Patent Publication Number: US-11020162-B2

Title: Bending pin

Description:
PRIORITY CLAIM 
     The present application is a Continuation Application of U.S. patent application Ser. No. 14/581,836 filed on Dec. 23, 2014, now U.S. Pat. No. 9,968,393. The disclosure of the above patent(s)/application(s) is incorporated herein by reference. 
    
    
     BACKGROUND 
     Implants such as, for example, bone plates, must often be contoured to a fit a patient&#39;s specific anatomy to properly fix a fracture. The bone plates may be bent by a surgeon or other user using bending pins slid over drill guides that are pre-assembled with the bone fixation element receiving holes of the bone plate. Forces applied to the bending pins are transferred to the drill guides attached to the bone plate until the bone plate is bent, as desired. This process, however, exerts bending forces directly to the threading formed in bone fixation element receiving holes and, in some cases, may damage the bone plate beyond usability. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a system for bending an implant, comprising a drill guide extending longitudinally from a proximal end to a distal end, the drill guide including a distal portion having a first threading extending therealong to engage a threading along an interior of a bone fixation element receiving hole of an implant and a proximal portion having a second threading extending therealong and a bending pin extending longitudinally from a proximal end to a distal end including a recess extending proximally therefrom, the recess sized and shaped to receive the proximal portion of the drill guide and including a corresponding threading therealong for engaging the second threading. 
    
    
     
