Patent Publication Number: US-2013245686-A1

Title: Compact line locks and methods

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of: 
     U.S. application Ser. No. 13/758,171, filed Feb. 4, 2013, which carries Applicants&#39; docket no. MLI-32 CON2, and is entitled COMPACT LINE LOCKS AND METHODS. 
     U.S. patent application Ser. No. 13/758,171 is a continuation of: 
     U.S. application Ser. No. 12/754,774, filed Apr. 6, 2010, which carries Applicants&#39; docket no. MLI-32 CON, and is entitled COMPACT LINE LOCKS AND METHODS. 
     U.S. patent application Ser. No. 12/754,774 is a continuation of: 
     U.S. application Ser. No. 11/125,885, now U.S. Pat. No. 7,722,644, filed May 9, 2005, which carries Applicants&#39; docket no. MLI-32, and is entitled COMPACT LINE LOCKS AND METHODS. 
     U.S. patent application Ser. No. 11/125,885 is a continuation-in-part of the following: 
     U.S. application Ser. No. 10/459,375, now U.S. Pat. No. 7,150,757, filed Jun. 11, 2003, which carries Applicants&#39; docket no. 13447.35, and is entitled LINE LOCK SUTURE ATTACHMENT SYSTEMS AND METHODS; 
     U.S. application Ser. No. 10/936,376, now U.S. Pat. No. 7,566,339, filed Sep. 7, 2004, which carries Applicants&#39; docket no. MLI-15 and is entitled ADJUSTABLE LINE LOCKS AND METHODS; 
     U.S. application Ser. No. 10/942,275, now U.S. Pat. No. 7,806,909, filed Sep. 15, 2004, which carries Applicants&#39; docket no. MLI-16 and is entitled LINE LOCK THREADING SYSTEMS AND METHODS; and 
     U.S. application Ser. No. 11/001,866, now U.S. Pat. No. 7,594,923, filed Dec. 1, 2004, which carries Applicants&#39; docket no. MLI-17 and is entitled LINE LOCK SUTURE ATTACHMENT SYSTEMS AND METHODS. 
     All of the above-named documents are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. The Field of the Invention 
     The present invention relates generally to devices to replace knots and more specifically to devices to replace surgical knots tied in open, arthroscopic, and endoscopic procedures. 
     2. The Relevant Technology 
     Numerous devices have been developed to eliminate the need to tie knots as a way of securing a line. The devices that accomplish the same function as a knot, which is in part to secure a line to retain tension in a portion of the line, are typically referred to as line locks. 
     Line locks generally operate in one of two ways. Some line locks are manually actuated to secure one or more lines so that tension is maintained in a portion of the line(s). Once actuated, the line lock resists sliding along the line(s) either toward or away from the tensioned portion of the line. Other line locks are continuously adjustable in one direction so that tension is increased in the portion of the line upon which the line lock is advanced. The continuously adjustable line locks resist movement away from the tensioned portion of the line, but can be further advanced toward the tensioned portion of the line with an appropriately applied force. 
     The portion of a line that is put under tension, typically to secure some object, is commonly referred to as the standing end. The portion of the line that extends toward the line handler is commonly referred to as the working end. A knot in a line, or a line lock attached to a line, is the demarcation between the standing end and the working end. 
     Continuously adjustable line locks offer several advantages. They are passive locking devices, meaning that no other operation is required to secure the line lock once it is moved along the line to its desired position. Furthermore, these line locks can be used to continuously increase the tension in the standing end until it reaches a desired level of tension. 
     The advantages of line locks over tied knots are very attractive in many varied applications, including the use of surgical sutures. However, the line locks developed to date have many deficiencies when considered for surgical suture applications. 
     Many known line locks for surgical applications are somewhat small, and as a result, they have small passageways that are positioned quite close to each other. This makes it somewhat difficult to thread the suture through the line lock in the proper pattern. Furthermore, the user must select and apply the correct suture because improper suture selection can impair the locking and/or strength of the attachment system. Additionally, the proper needle must be attached to the suture. Thus, there are multiple selection and assembly steps that must be performed prior to use of the attachment system. 
     Known line locks use line on line friction to create the locking effect, and this line on line friction makes it difficult to advance the line lock over suture. Known line locks rely on maintenance of tension in the standing end to prevent the line lock from migrating back along the working end. 
     In surgical suture applications, the working end is typically trimmed closely to the line lock. As a result, the line lock can easily disassociate from the suture once tension in the standing end is lost. In most, if not all, surgical applications, a free-floating device such as a line lock can potentially harm adjacent body tissues. Additionally, known line locks are susceptible to loosening during cyclic variations in the tension of the standing end. This cyclic variation in the standing end tension is common in surgical applications as tissues are stressed and then relaxed. Loosening of the line lock thus compromises the securing function for which it was intended. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. 
         FIG. 1  is a perspective view of an adjustable line lock. 
         FIG. 2  is a top plan view of line lock shown in  FIG. 1 . 
         FIG. 3  is an elevated cross sectional side view of the line lock shown in  FIG. 1 . 
         FIG. 4A  is a perspective view of the line lock shown in  FIG. 1  with a line routed therethrough in a slack unlocked position. 
         FIG. 4B  is a perspective view of the line lock shown in  FIG. 4A  with the line in a tensioned locked position. 
         FIG. 5  is a top plan view of the line lock shown in  FIG. 4B . 
         FIG. 6  is a bottom cross sectional view of the line lock shown in  FIG. 4B . 
         FIG. 7  is a perspective view of the line lock shown in  FIG. 1  with a line routed in a different path. 
         FIG. 8  is a perspective view of an alternative embodiment of the line lock shown in  FIG. 1  with open working passageways. 
         FIG. 9  is a perspective view of another alternative embodiment of the line lock shown  FIG. 1  with open passageways. 
         FIG. 10  is a perspective view of another alternative embodiment of the line lock shown in  FIG. 1  with dual primary passageways and uniform working passageways. 
         FIG. 11  is a perspective view of a line lock for use with a single strand of line. 
         FIG. 12A  is a perspective view of the line lock shown in  FIG. 11  with a line routed therethrough. 
         FIG. 12B  is a top plan view of the line lock shown in  FIG. 12A . 
         FIG. 12C  is a bottom plan view of the line lock shown in  FIG. 12A . 
         FIG. 13A  is a top perspective view of a line lock having dual strands of line routed therethrough. 
         FIG. 13B  is a bottom perspective view of the line lock shown in  FIG. 13A . 
         FIG. 14A  is a top perspective view of a line lock having a line secured thereto. 
         FIG. 14B  is a bottom perspective view of the line lock shown in  FIG. 14A . 
         FIG. 15  is a perspective view of an alternative embodiment of a line lock. 
         FIG. 16A  is a perspective view of the line lock shown in  FIG. 15  with a line routed therethrough. 
         FIG. 16B  is a top plan view of the line lock shown in  FIG. 16A . 
         FIG. 16C  is a bottom plan view of the line lock shown in  FIG. 16A . 
         FIG. 17  is a perspective view of another alternative embodiment of a line lock. 
         FIG. 18A  is a perspective view of the line lock shown in  FIG. 17  with a line routed therethrough. 
         FIG. 18B  is a top plan view of the line lock shown in  FIG. 18A . 
         FIG. 18C  is a bottom plan view of the line lock shown in  FIG. 18A . 
         FIG. 19  is a perspective view of a line lock according to another alternative embodiment of the invention, with an associated insertion tool. 
         FIG. 20  is a perspective view of the line lock of  FIG. 19 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 21  is a perspective view of the line lock of  FIG. 19 , with the suture passing tightly through the passageways of the line lock. 
         FIG. 22  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 23  is a perspective view of the line lock of  FIG. 22 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 24  is a perspective view of the line lock of  FIG. 22 , with the suture passing tightly through the passageways of the line lock. 
         FIG. 25  is a perspective view of a line lock according to yet another alternative embodiment of the invention. 
         FIG. 26  is a perspective view of the line lock of  FIG. 25 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 27  is a perspective view of the line lock of  FIG. 25 , with the suture passing tightly through the passageways of the line lock. 
         FIG. 28  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 29  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 30  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 31  is a perspective view of the line lock of  FIG. 30 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 32  is a perspective view of the line lock of  FIG. 30 , with suture passing tightly through the passageways of the line lock. 
         FIG. 33  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 34  is a perspective view of the line lock of  FIG. 33 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 35  is a perspective view of the line lock of  FIG. 33 , with suture passing tightly through the passageways of the line lock. 
         FIG. 36  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 37  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 38  is a perspective view of the line lock of  FIG. 37 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 39  is a perspective view of the line lock of  FIG. 37  with suture passing tightly through the passageways of the line lock. 
         FIG. 40  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 41  is a perspective view of the line lock of  FIG. 40 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 42  is a perspective view of the line lock of  FIG. 40  with suture passing tightly through the passageways of the line lock. 
         FIG. 43  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 44  is a perspective view of the line lock of  FIG. 43 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 45  is a perspective view of the line lock of  FIG. 43  with suture passing tightly through the passageways of the line lock. 
         FIG. 46  is a perspective view of a line lock according to another alternative embodiment of the invention. 
         FIG. 47  is a perspective view of the line lock of  FIG. 46 , with a suture passing loosely through the passageways of the line lock. 
         FIG. 48  is a perspective view of the line lock of  FIG. 46  with suture passing tightly through the passageways of the line lock. 
         FIG. 49  is a perspective view of a system including a cartridge with threaders that facilitate the insertion of suture through the passageways of the line lock of  FIG. 19 . 
         FIG. 50  is a perspective view of the system of  FIG. 49 , with the lid of the cartridge open and sutures coupled to the trailing ends of the threaders. 
         FIG. 51  is a perspective view of the system of  FIG. 49 , with the cartridge open and one of the sutures drawn part-way through the cartridge. 
         FIG. 52  is a perspective view of the system of  FIG. 49 , with the cartridge open and the sutures fully drawn through the cartridge to pass through the passageways of the line lock. 
         FIG. 53  is a perspective view of the system of  FIG. 49 , the cartridge open and the sutures and line removed from the cartridge for use. 
         FIG. 54  is a perspective view of a line lock according to another embodiment of the invention. 
         FIG. 55  is a perspective view of the line lock of  FIG. 54 , with a suture threaded loosely therethrough 
         FIG. 56  is a perspective view of the line lock of  FIG. 54 , with a suture threaded tightly therethrough. 
         FIG. 57  is a perspective view of a line lock according to yet another embodiment of the invention. 
         FIG. 58  is a perspective view of the line lock of  FIG. 57 , with the suture threaded loosely therethrough. 
         FIG. 59  is a perspective view of the line lock of  FIG. 57 , with the suture threaded tightly therethrough. 
         FIG. 60  is a perspective view of a system including a cartridge with a threader that facilitates the insertion of the pre-attached suture through the passageways of the line lock of  FIGS. 14A and 14B . 
         FIG. 61  is a perspective view of the system of  FIG. 60 , with the lid of the cartridge open and the suture coupled to the trailing end of the threader. 
         FIG. 62  is a perspective view of the system of  FIG. 60 , with the cartridge open and the suture drawn part-way through the cartridge. 
         FIG. 63  is a perspective view of the system of  FIG. 60 , with the cartridge open and the suture fully drawn through the cartridge to pass through the passageways of the line lock. 
         FIG. 64  is a perspective view of the system of  FIG. 60 , with the cartridge open and the suture and line lock removed from the cartridge for use. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention relates to line locks that can be used in part to replace surgical knots tied in sutures in open, arthroscopic, and endoscopic procedures. By increasing the size of the line locks, it is also appreciated that the line locks can be used outside of surgical procedures for any use where it is desired to selectively adjust and/or tie off a line such as a rope, cord, string, or other conventional type of line. 
     In this application, the term “couple” broadly refers to connection of two items to each other. Two items may be “coupled” if they are connected together in a manner that prevents relative motion on one direction, but not another. A “longitudinal length” of an object is the length of the object along its longest dimension. “Cooperation” of a plurality of passageways to receive multiple suture portions does not require that each suture portion pass through all of the cooperating passageways. 
     Depicted in  FIG. 1  is one embodiment of a line lock  10  incorporating features of the present invention. Line lock  10  comprises an elongated body  12  having a top surface  14  and an opposing bottom surface  16  that each extend between a first end  18  and an opposing second end  20 . Body  12  also has a first side  19  and an opposing second side  21  extending between first end  18  and second end  20 . In the embodiment depicted, body  12  has a substantially rectangular configuration with rounded ends. As will be apparent from the following disclosure, however, body  12  can be any desired configuration such as triangular, circular, square or any other polygonal or irregular configuration. 
     In typical surgical applications, body  12  has a maximum dimension D along its length ( FIG. 2 ) which is typically less than about 2 cm, more commonly less than about 1.5 cm, and even more commonly less than about 1 cm. Other dimensions can also be used. By way of example and not by limitation, in one embodiment body  12  has a height in a range between about 1 mm to about 1.5 mm, a width in a range between about 2 mm to about 3 mm, and length D in a range between about 5 mm to about 8 mm. In non-surgical applications, body  12  can be any desired dimension. For example, maximum dimension D can be in a range from about 5 cm to about 0.5 m. Again, other dimensions can also be used. 
     For use in surgical applications, body  12  can be comprised of any biocompatible material. The biocompatible material can be bioabsorbable or non-bioabsorbable. Examples of typical materials include non-bioabsorbable plastic, bioabsorbable plastic, synthetic tissue, and allograft tissue. In non-surgical applications, body  12  can be made of any desired material such as metal, plastic, wood, fiberglass, composite, or the like. 
     As depicted in  FIG. 1 , centrally extending through body  10  between top surface  14  and bottom surface  16  is a primary passageway  22 . As used in the specification and appended claims, the term “passageway” is broadly intended to include closed apertures, such as depicted by primary passageway  22 , partially bounded apertures, open channels, recesses, grooves, slots, and the like, that are capable of receiving a line and at least partially retaining the line therein. The term “line” as used in the specification and appended claims is broadly intended to include suture, cord, rope, filament, wire, cable, and any other form of line. 
     In this application, the phrase “substantially bounded aperture” refers to an aperture that is sufficiently encircled by material to prevent a line from exiting the aperture via motion transverse to the length or axis of the aperture. Thus, a substantially bounded aperture may be fully encircled by material, or may have one or more breaks, each of which is smaller than the diameter of the line that is to pass through the substantially bounded aperture. 
     Extending between surfaces  14  and  16  at first end  18  of body  12  is a first secondary passageway  24 . A second secondary passageway  24 ′ extends between surfaces  14  and  16  at second end  20 . Extending through body  12  at a location between primary passageway  22  and first secondary passageway  24  is a first working passageway  28 . In one embodiment, although not necessarily required, first working passageway  28  is disposed between primary passageway  22  and first secondary passageway  24  such that a geometric line segment  36  ( FIG. 2 ) can be extended between primary passageway  22  and first secondary passageway  24  so that line segment  36  intersects with first working passageway  28 . Similar to first working passageway  28 , a second working passageway  28 ′ extends through body  12  at a location between primary passageway  22  and second secondary passageway  24 ′. 
     Each working passageway  28  and  28 ′ has an elongated transverse cross sectional area that extends between a first end  38  and an opposing second end  40 . Each working passageway  28 ,  28 ′ comprises an enlarged access region  32  at first end  38  which communicates with a constricted capture slot  34  at second end  40 . Access region  32  is sized to enable easy feeding of a line into and through the corresponding working passageways  28 ,  28 ′. Accordingly, although access region  32  can be slightly smaller than the transverse cross sectional area of the line which is to be passed therethrough, access region  32  typically has a transverse cross sectional area that is equal to or slightly larger than the transverse cross sectional area of the line that is to be passed therethrough. 
     In contrast, capture slot  34  has a width W that is substantially equal to or less than the diameter of the line that is to be passed through working passageways  28 ,  28 ′. For example, in one embodiment width W is less than about 0.9 times the diameter of the line and more commonly less than about 0.75 times the diameter of the line. It is appreciated that working passageways  28 ,  28 ′ can come in a variety of different configurations. For example, capture slot  34  can come in a variety of different constricted, tapered, or notched shaped configurations that are capable of securely retaining a line through wedged engagement. For line made of less compressible material, such as metal, the required difference between the width W and the diameter of the line may be less than the examples given above. 
     As depicted in  FIG. 2 , central passageway  22  is bounded by an interior surface  42  of body  12  having a substantially triangular transverse cross section. Interior surface  42  comprises a first side face  44  disposed toward first working passageway  28 , a second side face  46  disposed toward second working passageway  28 ′ and which intersects with first side face  44 , and a third side face  48  extending between first side face  44  and second side face  46 . Although side faces  44  and  46  are shown as being substantially flat, in alternative embodiments side faces  44  and  46  can be curved or irregular. In one embodiment, however, first side face  44  is substantially disposed in or tangent to a first plane illustrated by dashed line  50 . With reference to  FIG. 2 , plane  50  slopes toward second end  40  of first working passageway  28  as plane  50  extends from first side  19  of body  12  to second side  21 . 
     First secondary passageway  24  is bounded by an interior surface  54  of body  12  having an elongated transverse cross section. Interior surface  54  comprises a first side face  56  disposed toward first working passageway  28  and an opposing second side face  58 . Although side faces  56  and  58  are shown as being substantially flat, in alternative embodiments side faces  56  and  58  can also be curved or irregular. Again, in one embodiment first side face  56  is substantially disposed in or tangent to a second plane illustrated by dashed line  60 . With reference to  FIG. 2 , second plane  60  slopes toward second end  40  of first working passageway  28  as second plane  60  extends from first side  19  of body  12  to second side  21 . 
     In the above discussed configuration, first plane  50  and second plane  60  are disposed so as to be converging as they extend from first side  19  of body  12  to second side  21 . In the embodiment depicted, planes  50  and  60  intersect at a location  62  on body  12  that is at least substantially aligned with a central longitudinal axis of capture slot  34 . In other embodiments, location  62  can be directly adjacent to body  12  or at a distance from body  12 . Likewise, location  62  need not be aligned with the central longitudinal axis of capture slot  34 . Although not required, in one embodiment planes  50  and  60  are disposed at equally opposing angles relative to the central longitudinal axis of capture slot  34 . Furthermore, planes  50  and  60  can intersect so as to form an inside angle therebetween in a range between about 5° to about 85°. 
