Abstract:
An apparatus and method for surgically reducing and internally fixing a shoulder acromioclavicular joint dislocation are disclosed. The apparatus preferably comprises a button and a washer, the washer being flexibly secured to the coracoid process of the scapula by means of a bone screw, the button and washer being secured together by means of a first suture. A second suture is provided secured between the button and a needle, such that the needle and associated button, may be advanced through a hole drilled through the clavicle, wherein the button and the washer may then be tightened, reducing the coracoclavicular distance, by means of the first suture connected therebetween, to reduce and hold a desired acromioclavicular joint dislocation.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application Ser. No. 60/697,125 filed on Jul. 7, 2005, the entire disclosure of which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to an apparatus and a method for internal fixation of an acromioclavicular joint dislocation of the shoulder with resultant superior migration of the lateral end of the clavicle with respect to the acromium and the coracoid of the scapula.  
       BACKGROUND OF THE INVENTION  
       [0003]     Acromioclavicular (“AC”) joint dislocations are characterized by severe upward displacement of the lateral end of the clavicle relative to the acromium of the scapula. Surgery is recommended to reduce and internally fix the displacement, which could otherwise lead to a painful deformity and loss of function.  
         [0004]     This invention relates to reconstruction surgery and particularly to reconstruction surgery for Rockwood types II-VI AC joint dislocations of the shoulder (Rockwood, Williams, &amp; Young,  Injuries to the Acromioclavicular Joints,  in FRACTURES IN ADULTS 1341-1413 (Rockwood &amp; Green, eds., 3 rd  ed., 1996)). More particularly, the invention relates to the use of a first suture anchor-suture-second suture anchor technique to reduce and internally fix the dislocation between the clavicle and the coracoid process.  
         [0005]     Injuries to the AC joint are generally classified as types I-VI, depending on the type and amount of disruption to the AC and the coracoclavicular ligaments. A type III AC dislocation of the shoulder is a common injury that occurs primarily from having a fall to the point of the shoulder. A type III injury is characterized by disruption of the AC and coracoclavicular ligaments, the dislocation of the AC joint and the upward relative displacement of the lateral end of the clavicle. The coracoclavicular interspace is greater than in the normal shoulder.  
         [0006]     There are presently two basic treatment options available: non-operative treatments and operative procedures.  
         [0007]     The non-operative option includes external, closed reduction. Various external, closed reduction procedures have been tried in the past using straps, casts, and different taping techniques. Generally, it has been believed that the procedures would work if applied continuously. Unfortunately, it has been found not to work as no one can wear them continuously because of skin breakdown and discomfort. As a result, such treatment regimes rarely have been successful. The patient must inevitably accept a cosmetic deformity and suffer from pain and fatigue after prolonged physical activity or heavy lifting.  
         [0008]     Operative treatments to date have focused on open reduction and direct repair or reconstruction of the ligaments. This procedure corrects the deformity and is generally accepted as providing the best results. However, this usually entails an extensive open operation. The deltoid and trapezius muscles are taken off the clavicle and dissected to expose the underside of the clavicle and the coracoclavicular ligaments and the coracoid process. The procedure requires an in-hospital stay, extended time for the surgical wound to heal, and rehabilitation. The open reduction procedure is generally recommended as the treatment of choice for people involved in heavy lifting work or active athletics. The remaining population is generally told to accept the deformity and to accept the pain and fatigue after heavy lifting or activity.  
         [0009]     It is well-known in the art to fix the coracoclavicular space by drilling a hole through the clavicle and into the coracoid process and by then inserting a screw (a Bosworth screw, for example) therebetween. It is also well-known to loop a flexible coupling such as a nylon tape around both the coracoid and the clavicle and to knot them together. This has the disadvantage of requiring that all of the coracoid be exposed. It is also known to drill a hole in the coracoid process and attach a single suture anchor, with a pair of sutures extending therefrom, into the coracoid. The free ends of the sutures are then looped about the clavicle and tied to each other.  
