Abstract:
A tissue anchor insertion tool includes a first member defining a region configured to receive a tissue anchor, and a second member positioned to substantially cover the tissue anchor during introduction to a surgical site. The second member is coupled to the first member such that relative motion between the members deploys the tissue anchor from the region. The first member includes an applicator configured to move laterally to deploy the anchor from the region. A method includes providing first and second members coupled for relative motion, inserting a tissue anchor into tissue using the first and second members, and relatively moving the first and second members to deploy the tissue anchor from the first member. The tissue anchor is mounted to the first member. The second member substantially covers the tissue anchor during the insertion into tissue.

Description:
BACKGROUND  
         [0001]    This invention relates to tissue anchor insertion tools.  
           [0002]    Ligaments and tendons, after they have torn away from bone, can be reattached arthroscopically using suture. Traditionally, a surgeon inserts a suture anchor with an attached suture into the bone and ties the suture about the ligament or tendon to secure the ligament or tendon to the bone. The suture anchor is deployed within the bone in a manner that resists pull-out from the bone in response to forces exerted during healing that tend to draw the reattached ligament or tendon, and thus the suture and suture anchor, away from the bone.  
         SUMMARY  
         [0003]    According to one aspect of the invention, a tissue anchor insertion tool includes a first member defining a region configured to receive a tissue anchor, and a second member positioned to substantially cover the tissue anchor during introduction to a surgical site. The second member is coupled to the first member such that relative motion between the members deploys the tissue anchor from the region.  
           [0004]    Embodiments of this aspect of the invention may include one or more of the following features. The first member includes an applicator, and the second member includes a flexor. The members are coupled by engagement of the flexor and the applicator. The applicator includes a straight portion and a ramped portion. The applicator, e.g., a spring, includes a first end portion fixed to the first member and a second end portion extending into the region to engage the tissue anchor. The applicator is configured to move laterally to a direction of relative motion between the members. The flexor includes a pin coupled to the second member for movement with the second member relative to the applicator. The first member defines an opening for receiving the pin.  
           [0005]    The first member includes first and second distal prongs defining the region configured to receive a tissue anchor therebetween. The prongs each define arcuate surfaces for receiving the tissue anchor. The second member includes a tubular element substantially surrounding the first member. The tissue anchor insertion tool further includes a contact extending between the first and second members. Actuation of the contact causes relative motion between the first member and the second member. The contact is fixed to the second member. The first member defines a slot for receiving at least a portion of the contact. The tissue anchor insertion tool further includes a handle and a coupling between the handle and the first member preventing relative rotation therebetween.  
           [0006]    The tissue anchor insertion tool includes means for applying a lateral force to the tissue anchor. The means includes an applicator and a flexor for flexing the applicator.  
           [0007]    According to another aspect of the invention, a tissue anchor insertion tool includes a first member including an applicator and defining a region configured to receive a tissue anchor, and a second member including a flexor and positioned to substantially cover the tissue anchor during introduction to a surgical site. The applicator is configured to move laterally to deploy the tissue anchor from the region. The members are coupled by engagement of the flexor and the applicator such that relative motion between the members causes the applicator to move laterally to deploy the tissue anchor from the region.  
           [0008]    According to another aspect of the invention, an anchor and tool assembly includes a tissue anchor, a first member receiving the tissue anchor, and a second member positioned to substantially cover the tissue anchor during introduction to a surgical site and coupled to the first member such that relative motion between the members deploys the tissue anchor from the first member.  
           [0009]    According to another aspect of the invention, a tissue anchor insertion tool includes a member defining a region configured to receive a tissue anchor to deliver the tissue anchor to an insertion site. The member includes an applicator configured to move laterally to deploy the anchor from the region configured to receive the tissue anchor.  
           [0010]    Embodiments of this aspect of the invention may include one or more of the following features. The tissue anchor insertion tool includes a movable element coupled to the member for movement relative to the member between an extended position and a retracted position. The movable element substantially covers the tissue anchor when in the extended position, and substantially uncovers the tissue anchor when in the retracted position. The movable element includes a flexor coupled to the applicator to laterally move the applicator upon axial movement of the movable element. The applicator includes a straight portion permitting movement of the flexor relative to the applicator without lateral movement of the applicator. The applicator includes a ramped portion, and movement of the flexor along the ramped portion laterally deflects the applicator.  
