Abstract:
Disclosed is a device and method for repairing a partially or totally ruptured tendon. The device comprises an implant placed inside or outside of the tendon on either side of the rupture in order to strengthen the ruptured area during repair. Once positioned inside the tendon, the tendon is held in place so it can heal either by sewing or stapling through the tendon and implant, or by any other suitable method that utilizes the implant to provide strength to the ruptured area. In this manner the tendon can heal with less chance of rupturing again prior to healing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application in a continuation of U.S. patent application Ser. No. 13/648,019 entitled “DEVICES AND METHODS FOR TENDON REPAIR,” filed on Oct. 9, 2012, which claims priority to U.S. Provisional Patent Application Ser. No. 61/589,526 entitled “TENDON REPAIR DEVICE AND METHOD,” filed on Jan. 23, 2012, the disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a device and method for repairing a ruptured tendon that reduces the likelihood of the tendon being partially or completely ruptured again while healing. 
     BACKGROUND OF THE INVENTION 
     When a tendon is partially or totally ruptured or severed (collectively, “a rupture”), the two ends of the tendon where the rupture occurred are reattached surgically. In practice, this is accomplished by a surgeon stitching (i.e., suturing) the two ends together. The suturing can be done in any suitable manner, as there have been many demonstrated techniques of suture repair. A problem with these standard suture techniques is that the sutured tendon is relatively weak until the tendon is fully healed and the tendon can rupture if the force applied to the repaired tendon exceeds the strength of the repair. 
     SUMMARY OF THE INVENTION 
     The invention comprises an implant placed inside or outside a ruptured tendon on both sides of the rupture in order to strengthen the tendon repair of the ruptured area during healing. Once positioned inside or outside the tendon the implant and tendon are secured together by sewing or stapling through the tendon and implant, or by any other suitable method (including staples, tacks or rivets) that utilizes the implant to provide strength to the ruptured area. In this manner the tendon can heal with less chance of rupturing again prior to healing. 
     Instead of an internal implant, each end of the ruptured tendon may be positioned inside a tube (or other type of external implant) and retained there in order for the tendon to heal. Again, the material forming the external implant adds strength to the ruptured area to help prevent the tendon from rupturing again prior to healing. The tendon and external implant can be secured together by any physical means, such as those as noted above. 
     Methods of using tendon repair devices according to the invention are also disclosed herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an embodiment of a device according to the invention. 
         FIGS. 2A-2C  show an embodiment of a needle according to the invention. 
         FIG. 3A-3D  show various implants having surface textures and material configurations according to aspects of the invention. 
         FIG. 4  depicts the first step in positioning a device according to the invention in a ruptured tendon. 
         FIG. 5  depicts a second step in positioning a device according to the invention in a ruptured tendon. 
         FIGS. 6A-6C  depicts a third step in positioning a device according to the invention in a ruptured tendon. 
         FIG. 7  depicts a fourth step in positioning a device according to the invention in a ruptured tendon. 
         FIG. 8  depicts a needle according to the invention. 
         FIG. 9  shows an embodiment wherein needles or spikes are used to temporarily or permanently secure the ruptured area of a tendon in place. 
         FIG. 10  shows rivets that could be used to secure an insert in place in a tendon for repair. 
         FIG. 11  shows rivets of the type shown in  FIG. 10  that could be used to secure an insert inside of or outside of a tendon. 
         FIG. 12  shows another type of fastener that may be used to secure an insert inside of or outside of a tendon. 
         FIG. 13  shows a tendon that is first secured over spikes or needles and a knife that goes through the tendon to pull an insert through the tendon and the rupture. 
         FIG. 14  shows an insert according to an aspect of the invention that includes directional barbs that help prevent the insert from being dislodged from the tendon. 
         FIG. 15  shows an alternative shaped insert that may be used inside of a tendon. 
         FIG. 16  shows an insert that is positioned outside of the tendon. 
         FIG. 17  shows two cross-sectional views of inserts that may be positioned outside of a tendon. 
         FIG. 17A  is a view of an embodiment of the insert of  FIG. 16  laid out flat to show its interior surface. 
         FIGS. 18-20  show different embodiments of an insert that may be used inside of a tendon. 
         FIGS. 21 and 22  show a clamp and tool used to position and crimp the clamp that can be used to secure an insert according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Turning now to the Figures, where the purpose is to describe a preferred embodiment of the invention and not to limit same,  FIG. 1  shows a tendon repair device  10  according to an aspect of the invention. Device  10  has a support implant  11  having a body portion  12 , with a first end  12 A and second end  12 B. The function of support implant  11  is to be inserted into each end of a ruptured tendon  1  so as strengthen the repair to the rupture in order to help prevent the tendon from rupturing again prior to healing. Once ruptured, the tendon has a first end  2  and another, second end  4 . The two ends must be connected to repair the rupture. 
     Implant  11  can be formed of any suitable bio-absorbable or non-bio-absorbable material, and Implant may be a mesh like or cloth like, flexible material. Textured edges, scalloping or other physical characteristics may be present on implant  11  to increase its friction with the tendon to help prevent slippage. For example, implant  11  may have an outer surface having one of a: spiraled configuration, a cruciate cross section, and a plurality of outwardly-extending ribs. 
