Patent Publication Number: US-2012041496-A1

Title: Swivel Screw Ligament Fixation Device

Description:
FIELD OF THE INVENTION 
     The present invention relates to fastening devices and in particular to screw fastening devices. 
     The invention has been developed primarily for use as a fastener that can be used from within a bone tunnel to pull a graft (including tendons or ligament) though a tunnel (or hole) in a bone and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use. 
     BACKGROUND OF THE INVENTION 
     Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field. 
     The present disclosure will be used with reference to an anterior cruciate ligament (“ACL”) reconstruction, but it will be understood that the technology and methods of the present invention may have other applications. 
     The ACL reconstruction can be done in numerous ways. All common methods involved drilling holes or tunnels in the femur and tibia. These can be drilled from any direction using a variety of techniques. Grafts such as autografts, allografts or artificial biomaterials may be used to extend between the femoral tunnel and the tibial tunnel. The graft is then fixed to the appropriate bone structure, again numerous techniques being suitable. The replacement graft is fixed to the femur and tibia, most commonly by a screw into the adjacent bone, it being understood that staples, pins and similar devices may also be used. In general, and most commonly, the graft is tensioned prior to finally affixing it to the bone. Devices are known that can exert tension onto the graft before affixation to the bone takes place. These tension devices hold the graft in tension while fixing screws are inserted to fasten the graft in place. Therefore, this tension device can not fine tune or adjust the tension of the graft once the remaining lose end is fixed in place. 
     Object of the Invention 
     It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. 
     It is an object of the invention in its preferred form to provide a device for tensioning a graft in an ACL reconstruction. 
     It is an object of the invention in its preferred form to provide a device and methods for adjusting graft tension, after both ends are affixed to the bone. 
     SUMMARY OF THE INVENTION 
     According to an aspect of the invention there is provided a surgical screw fastener device for pulling a graft through a first tunnel defined in a first bone, the surgical screw fastener including:
         a body having a proximal end and a distal end;   an exterior screw thread located around the body for threadedly engaging a wall of the first tunnel;   a first coupling element at the proximal end of the body, the first coupling element adapted to couple a driver tool; and   a second coupling element for rotatable coupling a first end of the graft with respect to the device.       

     Preferably, the passage is a through passage having an aperture at the distal end and the proximal end. 
     Preferably, the first coupling element is a female socket at the proximal end of the body. More preferably, the passage is a through passage having an aperture at the proximal end that defines the socket. 
     Preferably, the first coupling element is a releasable coupling element for securely coupling the device to the driver tool. 
     Preferably, the passage has an aperture at the distal end; and the a second coupling element comprises a saddle element that is locatable within the passage and is adapted to be rotatable with the passage. More preferably, the saddle element is locatable within the passage by being passed through an aperture at the proximal end defined by the passage. Most preferably, the saddle element is adapted to rotate freely within the passageway and is restrained in its axial movement toward the distal end by a necking down of the passageway. 
     Preferably, the second coupling element comprises a saddle element locatable within the passage, and is adapted to be rotatable with the passage; and the a second coupling element further comprises a fastening element coupled to the saddle element and adapted to retain a first end of the graft. Preferably, the fastening element is integrally formed with the saddle element. Preferably, the fastening element is integrally formed with an artificial graft. Preferably, the fastening element is constructed of a flexible material. 
     Preferably, the fastening element includes any one or more of the set comprising: a loop element; a net element. 
     Preferably, selective clockwise or anticlockwise rotation of the body, while threadedly engaging the wall of the first tunnel, can respectively increase or decrease tension applied to the graft. Alternatively, selective anticlockwise or clockwise rotation of the body, while threadedly engaging the wall of the first tunnel, preferably respectively increase or decrease tension applied to the graft. 
     According to an aspect of the invention there is provided a method of using a surgical screw fastener device for pulling a graft through a first tunnel defined in a first bone, the method comprising the steps of:
         (a) providing a screw fastener device;   (b) coupling the screw fastener to a driver tool passed through the first tunnel;   (c) rotatably coupling a first end of the graft to the device;   (d) rotating the screw fastener, by rotating the driver tool, causing the screw fastener to threadedly engage the bone and thereby draw the graft up though the tunnel;   (e) with other end of the graft fixed in location, the screw fastener can be rotated with respect to the bone to thereby set a tension applied to the graft; and   (f) detaching the screw fastener from the driver tool.       

     Preferably, the screw fastener device is as herein described. 
     Preferably, fixing the other end of the graft includes abutment of an end plug fixed to the other end of the graft as a result of the device drawing up the graft. 