     Second secondary passageway  24 ′ has substantially the same configuration as first secondary passageway  24 . Likewise, second secondary passageway  24 ′ has substantially the same relative position to second working passageway  28 ′ and second side face  46  of primary passageway  22  as first secondary passageway  26  has to first working passageway  28  and first side face  44  of primary passageway  22 . As such, the discussion with regard to planes  50  and  60  are also applicable to primary passageway  22  and second secondary passageway  24 ′. 
     By way of example of the passageways and not by limitation, for use with a size USP #2 braided suture, which has a diameter in a range between about 0.5 mm to about 0.6 mm, primary passageway  22  has a length in a range between about 1.3 mm to about 1.5 mm and a width in a range between about 1 mm to about 1.3 mm. Secondary passageways  24  and  24 ′ have a width of about 0.8 mm and a length in a range between 1 mm to about 1.3 mm. Access region  32  of working passageways  28  and  28 ′ have width in a range between about 0.7 mm to 1 mm while capture slots  17  have a width in a range between about 0.3 mm to 0.4 mm. 
     Depicted in  FIG. 3 , interior surface  42  of primary passageway  22  extends to a top outside corner  66  and an opposing bottom outside corner  68 . Top outside corner  66  bounds a top primary opening  70  while bottom outside corner  66  bounds a bottom primary opening  72 . Similarly, first working passageway  28  has an interior surface  74  that extends to a top outside corner  76  and an opposing bottom outside corner  78 . Top outside corner  76  bounds a top working opening  80  while bottom outside corner  76  bounds a bottom working opening  82 . Likewise, interior surface  54  of first secondary passageway  24  extends to a top outside corner  86  and an opposing bottom outside corner  88 . Top outside corner  86  bounds a top secondary opening  90  while bottom outside corner  86  bounds a bottom secondary opening  92 . 
     For reasons as will be discussed below in greater detail, each of top outside corners  66 ,  76 , and  86  has a radius of curvature that is smaller than the radius of curvature of the corresponding bottom outside corners  68 ,  78 ,  88 . By way of example and not by limitation, in one embodiment top outside corners  66 ,  76 , and  86  each have a radius of curvature in a range between about 0 mm to about 1 mm with about 0 mm to about 0.5 mm being more common. In contrast, bottom outside corners  68 ,  78 , and  88  each have a radius of curvature in a range between about 0.25 mm to about 2 mm with about 0.5 mm to about 1.5 mm being more common. Other dimensions can also be used, particularly outside of the surgical area. In yet other embodiments it is appreciated that the top outside corners and the bottom outside corners can have the same radius of curvature or that only one or more of the top outside corners may be smaller than one or more of the bottom outside corners. In still other embodiments, it is appreciated that only a portion of one or more of the top outside corners may be smaller than a portion of one or more of the bottom outside corners. 
     It is again noted that second secondary passageway  24 ′ and second working passageway  28 ′ having substantially the same configuration as first secondary passageway  24  and first working passageway  28 , respectively. As such, the same discussion with regard to the outside corners are also applicable thereto. Likewise, like elements are identified by like reference characters. 
     Depicted in  FIG. 4A  is a line  100  adjustably mounted on line lock  12 . Line  100  comprises a standing portion  102  in the form of a loop which extends below primary passageway  22 , a first working portion  104  which extends out of first working passageway  28 , and a first locking portion  106  extending therebetween. It is appreciated that each of the sections  102 ,  104 , and  106  of line  100  are relative to each other in that they change as line  100  is adjusted on line lock  10 . Line  100  further includes a second working portion  104 ′ which extends out of second working passageway  28 ′ and a second locking portion  106 ′ that extends between standing portion  102  and second working portion  104 ′. 
     First locking portion  106  extends up through primary passageway  22 , down through first secondary passageway  24 , and then up through first working passageway  28 . The section of locking portion  106  extending between primary passageway  22  and first secondary passageway  24  is referred to as compression section  110 . Line  100  passes up through first working passageway  28  so that first working portion  104  is disposed between compression section  110  and capture slot  34 . Second locking portion  106 ′ is similarly passed through passageways  22 ,  24 ′, and  28 ′. 
     During use, standing portion  102  of line  100  is typically looped around, embedded within, or passed through tissue, or some other structure. To secure standing portion  102  to the structure, unwanted slack is removed from standing portion  102 . This is accomplished by sliding line lock  10  over standing portion  102  and/or pulling on working portion  104  and/or  104 ′ so that the unwanted slack is pulled through line lock  10 . In either event, at least one of working portions  104  and  104 ′ increases in length while standing portion  102  shortens. 
     In the configuration depicted in  FIG. 4A , line  100  is passing through enlarged access regions  32  of working passageways  28  and  28 ′. In this position, relative locking portions  106  and  106 ′ freely slide through corresponding passageways of line lock  10  as the unwanted slack from standing portion  102  is removed. A mild tension force is typically applied to working portions  104  and  104 ′ as the unwanted slack is removed. The applied force pushes compression section  110  and  110 ′ back toward first side  19  of body  12  and thus away from capture slots  34 ,  34 ′. In turn, the portion of line  100  passing through primary passageway  22  and secondary passageways  24  and  24 ′ also naturally slides back within the passageways toward first side  19  of body  12 . This movement of line  100  helps to decrease frictional resistance on line  100 . 
     Once the slack is removed from standing portion  102 , further force is applied to working portions  104 ,  104 ′ and/or line lock  10  so as to tension locking portions  106 ,  106 ′ on line lock  10 . As depicted in  FIG. 4B , as line  100  is tensioned, the diverging side face  44  of primary passageway  22  and side face  56  of first secondary passageway  24  cause the portions of line  100  passing therethrough, and thus compression portion  110  extending therebetween, to slide toward first side  21  of body  12 . 
     Furthermore, as line  100  is tensioned, compression portions  110 ,  110 ′ are shortened causing them to move into a more linear orientation. As a result of the above, tensioning of line  100  causes compression portions  110 ,  110 ′ to force working portions  104 ,  104 ′ toward corresponding capture slots  34 ,  34 ′. In turn, at least a portion of line  100  within working passageways  28  and  28 ′ is forced into corresponding capture slots  34 ,  34 ′ so that line  100  is secured therein by wedged frictional engagement. That is, line  100  is secured by compression within capture slots  34 ,  34 ′ because line  100  has a diameter larger than the width of capture slots  34 ,  34 ′. Once line  100  is captured under compression in capture slots  34 ,  34 ′, line  100  will remain captured even if there is a complete loss of tension in standing end  102 . Thus, “locking” of line lock  10  to line  100  ensures that line lock  10  will not become separated from line  100 , even under cyclic changes in line tension in standing end  102 . Furthermore, line lock  10  is continuously adjustable in that further tension can be applied to standing portions  104  and/or  104 ′ at any time to remove additional slack from standing portion  102  while retaining line  100  locked to line lock  10 . 
     The passageways extending through line lock  10  are also configured such that as compression portions  110  and  110 ′ force line  100  into capture slots  34  and  34 ′, compression portions  110  and  110 ′ also fold and/or bias working ends  104  and  104 ′ over and/or against top outside corner  76  of capture slots  34  and  34 ′. In view of the relatively small radius of curvature of top outside corner  76 , the engagement between the captured working ends  104  and  104 ′ and top outside corner  76  creates a high degree of friction which forms a secondary locking mechanism between line  100  and line lock  10 . As such, the engagement between capture working ends  104  and  104 ′ and top outside corner  76  prevents backward movement of line lock  10  relative to line  100 . 
     In the embodiment depicted in  FIG. 4B , compression portion  110  is disposed above a portion of top outside corner  76  so as to directly bias working ends  104  against top outside corner  76 . Compression portion  110  is also shown disposed directly above a portion of working end  104  that is biasing against top outside corner  76 . In alternative embodiments, compression portion  110  when tensioned can extend between central passageway  22  and secondary passageways  24  without passing over working passageway  28 . That is, compression portion  110  can pass at a location toward second side  21  of line lock  10  that is spaced apart from working passageway  28 . In this embodiment, compression portion  110  still passes over working end  104 , thereby remotely causing working end  104  to fold over and bias against top outside corner  76 . 
     One of the unique features of the present embodiment is that as line lock  10  is advanced toward standing end  102  when standing end  102  is not under tension, i.e., when slack is being removed from standing end  102 , working ends  104  and  104 ′ tend to push away compression portions  110  and  110 ′, as discussed above, thereby minimizing frictional engagement between working ends  104 ,  104 ′, compression portions  110 ,  110 ′ and line lock  10 . As a result, line lock  10  can be easily advanced on line  100 . 
     Furthermore, unlike some other continuously adjustable line locks known in the art that use a loop portion to draw in and wedge a portion of a line within a bore hole, compression portions  110  and  110 ′ traverse a substantially straight path because they are constrained by secondary passageways  24  and  24 ′ and primary passageway  22 . This substantially straight path translates to a lower frictional resistance to sliding not possible with other adjustable line locks known in the art. 
     As previously discussed, line  100  is routed through passageways  22 ,  24 , and  28  so as to pass over the outside corners of the passageways. When a tensioned section of line  100  passes around a first outside corner of line lock  10 , friction produced between line  100  and the corresponding outside corner cause a decrease in tension on the portion of line  100  extending away from the outside corner on the side opposite the tensioned section. The friction produced at the outside corner must be overcome in order to cause line  100  to slide. Similarly, as the line passes around subsequent outside corners away from the tensioned section, each subsequent corner produces an incremental decrease in line tension and a corresponding incremental increase in friction that must be overcome to cause line  100  to slide. The loss in tension and increase in friction diminishes for each subsequent corner. Thus, the first corners are the most significant. 
     As depicted in  FIG. 6 , in view of the above discussion, when working end  104  is tensioned and standing end  102  is slack, line  100  extending from working end  104  toward line lock  10  first turns on bottom outside corner  78  of working passageway  28  and bottom outside corner  88  of secondary passageway  24 . As a result of the fact that these are the closest outside corners to tensioned working end  104 , outside corners  78  and  88  will produce the highest frictional resistance. Accordingly, to minimize the frictional resistance produced by outside corners  78  and  88  and thereby ease the sliding of line lock  10  toward standing end  102 , outside corners  78  and  88  are generously rounded as previously discussed. 
     In contrast, as depicted in  FIG. 5 , when standing end  102  is tensioned and working end  104  is slack, line  100  extending from standing end  102  toward line lock  10  first turns on top outside corner  66  of primary passageway  22  and top outside corner  86  of secondary passageway  24 . In view of the fact that these are the closest outside corners to tensioned standing end  102 , outside corners  66  and  86  will produce the highest frictional resistance. Accordingly, to maximize the frictional resistance produced by outside corners  66  and  86  and thereby minimizing slipping of line  100  once tensioned, outside corners  66  and  86  are formed relative sharp as previously discussed. More specifically, top outside corners  66  and  86  have a smaller radius of curvature than bottom outside corners  78  and  88 . It is noted that not all of each outside corner that bounds a corresponding opening has to have the same radius of curvature. For example, the portion of each outside corner that directly engages line  100  can have a radius of curvature that is different from the remainder of the corresponding outside corner. 
     Depicted in  FIG. 7 , line lock  10  is shown having an alternative routing of line  100 . To achieve this routing, working ends  104  and  104 ′ are passed up through secondary passageways  24  and  24 ′, respectively, down through primary passageway  22 , and then back up through working passageways  28  and  28 ′, respectively. Again compression portions  110  and  110 ′ are formed that selectively force working ends  104  and  104 ′ toward capture slots  34  as discussed above. In yet another alternative, it is appreciated that one end of line  100  can be routed as shown in  FIG. 4A  while the opposing end of line  100  is routed as shown in  FIG. 7 . 
     Depicted in  FIG. 8  is an alternative embodiment of a line lock  120 . It is noted that all common elements of alternative embodiments of line locks disclosed herein are identified by like reference characters. Line lock  120  comprises body  12  having primary passageway  22  and secondary passageways  24  and  24 ′ extending therethrough as discussed above with regard to  FIG. 1 . In contrast to the circumferentially closed working passageways  28 ,  28 ′, however, line lock  120  comprises working passageways  122  and  122 ′ that are circumferentially open. That is, each working passageway  122  and  122 ′ comprises an elongated tapered slot having a first end  124  and an opposing second end  126 . First end  124  is open along first side  19  of body  12  to facilitate convenient loading of line  100  therein. First end  124  also typically has a width greater than the diameter of line  100 . Second end  126  extends to a location between primary passageway  22  and a corresponding one of secondary passageway  24 ,  24 ′. 
     In this embodiment it is noted that the passageways are positioned such that a geometric line segment  130  can be extended between primary passageway  22  and secondary passageway  24 ′ such that line segment  130  does not intersect with working passageway  122 ′. However, a geometric line segment  132  can also be extended between primary passageway  22  and secondary passageway  24 ′ such that line segment  132  intersects with working passageway  122 ′. Second end  126  of each working passageway  122 ,  122 ′ typically has a width substantially equal to or smaller than the diameter of line  100 . 
     Depicted in  FIG. 9  is another alternative embodiment of a line lock  136  having substantially the same configuration as line lock  120 . In contrast to the circumferentially bounded primary passageway  22  and secondary passageways  24  and  24 ′ of line lock  120  in  FIG. 8 , however, line lock  136  comprises a partially bounded primary passageway  138  which is open at second side  21  of body  12  and partially bounded secondary passageways  140  and  140 ′ that are also each open at or adjacent to second side  21  of body  12 . 
     Two separate locking features were previously discussed with regard to securing line  100  to line lock  10 . Specifically, line  100  is secured by being wedged into capture slots  34  and  34 ′ and by biasing working portions  104  and  104 ′ against the top outside corner  76  of each working passageway  28 ,  28 ′. In alternative embodiments, it is appreciated that the locking features can be used independently. For example, depicted in  FIG. 10  is a line lock  144  having body  12  with secondary passageways  24  and  24 ′. In contrast to line lock  10 , however, line lock  144  comprises working passageways  146  and  146 ′ wherein capture slots  34  have been eliminated. Working passageways  146  and  146 ′ merely comprise elongated channels having a width substantially the same size or larger than the diameter of the line  100  to be passed therethrough. Line  100  is thus primarily secured to line lock  144  as a result of compression portions  110 ,  110 ′ biasing line  100  against top outside corner  76  of each working passageways  146  and  146 ′ as previously discussed. 
     Line lock  144  is also distinguished over line lock  10  in that primary passageway  22  has been replaced with a first primary passageway  148  and a spaced apart second primary passageway  148 ′. Primary passageways  148  and  148 ′ operate with opposing ends of line  100 . It is also noted that in alternative embodiments primary passageway(s) and/or the secondary passageways need not be elongated to allow the line passing therethrough to slide toward opposing sides  19  and  21  of body  12  as previously discussed with regard to line lock  10 . 
     Depicted in  FIG. 11  is an alternative embodiment of a line lock  150  that is designed to slide along a single strand of line  100 . Line lock  150  comprises a substantially disk shaped body  152  having a top surface  154  and an opposing bottom surface  156 . Extending through body  152  between surfaces  154  and  156  is a primary passageway  158  and a spaced apart secondary passageway  160 . Disposed between passageways  158  and  160  is a working passageway  162 . Similar to line lock  10 , working passageway  162  of line lock  150  has a first end with enlarged access region  32  and an opposing second end with constricted capture slot  34  thereat. 
     Primary passageway  158  and secondary passageway  160  have substantially the same elongated circular configuration which is similar to previously discussed secondary passageway  24 . Each of passageways  158  and  160  has an inside face  162  and  164 , respectively, that is disposed toward working passageway  162 . Each inside face  162  and  164  is substantially disposed in or is tangent to a corresponding plane  168  and  170 , respectively. Planes  168  and  170  converge toward capture slot  34  of working passageway  162  and diverge away from access region  32 . 
     Also extending through body  152  between top surface  154  and bottom surface  156  is an end passageway  172 . Although end passageway  172  can be positioned at a variety of different locations, end passageway  172  is shown aligned with working passageway  162  such that a plane extending between working passageway  162  and end passageway  172  separates primary passageway  158  from secondary passageway  160 . 
     During use, as depicted in  FIGS. 12A-12C , line  100  is routed through line lock  150  by passing working portion  104  from top surface  154  to bottom surface  156  through end passageway  172 , up through primary passageway  158 , down through secondary passageway  160 , and finally up through working passageway  162 . Compression portion  110  of line  100  extends between primary passageway  158  and secondary passageway  160  and is positioned to act upon working portion  104 . Line lock  150  can be selectively advanced by pulling working portion  104  away from top surface  154  so that line  100  travels through line lock  150 . Alternatively, line lock  150  can be manually slid toward standing portion  102 . In either event, the length of standing portion  102  is decreased. 
     As line  100  is tensioned on line lock  150 , line  100  locks on line lock  150  in substantially the same manner that line  100  locks with working passageway  28  as previously discussed with regard to line lock  10 . That is, compression portion  110  forces working end  104  toward capture slot  34  so that the portion of line  100  within working passageway  162  is captured by wedged frictional engagement within capture slot  34 . Furthermore, compression portion  110  either directly or indirectly biases working portion  104  against the top outside corner  76  of working passageway  162  at the second end thereof so as to increase the frictional engagement between line  100  and line lock  150 . Line lock  150  thus provides a continuously adjustable line lock or a one way sliding stop. In alternative embodiments, it is appreciated that line lock  150  can be modified in at least the same ways as discussed with the other line locks disclosed herein. 
     The embodiment shown in  FIGS. 12A-12C  is advantageous in certain applications where line lock  150  is positioned behind a first object and working portion  104  and standing portion  102  pass through the first object. In this situation, standing portion  102  is fixed to a second object. By pulling on working portion  104 , the first object is drawn irreversibly toward the second object. This is an advantage with surgical sutures where standing end  102  of a suture is attached to normal tissues and line lock  150  is placed behind tissue that has torn away. Standing portion  102  and working portion  104  pass through the torn tissue toward the normal tissue. By pulling on working portion  104  of suture, the torn tissue is pulled into apposition with the normal tissues and line lock  150  maintains the torn tissue adjacent to the normal tissue to facilitate healing of the tissue. 
