Patent Publication Number: US-2023157682-A1

Title: Suture anchor and laceration repair device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of International Application PCT/JP2020/030384, with an international filing date of Aug. 7, 2020, which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a suture anchor and a laceration repair device. 
     BACKGROUND ART 
     In the related art, there are a known device and method for repairing a wound in tissue such as a knee joint meniscus (for example, see PTL 1). The device of PTL 1 includes a first securing member, a second securing member, and a suture connected to the first securing member and the second securing member. The suture is secured to the first securing member and is movable with respect to the second securing member. The first securing member and the second securing member pass through the tissue and are disposed on a surface of the tissue so that a portion of the suture between the first securing member and the second securing member crosses the wound, the suture is subsequently pulled, and thus, the wound is closed. 
     CITATION LIST 
     Patent Literature 
     
         
         {PTL 1} Publication of Japanese Patent No. 4160386 
       
    
     SUMMARY 
     An aspect of the present invention is a suture anchor including: a plate-like base that has an upper side and a lower side in a thickness direction of the base and that has one end and the other end in a direction intersecting the thickness direction; a deformable portion disposed at an upper side of the base, at least a side of the other end of the deformable portion being disposed so as to be separated by a space from the base; and a first passage and a second passage each formed in the base to allow a suture to pass therethrough, wherein the deformable portion is a cantilever state having a fixed end, which is disposed at a side of the one end and fixed to the base, and a free end, which is disposed at a side of the other end, and the deformable portion is deformable in a direction in which the free end approaches the base, the first passage communicates the upper side and the lower side of the base, the second passage is formed on a side of the one end relative to the free end and the first passage and communicates the space and a side of the one end of the fixed end, and the deformable portion is deformed due to a tensile force applied to the suture, which extends from the first passage and returns to the first passage via a side of the other end relative to the deformable portion, an opposite side of the deformable portion when seen from the base, a side of the one end relative to the deformable portion, the second passage, and the space, and to hold the suture between the deformable portion and the base. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a configuration diagram showing, in outline, a laceration repair device according to an embodiment of the present invention. 
         FIG.  2    is a configuration diagram showing, in outline, a first anchor and a second anchor included in the laceration repair device in  FIG.  1   . 
         FIG.  3 A  is a perspective view of a top surface of a suture anchor according to this embodiment. 
         FIG.  3 B  is a perspective view of a bottom surface of the suture anchor in  FIG.  3 A . 
         FIG.  4 A  is a longitudinal sectional view of the anchor in  FIG.  3 A  taken along I-I in a state in which a deformable portion is not deformed. 
         FIG.  4 B  is a longitudinal sectional view of the anchor in  FIG.  3 A  taken along I-I in a state in which the deformable portion is deformed. 
         FIG.  5 A  is a simplified side view of the anchor in  FIG.  3 A  in the state in which the deformable portion is not deformed. 
         FIG.  5 B  is a simplified side view of the anchor in  FIG.  3 A  in the state in which the deformable portion is deformed. 
         FIG.  6 A  is a diagram for explaining a method for attaching the second anchor to a suture. 
         FIG.  6 B  is a diagram for explaining the method for attaching the second anchor to the suture. 
         FIG.  6 C  is a diagram for explaining the method for attaching the second anchor to the suture. 
         FIG.  6 D  is a diagram for explaining the method for attaching the second anchor to the suture. 
         FIG.  6 E  is a diagram for explaining the method for attaching the second anchor to the suture. 
         FIG.  7    is a flowchart showing a laceration repair method employing the laceration repair device in  FIG.  1   . 
         FIG.  8    is a diagram for explaining the arrangements of knee joint structures, the first anchor, and the second anchor. 
         FIG.  9 A  is a diagram for explaining a step for disposing the first anchor in the method in  FIG.  7   . 
         FIG.  9 B  is a diagram for explaining the step for disposing the first anchor in the method in  FIG.  7   . 
         FIG.  9 C  is a diagram for explaining a step for disposing the second anchor in the method in  FIG.  7   . 
         FIG.  9 D  is a diagram for explaining the step for disposing the second anchor in the method in  FIG.  7   . 
         FIG.  9 E  is a diagram for explaining a step for pulling a free-end portion of the suture in the method in  FIG.  7   . 
         FIG.  9 F  is a diagram for explaining a step for cutting the suture in the method in  FIG.  7   . 
         FIG.  10 A  is a longitudinal sectional view of a meniscus for explaining the arrangements of the first anchor, the second anchor, and the suture. 
         FIG.  10 B  is a longitudinal sectional view of the meniscus for explaining the arrangements of the first anchor, the second anchor, and the suture. 
         FIG.  11 A  is a side view of a modification of the second anchor in which the rigidity of a base is enhanced. 
         FIG.  11 B  is a side view of another modification of the second anchor in which the rigidity of the base is enhanced. 
