Method and apparatus for attaching connective tissues to bone using a knotless suture anchoring device

Abstract
An innovative bone anchor and methods for securing soft tissue, such as tendons, to bone are described herein Such devices and methods permit a suture attachment that lies beneath the cortical bone surface and does not require tying of knots in the suture.
Description

BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1A illustrates a partial view of the shoulder anatomy in which the humerus is adjacent to the rotator cuff and labrum as it nests within against the glenoid and anchors placed in the labrum in accordance with the invention;



FIG. 1B is another view of a suture within the labrum and adjacent to a cavity created in the bone but where the suture is yet to be coupled to an anchor;



FIG. 2A shows a view of the anchor and suture in a deployed configuration;



FIG. 2B shows a cross sectional view of the anchor as it compresses a section of the suture within the anchor;



FIGS. 2C and 2D show a variation of anchor components;



FIG. 3A illustrates a perspective view of a variation of an anchoring system as described herein;



FIGS. 3B and 3C show a distal end of the anchoring system with a snare and suture respectively;



FIGS. 4A-4B show a perspective view and cross sectional view respectively prior to compressing a suture within the anchor;



FIGS. 4C-4D show a perspective view and cross sectional view respectively after the components of the anchor are joined to retain a suture therein; and



FIG. 4E shows a partial sectional view of an anchor placed within a cavity and attached to soft tissue.





DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention provides improved methods and devices for knotless suturing of tissue. Although the variation discussed herein discusses use of a suture, the term “suture” may include any piece of material that is used to close a wound or connect tissue (e.g., catgut, thread, wire, etc.) so long as the material can be used with the other portions of the anchor as described herein. Accordingly, sutures as described herein may include polymeric, metallic, or other types of sutures.


For illustrative purposes, the examples discussed herein show the use of the anchoring system to suture soft tissue to a bone structure, specifically the soft labrum to the glenoid. In one variation of the system, the medical practitioner affixes a length of suture through soft tissue to approximate and fix the soft tissue with respect to the body cavity (e.g., a bored hole in the bone structure). It should be understood, however, that the suture anchor apparatus may be utilized to secure a length of suture to body cavities other than in a bone structure, and may even be used to anchor the suture outside of a body cavity, merely to a predetermined location within the body.


In the suturing system described herein, the medical practitioner affixes the suture to an anchor body that is placed in the body cavity. The design of the system eliminates the needs for knotting of the suture. However, the present system also allows tying of an end of the suture into a knot if the practitioner so desires.


The invention permits minimally invasive surgeries on injuries and greatly facilitates rapid and secure fixation of the target tissues. It should be understood that the same principles described herein apply to the repair of other injuries in which soft tissue is to be re-attached to a bone structure.



FIG. 1A illustrates a partial view of the shoulder anatomy 10 in which the humerus 14 is adjacent to the rotator cuff 12 and labrum 18 as it nests within against the glenoid 20. The scapula 16 is partially shown. For clarity, various bones and other soft tissue are not illustrated in FIG. 1A.



FIG. 1A also illustrates exemplary placement of anchors 100 according to the system described herein. As shown, the anchor 100 secures soft tissue (e.g., the labrum) to hard tissue (e.g., the glenoid) via a suture 102. Any number of anchors 100 may be employed. Moreover, the location of the anchors and sutures may vary as required. As shown, the anchor body 104 is located within a cavity in the bone. This cavity is created prior to affixing the anchor within the bone.



FIG. 1B shows a view of a single suture 102 adjacent to a cavity 22 created in the bone. At this point, the free ends 108 of the suture 102 do not enter the cavity but are directed towards the anchoring system (not shown) as described in further detail below. FIG. 1B illustrates placement of the suture 102 within the labrum 18. In this example, a looping 106 section secures the suture 102 to the labrum 18. The looping section 106 may extend through the tissue so that both free ends 108 of the suture 102 can be loaded into the anchor (not illustrated in FIG. 1B).