     Depicted in  FIGS. 13A and 13B  is another embodiment of a line lock  180  incorporating features of the present invention. Line lock  180  also comprises a substantially disk shaped body  182  having a top surface  184  and an opposing bottom surface  186 . As with line lock  150 , line lock  180  includes primary passageway  158 , secondary passageway  160 , and working passageway  162 . Again, although not required, working passageway  162  is disposed such that a geometric line segment can be extended between primary passageway  158  and secondary passageway  160  so that the line segment intersects with working passageway  162 . In contrast to line lock  150 , line lock  180  does not include end passageway  172 . 
     Each of passageways  158 ,  160 , and  162  is configured to receive a double strand of line  100 . Specifically, during use both working end  104  and  104 ′ are passed up through primary passageway  158 , down through secondary passageway  160  and then back up through working passageway  162 . As a result, standing portion  102  is again formed in a loop that can be looped around, passed through, or otherwise secured to tissue or other structure. Unwanted slack is removed from standing portion  102  by again sliding line lock  180  on line  100  toward standing portion  102  and/or by pulling on one or both of working portions  104  and  104 ′ so that line  100  passes through line lock  180 . 
     When line  100  is tensioned on line lock  180 , compression portions  110  and  110 ′ force working portions  104 ,  104 ′ toward capture slot  34  so that a portion of each line section passing through working passageway  162  is captured by wedged frictional engagement within capture slot  34 . Compression portions  110  and  110 ′ also bias working portions  104  and  104 ′ toward and/or against top outsider corner  76  of working passageway  162  so as to increase the frictional engagement between line  100  and line lock  180 . As previously discussed with passageways  22 ,  24 , and  28  of line lock  10  in  FIGS. 1-6 , the radius of curvature of the top outside corner and bottom outside corner of each passageway  158 ,  160 , and  162  can be set so as to further control the ability of line  100  to slide or not slide through the passageway. Other alternatives as discussed with the line locks herein are also applicable to line lock  180 . In particular each of the passageways  158 ,  160 , and  162  can also be configured to receive a single strand of line  100 . In this configuration the single strand of line  100  is routed in a manner as described above for the double strand of line  100 . Instead of the standing portion  102  forming a loop when a double strand of line  100  is used, in this case the standing portion  102  consists of a free end which can be attached to tissue or other structures. 
     Depicted in  FIGS. 14A and 14B  is still another embodiment of a line lock  190  incorporating features of the present invention. Line lock  190  has substantially the same configuration as line lock  180  with like elements being referenced with like reference characters. The primary distinction between line locks  180  and  190  is that in line lock  190 , an end  192  of line  100  adjacent to standing portion  102  is secured to bottom surface  186  of body  182 . End  192  can be secured to body  182  by being integrally molded into body  182  or can be otherwise secured such as by welding or mechanical attachment. 
     Line lock  190  is also distinguished from line lock  180  in that passageways  158 ,  160 , and  162  need only be configured to receive a single strand of line  100 . That is, working end  104  passes up through primary passageway  158 , down through secondary passageway  160 , and then back up through working passageway  162 . Standing portion  102  is again substantially formed into a loop extending from end  192  of line  100  to primary passageway  158 . Because end  192  of line  100  is secured to body  182 , unwanted slack can be removed from standing portion  102  by pulling line  100  through line lock  190  and/or sliding line lock  190  down line  100 . Line  100  is locked to line lock  190  in substantially the same manner as discussed above with regard to the other line locks when line  100  is tensioned on line lock  190 . 
     And as previously described in U.S. application Ser. No. 11/001,866, after the working portion  104  has been inserted through or wrapped around the tissue to be retained, the line lock  190  may be advanced while holding the working portion  104  of the line  100  to tighten the standing portion  102 . Alternatively, the line lock  190  may be held in place while pulling on the working portion  104 . An insertion device (not shown) may be used to hold or advance the line lock  190 . 
     As tension in the standing portion  102  increases, the compression section  110  tightens and presses the underlying working portion  104  against the body  182 . The pressure on the working portion  104  keeps the working portion  104  from moving back into the working passageway  162 , thereby keeping the standing portion  102  from loosening. Thus, the tissue will be securely retained by the standing portion  102 , even after the working portion  104  has been cut short. 
     Pre-attachment of one end of a suture to a line lock, i.e., attachment of the suture prior to the surgical use, has a number of benefits. More specifically, it expedites installation of the suture and the line lock because separate sutures and line locks need not be located and assembled. As will be illustrated subsequently, a needle may also be pre-attached to the working end  104  of the line  100  so that all items needed for the suturing portion of the operation are ready for use. The line lock  190  may even be contained in a threader cartridge designed to facilitate insertion of the line  100  through the passageways  158 ,  160 ,  162  along the pattern illustrated. The configuration and use of such an assembly will be shown subsequently, in connection with  FIG. 61 . 
     In the embodiment of  FIGS. 14A and 14B , the end  192  may advantageously be attached to the line lock  190  via insert molding. According to one manufacturing method, the end  192  is positioned within an injection mold (not shown) used to form the line lock  190 . As the selected polymer fills the mold, it surrounds the end  192 . Then, as the selected polymer cools and hardens, it captures the end  192  in a substantially permanent manner. 
     The present invention contemplates the use of any known attachment method, including but not limited to insert molding, adhesive bonding, knotting, ultrasonic welding, looping, swaging, and fastening via mechanical fasteners such as bolts and clips, and the like.  FIGS. 54 through 59  provide examples of embodiments in which such alternative attachment methods are used. 
     Depicted in  FIG. 15  is still another embodiment of a line lock  200  incorporating features of the present invention. Line lock  200  comprises an elongated substantially box shaped body  202  comprising a top wall  204  and an opposing bottom wall  206  each extending between a first side wall  208  and a first end  210  and an opposing second side wall  212  and an opposing second end  214 . Also extending between top wall  204  and bottom wall  206  is a front wall  216  and an opposing back wall  218 . 
     Partially bounded within body  202  is a hollow chamber  220 . An access channel  222  is formed on front wall  216  so as to communicate with chamber  220 . Also communicating with chamber  220  is a primary passageway  224 . Primary passageway centrally extends through bottom wall  206  to chamber  220 . A first secondary passageway  226  extends through first side wall  208  so as to communicate with chamber  220  while a second secondary passageway  226 ′ extends through second side wall  212  so as to communicate with chamber  220 . A pair of first working passageways  228  and  228 ′ extend through bottom wall  206  and top wall  204 , respectively, in vertical alignment between primary passageway  224  and first secondary passageway  226 . 
     Similarly, a pair of second working passageways  230  and  230 ′ extend through bottom wall  206  and top wall  204  in vertical alignment between primary passageway  224  and second secondary passageway  226 ′. As with the prior working passageways, each of working passageways  228 ,  228 ′ and  230 ,  230 ′ has a first end towards front wall  226  with an enlarged axis region  32  and an opposing second end toward back wall  218  with a capture slot  34  formed thereat. 
     During use, as depicted in  FIG. 16A-16C , working portions  104  of line  100  are passed up through primary passageway  224  into chamber  220 . Working portion  104  then passes out of chamber  220  through first secondary passageway  226 . Finally, working portion  104  passes up through first working passageway  228 , through chamber  220 , and then out through first working passageway  228 ′. Compression portion  110  of line  100  extends from primary passageway  224  to first secondary passageway  226 . Working portion  104  is routed such that line  100  passes between compression portion  110  and back wall  218 . 
     In like manner, working portion  104 ′ extends from chamber  220  out through second secondary passageway  226 ′. Working portion  104 ′ then extends up through second working passageway  230 , through chamber  220 , and then out through second working passageway  230 ′. Again, line  100  extends between compression portion  110 ′ and back wall  218 . 
     As with the other embodiments, line lock  200  can be slid along line  100  and/or line  100  can be pulled therethrough so as to remove all unwanted slack from standing portion  102 . As line  100  is tension on line lock  200 , compression portions  110  and  110 ′ force the portion of line  100  extending between first working passageways  228  and  228 ′ and between second working passageways  230  and  230 ′, respectively, toward corresponding capture slots  34 . As a result, at least a portion of line  100  extending through each of the working passageways is captured by frictional wedge engagement within each of the corresponding capture slots  34 . Line  100  is thus locked with line lock  200 . 
     Line lock  200  offers several advantages. When standing end  102  is slack and working ends  104  and  104 ′ are tensioned, the sections of line  100  extending between working passageways  228  and  228 ′ and between working passageways  230  and  230 ′ force compression portions  110  and  110 ′, respectively, back toward front wall  216  so as to allow the free travel of line  100  through line lock  200 . In contrast, as discussed above, when tension is created in standing end  102  and slack is created in working ends  104  and  104 ′, compression portions  110  and  110 ′ force the sections of line  100  extending between working passageways  228  and  228 ′ and between working passageways  230  and  230 ′ toward back wall  218  so as to secure line  100  within the capture slots  34 . This back and forth movement of compression portions  110  and  110 ′ creates “backlash,” or a finite distance that line lock  200  can move away from standing end  102  until locking of line  100  is achieved. 
     Top wall  204  of line lock  200  provides a physical constraint to the amount of movement seen in compression portions  110  and  110 ′, thereby minimizing the amount of backlash. Furthermore, top wall  204  provides an additional friction point when compression portions  110  and  110 ′ compress against line  100 , thereby increasing the strength of the locking of line  100 . That is, one friction point is located at working passageways  228  and  230  on bottom wall  206  and the second friction point is located at working passageways  228 ′ and  230 ′ on top wall  204 . 
     It is again appreciated that the alternatives as discussed with the other embodiments are also applicable to line lock  200 . By way of example and not by limitation, line  100  can be routed through line lock  200  in a manner analogous to the routing in  FIG. 7 . The various passageways can be open or closed as depicted in  FIGS. 8 and 9 . Similarly, line lock  200  can be divided in half and modified to function similar to the line locks shown in  FIGS. 11-14 . 
     Depicted in  FIG. 17  is another alternative embodiment of a line lock  240  incorporating features of the present invention. Line lock  240  has a configuration similar to line lock  200  and thus like elements are identified by like reference characters. Line lock  240  comprises an elongated substantially box shaped body  242 . Similar to line lock  200 , body  242  comprises top wall  204  and bottom wall  206  extending between side wall  208  and side wall  212 . Body  242  also includes front wall  216  and back wall  218  which partially bound chamber  220 . 
     In contrast to line lock  200 , a first primary passageway  241  extends through first side wall  208  while second primary passageway  241 ′ extends through second side wall  212 . Primary passageways  241  and  241 ′ each communicate with chamber  220 . Body  242  of line lock  240  further comprises a first secondary passageway  244  extending through back wall  218  in communication with chamber  220  and a spaced apart second secondary passageway  244 ′ in communication with chamber  220 . A first access port  246  extends through front wall  216  in alignment with first secondary passageway  244 ′ so as to communicate with chamber  220 . Similarly, a second access port  246 ′ extends through front wall  216  in alignment with second secondary passageway  244  so as to also communicate with chamber  220 . 
     Furthermore, in contrast to the bounded working passageways of line lock  200 , line lock  240  comprises a pair of first working passageways  248  and  248 ′. Working passageway  248  comprises a constricting slot that is formed on bottom wall  206  and is open along intersecting front wall  216 . First working passageway  248 ′ is aligned with first working passageway  248  and is formed on top wall  204  so as to also be open along intersecting front wall  216 . A pair of second working passageways  250  and  250 ′ are similarly formed on bottom wall  206  and top wall  204  so as to be aligned with second secondary passageway  244 ′. Each of the working passageways terminates at capture slot having a width substantially equal to or smaller than the diameter of line  100 . 
     During use, as depicted in  FIGS. 18A-18C , working end  104  of line  100  is passed through first primary passageway  242  into chamber  220  and then out through first secondary passageway  244 . Working end  104  then passes down around bottom wall  206  and is then fed up through first working passageways  248  and  248 ′. A compression portion  110  of line  100  extends between primary passageway  241  and secondary passageway  244 . Working portion  104  is passed between working passageways  248 ,  248 ′ so that line  100  passes between compression portion  110  and first secondary passageway  244 . 
     Working portion  104 ′ is similarly passed through the passageways on the opposing side of line lock  240 . That is, working portion  104 ′ passes through primary passageway  241 ′ and into chamber  220 . Working portion  104 ′ then travels out through secondary passageway  244 ′, bends around bottom wall  206 , and then travels up through working passageways  250  and  250 ′. 
     In the above configuration, slack can be removed from standing portion  102  by pulling line  100  through line lock  240  and/or sliding line lock  240  toward standing portion  102 . As line  100  tensions on line lock  240 , compression portions  110  and  110 ′ again force portions of line  100  into capture slots  34  of the working passageways so as to secure line  100  to line lock  240  by wedged frictional engagement. 
     Like line lock  200 , line lock  240  provides containment of compression portions  110  and  110 ′ to minimize backlash. Unlike the other embodiments, line  100  is routed through line lock  240  such that at least one line turn exceeds 90 degrees. For example, the transition between compression portions  110  and  110 ′ and looping portions, designated as  252  and  252 ′, respectively, create 180 degree turns in line  100 . These sharp bends in line  100  increase the friction that must be overcome in order to advance line lock  240  toward standing end  102 . However, the sharp bends also contribute to greater locking strength of line lock  240  to line  100 . This embodiment is beneficial when line  100  is monofilament or single strand line, due to the commonly lower line on line friction and greater flexural stiffness of monofilament line when compared to braided or twisted strand line. 
     Referring to  FIG. 19 , a perspective view illustrates a line lock  310  according to one alternative embodiment of the invention. As shown, the line lock  310  has a body  312  that is generally disc-shaped. The body  312  has a top surface  314 , a bottom surface  316 , and a periphery  318  that extends between the top surface  314  and the bottom surface  316  to define a generally circular profile. In this application, a shape having a “generally circular profile” is any shape in which the outside boundary of any cross section passing through the main portion of the shape is substantially circular. 
     The body  312  bounds a plurality of passageways designed to cooperate receive a line such as a suture. In this application, passageways that “cooperate to receive” a line such as a suture receive the line such that the line passes through all of the cooperating passageways. The passageways of the body  312  include a first primary passageway  322  and a second primary passageway  323 , each of which may be positioned adjacent to the periphery  318 . The primary passageways  322 ,  323  are positioned on opposite sides of the body  312 . 
     Furthermore, in the line lock  310  of  FIG. 19 , the passageways include a first secondary passageway  324  and a second secondary passageway  325 , which are also positioned on opposite sides of the body  312 , adjacent to the periphery  318 . The secondary passageways  324 ,  325  may be positioned slightly closer to the periphery  318  than the primary passageways  322 ,  323 . Yet further, the passageways also include a first working passageway  328  and a second working passageway  329 . The working passageways  328 ,  329  are relatively centrally located with respect to the body  312 . 
     Each of the primary and secondary passageways  322 ,  323 ,  324 ,  325  may be generally rounded, and may optionally be somewhat elongated to provide an oval cross-section capable of receiving a doubled-over suture end, as when a suture end (not shown) is inserted through a loop (not shown) and drawn through the primary and secondary passageways  322 ,  323 ,  324 ,  325  via the loop. Each of the working passageways  328 ,  329  may also have a cross-section broad enough to receive a doubled-over suture end. 
     The passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  intersect the top surface  314  to form corresponding openings, each of which is bounded by one of a plurality of top outside corners  336 . The passageways  322 ,  323 ,  324 ,  324 ,  328 ,  329  also intersect the bottom surface  316  to form corresponding openings, each of which is bounded by one of a plurality of bottom outside corners (not shown). 
     As in the description previously set forth, some or all of the top outside corners  336  may have a smaller (i.e., sharper) radius than the corresponding bottom outside corners. More particularly, the top outside corners  336  of the working passageways  328 ,  329  may have comparatively small radii when compared to the bottom outside corners. In fact, in the embodiment of  FIG. 19 , the radii of the top outside corners  336  of the working passageways  328 ,  329  are considerably sharper than those of the top outside corners  336  of the primary and secondary passageways  322 ,  323 ,  324 ,  325 . The sharp radii of the top outside corners  336  of the working passageways  328 ,  329  enhances locking of the suture by the line lock  310 . 
     Each of the working passageways  328 ,  329  may have a shape that also facilitates locking of the suture, such as the teardrop-shaped cross-section illustrated in  FIG. 19 . More precisely, each of the working passageways  328  may have an access region  332  and a capture slot  334 . The access region  332  is large enough to permit the suture to pass therethrough with clearance. However, the capture slot  334  may be somewhat narrower such that, when the suture is drawn into the capture slot  334 , the walls of the capture slot  334  press against the suture to restrict further motion of the suture through the slot  334 . The operation of the capture slot  334  will be further shown and described in connection with  FIGS. 20 and 21 . 
     In the embodiment of  FIG. 19 , the first primary, secondary, and working passageways  322 ,  324 ,  328  are symmetrically arranged about the center of the body  312  with respect to the second primary, secondary, and working passageways  323 ,  325 ,  329 . In other words, the first primary, secondary, and working passageways  322 ,  324 ,  328  possess radial symmetry with respect to the second primary, secondary, and working passageways  323 ,  325 ,  329 . Accordingly, if the first primary, secondary, and working passageways  322 ,  324 ,  328  were rotated 180° about a central axis  338  of the body  312 , they would be substantially superimposed on the second primary, secondary, and working passageways  323 ,  325 ,  329 . 
     According to one alternative embodiment, the capture slots  334  may extend at angles with respect to the access regions  332  so that the working passageways  328 ,  329  may be more compactly arranged, while keeping the capture slots  334  at the desired position and orientation with respect to the first primary and secondary passageways  322 ,  324  and with respect to the second primary and secondary passageways  323 ,  325 . Such a configuration may potentially provide a more compact line lock (not shown) without losing suture locking capability. 