         [0010]     Non-operative treatment options generally provide unacceptable results. The open reduction treatment, while providing generally good results, has the disadvantage of an in-hospital stay plus the extensive time required for healing and rehabilitation. A surgical outpatient technique that would correct the deformity and allow healing of the injury in a normal anatomic position without extensive tissue dissection and less scarring would provide a substantial improvement over current treatment methods.  
         [0011]     It is an object of the present invention to overcome the problems associated with the prior art, whilst permitting normal physiological movement of the clavicle relative to the coracoid.  
       BRIEF SUMMARY OF THE INVENTION  
       [0012]     The present invention relates to a surprising use of a first suture anchor-suture-second suture anchor technique. The proposed method of the present invention is simple and is performed by a mini-open approach.  
         [0013]     In a first aspect of the present invention there is provided an apparatus for use in internal fixation of AC joint dislocations of a shoulder. The apparatus of the first aspect of the present invention is a kit of parts for internal fixation of an AC joint dislocation of a shoulder, the shoulder including a clavicle, a coracoid process and an acromium, the kit of parts comprising a first suture anchor; a second suture anchor, the first and second suture anchors being adapted for engagement in or on the clavicle and the coracoid process, respectively; a flexible coupling mountable, in use, between the first and second suture anchors; and a needle releasably securable to at least one of the first and second suture anchors, in which the first and second suture anchors each have at least first and second apertures and the flexible coupling is a first suture which is double looped through the first and second suture anchors.  
         [0014]     Preferably, the first suture is fed, in use, through a first aperture of the second suture anchor, and through, in turn, the second and first apertures of the first suture anchor and through, in turn, second and first apertures of the second suture anchor, and through, in turn, the second and first apertures of the first suture anchor and through the second aperture of the second suture anchor.  
         [0015]     Preferably, the first suture anchor comprises a button and the second suture anchor comprises a washer, the washer being adapted and dimensioned to engage with a bone anchor. Alternatively, each of the first and second suture anchors can be a button. In another embodiment, each of the first and second suture anchors can be a washer, the washer being adapted and dimensioned to engage with a bone anchor. In yet another embodiment, the first suture anchor is a washer and the second suture anchor is a button. The bone anchor may be a bone screw, a bone nail, a bone staple or an intraosseous bone anchor. A bone screw is preferred. Even more preferably, the washer has a central aperture and at least two, preferably at least four, peripheral apertures, the central aperture being adapted and dimensioned to accept a bone screw.  
         [0016]     More preferably, the first suture anchor is a button having an oblong body and first and second apertures and the second suture anchor is a washer adapted to engage with a bone anchor and having at least two, preferably at least four, peripheral apertures. In this embodiment, the first suture is fed through a first peripheral aperture of the washer and through, in turn, the second and first apertures of the button and through, in turn, second and third peripheral apertures of the washer, and through, in turn, the second and first apertures of the button and through the fourth peripheral aperture of the washer. A loop is formed on the underneath of the washer, by the path of the first suture between the second and third peripheral apertures. If desired, the free ends of the first suture may be fed under this loop, to provide a self-tightening suture.  
         [0017]     When one or both of the suture anchors is a button, the needle is preferably secured to one or both of the first and second buttons by means of a second suture looped through one of the first or second apertures of the first and/or second buttons, the second suture being operatively associated with the needle.  
         [0018]     In a second aspect of the present invention there is provided a method for internal fixation of AC joint dislocations. The method of the present invention comprises the steps of providing an apparatus according to the first aspect of the present invention; securing the first and second suture anchors on or adjacent the clavicle and the coracoid process, respectively; and reducing and fixing the distance between the clavicle and the coracoid process, by traction of the flexible coupling.  