Typically, the soft tissue is grasped or stabilized using a device while needles place a stitch in the tissue. An example of a device capable of placing the suture is the SPEED STITCH™ Suturing device provided by ArthroCare, Sunnyvale Calif. However, the methods and devices described herein are not limited to such a technique. For example, a single end of the suture may be affixed to soft tissue such that the other free end of the suture is eventually affixed to the bone via the anchor.


The hole or cavity 22 sites are planned by applying traction to the suture. This action allows the practitioner to estimate the proximity of the holes to the labrum. Typically, the holes 22 are created 2 mm from the glenoid rim onto the articular surface of the glenoid. However, in certain cases, the holes 22 may be created on the glenoid rim.



FIG. 2A illustrates an example of a deployed anchor 100 having a suture 102. As shown, the anchor 100 includes an anchor body 104 that seats a locking plug 110. FIG. 2B shows a cross-sectional view of the anchor 100 of FIG. 2A. As discussed herein, a first section 124 of the suture 102 becomes secured within the anchor 100 while a second section 126 wedges between the cavity wall (not shown) and an exterior of the anchor body 104. In this variation, the suture 102 loops from a first side of the anchor to a second side via a suture opening 120 located in a stop portion 112 of the locking plug 110.



FIG. 2C illustrates an example of a locking plug 110. The locking plug 110 includes a shaft 114 intended to nest within the anchor body. The locking plug 110 also includes a stop portion 112 that limits movement of the plug 110 within the anchor body. Although the shaft portion 114 is illustrated as being smooth and cylindrical, the devices described herein include various additional combinations of shapes and textures or surfaces on the shaft. In particular, the surface of the shaft 114 may be configured to increase the frictional force applied by the anchor against the suture portion held therein. In addition, the suture opening 120 is illustrated as an opening within the stop portion 112. However, other shapes and locations of the suture holder 120 may be incorporated into the anchor. For example, the suture opening 120 may not be fully surrounded by the stop portion 112 (e.g., a groove in the face of the stop portion). Alternatively or in combination, the suture opening 120 may be located in the shaft portion 114 of the locking plug 110.


Turning back to FIG. 2B, the shaft 114 of the locking plug 110 may include a section allowing for a removable connection with the anchor system 150. In this variation, the removable connection comprises an internal threaded portion 118 within the shaft. As discussed herein, in one variation, upon application of sufficient stress between the mating threaded portions, one or both of the threaded portions strip to allow for a release of the anchor 100 from the system 150. In additional variations, other removable connections as commonly known by those skilled in the art are contemplated to be within the scope of the invention.



FIG. 2D illustrates an example of an anchor body 104. As shown, the anchor body includes a lumen 122 that is sufficiently sized to permit passage of the locking plug shaft 114. In addition, this variation of the anchor body 114 is non-deformable or rigid and includes a plurality of tapered ridges 116 or anchoring structures that deform the tissue upon placement of the anchor into the body cavity. As shown, the tapering shape of the ridges 116 allow for insertion of the anchor body into the cavity when inserted in a first direction and resist removal when the anchor body is urged in an opposite direction. The illustration of the ridges 116 is intended for example only. Variations are within the scope of the device and methods described herein. For example, variations include anchoring structures that do not fully encircle the anchor body. In additional versions of the device, the anchor body may be slightly deformable such that it at least partially conforms to the body cavity.



FIG. 3A illustrates a variation of the suture anchoring system 150 as described with an anchor located in the distal portion of the system 150. As shown, a snare 152 is placed within the anchor to allow the medical practitioner to load a suture for securing tissue. A removable snare body holder 156 can be used to prevent the snare 152 from becoming damaged or from disengaging the anchor during, for example, handling and shipment. The system 150 includes an extension member 170 extending from a handle portion 172. The distal end of the extension member 170 includes an anchor seat 166 while a rod (not shown) is located within the extension member 170. In use, the rod is moveable relative to the anchor seat 166 to assist in deploying or disengaging the anchor from the system 150.


