Abstract:
Devices for dispensing suture threads and/or suture threads with needles attached to them that are particularly useful for inserting surgical implants, such as suture anchors, that make use of sutures. The devices use a novel spool design to safely and neatly hold the suture thread and/or needles until the surgeon wishes to dispense them.

Description:
FIELD OF THE INVENTION  
         [0001]    The device of the present invention is useful for holding and dispensing suture thread and suture thread with needles. It is particularly useful incorporated into a novel device and method for implanting suture anchors or other surgical implants in body tissue. More specifically, the present invention relates to devices that include a spool on which sutures and/or suture needles are wound.  
         BACKGROUND OF THE INVENTION  
         [0002]    Often, doctors have to attach various soft tissues, such as tendons and ligaments, to hard tissue, such as bone. To provide an alternative to suturing the tissue directly through tunnels in the bone, suture anchors have been developed to aid in the attachment of soft tissue to bone. Generally, the doctor will attach such soft tissue to bone by suturing the soft tissue to a suture anchor that has been placed in the bone. During this suturing procedure, the surgeon must pass a suture through the tissue to be repaired, attach it to the suture anchor, and knot the suture so that the tissue is securely fastened to the suture anchor. Often, the suture anchor is prepackaged with sutures and possibly pre-attached needles, thereby obviating the need for the surgeon to pass sutures through the suture anchor himself.  
           [0003]    The suture anchor and corresponding sutures are delivered by any number of devices currently commercially available from manufacturers such as Mitek and Arthrex. Typically, the delivery device includes a handle, shaft, suture anchor, and sutures, possibly with needles. The handle is attached to the proximal end of the shaft and the suture anchor is attached to the distal end of the shaft.  
           [0004]    The sutures are often attached in some way to the handle or enclosed within it. When the sutures and/or needles are not contained within the handle of the insertion device (for instance, when they are held in a separate tray) the surgeon often has to use two hands to remove the suture and needles from the tray. This can be difficult to accomplish while also holding the insertion instrument. Alternatively, each end of a given suture may have a needle attached thereto, all of which are attached or enclosed within the handle. The suture lengths run along the shaft from the proximal end to the distal end and are threaded through the suture anchor attached to the distal end of the shaft. Often, in these prior art devices, the preattached sutures are easily tangled with each other, adding difficulty and time to the operation, or cannot be dispensed from the handle with only one hand. Further, in the situations in which both sutures and needles are contained in the handle of the device, the needles get entangled with the sutures, or alternatively, must be removed from the handle and/or passed through the shaft of the device, which can be difficult, time consuming, or require two hands to accomplish.  
           [0005]    Thus, there is a need in the prior art for a device for inserting suture anchors and/or other suture-containing implants into the body that provides a simple way to insert the implant without tangling the sutures and/or needles.  
         SUMMARY OF THE INVENTION  
         [0006]    The devices of the present invention are useful for holding and dispensing suture thread and suture thread with attached needles. They contain a handle or base with a spool rotatably attached to it, around which the suture thread and needle is wound. In preferred embodiments, the suture thread is dispensed from grooves encircling the spool. Further, in certain preferred embodiments, the handle is capable of contacting or engaging the spool such that at times, the spool cannot rotate so as to unwind the suture. Thus, the suture thread does not unintentionally unwind from the spool. In certain preferred embodiments, the spool contains separate slots for needles that are attached to the suture thread. In still other preferred embodiments of the present invention, the spool contains indentations that are designed to hold and secure the suture thread on the spool so that it does not become tangled or unintentionally unwind from the spool. However, these indentations allow the suture to be released from the suture when desired.  
           [0007]    Embodiments of the present invention are particularly advantageous as devices for inserting suture anchors or other surgical implants that make use of suture thread. The devices comprise a handle attached to a longitudinal shaft. The distal end of the shaft holds the surgical implant. Attached to the handle is a spool around which the ends of at least one suture thread is wound, preferably in separate grooves that encircle the surface of the spool. The thread travels from the spool to the distal end of the shaft, where it is threaded through (attached to) the surgical implant. The spool allows for the convenient dispensing of the suture thread, with the use of only one hand, and a low likelihood of tangles in the thread.  