     According to an aspect of the invention there is provided a screw fastener having a longitudinal through passageway. One end of the passageway comprises a socket for receiving a fastener driver tool (or adaptor). The other end of the passageway provides a portal for the looped material or artificial graft. 
     A saddle is preferably located within the passageway. The saddle is not able to pass through the loop portal. The saddle is adapted to receive a suture, suture loop or a loop of material through which the graft is placed. More preferably, the saddle is able to rotate within the passageway when the suture and/or loop is in tension. 
     A saddle is preferably located within the passage but not able to pass through the loop portal. More preferably the saddle can rotate within the passage. Most preferably, with the screw fastener located within a tunnel (or hole) formed in a bone, the saddle enables the screw fastener to be rotated with respect to the bone without the tendon undergoing a corresponding rotation. 
     Preferably a screw fastener can be located within a tunnel (or hole) formed in a bone and rotatably coupled to a graft, wherein rotation of the screw fastener with respect to the bone pulls the graft though the tunnel. More preferably, rotation of screw fastener enables controlled pulling of a graft up though a tunnel. Most preferably, with each end of the graft coupled to a respective bone, rotation of screw fastener in one or another direction enables a respective increased and decreased tensioning of the graft. 
     In preferred embodiments the fastener has a pair of transverse openings, each leading to a longitudinal, external channel. The transverse openings in the channels are preferably adapted to receive a fastener such that the driver can be rotated in either direction. A lip on the inside of the screw prevents it from being pulled out of the screw. An alternative technique to couple the driver to the screw would be to have holes and a form of attaching suture to the screw for tying it to the driver either in a slot on the side of the driver or through the middle of the driver if cannulated. 
     A screw fastener preferably includes a locking mechanism that can pull the screw, in tension, thus into place and then be unlocked once the screw has the correct tension. 
     Preferably the driver is adapted to provide an indication of the torque on the fastener. 
     Preferably, screw fastener can be pulled into position by a driver. More preferably, the driver can be released once it screw fastener is in position. 
     Preferably a graft includes any one or more of the set comprising a transplant tendon, an artificial tendon and a transplant ligament, and an artificial ligaments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       In order that the invention be better understood, reference is now made to the following drawing figures in which: 
         FIG. 1A  is an underside perspective view of an embodiment fastener made in accordance with the teachings of the present invention; 
         FIG. 1B  is a top perspective view of the fastener depicted in  FIG. 1A ; 
         FIG. 2  is a side elevation of the fastener depicted in  FIG. 1A ; 
         FIG. 3  is a cross section through line  3 - 3  of  FIG. 2 ; 
         FIG. 4  is a perspective view of a saddle; 
         FIG. 5  is a side elevation view of an embodiment fastener with the saddle retaining a suture loop that passes through the portal; 
         FIG. 6  is a cross sectional view through line  6 - 6  of  FIG. 5 ; 
         FIG. 7A-7K  are perspective views illustrating steps involved in utilisation of the invention in conjunction with an ACL reconstruction; 
         FIG. 8A  is a perspective view of another embodiment form of driver and driver engagement; 
         FIG. 8B  is an enlarged perspective view of  FIG. 8A , showing detail of the driver engagement; 
         FIG. 8C  is a cross sectional view of an embodiment driver and engagement of  FIG. 8A ; 
         FIG. 8D  is a side elevation of the device depicted in  FIG. 8A ; 
         FIG. 9A  is a perspective view of a further embodiment of a driver; 
         FIG. 9B  is a cross section and detail of the driver depicted in  FIG. 9A , illustrating the engagement; 
         FIG. 9C  is an enlarged cross section of  FIG. 9B , showing detail of the driver engagement; 
         FIG. 10A  is a perspective view of an embodiment screw fastener made in accordance with the teachings of the present invention; 
         FIG. 10B  is a sectional view of the screw fastener of  FIG. 10A ; 
         FIG. 11A  is a perspective view of an embodiment screw fastener made in accordance with the teachings of the present invention; 
         FIG. 11B  is a sectional view of the screw fastener of  FIG. 11A ; 
         FIG. 12A  is a side elevation view of an embodiment driver; 
         FIG. 12B  is an enlarged partial side elevation view of the screw fastener engagement of the driver of  FIG. 12A ; 
         FIG. 12C  is an enlarged end elevation view of the driver of  FIG. 12A ; 
         FIG. 13A  is a side elevation view of an embodiment driver; 
         FIG. 13B  is an enlarged sectional end elevation view of the screw fastener engagement of the driver of  FIG. 13A , shown engaged with a screw fastener; 
         FIG. 14A  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention; 
         FIG. 14B  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention; 
         FIG. 14C  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention; 
         FIG. 14D  is a perspective view of an embodiment fastener made in accordance with the teachings of the present invention; 
         FIG. 15A-15D  are perspective views illustrating steps involved in utilisation of the invention in conjunction with an ACL reconstruction; and 
         FIG. 16  is a flowchart for an embodiment method of a screw fastener in conjunction with an ACL reconstruction. 
