope of  FIGS. 1, 3, 5, and 14  for the fixation devices  12 ,  42 ,  82 ,  1600  to be coupled to the interference devices  11 ,  41 ,  81 ,  1500  via the use of a shaft that would extend from the coupling portions  12   a ,  42   a ,  82   a ,  1600   a  to be housed within the cannulations  11   b ,  41   b ,  81   b  of the interference devices  11 ,  41 ,  81 ,  1500 . 
     Additionally, it is within the scope of this disclosure for the top portion  604  of fixation device  602  and fixation devices  903 , 1302  to have a length that extends either an entire length or a partial length of the interference devices  301 , 601 , 901 , 1301 . 
     As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the disclosure, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.