Abstract:
Disclosed is a Rongeur for surgical use. The disclosed Rongeur has a push button actuator which, upon activation, allows the long parts of the Rongeur to be easily separated for thorough cleaning and sterilization for reuse.

Description:
GOVERNMENT SUPPORT 
     None. 
     RELATED APPLICATIONS 
     None. 
     FIELD OF THE INVENTION 
     The present invention relates generally to the field of medical instruments. Specifically, the present invention relates to an improved Rongeur having a push button actuator to allow the separation of its long parts to facilitate improved cleaning and sterilization. 
     DESCRIPTION OF THE RELATED ART 
     In surgical procedures, a Rongeur is used to remove a small amount of tissue or bone material. Critical to the reuse of Rongeurs in successive procedures, is the need to thoroughly clean the instrument of biological material and other contamination so as to thoroughly sterilize the instrument. A number of Rongeurs have been developed to facilitate the cleaning and sterilization of their various components. Designs for these Rongeurs include making them able to be disassembled, cleaned and sterilized, and reassembled for subsequent use. This requires skilled technicians and an extended time for cleaning. More recently, a Rongeur has been developed (U.S. Pat. No. 5,961,531, Weber) which allows the long parts of the Rongeur to be totally separated from each other such that the top long part of the Rongeur remains attached at an obtuse angle to the body of the Rongeur by an attachment means. While this is clearly an improvement over Rongeurs requiring disassembly and reassembly, it presents a complex design requiring, among other things, the release of its drive pin from its driving slot. 
     Accordingly, there is a need for a Rongeur that is simplified in structure with fewer parts, yet facilitates cleaning and sterilization for subsequent use by allowing direct access to the long parts of the Rongeur. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a Rongeur with a simpler, more elegant design with fewer parts which allows direct access to the parts in need of cleaning and sterilization by allowing the separation of those parts with a push button actuator. 
     In the present disclosure, a Rongeur is presented having a fixed bottom shaft and a movable top shaft (the long parts). The top shaft is slideably connected to and axially aligned with the fixed bottom shaft. The top shaft has a distal end with a cutting portion and a proximal end containing a cavity across which a drive pin is connected. Once the Rongeur is assembled, the drive pin remains captured by the driving hole of the front handle. When the push button actuator is activated, the movable top shaft is retracted slightly to allow the separation of the movable top shaft from the fixed bottom shaft to an acute angle there between. This allows full and direct access to the long parts for cleaning and sterilization. 
     While the present invention is directed to a more simplified Rongeur requiring fewer parts, while facilitating cleaning and sterilization, it may apply to various other specific types of Rongeurs. Moreover, the present invention also applies to other types of medical instruments that have inaccessible surfaces that are difficult to properly clean or sterilize. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the Rongeur in cutting position ready for use. 
         FIG. 2A  is a perspective view of the Rongeur with the moveable top shaft separated at an acute angle from the fixed bottom shaft and ready for cleaning. 
         FIG. 2B  is a cut away view of the cavity of the proximal end of the moveable top shaft of the Rongeur and of the slot of the fixed bottom shaft where it interacts with the front handle. 
         FIG. 3A  is an exploded view of the parts of the Rongeur. 
         FIG. 3B  is an enlarged exploded view the parts of the Rongeur. 
         FIG. 4  is a perspective view of the push button actuator of the Rongeur. 
         FIG. 5  is a cross sectional view of the push button actuator in the Rongeur. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a preferred embodiment of the disclosed invention in which top shaft ( 10 ) is in a normal cutting position relative to fixed bottom shaft ( 1 ), ready for use. Top shaft ( 10 ) is slideably connected to, and axially aligned with fixed bottom shaft ( 1 ). Top shaft ( 10 ) has a proximal end with a cutting edge ( 11 ) and a distal end containing a cavity ( 9 ) (shown in  FIG. 2B ) orthogonally transversed by drive pin ( 12 ). Fixed bottom shaft ( 1 ) has a proximal end with a foot plate ( 4 ) and a distal end forming rear handle ( 2 ). At the transition of bottom shaft ( 1 ) to rear handle ( 2 ) lies the interaction of front handle ( 13 ) with fixed bottom shaft ( 1 ) and push button actuator ( 20 ). Front handle ( 13 ) is pivotally attached to rear handle ( 2 ) and is held in the open or normal position by lever spring ( 5 ). Lever spring ( 5 ) resists against the compression of front handle ( 13 ) toward rear handle ( 2 ) and keeps the Rongeur in normal position. Top shaft ( 10 ), when slidingly engaged with fixed bottom shaft ( 1 ) as shown in  FIG. 1 , may be retracted slightly by depressing the push button actuator ( 20 ) which allows the separation of top shaft ( 10 ) from fixed bottom shaft ( 1 ) to at least an acute angle ( 40 ) (shown in  FIG. 2A ). Also shown in  FIG. 2A , is slot ( 3 ) which is medially centered on fixed bottom shaft ( 1 ) at its transition to rear handle ( 2 ). The separation of top shaft ( 10 ) from fixed bottom shaft ( 1 ) at angle ( 40 ) allows direct access to all surfaces of the long parts of the Rongeur for cleaning and sterilization. Once cleaning and sterilization occurs, simply returning top shaft ( 10 ) to slideable connection with fixed bottom shaft ( 1 ) returns Rongeur to fully operable condition and ready for the next use. 