     In addition to the line lock  310 ,  FIG. 19  also illustrates an insertion tool  340  that may be used to insert a line lock such as the line lock  310  of  FIG. 19  into a relatively constricted space, such as a space within the body accessed via a cannula or the like. The insertion tool  340  has a proximal end (not shown), which may have handle or other structure to facilitate grasping by hand. The insertion tool  340  also has a distal end  342  and a hollow bore  344  that may extend along the entire displacement between the proximal end and the distal end  342  so that sutures or other items can be inserted into one end of the hollow bore  344  and retrieved from the opposite end. The distal end  342  has a rim  346 , which may have an annular shape, a frustoconical shape, or the like, such that the body  312  is able to seat against the rim  346 . The insertion tool  340  can thus be used to advance the line lock  310 . The insertion tool  340  is illustrated proximate the bottom side  316  of the body  312  for clarity in  FIG. 19 ; however, in use, the insertion tool  340  generally abuts the top side  314  and the periphery  318 . The manner in which the insertion tool  340  is used to advance the line lock  310  will be more fully set forth in the description of  FIG. 20 . 
     Referring to  FIG. 20 , a perspective view illustrates a system  348  including the line lock  310  of  FIG. 19  and a suture  350  relatively loosely passing through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  of the body  312 . The suture  350  may be similar or identical to that described previously. Accordingly, the suture  350  may have a standing portion  352 , which is the portion of the suture  350  that is placed under tension and constrained by advancement of the line lock  310 , first and second working portions  354 ,  355 , which are handled by a user, and first and second locking portions  356 ,  357  that are positioned between the standing portion  352  and the first and second working portions  354 ,  355 , respectively. 
     The suture  350  may be inserted through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  according to a wide variety of methods. For example, the suture  350  may be inserted by hand. Alternatively, the suture  350  may be inserted through the use of threaders (not shown) that are initially routed through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  along the proper pathways. The threaders may have leading ends designed to be drawn by hand, and trailing ends with loops or other features capable of capturing and drawing the suture ends. 
     Thus, a user may simply attach the ends of the suture  350  to the trailing ends of the threaders, and then pull the threaders until the suture  350  passes through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  along the desired pathways. The ends of the suture  350  may then be removed from the trailing ends of the threaders. In addition to or in the alternative to the use of threaders, a cartridge (not shown) may be used to retain the line lock  310  and guide the suture  350  through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  along the desired pathways. 
     As illustrated in  FIG. 20 , the first locking portion  356  extends from the standing portion  352  through the first primary passageway  322 , then through the first secondary passageway  324 , and then through the first working passageway  328 . From the first working passageway  328 , the first working portion  354  extends between the top surface  314  and the section of the first locking portion  356  that passes from the first primary passageway  322  to the first secondary passageway  324 . This section of the first locking portion  356  is a first compression section  360  of the suture  350 . 
     Similarly, the second locking portion  357  extends from the standing portion  352  through the second primary passageway  323 , then through the second secondary passageway  325 , and then through the second working passageway  329 . From the second working passageway  329 , the second working portion  355  extends between the top surface  314  and the section of the second locking portion  357  that passes from the second primary passageway  323  to the second secondary passageway  325 . This section of the second locking portion  357  is a second compression section  361  of the suture  350 . 
     As shown in  FIG. 20 , the first and second working portions  354 ,  355  have first and second compressed sections  362 ,  363 , respectively. The compressed sections  362 ,  363  underlie the corresponding compression sections  360 ,  361  of the first and second locking portions  356 ,  357 , respectively. When the compression sections  360 ,  361  become taught, they press the compressed sections  362 ,  363  against the top surface  314  of the body  312 . This will be explained in further detail subsequently. 
     The standing portion  352  may be inserted through and/or around some feature (not shown), such as bodily tissue, that is to be retained by the system  348 . The standing portion  352  may additionally or alternatively pass through an opening of a bone anchor or the like to enable tissues to be anchored to the bone, as in rotator cuff repair. From the configuration of  FIG. 20 , the suture  350  may be tightened by advancing the line lock  310  along the standing portion  352 . The line lock  310  may be advanced by holding the working portions  354 ,  355  and pressing the body  312  toward the standing portion  352 . 
     According to one method, the line lock  310  may be advanced along the standing portion  352  through the use of a tool such as the insertion tool  340  of  FIG. 19 . More precisely, the working portions  354 ,  355  may first be inserted into the hollow bore  344  at the distal end  342 . The working portions  354 ,  355  are inserted through the hollow bore  344  such that they protrude from the hollow bore  344  at the proximal end. A user may then grasp the working portions  354 ,  355  and draw them proximally, while holding the insertion tool stationary or advancing it distally, until there remains no slack in the working portions  354 ,  355 , and the body  312  is seated against the rim  346  of the distal end  342 . The shape of the rim  346  may tend to draw the body  312  into a position and orientation coaxial with the insertion tool  340  to facilitate insertion of the line lock  310  into a relatively narrow space. 
     Once the slack has been removed from the working portions  354 ,  355 , further tension on the working portions  354 ,  355  tends to cause the locking portions  356 ,  357  to advance through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329 , moving from the primary passageways  322 ,  323  toward the working passageways  328 ,  329 . Motion of the locking portions  356 ,  357  in this direction is relatively unrestricted since the compression sections  360 ,  361  remain slack, thereby allowing the locking portions  356 ,  357  to move through the access regions  332  of the working passageways  328 ,  329 . Consequently, the line lock  310  is able to advance along the standing portion  352 , thereby causing the standing portion  352  to tighten. 
     In alternative to use of a tool such as the insertion tool  340  of  FIG. 19 , the line lock  310  may be advanced along the standing portion  352  without any tooling. For example, the line lock  310  may be pressed and moved along the standing portion  352  by direct pressure from a finger. Alternatively, grasping the working portions  354 ,  355  and pulling them in substantially opposite and/or co-linear directions may cause the line lock  310  to advance along the standing portion  352 . Each of the working portions  354 ,  355  may then lie along the top surface  314 , but may not pass through the corresponding capture slot  334  until locking is performed. Such a technique may be particularly useful for retaining tissues in more readily accessible areas, where the working portions  354 ,  355  can be oriented and drawn in opposite directions. Use of insertion tooling may be more appropriate for more confined spaces. 
     Referring to  FIG. 21 , a perspective view illustrates the system  348  of  FIG. 20 , with the suture  350  routed relatively tightly through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329 . As the standing portion  352  tightens, tension in the standing portion  352  causes the compression sections  360 ,  361  to become taught. The compression sections  360 ,  361  straighten, thereby drawing the portions of the suture  350  within the working passageways  328 ,  329  outward, into the capture slots  334 . The compressed sections  362 ,  363  of the working portions  354 ,  355  adjacent to the working passageways  328 ,  329  are pinned against the top surface  314  by the compression sections  360 ,  361 . 
     Accordingly, each of the working portions  354 ,  355  is bent twice, with each bend having an angle of about ninety degrees. A first bend  370  is about the top outside corner  336  (as labeled in  FIG. 19 ) of each corresponding working passageway  328 ,  329 , and a second bend  372  is about the corresponding compression section  360 ,  361 . As mentioned previously, the top outside corners  336  of the working passageways  328 ,  329  have tight radii. Accordingly, the top outside corners  336  of the working passageways  328 ,  329  provide relatively high friction surfaces, particularly when the working portions  354 ,  355  are pressed against them via tension, like that applied by the compression sections  360 ,  361 . The compression sections  360 ,  361  may also provide considerable friction directly against the compressed sections  362 ,  363 , depending on the structure and material of the suture  350 . 
     Due to the friction applied to the bends  370 ,  372  of each of the working portions  354 ,  355  by the tensioned standing portion  352 , the working portions  354 ,  355  are generally unable to retract back into the working passageways  328 ,  329 . However, the standing portion  352  may still be tightened by further drawing on the working portions  354 ,  355 . Tension in the working portions  354 ,  355  tends to pull the compression sections  360 ,  361  inward, thereby removing the bends  370 ,  372  and relieving the associated sources of friction. Further advancement of the body  312  along the standing portion  352  only increases the level of tension in the standing portion  352  so that, when tension on the working portions  328 ,  329  is relieved, the working portions  328 ,  329  are again drawn to the locked configuration. 
     After the locking portions  356 ,  357  have been locked via tension in the standing portion  352 , the working portions  354 ,  355  may be cut short, for example, just outside the second bends  372 . The friction on the bends  370 ,  372  keeps slippage to a level low enough that cutting the working portions  354 ,  355  in such a manner does not impair the operation of the line lock  310 . The second bends  372  may disappear because there is no longer tension drawing the working portions  354 ,  355  to the orientation illustrated in  FIG. 21 . However, the second bends  372  are not required for locking; rather, the compression sections  360 ,  361  continue to press the compressed sections  362 ,  363  against the top surface  314 , adjacent to the first bends  370 . The friction of this compression interface, in addition to that of the first bends  370 , is sufficient to keep the suture  350  from slipping back through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329 . 
     If desired, the line lock  310  and/or the suture  350  may be formed of bioabsorbable or biodegradable materials. Alternatively, the line lock  310  and the suture  350  may be small and compact enough that they can remain in the body indefinitely without causing any discomfort or significant health risks. 
     Referring to  FIG. 22 , a perspective view illustrates a line lock  410  according to another alternative embodiment of the invention. The line lock  410  has a body  412  that is generally elongated, and is compactly designed for less intrusive insertion into the body, and for more rapid bioabsorption. The body  412  has a top surface  414 , a bottom surface  416 , and a periphery  418  extending between the top surface  414  and the bottom surface  416  to provide the elongated profile of the body  412 . 
     Furthermore, the body  412  is shaped to define a first primary passageway  422 , a second primary passageway  423 , a first secondary passageway  424 , a second secondary passageway  425 , and a first working passageway  428 . The first and second primary passageways  422 ,  423  and the first working passageway  428  are all fully bounded. The first and second secondary passageways  424 ,  425  are each only partially bounded. 
     As mentioned previously, the term “passageway,” as used in this application, is broadly interpreted to include partially bounded apertures, open channels, recesses, grooves, slots, and the like, that are capable of receiving a line and at least partially retaining the line therein. Accordingly, the structures labeled by reference numbers  424 ,  425  of  FIG. 22  are, indeed, passageways. The secondary passageways  424 ,  425  are contiguous with the periphery  418  because the bore of each of the secondary passageways  424 ,  425  transitions directly into the periphery  418 , with no significant intervening surface. 
     The first and second primary passageways  422 ,  423  are each generally circular in shape. The first working passageway  428  is designed to accommodate both locking portions  356 ,  357  of the suture  350  (not shown in  FIG. 22 ), and is thus elongated in shape. The first working passageway is positioned between the first and second primary passageways  422 ,  423  such that the passageways  422 ,  423 ,  428  are arrayed in a generally straight line along the length of the body  412 . 
     In  FIG. 22 , the first working passageway  428  has a generally rectangular shape, with semicircular arcs at the short ends. In alternative embodiments, any of a wide variety of shapes may be used, including trapezoidal, rectangular, square, triangular, circular, and oval shapes. If desired, alternative shapes may include one or more access regions and one or more capture slots, like those of the previous embodiment, that enhance suture locking. 
     The body  412  also defines a first groove  436  and a second groove  437 , both of which are formed in the top surface  414 . The first groove  436  extends along a generally straight path between the first primary and secondary passageways  422 ,  424 . Similarly, the second groove  437  extends along a generally straight path between the second primary and secondary passageways  423 ,  425 . The first and second grooves  436 ,  437  serve to enhance suture locking by the line lock  410  in a manner that will be set forth subsequently. 
     As shown in  FIG. 22 , the passageways  422 ,  423 ,  424 ,  425 ,  428  are symmetrical to each other about a central axis  338  of the body  412 . This is because, if rotated 180° about the central axis  338 , the first primary and secondary passageways  422 ,  424  would be superimposed on the second primary and secondary passageways  423 ,  425 , and the first working passageway  428  would be superimposed on itself. 
     Referring to  FIG. 23 , a perspective view illustrates a system  448  including the line lock  410  of  FIG. 22  and a suture  350 , like that illustrated in  FIGS. 20 and 21 . The suture  350  is shown routed relatively loosely through the passageways  422 ,  423 ,  424 ,  425 ,  428  of the line lock  410 . 
     The suture  350  may be routed through the passageways  422 ,  423 ,  424 ,  425 ,  428  of the line lock  410  in a manner similar to that of the line lock  310 . However, rather than being routed through two different working passageways  328 ,  329 , the locking portions  356 ,  357  are both routed through the first working passageway  428 . From the working passageway  428 , the first compressed section  362  of the first working portion  354  extends between the first compression section  360  and the first groove  436 , and the second compressed section  363  of the second working portion  355  extends between the second compression section  361  and the second groove  437 . 
     Referring to  FIG. 24 , a perspective view illustrates the system  448  of  FIG. 23 , with the suture  350  routed relatively tightly through the passageways  422 ,  423 ,  424 ,  425 ,  428  of the line lock  410 . The line lock  410  provides locking in a manner somewhat similar to that of the previous embodiment. More precisely, as the standing portion  352  of the suture  350  is tightened, tension is exerted on the compression sections  360 ,  361 . The compression sections  360 ,  361  then press the compressed sections  362 ,  363 , respectively, against the top surface  414  to cause the compressed sections  362 ,  363  to frictionally engage the grooves  436 ,  437 , respectively. As shown, the compression sections  360 ,  361  may extend generally parallel to the grooves  436 ,  437  and the compressed sections  362 ,  363  may extend generally perpendicular to the grooves  436 ,  437 . Accordingly, the working portions  354 ,  355  form bends where they extend across the grooves  436 ,  437 . The bends enhance locking by adding to the frictional resistance to motion of the working portions  354 ,  355 . 
     Other aspects of the operation of the line lock  410  are similar to those of the line lock  310  of the previous embodiment. The suture  350  may be inserted into the passageways  422 ,  423 ,  424 ,  425 ,  428 , tightened, and locked within the line lock  410  in any of the ways set forth in connection with the previous embodiment. An insertion tool (not shown) similar to the insertion tool  340  of  FIG. 19  may optionally be used to position the line lock  410  and/or move the line lock  410  along the locking portions  356 ,  357  of the suture  350 . Such an insertion tool may have a distal end with an elongated shape that corresponds to that of the body  412  in order to facilitate secure retention of the body  412  against the distal end during the implantation procedure. 
     As described in connection with the previous embodiment, the working portions  354 ,  355  may be cut short after the suture  350  has been tightened and locked by the line lock  410 . The line lock  410  may also be formed of a variety of bioabsorbable or non-bioabsorbable materials. The text setting forth potential suture threading methods, line lock advancement methods, materials, and the like for the line lock  310  may also apply to the line lock  410  and/or any other embodiment of the invention. 
     The line lock  410  has the advantage of being relatively compact. The overall dimensions of the body  412  are relatively small, and the volume occupied by the body  412  is also minimal. Accordingly, the line lock  410  may be easily implanted into relatively tight spaces, and if formed of a bioabsorbable material, may be readily absorbed by the body. The linear arrangement of the passageways  422 ,  423 ,  428  also keeps the line lock  410  from extending excessively along a direction transverse to that of the pathway followed by the suture  350 . In alternative embodiments, only two substantially bounded passageways may be used instead of three. One such embodiment will be shown and described connection with  FIGS. 25 through 27 . 
     Referring to  FIG. 25 , a perspective view illustrates a line lock  510  according to another embodiment of the invention. As in the previous embodiment, the line lock  510  has a body  512  with an elongated shape. The body  512  has a top surface  514 , a bottom surface  516 , and a periphery  518  arranged between the top surface  514  and the bottom surface  516  to define the elongated profile of the body  512 . The body  512  bounds a first primary passageway  522 , a second primary passageway  523 , a first secondary passageway  524 , and a second secondary passageway  525 . The first and second primary passageways  522 ,  523  are fully bounded, and the first and second secondary passageways  524 ,  525  are only partially bounded. No separate working passageway is needed. 
     The first and second primary passageways  522 ,  523  are each generally elongated in shape. Accordingly, each of the first and second primary passageways  522 ,  523  may receive both of the first or second locking portions  356 ,  357  of the suture  350  (not shown in  FIG. 25 ). This enables the first and second primary passageways  522 ,  523  to perform the function carried out by the working passageway  428  of the previous embodiment, as will be shown in greater detail in connection with  FIGS. 26 and 27 . 
     The body  512  also defines a first groove  536  and a second groove  537 , both of which are formed in the top surface  514 . The first groove  536  extends along a generally straight path between the first primary and secondary passageways  522 ,  524 . Similarly, the second groove  537  extends along a generally straight path between the second primary and secondary passageways  523 ,  525 . The first and second grooves  536 ,  537  serve to enhance suture locking by the line lock  510  in a manner similar to the grooves  436 ,  437  of the previous embodiment. 
     As shown in  FIG. 25 , the passageways  522 ,  523 ,  524 ,  525  are symmetrical to each other about a central axis  338  of the body  512 . This is because, if rotated 180° about the central axis  338 , the first primary and secondary passageways  522 ,  524  would be superimposed on the second primary and secondary passageways  523 ,  525 . 
     Referring to  FIG. 26 , a perspective view illustrates a system  548  including the line lock  510  of  FIG. 25  and a suture  350 , like that illustrated in  FIGS. 20 ,  21 ,  23 , and  24 . The suture  350  is shown routed relatively loosely through the passageways  522 ,  523 ,  524 ,  525  of the line lock  510 . 
     The suture  350  may be routed through the passageways  522 ,  523 ,  524 ,  525  of the line lock  510  in a manner similar to that of the line lock  410 . The first locking portion  356  passes through the first primary passageway  522 , then the first secondary passageway  524 . The second locking portion  357  passes through the second primary passageway  523 , and then the second secondary passageway  525 . Then, rather than passing through a working passageway  428 , the locking portions  356 ,  357  are again routed through the first and second primary passageways  522 ,  523 . More precisely, the first locking portion  356  passes through the second primary passageway  523 , and the second locking portion  357  passes through the first primary passageway  522 . From the second primary passageway  523 , the first compressed section  362  of the first working portion  354  extends between the first compression section  360  and the first groove  536 , and the second compressed section  363  of the second working portion  355  extends between the second compression section  361  and the second groove  537 . 
