Patent Publication Number: US-2019192279-A1

Title: Apparatus and Method for Clamping and Trimming the Bone Tendon Portion of a Graft to a Desired Size

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. utility application Ser. No. 15/862,018, filed Jan. 4, 2018, which is a continuation of U.S. utility application Ser. No. 14/825,626, filed Aug. 13, 2015, now U.S. Pat. No. 9,872,761, issued Jan. 23, 2019, which claims the benefit of provisional application No. 62/036,942, filed Aug. 13, 2014, the disclosures of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to instruments used during surgical procedures for securing a bone tendon bone graft inside bone tunnel. More particularly, this invention relates to bone clamping instruments for trimming the bone tendon portion of a graft for a replacement anterior cruciate ligament (ACL) or other tendon/ligament. 
     Description of the Background Art 
     Presently there exist many surgical techniques employed for replacing, reconstructing or securing synthetic or biological connective tissues to bone surfaces, such as attaching and maintaining an anterior cruciate ligament (ACL) within a knee. More recent surgical procedures for tendon replacement and reconstruction involve auto-grafting a tendon to the site of a torn or dislocated tendon. Early surgical procedures involved stapling the auto-grafted tendon into placement. 
     More particularly, reconstruction is the standard of care after an ACL injury. In surgery it is generally known to use an autograft taken from the knee of the patient to replace the ruptured ACL. The two most commonly used are the bone-patellar tendon bone (BPTB) and the hamstring tendon (semitendinosus tendon with or without gracilis tendon). Allografts, synthetic grafts and quadriceps tendon grafts have also been used as ACL substitutes. The surgical techniques of the ACL reconstruction using bone-tendon bone (BTB) graft and hamstring tendon graft are described in detail in the following references: Beck, C. L., Jr.; Paulos, L. E.; Rosenberg, T. D.: “Anterior cruciate ligament reconstruction with the endoscopic technique,”  Operative Techniques in Orthopaedics,  2:96-98, 1992; Stahelin, A. C.; Weiler, A.: “All-inside anterior cruciate ligament reconstruction using semitendinosus tendon and soft threaded biodegradable interference screw fixation,”  Arthroscopy,  13:773-779, 1997; Fu, F. H.; Ma, C. B.: “Anterior Cruciate Ligament Reconstruction Using Quadruple Hamstring. Operative Techniques,”  Orthopaedics,  9:264-272, 1999. Additional references of interest include Hoffman, R. F. G.; Peine, R; Bail, H. J.; Sudkamp, N. P.; Weiler, A.: “Initial fixation strength of modified patellar tendon grafts for anatomic fixation in anterior cruciate ligament reconstruction,”  Arthroscopy,  15:392-399, 1999. The disclosures of each of the above references are hereby incorporated by reference herein. 
     More specifically, among the currently available soft tissue (hamstring) graft fixation implants, currently the most commonly used method to secure an ACL substitute to a bony drill-hole in an ACL reconstruction, is the interference technique. In the interference technique, an interference screw is inserted into the space between the drill-hole and the bone tendon portion of the graft to lock it into the drill-hole. The fixation screws, like interference screws, are normally made of metal, like stainless steel or titanium or of a bioabsorbable polymer, like polylactide. 
     For example, as taught by U.S. Pat. No. 5,397,356, one technique for securing a replacement tendon to a bone involves harvesting a tendon having a bony section or plug at one or both ends. The tendon is threaded into a drilled hole by a guide pin or K-wire and then the bone plug is secured into position by a specially-adapted threaded pin. Importantly, the threaded pin securing the replacement tendon engages through its bony plug to secure it into position within the hole whereupon, over time, the bony plug is grafted into the knee, thereby permanently securing the replacement tendon into position. 
     It is important to trim the bone tendon portion of the graft to properly fit inside the bony drill-hole. Unfortunately, prior art techniques have involved trimming the bone tendon portion with a bone saw by hand without the aid of an instrument and possibly resulting in incorrect sizing of the bone tendon portion either too large or too small to properly fit into the boney drill hole. 
     An object of this invention is to provide a bone clamping instrument for clamping the bone tendon portion of the graft during an ACL procedure allowing the surgeon to properly trim the bone tendon portion of the graft with a bone saw to precise dimensions to properly fit into the hole. 
     The foregoing has outlined some of the pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings. 