           [0011]    According to another aspect of the invention, a method includes providing first and second members coupled for relative motion, inserting a tissue anchor into tissue using the first and second members, and relatively moving the first and second members to deploy the tissue anchor from the first member. The tissue anchor is mounted to the first member. The second member substantially covers the tissue anchor during the insertion into tissue  
           [0012]    Embodiments of this aspect of the invention may include one or more of the following features. The step of relatively moving includes proximally moving the second member relative to the first member. The step of relatively moving uncovers the tissue anchor. Deploying the tissue anchor includes moving an applicator laterally to engage the tissue anchor. Engaging the tissue anchor rotates the tissue anchor.  
           [0013]    According to another aspect of the invention, a method includes inserting a tissue anchor into tissue, and moving an applicator laterally to rotate the tissue anchor during deployment of the tissue anchor into tissue.  
           [0014]    Embodiments of this aspect of the invention may include covering the tissue anchor during insertion of the tissue anchor into tissue.  
           [0015]    The tissue anchor insertion tool enables arthroscopic placement of a tissue anchor that needs to be rotated when implanted. The insertion tool applies a lateral force to the tissue anchor to rotate the anchor, deploying the anchor during an arthroscopic surgical procedure. The tissue anchor is covered during advancement into the tissue, allowing an operator to properly position the insertion tool while limiting the chance of dislodging the tissue anchor from the insertion tool.  
           [0016]    The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent form the description and drawings, and from the claims. 
       
    
    
     DESCRIPTION OF DRAWINGS  
       [0017]    [0017]FIG. 1 is a side view of a tissue anchor insertion tool according to the present invention;  
         [0018]    [0018]FIG. 2A is an exploded view of the insertion tool;  
         [0019]    [0019]FIG. 2B is an enlarged view of section  2 B of FIG. 2A;  
         [0020]    [0020]FIG. 3A illustrates a distal end of a cover of the insertion tool;  
         [0021]    [0021]FIG. 3B is a cross-sectional side view of the cover;  
         [0022]    [0022]FIG. 4 is a cross-sectional side view of a shaft of the insertion tool;  
         [0023]    [0023]FIG. 5A illustrates a thumb contact region of the insertion tool;  
         [0024]    [0024]FIG. 5B is a cross-sectional side view of the thumb contact region of the insertion tool taken along lines  5 B- 5 B of FIG. 5A;  
         [0025]    [0025]FIG. 6 is a cross-sectional side view of a distal region of the insertion tool;  
         [0026]    [0026]FIG. 7 illustrates a tissue anchor for use with the insertion tool;  
         [0027]    FIGS.  8 A- 8 C are side views of the insertion tool shown at various stages during deployment of the tissue anchor; and  
         [0028]    [0028]FIGS. 9A and 9B illustrate deployment of the tissue anchor in bone. 
     
    
     DETAILED DESCRIPTION  
       [0029]    Referring to FIG. 1, an anchor insertion tool  1  arthroscopically deploys a tissue anchor  100 , e.g., the RotorloC™ Anchor available from Smith &amp; Nephew Endoscopy, Andover, Mass., by axially advancing the anchor into a bone hole and applying a lateral force to the anchor to rotate the anchor. Tool  1  includes a handle  2  joined to an elongate portion  13  terminating in a distal region  99  housing tissue anchor  100 . Elongate portion  13  includes an adapter  14  that is coupled to handle  2 , a shaft  3  coupled to adapter  14 , and a tubular cover  4  surrounding shaft  3 . Cover  4  is coupled to adapter  14  to slide relative to adapter  14 , as described below. Tissue anchor  100  is located within shaft  3  and substantially covered by cover  4  during introduction to a surgical site.  
         [0030]    Referring to FIGS. 2A, 3A and  3 B, cover  4  is a tubular member having a wall  200  defining a lumen  18  for receiving shaft  3 , and a slot  19  extending through wall  200  along the entire length of cover  4 . Opposite slot  19 , an additional slot  20  extends through wall  200  over a length of about 5 to 15 mm, preferably about 10 mm, from a distal end  202  of cover  4 , for purposes described below. Extending from wall  200  into lumen  18  is a guide  204 .  
         [0031]    Referring to FIGS. 2A and 4, shaft  3  is a solid member with a first slot  24  in an exterior surface  210  of the shaft, and an opposite slot  25  in the exterior surface  210  of the shaft. Slot  24  extends the entire length of shaft  3 . Guide  204  is received within shaft slot  25  limiting relative rotation between shaft  3  and cover  4  while allowing relative axial motion. Slot  25  extends up to about 150 mm, preferably about 95 mm, from distal end  203  of shaft  3 , and guide  204  is spaced about 100 mm, preferably about 65 mm, from distal end  202 . The relative length of slot  25  and positioning of guide  204  provides clearance for a desired amount of relative axial motion between shaft  3  and cover  4 .  