         FIG.  12    is a side view of a modification of the second anchor subjected to friction increasing treatment. 
         FIG.  13 A  is a side view of another modification of the second anchor provided with a groove in an inner surface of a first passage. 
         FIG.  13 B  is a bottom view of the second anchor in  FIG.  13 A . 
         FIG.  13 C  is a side view of the second anchor in  FIG.  13 A  in a state in which the deformable portion is deformed. 
         FIG.  14 A  is a side view of another modification of the second anchor provided with a groove in an inner surface of a first passage. 
         FIG.  14 B  is a bottom view of the second anchor in  FIG.  14 A . 
         FIG.  15    is a side view of another modification of the second anchor provided with protrusions. 
         FIG.  16 A  is a perspective view of a top surface of another modification of the second anchor. 
         FIG.  16 B  is a perspective view of a bottom surface of the suture anchor in  FIG.  16 A . 
         FIG.  16 C  is a longitudinal sectional view of the suture anchor in  FIG.  16 A  taken along II-II. 
         FIG.  17    is a flowchart showing a laceration repair method according to a comparative example. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     A suture anchor and a laceration repair device according to an embodiment of the present invention will be described below with reference to the drawings. 
     A laceration repair device  1  according to this embodiment is used in laceration repair surgery in which a laceration in soft tissue is sutured by means of a suture  2  to repair the laceration. As shown in  FIG.  1   , the laceration repair device  1  includes a first anchor  11 , a second anchor  12 , the suture  2 , and a delivery device  3 . 
     As shown in  FIG.  2   , the anchors  11  and  12  are attached to the suture  2  and secure the suture  2  to soft tissue so that the suture  2  made to pass through the soft tissue is not removed. The first anchor  11  is secured to a secured end portion  2   a , which is one end portion of the suture  2 , and is disposed on the soft tissue first in the laceration repair surgery. The second anchor  12  is attached to the suture  2  so as to be movable with respect to the suture  2  at a position between the first anchor  11  and a free end portion  2   b , which is the other end portion of the suture  2 , and is disposed on the soft tissue second in the laceration repair surgery. The suture anchor according to the present invention is used as the second anchor  12 . The first anchor  11  is an arbitrary anchor for the suture and may be the suture anchor according to the present invention. 
     The suture  2  is an arbitrary flexible suture that is generally used in suturing soft tissue and is, for example, a suture of size 2.0. 
     The delivery device  3  delivers the anchors  11  and  12  to a surface of the soft tissue via the interior of the soft tissue. The delivery device  3  includes a circular tube-like sheath  4 , an elongated hollow needle  5  having a needle tip  5   a  at a distal end thereof, and a handle  6  connected to a proximal end of the sheath  4 . The needle  5  is accommodated in the sheath  4 , a proximal end of the needle  5  is connected to the handle  6 , and a distal-end portion of the needle  5 , including the needle tip  5   a , protrudes from a distal end of the sheath  4 . 
     The anchors  11  and  12  are loaded into the interior of the needle  5  and are arrayed in the longitudinal direction of the needle  5 . The first anchor  11  is disposed on a distal side of the needle  5 , and the second anchor  12  is disposed on a proximal side of the needle  5 . A side wall of the needle  5  may be provided with a slit that extends toward a proximal end side from the needle tip  5   a  and that extends through the side wall in the radial direction, and the anchors  11  and  12  may be configured so as to be movable along the slit. The suture  2  connected to the anchors  11  and  12  pass through the sheath  4  and are pulled out to the outside from the proximal end of the sheath  4 . 
     An actuator (not shown) for sequentially pushing out the anchors  11  and  12  one at a time from the needle tip  5   a  is provided in the interior of the delivery device  3 . For example, a user can actuate the actuator, for example, by operating an operating member (not shown), such as a slider, provided in the handle  6  to make the first anchor  11  and the second anchor  12  sequentially protrude from the needle tip  5   a.    
     In the example in  FIG.  2   , the first anchor  11  made of a plate-like member and is provided with two holes that respectively extend through the first anchor  11  in a thickness direction thereof. The first anchor  11  is formed of, for example, a resin such as PEEK (polyether ether ketone). 
     As shown in  FIGS.  3 A and  3 B , the suture anchor  12 , which is the second anchor, includes a base  7 , a deformable portion  8 , and two passages  9  and  10  through which the suture  2  passes. At least the deformable portion  8  of the suture anchor  12  is formed of an elastically deformable material, for example, a resin such as PEEK (polyether ether ketone). The base  7  and the deformable portion  8  are, for example, integrally molded using the same material. 
     As will be described later, the deformable portion  8  deforms due to a tensile force of the suture  2  and the suture anchor  12  secures the suture  2  so that the suture  2  does not move with respect to the suture anchor  12  by holding the suture  2  between the base  7  and the deformed deformable portion  8 .  FIGS.  4 A and  5 A  show a state in which the deformable portion  8  is not deformed and  FIGS.  4 B and  5 B  show a state in which the deformable portion  8  is deformed.  FIGS.  4 A and  4 B  are sectional views of the suture anchor  12  and  FIGS.  5 A and  5 B  are simplified side views of the suture anchor  12 . 