     
    
    
     BEST MODE AND OTHER EMBODIMENTS 
     As shown in  FIG. 1A , a fastener  100 , in accordance with the teachings of the present invention, comprises a relatively coarse threaded slightly tapered plug (or body)  110  having the fastening characteristics of a bone screw. External screw threads  120  are adapted to be self tapping into a tunnel pre-drilled through the tibia or femur. A central longitudinal bore or passageway  130  extends through the fastener, from one end to the other. 
     By way of example, a device of this kind will typically be about 6 mm to 14 mm in diameter and have a length of about 15 mm to 20 mm. 
     In an embodiment, a proximal end of the passageway  132  forms a socket for receiving a driver (including a adaptor and/or tool) such as a Torx brand driver. It will be appreciated that the socket, and therefore the head of a corresponding driver, can comprise numerous configurations, including a hex socket, and/or a star socket. A driver is adapted to accommodate the socket configuration. 
     Opposing longitudinal channels  140  extend approximately a third to halfway down the body of the fastener, into the screw threads, providing a relief groove that starts by intersection of the proximal rim  142  of the fastener and terminates at one of a pair of transverse through openings (not shown in this view). The channel  140  interrupts the screw threads and the proximal rim providing a space that can accommodate a loop of material such as polyethylene or polyester or other type of suture material without interfering with the operation of the fastener, the fastener&#39;s threads or the socket  130 . In this embodiment channels  140  are provided to enable the screw to facilitate more aggressive cutting engagement with the bone. 
     As shown in  FIG. 1B , the distal end  150  of the fastener  100  comprises a portal  152  that leads into the central bore or through passageway  130 . The portal  152  comprises a smoothly radiused rim and a smooth opening  154  for receiving the flexible loop or suture arrangement that will be described with reference to  FIG. 5  and  FIG. 6 . 
     As shown in  FIG. 2  and  FIG. 3 , each longitudinal, external channel  140  terminates in a transverse through opening. The through openings lead into the central passageway  310 . The longitudinal channel and transverse channels can be used for engaging and/or locking a cooperating pulling device or driver. 
     A saddle  320  is adapted to rotate freely within the passageway and is restrained in its axial movement toward the portal  152  by a necking down  312  of the passageway adjacent to the portal  152 . Saddle is not able to pass through the loop portal due to a lip on the inside of the screw fastener. The saddle rotates within the screw as a graft is being pulled up so as to not twist the graft (or tendon or ligament). 
     It will be appreciated that, references to a graft includes a transplant or artificial tendons and/or ligaments. 
     As shown in  FIG. 3 , the central passageway  310  is adapted to receive a saddle  320  between the openings  210  and the necking  312 . In preferred embodiments, the saddle is symmetrical about its transverse axis  322  so that it may be inserted into the passageway and used in either orientation. The edges of the longitudinal ends  324 ,  326  are radiused to cooperate with the necking  312 , thus reducing friction. Note that the through openings  210  are formed beyond the axial reach of the socket  130  so that the suture that passes through the openings  210  does not interfere with the head of the driver. 
     As shown in  FIG. 4 , the saddle  320  is generally “H” shaped, but can be of other shapes. The lateral components  410 ,  412  are essentially sections of cylinder and are joined together by a smooth integral cross member  420 . The cross member  420  is smoothly blended into the interior surfaces of the lateral portions  410 ,  412 . The cross member  420  is necked, providing a minimum diameter in the middle and a gradual flaring toward the lateral members  410 ,  412 . 
     As shown in  FIG. 5  and  FIG. 6 , a loop of fibre material (for example suture material)  510  may be passed around the cross member  420  of the saddle  320  to form a constrained loop. The loop  510  enters through and exits through the loop portal  152 . Note the lack of sharp edges in the area of the portal. 
