Abstract:
Some embodiments of the present invention include a suture anchor with both knotless and knotted suture attachment capabilities, as well as methods for loading the suture in knotless and knotted configurations. Some embodiments of the present invention include a suture anchor with an inner implant body with a spreader that slides in relation to an outer expandable collar, such that pushing the expandable collar distally with an inserter causes the spreader to expand the collar against the surrounding bone to secure the suture anchor in place. Such embodiments may also include a detachment or breakaway feature between the inserter and the suture anchor to permit separation after anchor deployment. Some embodiments of the present invention include methods for deploying such suture anchors and expanding the expandable collars and/or detaching the inserter tools. Embodiments of the present invention may be used in various orthopedic applications such as, for example, shoulder repair.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/261,480, filed on Nov. 16, 2009, and claims foreign priority to French Patent Application No. 1050965, filed on Feb. 11, 2010, both of which are incorporated by reference herein in their entireties for all purposes. 
    
    
     TECHNICAL FIELD 
     Embodiments of the present invention relate generally to suture anchors for bone implantation, and more specifically to suture anchors with multiple kinds of anchoring capabilities. 
     BACKGROUND 
     An orthopedic surgery may involve different kinds of repairs within the same procedure. For example, an operation to repair shoulder instability may include capsular shifts, labral reattachments, or some combination of the two activities. In some cases, a simple knotted suture anchor may provide a desired solution, while in other cases, a more elegant, knotless suture anchor may better accomplish the surgeon&#39;s purposes. Existing suture anchors for implantation into bone are typically either for use with knotted sutures or for use with a knotless suture anchoring technique, but not both. However, the particular suture anchoring requirements may not become apparent until after a surgical procedure has begun. 
     SUMMARY 
     Some embodiments of the present invention include a suture anchor with both knotless and knotted suture attachment capabilities, as well as methods for loading the suture in knotless and knotted configurations. Some embodiments of the present invention include a suture anchor with an inner implant body with an inverted wedge or spreader that slides in relation to an outer expandable collar, such that pushing the expandable collar distally with an inserter causes the spreader to expand the collar against the surrounding bone to secure the suture anchor in place. Such embodiments may also include a detachment or breakaway feature between the inserter and the suture anchor to permit separation after anchor deployment. Some embodiments of the present invention include methods for deploying such suture anchors and expanding the expandable collars and/or detaching the inserter tools. Embodiments of the present invention may be used in various orthopedic applications such as, for example, shoulder repair. 
     EXAMPLE 1 
     A suture anchoring system according to embodiments of the present invention includes an implant body extending substantially longitudinally from a proximal end to a distal end, the implant body including an insertion nose at the distal end, the insertion nose configured for insertion into bone, a slot formed in the implant body, the slot extending at least partially longitudinally, the slot having a slot proximal edge and a slot distal edge, and a slider that slides along the slot, the slider comprising a slider proximal edge and a slider distal edge, a first aperture at least partially formed by the slot distal edge and the slider distal edge, and a second aperture at least partially formed by the slot proximal edge and the slider proximal edge, the second aperture located proximally with respect to the first aperture, wherein the slider is configured to slide along the slot both before and after implantation of the implant body, such that a suture passed through only one of the first and second apertures before implantation is moveable freely in both directions after implantation, and such that a suture threaded, before implantation, through one of the first and second apertures, around the slider, and back through the other of the first and second apertures is, after implantation, moveable freely in a first direction but substantially inhibited from moving in a second direction opposite the first direction. 
     EXAMPLE 2 
     The suture anchoring system of Example 1, wherein when a suture is threaded through one of the first and second apertures, around the slider, and back through the other of the first and second apertures, the suture moves freely in the first direction, but is pinched between the slider and the slot when moved in the second direction. 
     EXAMPLE 3 
     The suture anchoring system of any of Examples 1 or 2, further including a collar slidably coupled with the implant body, the collar including one or more anchor fins, the collar slideable with respect to the implant body between at least an implant position in which the one or more anchor fins have a maximum lateral dimension smaller than or the same as that of the insertion nose, and a deployed position in which the maximum lateral dimension is larger than that of the insertion nose. 