     The base  7  is a plate-like member and has a rectangular shape having a longitudinal direction and a transverse direction in a plan view or a bottom view viewed in the thickness direction thereof. The base  7  has an upper side and a lower side in the thickness direction and has one end side and the other end side in the longitudinal direction intersecting the thickness direction. The upper side, the lower side, the one end side, and the other end side of the base  7  respectively correspond to an upper side, a lower side, one end side, and the other end side of the suture anchor  12 , and, in the drawings to which reference is made, the left side is the one end side and the right side is the other end side. 
     In a side view viewed in the transverse direction, a bottom surface  7   b  of the base  7  is a flat surface and a top surface  7   a  of the base  7  is a stepped surface. Specifically, the base  7  at least has a thin portion  71  and a thick portion  72  that is adjacent to the thin portion  71  on the one end side thereof and that protrudes toward the upper side with respect to the thin portion  71 . The base  7  may additionally have a thick end portion  73  that is adjacent to the thin portion  71  on the other end side thereof and that protrudes toward the upper side with respect to the thin portion  71 . 
     The deformable portion  8  is a flat plate-like member that is disposed on the upper side of the base  7  so as to be substantially parallel to the base  7 . The thin portion  71  and the deformable portion  8  of the base  7  face each other in the thickness direction and are separated by a space S through which the suture  2  passes. The deformable portion  8  has a cantilever state that protrudes toward the other end side from a side surface  72   a  of the thick portion  72  of the base  7  and has a secured end  8   a  that is disposed on the one end side and that is secured to the side surface  72   a  of the thick portion  72  and a free end  8   b  that is disposed on the other end side. Due to deflection deformation of the deformable portion  8 , the free end  8   b  approaches the base  7 . The suture  2  passes through the space S once. The dimension of the space S in the thickness direction is greater than the diameter of the suture  2 , and the suture  2  in the space S is movable at least in the longitudinal direction of the base  7  with respect to the base  7 . 
     The first passage  9  is a passage through which the suture  2  passes from the lower side of the base  7  to the upper side thereof and from the upper side to the lower side and that communicates the lower side and the upper side of the base  7 . Specifically, the first passage (first hole)  9  is a hole that extends through the thin portion  71  of the base  7  in the thickness direction and opens in the top surface  7   a  and the bottom surface  7   b . The suture  2  passes through the first passage  9  twice. At least in one radial direction of the first passage  9 , the diameter of the first passage  9  is more than twice as large as the diameter of the suture  2 , and the suture  2  in the first passage  9  is movable in the thickness direction with respect to the base  7 . For example, the first passage  9  has an elliptical shape or an elongated circular shape having a long axis in the longitudinal direction of the base  7 . 
     As will be described later, when attaching the suture anchor  12  to the suture  2 , the free end portion  2   b  of the suture  2  is moved between the lower side of the base  7  and the upper side of the deformable portion  8  via the first passage  9  (see  FIGS.  6 C and  6 D ). In order to facilitate this work, it is preferable that at least a portion of the first passage  9  be formed on a side of the other end with respect to the free end  8   b.    
     In addition, the first passage  9  may extend to the one end side from the other end side with respect to the free end portion  2   b  so that the suture  2  is held at an angular portion between an inner surface of the first passage  9  and a top surface  7   a  of the thin portion  71  when the deformable portion  8  is deformed. 
     The second passage  10  is a passage through which the suture  2  passes into the space S from the one end side of the secured end  8   a , is formed on the one end side with respect to the free end  8   b  and the first passage  9 , and communicates the space S and the one end side of the secured end  8   a . The suture  2  passes through the second passage  10  once. The diameter of the second passage  10  is greater than the diameter of the suture  2  and the suture  2  in the second passage  10  is movable at least in the longitudinal direction of the base  7  with respect to the base  7 . 
     Specifically, as shown in  FIGS.  3 B to  4 B , the second passage (second hole)  10  is a hole that extends through the thick portion  72  of the base  7  in the longitudinal direction of the base  7  and that extends through one end portion of the thin portion  71  in the thickness direction. One of the openings of the second passage  10  is formed in a side surface  72   b  on the one end side of the thick portion  72  and the bottom surface  7   b  and is a large opening that is continuous between the side surface  72   b  and the bottom surface  7   b . The other opening of the second passage  10  is formed in the side surface  72   a  on the other end side of the thick portion  72  and the top surface  7   a  of the thin portion  71  and is an opening that is continuous between the side surface  72   a  and the top surface  7   a.    