       FIG. 7A-FIG .  7 K illustrate how the fastener is used in an embodiment method of an ACL reconstruction method. As shown in  FIG. 7A , through holes or tunnels  710 ,  712  are formed through the bones of the tibia  714  and the femur  716 . As shown in  FIG. 7B  a first suture material  720  forms a loop around the saddle as illustrated in  FIG. 6 . Typically, the first suture material comprises a loop extending around the saddle and adapted to extend below the screw fastener for receiving the graft. A second suture  725  passes through the transverse openings  210 . The second suture  725  is collected with a small hook  727  that is inserted through the tibial tunnel  710 . The second suture is then withdrawn from the opposite end of the tibial tunnel. In one embodiment, the free end of the second suture  725  is passed e.g. through the head, shaft and handle of an appropriate driver  730 , and tightened to the driver. This allows the driver  730  to be advanced through the tibial tunnel  710 . As shown in  FIG. 7F , the replacement tendon  740  is passed through the loop, whipped or otherwise attached to the first suture material  720 . It will be appreciated that the tendon can be placed through the loop before it is inserted into the knee or could be coupled when the tendon is in the knee By way of example, first suture comprises a loop extending around the saddle and adapted to forming a loop below the screw fastener for receive the tendon therethough. The driver  730  is fully inserted into the socket  130 . In this position, the second suture  725  is used to attach or temporarily lock the fastener onto the head of the driver  730  by tensioning the free end of the second suture  725 . As shown in  FIG. 7H  a third suture  750  is whip stitched onto the femoral side  742  of the replacement tendon structure  740  and the third suture  750  is picked up with a hook  727  and drawn through the femoral tunnel  712 . As shown in  FIG. 7I , the femoral end whip stitched suture is then pulled through the femoral tunnel and then affixed with an appropriate device to the femur bone. As suggested by  FIG. 7J , the femoral end of the tendon is now fixed to the femur and the tibial end of the tendon is affixed to the saddle within the threaded fastener  100 . At this point the driver  730  is rotated anti-clockwise  760 , thus retracting the fastener  100  into the tunnel  710  toward the driver  730 . It will be appreciated that in an alternative embodiment the screw thread can be configured such that clockwise rotation of the driver causes the screw fastener to be retracted into the tunnel. The retraction of the fastener  100  tensions the tendon and the degree of tension is determined by the extent of rotation and/or torque imposed by the surgeon. Because the saddle  320  rotates freely within the fastener  100 , the tendon does not become twisted as it becomes tensioned. When the appropriate tension is reached, the driver  730  and the second suture  725  can be withdrawn from the tibial tunnel  710 . This procedure can be done in either direction such that the screw can end up in the femur or tibia. 
     In an embodiment, a suture is used to fasten a driver to a screw fastener. The suture can be attached to the screw, typically passing through 2 holes in the screw fastener. By way of example, the suture can then be located to the side of the driver, or pass through the middle of a cannulated driver. The suture can be tensioned and tied at the proximal end of the driver to hold the screw in place so it can be pulled/drawn up to a tunnel in a bone. The suture is typically removed once the screw is in placed. 
     As shown in  FIG. 8A  and  FIG. 8B  a fastener  800  has been configured to receive a specially adapted driver  850 . The driver  850  comprises a generally cylindrical tip  852  having one or more radially extending pins or projections  854 . In this example, the driver  850  is provided with four pins. The pins are provided in adjacent pairs that are diametrically opposed to one another on the tip  852 . It will be appreciated that other configurations are contemplated. In particular, in an embodiment only one pin or protrusion by be provided. It will be appreciated that pins can be of any cross section, for example circular, square or rectangular. 
     In order that the fastener  800  receive the tip of the driver  852 , the internal bore  810  of the fastener  800  is provided with a pair of opposing internal longitudinal grooves  812 . The area radially outward of the terminus of a groove is machined away  816 . Clockwise rotation of the driver causes the pins  854  to abut an adjacent portion of the fastener  800  and thus cause the fastener to rotate and advance in the forward direction  820 . However, counter clockwise rotation of the driver  860  causes the pins  854  to rotate and thus depart from the groove or grooves  812  and come to rest in a position where withdrawal of the driver tip  852  is resisted by a portion of the fastener body. In this orientation, anti-clockwise rotation of the driver  860  acts to withdraw the fastener  800  (retrograde motion, i.e. in the direction opposition of arrow  820 ). Further, putting the driver into tension to assist in the withdrawal cannot disengage the driver from the fastener  800 . A small clockwise rotation of the driver realigns the pins  854  with the channels  812  so that the tip  852  can be withdrawn from the fastener  800 . 
     As shown in  FIG. 8C , the driver tip  852  can be constructed by providing transverse passageways for receiving the pins  854 . In this example, two pins extend through the entire diameter of the driver and beyond the outer surface to create four projections  854 . Note that the configuration of the internal grooves  812  prevents the extreme distal tip  856  of the driver from making contact with the saddle  320 .  FIG. 8C  also illustrates that by way of example only, and according to the present embodiment the radial extent of the pins  854  is below the root  832  of the cutting threads  830 . By making the tip diameter of the pins  854  smaller than even the smallest diameter root  834 , the insertion of the driver and its pins  854  is never resisted by bone material that may occupy the space between the threads  830 . 