     SUMMARY OF THE INVENTION 
     For the purpose of summarizing this invention, this invention comprises a bone clamping instrument for clamping the bone tendon portion of the graft during an ACL procedure allowing the surgeon to properly trim the bone tendon portion of the graft with a bone saw to precise dimensions to properly fit into the hole. The instrument of the invention comprises a pair of jaws pivotally connected together in the form of a scissor arrangement with handles. The jaws, when closed, define a generally U-shaped trapezoidal receptacle to grasp the bone tendon portion of the graft. As the bone tendon portion is cradled between the jaws, the upper surfaces of the jaws provide a level bone-cutting surface allowing the surgeon, with the aid of a conventional bone saw, to trim off any portion of the bone tendon portion protruding from the top of the U-shaped trapezoidal receptacle. Once trimmed, the bone tendon will have a height equal to the depth of the U-shaped trapezoidal receptacle, thereby assuring that the bone tendon portion will be trimmed to properly fit into the boney hole. 
     The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which: 
         FIGS. 1A, 1B, 1C and 1D  are perspective, top plan, right plan and front plan views, respectively, of the bone clamping instrument of the invention illustrating the generally U-shaped trapezoidal receptacle formed by the jaws of the instrument when closed; 
         FIGS. 2A and 2B  are enlarged, partial perspective views of the generally U-shaped trapezoidal receptacle formed by the jaws of the instrument when closed; 
         FIG. 3A  is a perspective view of the bone clamping instrument of the invention illustrating the generally U-shaped trapezoidal receptacle formed by the jaws of the instrument when partially opened; 
         FIGS. 3B and 3C  are perspective views of the disassembled right and left handles, respectively, of the instrument showing the cut-outs formed along the bottom of the respective jaws to define a through-slot into which the drill bit may pass when drilling a hole into the bone tendon portion. 
         FIGS. 4-56  are photographs of a surgical ACL procedure utilizing the bone clamping instrument of the invention. 
     
    
    
     Similar reference characters refer to similar parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1A-1D , the bone clamp  10  of the invention comprises a pair of elongated handles  12  and  14  each having thumb/finger loops  16  and  18  at one end and jaws  24  and  26  at their other end. The handles  12  and  14  are hinged together at pivot point  22  allowing the jaws  24  and  26  to open and close in a scissor arrangement. The jaws  24  and  26  define a generally U-shaped trapezoidal receptacle  31  when the jaws  24  and  26  are closed (see  FIG. 1C ) to grasp the bone tendon portion of the graft to be trimmed. The jaws  24  and  26  comprise respective upper guide surfaces  28  and  30  along their upper edge. When a bone tendon portion is positioned in the trapezoidal receptacle  31 , the upper guide surfaces  28  and  30  function as a guide for the blade of the bone saw to trim the excess portion of the bone tendon portion protruding above the upper surfaces  28  and  39 . 
     A conventional clamp mechanism  20  releasably interconnects the handles  12  and  14 . The clamp mechanism  20  comprises respective fingers  20 F emanating from the handles  12  and  14 , preferably at their loops  16  and  18 . Each finger  20 F comprises ratchet teeth  20 T to engage the mating ratchet teeth  20 T of the other finger  20 F in a mating, progressively locking manner to progressively lock the jaws  24  and  26  as the jaws  24  and  26  are moved closed. The jaws  24  and  26  may then subsequently opened by twisting the handles  12  and  14  apart to disengage the ratchet teeth  20 T. 
     As best shown in  FIG. 3A , preferably the fingers  20 F are dimensioned such that their respective outermost ratchet teeth  20 T start to engage one another when the jaws  24  and  26  are about to close. Then, as the scissor arrangement fully closes, additional respective ratchet teeth  20 T engage (compare the partially-closed  FIG. 3A  with the fully-closed  FIG. 1A ). 
     Referring to  FIGS. 2A and 2B , the jaws  24  and  26  are configured as mirror images of one another (see also  FIGS. 3B and 3C ), having respective upstanding, inwardly-sloping sidewalls  32  and  34  (i.e., sloping from a narrower width at the top to a wider width at the bottom of the jaws  24  and  26  to define the generally U-shaped trapezoidal receptacle  31  when the jaws  24  and  26  are closed (see  FIG. 1C ) to grasp the bone tendon portion of the graft to be trimmed. The jaws  24  and  26  comprise respective upper bone saw upper guide surfaces  28  and  30  along their upper edges. 
     During use with the bone tendon portion of the graft cradled in the jaws  24  and  26  and the clamping mechanism  20  clamped together to hold the bone tendon portion therebetween, the surgeon may trim any excess of the bone tendon portion protruding above the upper guide surfaces  28  and  30  using a conventional bone saw by simply resting and moving the bone saw blade along the upper guide surfaces  28  and  30 , thereby assuring that the bone tendon portion will have a fixed height equal to the depth of the U-shaped trapezoidal receptacle. 
     The process may then be repeated to trim along other side(s) of the bone tendon portion, by releasing the bone tendon portion from the jaws  24  and  26 , rotating it to the side to be trimmed (e.g., ninety degrees), re-grasping it with the jaws  24  and  26  and then trimming the protruding excess of the bone tendon portion. 