           [0008]    In certain preferred embodiments, the device contains two separate suture threads, each of which is threaded through the surgical implant. The two threads preferably are threaded through different eyelets in the surgical implant, so that the tying of knots in one suture thread does not affect the movement of the other suture thread. Where there are two suture threads, the spool preferably has four separate grooves, one for each of the suture ends. These grooves help to keep the suture ends from tangling during the insertion of the surgical implant.  
           [0009]    In another preferred embodiment, needles are pre-attached to the ends of the suture thread. The needles, which are curved and roughly semicircular in shape, also fit around the spool. The suture thread can be wound around the spool over the needles, or, in a preferred embodiment, the needles are held on the spool in separate slots. Preferably, at least a portion of the slots containing the needles is located under the surface of the spool. The sharp tip of the needles can be located in this portion of the slot, which serves both to help prevent unwanted movement of the needles on the spool, and also lessens the likelihood of the surgeon or other hospital personnel being stuck by a needle.  
           [0010]    The spool also preferably has indentations which are capable of securing the suture thread, thereby helping to prevent unwanted movement of the needles and the suture thread on the spool. In embodiments where the needles are located in the same grooves as the suture thread, and the suture thread is wound around the spool on top of the needles indentations for holding the suture threads may be located at the bottom of the grooves. In embodiments where the needles are located in separate slots that are adjacent to the grooves where the thread is wound, the indentations for holding the thread are preferably located adjacent to the slots. While these indentations serve to hold the suture thread in place, they also allow the suture thread to be unwound from the spool when desired. In other words, the surgeon can easily remove the sutures from these indentations when desired.  
           [0011]    In yet another preferred embodiment of the present invention, the spool will rotate in a direction that will cause the suture thread to unwind only when desired by the surgeon. This can preferably be achieved by a portion of the handle temporarily contacting or engaging the spool, thereby preventing the unwanted rotation or unwinding of the suture thread. When the surgeon wishes to allow the suture thread to unwind from the spool, he releases the contact between the handle and the spool, thereby allowing the spool to rotate freely. This prevents unwanted slack in the suture thread during the insertion of the surgical device, and helps to prevent tangling of the suture thread. The tautness of the suture thread also helps to keep the anchor suture positioned on the distal end of the shaft of the device. It is further preferable that the particular mechanism used to prevent the unwinding of the suture thread can be disengaged with only one hand, allowing the surgeon one free hand.  
           [0012]    In certain preferred embodiments, the spool is located inside the handle of the device. In such embodiments, the handle may have a door that, when closed, contacts the spool, preventing its motion in the direction that would cause the suture thread to unwind. This contact is preferably caused by a protuberance on the inside of the door that engages one of a series of notches (indentations) or teeth, on the spool. When the door is opened, preferably by pivoting, rotating, or sliding it open, the spool is no longer engaged by the door and can freely rotate.  
           [0013]    The distal end of the shaft preferably contains a recess for holding at least the proximal portion of the surgical implant. In a further preferred embodiment, the distal end of the shaft contains a longitudinal slot extending from the distal tip of the shaft towards the proximal (handle) end of the shaft. The suture threads may be positioned within this slot, thereby helping to keep the threads away from the distal tip of the shaft during the insertion of the surgical implant, and allowing the threads to help keep the implant properly positioned on the distal end of the shaft. Once the implant is inserted into the tissue being repaired, however, the slot allows the thread to pass completely outside of the shaft, allowing the surgeon to easily unwind the thread and any needles from the spool.  