         [0019]     When the apparatus of the first aspect of the invention comprises a button as the first suture anchor and a washer as the second suture anchor, the method preferably comprises the steps of drilling a clavicle hole through the clavicle and a coracoid hole into the coracoid process; passing the needle through the clavicle hole, so as to advance the button longitudinally through the clavicle hole; pivoting the button so as to engage the button against a superior surface of the clavicle; inserting a screw through a central aperture of the washer into the coracoid hole in a superior aspect of the coracoid process; and reducing and fixing the distance between the clavicle and the coracoid process, by traction of the flexible coupling. Preferably, the needle is uncoupled from the button when the button has been advanced through the clavicle hole and has engaged against the superior surface of the clavicle.  
         [0020]     It will be appreciated by those skilled in the art that traction of the flexible coupling can be effected by hand traction or by the use of a suture tensioner. Suitable suture tensioners are well known in the art.  
         [0021]     In a third aspect of the present invention there is provided a button for use in the apparatus of the first aspect of the invention and for use in the method of the second aspect of the present invention. The button of the third aspect of the invention can be used as either the first or second suture anchor or as each of the first and second suture anchors. The button of the third aspect of the present invention may comprise an oblong body defining first and second apertures. Preferably, each of the first and second apertures is oblong, their longitudinal mid-lines being located substantially about a longitudinal mid-line of the oblong body.  
         [0022]     Alternatively, each of the first and second apertures is substantially triangular in plan view. In this alternative embodiment, each aperture is tapered and terminates in an apex, the apices being directed away from each other. Preferably, each of the apertures comprises first, second and third walls and the first walls of the respective first and second apertures are substantially parallel.  
         [0023]     The button of the third aspect of the present invention may have any suitable dimension (width, length and thickness). If the button is oblong, for example, the button of the third aspect of the present invention can have a width of 2.5 mm to 4.0 mm without compromising implant strength, although a width of 3.0 mm to 4.0 mm is preferred. The length of the button of the third aspect of the present invention is less critical but may, for example, be in the range 7.5 mm to 12.5 mm. A length in the range 9 mm to 11 mm is preferred since the button of the third aspect of the present invention is then slightly less palpable under the skin following implantation.  
         [0024]     Each of the first and second apertures of the button of the third aspect of the present invention may have any shape or geometry. For example, one embodiment is an aperture which is substantially triangular in plan view. Another embodiment is an egg-shaped or oval aperture, the curved narrower end comprising the apex.  
         [0025]     In a fourth aspect of the present invention there is provided a washer for use in the apparatus of the first aspect of the invention and for use in the method of the second aspect of the present invention. The washer of the fourth aspect of the invention can be used as either the first or second suture anchor or as each of the first and second suture anchors. The washer of the fourth aspect of the present invention comprises a body adapted for engagement with a bone anchor and having at least two, preferably at least four, peripheral apertures. The washer of the fourth aspect of the present invention optionally comprises a disc-shaped body defining a central aperture shaped and dimensioned to accept a bone screw and having four peripheral apertures. Preferably, each of the central and peripheral apertures is circular in plan view.  
         [0026]     The washer of the fourth aspect of the present invention can have an external diameter of 6.5 mm to 13.0 mm and a thickness of 1.0 mm to 2.0 mm without compromising implant strength, although an external diameter of 8 mm to 12 mm and a thickness of about 1.5 mm is preferred. The central aperture of the washer of the fourth aspect of the present invention can have an internal diameter of 2.5 mm to 6.5 mm, although an internal diameter of 3.5 mm to 5.5 mm is preferred. In an optional embodiment, the four peripheral apertures of the washer of the fourth aspect of the present invention can have an internal diameter of 0.5 mm to 2.0 mm, although an internal diameter of 0.8 mm to 1.2 mm is preferred.  