     More particularly, as best shown in  FIG. 1C , the transverse cross-sectional configuration of the generally U-shaped trapezoidal receptacle  31  is defined by the inwardly-sloping sidewalls  32  and  34  which function to securely grasp the bone tendon portion when clamped between the jaws  24  and  26 . As best shown in  FIG. 2A, 3B and 3C , the length of the longitudinal cross-sectional configuration of the generally U-shaped trapezoidal receptacle  31  is defined by the length of the respective upstanding rear walls  40  and  42 . The rear walls  40  and  42  are preferably arcuate shaped to define a generally rounded rear of the generally U-shaped trapezoidal receptacle  31 . 
     As best shown in  FIGS. 3B and 3C , the pivot point  22  comprises upper and lower generally flat leafs  22 L that mate together and are secured in a pivoting arrangement by a pivot screw  22 S engaged through a hole  22 H formed in one leaf  22 L into the threaded hole  22 T of the other leaf  22 L thereby forming a single-point pivot  22 . The rear portions of the leafs  22 L are connected to the front ends of the respective handles  10  and  12  whereas the front portions of the leafs  22 L are connected to the rear portions of the respective jaws  24  and  26 . 
     Referring now to  FIGS. 3B and 3C  showing the disassembled right and left handles  10  and  12 , a cut-out  36 C is formed along the mating sides of the respective bottoms  36  and  38  of the jaws  28  and  30 . As shown in  FIG. 1B , when the jaws  28  and  30  are closed, the mating cut-outs  36 C define a through-slot  36 S. The through-slot  36 S allows space for the tip of the drill bit to pass into when drilling a hole into the bone tendon portion. 
     The bone clamp  10  of the invention may be used in a variety of surgical procedures for trimming a bone tendon portion of a graft. One particular procedure in which the bone clamp  10  has been found to be particularly useful is for ACL repairs.  FIGS. 4-56  illustrate such a procedure. 
       FIG. 4  shows the inferior pole of the patella tendon harvested from its insertion into the tibial tubercle. 
       FIGS. 5 through 11  show the bone clamp  10  of the invention grasping the bone tendon portion of the graft and securing it into place. Note that the clamp  10  is shaped like a trapezoid to cradle the bone graft which is harvested also in the shape of a trapezoid. 
       FIG. 8  shows the graft in the middle of the bone clamp secured into place. The clamp  10  provides a convenient cutting surface by virtue of the level, upper surfaces  28  and  30  of the upstanding walls  32  and  34 . This cutting surface will support the saw blade as it makes a smooth straight cut along the top portion of the bone plug. It is the measured (e.g., 10 mm) cutting surface of the upper surfaces  28  and  30  for the bone plug and the security of the graft in the clamp that provides the new advantage of using this clamp  10  in surgery. 
       FIG. 12  shows the saw blade being used against the upper surfaces  28  and  30  of the clamp  10  to cut a precise (e.g., 10 mm) bone plug that is attached to the patella tendon. This provides a uniform graft fit within the bone tunnel that leads to the reconstruction of the ACL. 
       FIGS. 12 through 25  show the saw blade being used against the upper surfaces  28  and  30  of the clamp  10  to obtain a very precise bone plug. 
       FIGS. 26 and 27  show a second pass of the saw blade over the bone plug to make sure that there are no rough edges that may possibly get caught up in the boney hole/tunnel. 
       FIGS. 28 through 31  show the bone plug after it is contoured in the grasp of the clamp  10 . 
       FIGS. 32 through 36  show the bone plug being drilled with a drill bit to make holes to receive the large number five tycron sutures. 
       FIG. 37  shows the sutures are being placed through the graft so that the graft can be secured into the knee joint. The graft on the patella side is secured with a button. The graft on the tibial side is secured with a screw and washer. The sutures loop around the screw and washer to help hold the graft in place. 
       FIG. 38  shows the inferior portion of the graft secure with sutures. 
       FIGS. 39 through 53  show the technique being repeated on the patella portion of the graft. The patella portion of the bone is shorter but has the same thickness (e.g., 10 mm). Despite the difference in length, the clamp  10  may be used on either lengths of the bone plugs due to the longer-than-needed length of the generally U-shaped trapezoidal receptacle defined by respective upstanding rear walls  40  and  42 . 
       FIGS. 55 and 56  show a drill hole made into the patella portion of the graft and with sutures passed through the patella portion of the graft just as they were passed through on the tibial portion of the graft. Now the graft is prepared to be passed into the knee joint and the patella tendon is turned into the ACL. 
     The present disclosure includes that contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention. 
     Now that the invention has been described,