     Referring to  FIG. 27 , a perspective view illustrates the system  548  of  FIG. 26 , with the suture  350  routed relatively tightly through the passageways  522 ,  523 ,  524 , and  525  of the line lock  510 . The line lock  510  provides locking in a manner somewhat similar to that of the previous embodiment. More precisely, as the standing portion  352  of the suture  350  is tightened, tension is exerted on the compression sections  360 ,  361 . The compression sections  360 ,  361  then press the compressed sections  362 ,  363 , respectively, against the top surface  514  to cause the compressed sections  362 ,  363  to frictionally engage the grooves  536 ,  537 , respectively. As shown, the compression sections  360 ,  361  may extend generally parallel to the grooves  536 ,  537  and the compressed sections  362 ,  363  may extend generally perpendicular to the grooves  536 ,  537 . Accordingly, the working portions  354 ,  355  form bends where they extend across the grooves  536 ,  537 . The bends enhance locking by adding to the frictional resistance to motion of the working portions  354 ,  355 . 
     Other aspects of the operation of the line lock  510  are similar to those of the line locks  310 ,  410  of the previous two embodiments. The suture  350  may be inserted into the passageways  522 ,  523 ,  524 ,  525 , tightened, and locked within the line lock  510  in any of the ways set forth in connection with the previous embodiment. An insertion tool (not shown) similar to the insertion tool  340  of  FIG. 19  may optionally be used to position the line lock  510  and/or move the line lock  510  along the locking portions  356 ,  357  of the suture  350 . Such an insertion tool may have a distal end with an elongated shape that corresponds to that of the body  512  in order to facilitate secure retention of the body  512  against the distal end during the implantation procedure. 
     As described in connection with the embodiment of  FIGS. 19 through 21 , the working portions  354 ,  355  may be cut short after the suture  350  has been tightened and locked by the line lock  510 . The line lock  510  may also be formed of a variety of bioabsorbable or non-bioabsorbable materials. The text setting forth potential suture threading methods, line lock advancement methods, materials, and the like for the line lock  310  may also apply to the line lock  510  and/or any other embodiment of the invention. 
     And as previously described in U.S. application Ser. No. 10/936,376, referring to  FIG. 28 , a perspective view illustrates a line lock  1410  according to another alternative embodiment of the invention. As in the previous embodiment, the line lock  1410  has a body  1412  that is generally disc-shaped. The body  1412  has a top surface  1414 , a bottom surface  1416 , and a periphery  1418  extending between the top surface  1414  and the bottom surface  1416  to provide the generally circular profile of the body  1412 . Furthermore, the body  1412  bounds a first primary passageway  1422 , a second primary passageway  1423 , a first secondary passageway  1424 , and a second secondary passageway  1425 . The first passageways  1422 ,  1424  possess multiple forms of symmetry with respect to the second passageways  1423 ,  1425 , as will be described subsequently. The passageways  1422 ,  1423 ,  1424 ,  1425  are also adjacent to the periphery  1418 . 
     In addition to the passageways  1422 ,  1423 ,  1424 ,  1425 , the body  1412  bounds a first working passageway  1428 . The first working passageway  428  has an access region  1432  and a pair of capture slots  1434  extending from either side of the access region  1432 . The first working passageway  1428  accommodates both locking portions  356 ,  357  of the suture  350 . Accordingly, the access region  1432  is large enough to simultaneously receive two suture portions with clearance, and each of the capture slots  1434  is sized to compress one of the suture portions. 
     The body  1412  also defines a first groove  1436  and a second groove  1437 , both of which are formed in the top surface  1414 . The first groove  1436  extends along a generally arcuate path between the first primary and secondary passageways  1422 ,  1424 . Similarly, the second groove  1437  extends along a generally arcuate path between the second primary and secondary passageways  1423 ,  1425 . The first and second grooves serve to provide a pair of sharpened lips  1438  adjacent to each of the capture slots  1434  of the first working passageway  1428 . 
     As shown in  FIG. 28 , the passageways  1422 ,  1423 ,  1424 ,  1425 ,  1428  are symmetrical to each other about a central axis  338  of the body  1412 . This is because, if rotated 180° about the central axis  338 , the first primary and secondary passageways  1422 ,  1424  would be superimposed on the second primary and secondary passageways  1423 ,  1425 , and the first working passageway  1428  would be superimposed on itself. Furthermore, the passageways  1422 ,  1423 ,  1424 ,  1425 ,  1428  are symmetrical to each other about a plane  1440  passing through the center of the body  1412 . This is because, if reflected across the plane  1440 , the first primary and secondary passageways  1422 ,  1424  would be superimposed on the second primary and secondary passageways  1423 ,  1425 , and the first working passageway  1428  would be superimposed on itself. 
     The suture  350  may be routed through the passageways  1422 ,  1423 ,  1424 ,  1425 ,  1428  of the line lock  1410  in a manner similar to that of the line lock  310 . However, rather than being routed through two different working passageways  328 ,  329 , the locking portions  356 ,  357  are both routed through the first working passageway  1428 . From the working passageway  1428 , the first working portion  354  extends between the first compression section  360  and the first groove  1436 , and the second working portion  355  extends between the second compression section  361  and the second groove  1437 . 
     The line lock  1410  provides locking in a manner somewhat similar to that of the previous embodiment. More precisely, when the compression sections  360 ,  361  press the working portions  354 ,  355 , respectively, against the top surface  1414 , the suture  350  becomes wedged in the capture slots  1434 . Additionally, the compression sections  360 ,  361  press the working portions  354 ,  355  against the grooves  1436 ,  1437 , respectively. As shown, the compression sections  360 ,  361  may extend generally parallel to the grooves  1436 ,  1437  and the working portions  354 ,  355  may extend generally perpendicular to the grooves  1436 ,  1437 . Accordingly, the working portions form bends (not shown) where they extend over the sharpened lips  1438  of the grooves  1436 ,  1437 . The sharpened lips  1438  provide additional friction tending to resist motion of the working portions  354 ,  355  toward the first working passageway  1428 . 
     Otherwise, operation of the line lock  1410  is similar to that of the line lock  310  of the previous embodiment. The suture  350  may be inserted into the passageways  1422 ,  1423 ,  1424 ,  1425 ,  1428 , tightened, and locked within the line lock  1410  in any of the ways set forth in connection with the previous embodiment. As described above, the working portions  354 ,  355  may be cut short after the suture  350  has been tightened and locked by the line lock  410 . The line lock  1410  may also be formed of a variety of biodegradable or non-biodegradable materials. The text setting forth potential suture threading methods, line lock advancement methods, materials, and the like for the line lock  310  may also apply to the line lock  1410  and/or any other embodiment of the invention. 
     Referring to  FIG. 29 , a perspective view illustrates a line lock  1510  according to another embodiment of the invention. As in the previous embodiment, the line lock  1510  has a body  1512  with a disc-like shape. The body  1512  has a top surface  1514 , a bottom surface  1516 , and a periphery  1518  arranged between the top surface  1514  and the bottom surface  1516  to define the circular profile of the body  1512 . The body  1512  bounds a first primary passageway  1522 , a second primary passageway  1523 , a first secondary passageway  1524 , a second secondary passageway  1525 , and a first working passageway  1528 . 
     As in the previous embodiment, the first working passageway  1528  has an access region  1532  and a pair of oppositely disposed capture slots  1534 . However, in place of the grooves  1436 ,  1437  of the previous embodiment, the body  1512  has a central plateau  1536  around which the primary and secondary passageways  1522 ,  1523 ,  1524 ,  1525  are arranged. The first working passageway  1528  extends through the central plateau  1536 . 
     The central plateau  1536  may be somewhat tapered so as to form a sharpened rim  1538 . The central plateau  1536  has a concave surface  1540  that passes along a generally circular pathway between the sharpened rim  1538  and the remainder of the body  1512 . The sharpened rim  1538  has a pair of ears  1542  that extend between the first primary passageway  1522  and the second secondary passageway  1525 , and between the second primary passageway  1523  and the first secondary passageway  1524 . The top surface of the central plateau  1536  elevates as it extends outward, along the capture slots  1534 . 
     The suture  350  may be routed through the passageways  1522 ,  1523 ,  1524 ,  1525 ,  1528  of the line lock  1510  in a manner similar to that of the line lock  1410  of the previous embodiment. Accordingly, both locking portions  356 ,  357  of the suture  350  will extend through the first working passageway  1528 . The first working portion  354  will extend from the first working passageway  1528  to lie along the central plateau  1536  and the top surface  1514  between the first primary and secondary passageways  1522 ,  1524 . The second working portion  355  will extend from the first working passageway  1528  to lie along the central plateau  1536  and the top surface  1514  between the second primary and secondary passageways  1523 ,  1525 . 
     When the standing portion  352  is tensioned, the compression sections  360 ,  361  will compress the working portions  354 ,  355  against the sharpened rim  1538  of the central plateau  1536 , thereby forming bends and applying friction to keep the working portions  354 ,  355  from moving back toward the first working passageway  1528 . The sharpened rim  1538  effectively forms a function similar to that of the sharpened lips  1438  of the grooves  1436 ,  1437  of the previous embodiment. The compression sections  360  may tend to slide outward to either side of the central plateau  1536  to enhance the bends formed in the working portions  354 ,  355 . 
     Referring to  FIG. 30 , a perspective view illustrates a line lock  610  according to another alternative embodiment of the invention. The line lock  610  has a body  612  with a disc-like shape. The body  612  has a top surface  614 , a bottom surface  616 , and a periphery  618  that extends between the top surface  614  and the bottom surface  616  to define the generally circular profile of the body  612 . The body  612  bounds a first primary passageway  622  and a first secondary passageway  624 , but no second primary or secondary passageways. The first primary and secondary passageways  622 ,  624  are generally arc-shaped, and each of the first primary and secondary passageways  622 ,  624  is broad enough to accommodate multiple passes of the suture  350 . 
     The body  612  also bounds a first working passageway  628  and a second working passageway  629 . The working passageways  628 ,  629  may be shaped similarly to the working passageways  328 ,  329  of the embodiment of  FIG. 19 , in that each of the working passageways  628 ,  629  has a keyhole-like shape with an access region  632  sized to permit passage of the suture  350  with clearance, and a capture slot  634  sized to grip the suture  350 . The capture slots  634  are oriented inward, toward the center of the body  612 . 
     The body  612  also has a central depression  636  positioned between the first primary and secondary passageways  622 ,  624 . The central depression  636  may have a bowtie-like shape. The central depression  636  has side walls  638  that extend generally perpendicular to the top surface  614 . Sharpened edges  640  are formed by the intersection of the side walls  638  with the top surface  614 . The sharpened edges  640  serve to enhance locking of the suture  350  in a manner that will be set forth in connection with  FIGS. 31 and 32 . 
     Referring to  FIG. 31 , a perspective view illustrates a system  648  including the line lock  610  and the suture  350  passing through the passageways  622 ,  624 ,  628 ,  629  in a relatively loose configuration. As shown, the first locking portion  356  passes first through the first primary passageway  622 , and then through the first secondary passageway  624  to define the first compression section  360 . The second locking portion  357  passes first through the first secondary passageway  624  and then through the first primary passageway  622  to define the second compression section  361 . 
     From the first secondary passageway  624 , the first locking portion  356  passes through the first working passageway  628 , and the first working portion  354  extends from the first working passageway  628 , between the top surface  614  and the first compression section  360 . Similarly, from the first primary passageway  622 , the second locking portion  357  passes through the second working passageway  629 , and the second working portion  355  extends from the second working passageway  629 , between the top surface  614  and the second compression section  361 . 
     Referring to  FIG. 32 , a perspective view illustrates the assembly  648  of  FIG. 31 , with the suture  350  passing relatively tightly through the passageways  622 ,  624 ,  628 ,  629 . When the standing portion  352  is tensioned, the compression sections  360 ,  361  press the working portions  354 ,  355  against the top surface  614  and/or into the central depression  636 . The working portions  354 ,  355  are also pressed against the sharpened edges  640  to form bends in the working portions  354 ,  355  and to provide friction to keep the working portions  354 ,  355  from moving toward the working passageways  628 ,  629 , respectively. The sharpened edges  640  effectively serve a function similar to that of the sharpened rim  538  and the sharpened lips  1438  of previous embodiments. 
     Referring to  FIG. 33 , a perspective view illustrates a line lock  710  according to another alternative embodiment of the invention. As in previous embodiments, the line lock  710  has a body  712  with a disc-like shape. The body  712  has a top surface  714 , a bottom surface  716 , and a periphery  718  that extends between the top surface  714  and the bottom surface  716  to define the generally circular profile of the body  712 . The body  712  bounds a first primary passageway  722  and a first secondary passageway  724 . The first primary and secondary passageways  722 ,  724  are generally arc-shaped, and each of the first primary and secondary passageways  722 ,  724  is broad enough to accommodate multiple passes of the suture  350 . 
     The body  712  further bounds a first working passageway  728  and a second working passageway  729 . Each of the working passageways  728 ,  729  includes an access region  732  that is sized to permit passage of the suture  350  therethrough with clearance. Furthermore, the body  712  has a first trough  734  adjoining the first working passageway  728  and a second trough  735  adjoining the second working passageway  729 . The troughs  734 ,  735  are sized to press against the suture  350  to keep the suture  350  from sliding freely through the troughs  734 ,  735 . 
     The body  712  also has a central plateau  736 , a first groove  738 , and a second groove  739 . The grooves  738 ,  739  are positioned on either side of the central plateau  736  such that the first groove  738  lies between the central plateau  736  and the first working passageway  728  and the second groove  739  lies between the central plateau  736  and the second working passageway  729 . The grooves  738 ,  739  are relatively straight and connect opposing ends of the first primary and secondary passageways  722 ,  724  together. 
     The grooves  738 ,  739  define a pair of inner walls  740  and a pair of outer walls  742 , all of which extend generally perpendicular to the top surface  714 . The inner walls  740  also provide the sides of the central plateau  736  and define sharpened edges  744  where they intersect the top surface of the central plateau  736 . 
     Referring to  FIG. 34 , a perspective view illustrates a system  748  including the line lock  710  of  FIG. 27  and the suture  350  passing relatively loosely through the passageways  722 ,  724 ,  728 ,  729  of the line lock  710 . If desired, the suture  350  may be routed through the passageways  722 ,  724 ,  728 ,  729  in a manner very similar to that of the previous embodiment. Alternatively, as shown in  FIG. 34 , the first locking portion  356  may pass through the first secondary passageway  724 , then through the first primary passageway  722 , thereby defining the first compression section  360 , and then through the first working passageway  728 . Similarly, the second locking portion  357  may pass through the first primary passageway  722 , then the first secondary passageway  724 , thereby defining the second compression section  361 , and then through the second working passageway  729 . 
     From the first working passageway  728 , the first working portion  354  passes between the first compression section  360  and the top surface  614  and/or the first trough  734  and the first groove  738 . Similarly, from the second working passageway  729 , the second working portion  355  passes between the second compression section  361  and the top surface  714  and/or the second trough  735   
     Referring to  FIG. 35 , a perspective view illustrates the system  748  of  FIG. 34 , with the suture  350  routed relatively tightly through the passageways  722 ,  724 ,  728 ,  729  of the line lock  710 . When the standing portion  352  is tensioned, the compression sections  360 ,  361  press the working portions  354 ,  355  against the top surface  714 , the troughs  734 ,  735 , the grooves  738 ,  739 , and the sharpened edge  744 . The sharpened edge  744  helps to form a bend in each of the working portions  354 ,  355 , and to provide friction that keeps the working portions  354 ,  355  from moving back toward the working passageways  728 ,  729 . The working portions  354 ,  355  are also pressed into the troughs  734 ,  735 , which add additional friction. Part of each of the working portions  354 ,  355  may be pressed into the grooves  738 ,  739  to enhance bending of the working portions  354 ,  355 , thereby providing stronger locking. 
     Referring to  FIG. 36 , a perspective view illustrates a line lock  810  according to another alternative embodiment of the invention. As in previous embodiments, the line lock  810  has a body  812  with a generally disc-like shape. The body  812  has a top surface  814 , a bottom surface  816 , and a periphery  818  extending between the top surface  814  and the bottom surface  816  to define the generally circular profile of the body  812 . The body  812  bounds a first primary passageway  822 , a second primary passageway  823 , a first secondary passageway  824 , and a second secondary passageway  825 . All of the primary and secondary passageways  822 ,  823 ,  824 ,  825  are positioned proximate the periphery  818 . However, the body  812  does not bound any working passageways. 
     The primary and secondary passageways  822 ,  823 ,  824 ,  825  are shaped in a manner similar to those of the embodiment of  FIG. 19 , and may thus be somewhat elongated to permit them to receive a doubled-over suture end or the like. Since no working passageways are present, the suture  350  may pass outside the periphery  818 , and may rest against the periphery  818  in place of the bore of a working passageway. 
     For example, the standing portion of the suture  350  (not shown in  FIG. 36 ) may extend from the bottom surface  816 . The first locking portion  356  may pass through the first primary passageway  822 , then through the first secondary passageway  824  to define the first compression section  360 , and then around a first working portion  828  of the periphery  818 . Similarly, the second locking portion  357  may pass through the second primary passageway  823 , then through the second secondary passageway  825  to define the second compression section  361 , and then around a second working portion  829  of the periphery. Although the suture  350  is not illustrated in  FIG. 36 , the pattern applied to the suture  350  by engagement with the line lock  810  may be similar to that of  FIGS. 38 and 39 , which will be described subsequently. Alternatively, the pattern applied to the suture  350  by engagement of the line lock  810  may be similar to that of  FIGS. 41 and 42 , which will also be described subsequently. 
     When the line lock  810  is locked, the compression sections  360 ,  361  may press the working portions  354 ,  355  of the suture against the top surface  814 . The working portions  354 ,  355  must bend around the working portions  828 ,  829  of the periphery  818 , which serve to provide friction in addition to bending. If desired, the working portions  828 ,  829  may be sharpened, notched, or otherwise shaped to enhance the magnitude of friction they provide. As in other embodiments, the working portions  354 ,  355  also frictionally engage the compression sections  360 ,  361 . The line lock  810  of  FIG. 36  is relatively compact, and may be especially useful for tissue retention in highly constrained spaces. 