         [0027]     As used herein, the term “button” or “washer” is intended to mean any suitably shaped and dimensioned suture anchor or stress bearing member which is capable of transmitting a force incident thereon to any body with which the button or washer is in contact. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0028]     These and other features and advantages of the invention will be more apparent from the following detailed description that is provided in connection with the accompanying drawings and illustrated exemplary embodiments of the invention, in which:  
         [0029]      FIGS. 1 and 1   a  show an anterior view and a schematic view, respectively, of a normal acromioclavicular joint;  
         [0030]      FIGS. 2 and 2   a  show an anterior view and a schematic view, respectively, of a Rockwood Type III acromioclavicular joint dislocation, with superior migration of the clavicle with respect to the acromium;  
         [0031]      FIG. 3  shows a plan view of a first or second suture anchor in the form of a button of the present invention;  
         [0032]      FIG. 4  shows perspective, plan and sectional view of an alternative embodiment of a button according to the invention;  
         [0033]      FIGS. 5 and 5   a  show a plan and an undersurface view, respectively, of a first or second suture anchor in the form of a washer of the present invention;  
         [0034]      FIG. 5   b  illustrates the mobile positioning of the washer against an arcuate undersurface of the screw-head of a bone anchor;  
         [0035]      FIG. 6  shows a perspective view of the kit of parts comprising an apparatus of the present invention; and  
         [0036]      FIGS. 7   a - 7   f  illustrate, in sequence, the steps of a method according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0037]     In the following detailed description, reference is made to the accompanying drawings, which form a part hereof and illustrate specific embodiments in which the invention may be practiced. In the drawings, like reference numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized, and that structural, logical and electrical changes may be made without departing from the spirit and scope of the present invention.  
         [0038]     The present invention provides minimally invasive, flexible fixation of the AC joint dislocation by resisting superior migration of the clavicle with respect to the coracoid process. It allows physiological micromotion at the AC joint. There should be no need for routine removal of the implant.  
         [0039]     The present invention is indicated for use in the fixation of AC joint dislocation. These are typically seen in Rockwood type III AC joint dislocations, usually caused by severe downward blunt trauma to the point of the shoulder, or acromium. Typically, the clavicle is upwardly displaced as a result of the injury because of disruption to the AC and coracoclavicular ligaments. Reduction and fixation of displaced AC joint dislocations are necessary to prevent painful deformity and loss of function.  
         [0040]      FIGS. 1 and 1   a  show anterior and schematic views of a normal shoulder  10 .  FIGS. 2 and 2   a  show anterior and schematic views of a shoulder  10  that has suffered a Rockwood type III AC joint dislocation injury.  
         [0041]     Referring to  FIGS. 1 and 2 , the structure of a shoulder  10  relevant to a Rockwood type III dislocation injury includes the clavicle  12 , the coracoid process  14  and the acromium  16 . The acromium  16  and the clavicle  12  are connected by the acromioclavicular ligament  18 . The acromioclavicular ligament  18  extends from the lateral end  20  of the clavicle  12  to the medial surface  22  of the acromium  16 . The coracoid process  14  is connected to the clavicle  12  by the coracoclavicular ligaments  24 , which comprise the trapezoid ligament  26  and the conoid ligament  28 . The coracoclavicular ligaments  24  extend from the inferior surface  30  of the clavicle  12  to the superior surface  32  of the coracoid process  14 .  
         [0042]     A Rockwood type III AC joint dislocation is characterized by the disruption of the AC and the coracoclavicular ligaments  18 ,  24 , respectively. As shown in  FIGS. 2 and 2   a , the clavicle  12  separates from, and moves away from, the coracoid process  14  and the acromium  16 , accompanied by disruption of the coracoclavicular and the AC ligaments  18 ,  24 , respectively. The acromioclavicular joint  34  ( FIG. 2 ) is dislocated and the clavicle  12  is relatively displaced upwardly. The coraco-acromial ligament  36  ( FIG. 1 ) is not impacted in the type III shoulder dislocation.  