     As shown in  FIG. 8D  each pin  854  comes to rest, after the driver has been inserted and rotated counter clockwise into a transverse side channel  840 . In the side channel (withdrawal position) it is preferred that the round pins  854  make surface contact  842  with the body of the fastener  800 . This requires that the side walls  842  of the groove&#39;s side-channel have a generally semi circular configuration where they are contacted by a round pin. It will be appreciated that, in an alternative embodiments, other co-operating configurations can be used, for example substantially rectangular pin and a square set groove. 
     Another example of a driver is depicted in  FIG. 9A  and  FIG. 9B . A retrograde fastener  900  has been configured to receive a specially adapted driver  950 . In this example, the tip  952  of the driver is in the form of a fastener extractor. The tip has hardened, tapered, coarse threads  954  that are anti-clockwise. As shown in  FIG. 9B  and  FIG. 9C , the extreme tip  956  of the driver can be inserted into the smooth interior bore  910  of the fastener  900 . Anti-clockwise rotation causes the threads  954  to advance and cut into the bore  910 . The fastener  900  is thus withdrawn through the bone tunnel with the anti-clockwise motion of the driver. The driver can be put into considerable tension without the threads  954  disengaging. Clockwise rotation of the driver causes the tip  956  to reverse of the bore  910  and thus causes disengagement of the driver with the fastener  900 . It will be appreciated that for this type of driver, the threads  954  must be harder than the internal bore  910  of the fastener  900 . 
       FIG. 10A  and  FIG. 10B  show an embodiment screw fastener  1000 . A first coupling element is shown at the proximal end of the body for coupling a driver tool. 
     This embodiment (similar to the embodiment screw fastener  100 ) comprises a relatively coarse threaded slightly tapered plug (or body)  1010  having the fastening characteristics of a bone screw. External screw threads  1020  are adapted to be self tapping into a tunnel pre-drilled through the tibia or femur. A central longitudinal bore or passageway  1030  extends through the fastener, from one end to the other. The proximal end  1032  of the passageway forms a socket for receiving a cooperating driver. It will be appreciated that the socket, and therefore the head of a corresponding driver, can comprise numerous configurations, including a inwardly scalloped hex socket. A receiving driver is adapted to accommodate the socket configuration. One or more transverse through openings  1042  can accommodate a loop of material such as polyethylene or polyester or other type of suture material without interfering with the operation of the fastener, the fastener&#39;s threads or the socket  1030 . 
     As shown in  FIG. 10B , the distal end  1050  of the fastener  1000  comprises a portal  1052  that leads into the central bore or through passageway  1030 . The portal  1052  comprises a smoothly radiused rim and a smooth opening  1054  for receiving the loop or suture arrangement as herein described. A saddle (not shown) is adapted to rotate freely within the passageway and is restrained in its axial movement toward the portal  1052  by a necking down  1062  of the passageway adjacent to the portal  1052 . 
       FIG. 11A  and  FIG. 11B  show an embodiment screw fastener  1100 . A first coupling element is shown at the proximal end of the body for coupling a driver tool. 
     This embodiment (similar to the embodiment screw fastener  100 ) comprises a relatively coarse threaded slightly tapered plug (or body)  1110  having the fastening characteristics of a bone screw. External screw threads  1120  are adapted to be self tapping into a tunnel pre-drilled through the tibia or femur. A central longitudinal bore or passageway  1130  extends through the fastener, from one end to the other. The proximal end  1132  of the passageway forms a socket for receiving a cooperating driver. 
     As shown in  FIG. 11B , the distal end  1150  of the fastener  1100  comprises a portal  1052  that leads into the central bore or through passageway  1130 . The portal  1052  comprises a smoothly radiused rim and a smooth opening  1154  for receiving the loop or suture arrangement as herein described. A saddle (not shown) is adapted to rotate freely within the passageway and is restrained in its axial movement toward the portal  1152  by a necking down  1162  of the passageway adjacent to the portal  1152 . 
     It will be appreciated that the socket, and therefore the head of a corresponding driver, can comprise numerous configurations, including a bayonet style connection. A receiving driver (as best shown in  FIG. 12  and  FIG. 13 ) is adapted to accommodate the socket configuration. 
     In this embodiment, a bayonet style connection  1170  can comprise a one or more longitudinal channels  1172  extending approximately a third to halfway down the periphery of longitudinal bore or passageway  1130 , providing a relief groove that starts by intersection of the proximal rim  1174  of the fastener and terminates at a radially scribed passageway  1176 . 