       FIGS.  6 A to  6 E  describe a method for attaching the suture anchor  12  to the suture  2 . The anchors  11  and  12  are attached to the suture  2  by a manufacturer, and the laceration repair device  1  is provided to a user in a state in which the anchors  11  and  12  are loaded in the delivery device  3 . 
     In the case in which the laceration repair device  1  is provided to the user in a state in which the anchors  11  and  12 , the suture  2 , and the delivery device  3  are separated from each other, the user may attach the anchors  11  and  12  to the suture  2 . 
     As shown in  FIG.  6 A , the suture anchor  12  is attached to the suture  2  after attaching the first anchor  11  to the secured end portion  2   a  of the suture  2  by means of a publicly known method. As shown in  FIG.  6 B , the free end portion  2   b  of the suture  2  is made to pass through the first passage  9  from the lower side to the upper side and is moved to the one end side of the deformable portion  8  and the base  7  via the other end side and the upper side of the deformable portion  8 . 
     Next, as shown in  FIG.  6 C , the free end portion  2   b  is made to pass through the second passage  10  from the one end side to the other end side and is moved to the upper side of the deformable portion  8  via the space S and the other end side of the deformable portion  8 . At this time, one of the openings of the second passage  10 , which serves as the entrance for the suture  2 , is the large opening that is continuous between the side surface  72   a  and the bottom surface  7   b . Therefore, as respectively indicated by the solid line and the broken line in  FIG.  4 A , it is possible to easily make the suture  2  pass into the second passage  10  from the one end side or the lower side. 
     Next, as shown in  FIG.  6 D , the free end portion  2   b  is moved to the lower side of the deformable portion  8  from the upper side thereof via the other end side of the deformable portion  8  and is made to pass through the first passage  9  from the upper side to the lower side. Next, as shown in  FIG.  6 E , the free end portion  2   b  is pulled and the excess length of the suture  2  between the second passage  10  and the first passage  9  is eliminated. 
     As a result of making the free end portion  2   b  of the suture  2  pass through the passages  9  and  10  in the above-described manner, the suture  2  extends from the first passage  9  via the other end side, the upper side, and the one end side of the deformable portion  8  and subsequently returns to the first passage  9  via the second passage  10  and the space S. Therefore, two portions  21  and  22  of the suture  2  pass through the first passage  9 . The first portion  21  is a portion on the first anchor  11  side, extending along a first route P1 leading to the first anchor  11 , and extends toward the upper side of the deformable portion  8  from the first passage  9  via the other end side of the deformable portion  8 . The second portion  22  is a portion on the free end portion  2   b  side, extending along a second route P2 leading to the free end portion  2   b , and extends toward the one end side of the deformable portion  8  from the first passage  9  via the space S and the second passage  10 . 
     As shown in  FIG.  4 A , the suture  2  wound around the periphery of the deformable portion  8  in this way is movable with respect to the suture anchor  12  in accordance with a pulling force when the second portion  22  in the second route P2 is pulled. On the other hand, as shown in  FIG.  4 B , the suture  2  cannot be moved with respect to the suture anchor  12  due to the deformation of the deformable portion  8  when the first portion  21  in the first route P1 is pulled. 
     Thus, as shown in  FIG.  4 A , when the second portion  22  in the second route P2 is pulled, the suture  2  is pulled toward the upper side at the other end side of the deformable portion  8 . Therefore, a pressing force that causes the deformable portion  8  to be deformed toward the lower side is not applied to the deformable portion  8  from the suture  2  and the suture  2  is moved with respect to the base  7  and the deformable portion  8  in accordance with the pulling force. In other words, as a result of the free end portion  2   b  being pulled, the suture  2  is moved with respect to the second anchor  12  away from the first anchor  11 . As the suture  2  is moved with respect to the second anchor  12 , a portion of the suture  2  between the anchors  11  and  12  becomes shorter and shifts into a tensioned state from a relaxed state. 
     On the other hand, as indicated by the arrow in  FIG.  4 B , when the first portion  21  in the first route P1 is pulled, the suture  2  is pulled toward a lower side at the other end side of the deformable portion  8 . Therefore, the pressing force that causes the deformable portion  8  to be deformed toward the lower side is applied to the deformable portion  8  from the suture  2 , the other end portion of the deformable portion  8  is pressed toward the thin portion  71  of the base  7 , and the suture  2  is held between the thin portion  71  and the other end portion of the deformable portion  8 . The held suture  2  cannot be moved with respect to the suture anchor  12  regardless of the pulling force and is secured with respect to the suture anchor  12 . With an increase in the pulling force, the tensile force increases and the deformable portion  8  is pressed against the thin portion  71  with a greater force; therefore, the securing force with respect to the suture  2  increases. 