         [0043]     Repair of the type III shoulder dislocation according to the present invention is an out-patient procedure performed with a general anesthetic. The procedure is done with the patient lying supine on the operating table, preferably in the “deck-chair” position to allow the surgeon full access to the affected shoulder.  
         [0044]     Referring to  FIG. 3 , the apparatus of the present invention comprises a first or second suture anchor in the form of a button  50 , which, in the embodiment illustrated, is about 10.0 mm in length by about 3.5 mm in width. The button  50  is preferably formed from titanium or stainless steel, although it will be appreciated that any other suitable material could be used, in particular any suitable bioabsorbable material. The button  50  has a first aperture  52  and a second aperture  54  which, in the embodiment illustrated, are oblong in shape, the longitudinal mid-line of each of the first and second apertures  52 ,  54  being located substantially about a longitudinal mid-line of the button  50 .  
         [0045]     Referring to  FIG. 4 , there is illustrated an alternative first or second suture anchor, generally indicated as  150 . In the illustrated alternative embodiment, the button  150  is about 9.0 mm in length by about 3.5 mm in width, with a thickness of about 1.5 mm. The button  150  has first and second apertures  152  and  154 , respectively. In the illustrated alternative embodiment, each of the apertures  152 ,  154  are triangular in shape, the respective apices  155  being directed away from each other and being located substantially about a longitudinal mid-line of the button  150 .  
         [0046]     Reference is now made to  FIGS. 5 and 5   a  which illustrate a first or second suture anchor in the form of a washer  60 . In the illustrated embodiment, the washer  60  has an external diameter of about 10.0 mm. While the illustrated washer is disc-shaped, the washer is not so limited. The washer  60  is preferably formed from titanium or stainless steel although, as will be appreciated by those skilled in the art, any other suitable material, in particular any suitable bioabsorbable materials, may be used. The washer  62  also has at least two flexible coupling-locating apertures  64 . In the illustrated embodiment, there are four apertures  64  circumferentially arranged about the aperture  62 . In the illustrated embodiment, each of the apertures  64  has a diameter of about 1.0 mm. Each of the apertures  64  have beveled edges, above and below, while the aperture  62  has beveled edges above.  
         [0047]     The washer  60  also has a substantially centrally located bone screw-retaining aperture  62 . In the illustrated embodiment, the aperture  62  has a diameter of about 4.6 mm and the washer  60  is adapted to allow mobile positioning against an arcuate undersurface  69  of the head of the bone screw  68  (illustrated in  FIG. 5   b ).  
         [0048]     Referring to  FIGS. 5 and 5   a , the washer  60  of the fourth aspect of the present invention is provided with a screw-retaining aperture  62  and at least two flexible coupling-locating apertures  64  which are preferably countersunk so as to allow easier threading passage of the flexible coupling  70  (not shown in  FIGS. 5-5   b ). Care needs to be taken in such countersinking, to avoid compromising the mechanical strength of the apertures  62 ,  64  of the washer  60 .  
         [0049]      FIG. 6  illustrates the implant apparatus used for fixation of the AC joint dislocation. The button  50  and the washer  60  are secured or pre-threaded together by means of a flexible coupling in the form of first suture  70 , preferably of number 5-strength braided polyester, which is double looped through the first and second apertures  52 ,  54  of the button  50  and the peripheral apertures  64  of the washer  60 , as will now be described in greater detail. Specifically, the first suture  70  is fed through to aperture  64   a  of the washer  60 ; through the second and first apertures  54 ,  52  of the button  50 ; through the aperture  64   b , under the washer  60  and back out the aperture  64   c ; through the second and first apertures  54 ,  52  of the button  50  again; and finally through the aperture  64   d  of the washer  60 . A needle  72 , which may be straight or curved, with a second, pull-through suture  74  is also looped through either the first or second apertures  52 ,  54  of the button  50 . The second suture  74  is looped through the first aperture  52  of the button  50 .  