           [0014]    While the devices of the present invention may be used to insert any surgical implant that makes use of suture thread, it is most preferably used for inserting suture anchors. These suture anchors are preferably screwed into the tissue to be repaired, by rotating the handle and shaft as one would a screwdriver, or may be pushed into the tissue to be repaired, even by tapping the end of the device with a mallet or hammer, to force the suture anchor into the tissue to be repaired. However, in either case, once the suture anchor is inserted into the tissue to be repaired, it is easily removed from the distal end of the shaft, preferably simply by pulling the shaft away from the inserted implant.  
           [0015]    The present invention also includes methods for inserting surgical implants in vivo using the aforementioned devices. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 shows a perspective view of an embodiment of a spool used in the present invention.  
         [0017]    [0017]FIG. 2 shows an embodiment of the present invention useful for inserting suture anchors in vivo.  
         [0018]    [0018]FIG. 3 shows an exploded view of the embodiment of FIG. 2.  
         [0019]    [0019]FIG. 4 shows a side view of the distal end of the embodiment of FIG. 2.  
         [0020]    FIGS.  5 - 9  show side views of an embodiment of the present invention during various stages of its use in a surgical procedure to insert a suture anchor. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    The present invention provides an apparatus that, e.g., allows convenient placement of suture anchors or other devices that use suture thread to attach body tissue to body tissue or to bone.  
         [0022]    The present invention uses a novel spool system that secures sutures and even needles attached to the sutures, and allows for easy delivery of them by a surgeon. The spool allows the suture to be delivered quickly with little risk of tangling, and little risk of accidentally getting stuck with the needles. FIG. 1 shows a preferred embodiment of the spool  1  used in the present invention around which sutures  6  and suture needles  7  may be wound.  
         [0023]    In the particular embodiment of FIG. 1, the spool  1  is a cylinder shaped member, which is capable of rotating around a central axis  5 . The spool  1  has several grooves  2  encircling its surface, for receiving suture thread. There preferably is a separate groove  2  for each end of the suture thread being dispensed. Thus, for a spool that dispenses two separate suture threads, there are preferably four grooves  2  for receiving the ends of each of the two suture threads. The separate grooves for each end of the suture thread helps to prevent tangling of the suture threads. The grooves  2  are preferably deep enough so that the suture thread may be wound around the spool  1  while remaining inside the groove  2 . Again this helps keep the suture thread in the groove  2 , which helps to prevent tangling of the suture. While the embodiment of FIG. 1 has four grooves  2  for receiving the ends of two separate suture threads, other embodiments could have a different number of grooves for accommodating one or more suture threads.  
         [0024]    In the particular preferred embodiment of FIG. 1, the spool  1  also has slots  3  for holding needles that are attached to the ends of the suture threads. Each slot  3  is preferably adjacent to a groove  2 , so that the needle that is attached to a particular suture thread is located on the spool  1  next to the suture thread itself. A portion of the slot  3  preferably tunnels under the surface of the spool  1  (i.e., leads to a recess under the surface of the spool  1 ), and holds the sharp tip of the needle. This helps to keep the needle from moving from the slot  3 , and also helps prevent hospital personnel from accidentally sticking themselves with the suture needles. The slot  3  is preferably as deep as the width of the needle, so that the needle can be stored completely within the slot  3 . In FIG. 1, one of the slots  3  has a needle  7  located within it. As can be seen in FIG. 1, the slot is deep enough to hold the needle  7 .  
         [0025]    The suture needles that are used with the present invention are generally curved into a semicircular shape, and therefore may be placed around the spool. While it is preferred, there need not be separate slots for the needles on the spool. The needles could be located, e.g., at the bottom of the grooves  2 , with the suture thread wound around the spool  1  in the groove on top of the needle. This may result in the diameter of the spool being larger, however.  
