Abstract:
A method for repairing a cartilage defect according to an exemplary aspect of the present disclosure includes, among other things, preparing a cartilage defect for implantation of a cartilage graft and attaching the cartilage graft to bone using at least one knotless suture anchor.

Description:
BACKGROUND 
       [0001]    This disclosure relates to a surgical method for knotlessly fixating a cartilage graft to bone to repair a cartilage defect. 
         [0002]    Repetitive trauma to a joint, such as a knee, ankle, hip or shoulder joint, may cause cartilage defects. Cartilage defects include localized areas of damaged articular cartilage and, potentially, adjacent subchondral bone. Cartilage defects typically do not heal without treatment. If not treated, the defect could further deteriorate the articulate cartilage and/or underlying bone of the joint, thereby causing relatively significant arthritic pain in some individuals. 
       SUMMARY 
       [0003]    A method for repairing a cartilage defect according to an exemplary aspect of the present disclosure includes, among other things, preparing a cartilage defect for implantation of a cartilage graft and attaching the cartilage graft to bone using at least one knotless suture anchor. 
         [0004]    In a further non-limiting embodiment of the foregoing method, the preparing step includes creating vertical margins around a periphery of the cartilage defect. 
         [0005]    In a further non-limiting embodiment of either of the foregoing methods, the preparing step includes removing at least a portion of the cartilage defect using a curette. 
         [0006]    In a further non-limiting embodiment of any of the foregoing methods, the preparing step includes performing bone marrow stimulation to the cartilage defect. 
         [0007]    In a further non-limiting embodiment of any of the foregoing methods, the step of performing the bone marrow stimulation includes performing a microfracture procedure. 
         [0008]    In a further non-limiting embodiment of any of the foregoing methods, the preparing step includes drying the cartilage defect. 
         [0009]    In a further non-limiting embodiment of any of the foregoing methods, the attaching step includes passing a flexible strand through the cartilage graft, loading a free end of the flexible strand through a portion of the at least one knotless suture anchor, tensioning the flexible strand to approximate the cartilage graft to the bone and inserting the at least one knotless suture anchor into the bone to knotlessly fixate the cartilage graft to the bone. 
         [0010]    In a further non-limiting embodiment of any of the foregoing methods, the inserting step includes moving an anchor body of the at least one knotless suture anchor toward the portion inside the bone to trap the flexible strand between the bone and the anchor body. 
         [0011]    In a further non-limiting embodiment of any of the foregoing methods, the attaching step includes implanting the at least one knotless suture anchor into the bone, passing a flexible strand of the at least one knotless suture anchor through the cartilage graft and tensioning the flexible strand to approximate the cartilage graft to the bone. 
         [0012]    In a further non-limiting embodiment of any of the foregoing methods, the tensioning step includes shuttling a free end of the flexible strand through the flexible strand to create a spliced loop around the cartilage graft. 
         [0013]    In a further non-limiting embodiment of any of the foregoing methods, the at least one knotless suture anchor includes a first knotless suture anchor and a second knotless suture anchor. The attaching step includes implanting the first knotless suture anchor into the bone, passing a flexible strand connected to the first knotless suture anchor through the cartilage graft and tensioning the flexible strand to approximate the cartilage graft to the bone. 
         [0014]    In a further non-limiting embodiment of any of the foregoing methods, the attaching step includes passing a second flexible strand through the cartilage graft, loading the second flexible strand through a portion of the second knotless suture anchor, tensioning the second flexible strand and inserting the second knotless suture anchor into bone. 
         [0015]    In a further non-limiting embodiment of any of the foregoing methods, at least one of the first knotless suture anchor and the second knotless suture anchor is a soft knotless anchor assembly. 
         [0016]    In a further non-limiting embodiment of any of the foregoing methods, at least one of the first knotless suture anchor and the second knotless suture anchor includes an eyelet. 
         [0017]    In a further non-limiting embodiment of any of the foregoing methods, at least one of the first knotless suture anchor and the second knotless suture anchor includes a shuttle device configured to shuttle the flexible strand. 
         [0018]    A method for repairing a cartilage defect according to another exemplary aspect of the present disclosure includes, among other things, passing a flexible strand through a cartilage graft, tensioning the flexible strand to approximate the cartilage graft relative to bone associated with the cartilage defect and inserting a knotless suture anchor into the bone to knotlessly fixate the cartilage graft to the bone. 
         [0019]    In a further non-limiting embodiment of the foregoing method, the method includes creating a pilot hole in the bone prior to the step of inserting the knotless suture anchor. 