     In one preferred embodiment, implant  11  comprises standard suture material, which is either absorbable or nonabsorbable. Such material includes threads that may be monofilament or polyfilament braid or weave formed in approximately a 6 cm×3 mm mesh. The insert may be tubular, or generally flat, or of any suitable configuration. 
     Exemplary embodiments of implants according to various aspects of the invention may include a fabric material. Such fabric material may be woven, knitted, braided, and/or twisted. The fabric may comprise any desired combination of absorbable and non-absorbable materials, including silk, cotton, metal, and/or synthetic fibers. The fabric may be of any suitable size, shape, thickness, and density. 
     Examples of absorbable materials that may be used in conjunction with embodiments of the invention include polyglactin, polycaprolate, poliglecaprone, polysorb, polyglygolic acid, polylactic acid, polydioxanone, caprolactone, collagen, surgical gut, and combinations thereof. Examples of non-absorbable materials that may be used in conjunction with embodiments of the invention include polypropylene, polyester, nylon, silk, cotton, metal, and combinations thereof. 
     The implant  11  could also be pretreated with an antibiotic or growth enhancing substance. There are many commercially-available pharmacological agents such as antibiotics and therapeutic agents such as growth hormones and/or bioactive molecules that may accelerate tendon healing. Additionally, non-bioactive products may be incorporated into the implant to physically strengthen the repair. 
     In the preferred embodiment, end  12 A and  12 B are each attached to a separate needle  14 . Each needle  14  is for being inserted into one of the ends of the ruptured tendon  1  and to pull body portion  12  of implant  11  into the first end  2  of the tendon and the second end  4  of the tendon, respectively. Any suitable needle or other device may be used for this purpose. It is preferred, however, that the needle have a shape that predetermines how far it penetrates along the length of each end of the tendon  1 . In the embodiment shown, each needle  14  has a relatively straight portion  14 A and a curved portion  14 B, as best seen in  FIGS. 1 and 8 . Other devices for insertion of an insert  11  could be used, such as reamers designed to open a path in the tendon for insert placement. 
     The size and shape of needle  14  is determined by the size and shape of the particular implant. In this current depiction, the dimensions of needle  14  are 2 cm in length and 3 mm wide at the portion to which the implant  11  is attached. The size and shape of needle  14  depends on the size of the tendon to be repaired and the type of implant used to support the ruptured area of the tendon. Different needle lengths and sizes may be required for different size tendons and different space requirements within the body. 
     Implant  11  has an outer surface  16 . Outer surface  16  preferably has a surface that creates friction with the inner part of the tendon  1 , which outer surface  16  will contact when inserted into tendon  1 . The purpose of the friction is to bind implant  11  with the tendon to help insure the two do not separate and thus to help strengthen the support provided by implant  11  at the rupture site. 
     The outer surface  16  of implant  11  may have any one of or combination of configurations to create friction. In the embodiment shown in  FIG. 3A  the outer surface includes stiplets  18 . In a preferred embodiment, the stiplets  18  are between 1 mm and 2 mm in height (as measured according to the distance from the main portion  16 A of the outer surface), and most preferably about 0.5-2 mm in height. The size of the stiplets may vary, however, according to the size of the tendon and type of rupture being repaired. For example, the stiplets may be between 0.5 mm and 4 mm in height and between 0.5 mm and 4 mm in diameter at the base. 
     It is preferred that each stiplet  18  is between 0.5-5 mm in distance from the next closest stiplet  18 , although any suitable distance may be selected. The implant could resemble a string of pearls (as shown in  FIGS. 3B and 15 ) which would have relatively large variations between the larger stiplets and the smaller size of the implant between the stiplets. It is also possible that implant  11  could have a co-figuration such as a stiplets on a tape strip or cord that might be, for example, 3 mm wide by 1 mm thick and have with stiplets on either or both sides, or have a top and/or bottom surface that is microtextured in any manner, and may simply be the surface of a coarse, braided cloth material. 
       FIGS. 3B and 3C  show implants that have ribbed outer surfaces. In  FIG. 3B  the diameter of the main portion  16 B of the outer surface is relatively narrow, and each rib  20  has a height of approximately 0.5 mm as measured from the main portion  16 B, although any suitable height may be utilized, such as between 1 mm-8 mm. 
     In  FIG. 3C  the diameter of the main portion  16 C is larger than the diameter of main portion  16 B, and each rib  22  has a height of approximately 0.5 mm as measured from the main portion  16 C, although any suitable height may be utilized, such as between 1 mm-8 mm. 
       FIG. 3D  shows an implant with a serpentine outer wall  16 D. In this embodiment, the variation between the smallest diameter of the implant and the lowest is about 0.5 mm to about 4 mm, although any suitable dimensions, for example between 1 mm and 2 mm to 5 mm, or 2 mm and 3 mm to 5 mm, may be used. 
