Abstract:
A surgical instrument handle operates a microsurgical instrument on a surgical instrument head by manipulation of the instrument handle. The instrument handle has an elongate center rod with a ring mounted on the rod for reciprocating movement. The ring is operatively associated with the surgical instrument head for operation of the microsurgical instrument of the head. A plurality of resilient arms extend along the length of the rod and engage against a sliding surface of the ring. The inward and outward movement of the plurality of arms reciprocates the ring on the handle rod to cause operation of the surgical instrument head.

Description:
[0001]    This patent application is a continuation application of U.S. patent application Ser. No. 10/586,018, which was filed on Nov. 15, 2004, and is currently pending. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
       [0002]    Features of the invention are set forth in the following detailed description of the preferred embodiment of the invention and in the following drawing figures wherein: 
         [0003]      FIG. 1  is a cross section of the instrument handle of the invention; and, 
         [0004]      FIG. 2  is a view of the disassembled component parts of the instrument handle of the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0005]    The surgical instrument handle of the invention is employed with microsurgical instrument heads of the type disclosed in the U.S. Pat. of Scheller et al. No. 5,370,658, and the U.S. Pat. of Gampp, Jr. et al. No. 5,893,877, both of which are incorporated herein by reference. The surgical instrument heads disclosed in these patents have surgical instruments at their distal ends that are actuated in response to reciprocating movement of head pistons at their proximal ends. The instrument handle of the invention is designed to be attached to surgical instrument heads of the type disclosed in the above referenced patents to actuate the surgical instruments of the instrument heads. 
         [0006]    The instrument handle of the invention is manually actuated in a manner to be described, to move a piston on the instrument handle that in turn moves the head piston of the surgical instrument head attached to the handle. In this way, the instrument handle of the invention actuates the surgical instrument head of the type described in the above referenced patents. In operation of the instrument handle of the invention, the handle piston is moved against a spring-biased piston of the instrument head to produce a first stage of movement in the surgical instrument at the distal end of the instrument head. The bias on the instrument head piston against the piston of the instrument handle causes the surgical instrument at the instrument head distal end to move from its first stage of movement to its second stage of movement. 
         [0007]    The surgical instrument handle of the invention is basically comprised of an interior assembly and an exterior assembly. The interior assembly includes a cylindrical base  12 , an elongate rod  14 , a piston  16 , a ring  18 , a piston stop  22 , and a rear cap  24 . 
         [0008]    The cylindrical base  12  has a center axis with opposite proximal  26  and distal  28  ends. External screw threading  32  is provided on the exterior of the base adjacent the base proximal end  26 . A center bore  34  extends through the base. A pinhole  36  extends transversely through the base and intersects the center bore  34 . Internal screw threading  37  is provided in the center bore  34  adjacent the base proximal end  26 . 
         [0009]    The elongate rod  14  has a center axis and opposite proximal  38  and distal  42  ends. A pinhole  44  extends transversely through the rod proximal end  38 . A surgical instrument head connector  46  having external screw threading is provided at the rod distal end  42 . The instrument connector  46  has an axial center bore  48 . A piston slot  52  extends transversely through the rod  14  and extends axially along the rod for a short distance adjacent the instrument connector  46 . The slot  52  intersects the instrument connector center bore  48 . 
         [0010]    The piston  16  is received in the rod slot  52  for reciprocating axial movement of the piston through the rod slot. The piston  16  has a pair of transversely extending shoulders  54  intermediate the opposite proximal  56  and distal  58  ends of the piston. The piston distal end  58  projects from the pair of shoulders  54  through the center bore  48  of the rod instrument connector  46 . 
         [0011]    The ring  18  is mounted on the rod  14  for axial sliding movement of the ring. The ring has an annular cavity  62  recessed into a distal end face  64  of the ring. The annular cavity  62  receives the piston shoulders  54  to operatively connect the piston  16  with the ring  18 . A proximal end face  66  of the ring  18  is formed as a conical sliding surface. 
         [0012]    The piston stop  22  is cylindrical and has a center bore  68  that receives the elongate rod  14 . The piston stop  22  is positioned adjacent the slot  52  in the rod distal end. A set screw  72  is received in an internally threaded hole  74  in the side of the piston stop  22  and engages with the elongate rod  14  to secure the piston stop in a desired position on the rod. The position of the piston stop  22  on the rod  14  limits the movement of the piston  16  toward the rod proximal end  38 . 
         [0013]    The rear cap  24  is provided with an externally threaded shank  76  and a cylindrical head  78 . The screw threads on the rear cap shank  76  are screwed into the internal screw threading  37  at the base proximal end  26  closing the hollow interior of the base at its proximal end. 