         [0020]    In a further non-limiting embodiment of either of the foregoing methods, the tensioning step occurs before the inserting step. 
         [0021]    In a further non-limiting embodiment of any of the foregoing methods, the tensioning step occurs after the inserting step. 
         [0022]    In a further non-limiting embodiment of any of the foregoing methods, the method includes loading a free end of the flexible strand through a portion of the knotless suture anchor. 
         [0023]    The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
         [0024]    The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]      FIGS. 1 and 2  schematically illustrate preparing a cartilage defect for implantation of a cartilage graft. 
           [0026]      FIG. 3  illustrates an exemplary cartilage graft. 
           [0027]      FIGS. 4A, 4B, 4C and 4D  schematically illustrate knotlessly fixating a cartilage graft to bone according to a first embodiment of this disclosure. 
           [0028]      FIGS. 5A, 5B and 5C  schematically illustrate knotlessly fixating a cartilage graft to bone according to a second embodiment of this disclosure. 
           [0029]      FIGS. 6A, 6B, 6C and 6D  illustrate exemplary fixation patterns for fixating a cartilage graft to a bone. 
           [0030]      FIG. 7  illustrates applying a layer of fibrin over a repaired cartilage defect. 
           [0031]      FIG. 8  illustrates a knotless suture anchor according to a first embodiment of this disclosure. 
           [0032]      FIGS. 9 and 10  illustrate a knotless suture anchor according to a second embodiment of this disclosure. 
           [0033]      FIGS. 11 and 12  illustrate a knotless suture anchor according to yet another embodiment of this disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    This disclosure describes surgical methods for repairing cartilage defects. The surgical methods include attaching a cartilage graft to bone using at least one knotless suture anchor. In some embodiments, the knotless suture anchor is implanted into bone before tensioning a flexible strand, such as a suture, to approximate the cartilage graft to the bone. In other embodiments, the knotless suture anchor is implanted into bone after tensioning the flexible strand to approximate the cartilage graft to the bone. These and other features are described in greater detail in the following paragraphs of this detailed description. 
         [0035]      FIGS. 1-7  schematically illustrate a method of repairing a cartilage defect  10  located within a joint  12 . The method is illustrated and described as an arthroscopic method; however, the method could alternatively be performed as an open procedure. The cartilage defect  10  can include osteochondral and/or chondral defects. In other words, the cartilage defect  10  may include localized areas of damaged articular cartridge and/or damaged subchondral bone of the joint  12 . In one embodiment, the joint  12  is a knee joint. However, the methods of this disclosure may be used to repair cartilage defects located anywhere within the human body. 
         [0036]    The exemplary repair method begins by prepping the cartilage defect  10  for receiving a cartilage graft  28  (shown in  FIG. 3 ). Referring first to  FIG. 1 , after the surgeon has identified the cartilage defect  10  within the joint  12 , the cartilage defect  10  may be debrided to a stable border having perpendicular margins. Tools, such as a curette  14  and an elevator  16 , can be used to create vertical margins around a periphery of the cartilage defect  10 . 
         [0037]    The cartilage defect  10  may be prepped with our without bone marrow stimulation. In one non-limiting embodiment, the cartilage defect  10  is further prepped by performing bone marrow stimulation. For example, as shown in  FIG. 2 , a microfracture procedure or some other technique may optionally be performed to obtain a bleeding bone bed  18 . During the microfracture surgery, multiple perforations  20  are created in subchondral bone  22  that extends beneath the articular cartilage  24  associated with the cartilage defect  10 . The bleeding bone bed  18  may be created using a tool  26 , such as Arthrex&#39;s Powerpick™, to create the perforations  20 . Formation of the perforations  20  creates the bleeding bone bed  18 , which stimulates bone marrow seepage at the repair site. Other techniques can also be used to create the bleeding bone bed  18 , including but not limited to, drilling, hammering, curetting, scraping, etc. 
         [0038]    The cartilage defect  10  may also be dried to complete surgical preparation of the cartilage defect  10 . The cartilage defect  10  is dried to remove excess moisture that could interfere with implantation of the cartilage graft  28 . The cartilage defect  10  may be dried using any known technique. 
         [0039]    The cartilage graft  28  may be knotlessly implanted after adequately prepping the cartilage defect  10 . The cartilage graft  28  serves as a scaffold over the cartilage defect  10 , thereby providing a tissue network that can potentially signal autologous cellular interactions. The size and shape of the cartilage graft  28  may be selected using a template that is placed over the cartilage defect  10  and marked to indicate its general size. The template may then be used to trim to cartilage graft  28  down to the desired size and shape. 