In the embodiment shown in FIG. 3A, the handle portion 172 includes a wheel or spool member 174. The spool member may have one or more knobs 176 associated with it that allow for tensioning of the suture for tissue approximation. In this particular variation, a spool 178 allows for retraction of the snare 158. As the wheel is rotated, the snare and suture may be drawn through the system 150. The spool member 174 may also include a locking mechanism 180 (such as the locking ratchet configuration shown) to prevent undesired movement (e.g., back out) of the suture and/or snare. The handle portion 172 may also include a lever 182 that moves the inner rod relative to the extension member 170 and anchor seat 166. In this variation the lever 182 comprises a rotational lever or cam. As discussed below, using the lever to advance an anchor body against a stop portion on the locking plug ultimately disengages the anchor from the system 150.



FIG. 3B illustrates a distal end of the suture anchoring system 150 according to the present devices and methods. To load the suture 102 in the anchoring system 150, the medical practitioner passes the free end or ends 108 of the suture 102 into a snare 152. The snare 152 extends through the anchor 100 and anchoring system and can be coupled to the spool member (not shown). In the variation shown, the snare 152 comprises a wire terminating in a loop 154 as shown. Alternatively, the snare 152 may have any other means of permanently or temporarily securing the suture 102 so that it may be passed into the anchoring system (e.g., clamps, hooks, sleeves, etc.). Moreover, it is not necessary to capture the ends of the suture 102. Instead, the practitioner may extend the suture beyond the loop.


Next, the medical practitioner draws the suture 102 through the anchor 100 and into the anchoring system 150 (for example, via activation of the spool member). The result is shown in FIG. 3C, which shows the suture 102 extending through a portion 112 of a locking plug 110 to pass from a first side of the anchor 100 to an adjacent side through the suture carrying portion 120 of the locking plug 110. Ultimately, the suture 102 passes through the anchor body 104. This configuration allows loading of the suture 102 into the interior lumen of the anchor body 104. Although not illustrated, the suture 102 can be withdrawn into a handle portion of the device for tensioning prior to placement.



FIG. 4A illustrates the assembly after the medical practitioner removes the snare body holder 156 so that the assembly is ready for insertion into a body cavity 22. At this point, the medical practitioner can adjust the tension in the suture 102 by adjusting the suture 102 length between the section of the suture that is placed in tissue (not shown but designated by 106) and the locking plug 110. As described herein, the adjustment may be performed using the spool assembly or a similar tensioning system. As discussed herein, a first section 124 of the suture 102 is situated so that it remains inside the deployed anchor 100.



FIG. 4B illustrates a cross sectional view of the device of FIG. 4A. In this view the suture is omitted for clarity. As illustrated, the shaft 114 of the locking plug 110 includes a threaded portion 118 that receives a threaded rod portion 168. As noted herein, the devices and methods include various configurations for removably connecting the shaft 114 to the rod 160 other than threading. For example, a frictional press-fit or barbed coupling may be employed.



FIG. 4C illustrates the anchor 100 upon deployment but before it is disengaged from the system 150 and anchor seat 166. As shown, the anchor body 104 slides over the shaft 114 of the locking plug 110 to trap the first section (not shown) of the suture 102 within the anchor body 104. In some variations, the first section 124 of the suture 102 may be withdrawn into the system 170 as the anchor body 104 advances onto the shaft 114 of the plug 110. Ultimately, the stop portion 112 of the locking plug 110 contacts the anchor body 104.


In this variation of the invention, the body is urged over the shaft of the plug by first, rotating ninety (90) degrees a flag 282 and button 284. The button 284 and flag 282 are used to lockout (prevent relative movement between the anchor and plug) during the initial placement of the anchor into the bone passage. Next, the surgeon pushes or taps on the button 284 which drives body 104 onto plug 110. While the anchor body is being urged onto the plug, internal ratchet teeth ensure that the members 140/166/170 can not back out between taps. When the button 284 is flush with the back of member 182, body 104 is pushed all the way onto the shaft 114 and the suture is locked.