     Guide grooves  13  and  14  for preventing the suture  2  from being moved in transverse directions of the base  7  and the deformable portion  8  may be formed in the side surface  72   b  on the one end side of the base  7  and a side surface on the other end side of the deformable portion  8 . The guide groove  13  extends over the entire length of the base  7  in the thickness direction thereof at a center of the transverse direction of the base  7  and accommodates the suture  2  in the radial direction. The guide groove  14  extends over the entire length of the deformable portion  8  in the thickness direction thereof at a center of the transverse direction of the deformable portion  8  and accommodates the suture  2  in the radial direction. With this configuration, when a tensile force is applied to the suture  2 , the suture  2  is prevented from slipping along a surface of the base  7  or the deformable portion  8  in the transverse direction and falling off from the suture anchor  12 , and thus, it is possible to hold the suture  2  at an appropriate position with respect to the base  7  and the deformable portion  8 . 
     Next, a laceration repair method employing the laceration repair device  1  will be described with reference to  FIGS.  7 - 10 B . 
       FIGS.  8 - 10 B  show, as an example, a case of repairing a laceration B of a meniscus A of a knee joint. As shown in  FIG.  8   , the meniscus A is crescent shaped or C-shaped soft tissue disposed between a joint surface of a femur C and a joint surface of a tibia D, an outer edge of the meniscus A is connected to a joint capsule E encasing the knee joint. Reference sign F indicates a synovium.  FIGS.  8 - 9 F  show, as an example of the laceration B, a longitudinal fracture in which the meniscus A is torn in a longitudinal direction.  FIGS.  9 A- 9 F  are diagrams in which the meniscus A is viewed from the femur C side and the synovium F is omitted.  FIGS.  10 A and  10 B  are longitudinal sectional view of the meniscus A in the laceration B. 
     As shown in  FIG.  7   , the laceration repair method includes first step S1 to eighth step S8. 
     In first step S1, the first anchor  11  and the second anchor  12  are attached to the suture  2  by means of the above-described method. Next, in second step S2, the anchors  11  and  12  attached to the suture  2  are loaded into the needle  5  of the delivery device  3 . As described above, in the case in which the laceration repair device  1  is provided to the user in the state in which the anchors  11  and  12  are loaded to the delivery device  3 , the user does not need to perform steps S1 and S2. Therefore, steps S1 and S2 may be omitted. 
     Prior to third step S3, an arthroscope is inserted into the knee joint. As needed, a liquid is injected into the knee joint in order to expand the knee joint, and the size of the laceration B is measured. 
     Next, in third step S3, the delivery device  3  is inserted into the knee joint. 
     Next, in fourth step S4, the first anchor  11  is disposed at the joint capsule (tissue) E. Specifically, as shown in  FIG.  9 A , the meniscus A is pierced with the needle  5  radially outside the laceration B and the needle  5  is made to pass through the meniscus A until the needle tip  5   a  protrudes from an outer surface of the joint capsule E. Next, the first anchor  11  is pushed out from the needle tip  5   a  and the first anchor  11  is disposed on the outer surface of the joint capsule E. Next, as shown in  FIG.  9 B , the delivery device  3  is pulled toward the proximal side and the needle  5  is removed from the meniscus A. 
     Next, in fifth step S5, the second anchor  12  is disposed at the joint capsule E. Specifically, as shown in  FIG.  9 C , the meniscus A is pierced with the needle  5  on radially inside the laceration B and the needle  5  is made to pass through the meniscus A, crossing the laceration B, until the needle tip  5   a  protrudes from the outer surface of the joint capsule E. Next, the second anchor  12  is pushed out from the needle tip  5   a , and the second anchor  12  is disposed on the outer surface of the joint capsule E. Next, as shown in  FIG.  9 D , the delivery device  3  is pulled toward the proximal side, and the needle  5  is removed from the meniscus A. 
     As a result of performing fourth step S4 and fifth step S5, as shown in  FIG.  10 A , the portion of the suture  2  between the first anchor  11  and the second anchor  12  crosses the laceration B on a surface As of the meniscus A. 
     Next, in sixth step S6, as indicated by the arrow in  FIG.  10 A , the free end portion  2   b  of the suture  2  is pulled. As the free end portion  2   b  is pulled, the portion of the suture  2  between the first anchor  11  and the second anchor  12  gradually becomes shorter and the laceration B is closed, as shown in  FIGS.  9 E and  10 B . 
     Next, in seventh step S7, as shown in  FIG.  9 F , the suture  2  is cut by using an arbitrary instrument inserted into the knee joint. The arrow in  FIG.  10 B  indicates the position at which the suture  2  is cut. As shown in  FIG.  10 B , after cutting the suture  2 , only the thin, flexible suture  2  remains on the surface As on the femur C side of the meniscus A. 
     Next, in eighth step S8, the delivery device  3  is pulled toward the proximal side and the delivery device  3  is removed from the knee joint. 
