Abstract:
An angled driver assembly including a rotatable shaft rotatable about a first axis, a rotatable cutting device rotatable about a second axis, the first rotatable portion being coupled to the second rotatable portion, a reference device associated with the rotatable cutting device and an indicator linked to the reference device. The indicator indicates a position of the rotatable cutting device relative to the reference device.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an orthopeadic driver, and, more particularly, to an offset orthopeadic driven cutting device.  
         [0003]     2. Description of the Related Art  
         [0004]     An orthopeadic cutter is used to cut a hole in a bone. The cutter may be a drill or a reamer used to cut a bone to a predetermined shape for receiving an orthopeadic implant. For example, an intramedullary reamer may be placed into the intramedullary canal of the bone and used to ream the interior of a bone to receive a stem of an orthopeadic implant. Such a reamer includes a radial peripheral surface which generally includes a plurality of radially extending teeth for cutting the bone in a radial direction as the reamer proceeds in an axial direction in the bone. The size of the opening formed in the bone is determined by the outside diameter of the reamer.  
         [0005]     Orthopeadic drills are used to form openings in bones for the receiving of implant devices such as a pin. Drills are rotating devices with a cutting edge for the removal of a portion of the bone.  
         [0006]     What is needed in the art is an orthopeadic drill which effectively removes bone to a desired depth.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides an orthopeadic drill driver including an offset driving shaft and an indicator that indicates the depth that a drill extends into a bone.  
         [0008]     The invention comprises, in one form thereof, an angled driver assembly including a rotatable shaft rotatable about a first axis, a rotatable cutting device rotatable about a second axis, the first rotatable portion being coupled to the second rotatable portion, a reference device associated with the rotatable cutting device and an indicator linked to the reference device. The indicator indicates a position of the rotatable cutting device relative to the reference device.  
         [0009]     An advantage of the present invention is that the surgeon using the device knows the depth that the drill extends into the bone as the drilling operation is underway.  
         [0010]     Another advantage of the present invention is that the depth of a blind hole, offset from the observer, is shown on a gauge as bone is being removed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:  
         [0012]      FIG. 1  is a perspective view of an embodiment of an orthopeadic angled driver of the present invention;  
         [0013]      FIG. 2  is another perspective view of the orthopeadic driver of  FIG. 1 ; and  
         [0014]      FIG. 3  is yet another perspective view of the orthopeadic driver of  FIGS. 1 and 2  showing the cutter in the extended position. 
     
    
       [0015]     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0016]     Referring now to the drawings, and more particularly to  FIGS. 1-3 , there is shown an embodiment of an orthopeadic driver  10  of the present invention, which is used for drilling or reaming bone. Orthopeadic driver  10  includes a rotating driver  12 , a cutter  14 , a spring  16 , a reference device  18 , a handle  20 , a gauge  22 , a linkage  24 , an indicator  26 , a motion translator  28  and a tube  30 .  
         [0017]     Rotating driver  12 , also known as a rotating shaft  12  rotates about an axis L. One end of rotating shaft  12  is connected to motion translator  28  and another end of rotating shaft  12  is connected to a power device, not shown, for the rotation of rotatable shaft  12 . Rotatable shaft  12  transfers motion along its length to motion translator  28 . Bearing surfaces within tube  30  may hold rotatable shaft  12  in position relative to tube  30 .  
         [0018]     Cutter  14  is a rotating cutter, which may be in the form of a drill bit  14 , which is connected at one end of motion translator  28 . Cutter  14  has cutting edges for the removal of bone when extended beyond reference device  18 . Cutter  14  may be in the form of a reamer  14 , which is rotatable about an axis M. Axis M is offset from axis L and is, preferably, substantially perpendicular to axis L. Spring  16  biases reference device  18  so that cutter  14  does not extend through reference device  18  until reference device  18  is seated against a portion of bone and the bias of spring  16  is overcome. Reference device  18  has an opening through which cutter  14  extends and is positioned relative to an end of cutter  14  so that when cutter  14  extends a distance A from reference device  18  then its position is indicated by the relative position of indicator  26  to gauge  22 . Linkage  24  is connected to reference device  18 . Linkage  24  has an extended slot which interacts with a portion of either tube  30  or motion translator  28  to keep reference device  18  axially aligned with cutter  14  as reference device  18  translates along a portion of the length of cutter  14 .  
         [0019]     Gauge  22  is connected to an end of tube  30  having indicia thereon for indicating the drilling depth of cutter  14  relative to reference device  18 . The indicia on gauge  22  may be numeric, color coded or the like to indicate the measured depth of cutter  14 . A handle  20  may be connected to a portion of gauge  22  to control the positioning of driver  10  as it is positioned relative to a bone that is to be drilled.  
         [0020]     Indicator  26  is shown as a rod-like device attached at one end to linkage  24 . Another end of indicator  26  floats in gauge  22  so that the end of indicator  26 , proximate to gauge  22 , indicates the relative position of linkage  24 , which is connected to reference  18 , which as a result of its relationship with cutter  14  indicates the depth of cutter  14  as it drills beyond reference device  18 .  
         [0021]     Motion translator  28  translates the motion of shaft  12 , as it rotates about axis L to cutter  14  as it rotates about axis M. Motion translator  28  may include a cog-type arrangement, a beveled-geared arrangement, a worm gear assembly, a flexible shaft or any other known method of translating rotary motion about one axis to rotary motion about another axis. Motion translator  28  has a stationary portion connected to tube  30  and a rotating portion connected to rotatable shaft  12 . Motion translator  28  has a second rotating portion connected to cutter  14 , thereby transferring motion about axis L to motion about axis M.  
         [0022]     As can be seen in  FIG. 3 , cutter  14  is extended a distance A from reference device  18 , which is translated to a movement of indicator  26  by a distance A relative to gauge  22 . The movement of cutter  14  corresponds to the movement of indicator  26 , thereby showing a surgeon the depth that cutter  14  has extended into the bone. The correspondence between the movement of indicator  26  and the movement of cutter  14  may be a one-to-one relationship as illustrated in  FIG. 3 . As driver  10  is positioned proximate to the bone, reference device  18  encounters a surface of the bone. As shaft  12  is rotated and longitudinal pressure is applied by way of handle  20  causing cutter  14  to advance and overcome the bias of spring  16 , cutter  14  extends through an opening in reference device  18  to begin the cutting operation. When the desired depth is reached, as indicated by the relative position of indicator  26  with gauge  22 , the surgeon knows that the desired depth has been reached and pressure is removed as cutting device  14  is retracted back through the opening in reference device  18  and driver  10  is removed from an incision in the patient.  
         [0023]     While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.