     Referring to  FIG. 37 , a perspective view illustrates a line lock  910  according to another alternative embodiment of the invention. The line lock  910  has a body  912  with a disc-like shape. The body  912  may have a top surface  914 , a bottom surface  916 , and a periphery  918  that extends between the top surface  914  and the bottom surface  916  to define the generally circular profile of the body  912 . As in the previous embodiment, the body  912  bounds a first primary passageway  922 , a second primary passageway  923 , a first secondary passageway  924 , and a second secondary passageway  925 . 
     Working passageways have again been omitted, and the periphery  918  includes first and second working portions  928 ,  929  along which the suture  350  may be routed in place of working passageways. Additionally, the body  912  has a first groove  936  extending between the first primary and secondary passageways  922 ,  924 , and a second groove  937  extending between the second primary and secondary passageways  923 ,  925 . The grooves  936 ,  937  define sharpened lips  938  where they intersect the top surface  914 . The sharpened lips  938  face outward, and each of the sharpened lips  938  has a generally arcuate shape similar to the generally arcuate shape of each of the grooves  936 ,  937 . 
     Referring to  FIG. 38 , a perspective view illustrates a system  948  including the line lock  910  and the suture  350 , with the suture  350  passing relatively loosely through the passageways  922 ,  923 ,  924 ,  925  of the line lock  910 . As shown, the first locking portion  356  passes through the first primary passageway  922 , then the first secondary passageway  924 , thereby defining the first compression section  360  of the suture  350 . Similarly, the second locking portion  357  passes through the second primary passageway  923 , then through the second secondary passageway  925  to define the second compression section  361  of the suture  350 . 
     The first locking portion  356  then passes around the first working portion  928  of the periphery  918 , and then between the top surface  914  and the first compression section  360 . By the same token, the second locking portion  357  then passes around the second working portion  929  of the periphery  918 , and then between the top surface  914  and the second compression section  361 . 
     Referring to  FIG. 39 , a perspective view illustrates the system  948  of  FIG. 38 , with the suture  350  passing relatively tightly through the passageways  922 ,  923 ,  924 ,  925  of the line lock  910 . When the standing portion  352  tightens, the compression sections  360 ,  361  press the working portions  354 ,  355  of the suture  350  against the grooves  936 ,  937  and the top surface  914 , including the sharpened lips  938 . The sharpened lips  938  provide bends in the working portions  354 ,  355 , and also exert frictional force on the working portions  354 ,  355  to keep them from moving toward the working portions  928 ,  929  of the periphery  918 . The compression sections  360 ,  361  may slide into the grooves  936 ,  937  to enhance bending of the working portions  354 ,  355 . 
     Referring to  FIG. 40 , a perspective view illustrates a line lock  1010  according to another alternative embodiment of the invention. The line lock  1010  has a body  1012  with a disc-like shape. The body  1012  has a top surface  1014 , a bottom surface  1016 , and a periphery  1018  extending between the top surface  1014  and the bottom surface  1016  to provide the generally circular profile of the body  1012 . The body  1012  bounds a first primary passageway  1022  and a second primary passageway  1023 . 
     Furthermore, the body  1012  partially bounds a first secondary passageway  1024  and a second secondary passageway  1025 . In the embodiment of  FIG. 40 , the secondary passageways  1024 ,  1025  take the form of notches formed in the periphery  1018 . As mentioned previously, the term “passageway,” as used in this application, is broadly interpreted to include partially bound apertures, open channels, recesses, grooves, slots, and the like, that are capable of receiving a line and at least partially retaining the line therein. Accordingly, the structures labeled by reference numbers  1024 ,  1025  of  FIG. 40  are, indeed, passageways. The secondary passageways  1024 ,  1025  are contiguous with the periphery  1018  because the bore of each of the secondary passageways  1024 ,  1025  transitions directly into the periphery  1018 , with no significant intervening surface. 
     The body  1012  also bounds a first working passageway  1028  and a second working passageway  1029 . The primary passageways  1022 ,  1023  and the working passageways  1028 ,  1029  may be shaped similarly to the primary and secondary passageways  322 ,  323 ,  324 ,  325  of the embodiment of  FIG. 19 , in that they are slightly elongated to permit passage of a doubled-over suture end. The body  1012  also has a first groove  1036  extending between the first primary passageway  1022  and the first secondary passageway  1024 , and a second groove  1037  extending between the second primary passageway  1023  and the second secondary passageway  1025 . 
     Referring to  FIG. 41 , a perspective view illustrates a system  1048  including the line lock  1010  of  FIG. 40  and the suture  350  passing relatively loosely through the passageways  1022 ,  1023 ,  1024 ,  1025 ,  1028 ,  1029  of the body  1012 . As shown, the first locking portion  356  of the suture  350  extends through the first primary passageway  1022 , then through the first secondary passageway  1024  to define the first compression section  360 . Similarly, the second locking portion  357  extends through the second primary passageway  1023 , then through the second secondary passageway  1025  to define the second compression section  361 . 
     From the first secondary passageway  1024 , the first locking portion  356  extends through the first working passageway  1028 , and then between the first compression section  360  and the top surface  1014  and the first groove  1036 . Similarly, from the second secondary passageway  1025 , the second locking portion  357  extends through the second working passageway  1029 , and then between the second compression section  361  and the top surface  1014  and the second groove  1037 . 
     Referring to  FIG. 42 , a perspective view illustrates the system  1048  of  FIG. 35 , with the suture  350  passing relatively tightly through the passageways  1022 ,  1023 ,  1024 ,  1025 ,  1028 ,  1029  of the body  1012 . When the standing portion  352  is tensioned, the compression sections  360 ,  361  press the working portions  354 ,  355  against the top surface  1014  and the grooves  1036 ,  1037 . The working portions  354 ,  355  lie generally perpendicular to the grooves  1036 ,  1037  and are pressed into the grooves  1036 ,  1037  to form a pair of bends in each of the working portions  354 ,  355 . The edges of the grooves  1036 ,  1037  also exert frictional force on the working portions  354 ,  355  to keep them from moving toward the working passageways  1028 ,  1029 . 
     Referring to  FIG. 43 , a perspective view illustrates a line lock  1110  according to another embodiment of the invention. As shown, the line lock  1110  has a body  1112  with a generally rectangular prismatic shape, with rounded corners. The body  1112  has a top surface  1114 , a bottom surface  1116 , and a periphery  1118  extending between the top surface  1114  and the bottom surface  1116  to define the generally rectangular profile of the body  1112 . The body  1112  at least partially bounds a plurality of passageways that enable the body  1112  to perform the function of half of the line lock  1010  of the previous embodiment, as will be set forth in greater detail below. 
     The passageways of the body  1112  include a first primary passageway  1122  fully bounded by the body  1112 , a first secondary passageway  1124  partially bounded by the body  1112 , and a first working passageway  1128  fully bounded by the body  1112 . The first primary, secondary, and working passageways  1122 ,  1124 ,  1128  are similar to their counterparts  1022 ,  1024 ,  1028  from the previous embodiment, and operate to retain the suture  350  in a similar manner. Additionally, the body  1112  includes a first groove  1136  similar to the first groove  1036  of the previous embodiment. 
     Referring to  FIG. 44 , a perspective view illustrates a system  1148  including the line lock  1110  and the suture  350  passing relatively loosely through the passageways  1122 ,  1124 ,  1128  of the body  1112 . The first locking portion  356  of the suture  350  passes through the first primary passageway  1122 , then through the first secondary passageway  1124  to define the first compression section  360  of the suture  350 . The first locking portion  356  then passes through the first working passageway  1128 . From the first working passageway  1128 , the first working portion  354  passes between the first compression section  360  and the top surface  1114  and the first groove  1136 . 
     Referring to  FIG. 45 , a perspective view illustrates the system  1148  of  FIG. 44 , with the suture  350  passing relatively tightly through the passageways  1122 ,  1124 ,  1128 . When the standing portion  352  is tensioned, the first compression section  360  presses the first working portion  354  against the top surface  1114  and the first groove  1136 . As in the previous embodiment, the first groove  1136  helps to form bends in the first working portion  354  and to exert frictional force to keep the first working portion  354  from moving back toward the first working passageway  1128 . Thus, as in previous embodiments, the first locking portion  356  is only able to move through the passageways  1122 ,  1124 ,  1128  along one direction. 
     In  FIGS. 44 and 45 , the working portion  352  is shown as an end, not a loop. However, the suture  350  need not terminate at the working portion  352  as shown, but may continue to provide the second locking portion  357  including the second compression section  361 , and then the second working portion  355  (not shown in  FIG. 44 ), as illustrated in connection with previous embodiments. The working portion  352  may then form a loop, and a second line lock (not shown) similar to the line lock  1110  may be used to lockably retain the second locking portion  357 . Thus, the two line locks may cooperate to retain tissue. 
     Alternatively, the working portion  352  may indeed terminate with no loop. The working portion  352  may instead be tied or otherwise attached to an anchor or the like, so that the line lock  1110  can be used to cinch tissue along the standing portion  352  by moving along only one length of the suture  350 . Since the line lock  1110  is only made to retain one length of the suture  350 , the line lock  1110  may be relatively compact by comparison with previous embodiments, and may thus be especially useful for tissue retention in constrained spaces. 
     Referring to  FIG. 46 , a perspective view illustrates a line lock  1210  according to another alternative embodiment of the invention. As in the previous embodiment, the line lock  1210  has a body  1212  with a generally rectangular prismatic shape, with rounded corners. The body  1212  has a top surface  1214 , a bottom surface  1216 , and a periphery  1218  extending between the top surface  1214  and the bottom surface  1216  to define the generally rectangular profile of the body  1212 . The body  1212  is configured similarly to the body  1112  of the previous embodiment, except that the body  1212  has passageways sized to simultaneously receive and lock multiple suture lengths. 
     More precisely, the body  1212  bounds a first primary passageway  1222 , partially bounds a first secondary passageway  1224 , and bounds a first working passageway  1228 . The first primary and working passageways  1222 ,  1228  are elongated so as to be capable of simultaneously receiving multiple suture lengths. The first secondary passageway  1224  is only partially bounded by the body  1212 , and may therefore be able to receive multiple suture lengths without elongation. As in the previous embodiment, the body  1212  also includes a first groove  1236  that extends between the first primary and secondary passageways  1222 ,  1224 . 
     Referring to  FIG. 47 , a perspective view illustrates a system  1248  including the line lock  1210  and the suture  350 , with the suture  350  passing relatively loosely through the passageways  1222 ,  1224 ,  1228  of the body  1212 .  FIG. 47  illustrates the standing portion  352 , both working portions  354 ,  355 , and both locking portions  356 ,  357  of the suture  350 , including both compression sections  360 ,  361 . The standing portion  352  is again illustrated as a loop. 
     As shown, the locking portions  356 ,  357  are routed through the passageways  1222 ,  1224 ,  1228  side-by-side. More precisely, the locking portions  356 ,  357  pass through the first primary passageway  1222 , then through the first secondary passageway  1224  to define the first and second compression sections  360 ,  361 . The locking portions  356 ,  357  then pass through the first working passageway  1228 . From the first working passageway  1228 , the working portions  354 ,  355  pass between the compression sections  360 ,  361  and the top surface  1214  and the first groove  1236 . 
     Referring to  FIG. 48 , a perspective view illustrates the system  1248  of  FIG. 47 , with the suture  350  relatively tightly passing through the passageways  1222 ,  1224 ,  1228  of the body  1212 . The compression sections  360 ,  361  press the working portions  354 ,  355  against the top surface  1214  and the first groove  1236 . The first groove  1236  helps to form bends in the working portions  354 ,  355  and to exert frictional force to keep the first working portions  354 ,  355  from moving back toward the first working passageway  1228 . Thus, as in previous embodiments, the locking portions  356 ,  357  are only able to move through the passageways  1222 ,  1224 ,  1228  along one direction. As in previous embodiments, the standing portion  352  may pass through an anchor or the like to enable usage of the line lock  1210  for tissue retention. 
     The present invention has particular relevance to surgery, and more particularly to tissue retention through the use of sutures. However, the principles, structures, and methods of the present invention may also be extended to other fields, including the use of larger line locks for locking ropes or cables in a wide variety of applications. 
     As previously described in U.S. application Ser. No. 10/942,275, referring to  FIG. 49 , a perspective view illustrates one embodiment of a system  2400  including the line lock  310  of  FIG. 19  (not visible in  FIG. 49 ), and various implements to help insert, or “thread,” the suture  350  through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  of the line lock  310 . A longitudinal direction  2402 , a lateral direction  2404 , and a transverse direction  2406  cooperate to form a system of orthogonal axes that will be used for reference in the following description. 
     In addition to the line lock  310 , the system  2400  includes a cartridge  2410 , a first threader  2412 , and a second threader  2414 . The cartridge  2410  contains the line lock  310  and, when in the closed configuration shown in  FIG. 49 , substantially encloses the line lock  310  to facilitate insertion of the suture  350  through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329 , and possibly, to help isolate the line lock  310  from contaminants. In this application, the phrase “substantially enclose” does not require full enclosure; rather, some portion(s) of the substantially enclosed part may protrude from the enclosure. 
     The cartridge  2410  may be formed of a plastic such as polypropylene, PEEK, or the like. The threaders  2412 ,  2414  pass through the cartridge  2410  along first and second pathways, respectively, to enable a user to draw the suture  350  through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  along the correct pattern, as will be described in greater detail subsequently. The threaders  2412 ,  2414  may be formed substantially of a fibrous material or a plastic, such as nylon. 
     As shown in  FIG. 49 , the cartridge  2410  has a first longitudinal end  2420 , a second longitudinal end  2422 , a first lateral end  2424 , and a second lateral end  2426 . The threaders  2412 ,  2414  pass through the longitudinal ends  2420 ,  2422 . Furthermore, the cartridge  2410  has a lid  2430  designed to move with respect to the remainder of the cartridge  2410 , which will be referred to as a containment portion  2432 . More specifically, a living hinge  2434  extends generally along the first lateral end  2424 , between the adjacent edges of the lid  2430  and the containment portion  2432 . The living hinge  2434  is integrally formed with the lid  2430  and the containment portion  2432  and flexes to enable pivotal motion of the lid  2430  with respect to the containment portion  2432 . In alternative embodiments, a conventional hinge may be used, or a lid may be slidable with respect to and/or fully removable from the remainder of the cartridge, thereby obviating the need for a hinging mechanism. 
     A first tab  2436  integrally formed with the lid  2430  and a second tab  2438  integrally formed with the containment portion  2432  may easily be pushed in opposite directions, for example, by a user&#39;s thumbs, to open the cartridge  2410 . The lid  2430  and the containment portion  2432  may be designed to adhere to each other at the second lateral end  2426  so that the cartridge  2410  only opens when a threshold force is applied. Thus, the cartridge  2410  may not open if dropped or jostled. 
     The first longitudinal end  2420  has a first set of slots  2440  through which the threaders)  2412 ,  2414  pass. Similarly, the second longitudinal end  2422  has a second set of slots  2442  through which the threaders  2412 ,  2414  pass. Thus, the threaders  2412 ,  2414  extend into the cartridge  2410  through the first longitudinal end  2420  and out again through the second longitudinal end  2422 . Each of the threaders  2412 ,  2414  has a leading end  2450  adjacent to the second set of slots  2442  and a trailing end  2452  adjacent to the first set of slots  2440 . 
     Each of the leading ends  2450  has a pull feature designed to facilitate grasping and drawing of the leading ends  2450  by hand. In the embodiment of  FIG. 49 , the pull features take the form of grips  2454  that may be easily grasped, for example, between a thumb and an index finger. The grips  2454  may be plastic rods crimped, insert molded, adhesive bonded, or otherwise attached to the remainder of the threaders  2412 ,  2414 . In alternative embodiments, differently configured pull features may be used, including rigid rings, flexible loops, spherical beads, squared beads, and the like. 
     Additionally, each of the trailing ends  2452  has a suture retention feature designed to retain a portion of a suture to enable the threaders  2412 ,  2414  to draw the suture through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  of the line lock  310 . In  FIG. 49 , the suture retention features take the form of eyelets  2456 , each of which is able to receive an end of the suture such that the suture end can double back on itself to be drawn through the cartridge  2410 . The eyelets  2456  may be crimped, adhesive bonded, insert molded, or otherwise attached to the remainder of the threaders  2412 ,  2414 . In alternative embodiments, differently configured suture retention features may be used, including adhesive-coated surfaces, collets, clips, flexible loops, and the like. 
     The eyelets  2456  may be retained to ensure that they are not drawn into the cartridge  2410  prior to attachment to the suture to be threaded through the line lock  310 . For example, the containment portion  2432  may have retention posts  2458  that extend in the longitudinal direction  2402  on either side of each of the slots of the first set of slots  2440 . Each of the eyelets  2456  may optionally be looped around a pair of the retention posts  2458  so that each eyelet  2456  is unable to enter the corresponding slot of the first set of slots  2440  until the eyelet  2456  is removed from around the retention posts  2458 . Each of the eyelets  2456  may need to be slightly larger than shown in  FIG. 49  to enable them to encircle a pair of the retention posts  2458 . The retention posts  2458  may also serve a similar function if loops or other flexible suture retention features are used in place of the eyelets  2456 . 
     Referring to  FIG. 50 , a perspective view illustrates the system  2400  of  FIG. 49 , with the cartridge  2410  in the open configuration to expose the line lock  310 . The suture  350  has also been inserted into engagement with the trailing ends  2452  of the threaders  2412 ,  2414 . More precisely, a first suture portion  2460  of the suture  350  has been inserted through the eyelet  2456  of the first threader  2412 , and a second suture portion  2462  of the suture  350  has been inserted through the eyelet  2456  of the second threader  2414 . The first and second suture portions  2460 ,  2462  are doubled back on themselves to permit the eyelets  2456  to draw them through the cartridge  2410  and through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  (not visible in  FIG. 50 ) of the line lock  310 . 