         [0026]    In the preferred embodiment of FIG. 1, there are also indentations  4  for securing the suture thread. In FIG. 1, the indentations are located on the surface of the spool  1 , adjacent to the slots  3  which hold the needles that may be attached to the sutures. The suture thread is pushed into the indentation  4 , which then helps to hold the suture thread in place. Due to the placement of the indentations  4 , this also helps to hold the needles in place. In the embodiment of FIG. 1, the indentations  4  are narrower at the top than at the bottom, and are tear-drop shaped. Preferably the narrow portion of the indentation is slightly smaller than the width of the suture thread, so that the suture thread (being somewhat compressible) can be pushed through the narrow portion of the indentation  4 , and will likely remain in the wider portion of the indentation  4  until removed by the surgeon. Thus, the indentation  4  secures the suture thread. Other shapes for the indentation  4  can be used as part of the present invention. Moreover, the sutures can be held in place with structures other than simple indentations, such as a variety of clasps. While not shown in FIG. 1, the spool  1  could also include indentations or other mechanisms for holding the needles themselves in place, instead of or in addition to the indentations or other mechanisms for holding the suture threads in place.  
         [0027]    In the situation where suture needles are located in the same grooves as the suture thread, indentations or other mechanisms for securing the suture thread may be located at the bottom of the grooves, adjacent to the needles. This would help to prevent the needle from accidentally falling off the spool when the suture thread is being unwound.  
         [0028]    Also shown in FIG. 1 are a series of triangular notches  20  encircling the circumference of the spool. These notches  20  are designed to temporarily contact a movable protuberance on the handle or base to which the spool  1  is attached, thereby preventing the spool  1  from rotating in the direction that would cause the suture thread to unwind from the spool  1 . When the contact between the handle or base and the spool is released, the spool can rotate freely. This mechanism helps to prevent unwanted or unintended unwinding of the suture thread. While, in FIG. 1, the notches  20  are located in the center of the spool  1 , they could be towards the sides of the spool  1 , or even on the sides of the spool  1 . Further, there need not be a series of triangular notches. There could be only one notch of a variety of shapes. Further, there could be a protuberance, instead of a notch, that contacts the handle or base to which the spool is attached and prevents the rotation of the spool in the direction that would cause the suture thread to unwind. In other embodiments, there need be no special indentation or protuberance, or series of indentations or protuberances on the spool to prevent the unwanted rotation, so long as some portion of the handle or base makes suitable contact with some portion of the spool.  
         [0029]    The spool is preferably made out of molded plastic, but can be made of other materials, or through other well-known manufacturing techniques. A benefit of molded plastic is that it allows the spool to be manufactured inexpensively.  
         [0030]    [0030]FIG. 2 shows an embodiment of a device of the present invention for inserting suture anchors that uses the spool shown in FIG. 1. The device has a handle  8 . Attached to the distal end of the handle is a longitudinal shaft  9 . In the embodiment of FIG. 2, the spool  1  is located inside the handle  8 . In other embodiments of the present invention, the spool can be attached to the exterior of the handle. Having the spool enclosed within the handle allows the handle to be easily gripped and rotated by the surgeon, and also lessens the likelihood that the sutures wound around the handle will be tangled or disturbed. Further, if the sutures have needles attached to them, the location of the spool inside the handle helps to lessen the likelihood of surgical personnel being unintentionally stuck by the needles.  
         [0031]    In the embodiment of FIG. 2, the handle  8  has a door portion  11 , which allows access to the spool  1 . An extension  12  of the door portion  11  extends beyond the side of the handle  8 , allowing the door portion  11  to be opened with the same hand the surgeon is using to hold the handle  8 . While the door portion  11  pivots open in the embodiment of FIG. 2, it could be opened in other ways, such as by rotating or by sliding.  
         [0032]    The suture threads  6  can be seen exiting the handle  8  and traveling to the distal end of the shaft  9 , where the suture anchor  10  is located. The suture threads are threaded through (attached to) the suture anchor  10 .  