     EXAMPLE 4 
     The suture anchoring system of any of Examples 1 to 3, wherein the implant body includes a spreader configured to move the one or more anchor fins between the implant position and the deployed position as the collar is slid with respect to the implant body. 
     EXAMPLE 5 
     The suture anchoring system of any of Examples 1 to 4, wherein a proximal end of the spreader is narrower than a distal end of the spreader, such that sliding the collar distally with respect to the implant body moves the collar from the implant position to the deployed position. 
     EXAMPLE 6 
     The suture anchoring system of any of Examples 1 to 5, urther including an inserter attachment coupled to the proximal end of the implant body with a break-away coupling. 
     EXAMPLE 7 
     The suture anchoring system of any of Examples 1 to 6, further including an inserter having an outer lateral dimension at its distal end that is smaller than or the same as that of the insertion nose, the inserter coupled to the inserter attachment in a manner which permits actuation of the inserter to slide the collar with respect to the implant body. 
     EXAMPLE 8 
     The suture anchoring system of any of Examples 1 to 7, wherein the inserter includes an outer shaft and an inner shaft, wherein the outer shaft slides with respect to the inner shaft, wherein the inner shaft is rigidly coupled to the inserter attachment, and wherein the outer shaft is configured to abut a proximal end of the collar. 
     EXAMPLE 9 
     The suture anchoring system of any of Examples 1 to 7, wherein the inserter includes an outer shaft configured to receive the inserter attachment, wherein the outer shaft slides with respect to inserter attachment. 
     EXAMPLE 10 
     The suture anchoring system of any of Examples 1 to 9, wherein the inserter is configured to decouple the inserter attachment from the proximal end of the implant body at the break-away coupling by moving the collar from the implant position to the deployed position. 
     EXAMPLE 11 
     The suture anchoring system of any of Examples 1 to 10, further including a loader which includes an inner cavity configured to receive the implant body (or alternatively, both the distal end of the inserter and the implant body), an outer surface, an opening formed in the loader, the opening extending from the outer surface to the inner cavity, wherein the opening has a first opening area at the outer surface and a second opening area at the inner cavity, the first opening area being larger than the second opening area, and an alignment feature, wherein the alignment feature is configured to align one of the first and second apertures with the second opening area when the distal end of the inserter and the implant body are received by the inner cavity. 
     EXAMPLE 12 
     The suture anchoring system of any of Examples 1 to 11, wherein the opening is a first opening, the loader further including a second opening formed in the loader, the second opening extending from the outer surface to the inner cavity, wherein the second opening has a third opening area at the outer surface and a fourth opening area at the inner cavity, the third opening area being larger than the fourth opening area, wherein the alignment feature is further configured to align the second opening area with the first aperture and the fourth opening area with the second aperture when the distal end of the inserter and the implant body are received by the inner cavity. 
     EXAMPLE 13 
     The suture anchoring system of any of Examples 1 to 12, wherein the first opening area is at least twice as large as the second opening area. 
     EXAMPLE 14 
     A method for suture anchoring according to embodiments of the present invention includes determining, before implanting a suture anchor, whether to employ knotless or knotted suture attachment using the suture anchor, and threading suture through the suture anchor of Example 1 based on the determination, and sliding the suture in at least one direction with respect to the suture anchor after implantation of the suture anchor. 
     EXAMPLE 15 
     The method of Example 14, wherein the determination is a determination to use knotless suture attachment, wherein threading the suture through the suture anchor further includes threading the suture through one of the first and second apertures, around the slider, and back through the other of the first and second apertures. 
     EXAMPLE 16 
     The method of any of Examples 14 and 15, further including passing the suture through a tissue to form a suture loop having two free ends, wherein threading the suture through the suture anchor further includes threading the two free ends through the one of the first and second apertures, around the slider, and back through the other of the first and second apertures. 