       BRIEF DESCRIPTION 
         FIG. 1  shows longitudinal side view of a system according to an exemplary embodiment of the present invention; 
         FIG. 2  shows a side view of a drill guide according to the system of  FIG. 1 ; 
         FIG. 3  shows a longitudinal cross-sectional view of the drill guide of  FIG. 2 ; 
         FIG. 4  shows a side view of a bending pin according to the system of  FIG. 1 ; and 
         FIG. 5  shows a partial longitudinal cross-sectional view of the bending pin of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention may be further understood with referenced to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present invention is directed to a system for treating a bone and, in particular, to a system for bending an implant to correspond to a patient&#39;s anatomy. Exemplary embodiments of the present invention describe a system comprising a drill guide engaged within a bone fixation element receiving hole of an implant and a bending pin threadedly engagable with the drill guide to contact a surface of the implant so that bending forces applied to the bending pin are directly applied to the implant. It will be understood by those of skill in the art that the terms “proximal” and “distal” refer to a direction toward (proximal) and away from (distal) a user of the device. 
     As shown in  FIGS. 1-5 , a system  100  according to an exemplary embodiment of the present invention comprises a plurality of drill guides  102 , each of which engages a bone fixation element receiving hole  104  of an implant such as, for example, a bone plate  106 . The system  100  further comprises a plurality of bending pins  108 , each bending pin  108  engagable with a corresponding one of the drill guides  102  so that a distal end  110  of the bending pin contacts the bone plate  106 . Thus, when the bending pins  108  are moved relative to one another to bend the bone plate  106 , the bending force is applied directly to a proximal surface  144  of the bone plate  106  (i.e., a surface which, when the plate  106  is mounted on a target portion of bone, faces away from the bone). Applying the bending forces to the proximal surface  144  of the plate  106  prevents damage to the bone fixation element receiving holes  104  of the bone plate  106 . In contrast, conventional bending pins are slid over the drill guides, which are pre-assembled with the bone plate. Conventional bending pins and drill guides do not include any features that mate with one another so that, when bending forces are applied, one side of the bending pin will rise off of the plate, out of contact therewith, causing forces to be applied directly to the threads of the drill guide and the bone fixation element receiving holes of the bone plate with which the drill guides are engaged. This may cause the drill guides to back out of the bone fixation element receiving holes and/or cause extensive damage to the bone fixation element receiving holes of the bone plate. It will be understood by those of skill in the art, that the engagement of the bending pin  108  and the drill guide  102  of the present invention prevents damage to the threading of the bone fixation element receiving holes  104  of the bone plate  106  being bent thereby. 
     As shown in  FIGS. 2 and 3 , each drill guide  102  extends longitudinally from a proximal end  112  to a distal end  114  and includes a channel  116  extending longitudinally therethrough to accommodate, for example, a drill bit for drilling a hole into a bone along an axis of the channel  116 . The drill guide  102  include a distal portion  118  extending proximally from the distal end  114  for engaging a bone fixation element receiving hole  104  of the bone plate  106  and a proximal portion  120  extending distally from the proximal end  112  for engaging a corresponding one of the bending pins  108 . The distal portion  118  includes a first threading  122  extending therealong for engaging a threading of the bone fixation element receiving hole  104 . The proximal portion  120  includes a second threading  124  extending therealong for engaging a corresponding threading  126  of the bending pin  108 . Extending between the distal portion  118  and the proximal portion  120 , the drill guide  102  includes a non-threaded portion  128  that acts as a shoulder for directing force between the bending pin  108  and the drill guide  102 . The first and second threadings  122 ,  124  may have different pitches. 
     In one exemplary embodiment, the distal portion  118  tapers from a proximal end  130  thereof toward the distal end  114  to engage a tapered bone fixation element receiving hole  104  (e.g., a locking screw hole). The proximal portion  120  may have a substantially constant cross-sectional area along a length thereof. The proximal portion  120  may also include a flat surface  146  extending along a length thereof. In an exemplary embodiment, the proximal portion  120  includes a pair of flat surfaces  146  diametrically opposed from one another. The flat surfaces  146  may engage a tool which is used to assemble the drill guide  102  with the bone plate  106  so that assembling the drill guide  102  to the bone plate  106  does not cause any damage to the second threading  124  of the drill guide  102  and/or any portion of the bending pin  108 , which may otherwise be used to assemble the drill guide  102  to the bone plate  106 . 
     As shown in  FIGS. 4 and 5 , each of the bending pins  108  extends longitudinally from a proximal end  132  to the distal end  110 . The bending pin  108  includes a drill guide engaging portion  136  extending proximally from the distal end  110  and a gripping portion  138  at the proximal end  132  thereof. The gripping portion  138  according to this embodiment includes knurls  148  extending therealong and thereabout to facilitate a gripping thereof by a user. The drill guide engaging portion  136  includes a recess  140  at the distal end  110  sized and shaped to receive the proximal portion  120  of the drill guide  102 . The recess  140  includes the threading  126  extending along a portion thereof for engaging the second threading  124  and a non-threaded portion  142  along a distal portion thereof for receiving the non-threaded portion  128  of the drill guide  102 . The drill guide engaging portion  136  according to this embodiment also includes a pin  134  extending longitudinally within the recess  140  along a central axis thereof, as shown in  FIG. 1 . The pin  134 , however, is not a required feature as the engagement between the proximal portion  120  of the drill guide  102  and the drill guide engaging portion  136  of the bending pin  108  is sufficient to transfer the bending force from the bending pin  108  to the proximal surface  144  of the drill guide  102 . Each of the bending pins  108  may also include a through-hole  150  extending laterally through the drill engaging portion  136  so that the through-hole  150  is in communication with the recess  140 . The through-hole  150  may be used to clean the recess  140 , including the threading  126  and the non-threaded portion  142 . 
     In use, the drill guides  102  may be pre-assembled with the bone plate  106  with the distal portion  118  of each of the drill guides  102  received within a corresponding one of the bone fixation element receiving holes  104  of the bone plate  106 . In particular, the first threading  122  of the distal portion  118  is threadedly engaged with the bone fixation element receiving hole  104  so that the proximal portion  120  and the non-threaded portion  128  extend proximally from the proximal surface  144  of the bone plate  106 . Each of the bending pins  108  is then engaged with a corresponding one of the drill guides  102 . Specifically, the proximal portion  120  is received within the recess  140  of the bending pin  108 , the bending pin  108  being rotated about a longitudinal axis thereof so that the threading  126  along the interior of the recess  140  engages the second threading  124 , The bending pin  108  is rotated relative to the drill guide  102  until the distal end  110  contacts the proximal surface  144  of the bone plate  106  and the non-threaded portion  128  of the drill guide  102  is received within the non-threaded portion  142  at the distal end of the recess  140 . 
     Once a desired number of bending pins  108  has been engaged with the drill guides  102 , a user grips the gripping portions  138  of first and second ones of the bending pins  108 , moving the first and second bending pins  108  relative to one another to bend the bone plate  106  as desired. As would be understood by those skilled in the art, different bending pins  108  may be moved relative to one another in selected directions to bend the bone plate  106  as desired. The non-threaded portion  128  of the drill guide  102  within the non-threaded portion  142  of the bending pin  108  acts as a guide to direct the bending force applied to the bending pin  108  to the drill guide  102 . As described above, the contact between the bone plate  106  and the distal end  110  of the bending pin  108  applies the bending force directly to the proximal surface  144  of the bone plate  106 , preventing damage to the bone fixation element receiving holes  104 . 
     It will be apparent to those skilled in the art that variations can be made to the structure and methodology of the present invention, without departing from the scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of the appended claims and their equivalents.