         [0033]    [0033]FIG. 3 shows an exploded view of the embodiment of FIG. 2. In FIG. 3, the interior chamber  13  of the handle  8 , where the spool  1  is placed, can be seen, because the door portion  11  and a handle cover  14  are shown removed from the handle  8 . The underside of the door portion  11  contains a protuberance (not seen) that contacts one of the series of triangular notches  20  located on the spool  1  when the door portion  11  is closed. When the door portion  11  is closed (as shown in FIG. 2), the spool  1  is prevented from rotating in the direction that would cause the suture thread to unwind by the contact between the door portion  11  and the spool  1 . When the door portion  11  is opened, then it no longer contacts the spool  1 , and the spool  1  may rotate freely, allowing the surgeon to unwind the suture thread.  
         [0034]    The contact between the door portion  11  and the spool  1  need not be the result of a protuberance on the interior of the door portion  11  contacting one of a series of notches  20  in the center of the spool  1 . Any type of temporary contact between the door portion  11  and any part of the spool  1  could act to prevent unwanted rotation of the spool  1 . Further, while in FIGS. 2 and 3, the door portion  11  is pivoted open to release the contact between it and the spool  1 , the contact could be released in several different ways. For instance, the door portion  11  could slide or rotate, thereby releasing the contact between it and the spool  1 . Further, there could be a button, switch, or lever on the handle  8  that the surgeon presses or moves to release the contact with the spool  1  that is preventing unwanted rotation of the spool.  
         [0035]    Further, the spool  1  could have temporary contact with a part of the handle  8  other than the door portion  11  to prevent unwanted rotation of the spool  1 . This could be the case, for instance, in embodiments where the spool is not located inside of the handle. Such contact could be disengaged, thereby allowing the spool to rotate freely, by pivoting, sliding, rotating, or otherwise moving the portion of the handle that is in contact with the spool, or even by moving the spool itself. Further, the contact with the spool could be released by the surgeon pressing a button or moving a switch or lever which in turn releases the contact between the spool and the handle that prevents the unwanted rotation of the spool. The means for preventing the rotation of the spool thus can include any means for providing temporary contact with the spool, provided that the contact is sufficient to prevent the spool from rotating at least in the direction that would cause the suture thread to unwind.  
         [0036]    [0036]FIG. 4 shows a close-up view of the distal portion of the shaft  9  of the device of FIG. 2, with the suture anchor  10  positioned slightly away from the shaft  9 . As can be seen, the suture threads  6  are threaded through the suture anchor  10 . In a preferred embodiment, each suture thread is threaded through a different hole  17  of the suture anchor  10 , so that the threads move more independently of each other when eventually being tied by the surgeon. Thus, in the embodiment of FIG. 4, there are two suture threads and the suture anchor  10  has two holes  17 , each for receiving one of the suture threads. Nevertheless, the suture anchor need not have a separate hole for each suture thread, particularly in very small suture anchors.  
         [0037]    In the embodiment of FIG. 4, the suture anchor  10  has screw threads  16 . This allows the suture anchor  10  to be screwed into the tissue to be repaired by the surgeon. In this embodiment, the handle and shaft of the device are used as a screwdriver to insert the suture anchor. Depending on the area to be treated, the surgeon may screw the suture anchor into a predrilled hole. In other embodiments, the insertion device of the present invention may be used to insert suture anchors or other surgical implants in different ways, such as by pushing them, or even allowing them to be hammered into the tissue to be repaired.  
         [0038]    The suture anchors used with the present invention are preferably made of self-reinforced bioabsorbable polymeric material, as described, for instance, in U.S. Pat. No. 4,968,317, which is hereby incorporated fully by reference. One material that is particularly useful for making suture anchors that can be used with the present invention is self-reinforced (96/4D) PLA copolymer.  