     EXAMPLE 17 
     The method of Example 14, wherein the determination is a determination to use knotted suture attachment, wherein threading the suture through the suture anchor further includes threading the suture through only one of the first and second apertures. 
     EXAMPLE 18 
     The method of any of Examples 14 and 17, further including passing the suture through a tissue to form a suture loop having two free ends, wherein threading the suture through the suture anchor further includes threading the two free ends through the only one of the first and second apertures. 
     EXAMPLE 19 
     The method of any one of Examples 14 to 18, wherein the suture anchor further includes a collar slidably coupled with the implant body, the collar including one or more anchor fins, the method further including sliding the collar with respect to the implant body between at least an implant position in which the one or more anchor fins have a maximum lateral dimension smaller than or the same as that of the insertion nose, and a deployed position in which the maximum lateral dimension is larger than that of the insertion nose. 
     EXAMPLE 20 
     The method of any one of Examples 14 to 19, wherein the suture anchor further includes an inserter attachment coupled to the proximal end of the implant body with a break-away coupling, the method further including decoupling the inserter attachment from the implant body at the break-away coupling. 
     EXAMPLE 21 
     The method of any one of Examples 14 to 20, wherein the suture anchor further includes an inserter having an outer lateral dimension at its distal end that is smaller than or the same as that of the insertion nose, the method further including actuating the inserter to slide the collar with respect to the implant body. 
     EXAMPLE 22 
     The method of any one of Examples 14 to 21, wherein the inserter includes an outer shaft and an inner shaft, wherein the inner shaft is rigidly coupled to the inserter attachment, wherein the outer shaft is configured to abut a proximal end of the collar, and wherein actuating the inserter includes pushing the collar distally relative to the implant body with the outer shaft while pulling the implant body proximally relative to the collar with the inner shaft. 
     EXAMPLE 23 
     The method of any one of Examples 14 to 22, wherein the suture anchor further includes the loader of Example 11, and wherein threading the suture through the at least one of the first and second apertures includes inserting the suture through the opening from the outer surface to the inner surface and then through the at least one of the first and second apertures. 
     While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a front perspective view of a suture anchor and inserter attachment, according to embodiments of the present invention. 
         FIG. 2  illustrates a front elevation view of the suture anchor and inserter attachment of  FIG. 1 , according to embodiments of the present invention. 
         FIG. 3  illustrates a front cross sectional view of a suture anchor and inserter during installation in a bone hole, according to embodiments of the present invention. 
         FIG. 4  illustrates a front cross sectional view of the suture anchor and inserter of  FIG. 3  after activation of the spreader, according to embodiments of the present invention. 
         FIG. 5  illustrates a front cross sectional view of the suture anchor of  FIGS. 3 and 4  after removal of the inserter, according to embodiments of the present invention. 
         FIG. 6  illustrates a side cross sectional view of a suture anchor, inserter, and loader, with a knotless suture configuration, according to embodiments of the present invention. 
         FIG. 7  illustrates a side cross sectional view of a suture anchor with a knotless suture configuration, according to embodiments of the present invention. 
         FIG. 8  illustrates a side cross sectional view of a suture anchor, inserter, and loader, with a knotted suture configuration, according to embodiments of the present invention. 
         FIG. 9  illustrates a side cross sectional view of a suture anchor with a knotted suture configuration, according to embodiments of the present invention. 
         FIG. 10  illustrates a method for manually loading a suture into a suture anchor in a knotless configuration without a loader device, according to embodiments of the present invention. 
         FIG. 11  illustrates a method for manually loading a suture into a suture anchor in a knotted configuration without a loader device, according to embodiments of the present invention. 
         FIG. 12  illustrates a variation of a slider plate suture anchoring system illustrating a knotless suture loading configuration, according to embodiments of the present invention. 
         FIG. 13  illustrates a variation of a slider plate suture anchoring system illustrating a knotted suture loading configuration, according to embodiments of the present invention. 