In one embodiment of the invention, the operator may further tension the suture (approximate tissue) by urging or pounding the anchor into the hole by continuing to tap on the button. This action will serve to urge the anchor, with suture attached, deeper into the hole thus dragging the tissue.


Referring again to FIGS. 3A and 4D to separate the anchor from anchor seat 166, the rotating lever knob 182 is twisted to push seat 166 further into plug 110 which ultimately strips the rod 168 out of member 118. A driver block (not shown) simultaneously releases the suture ratchet reel 174 so the suture can pay out as the inserter is being removed. This is accomplished by the driver block actuating a stop 286 proximal to spool 174.



FIG. 4E shows a deployed anchor 100 situated within the body cavity 22 after release from the anchoring system 150. As shown, the anchor body 104 compresses a second section 124 of the suture 102 against a wall of the cavity 22. The first section of the suture 102 remains within the anchor between the locking plug 110 and interior of the anchor body 104.


Although the variation depicts the portion of the anchor as being adjacent to the surface of the hard tissue, variations of the method and device include anchors that are deployed partially above or fully below the surface of the tissue. As shown, the anchor body 104 impinges a second section 124 of the suture against a wall of the cavity 22. Accordingly, the act of inserting the anchor body 104 into the cavity 22 actually increases the tension on the soft tissue since the anchor body 104 further drives the second suture section 124 into the cavity 22 during placement.


Another variation of a method for deploying the anchor includes advancing the anchor body 104 over the shaft 114 when the assembly is located within the cavity. For example, the locking plug 110 may be inserted into the cavity prior to advancement of the anchor body 104 onto the shaft 114 (as shown by the configuration of FIG. 4A). Next, the medical practitioner can adjust the tension on the suture 102 until a desired length of suture extends from the cavity to the soft tissue. Finally, the medical practitioner advances the anchor body 104 into the cavity. At the same time, the anchor advances over the locking plug shaft 114. This action produces the configuration shown in FIG. 4C. Again, the action of the anchor body 104 serves to further secure the soft tissue as the anchor body 104 drives the second section 124 of the suture 102 further into the cavity and ultimately deploys the anchor as shown in FIG. 4E.


The amount of force required to separate the anchor from the deployment system is sufficiently high to minimize inadvertent deployment but also to ensure that the surgeon can deploy the anchor as desired.


One advantage provided by the present invention is the ability to tighten a suture loop embedded within soft tissue to a predetermined tension, and lock the suture within a suture anchor without losing that tension.


Accordingly, although an exemplary embodiment of the invention has been shown and described, it is to be understood that all the terms used herein are descriptive rather than limiting, and that many changes, modifications, and substitutions may be made by one having ordinary skill in the art without departing from the spirit and scope of the invention. In particular, it is noted that the procedures, while oriented toward the arthroscopic repair of the rotator cuff, are applicable to the repair of any body location wherein it is desired to attach or reattach soft tissue to bone, particularly using an arthroscopic procedure.