     Depicted in  FIG. 3A , front handle ( 13 ) has a proximal end ( 15 ) containing drive hole ( 14 ) and a distal end forming front handle ( 13 ) of the Rongeur. Turning to  FIG. 2B , the proximal end ( 15 ) of front handle ( 13 ) is fitted through slot ( 3 ) of fixed bottom shaft ( 1 ) and into cavity ( 9 ) of top shaft ( 10 ) whereby drive hole ( 14 ) receives drive pin ( 12 ). In this simple design, once the Rongeur is assembled, drive pin ( 12 ) is never released from drive hole ( 14 ) during the use of the Rongeur in a medical procedure or thereafter in an activated position during cleaning and sterilization.  FIGS. 3A and 3B  further show the parts of the push button Rongeur. The proximal end ( 15 ) of front handle ( 13 ) has rear surface ( 16 ) which contacts actuator shaft ( 23 ) (shown in  FIG. 4 ) when the push button actuator ( 20 ) is in normal position and ready for use. 
       FIG. 4  shows the structure of push button actuator ( 20 ). Push button actuator ( 20 ) is comprised of a compression spring ( 21 ) and shaft ( 23 ) containing groove ( 22 ). 
     Shown in  FIG. 5  is a cross section of the push button actuator ( 20 ) in normal position before actuation. The push button actuator ( 20 ) is operably connected to fixed bottom shaft ( 1 ). Compression spring  21  has a distal end ( 28 ) attached to an inner wall in slot ( 3 ) of fixed bottom shaft ( 1 ) and a proximal end ( 29 ) contacting push button actuator ( 20 ). Before activation, compression spring ( 21 ) is extended holding push button actuator ( 20 ) in its normal position. Push button actuator ( 20 ) is depressed to an activated position (not shown) by pushing push button actuator ( 20 ) toward fixed bottom shaft ( 1 ) [the direction shown by arrow ( 25 )], thereby compressing compression spring ( 21 ). On actuation of push button actuator ( 20 ), rear surface ( 16 ) of front handle ( 13 ) ( FIG. 3B ) slips into groove ( 22 ), thereby allowing top shaft ( 10 ), which is engaged with drive pin ( 12 ) through drive hole ( 14 ) in the proximal end of front handle ( 13 ), to be slightly retracted from the outer circumference of shaft ( 23 ), to contact the surface of groove ( 22 ). Top shaft ( 10 ) may then be separated from fixed bottom shaft ( 1 ) to an angle ( 40 ) (shown in  FIG. 2 ). The separation of top shaft ( 10 ) from fixed bottom shaft ( 1 ) to angle ( 40 ) makes the parts of the Rongeur readily accessible for cleaning and sterilization. This separation of the long parts to angle ( 40 ) is facilitated by the movement of drive pin ( 12 ) within drive hole ( 14 ) which is elongated to accommodate the movement of drive pin ( 12 ). Drive pin ( 12 ) remains captured by drive hole ( 14 ) at all times while the Rongeur is in use and while is long parts are separated for cleaning. 
     After cleaning, top shaft ( 10 ) is returned to contact with fixed bottom shaft ( 1 ), compression spring ( 21 ) returns push button actuator ( 20 ) to its normal position, and the Rongeur is ready for use ( FIG. 1 ). When ready for use, top shaft ( 10 ) is slideably connected to fixed bottom shaft ( 1 ) and held in a forward position by the contact of rear surface ( 16 ) of front handle ( 13 ) ( FIG. 3B ) with shaft ( 23 ) of push button activator ( 20 ) ( FIGS. 4 and 5 ). 
     The foregoing detail of the disclosed embodiment of the push button Rongeur is not intended as a limitation on other configurations of the push button actuator which may be apparent to those skilled in the art without departing from the scope and spirit of the disclosed invention as defined in the following claims.