     By way of example only, when inserting a driver (not shown) into the socket  1130 , the bayonet style connection  1170  enables a releasable coupling such that the screw fastener  1100  can be pulled though or to a tunnel in a bone. A pin on the driver engages and traverses the longitudinal channel  1172 , such that upon full insertion of the driver, the driver can be axially rotated such that the pin sweeps the radially scribed passageway  1176 . 
     The configuration of the internal channel (or grooves) are adapted to prevent the extreme distal tip of the driver from making contact with the saddle. 
       FIG. 12A  and  FIG. 12B  show an embodiment driver (or adaptor)  1200  for using screw fastener (for example screw fastener  1100 ). 
     This embodiment driver (or adaptor)  1200  has an elongate shaft  1210 , terminating at one end with a coupling element for engaging a socket of a screw fastener. 
     The driver  1200  comprises a generally cylindrical tip (distal tip)  1212  having one or more radially extending pins or projections  1220 . In this example, the driver  1200  is provided with two oppositely directed radially extending pins on the tip  1212 . It will be appreciated that other configurations are contemplated. In particular, in an embodiment only one pin or protrusion be provided. 
     In order that the fastener (for example screw fastener  1100 , not shown) receive the tip of the driver  1212 , the internal bore of the fastener is provided with a pair of opposing internal longitudinal channels or grooves. The area radially outward of the terminus of a groove is machined away. Clockwise rotation of the driver causes the pins  1220  to abut an adjacent portion of the fastener and thus cause the fastener to rotate and advance in the forward direction. Counter clockwise rotation of the driver  1200  causes the pins  1220  to rotate and thus depart from the longitudinal channel or groove and come to rest in a position where withdrawal of the driver tip is resisted by a portion of the fastener body. In this orientation, further anti-clockwise rotation of the driver  1200  acts to draw the fastener (retrograde motion) though a tunnel in a bone. Further, putting the driver into tension to assist in the drawing (or withdrawal) of the fastener through a tunnel cannot disengage the driver from the fastener. A small clockwise rotation of the driver realigns the pins  1220  with the channels so that the tip  1212  can be withdrawn from the fastener. 
     As shown in each pin comes to rest, after the driver has been inserted and rotated counter clockwise into a transverse side channel. In the side channel (withdrawal position) it is preferred that the round pins make surface contact with the body of the fastener. This requires that the side walls of the groove&#39;s side-channel have a generally semi circular configuration where they are contacted by a round pin. It will be appreciated that, in alternative embodiments, other co-operating configurations can be used, for example substantially rectangular pin and a square set groove. 
     In this example the driver  1200  comprises a generally triangular proximal tip  1214  for receiving a handle, a torque driver, or a second driver (for example a drill). It will be appreciated that, in alternative embodiments, other co-operating configurations can be used. 
       FIG. 13A  and  FIG. 13B  show an alternative embodiment driver (or adaptor)  1200  for using screw fastener  1100 . 
     Similar to the embodiment shown in  FIG. 12A  and  FIG. 12B , this embodiment driver (or adaptor)  1300  has an elongate shaft  1310 , terminating at one end with a coupling element for engaging a socket of a screw fastener (as best shown in  FIG. 13B ). 
     The driver  1300  comprises a generally cylindrical tip (distal tip)  1312  having one or more radially extending pins or projections  1320 . Initial fastening of the driver to a screw fastener was outlined in the description referring to  FIG. 12A  and  FIG. 12B . 
     Referring to  FIG. 13B , in this embodiment, the internal bore of the fastener  1350  receives the tip of the driver  1312 , whereby the pins  1320  are received by a pair of opposing internal longitudinal channels or grooves  1352 . Counter clockwise rotation of the driver  1300  causes the pins  1320  to rotate and thus depart from the longitudinal channel or groove  1352  and sweep a respective radially scribed passageway  1354 . The pins come to rest in a position where withdrawal of the driver tip is resisted by a portion of the fastener body. 
     In this example the driver  1200  further comprises a longitudinally extending channel  1330 , such that when the driver is engaged with the screw fastener, the longitudinally extending channel  1330  of the driver aligns with an internal longitudinal channel  1352  of the screw fastener. An elongate rod or wire  1335  can be located within both channels  1330  and  1352  to restrict further relative rotation between the screw fastener and the driver. It will be appreciated that this configuration restricts the fastener from being able to fall off the driver. It will be further appreciated that, in an alternative embodiments, other locking configurations for restricting further relative rotation between the screw fastener and the driver can be used. Once the screw fastener is in place the thin wire can be removed to allow the driver to be decoupled from the screw fastener. 