Claims
  • 1. A knotless suture anchoring system for anchoring a length of suture with respect to a body cavity, comprising: an anchor body having at least one rigid anchoring structure allowing for securing the anchor body within the body cavity, the anchor body having a proximal end, a distal end, and a lumen extending therebetween;a locking plug slidably coupled to the distal end of the anchor body and having a distal stop and a shaft portion, the distal stop being sized to prevent entry into the anchor body lumen, where the shaft portion is sized relative to the anchor body lumen to allow movement therein when no suture is located within the anchor body lumen and a friction fit when the suture is located in the anchor body lumen;a suture carrying portion in the distal stop allowing the suture to pass from a first side of the locking plug to an opposite side of the locking plug; anda snare extending through anchor body lumen and the suture carrying portion such that when the distal portion of the snare is affixed to the suture, withdrawal of the snare pulls the suture through the suture carrying portion and the anchor body lumen.
  • 2. The system of claim 1, where the anchor body is generally tubular and has a plurality of ridges circumferentially located about the anchor body.
  • 3. The system of claim 2, where the ridges are tapered to permit insertion of the anchor body into the body cavity when advanced in a first direction and resist removal of the anchor body when withdrawn in an opposite direction.
  • 4. The system of claim 1, where the locking plug shaft is smooth.
  • 5. The system of claim 1, further where the snare comprises a wire and the distal end of the snare comprises a loop.
  • 6. The system of claim 1, further comprising a snare body, where the snare body secures the snare to the anchor system.
  • 7. The system of claim 1, further including a rod portion removably attached to a proximal end of the shaft and projecting through the anchor body lumen, the rod portion having an anchor seat adjacent to the anchor body and configured to allow movement of the anchor body relative to the shaft, such that relative movement between the anchor seat and the rod portion causes the anchor body to seat over the shaft.
  • 8. The system of claim 7, where the rod portion is removably coupled to an actuation assembly having a handle portion.
  • 9. The system of claim 8, where the actuation assembly further comprises a spool member coupled to the snare, such that actuation of the spool member causes withdrawal of the snare through the actuation assembly to feed the suture into the spool member allowing for tensioning of the suture with the spool member.
  • 10. The system of claim 8, where the actuation assembly further comprises a lever coupled to the anchor seat, such that activation of the lever causes advancement of the anchor seat and anchor body over the locking plug shaft.
  • 11. The system of claim 7, where the rod comprises an opening adjacent to an internal bore, where the opening permits passage of the suture through the bore and ultimately through the anchor body lumen.
  • 12. The system of claim 11, further where the snare extends through the internal bore of the rod through the opening.
  • 13. The system of claim 7, further including a section of tensile weakness along the rod permitting the rod to be detached from the shaft upon application of a predetermined tensile force on the rod in the proximal direction after the distal stop contacts the anchor body.
  • 14. The system of claim 7, further including an internal threaded portion in the shaft mating with an external threaded portion on the rod, such that a predetermined tensile force on the rod in the proximal direction after the distal stop contacts the anchor body causes stripping of the external threaded portion on the rod to detach the rod from the shaft.
  • 15. A knotless suture anchoring system, comprising: a suture having a tissue engaging portion, an anchoring portion and a mid portion therebetween;an anchor body having at least one rigid anchoring structure allowing for securing the anchor body within the body cavity, the anchor body having a proximal end, a distal end, and a lumen extending therebetween;a locking plug having a distal stop and a shaft portion at least partially located within the anchor body lumen, the distal stop being sized to prevent entry into the anchor body lumen, where the shaft portion is under sized relative to the anchor body lumen;a suture carrying portion associated with one of the distal stop or shaft portion allowing the suture to pass from a first side of the locking plug to an opposite side of the locking plug;where the tissue engaging portion extends externally to the anchor body, the anchoring portion extends within the anchor body lumen, and where the mid portion extends in the suture carrying portion.
  • 16. The system of claim 15, where the anchor body is generally tubular and has a plurality of ridges circumferentially located about the anchor body.
  • 17. The system of claim 16, where the ridges are tapered to permit insertion of the anchor body into the body cavity when advanced in a first direction and resist removal of the anchor body when withdrawn in an opposite direction.
  • 18. The system of claim 15, where the locking plug shaft is smooth.