     It is also possible to combine any of the concepts shown in  FIGS. 3A-3D, 14 and 15 . For example, the implant  11  could have a serpentine outer wall and also include stiplets and/or ribs. Further, the implant may include backward angled barbs that allow the implant to be pulled through the tendon, but that resist removal when pulled in a direction against the barbs, as shown in  FIG. 14 . 
     Once the implant  11  in positioned into each end  2  and  4  of the ruptured tendon  1 , the two ends  2  and  4  of the tendon  1  and the implant  11  are mechanically attached in any suitable manner, such as by suturing, stapling, or using surgical rivets or pins. 
     One method of effectuating a repair is shown in  FIGS. 4-7 .  FIG. 4  shows ends  2  and  4  of ruptured tendon  1  being initially attached with a suture.  FIG. 5  shows a needle  14  with end  12 A of implant  11  attached thereto being pushed through first end  2  of tendon  1 . This pulls part of the body portion  12  into the first end  2 . When the needle  14  passes through the outer surface of tendon  1  it pulls the implant  11  with it. The implant material is cut away from the needle  14 , and preferably close to the outer surface of the tendon  1 . 
     This same procedure is repeated on end  4  of tendon  1 . 
     Once the implant  11  is positioned in tendon  1 , the ruptured ends on the tendon and the implant are mechanically attached. As shown in  FIG. 7 , this is done using any of the known tendon suturing techniques. Any suitable technique, however, such as a suturing technique, stapling, or other mechanical method of attachment could be utilized. Adhesive might be used to augment the repair. In this manner, the implant adds significant strength to the rupture area and helps to prevent it from rupturing or pulling apart partially to create a gap under a load prior to healing. 
     An alternate implant  30  is shown in  FIGS. 16 and 17 . Implant  30  is a hollow tube into which the first end  2  and second end  4  of the ruptured tendon  1  are placed so they touch, and are preferably pressed together. In this embodiment, there is an opening  31  along one side of insert  30  to make placement of insert  30  around tendon  1  simple. The implant  30  has an inner surface  32  defining a cavity  34  that is dimensioned to receive each end  2  and  4  of ruptured tendon  1 . The tendon ends  2  and  4 , and the implant  30  would then be mechanically attached with any of the prior mentioned suture techniques, staples, rivets, pins, clamps, or in any suitable manner. Additionally, inner surface  32  may include apparatus  36  that enables each end  2  and  4  of tendon  4  to be inserted into cavity  34 , and that tend to hold the ends of the tendon in place and resist the ends  2  and  4  from being removed from cavity  34 . 
     For example, inner surface  32  could have structures  36  that are backward-facing ribs or barbs as shown in  FIG. 17A , which could extend any suitable distance outward from inner surface  32 . Such structures could, for example, extend between 0.5 mm to 2 mm from inner surface  32 . 
     Once the ends  2  and  4  of tendon  1  have been inserted into implant  30 , the ends and implant  30  are mechanically attached in the manner previously described with respect to implant  11 . 
     Alternatively, an implant placed on the outside of tendon  1  may not have any openings, such as opening  31 , as shown in cross-sectional view  30 A. 
       FIG. 9  shows needles  40  that can be used to secure a tendon in place with ends  2  and  4  juxtaposed prior to or after an insert  11  or insert  30  has been placed in or on the tendon  1  and secured thereto. 
       FIG. 10  depicts staples or rivets  45  that are placed by a stapler  42  to secure a tendon and insert inside of or outside the tendon according to methods and structures of the invention. 
       FIG. 11  shows rivets  45  positioned through an outer insert  30  and through a tendon  1  to hold insert  30  and ruptured ends  2  and  4  in place. 
       FIG. 12  shows another type of rivet  46  that can be used to secure a ruptured tendon and insert in position. 
       FIG. 13  shows a method and structure by which a ruptured tendon  1  is secured on spikes  50  to hold it in place. As shown in this Figure, a knife or needle is pushed through tendon  1  to pull insert  11  therethrough to strengthen the rupture area at ends  2  and  4 . The tendon  1  and insert  11  are then mechanically secured using any of the techniques described herein. However, pins or spikes may be used to secure a tendon in place prior to repair using several of the techniques described herein. 
       FIGS. 14 and 15 , which have previously been described, show alternate embodiments of insert  11  that is positioned inside of tendon  1  to effectuate a rupture repair. 
       FIGS. 18-20  show alternate configurations of insert  11  that may be positioned inside of tendon  1  to effectuate a rupture repair. Any of these embodiments may include structures such as stiplets, ribs, barbs or textured surfaces to secure them inside of a tendon  1 . 
       FIGS. 21-22  show a clamp  60  according to the invention and a tool  70  that may be used to position and compress clamp  60 . Clamp  60  and tool  70  are known to those skilled in the art. 
     Having thus described some embodiments of the invention, other variations and embodiments that do not depart from the spirit of the invention will become apparent to those skilled in the art. The scope of the present invention is thus not limited to any particular embodiment, but is instead set forth in the appended claims and the legal equivalents thereof. Unless expressly stated in the written description or claims, the steps of any method recited in the claims may be performed in any order capable of yielding the desired result.