         [0039]    In the preferred embodiment of FIG. 4, the distal portion of the shaft  9  contains a recess  18 , into which the proximal portion of the suture anchor  10  can be securely placed. The suture anchor  10  is held securely in the recess until the suture anchor  10  is inserted in the tissue to be repaired, at which time the suture anchor  10  may be easily removed from the recess  18  in the distal portion of the shaft  9  by simply pulling the shaft  9  away from the suture anchor  10 . The closer the interior dimensions of the recess  18  are to the exterior dimensions of the proximal end of the suture anchor  10 , the more securely the suture anchor  10  will be held in the recess  18 . In certain preferred embodiments, the suture anchor  10  is also held securely on the distal portion of the shaft  9  as a result of the taut suture threads  6 , which prevent the suture anchor  10  from moving distally away from the shaft  9  until the surgeon releases the spool.  
         [0040]    As shown in FIG. 4, in a preferred embodiment of the present invention, the distal portion of the shaft  9  contains a slot  15 . The slot  15  extends from the distal tip of the shaft  9  towards the proximal (handle) end of the shaft. The suture threads  6  travel from the spool—located in, on, or near the handle of the device—outside the shaft to the slot  15 , where the suture threads enter the slot  15 , and the recess  18 , where the suture anchor  10  is located. In the preferred embodiment of FIG. 4, the slot  15  is wider at its proximal end than at its distal end. This helps provide room for the suture threads  6  at the proximal area where they enter the slot  15 , yet helps to prevent the threads  6  from exiting the slot  15  completely before the surgeon implants the suture anchor  10  in the tissue to be repaired. Once the suture anchor  10  is inserted in the tissue to be repaired, the slot  15  allows the surgeon to completely remove the suture thread from the shaft  9 , simply by pulling the distal portion of the thread through the slot  15 , thereby releasing it entirely from the shaft  9 . If the slot  15  did not extend all the way to the distal end of the shaft  9 , this would not be possible and the suture thread, and any needles attached thereto, would have to be passed in their entirety through the slot  15  in the shaft  9 . While in FIG. 4, the suture threads are located outside of the shaft until they enter the slot  15 , in other embodiments of the present invention, the suture threads may travel from the spool to the implant through the entire length of the shaft.  
         [0041]    [0041]FIG. 5 shows the preferred embodiment of FIG. 2 being used to insert a suture anchor  10  into bone  19 . The suture anchor  10  has been screwed into the bone  19  through a precut channel. The suture threads  6  are running along the outside of the shaft  9 , and pass through the slot  15 , where they are threaded through the suture anchor  10 . For ease of reference by the surgeon, when two separate suture threads are used with the device of the present invention, it is preferable that they are different colors.  
         [0042]    [0042]FIG. 6 shows the surgeon opening the door portion  11  of the handle  8  with the hand that is holding the handle  8 , by pushing his thumb against the extension  12  of the door portion  11  that extends beyond the side of the handle  8 . This causes the door portion  11  to disengage its contact with the spool, thereby allowing the spool to rotate freely and allowing the suture threads  6  to unwind from the spool.  
         [0043]    [0043]FIG. 7 shows the surgeon pulling the device away from the inserted suture anchor. As the surgeon pulls the device away from the suture anchor, the suture threads  6  have slipped through the slot  15  and are completely external to the shaft  9 . The suture threads  6  are unwinding from the spool  1 , which is free to rotate now that the door portion  11  is opened. Once the suture thread has completely unwound, the needles will be released from the spool.  
         [0044]    [0044]FIG. 8 shows the implanted suture anchor  10 . Its screw threads  16  are holding it securely in the bone  19  into which it has been inserted. The suture threads  6  are still attached to the suture anchor  10 .  
         [0045]    [0045]FIG. 9 shows the suture threads  6 , with their attached needles  7  after they have been completely unwound and removed from the spool of the device. At this point, the threads, which are not tangled, may be passed through body tissue and knotted so as to effect the surgical repair being performed, e.g., the attachment of tendon to bone. While in the embodiment shown in FIG. 9 the sutures have needles attached to their ends, the suture threads used in conjunction with the present invention need not have needles pre-attached to them.  
         [0046]    After the description above of the present invention and certain specific embodiments thereof, it will be readily apparent to those skilled in the art that many variations and modifications may be made to the present invention without departing from the spirit and scope thereof.