       FIG. 14A  through  FIG. 14D  show alternative structures fastening element for rotatably coupling (or attaching) a graft/tendons to a screw fastener. However, it will be appreciated that structures for rotatably coupling (or attaching) a graft are not limited to these particular embodiments. These embodiments shows alternative second coupling element for rotatable coupling of a first end of the graft with respect to the device. 
     The screw fastener includes a body  1410  having an external screw thread  1420 . A central longitudinal bore or passageway  1430  extends through the fastener, from one end to the other. The proximal end  1440  of the passageway forms a socket for receiving a cooperating driver. The distal end  1445  of the screw fastener comprises a portal  1447  that leads into the central passageway  1430 . A saddle  1450  is adapted to rotate freely within the passageway and is restrained in its axial movement toward the portal  1447  by a necking down  1449  of the passageway adjacent to the portal. The graft  1470  is rotatably couplable to the screw fastener. 
     It will be appreciated that a first end  1472  of replacement tendons or graft  1470  will be rotatably couplable to a screw fastener, and the second (other) end fixedly couplable to a bone. Then replacement tendons are provided by tendons that are looped around a coupling operatively associated with the screw fastener, the first end is defined by the portion of tendons/graft adjacent the screw fastener (when rotatably coupled) and the second end is defined by free ends of tendons/graft (or the other end). 
       FIG. 14A  is a sectional view of an embodiment fastener  1400  made in accordance with the teachings of the present invention. 
     In this embodiment, a flexible loop element  1460  is located around the saddle  1450 . The loop extends below the portal  1447 , such that the graft (or tendons) can pass though and/or be coupled to the loop. The free ends of graft (or tendons) define the second end of the graft. A saddle  1450  is adapted to rotate freely within the passageway thereby providing a rotatable coupling between the screw fastener and the graft  1470 . The saddle  1450  and loop element  1460  can be located in the passageway  1430  by passing them though the opening at the proximal end  1440 . 
       FIG. 14B  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention. 
     In this embodiment, a flexible loop  1460  is integrally formed with the saddle  1450 , for example in the form of an expansion of the looped material. The loop extends below the portal  1047 , such that the graft (or tendons)can pass though and/or be coupled to the loop. The free ends of tendons define the second end of the graft. A saddle  1450  is adapted to rotate freely within the passageway thereby providing a rotatable coupling between the screw fastener and the graft  1470 . The saddle  1450  and loop element  1460  can be located in the passageway  1430  by passing them though the opening at the proximal end  1040 . 
     By way of example only, the combination saddle and loop can comprise a loop having an expanded substantially non-compressible end, such that the material and configuration were sufficiently non-compressible that the expanded end would not pass though the necking down  1449  of the passageway  1430 . 
     By way of example only an expansion the looped material can be in the form of a tight weave, a specialised knot or treatment of the loop material in such a way that it is restricted from pass though the necking down  1449  of the passageway  1430 , but still enabled to rotate within the passageway  1430   
       FIG. 14C  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention. 
     In this embodiment, the graft  1470  is received by the portal  1047  and extend around the saddle  1450 . The free ends of tendons define the second end of the graft. A saddle  1450  is adapted to rotate freely within the passageway thereby providing a rotatable coupling between the screw fastener and the graft  1470 . The saddle  1450  and tendons /graft  1470  can be located in the passageway  1430  by passing them though the opening at the proximal end  1040 . 
     By way of example an artificial graft can be combined from multiple artificial tendon strands that extend around the saddle and are braded in situ, for providing a rotatable coupling to the screw fastener. 
       FIG. 14D  is a sectional view of an embodiment fastener made in accordance with the teachings of the present invention. 
     In this embodiment, when performing a bone ligament reconstruction, a webbing configuration, grabbing suture configuration, trap type configuration, or the like  1460  can be used to couple bone  1472  at the first end of the transplanted tendon/graft  1470 . The configuration can be extend around the saddle, thereby providing a rotatable coupling to the screw fastener 
     Referring to  FIG. 15A  though  15 D, a method of using a fastener in an ACL reconstruction is disclosed. 
       FIG. 15A  shows holes are first drilled in the femur  1510  and tibia  1520  to form a femoral tunnel  1512  and tibial tunnel  1522 . 
       FIG. 15B  shows that a driver  1530  can be passed through either tunnel ( 1512  or  1522 ), in any direction. The screw fastener  1540  can be prefixed on the driver or placed in position once the driver is passed through the holes. The tendons/graft  1550  can be rotatably coupled to the screw fastener  1540 , for example by passing the to the tendons/graft through a loop  1542  located about a saddle (not shown). The driver can then be pulled up though the tunnel (as indicated by arrow  1532 ) such that the screw fastener engages the bone. 