         FIG. 14  illustrates a variation of a slider plate suture anchoring system illustrating a knotless suture loading configuration, according to embodiments of the present invention. 
         FIG. 15  illustrates a variation of a slider plate suture anchoring system illustrating a knotted suture loading configuration, according to embodiments of the present invention. 
         FIG. 16  illustrates a slider plate used with a pressure fit anchor body, according to embodiments of the present invention. 
         FIG. 17  illustrates a threaded anchor body that turns independently of a slider mechanism, according to embodiments of the present invention. 
         FIG. 18  illustrates a slider mechanism included in an expanding collar assembly, according to embodiments of the present invention. 
         FIG. 19  illustrates an inserter coupled with a suture anchor implant and loader device, according to embodiments of the present invention. 
     
    
    
     While the invention is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION 
       FIGS. 1 and 2  illustrate a suture anchor  100  and inserter attachment  102  attached to the suture anchor  100 , according to embodiments of the present invention. The suture anchor  100  includes an expandable collar  107  which is connected to and slides with respect to an implant body  210 . The implant body  210  terminates at its distal end with a conical nose member  116  for insertion into a bone or a bone hole, according to embodiments of the present invention. The proximal end of the implant body  210  includes a spreader  106 , which is operatively attached to the inserter attachment  102  by a detachment or breakaway feature  104 , according to embodiments of the present invention. A slider  110  slides proximally and distally within, along, or across a notch  150  formed in the implant body  210 , between a distal edge  112  and a proximal edge  114  of the notch  150 , according to embodiments of the present invention. Notch  150  may also be referred to as slot  150 . Slot  150  is formed in the implant body  210  at least partially longitudinally; in other words, at least one component of the slot is in a longitudinal direction, wherein the longitudinal direction is the direction along the length of the implant between the proximal end  152  and distal end  152  of the implant body  210 . According to embodiments of the present invention, the implant body  210  includes the nose member  116 , the slot  150 , and the spreader  106  which are formed as a unitary assembly. According to some embodiments of the present invention, the implant body is constructed (e.g. molded) of a single continuous piece of material. 
     The spreader  106  is wider at its distal end near edge  114 , and narrower at its proximal end near detachment feature  104 ; this causes the collar  107  to spread or expand when the implant body  210  is moved in the direction indicated by arrow  212  with respect to the collar  107 , or when the collar  107  is moved in the direction indicated by arrow  214  with respect to the implant body  210 , according to embodiments of the present invention. The collar  107  includes a slot  119  which divides the collar  107  into halves and facilitates the expansion of the collar  107 . Each such half may be referred to as an anchor fin  108 . In  FIG. 2 , the fins  108  are depicted in the non-deployed state, while the deployed state of fins is illustrated in dashed lines at reference number  108 ′. In addition to the spreader  106  sliding proximally with respect to the fins  108  to spread the fins  108 , the rest of the implant body  210  also slides proximally with respect to the collar  107  until the bottom  202  of the collar  107  contacts or nears the top of the nose member  116 , according to embodiments of the present invention. According to embodiments of the present invention, the furthest proximal extent of the implant body  210  and spreader  106  is limited by the abutment of the bottom edge  202  of collar  107  with the top edge  204  of the nose member  116 . According to embodiments of the present invention, the slider  110  is configured to slide along the slot  150  both before and after implantation of the suture anchoring system  100 . 
     Collar  107  is slidably coupled with the implant body  210 , the collar  107  includes one or more anchor fins  108 , the collar  107  is slideable with respect to the implant body  210  between at least an implant position (as illustrated in solid lines in  FIG. 2 ) in which the one or more anchor fins have a maximum lateral dimension D 1  smaller than or the same as that of the insertion nose  116 , and deployed position (illustrated partially in phantom lines in  FIG. 2 ) in which the maximum lateral dimension D 2  is larger than that of the insertion nose  116 , according to embodiments of the present invention. 