         [0050]     The first suture  70  used in the apparatus can be made from any material which is suitable for this purpose, whether absorbable or non-absorbable, provided it is sufficiently strong. A number 5-strength braided polyester (FIBERWIRE®) suture is preferred. This is a non-absorbable suture which knots easily without slipping. The second suture  74  can be made from any material which is suitable for this purpose, and preferably should be at least 0-strength.  
         [0051]     The pull through needle  72  can be of any dimensions, provided it is long enough to span the clavicle  12  or the coracoid process  14  of the shoulder  10 . The needle  72  is preferably about 100 mm in length. The needle&#39;s body can either be straight or curved. The needle&#39;s tip can be either “taper cut” or “cutting.” 
         [0052]     In the present embodiment, leading and trailing edges of the button  50  are substantially symmetrical, although it will be appreciated that this is not a requirement of the present invention. Specifically, the leading edge  56  (illustrated in  FIG. 6 ) of the button  50  should be blunt and should have a width sufficient to reduce the possibility that the leading edge  56  of the button  50  follows the second or pull-through suture  74  through the intact skin or to catch or skewer any soft tissue structures between the bone and the skin, as will be described in detail hereinafter.  
         [0053]      FIG. 6  also illustrates a bone screw  68  as part of the implant apparatus. The bone screw  68  is used for engaging the washer  60  with the coracoid process  14  ( FIG. 7   f ). As discussed below in detail and with reference to  FIG. 5   b , the bone screw  68  has an arcuate undersurface  69  for defining the movement of the washer  60  between the coracoid process  14  and the arcuate undersurface  69 .  
                         TABLE 1                       Apparatus/Button of  FIGS. 3 and 6                                  Button 50 overall   10.0 mm (length) × 3.5 mm (width) × 1.5 mm       dimensions:   (thickness)       Basic shape:   Oblong in plan shape, with chamfered or           rounded corners and edges - this reduces           the chance of the button 50 being palpated           under the skin and, in addition, eases the           passage of the button 50 through a drill hole           as will be explained hereinafter.       Button 50 material:   Preferably titanium or stainless steel       Button apertures 52, 54:   Two apertures 52, 54 (oblong in plan shape)       Apertures 52, 54   2 mm height × 3 mm length (oblong with       dimensions:   chamfered edges), preferably 1 mm distance           between first and second apertures       Suture 70 (first suture):   Number 5-strength braided polyester suture,           looped twice through the first and second           apertures 52, 54 of the button 50 and each of           the four peripheral apertures 64 (64a, 64b,           64c, 64d) of the washer 60, leaving the two           free ends of suture 70 free for tying adjacent           the undersurface of the washer 60.       Pull-through needle 72:   100 mm long straight, or curved, needle 72           with pull-through, or second suture 74           attached.       Pull-through suture 74:   Minimum 0-strength suture 74 looped           through the aperture 52 of the button 50,           second suture 74 being secured to needle 72.                    
         [0054]     The following sets out the procedure, as shown in  FIGS. 7   a - 7   f , to be followed for Rockwood Type III dislocations. Surgeons skilled in the art will appreciate the modifications that might be needed in addressing Rockwood Type II and IV-VI dislocations.  
         [0000]     Set-up  
         [0055]     The patient is positioned in a “deck-chair” position on the operating table (not shown). A sandbag (not shown) can be placed under the scapula to ease access to the shoulder region. A longitudinal or horizontal incision of about 5 cm is made on the skin, at the front of the shoulder, overlying the coracoid process  14  and the clavicle  12 . The clavicle  12  and the superior surface of the coracoid process  14  are exposed by blunt dissection. As explained in detail below, if the clavicle hole  80  is to be drilled ( FIG. 7   a ) from above and substantially downwardly through the clavicle  12 , it will also be necessary to retract the skin about the clavicle  12 , in order to expose the superior surface  33  of the clavicle  12 .  