     After the laceration B is closed as a result of pulling the free end portion  2   b , there are cases in which the suture  2  is pulled in the direction in which the laceration B opens, in other words, there are cases in which the first portion  21  in the first route P1 is pulled. With the suture anchor  12  of this embodiment, when the suture  2  is pulled in the direction in which the laceration B opens, the suture  2  is secured with respect to the suture anchor  12  by the deformable portion  8  being deformed due to the tensile force of the suture  2  and the movement of the suture  2  in the direction in which the laceration B opens is prevented. Specifically, after closing the laceration B once by pulling the free end portion  2   b , loosening of the suture  2  is prevented by the deformable portion  8  and the tensile force of the suture  2  between the first anchor  11  and the second anchor  12  is maintained. Therefore, although a structure, such as a slip knot, for preventing loosening of the suture  2  has conventionally been necessary at the position indicated by the broken-line circle in  FIG.  10 B , such a structure is not required in this embodiment. Accordingly, it is possible to complete suturing without leaving a protruding object, such as a knot, for preventing loosening of the suture  2  on the surface As of soft tissue A after suturing. In the case in which the soft tissue A is a meniscus, because a protruding object does not remain on the femur C-side surface As, which is a sliding surface of the knee joint, it is possible to prevent an influence on sliding of the joint. 
     In addition, because a knot that has conventionally been necessary is not required, there is an advantage in that it is possible to simplify the procedures.  FIG.  17    shows a comparative example of the laceration repair method according to this embodiment, which is a laceration repair method for the case in which a slip knot is formed in the suture  2 . 
     In the comparative example, step S2′ for forming a knot in the suture  2  after attaching the suture  2  to two conventional anchors is necessary. In addition, step S7′ for moving the knot to a surface of the soft tissue by pulling the suture  2  after disposing the second anchor is necessary. In this case, the knot is disposed at the position indicated by the broken-line circle in  FIG.  10 B . In this embodiment, these steps S2′ and S7′ are not required. 
     In the case in which the rigidity of the base  7  is low, not only the deformable portion  8  but also the base  7  could be deformed due to the tensile force of the suture  2 . In order to prevent the deformation of the base  7 , the base  7  may have a greater rigidity as compared with the deformable portion  8 . 
       FIGS.  11 A and  11 B  show an example of the suture anchor  12  in which the rigidity of the base  7  is enhanced. In  FIG.  11 A , the thickness of the base  7  is increased and the thin portion  71  has a greater thickness than the deformable portion  8 . In  FIG.  11 B , a high-rigidity material  15  is incorporated into the base  7  by means of integral molding. The high-rigidity material  15  is formed from, for example, a meatal such as a titanium alloy. 
     In this embodiment, a structure for increasing the securing force with respect to the suture  2  may be provided in at least one of the base  7  and the deformable portion  8 .  FIGS.  12 - 15    show examples of the structure for increasing the securing force. 
     Two or more of a friction increasing treatment  16  in  FIG.  12   , a groove  17  in  FIGS.  13 A- 14 B , and protrusions  18  in FIG.  15  may be provided in the suture anchor  12 . 
     In  FIG.  12   , the friction increasing treatment  16  is applied to a bottom surface  8   c  of the deformable portion  8 . One example of the friction increasing treatment  16  is a treatment for forming a rough surface in the bottom surface  8   c  by forming a plurality of depressions or a plurality of protrusions on the bottom surface  8   c . The deformed deformable portion  8  is in firm contact with the suture  2  at the other end portion. Therefore, it is most effective to apply the friction increasing treatment  16  to the bottom surface  8   c  at the other end portion of the deformable portion  8 . Due to the friction increasing treatment  16 , it is possible to increase the frictional force between the bottom surface  8   c  of the deformed deformable portion  8  and the suture  2 . 
     In  FIGS.  13 A- 13 C , the groove  17  is formed in an inner surface of the first passage  9 . The groove  17  is formed in a region on the one end side in the inner surface of the first passage  9  and extends toward the bottom surface  7   b  from the top surface  7   a . It is preferable that at least a portion of the groove  17  have a diameter that is smaller than the diameter of the suture  2 . In the illustrated example, the groove  17  has a V-shape in which the width thereof gradually decreases toward the one end side. 
     When an additional tensile force is applied to the suture  2  in the state in which the deformed deformable portion  8  is holding down the suture  2  in the second route P2, the two portions of the suture  2  in the first passage  9  enter the groove  17  and friction is generated between an inner surface of the groove  17  and the suture  2 . Due to this friction, the securing force with respect to the suture  2  increases. 
     As shown in  FIGS.  14 A and  14 B , the first passage  9  may have two holes  91  and  92  that are arrayed in the longitudinal direction of the base  7 , and the groove  17  may be formed in an inner surface of the hole  91  on the other end side. The first portion  21  in the first route P1 passes through the hole  91 , and the second portion  22  in the second route P2 passes through the hole  92  on the one end side. 