       FIGS. 3 through 5  illustrate a method for installing or implanting the anchor  100 , according to embodiments of the present invention. The inserter attachment  102  attaches the implant body  210  with the inserter  101 . The inserter  101  has an outer lateral dimension at its distal end  103  that is smaller than or the same as that of the insertion nose, the inserter  101  coupled to the inserter attachment  102  in a manner which permits actuation of the inserter  101  to slide the collar  107  with respect to the implant body  210 . First, the suture anchor  100 , which is attached to the inserter  101  via the inserter attachment  102 , is placed within a hole  304  in the bone  302 . In the non-deployed state, the anchor  100  and inserter  101  and fins  108  may be of a substantially uniform diameter and/or cylindrical shape to easily fit within the hole  304 , as illustrated in  FIG. 3 , according to embodiments of the present invention. In some embodiments of the present invention, the hole  304  is pre-drilled. The inserter  101  may include a substantially hollow tube  132  at its distal end which contains and/or holds within it the inserter attachment  102 , according to embodiments of the present invention. 
     According to some embodiments of the present invention, the inserter  101  comprises an outer shaft  132  and an inner shaft  134 , wherein the outer shaft  132  slides with respect to the inner shaft  134 , wherein the inner shaft  134  is rigidly coupled to the inserter attachment  102 , and wherein the outer shaft  132  is configured to abut a proximal end  111  of the collar  107 . According to other embodiments of the present invention, the inserter  101  comprises an outer shaft  132  only, which is configured to receive the inserter attachment  102 , wherein the outer shaft  132  slides with respect to inserter attachment  102 . 
     Once the anchor  100  and inserter  101  are placed within the bone hole  304 , the inserter  101  is pushed in a distal direction, thereby permitting the distal end of the inserter  101  to contact the top of the collar  107 . As illustrated in  FIG. 4 , continuing to push down on the collar  107  with inserter  101  and/or impulsing the inserter  101  onto the collar  107  causes the collar  107  to move in a distal direction with respect to the implant body  210 , which causes the spreader  106  to expand or spread the fins  108  outwardly to engage the surrounding bone  302 , according to embodiments of the present invention. Once the fins  108  of the collar  107  have been expanded, firmly engaging the suture anchor  100  with the surrounding bone  302 , the inserter  101  may be pulled in a proximal direction to break the connection between the inserter  101  and inserter attachment  102  at detachment feature  104 , as illustrated in  FIG. 5 , thus leaving the spreader  106  implanted in the bone  302 . The inserter  101  and inserter attachment  102  may be connected in a way that permits the inserter  101  to slide distally over the inserter attachment  102 , but which does not permit the inserter attachment  102  to fall out or off of the inserter  101  after the inserter attachment is broken from the spreader  106  at detachment feature  104 , according to embodiments of the present invention. 
     According to some embodiments of the present invention, the inserter attachment  102  is detached at the detachment feature  104  while the inserter  101  is being pushed against the collar  107 , rather than afterward. According to other embodiments of the present invention, the outer tube of the inserter  101  includes inwardly projecting teeth which slide easily over the detachment feature  104  in the distal direction, but which securely grasp the inserter attachment  102  at the detachment feature  104  when slid back in the proximal direction, thereby also retaining the inserter attachment  102  within the inserter  101  after the inserter attachment  102  has broken off at breakaway feature  104 . 
     Although the detachment feature  104  is depicted as a set of notches on both sides of the inserter attachment  102 , one of ordinary skill in the art will appreciate, based on the present disclosure, the structural weaknesses and/or various mechanisms that may be used to impart a breakaway or detachment performance at detachment feature  104  location. For example, the inserter attachment  102  may be connected to the spreader  106  at detachment feature  104  by a weak adhesive connection, a twisted connection, a twist-off connection, a precut connection, a perforated connection, a string connection, and/or the like, such that a force or action required to detach the inserter attachment  102  from the spreader  106  does not disturb or disengage the suture anchor  100 . 