         [0014]    The exterior assembly of the surgical instrument handle is comprised of a tubular forward grip member  82 , a tubular rearward grip member  84 , and a pin  86 . The forward grip member  82  has a center bore  87  with a center axis extending through the length of the grip member. The bore  87  extends from a proximal end  88  to a distal end  92  of the grip member. A pair of diametrically opposed elongate slots  94  are formed transversely through the forward grip member  82  adjacent the proximal end  88 . The slots  94  extend axially along a portion of the length of the forward grip member adjacent the proximal end  88 . A portion of the forward grip member interior bore surface  96  tapers radially outwardly as it extends from the interior bore to the forward grip member distal end  92 . A plurality of axially extending slots  98  are formed in the forward grip member  82  at the forward grip member distal end  92 . The axial slots  98  extend along the length of the forward grip member  82  from the distal end  92 , but end short of the forward grip member proximal end  88 . The axial slots  98  form a plurality of resilient arms  102  that are circumferentially arranged around the interior bore  87  of the forward grip member. 
         [0015]    The rearward grip member  84  is a cylindrical tube having opposite proximal  104  and distal  106  ends. The exterior surface of the rearward grip member  84  is smooth. Internal screw threading  108  is provided inside the rearward grip member  84  adjacent the distal end  106 . The internal screw threading  108  is complementary to the external screw threading  32  of the base  12 . 
         [0016]    The surgical instrument handle is assembled by first positioning the piston  16  in the slot  52  at the rod distal end  42 . The ring  18  is then positioned over the rod and the piston shoulders  54  are received in the ring annular cavity  62 . The piston stop  22  is then positioned over the rod adjacent the slot  52 . The piston stop  22  is secured in its desired position adjacent the slot  52  by tightening the set screw  72  in the set screw hole  74  of the stop. The elongate rod proximal end  38  is then inserted into the base center bore  34  at the base distal end  28 . The pinhole  44  of the rod is aligned with the pinhole  36  of the base. 
         [0017]    The exterior assembly of the instrument handle is then assembled onto the interior assembly. The forward grip member  82  is positioned over the elongate rod  14  and over the proximal end  26  of the base  12 . The pin slots  94  of the forward grip member  82  are aligned with the base pinhole  36  and the rod pinhole  44  and the pin  86  is inserted through the aligned holes and slots. This secures the rod  14  to the base  12 , and mounts the forward grip member  82  to the rod and base for limited axial movement of the forward grip member  82  relative to the rod  14  and base  12 . 
         [0018]    The rearward grip member  84  is then mounted to the base  12  by screw threading the internal screw threads  108  at the distal end  106  of the rearward grip member onto the external screw threads  32  of the base. The rearward grip member  84  is screw threaded onto the base  12  until the distal end  106  of the rearward grip member  84  engages against the proximal end  88  of the forward grip member  82 . The rear cap  24  is then screw threaded into the internal screw threading  37  at the base proximal end  26 . The head  78  of the rear cap prevents the rearward grip member  84  from being removed from the instrument handle by screw threading the rearward grip member  84  off of the base  12 . 
         [0019]    With the instrument assembled as shown in  FIG. 1 , it should be appreciated that manually compressing the distal ends  92  of the forward grip member  82  will exert a compressive force on the conical sliding surface  66  of the ring  18 . This will cause the ring  18  to move axially toward the rod distal end  42 . This in turn causes the piston  16  to move through the piston slot  52  toward the rod distal end  42 . This movement of the piston will actuate the surgical instrument of a surgical instrument head of the type described in the earlier referenced U.S. patents. 
         [0020]    Releasing the manual compressive force on the distal end  92  of the forward grip member  82  will allow the piston  16  to move toward the rod proximal end  38  in response to the biasing force of the surgical instrument head attached to the instrument handle. This also results in movement of the ring  18  toward the rod proximal end  38 . As the ring  18  moves the ring proximal end face  66  pushes the forward grip member distal ends  92  back to their original positions. 
         [0021]    The novel construction of the instrument handle of the invention enables the radial spacing between the distal ends  92  of the forward grip member arms  102  to be adjusted to the desired comfort of the user. Turning the rearward grip member  84  in a first, clockwise direction relative to the forward grip member  82  will cause the forward grip member  82  to move axially along the rod  14 . The movement of the forward grip member  82  is determined by the length of the axial slots  94  in the forward grip member  82 . Movement of the forward grip member distal end  92  toward the rod distal end  42  will cause the distal ends  92  of the forward grip member arms  102  to expand radially outwardly as they slide over the ring proximal end surface  66 . Thus, this adjustably increases the radial spacing between diametrically opposite distal ends  92  of the forward grip member arms  102 . Rotating the rearward grip member  84  in a second, counterclockwise direction relative to the forward grip member  82  will allow the forward grip member  82  to move axially toward the proximal end  38  of the rod  14 . This allows the distal ends  92  of the forward grip member arms  102  to slide radially inwardly, over the ring proximal end surface  66 . This reduces the radial spacing between diametrically opposite distal ends  92  of the forward grip member arms  102 . 
         [0022]    Thus, in the manner discussed above, the instrument handle of the invention enables radially adjusting the width of the operative portion of the instrument handle adjacent the forward grip member distal ends  92  to suit the comfort of the user. 
         [0023]    Although a specific embodiment of the invention has been described above, it should be understood that other modifications and variations may be made to the invention without departing from the intended scope of protection provided by the following claims.