         [0040]    One exemplary cartilage graft  28  is illustrated in  FIG. 3 . In one non-limiting embodiment, the cartilage graft  28  includes a cartilage disk  29  having a plurality of pores  31  formed through the cartilage disk  29 . The cartilage graft  28  may be made of human tissue (e.g., allograft cartilage), synthetic materials, xeno materials, etc. In one non-limiting embodiment, the cartilage graft  28  is made of a micronized cartilage matrix. Although shown as being porous, the cartilage graft  28  is not limited to such an embodiment. 
         [0041]      FIGS. 4A-4D  illustrate a first non-limiting embodiment for knotlessly attaching the cartilage graft  28  to a bone B using a knotless suture anchor  30 A. The cartilage graft  28  may be secured to subchondral bone  22  that is associated with the cartilage defect  10  and which has been previously exposed during one or more of the method steps shown in  FIGS. 1 and 2 . 
         [0042]    First, as shown in  FIG. 4A , a flexible strand  32 , such as a suture, is passed through the cartilage graft  28 . A mattress stitch  33  may be formed to connect the flexible strand  32  to the cartilage graft  28 . The mattress stitch  33  is formed by inserting the flexible strand  32  through a pore  31 A in a direction from the bottom  35  toward a top  37  of the disk  29  of the cartilage graft  28  and then inserting the flexible strand  32  through an adjacent pore  31 B in a direction from the top  37  toward the bottom  35  of the disk  29 . Other suturing techniques and configurations are also contemplated within the scope of this disclosure. For example, in situations where the cartilage graft  28  is not porous, the flexible strand  32  may be simply threaded through the cartilage graft  28 . 
         [0043]    Next, as shown in  FIG. 4B , one or more free ends  34  of the flexible strand  32  are loaded through a portion  35  of the knotless suture anchor  30 A. In one non-limiting embodiment, the portion  35  includes an eyelet  36  of the knotless suture anchor  30 A. The eyelet  36  may next be inserted into the bone B, as shown in  FIG. 4C . The eyelet  36  can be inserted into a pilot hole  38  that is pre-formed in the bone B or the eyelet  36  itself can form the pilot hole  38 . Once the eyelet  36  is positioned at least partially in the pilot hole  38 , the flexible strand  32  may be tensioned in a direction D 1  to approximate the cartilage graft  28  to the bone B. In one embodiment, tensioning the flexible strand  32  positions the cartilage graft  28  in place over the subchondral bone  22  that is associated with the cartilage defect  10 . 
         [0044]    Finally, as shown in  FIG. 4D , the knotless suture anchor  30 A is inserted into the bone B to knotlessly fixate the cartilage graft  28  to the bone B. For example, an anchor body  39  of the knotless suture anchor  30 A may be moved toward the eyelet  36  to trap the flexible strand  32  between the bone B and the anchor body  39  in order to fixate the cartilage graft  28  in place. Free ends  34  of the flexible strand  32  may be trimmed flush to the cartilage graft  28 . The procedure illustrated in  FIGS. 4A-4D  can be repeated to implant multiple knotless suture anchors  30 A to fixate the cartilage graft  28  in place. 
         [0045]      FIGS. 5A-5C  illustrate another non-limiting embodiment for knotlessly fixating the cartilage graft  28  to bone B. In this embodiment, a knotless suture anchor  30 B is first inserted into the bone B (see  FIG. 5A ). A pilot hole  38  may optionally be pre-formed into the bone B for receiving the knotless suture anchor  30 B. A flexible strand  32  that is connected to the knotless suture anchor  30  may next be passed through the cartilage graft  28  (see  FIG. 5B ). For example, the flexible strand  32  may be looped through one or more pores  31  of the cartilage graft  28 . Finally, as shown in  FIG. 5C , the flexible strand  32  may be tensioned to approximate the cartilage graft  28  to the bone B. In one embodiment, tensioning the flexible strand  32  shuttles the flexible strand  32  through the knotless suture anchor  30 B to tighten the cartilage graft  28  down over the subchondral bone  22  that is associated with the cartilage defect  10 . The procedure illustrated in  FIGS. 5A-5C  can be repeated to implant multiple knotless suture anchors  30 B to fixate the cartilage graft  28  in place. 
         [0046]    The techniques shown in  FIGS. 4A-4D and 5A-5C  are considered “knotless” because there is no need to tie knots in the flexible strand  32  in order to secure the cartilage graft  28  to the bone B. In another non-limiting embodiment, both the technique described by  FIGS. 4A-4D  and the technique described by  FIGS. 5A-5C  may be utilized to fixate the cartilage graft  28  to the bone B. In other words, a combination of different types of knotless suture anchors may be utilized to fixate the cartilage graft  28 . 