       FIG. 15C  shows that as the driver  1530  and coupled screw fastener (not shown) can be rotated (as indicated by arrow  1534 ) with respect to the respective bone. This causes the screw fastener to threadedly engage the bone and thereby draw the tendons/graft  1550  up though the tunnel (as indicated by arrow  1554 ). In this embodiment, the saddle rotates within the screw as the graft is being pulled up so as to not twist the graft. The opposite end of the graft  1552  is fixed relative to the tibia  1520 . By way of example only, an end plug  1560  can be fixed opposite end of the graft  1552 , such that drawing up the graft bring the end plug  1560  into abutting engagement (or seated) with the tibia  1520 . It will be appreciated that the opposite end  1552  of the tendons/graft  1550  to the screw (or the tendons/graft free end) can be fixed in any surgically suitable manner. 
       FIG. 15D  shows that once the opposite end  1552  of the graft is fixed relative to the tibia  1520 , the driver  1530  and coupled screw fastener (not shown) can be rotated in a clockwise or anticlockwise direction with respect to the respective bone (as indicated by arrow  1536 ). This causes the screw fastener to threadedly engage the bone and thereby increases or decreases tension applied to tendons/graft  1550  (as indicated by arrow  1556 ). A torque driver can be used to fine tuned the tension applied to the tendons/graft  1550 . 
     The driver  1530  can then be detached from the screw fastener  1540 . 
     Referring to  FIG. 16 , a method  1600  of using a fastener in an ACL reconstruction can comprise the steps of:
         STEP  1610 : providing a femoral tunnel and a tibial tunnel in the femur and tibia respectively;   STEP  1620 : coupling a screw fastener to a driver passed through either tunnel;   STEP  1630 : rotatably coupling a graft to the screw fastener;   STEP  1640 : pulling up the screw fastener engages a bone;   STEP  1650 : rotating the screw fastener, by rotating the driver, causing the screw fastener to threadedly engage the bone and thereby draw the graft up though the tunnel.   STEP  1660 : fixing the opposite end of the graft to the screw (or the tendons/graft free end) to a bone using a suitable surgical manner;   STEP  1670 : with the opposite end of the graft fixed relative to a bone, the screw fastener (and coupled driver) can be rotated in a clockwise or anticlockwise direction with respect to a respective bone to thereby increase or decrease tension applied to tendons/graft.   STEP  1680 : detaching the screw fastener from the driver.       

     In this embodiment, a saddle rotates within the screw as the tendons/graft is being pulled up so as to not twist the graft. The opposite end of the graft can be fixed relative to the tibia. By way of example only, an end plug can be fixed to the opposite end of the graft, such that drawing up the graft bring the end plug into abutting engagement (or seated) with the tibia. It will be appreciated that the opposite end of the graft to the screw (or the tendons/graft free end) can be fixed in any surgically suitable manner. 
     While the present invention has been disclosed with reference to particular details of construction, these should be understood as having been provided by way of example and not as limitations to the scope or spirit of the invention. 
     Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments. 
     In the claims below and the description herein, any one of the terms comprising, comprised of or which comprises is an open term that means including at least the elements/features that follow, but not excluding others. Thus, the term comprising, when used in the claims, should not be interpreted as being limitative to the means or elements or steps listed thereafter. For example, the scope of the expression a device comprising A and B should not be limited to devices consisting only of elements A and B. Any one of the terms including or which includes or that includes as used herein is also an open term that also means including at least the elements/features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising. 
     Similarly, it is to be noticed that the term coupled, when used in the claims, should not be interpreted as being limitative to direct connections only. The terms “coupled” and “connected”, along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Thus, the scope of the expression a device A coupled to a device B should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means. “Coupled” may mean that two or more elements are either in direct physical, or that two or more elements are not in direct contact with each other but yet still co-operate or interact with each other. 
     As used herein, unless otherwise specified the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner. 
     As used herein, unless otherwise specified the use of terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader, or with reference to the orientation of the structure during nominal use, as appropriate. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate. 
     Similarly it should be appreciated that in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention. 
     Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination. 
     Furthermore, some of the embodiments are described herein as a method or combination of elements of a method that can be implemented by a processor of a computer system or by other means of carrying out the function. Thus, a processor with the necessary instructions for carrying out such a method or element of a method forms a means for carrying out the method or element of a method. Furthermore, an element described herein of an apparatus embodiment is an example of a means for carrying out the function performed by the element for the purpose of carrying out the invention. 
     In the description provided herein, numerous specific details are set forth. 
     However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. 
     Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described within the scope of the present invention.