     With this configuration, when the first portion  21  is pulled, the second portion  22  passing through the hole  92  is secured by being held between the thin portion  71  and the deformed deformable portion  8 , and the first portion  21  passing through the hole  91  is secured by getting into the groove  17 . 
     In  FIG.  15   , the bottom surface  8   c  of the deformable portion  8  is provided with one or more protrusions  18  that protrude toward the lower side. As with the friction increasing treatment  16 , it is preferable that the protrusions  18  be provided on the bottom surface  8   c  of the other end portion of the deformable portion  8 . As a result of the protrusions  18  being pressed against the suture  2  when the deformable portion  8  is deformed, the securing force with respect to the suture  2  increases. 
     In the above-described embodiment, the orientations and the positions of the first passage  9  and the second passage  10  may be changed, so long as it is possible to wind the suture  2  around the deformable portion  8  so that the suture  2  extends from the first passage  9  and returns to the first passage  9  via the other end side, the upper side, and the one end side of the deformable portion  8 , the second passage  10 , and the space S. 
     For example, the entire first passage  9  may be formed on the one end side with respect to the free end  8   b . The second passage  10  may extend through only the thick portion  72  in the longitudinal direction of the base  7 , as shown in  FIGS.  11 A- 15   , or the second passage  10  may extend through only the thin portion  71  of the base  7  in the thickness direction. Alternatively, the second passage  10  may be an L-shaped passage that extends through the thick portion  72  from the side surface  72   a  to the top surface  7   a.    
       FIGS.  16 A- 16 C  show a modification of the suture anchor  12 . In the suture anchor  12  in  FIGS.  16 A- 16 C , the second passage  10  is a hole that extends through the thick portion  72  of the base  7  in the thickness direction and that opens in the top surface  7   a  and the bottom surface  7   b  of the thick portion  72  and opens into the space S. It is preferable that the second passage  10  also extend through the one end portion of the thin portion  71  in the thickness direction and form a large opening in the bottom surface  7   b  so that it is possible to make the suture  2  easily pass into the second passage  10  from the lower side. With such a second passage  10  also, it is possible to guide the suture  2  to the space S from the one end side of the secured end  8   a . In addition, it is possible to reliably prevent the suture  2  from falling off from the base  7 . 
     In this embodiment, the base  7  has the thin portion  71  and the thick portion  72  and the deformable portion  8  is disposed so as to be parallel to the thin portion  71 ; however, so long as the secured end  8   a  is secured to the base  7  and the free end  8   b  is disposed so as to be separated by the space S from the base  7 , it is possible to change the shape of the base  7  and the arrangement of the deformable portion  8  with respect to the base  7 . For example, the base  7  may be a flat plate having the flat top surface  7   a  and bottom surface  7   b  and the deformable portion  8  may be inclined upward toward the free end  8   b  from the secured end  8   a  with respect to the base  7 . 
     Although this embodiment has been described in terms of a case in which the suture anchor  12  and the laceration repair device  1  are used to repair a laceration of a meniscus, tissue to which the suture anchor  12  and the laceration repair device  1  are applied is not limited to a meniscus and may be other soft tissue, such as a muscle, a ligament, and cartilage. 
     In a conventional art, a slip knot that prevents the movement of the suture in the direction in which the wound opens is necessary in order to prevent the wound from opening as a result of the suture becoming loosened after closing the wound. Therefore, time and effort are required to form the knot. In addition, after repairing the wound, the knot remains on the tissue surface as a protruding object. In the case in which the tissue is a meniscus, the knot is disposed on a sliding surface of the joint; therefore, the knot may affect sliding of the joint. 
     The following aspects have been conceived in light of the above-described circumstances, and an object thereof is to provide a suture anchor and a device that are capable of preventing loosening of a suture without having to leave a protruding object such as a knot on a tissue surface. 
     An aspect of the present invention is a suture anchor including: a plate-like base that has an upper side and a lower side in a thickness direction of the base and that has one end and the other end in a direction intersecting the thickness direction; a deformable portion disposed at an upper side of the base, at least a side of the other end of the deformable portion being disposed so as to be separated by a space from the base; and a first passage and a second passage each formed in the base to allow a suture to pass therethrough, wherein the deformable portion is a cantilever state having a fixed end, which is disposed at a side of the one end and fixed to the base, and a free end, which is disposed at a side of the other end, and the deformable portion is deformable in a direction in which the free end approaches the base, the first passage communicates the upper side and the lower side of the base, the second passage is formed on a side of the one end relative to the free end and the first passage and communicates the space and a side of the one end of the fixed end, and the deformable portion is deformed due to a tensile force applied to the suture, which extends from the first passage and returns to the first passage via a side of the other end relative to the deformable portion, an opposite side of the deformable portion when seen from the base, a side of the one end relative to the deformable portion, the second passage, and the space, and to hold the suture between the deformable portion and the base. 