         [0047]    Multiple different fixation patterns may be used to secure the cartilage graft  28  to the bone B. For example, the cartilage graft  28  can be fixated by positioning flexible strands  32  at each of its four quadrants (see  FIG. 6A ), through its center and about its periphery (see  FIG. 6B ), through its top and bottom halves (see  FIG. 6C ), or at each third of the cartilage graft  28  (see  FIG. 6D ). Other fixation patterns could also be used. 
         [0048]    In another embodiment, as shown in  FIG. 7 , a layer of fibrin  50  may be applied over the cartilage graft  28  after it has been fixated to bone B. The fibrin  50  may be applied using an applicator  52 . After the fibrin  50  and the cartilage graft  28  sit for a predefined amount of time, such as approximately five minutes, the joint  12  may be gently ranged before closure to assure adherence of the fibrin  50  and the cartilage graft  28  to the bone B. 
         [0049]      FIGS. 8-12  illustrate exemplary knotless suture anchors that can be used in the cartilage defect repair methods described above. Knotless suture anchors similar to those shown in  FIGS. 8-12  may be utilized alone or in combination with one another to fixate a cartilage graft to bone. 
         [0050]    Referring first to  FIG. 8 , the knotless suture anchor  30 A includes an anchor body  39  and an eyelet  36 . The anchor body  39  is pre-loaded onto a driver  100 . The anchor body  39  may be configured as a screw or an interference plug which are appropriately cannulated for receiving a shaft  99  of the driver  100 . The eyelet  36  may be provided at a distal end  102  of driver  100 . The eyelet  36  is releasably attached to the distal end  102  of driver  100 . The eyelet  36  includes an aperture  104  for receiving one or more flexible strands (see, for example, the flexible strand  32  shown in  FIG. 4B ). 
         [0051]      FIGS. 9-10  illustrate another knotless suture anchor  30 B. In this embodiment, the knotless suture anchor  30 B includes an anchor body  41  and a flexible strand  43  that extends inside of the anchor body  41 . A shuttle device  45 , such as a nitinol wire, is also received inside the anchor body  41 . The shuttle device  45  may be pre-assembled to the flexible strand  43  as shown in  FIG. 9  and will form a spliced loop  47  as shown in  FIG. 10  after the flexible strand  43  is shuttled through itself. For example, a free end  49  of flexible strand  43  is passed through eyelet  51  of the shuttle device  45  (in the direction of arrow A of  FIG. 9 ) and then the shuttle device  45  is pulled to allow flexible strand  43  to pass through itself at region  53  (see  FIG. 10 ) and form the spliced loop  47 . The perimeter of spliced loop  47  is adjustable to allow the construct to be self-cinching and to adjust the tension on the cartilage graft that is to be fixated. 
         [0052]      FIGS. 11-12  illustrates yet another knotless suture anchor  30 C. In this embodiment, the knotless suture anchor  30 C is a “soft” anchor assembly formed of soft materials such as yams, fibers, filaments, strings, fibrils, strands, sutures, etc., or any combination of such materials. The soft materials may be synthetic or natural materials, or combinations of synthetic and natural materials, and may be bio-degradable or non-degradable within the scope of this disclosure. In one non-limiting embodiment, the knotless suture anchor  30 C is made exclusively of soft, suture-based materials. 
         [0053]    The knotless suture anchor  30 C includes an anchor body  55  and a flexible strand  57  received through the anchor body  55 . The flexible strand  57  includes an eyelet  59  (located at one end of the strand) that is preloaded with a shuttle device  61  attached at the portion of the flexible strand  57  that exits the anchor body  55  (for example, at a portion of the other end of the strand). In one embodiment, the shuttle device  61  is a nitinol passing wire. The shuttle device  61  may be pre-assembled to the flexible strand  57  as shown in  FIG. 11  and will form a spliced loop  63  as shown in  FIG. 12  after the flexible strand  57  is shuttled through itself. For example, a free end  65  of flexible strand  57  is passed through eyelet  69  of the shuttle device  61  (in the direction of arrow A of  FIG. 11 ) and then the shuttle device  61  is pulled to allow flexible strand  57  to pass through itself at region  67  (see  FIG. 12 ) and form the spliced loop  63 . The perimeter of spliced loop  63  is adjustable to allow the construct to be self-cinching and to adjust the tension on the cartilage graft to be fixated. 
         [0054]    Although the different non-limiting embodiments are illustrated as having specific components, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
         [0055]    It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure. 
         [0056]    The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.