     The inserter  101  and/or insertion attachment  102  may also include graduations or other markings or registrations to assist the surgeon in achieving or evaluating the position and/or depth of the suture anchor  100 , according to embodiments of the present invention. 
     Prior to anchoring within bone  302 , the suture anchor  100  may be loaded with suture in either a knotless fashion or a knotted fashion, according to embodiments of the present invention.  FIGS. 6 and 7  illustrate loading of the suture anchor  100  in a knotless fashion. The suture illustrated in  FIG. 6  is a double suture, or loop, having a looped end  614  and a pair of suture tails  612  at the other end, according to embodiments of the present invention. The looped end  614  may be looped through and/or attached to tissue or some other material that the surgeon will secure and/or place in tension with the suture, according to embodiments of the present invention. 
     The suture anchor  100  includes two apertures at least partially formed by the slider  110 . As shown in  FIG. 2 , a first aperture  230  is formed at least partially by the distal end  112  of the notch in the implant body  210  and the distal (or bottom) end  208  of the slider  110 . A second aperture  232  is formed at least partially by the proximal (or top) end  206  of the slider  110  and the proximal (or top) end  114  of the notch in the implant body  210 , which is also the distal (or bottom) end  114  of the spreader  106 , according to embodiments of the present invention. 
       FIG. 6  illustrates the suture anchor  100  within a loader device  602  which facilitates loading the suture through apertures  230 ,  232  in the suture anchor  100 .  FIG. 17  also illustrates an inserter  101  with a loader  602  and implant  100  therein. A device like loader  602  reduces the time necessary to perform a given operation. The device  602  includes openings  604 ,  608  larger than the apertures  230 ,  232  in the suture anchor  100 , to facilitate threading or loading of the suture through the suture anchor  100 . The suture tails  612  are first placed through opening  604  in the loader  602 , which narrows in size similar to a funnel and aligns with aperture  230  to pass the suture through the aperture  230  and out of the opening  606  on the other side of loader  602 . The suture tails  612  are then placed through opening  608 , which narrows in size and aligns with aperture  232  to pass the suture through the aperture  232  and out of opening  610  on the other side of loader  602 . The loader  602  may then be removed from the suture anchor  100  and inserter  101 , while leaving the suture threaded through apertures  230 ,  232 . According to embodiments of the present invention, the loader  602  has two corresponding halves that open at a hinge, or that removably snap-fit together. 
     The loader  602  includes an inner cavity  616  configured to receive the distal end of the inserter  101  and the implant body  210 , an outer surface  618 , an opening  604  formed in the loader  602 , the opening  604  extending from the outer surface  618  to the inner cavity  616 , wherein the opening  604  has a first opening area  620  at the outer surface  618  and a second opening area  622  at the inner cavity  616 , the first opening area  620  being larger than the second opening area  622 , according to embodiments of the present invention. According to embodiments of the present invention, the area A 1  of the first opening area  620  is at least twice as large as the area A 2  of the second opening area  622 . The loader  602  may also include an alignment feature configured to align one of the first and second apertures  230 ,  232  with the second opening area  622  when the distal end of the inserter  101  and the implant body  210  are received by the inner cavity  616 . For example, one or more pin or ball members  624  may serve as alignment features, by interfacing with a slot on the implant body  210  or between implant body  210  and collar  107 , to ensure that the position and orientation of the distal end of the inserter  101  and implant body  210  are known when received by the loader  602 . For example, the alignment feature is a feature which aligns the first aperture  230  with the second opening area  622  when the anchor  100  is received by the loader  602 , to permit easy threading of suture therethrough. Opening  608  may have characteristics similar to those of opening  604 , according to embodiments of the present invention, but may be formed from an opposite side of the outer surface  618  as illustrated in  FIG. 6 . 