     Each of the suture portions  2460 ,  2462  may correspond to one or more of the various portions  352 ,  354 ,  355 ,  356 ,  357  of the suture  350 . However, no direct correlation is necessary because any portion(s) of the suture  350  may be drawn through the line lock  310  via the cartridge  2410  and the threaders  2412 ,  2414 . In the alternative to threading two portions of a suture through the line lock  310 , the system  2400  may be used to thread two separate sutures through the line lock  310 . 
     As shown in  FIG. 50 , the containment portion  2432  has a pair of sockets  2464  formed therein. Each of the sockets  2464  may provide a generally rectangular cavity surrounded by a wall that is slotted to permit expansion of the socket  2464 . The lid  2430  has a pair of posts  2466  that are generally rectangular in shape, and are sized and positioned to slide into the sockets  2464  when the cartridge  2410  is in the closed configuration. The posts  2466  may be sized to fit relatively tightly into the sockets  2464  so that the cartridge  2410  does not open until the threshold force is applied to remove the posts  2466  from the sockets  2464 . 
     The containment portion  2432  also has a central divider  2470  that extends generally along the lateral direction  2404  to effectively separate the containment portion  2432  into two separate compartments. The containment portion  2432  defines a retention feature designed to retain the line lock  310 . In this application, the terms “retention feature” and “threading feature” are to be broadly interpreted to include, not just single structural elements, but also groups of elements that cooperate to carry out line lock retention or suture threading. 
     In  FIG. 50 , the retention feature takes the form of a pair of troughs  2472  positioned on either side of a space in which the line lock  310  rests within the containment portion  2432 . The troughs  2472  face each other such that they retain the periphery  318  of the body  312  of the line lock  310  to resist motion of the line lock  310  along the longitudinal and transverse directions  2402 ,  2406 . The troughs  2472  are exposed on the open side of the containment portion  2432  so that the line lock  310  can be inserted into the space between the troughs  2472 , or removed therefrom, by moving the line lock  310  along the transverse direction  2406 . 
     Additionally, the containment portion  2432  has a threading feature designed to help guide the suture  350  through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  along the desired pattern. In  FIG. 50 , the threading feature takes the form of a pair of posts  2474  positioned on either side of the central divider  2470 , and thus on either side of the space in which the line lock  310  rests. Each of the posts  2474  may have a generally teardrop-shaped cross section, as taken through a plane parallel to the longitudinal and transverse directions  2402 ,  2406 . Each of the posts  2474  also has a slot  2476  facing the adjacent one of the first and second longitudinal ends  2420 ,  2422 . 
     The threaders  2412 ,  2414  are wrapped around the posts  2474  along a configuration similar to that provided by the suture  350  illustrated in  FIGS. 20 and 21 . More precisely, from its trailing end  2452 , the first threader  2412  passes through one of the first set of slots  2440 , then through the first primary passageway  322  (not visible in  FIG. 50 ) and then through the first secondary passageway  323  (not visible) to define a first loop  2480  of the first threader  2412 . From the first secondary passageway  323 , the first threader  2412  passes through the first working passageway  328  (not visible) to define a second loop  2482  of the first threader  2412 . From the first working passageway  328 , the first threader  2412  extends through the first loop  2480  and then passes through the corresponding one of the second set of slots  2442 , to the leading end  2450 . 
     Similarly, from its trailing end  2452 , the second threader  2414  passes through one of the first set of slots  2440 , then through the second primary passageway  2324  (not visible in  FIG. 50 ) and then through the second secondary passageway  325  (not visible) to define a first loop  2484  of the second threader  2414 . From the second secondary passageway  325 , the second threader  2414  passes through the second working passageway  329  (not visible) to define a second loop  2486  of the second threader  2414 . From the second working passageway  329 , the second threader  2414  extends through the first loop  2484  and then passes through the corresponding one of the second set of slots  2442 , to the leading end  2450 . 
     The various portions of the threaders  2412 ,  2414  may be positioned to correspond to portions of the suture  350 , as labeled in  FIGS. 20 and 21 . For example, the trailing ends  2452  may correspond to the standing portion  352  of the suture  350 , the leading ends  2450  may correspond to the working portions  354 ,  355 , and the loops  2480 ,  2482 ,  2484 ,  2486  may correspond to the locking portions  356 ,  357 . The first loops  2480 ,  2484  of the threaders  2412 ,  2414 , respectively, may more precisely correspond to the compression sections  360 ,  361  of the locking portions  356 ,  357 . Accordingly, when the suture  350  is drawn through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  by the threaders  2412 , the suture  350  assumes a configuration having the various portions  352 ,  354 ,  355 ,  356 ,  357  and sections  360 ,  361 , as illustrated in  FIGS. 20 and 21 . 
     As also shown in  FIG. 50 , the lid  2430  has a pair of blocking members  2490  that engage the posts  2474  when the cartridge  2410  is closed to keep the various loops  2480 ,  2482 ,  2484 , in place. More precisely, each of the blocking members  2490  has a longitudinal portion  2492  extending along the longitudinal direction  2402 , and a transverse portion  2494  extending along the transverse direction  2406 . The longitudinal portions  2492  may be positioned to seat in the slots  2476  of the posts  2474  to ensure that the loops  2480 ,  2482 ,  2484 ,  2486  cannot slip from the posts  2474  by moving laterally toward the lid  2430 , into a gap that may exist between the posts  2474  and the lid  2430 . Similarly, the transverse portions  2494  may be positioned inward of and adjacent to the first and second sets of slots  2440 ,  2442  to ensure that the leading and trailing ends  2450 ,  2452  of the threaders  2412 ,  2414  are unable to slide out of the slots  2440 ,  2442  by moving laterally toward the lid  2430 , into a gap that may exist between the slots  2440 ,  2442  and the lid  2430 . 
     Referring to  FIG. 51 , a perspective view illustrates the system  2400  of  FIG. 49 , with the cartridge  2410  open to expose the line lock  310 . In  FIG. 51 , the first threader  2412  is drawn partially through the cartridge  2410  so that the corresponding first suture portion  2460  of the suture  350  is partially drawn through the corresponding passageways  322 ,  324 ,  328  (not visible in  FIG. 51 ) of the line lock  310 . 
     More precisely, the first suture portion  2460  has been drawn through the corresponding one of the first set of slots  2420  and through the first primary passageway  322  (not visible in  FIG. 51 ) of the line lock  310 . Further, the first suture portion  2460  has been drawn along the first loop  2480  of the first threader  2412  so that the first suture portion  2460  encircles the post  2474  toward the second longitudinal side  2422 , in place of the first loop  2480 . 
     The leading, doubled-over portion of the first suture portion  2460  is thus poised to enter the first secondary passageway  324  (not visible). From the first secondary passageway  324 , the first suture portion  2460  will then be drawn along the second loop  2482  of the first threader  2412 , through the first working passageway  328  (not visible), and then through the corresponding one of the second set of slots  2442  in the second longitudinal end  2422 . The leading, doubled-over portion of the first suture portion  2460  will then protrude from the cartridge  2410  and may easily be grasped and drawn by hand until the line lock  310  is positioned at the desired location along the length of the first suture portion  2460 . 
     The second suture portion  2462  may be drawn through the cartridge  2410  in a similar manner, as described previously in connection with the discussion of  FIG. 50 . Thus, both suture portions  2460 ,  2462  may be drawn fully through the cartridge  2410  and through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  of the line lock  310 . The suture portions  2460 ,  2462  may be drawn through the cartridge  2410  with the cartridge in the open configuration, as illustrated in  FIG. 51 , or with the cartridge  2410  in the closed configuration. If desired, part or all of the cartridge  2410  may be made translucent or transparent so that a user can easily verify proper threading without opening the cartridge  2410 . 
     Referring to  FIG. 52 , a perspective view illustrates the system  2400  of  FIG. 49 , with the cartridge  2410  in the open configuration to expose the line lock  310 . The suture  350  has been fully threaded through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  of the line lock  310  in the manner illustrated in  FIGS. 20 and 21 . Accordingly, the line lock  310  need only be removed from the cartridge  2410  prior to use to retain tissue. 
     Referring to  FIG. 53 , a perspective view illustrates the system  2400  of  FIG. 49 , with the cartridge  2410  in the open configuration, and with the line lock  310  and the suture  350  removed from the cartridge  2410  for use. The line lock  310  has been drawn from the space between the troughs  2472  by drawing the line lock  310  along the lateral direction  2404 , toward the space the lid  2430  would occupy if the cartridge  2410  were closed. The first and second suture portions  2460 ,  2462  are also drawn along the same direction to slide free of the posts  2474  and the first and second sets of slots  2440 ,  2442 . 
     As shown, the various portions and sections  352 ,  354 ,  355 ,  356 ,  357 ,  360 ,  361  of the suture  350  are arranged substantially as shown in  FIGS. 20 and 21 . The standing portion  352  may connect the first and second suture portions  2460 ,  2461  together at a location not illustrated in  FIG. 53 . The standing portion  352  may be inserted through an anchor embedded in tissue, or otherwise positioned behind tissues to be retained by the system  2400 , prior to performance of the threading process set forth above. If the standing portion  352  is not required to pass through an enclosed aperture, the standing portion  352  may be positioned with respect to the tissue to be retained after the suture  350  has been threaded through the line lock  310 . 
     In alternative embodiments, the first and second suture portions  2460 ,  2462  may be two separate lengths of suture. The first and second suture portions  2460 ,  2462  may then be attached to their respective anchor points, or to each other, before or after they are threaded through the line lock  310 . If desired, the first and second suture portions  2460 ,  2462 , as separate sutures, may be attached to two different anchor points and the line lock  310  may be applied to draw the anchor points, and thereby the connected tissues, together. 
     As another alternative, the line lock  310  may only receive a single suture portion via the cartridge  2410  and one of the threaders  2412 ,  2414 . Such a single suture portion may be attached to an anchor at one end and tightened via the line lock  310  to retain tissue. As yet another alternative, a differently configured line lock (not shown) may be retained within the cartridge  2410  to receive a single suture portion. Such a line lock may operate as the functional equivalent of the line lock  310 , and may thus have only the first passageways  322 ,  324 ,  328 . 
     Returning to the configuration of  FIG. 53 , once the suture  350  has been properly threaded through the passageways  322 ,  323 ,  324 ,  325 ,  328 ,  329  (some of which are not visible in  FIG. 53 ), the line lock  310  may then be used to retain the tissue as desired. This may be accomplished by following the procedures outlined previously, i.e., holding the working portions  354 ,  355  and advancing the line lock  310  along the suture  350  to constrict the standing portion  352 , either with or without an insertion tool, and then trimming the suture  350 . 
     Thus, the suture  350  may easily be threaded through the line lock  310  in the proper pattern to ensure that the line lock  310  is able to perform as desired. Threading may be performed without significantly compromising the sterility of the line lock  310 , the suture  350 , or the operating environment. Thus, the convenience, reliability, and safety of tissue retention operations may be enhanced through the present invention. 
     And as previously described in U.S. application Ser. No. 11/001,866, referring to  FIG. 54 , a perspective view illustrates a line lock  2210  according to one alternative embodiment of the invention. The line lock  2210  has a body  2212  with a generally rectangular shape, with a top surface  2214 , a bottom surface  2216 , and a periphery  2218  that separates the top surface  2214  from the bottom surface  2216 . The body  2212  fully bounds a primary passageway  2222  and partially bounds a secondary passageway  2224 . In the embodiment of  FIG. 54 , the secondary passageway  2224  is defined by a portion of the periphery  2218  of the body  2212 . 
     The body  2212  also fully bounds a working passageway  2228  and a retention passageway  2230 . The retention passageway  2230  has a bore  2232  positioned to retain one end of a suture (not shown in  FIG. 54 ). The body  2212  further defines a groove  2236  extending between the primary and secondary passageways  2222 ,  2224 . The operation of the various passageways  2222 ,  2224 ,  2228 ,  2230  and the groove  2236  will be described in connection with  FIGS. 55 and 56 . 
     Referring to  FIG. 55 , a perspective view illustrates a system  2248  including the line lock  210  of  FIG. 54  and a line, or a suture  2250 , that may be locked by the line lock  2210 . The suture  2250  is relatively loosely routed through the passageways  2222 ,  2224 ,  2228  so that slack is present in the suture  2250 . 
     As shown, the suture  2250  has a standing portion  2252  that may be looped through or around the tissue to be retained. A working portion  2254  may be manipulated by a surgeon to control the slack in the standing portion  2252 . A locking portion  2256  separates the working portion  2254  from the standing portion  2252  and passes through the passageways  2222 ,  2224 ,  2228  in the manner illustrated. The locking portion  2256  includes a compression section  2260  that compresses the working portion  2254  against the body  2212  when the suture  2250  is tightened to prevent motion of the working portion  2254  through the working passageway  2228 . 
     As shown, the end of the suture  2250  adjacent to the standing portion  2252  is secured to the line lock  2210  via a knot  2262 . More precisely, the end of the suture  2250  has been inserted through the bore  2232  of the retention passageway  2230  (not visible in  FIG. 55 ), and then the knot  2262  has been tied in the end. The knot  2262  may be a simple overhand knot. The knot  2262  is too large to pass through the bore  2232 ; thus, the end of the suture  2250  is effectively secured to the line lock  2210 . 
     In this application, the word “secured,” with reference to a flexible member, means that some part of the flexible member is connected to an object so as to be inseparable from the object by tension on the flexible member in at least one direction. Thus, even though the knot  2262  may be withdrawn from the top surface  2214 , the fact that the knot  2262  is unable to pass through the top surface  2214  causes the end of the suture  2250  to be “secured” to the line lock  2210 . The term “direction,” when used in connection with motion of a flexible member such as a line, does not necessarily refer to a static vector. Rather, a “direction” may refer to motion of the line along a pathway, toward one specified end of the pathway. Thus, stating that a line is only able to move along a pathway in one direction means that the line can only be advanced toward one end of the pathway. The line moves along the pathway in one direction even though in the course of advancement along the pathway, segments of the line will simultaneously be moving along a variety of differently-oriented vectors. 
     The knot  2262  may be tied and the suture  2250  may be inserted through the bore  2232  prior to commencement of the surgical procedure. For example, the knot  2262  may be tied and the suture  2250  may be inserted through the bore  2232  at a manufacturing or packaging facility, prior to packaging of the line lock  2210  for shipping. The suture  2250  may then be shipped in the same package, preassembled with the line lock  2210  and ready for use. A needle (not shown) may similarly be included in the package. Thus, the surgeon need not select and assemble the various components needed to carry out the tissue retention procedure; rather, all necessary parts are already assembled and ready for use prior to commencement of the procedure. 
     From the end of the locking portion  2256  adjacent to the standing portion  2252 , the locking portion  2256  passes through the primary passageway  2222 , and then extends generally parallel to the groove  2236  to define the compression section  2260  and reach the secondary passageway  2224 . From the secondary passageway  2224 , the locking portion  2256  passes through the working passageway  2228 . The working portion  2254  then passes through the space between the compression section  2260  and the groove  2236 . 
     When tension is applied to the standing portion  2252 , as when the standing portion  2252  is tightened around one or more pieces of tissue, the compression section  2260  is drawn taught. The compression section  2260  presses the working portion  2254  against the groove  2236  to keep the working portion  2254  from being drawn back through the working passageway  2228 . 
     Referring to  FIG. 56 , a perspective view illustrates the system  2248 , with the suture  2250  routed relatively tightly through the passageways  2222 ,  2224 ,  2228  of the line lock  2210 . As described previously, the compression section  2260  presses the working portion  2254  against the groove  2236  to retain the working portion  2254 . As the working portion  2254  is pressed against the groove  2236 , bends (not shown) may be formed in the working portion  2254  as the working portion  2254  conforms to the shape of the groove  2236 . Such bends enhance locking of the working portion  2254  because there is greater friction keeping the working portion  2254  in place, and there is no direct path along which tension on the working portion  2254  can act to draw the working portion  2254  through the space between the compression section  2260  and the groove  2236 . Thus, the locking portion  2256  cooperates with the knot  2262  to retain both ends of the standing portion  2252 , thereby enabling the standing portion  2252  to securely retain tissue. 
     Referring to  FIG. 57 , a perspective view illustrates a line lock  1310  according to another alternative embodiment of the invention. The line lock  1310  has a body  1312  with a generally rectangular shape, with a top surface  1314 , a bottom surface  1316 , and a periphery  1318  that separates the top surface  1314  from the bottom surface  1316 . The body  1312  fully bounds a primary passageway  1322  and partially bounds a secondary passageway  1324 . As in the previous embodiment, the secondary passageway  1324  is defined by a portion of the periphery  1318  of the body  1312 . 
     The body  1312  also fully bounds a working passageway  1328  and a retention passageway  1330 . The retention passageway  1330  has a bore  1332  positioned to retain a loop of a suture (not shown in  FIG. 57 ). The body  1312  further defines a groove extending between the primary and secondary passageways  1322 ,  1324 . The primary passageway  1322 , the working passageway  1328 , and the groove  1336  may all be somewhat wider than their counterparts of the previous embodiment to permit two suture portions to be simultaneously routed therethrough. The operation of the various passageways  1322 ,  1324 ,  1328 ,  1330  and the groove  1336  will be described in connection with  FIGS. 58 and 59 . 
     Referring to  FIG. 58 , a perspective view illustrates a system  1348  including the line lock  1310  of  FIG. 57  and a line, or a suture  1350 , which may be locked by the line lock  1310 . The suture  1350  is relatively loosely routed through the passageways  1322 ,  1324 ,  1328  so that slack is present in the suture  1350 . 
     As shown, the suture  1350  has a standing portion  1352  with two separate strands, each of which may be looped through or around the tissue to be retained. First and second working portions  1354 ,  1355  may be manipulated by a surgeon to control the slack in the standing portion  1352 . First and second locking portions  1356 ,  1357 , respectively, separate the first and second working portions  1354 ,  1355 , respectively, from the standing portion  1352 . The locking portions  1356 ,  1357  pass through the passageways  1322 ,  1324 ,  1328  side-by-side, in the manner illustrated. 
     The first locking portion  1356  includes a first compression section  1360  that compresses the first and second working portions  1354 ,  1355  against the body  1312  when the suture  1350  is tightened to prevent motion of the first working portion  1354  through the working passageway  1328 . Similarly, the second locking portion  1357  includes a second compression section  1361  that compresses the first and second working portions  1354 ,  1355  against the body  1312  when the suture  1350  is tightened to prevent motion of the second working portion  1355  through the working passageway  1328 . 