         [0032]    The depth of shaft slot  25  is increased in a distal region  212  of shaft  3  over a length L1 of about 20 to 50 mm, preferably about 35 mm to form a chamber  214 , for purposes described below. The width of shaft slot  25  is increased in distal region  212  of the shaft over a length L2 of about 10 to 30 mm, preferably about 20 mm, to form a cutout  130  having distal and proximal ends  133 ,  144 , respectively, for purposes described below.  
         [0033]    Referring to FIGS. 2A and 5B, adapter  14  includes a coupling portion  7  received within a bore  220  in handle  2  and fixed to handle  2  by, e.g., epoxy. Coupling portion  7  defines a slot  250 . Adapter  14  has a wall  230  defining a bore  61  and a slot  62  extending from bore  61  through wall  230 . Slot  62  is aligned with slot  250 . Opposite slot  62 , an axial nub  90  extends from wall  230  into bore  61  and runs the length of adapter  14 . Shaft  3  has an additional slot  232  opposite slot  24  that receives nub  90  when the proximal end  31  of shaft  3  is slid into bore  61 . The placement of nub  90  within slot  232  limits relative rotation between shaft  3  and adapter  14 .  
         [0034]    Referring to FIGS. 5A and 5B, cover  4  is coupled to adaptor  14  by a resilient thumb contact  9 . Contact  9  extends from a proximal end  27  of cover  4  to a guide channel  41  defined in adapter  14 . Contact  9  includes a mating member  15  supporting a nub  21  that is received in guide channel  41 . Guide channel  41  has a race-track shape with proximal and distal portions  43 ,  44 , respectively, and side portions  42 ,  42 ′. In an unstressed state, contact  9  is straight with nub  21  in the middle of portion  43  or  44 . To axially move cover  4 , the operator flexes contact  9  sideways to align nub  21  with side portion  42  or  42 ′ and moves nub  21  axially along side portion  42  or  42 ′. When nub  21  has been moved the full length of the side portion, contact  9  springs back to a straight orientation returning nub  21  to the middle of portion  43  or  44 . This spring action provides positive control on the relative motion between cover  4  and shaft  3 . The distance between proximal and distal portions  43 ,  44  is, e.g., about 10 to 20 mm, preferably about 15 mm, and defines the range over which cover  4  can be slid relative to shaft  3 .  
         [0035]    Referring to FIGS. 2B and 6, cover  4  includes a flexor, e.g., a pin  12 , and shaft  3  includes an applicator, e.g., a spring  5  located within chamber  214 . Pin  12  and spring  5  couple cover  4  and shaft  3  such that retraction of cover  4  relative to shaft  3  causes lateral deflection of spring  5 , as described below. Spring  5  is received within shaft chamber  214  and has a proximal end  54  attached to shaft  3  by e.g., epoxy, and a free distal end  51 . Cover  4  defines a pair of opposing holes  122  in which pin  12  is received such that pin  12  extends through lumen  18 . As shown in FIG. 6, pin  12  is received within cutout  130  between shaft  3  and spring  5  and contacts a surface  52  of spring  5 . The length of cutout  130  provides clearance for desired axial motion of pin  12 .  
         [0036]    Spring  5  is contoured to control lateral flexing of spring  5  as pin  12  is moved along surface  52  of spring  5 . From distal end  51  to proximal end  54 , spring  5  includes an arcuate portion  6  that engages anchor  100 , a straight portion  7 , a sloped portion  8 , a straight portion  9 , a sloped portion  10 , and a straight portion  11 . When cover  4  is moved relative to shaft  3 , pin  12  slides along surface  52  of spring  5 . When pin  12  engages portion  10  of spring  5 , spring  5  deflects laterally, moving distal end  51  of spring  5  laterally against anchor  100  to deploy anchor  100  from tool  1 , as described further below.  
         [0037]    Shaft  3  includes a pair of opposing, spaced apart arms  119 ,  120  that define an anchor receiving region  121  therebetween. Each arm  119 ,  120  has an internal pivot face  123  bounded by an arcuate edge  125 . Tissue anchor  100  is coupled to shaft  3  by placement between arms  119 ,  120  in abutment with faces  123 . Free end  54  of spring  5  extends into region  121  and contacts anchor  100 . Referring also to FIG. 7, tissue anchor  100  includes a central portion  105  with an opposing pair of pivoting faces  108 ,  109 . Each pivoting face  108 ,  109  includes a raised arcuate lip  112  with a radius of curvature substantially equal to the radius of curvature of arcuate edges  125  of arms  119 ,  120 . When assembled, faces  123  of arms  119 ,  120  are positioned against anchor faces  108 ,  109 , with edges  125  against lips  112 . Due to the shapes of edges  125  and lips  112 , anchor  100  can rotate relative to arms  119 ,  120 . Lip  112  does not define a complete circle about faces  108 ,  109  such that anchor  100  has an opening  242  to each of faces  108 ,  109 . When anchor  100  is slid between arms  119 ,  120 , arm pivot faces  123  pass through openings  242  into position against anchor faces  108 ,  109 . Anchor  100  is maintained in position between arms  119 ,  120  by the engagement of lips  112  with edges  125 , and by the positioning of cover  4  about anchor  100 .  