  • 19. A method of securing soft tissue with respect to a body cavity without knots, comprising: passing a length of suture through soft tissue so that a portion of the suture is secured in the soft tissue resulting in at least one free end;providing an anchor comprising an anchor body having a lumen extending therethrough, and a locking plug having a shaft portion extending at least partially in the anchor body lumen;passing the free end of the suture into the anchor such that a first section of the suture is in a portion of the locking plug and extends through the anchor body lumen;applying tension to the suture between the tissue and the anchor; andinserting the anchor into the body cavity, such that a second section of the suture is between the anchor body and a wall of the body cavity.
  • 20. The method of claim 19, further comprising actuating the anchor within the body cavity so that the locking plug shaft portion seats in the anchor body lumen such that the first section of the suture is compress between the locking plug shaft portion and the interior of the anchor body lumen.
  • 21. The method of claim 20, where actuating the anchor comprises withdrawing the locking plug shaft into the anchor body lumen.
  • 22. The method of claim 20, where actuating the anchor comprises advancing the anchor body over the locking plug shaft.
  • 23. The method of claim 20, where the anchor is coupled a rod.
  • 24. The method of claim 23, where the rod is removably attached to a proximal end of the anchor shaft and projects through the anchor body lumen, the rod having an anchor seat adjacent to the anchor body and configured to allow movement of the anchor body relative to the shaft, such that relative movement between the anchor seat and the rod portion causes the anchor body to seat over the shaft.
  • 25. The method of claim 23, where the rod is removably coupled to an activation assembly having a handle portion.
  • 26. The method of claim 25, where the actuation assembly further comprises a spool member coupled to the suture, and where applying tension to the suture comprises activating the spool member to apply tension to the suture.
  • 27. The method of claim 23, further comprising applying a tensile force between the rod portion and shaft such that an attachment location therebetween fractures permitting the rod to be detached from the shaft.
  • 28. The method of claim 27, where the attachment location comprises an internal threaded portion within the shaft and an external threaded portion on the rod, such that the tensile force comprises sufficient force to strip either the external threaded portion on the rod or the internal threaded portion on the shaft to detach the rod from the shaft.
  • 29. The method of claim 20, further including the step of trimming the suture after the step of actuating the anchor.
  • 30. The method of claim 19, where the anchor body is non-deformable and where inserting the anchor body into the cavity comprises partially deforming the wall of the body cavity.
  • 31. The method of claim 30, where the anchor body is generally tubular and has a plurality of tapered ridges circumferentially located about the anchor body and permit insertion of the anchor body into the body cavity when advanced in a first direction and resist removal of the anchor body when withdrawn in an opposite direction.
  • 32. The method of claim 31, where the body cavity is formed in bone and the plurality of ridges interfere with a cortical layer of the bone,
  • 33. The method of claim 19, where passing the free end of the suture comprises affixing the free end of the suture to a snare and withdrawing the snare through the anchor body lumen and through the portion of the locking plug.
  • 34. The method of claim 19, wherein the soft tissue is a cartilage and a body cavity is formed in a bone.
  • 35. The method of claim 34, wherein the cartilage is a glenoid labrum, and wherein the bone is the glenoid.
  • 36. The method of claim 19, wherein the portion of the suture secured in the soft tissue comprises a loop, and where the remaining free ends of the suture pass into the anchor.
  • 37. A method for knotless securing of soft tissue to hard tissue, the method comprising: providing an anchor having an anchor body and a locking plug, where the locking plug is moveable through a lumen of the anchor body until a stop of the locking plug contacts the anchor body;securing a suture to the soft tissue;advancing a first section of the suture through the stop and through the body lumen;tensioning a portion of the suture; andsecuring the anchor into a cavity formed in the hard tissue, such that the first section of the suture is compressed between the anchor body and the locking plug and a second section of the suture is compressed between a wall of the cavity and an exterior of the anchor body.
  • 38. The method of claim 37, where securing the anchor comprises moving the locking plug relative to the anchor body until a stop on the locking plug prevents further movement.
  • 39. The method of claim 38, where moving the locking plug relative to the anchor body occurs within the cavity.
  • 40. The method of claim 39, where the locking plug is withdrawn into the anchor body.
  • 41. The method of claim 39, where the anchor body is advanced over the locking plug.
  • 42. The method of claim 37, wherein the soft tissue is a cartilage, and the hard tissue is bone.
  • 43. The method of claim 42, wherein the cartilage is the glenoid labrum, and wherein the bone is the glenoid.
  • 44. The method of claim 37, wherein the portion of the suture secured in the soft tissue comprises a loop, and where the remaining free ends of the suture pass into the anchor.
  • 45. The method of claim 37, wherein said tensioning is performed semi-automatically.
  • 46. The method of claim 37, wherein said tension is performed by rotating a knob.