     The suture  1350  also has a loop  1362  that passes through the bore  1332  of the retention passageway  1330 . The loop  1362  effectively secures the two strands of the working portion  1352  to the line lock  1310 , just as the knot  2262  of the previous embodiment secured the single strand of the working portion  2252  to the line lock  2210 . As with the knot  2262 , the loop  1362  may be inserted through the bore  1332  prior to commencement of the surgical procedure. For example, the loop  1362  may be inserted through the bore  1332  at a manufacturing or packaging facility, prior to packaging of the line lock  1310  for shipping such that the suture  1350  is shipped pre-attached to the line lock  1310 . A needle (not shown) may similarly be included in the package. 
     The first and second locking portions  1356 ,  1357  extend along a pathway similar to that followed by the locking portion  2256  of the previous embodiment. Accordingly, when the standing portion  1352  is drawn taught, the first and second compression sections  1360 ,  1361  press the first and second working portions  1354 ,  1355  against the groove  1336  to keep the working portions  1354 ,  1355  from moving back through the working passageway  1328 . 
     Referring to  FIG. 59 , a perspective view illustrates the system  1348 , with the suture  1350  routed relatively tightly through the passageways  1322 ,  1324 ,  1328  of the line lock  1310 . As described previously, the compression sections  1360 ,  1361  press the working portions  1354 ,  1355  against the groove  1336  to retain the working portions  1354 ,  1355 . Bends (not shown) may be formed in the working portions  1354 ,  1355  as the working portions  1354 ,  1355  conform to the shape of the groove  1336  to enhance locking of the working portions  1354 ,  1355 . Thus, the locking portions  1356 ,  1357  cooperate with the loop  1362  to retain both ends of the standing portion  1352 , thereby enabling the standing portion  1352  to securely retain tissue. 
     As mentioned previously, it may be desirable to package the line lock  190  in a cartridge that facilitates threading of the line  100  through the passageways  158 ,  160 ,  162 . One example of such a cartridge is illustrated in  FIGS. 60 through 64 , and is shown with respect to the line lock  190  of  FIGS. 14A and 14B . However, those of skill in the art will recognize that a similar cartridge may be provided for a line lock according to any other embodiment of the invention, such as the line locks  2210 ,  1310  of  FIGS. 54-59 . 
     Referring to  FIG. 60 , a perspective view illustrates one embodiment of a system  400  including the line lock  190  of  FIGS. 14A and 14B  (not visible in  FIG. 60 ), and various implements to help insert, or “thread,” the line  100  through the  158 ,  160 ,  162  of the line lock  190 . A longitudinal direction  3402 , a lateral direction  3404 , and a transverse direction  3406  cooperate to form a system of orthogonal axes that will be used for reference in the following description. 
     In addition to the line lock  190 , the system  3400  includes a cartridge  3410 , a threader  3412 , and a needle  3414 . The cartridge  3410  contains the line lock  190  and, when in the closed configuration shown in  FIG. 60 , substantially encloses the line lock  190  to facilitate insertion of the line  100  through the passageways  158 ,  160 ,  162 , and possibly, to help isolate the line lock  190  from contaminants. In this application, the phrase “substantially enclose” does not require full enclosure; rather, some portion(s) of the substantially enclosed part may protrude from the enclosure. 
     The cartridge  3410  may be formed of a plastic such as polypropylene, PEEK, or the like. The threader  3412  passes through the cartridge  3410  along a pathway to enable a user to draw the line  100  through the passageways  158 ,  160 ,  162  along the correct pattern, as will be described in greater detail subsequently. The threader  3412  may be formed substantially of a fibrous material or a plastic, such as nylon. 
     The needle  3414  is attached to the working end  104  of the line  100 , for example, by knotting, ultrasonic welding, swaging, or the like. The needle  3414  may be attached to the working end  104  prior to packaging of the system  3400  for shipping. Thus, the surgeon need not locate and attach an appropriate needle to the line  100  prior to surgical use. The needle  3414  may be any of a variety types suitable for surgical use. 
     As shown in  FIG. 60 , the cartridge  3410  has a first longitudinal end  3420 , a second longitudinal end  3422 , a first lateral end  3424 , and a second lateral end  426 . The threader  3412  passes through the longitudinal ends  3420 ,  3422 . Furthermore, the cartridge  3410  has a lid  3430  designed to move with respect to the remainder of the cartridge  3410 , which will be referred to as a containment portion  3432 . More specifically, a living hinge  3434  extends generally along the first lateral end  3424 , between the adjacent edges of the lid  3430  and the containment portion  3432 . The living hinge  3434  is integrally formed with the lid  3430  and the containment portion  3432  and flexes to enable pivotal motion of the lid  3430  with respect to the containment portion  3432 . In alternative embodiments, a conventional hinge may be used, or a lid may be slidable with respect to and/or fully removable from the remainder of the cartridge, thereby obviating the need for a hinging mechanism. 
     A first tab  3436  integrally formed with the lid  3430  and a second tab  3438  integrally formed with the containment portion  3432  may easily be pushed in opposite directions, for example, by a user&#39;s thumbs, to open the cartridge  3410 . The lid  3430  and the containment portion  3432  may be designed to adhere to each other at the second lateral end  3426  so that the cartridge  3410  only opens when a threshold force is applied. Thus, the cartridge  3410  may not open if dropped or jostled. 
     The first longitudinal end  3420  has a first set of slots  3440  through which the threader  3412  and the line  100  pass. More precisely, the threader  3412  passes through one slot of the first set of slots  3440 . From the end  192 , the standing portion  102  of the line  100  extends out of the cartridge  3410  through the other of the first set of slots  3440 . 
     Similarly, the second longitudinal end  3422  has a slot  3442  through which the threader  3412  passes. Thus, the threader  3412  extends into the cartridge  3410  through the first longitudinal end  3420  and out again through the second longitudinal end  3422 . The threader  3412  has a leading end  3450  adjacent to the second slot  3442  and a trailing end  3452  adjacent to the first set of slots  3440 . 
     The leading end  3450  has a pull feature designed to facilitate grasping and drawing of the leading end  3450  by hand. In the embodiment of  FIG. 60 , the pull feature takes the form of a grip  3454  that may be easily grasped, for example, between a thumb and an index finger. The grip  3454  may be a plastic rod crimped, insert molded, adhesive bonded, or otherwise attached to the remainder of the threader  3412 . In alternative embodiments, one or more differently configured pull features may be used, including rigid rings, flexible loops, spherical beads, squared beads, and the like. 
     Additionally, the trailing end  3452  has a suture retention feature designed to retain a portion of the line  100  to enable the threader  3412  to draw the line  100  through the passageways  158 ,  160 ,  162  of the line lock  190 . In  FIG. 60 , the suture retention feature takes the form of an eyelet  3456 , which is able to receive an end of the line  100  such that the end can double back on itself to be drawn through the cartridge  3410 . The eyelet  3456  may be crimped, adhesive bonded, insert molded, or otherwise attached to the remainder of the threader  3412 . In alternative embodiments, one or more differently configured suture retention features may be used, including adhesive-coated surfaces, collets, clips, flexible loops, and the like. 
     The eyelet  3456  may be retained to ensure that it is not drawn into the cartridge  3410  prior to attachment to the line  100 . For example, the containment portion  3432  may have retention posts  3458  that extend in the longitudinal direction  3402  on either side of the slots of the first set of slots  3440  through which the threader  3412  passes. The eyelet  3456  may optionally be looped around the retention posts  3458  so that the eyelet  3456  is unable to enter the corresponding slot of the first set of slots  3440  until the eyelet  3456  is removed from around the retention posts  3458 . The eyelet  3456  may need to be slightly larger than shown in  FIG. 60  to enable it to encircle a pair of the retention posts  3458 . The retention posts  3458  may also serve a similar function if a loop or other flexible suture retention feature is used in place of the eyelet  3456 . 
     Referring to  FIG. 61 , a perspective view illustrates the system  3400  of  FIG. 60 , with the cartridge  3410  in the open configuration to expose the line lock  190 . The line  100  has also been inserted into engagement with the trailing end  3452  of the threader  3412 . More precisely, the needle  3414  and the working portion  104  have already been inserted through or around the tissue or tissues to be retained, and the needle  3414  has been removed from the working portion  104 . The working portion  104  has then been inserted through the eyelet  3456  of the threader  3412 . The working portion  104  is doubled back on itself to permit the eyelet  3456  to draw it through the cartridge  3410  and through the passageways  158 ,  160 ,  162  (not visible in  FIG. 61 ) of the line lock  190 . 
     In alternative embodiments, multiple sutures or ends may need to be inserted through passageways of a line lock, such as the line lock  1310  of  FIGS. 57 through 59 . A cartridge (not shown) for such an embodiment may have multiple threaders, each of which is positioned to draw one suture or one end through the corresponding passageways. Operation of such a cartridge may otherwise be similar to that of the cartridge  3410 . 
     Returning to  FIG. 61 , the containment portion  3432  has a pair of sockets  3464  formed therein. Each of the sockets  3464  may provide a generally rectangular cavity surrounded by a wall that is slotted to permit expansion of the socket  3464 . The lid  3430  has a pair of posts  3466  that are generally rectangular in shape, and are sized and positioned to slide into the sockets  3464  when the cartridge  3410  is in the closed configuration. The posts  3466  may be sized to fit relatively tightly into the sockets  3464  so that the cartridge  3410  does not open until the threshold force is applied to remove the posts  3466  from the sockets  3464 . 
     The containment portion  3432  also has a central divider  3470  that extends generally along the lateral direction  3404  to effectively separate the containment portion  3432  into two separate compartments. The containment portion  3432  defines a retention feature designed to retain the line lock  190 . In this application, the terms “retention feature” and “threading feature” are to be broadly interpreted to include, not just single structural elements, but also groups of elements that cooperate to carry out line lock retention or suture threading. 
     In  FIG. 61 , the retention feature takes the form of a pair of troughs  3472  positioned on either side of a space in which the line lock  190  rests within the containment portion  3432 . The troughs  3472  face each other such that they retain the line lock  190  to resist motion of the line lock  190  along the longitudinal and transverse directions  3402 ,  3406 . The troughs  3472  are exposed on the open side of the containment portion  3432  so that the line lock  190  can be inserted into the space between the troughs  3472 , or removed therefrom, by moving the line lock  190  along the transverse direction  3406 . 
     Additionally, the containment portion  432  has a threading feature designed to help guide the line  100  through the passageways  158 ,  160 ,  162  along the desired pattern. In  FIG. 61 , the threading feature takes the form of a pair of posts  3474  positioned on either side of the central divider  3470 , and thus on either side of the space in which the line lock  190  rests. Each of the posts  3474  may have a generally teardrop-shaped cross section, as taken through a plane parallel to the longitudinal and transverse directions  3402 ,  3406 . Each of the posts  3474  also has a slot  3476  facing the adjacent one of the first and second longitudinal ends  3420 ,  3422 . 
     The threader  3412  is wrapped around the posts  3474  along a configuration similar to that provided by the line  100  illustrated in  FIGS. 14A and 14B . More precisely, from its trailing end  3452 , the threader  3412  passes through one of the first set of slots  3440 , then through the primary passageway  158  (not visible in  FIG. 61 ) and then through the secondary passageway  160  (not visible) to define a first loop  3484  of the threader  3412 . From the secondary passageway  160 , the threader  3412  passes through the working passageway  162  (not visible) to define a second loop  3486  of the first threader  3412 . From the working passageway  162 , the threader  3412  extends through the first loop  3484  and then passes through the second slot  3442 , to the leading end  3450 . 
     The various portions of the threader  3412  may be positioned to correspond to portions of the line  100 , as labeled in  FIGS. 14A and 14B . For example, the trailing end  3452  may correspond to the standing portion  102  of the line  100 , the leading end  3450  may correspond to the working portion  104 , and the loops  3484 ,  3486  may correspond to the locking portion  106 . The first loop  3484  of the threader  3412  may more precisely correspond to the compression section  110  of the locking portions  106 . Accordingly, when the line  100  is drawn through the passageways  158 ,  160 ,  162  by the threader  3412 , the line  100  assumes a configuration having the various portions  102 ,  104 ,  106 , as illustrated in  FIGS. 14A and 14B . 
     As also shown in  FIG. 61 , the lid  3430  has a pair of blocking members  3490  that engage the posts  3474  when the cartridge  3410  is closed to keep the first and second loops  3484 ,  3486  in place. More precisely, each of the blocking members  3490  has a longitudinal portion  3492  extending along the longitudinal direction  3402 , and a transverse portion  3494  extending along the transverse direction  3406 . The longitudinal portions  3492  may be positioned to seat in the slots  3476  of the posts  3474  to ensure that the loops  3484 ,  3486  cannot slip from the posts  3474  by moving laterally toward the lid  3430 , into a gap that may exist between the posts  3474  and the lid  3430 . Similarly, the transverse portions  3494  may be positioned inward of and adjacent to the first set of slots  3440  and to the second slot  3442  to ensure that the leading and trailing ends  3450 ,  3452  of the threader  3412  are unable to slide out of the slots  3440 ,  3442  by moving laterally toward the lid  3430 , into a gap that may exist between the slots  3440 ,  3442  and the lid  3430 . 
     Referring to  FIG. 62 , a perspective view illustrates the system  3400  of  FIG. 62 , with the cartridge  3410  open to expose the line lock  190 . In  FIG. 62 , the threader  3412  is drawn partially through the cartridge  3410  so that the working portion  104  of the line  100  is drawn partially along the pathway followed by the threader  3412 . More precisely, the working portion  104  has been drawn through the corresponding one of the first set of slots  3420  and through the primary passageway  158  (not visible in  FIG. 62 ) of the line lock  190 . Further, the working portion  104  has been drawn along the first loop  3484  of the threader  3412  so that the working portion  104  encircles the post  3474  toward the second longitudinal side  3422 , in place of the first loop  3484 . 
     The leading, doubled-over portion of the working portion  104  is thus poised to enter the secondary passageway  160  (not visible). From the secondary passageway  160 , the working portion  104  will then be drawn along the second loop  3486  of the threader  3412 , through the working passageway  162  (not visible), and then through the second slot  3442  in the second longitudinal end  3422 . The leading, doubled-over portion of the working portion  104  will then protrude from the cartridge  3410  and may easily be grasped and drawn by hand until the line lock  190  is positioned at the desired location along the length of the line  100 . 
     The line  100  may be drawn through the cartridge  3410  with the cartridge in the open configuration, as illustrated in  FIG. 62 , or with the cartridge  3410  in the closed configuration. If desired, part or all of the cartridge  3410  may be made translucent or transparent so that a user can easily verify proper threading without opening the cartridge  3410 . 
     Referring to  FIG. 63 , a perspective view illustrates the system  3400  of  FIG. 60 , with the cartridge  3410  in the open configuration to expose the line lock  190 . The line  100  has been fully threaded through the passageways  158 ,  160 ,  162  of the line lock  190  in the manner illustrated in  FIGS. 14A and 14B . Accordingly, the line lock  190  need only be removed from the cartridge  3410  prior to use to retain tissue. 
     Referring to  FIG. 64 , a perspective view illustrates the system  3400  of  FIG. 60 , with the cartridge  3410  in the open configuration, and with the line lock  190  and the line  100  removed from the cartridge  3410  for use. The line lock  190  has been drawn from the space between the troughs  3472  by drawing the line lock  190  along the transverse direction  3406 , toward the space the lid  3430  would occupy if the cartridge  3410  were closed. The line  100  is also drawn along the same direction to slide free of the posts  3474  and the slots  3440 ,  3442 . 
     As shown, the various portions and sections  102 ,  104 ,  106 ,  110  of the line  100  are arranged substantially as shown in  FIGS. 14A and 14B . The standing portion  102  may be inserted through an anchor embedded in tissue, or otherwise positioned behind tissues to be retained by the system  400 , prior to performance of the threading process set forth above. If the standing portion  102  is not required to pass through an enclosed aperture, the standing portion  102  may be positioned with respect to the tissue to be retained after the line  100  has been threaded through the line lock  190 . 
     Once the line  100  has been properly threaded through the passageways  158 ,  160 ,  162 , the line lock  190  may then be used to retain the tissue as desired. This may be accomplished by following the procedures outlined previously, i.e., holding the working portion  104  and advancing the line lock  190  along the line  100  to constrict the standing portion  102 , either with or without an insertion tool, and then trimming the line  100  to the desired length. 
     Thus, the line  100  may easily be threaded through the line lock  190  in the proper pattern to ensure that the line lock  190  is able to perform as desired. Threading may be performed without significantly compromising the sterility of the line lock  190 , the line  100 , or the operating environment. Thus, the convenience, reliability, and safety of tissue retention operations may be enhanced through the present invention. 
     According to one alternative embodiment of the invention, one end of a suture may be removably or permanently secured to a line lock, and the other end may be received by a plurality of passageways in such a manner that the second end is only able to move through the passageways along one direction. The first end may be secured to the line lock via insert molding, knotting, ultrasonic welding, adhesive bonding, or the like. The passageways that receive the second end may be arranged in a manner similar to any of those described in the embodiments set forth above, or equivalents thereof. 
     The present invention has particular relevance to surgery, and more particularly to tissue retention through the use of sutures. However, the principles, structures, and methods of the present invention may also be extended to other fields, including the use of larger line locks for locking ropes or cables in a wide variety of applications. 
     While the present invention has application to any need for securing a line, it is particularly advantages to surgical suture applications as a way to conveniently and reliable replace the need to tie suture knots. The advantage is even greater in arthroscopic and endoscopic applications, where sophisticated sliding knots followed by “back-up” knots must be tied outside of a cannula and slid into final position at an internal body site. The sophisticated sliding knots are difficult to tie, time consuming, and bulky. The present invention provides an easy to apply, quick to deliver, and low profile solution that will reliably maintain the desired suture tension. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. For example, above are described various alternative examples of different adjustable line locks. It is appreciated that various features of the line locks can be mixed and matched to form a variety of other alternatives, a different threading system according to the invention. As such the described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.