         [0038]    Tissue anchor  100  includes a pair of wings  101 ,  102  with oppositely oriented, angled cutting edges  97 ,  98 , respectively. As shown in FIG. 6, central portion  105  of tissue anchor  100  defines a pair of suture channels  103 ,  104  for receiving two suture strands  128  (only one suture strand being shown). When assembled, with suture strands  128  threaded through channels  103 ,  104 , suture  128  passes between arms  119 ,  120  to slot  24 , and along slot  24  to adapter slot  250 . At the end of each suture strand there is a needle  129 ,  129 ′. Handle  2  has a face  2   a  defining four slots  254  (FIG. 2A) in which the needles are located during introduction of anchor  100  into tissue.  
         [0039]    Referring to FIGS. 8A and 9A, during introduction of tool  1  into tissue, mating member  15  is in contact with distal face  44  of guide channel  41  and pin  12  is near distal end  133  of cutout  130  such that cover  4  is disposed distally to substantially cover tissue anchor  100 . Spring  5  rests against tissue anchor  100  without exerting a lateral force on the anchor, and pin  12  contacts face  52  of spring  5  at the junction of spring portions  8  and  9 . The position of cover  4  over anchor  100  limits possible dislodgement of anchor  100  from tool  1  during introduction into the tissue, and protects the tissue from the anchor.  
         [0040]    Referring to FIG. 8B, to deploy the anchor, the operator first slides member  15  and thus cover  4  proximally to a position near the middle of the slidable range (i.e., member  15  is near the middle of guide channel  41  and pin  12  is near the middle of cutout  130 ). Pin  12  now contacts spring  5  at the junction of spring portions  9  and  10 , and anchor  100  is partially uncovered. Since spring portion  9  is oriented parallel to the axis of elongate portion  13 , the movement of pin  12  does not deflect spring  5  and spring  5  still rests against tissue anchor  100  without exerting a lateral force on the anchor.  
         [0041]    Referring to FIGS. 8C and 9B, to rotate anchor  100  (arrow A), the operator slides member  15  and thus cover  4  further proximally such that member  15  is in contact with proximal face  43  of guide channel  41  and pin  12  is near distal end  144  of cutout  130 . Anchor  100  is now fully uncovered. The movement of pin  12  along sloped spring portion  10  laterally deflects spring  5 . Spring portions  8  and  9  are received within cover slot  20 , and distal spring portion  6  exerts a substantially laterally directed force, F, on anchor  100  causing the anchor to rotate. The rotation of tissue anchor  100  pivots anchor  100  within arms  119 ,  120 . The proximal translation of cover  4  thus both exposes and rotates anchor  100 .  
         [0042]    Referring to FIGS. 9A and 9B, in use, e.g., in shoulder repair, with a cannula  40  placed through a skin portal  240 , the operator advances tissue anchor insertion tool  1  through cannula  40  to a predrilled hole  32  in a tissue  30 , e.g., bone tissue. The operator then moves member  15  proximally to channel portion  44 , thus moving cover  4  proximally, while pushing insertion tool  1  into hole  30 . This results in shaft  3  entering the bone hole with the distal end of cover  4  abutting the bone surface  30   a,  and anchor  100  is uncovered and rotated, as described above, with the ends of tissue anchor wings  101 ,  102  starting to push into the bone tissue surrounding hole  32 . The operator then applies a torque to handle  2  to rotate insertion tool  1  and tissue anchor  100 , arrow B. The applied torque causes edges  97 ,  98  of anchor  100  to cut into the bone tissue, and, because the cutting edges are set at an angle, the rotation of anchor  100  along arrow B results in additional rotation of anchor  100  along arrow A. About 1½ turns of tool  1  rotates anchor  100  such that anchor wings  101 ,  102  are embedded in the bone tissue and oriented substantially perpendicular to the bone wall. The rotation of anchor  100  to this perpendicular position aligns anchor face openings  242  with arms  119 ,  120  such that arms  119 ,  120  can be slid from anchor  100  through openings  242 . Thus, to release anchor  100  from shaft  3 , the operator simply moves tool  1  proximally.  
         [0043]    Other embodiments are within the scope of the following claims.