       FIG. 7  illustrates the suture anchor  100  after the suture has been loaded in a knotless configuration. If looped end  614  is connected to tissue and the suture anchor  100  is inserted within a bone hole and expanded as described with respect to  FIGS. 3-5 , the ends  612  may be pulled by the surgeon to tighten the tension on end  614 . The tension on end  614  pushes the slider  110  in the direction indicated by arrow  702 , which pinches or “cinches” or otherwise holds the suture between edge  114  of the implant body  210  and edge  206  of the slider  110 , according to embodiments of the present invention. According to embodiments of the present invention, the harder the surgeon pulls ends  612 , the tighter the suture is held between the slider  110  and the spreader  106 . The slider  110  thus operates to permit the suture to slide through the suture anchor  100  when ends  612  are pulled in direction  704 , while also prohibiting movement of the suture toward end  614  in direction  706 , thereby inhibiting an unintended loosening of the tension on the tissue side  614  of the suture. 
     Although  FIGS. 6 and 7  illustrate a suture loop, one of ordinary skill the art, based on the disclosure presented herein, will appreciate that the knotless configuration illustrated and described may similarly be achieved with multiple suture loops and/or a single non-looped suture strand, according to embodiments of the present invention. A suture loop may be loaded through the anchor  100  in the knotless configuration either before or after the suture has been passed through tissue, according to embodiments of the present invention. This knotless suture path also permits the surgeon to successively and selectively tighten the tension on end  614 ; for example, the surgeon may place a smaller amount of tension on end  614  by pulling suture tails  612  of the suture loop in direction  704 , this smaller amount of tension being maintained by the locking mechanism of pinching between the slider  110  and the slot  150 , and the surgeon may return later in the operation to add further tension to the end  614  by further pulling suture tails  612  in direction  704 , and this may all be accomplished after implantation of the anchor  100 . 
       FIGS. 8 and 9  illustrate a loading of the suture anchor  100  for a knotted deployment. One end of the suture  802  may be attached to tissue or other material, and the other end  804  of the suture may be placed through opening  604 , through aperture  230 , and out of opening  606 . The suture anchor  100  with the suture in a knotted configuration is illustrated in  FIG. 9 . The suture is able to slide freely back and forth through aperture  230 , and may be placed through tissue or other material and knotted; for example, the two ends  802 ,  804  may be knotted together, according to embodiments of the present invention. 
     Although a single suture strand is illustrated, one of ordinary skill in the art, based on the present disclosure, will appreciate that multiple suture strands and/or looped suture strands may be loaded into the suture anchor  100  in a knotted configuration, according to embodiments of the present invention. According to an alternative embodiment of the present invention, loading the suture through the suture anchor  100  in a knotted configuration includes threading the suture through aperture  232  instead of aperture  230 . According to embodiments of the present invention, the tension forces on the suture, in either the knotted or the knotless configurations, pull the implant body  210  proximally with respect to the collar  107 , which serves to enhance and maintain the expansion of the collar  107  within the bone hole  304 , promoting the continued secure anchoring of suture anchor  100  within bone hole  304 . 
     Although the loader  602  is illustrated as being usable to load suture into the anchor  100  of  FIGS. 1 and 2 , different loaders  602  may have different dimensions in order to accommodate various different kinds of suture anchors having apertures formed by a slot and a slider. For example, a similar loader  602  may be used to facilitate loading of suture through the apertures of the anchors or locking mechanisms of  FIGS. 12-18 , with each loader having an inner cavity  614  sized to accept a particular anchor. Openings  604 ,  608  of the loader  602  may be substantially parallel to each other, may be separated by walls within the loader  602 , and may have a circular, oval, rectangular, or other cross sectional shape, according to embodiments of the present invention. Openings  604 ,  608  facilitate suture passage, with or without a needle, according to embodiments of the present invention. According to some embodiments of the present invention, the inner cavity  614  has variable dimensions adapted to different implant models, which present varying dimensions. The loader  602  may have deformable and/or elastomeric walls which adapt to implants having different diameters, according to embodiments of the present invention. 