     The suture anchor of this aspect is attached to the suture by winding the suture to surround the deformable portion by making the suture sequentially pass through the first passage, the second passage, and the first passage. Specifically, the suture passes through the first passage from the lower side of the base to the upper side, passes through the second passage from the side of the one end of the deformable portion to the space via the side of the other end of the deformable portion, the side of the deformable portion opposite to the base, and side of the one end of the deformable portion, and passes through the first passage from the upper side of the base to the lower side. As a result of a tensile force being applied to the suture that is wound around the deformable portion in the above-described way, the cantilever sate deformable portion is deformed in the direction in which the free end approaches the base, the suture disposed in the space is held between the base and the deformed deformable portion, and thus, the suture is secured with respect to the suture anchor. 
     As described above, with the suture anchor of this aspect, the suture anchor itself applies the securing force with respect to the suture due to the tensile force of the suture; therefore, a protruding object, such as a knot, for preventing unintentional movement of the suture with respect to the suture anchor is not required. Accordingly, it is possible to prevent loosening of the suture without having to leave a protruding object on a tissue surface. 
     In the above-described aspect, the first passage may have a first hole that extends through the base, and the second passage may have a second hole that extends through the base. The base may have a thin portion that faces the deformable portion in the thickness direction and a thick portion that is provided on the one end side of the thin portion, and the second hole may extend through the thick portion in a longitudinal direction of the base. 
     With this configuration, it is possible to provide the first passage and the second passage by means of simple processing for simply forming the holes extending through the base, and thus, it is possible to simplify the configuration of the base. 
     In the above-described aspect, the first hole may be formed on a side of the other end with respect to the free end, and the second hole may be formed on a side of the one end with respect to the free end. 
     As a result of forming the first hole on the side of the other end with respect to the free end, it is possible to make the suture easily pass through the first hole without being interfered by the deformable portion. In addition, as a result of forming the first hole and the second hole on either side of the free end, it is possible to hold a portion of the suture extending from the second hole to the first hole between the deformed deformable portion and the base. 
     In the above-described aspect, a friction increasing treatment may be applied to a bottom surface of a base side of the deformable portion. 
     When the deformable portion is deformed, the bottom surface of the deformable portion comes into contact with the suture. The friction between the deformed deformable portion and the suture increases due to the friction increasing treatment on the surface of the deformable portion, and thus, it is possible to increase the securing force with respect to the suture. 
     In the above-described aspect, a groove that extends in the thickness direction may be provided in a region on a side of the one end in an inner surface of the first hole. 
     With this configuration, when a tensile force is applied to the suture, the suture in the first hole is pulled toward the side of the one end and gets into the groove, and thus, friction is generated between the suture and an inner surface of the groove. Accordingly, it is possible to increase the securing force with respect to the suture. 
     In the above-described aspect, a protrusion may be provided in a bottom surface of a base side of the deformable portion. 
     With this configuration, as a result of the protrusion being pressed against the suture when the deformable portion is deformed, it is possible to increase the securing force with respect to the suture. 
     Another aspect of the present invention is a laceration repair device including: a suture; a first anchor attached to the suture; any one of the suture anchors described above, which serves as a second anchor attached to the suture, and a delivery device that has a hollow needle and that is capable of loading the first anchor and the second anchor in an interior of the needle, wherein the suture is attached to the second anchor so as to be movable relative to the second anchor in a direction away from the first anchor. 
     In the above-described another aspect, as a result of pulling a portion of the suture on the first anchor side, which extends toward the first anchor from the second anchor, a tensile force may be generated in the suture and the deformable portion may be deformed. 
     In the above-described other aspect, the second anchor may be attached to the suture at a position between a free-end portion of the suture and the first anchor, and, a portion of two portions of the suture that pass through the first passage, which is one at a side of the first anchor, extends from the first passage to the opposite side of the deformable portion when seen from the base via the side of the other end of the deformable portion. 
     With this configuration, when a pulling force toward the first anchor side acts on a portion of the suture extending from the second anchor to the first anchor, a tensile force is generated in the suture, the suture is held by the deformed deformable portion, and the movement of the suture with respect to the second anchor is prevented. Thus, it is possible to prevent the suture from moving with respect to the second anchor in a direction in which the length of the portion of the suture between the second anchor and the first anchor increases. 
     The above aspects afford an advantage in that it is possible to prevent loosening of a suture without having to leave a protruding object such as a knot on a tissue surface. 
     REFERENCE SIGNS LIST 
     
         
           1  laceration repair device 
           11  first anchor 
           12  second anchor, suture anchor 
           2  suture 
           3  delivery device 
           5  needle 
           5   a  needle tip 
           7  base 
           7   a  top surface 
           7   b  bottom surface 
           8  deformable portion 
           8   a  secured end 
           8   b  free end 
           8   c  bottom surface 
           9  first passage, first hole 
           10  second passage, second hole 
           16  friction increasing treatment 
           17  groove 
           18  protrusion