         [0000]     Instrumentation  
         [0056]     A 3.5 mm drill bit is required for drilling a hole  80  through the clavicle  12 . A 2.5 mm drill bit is required for drilling a hole  82  into the base of the coracoid process  14  of the scapula ( FIG. 7   a ). It is not necessary that the drill holes  80 ,  82  be aligned with each other. In addition, it is not necessary, when the coracoclavicular interspace is reduced to normal, that the longitudinal axes of the respective drill holes  80 ,  82  be co-linear or even substantially parallel with each other.  
         [0000]     Button Placement  
         [0057]     As illustrated in  FIG. 7   b , the long straight needle  72  with pull-through, second suture  74  is passed upwards through the 3.5 mm drill hole  80  in the clavicle  12  and can be passed through the intact skin on the superior aspect of the clavicle  12  or through the open surgical wound. In  FIG. 7   c , the pull-through suture  74 , which engages the first aperture  52  (not shown) of the button  50 , can now advance the button  50 , substantially longitudinally through the drill hole  80 . Engagement of the second suture  74  in the aperture  52  (not shown) ensures that the second suture  74  is located adjacent the longitudinal mid-line of the button  50  so that the second suture  74  stays central in the first aperture  52 .  
         [0058]     In  FIG. 7   d , once the button  50  has exited the superior surface  33  of the clavicle  12 , the angle of traction on the pull-through, or second, suture  74  is changed and counter-traction is exerted on the first suture  70 , in order to flip (pivot) the button  50  and engage the button  50  against the superior surface  33  of the clavicle  12 . Once the button  50  is anchored, the pull-through, or second, suture  74  can be cut and removed ( FIGS. 7   d  and  7   e ). In  FIG. 7   f , the screw  68  containing the washer  60  is inserted into the 2.5 mm drill hole  82  ( FIG. 7   e ) in the base of the coracoid process  14  of the scapula. Before the washer  60 /bone screw  68  is fully seated into the drill hole  82 , the acromioclavicular joint  34  is reduced by downward manual pressure on the lateral end  20  of the clavicle  12  ( FIGS. 7   e  and  7   f ).  
         [0059]     The two trailing ends of the first suture  70  ( FIG. 7   e ) are pulled to approximate the desired distance between the button  50  and the washer  60 , and hence reduce the interval between the clavicle  12  and the coracoid process  14 . The first suture  70  is then secured to itself with a knot, tied tight by hand. The free ends of the first suture  70  can then be cut approximately 1 cm long, to avoid knot slippage. The screw  68  can then be fully seated into the drill hole  82  in the coracoid process  14  to maximize suture tension, or may be advanced or retracted accordingly to fine tune the suture tension, according to the surgeon&#39;s preference.  
         [0060]     The volume between the arcuate undersurface  69  of the bone screw  68  and the coracoid process  14  defines the maximum flexibility of the washer  60  therebetween. The designed flexibility is helpful in increasing the tolerance for non-aligned drill holes and the like.  
         [0000]     Post-Operative Management  
         [0061]     Following wound closure, the shoulder should be placed in a shoulder immobilizer for three weeks. Gentle range of motion exercises can begin after three weeks. Full range exercises can be allowed after six weeks.  
         [0000]     Implant Removal  
         [0062]     Routine removal of the first suture anchor-suture-second suture anchor construct is not required. If, for any reason, it needs to be removed, this can be performed simply by re-opening the surgical incision, cutting the first suture  70  as it loops through the button  50  and removing the button  50 . The screw  68  and washer  60  can be removed easily using the screwdriver.  
         [0063]     It is noted that the above description and drawings are exemplary and illustrate preferred embodiments that achieve the objects, features and advantages of the present invention. It is not intended that the present invention be limited to the illustrated embodiments. Any modification of the present invention which comes within the spirit and scope of the following claims should be considered part of the present invention.