     In comparing  FIGS. 7 and 9 , because the slider  110  is configured to slide along the slot  150  both before and after implantation of the implant body  210 , a suture passed through only one of the first and second apertures  230 ,  232  before implantation (see  FIG. 9 ) is moveable freely in both directions  808 ,  810  (e.g. the suture travel directions achieved by pulling on either end of the suture) after implantation; while a suture threaded, before implantation, through one of the first and second apertures  230 , around the slider  110 , and back through the other of the first and second apertures  232  (see  FIG. 7 ) is, after implantation, moveable freely in a first direction  704  but substantially inhibited from moving in a second direction  706  opposite the first direction. This inhibition of suture movement is caused in the knotless configuration because as end  614  is tensioned, the tension essentially applies an upward force to slider  110 , which, in turn, pinches the suture between slider  110  and the upper edge of slot  150 , according to embodiments of the present invention. 
     Although a loader device  602  is illustrated for facilitating the loading or threading of the suture through one or more apertures  230 ,  232 , one of ordinary skill in the art, based on the present disclosure, will appreciate that such loading may be accomplished by hand, without the assistance of a loader device, as illustrated in  FIGS. 10 and 11 . 
     And although a slider  110  mechanism is illustrated, one of ordinary skill in the art, based on the present disclosure, will appreciate that other pinching or cinching mechanisms may be employed to secure the suture in the knotless configuration while also permitting threading of the suture in the knotted configuration, for example the cinch ring configuration illustrated in  FIGS. 12 and 13  or the fixed eyelet and cross-piece configuration illustrated in  FIGS. 14 and 15 . In the ring cinch configuration of  FIGS. 12 and 13 , the longitudinal slot is formed by one ring  1202 , and the other ring  1204  operates as a slider. In some embodiments, one of the rings  1202 ,  1204  may be rigidly coupled with the implant body, such as implant body  250 ; in other embodiments, both rings  1202 ,  1204  slide independently of one another and of the implant body. Sutures may be selectively threaded through apertures  1206 ,  1208  in a knotless configuration (as illustrated in  FIG. 12 ), or in a knotted configuration (as illustrated in  FIGS. 13 ). In the configuration of  FIGS. 14 and 15 , the longitudinal element  1402  has a longitudinal slot formed therein, and the slider ring  1404  slides along element  1402  to separate the longitudinal slot into a first aperture  1406  and a second aperture  1408 , which may be threaded in the knotless configuration (as illustrated in  FIG. 14 ) or in the knotted configuration (as illustrated in  FIG. 15 ), according to embodiments of the present invention. In either of the embodiments of  FIGS. 12-15 , the distal loop pulls upwardly against one of the two interacting elements to pinch or squeeze the suture between such element and the other element. 
     A similar slider mechanism  110  may also be used with other implant bone fixation mechanisms; for example, a slider  1402  within a pressure fit fixation anchor body  1404  as illustrated in  FIG. 16 , or a slider  1502  within a fixture  1504  mounted within an outer anchor body  1506  with one or more threads  1508  which turns independently of the fixture  1504  and/or slider  1502  as illustrated in  FIG. 17 , or a slider  1602  within an expanding collar assembly as illustrated in  FIG. 18 , according to embodiments of the present invention. In each of these embodiments, the slider  1402 ,  1502 ,  1602  creates a proximal aperture and a distal aperture, and the free end of the suture may be loaded through the distal aperture and then through the proximal aperture to impart knotless performance, and can be loaded through the distal aperture only (or, alternatively, through the proximal aperture only) to impart knotted capability, according to embodiments of the present invention. 
       FIG. 19  illustrates an inserter  101 , according to embodiments of the present invention. A loader  602  is mounted on a distal end of the inserter  101 , and the proximal end of the inserter  101  comprises a knob or handle  1901  which, along with the inserter shaft  1902 , may be used by the surgeon to position, insert, and/or manipulate the implant  100  into the bone  320 . The knob  1901  is adapted to include a grip that is practical and comfortable for the surgeon. 
     Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.