Tool and set screw for use in spinal implant systems

Abstract

The present invention relates to a tool in combination with a set screw for use in spinal implant systems, and more particularly to a tool for the deployment of set screws with a break-off neck portion comprising a handle portion, a stem portion extending from the handle portion, a set screw retaining means, and a driving means extending from the stem portion and disposed opposite the handle portion. The driving means is adapted to allow the installation of the set screw to the bone and applying torque for the shearing of the neck portion thereof, and at the same time is adapted to remove the installed screw portion of the said set screw when needed.

1 - 12 . (canceled) 
     
     
         13 . In combination, a tool with a set screw for use in spinal implant systems, comprising:
 a tool having a handle portion and a stem portion extending from said handle portion;   a set screw having an axial bore, a head portion, a break-off neck portion and a threaded screw portion extending from said neck portion, wherein said head portion comprises a plurality of substantially V-shaped internal notches formed along the surface thereof, and wherein said threaded screw portion comprises an external thread and a plurality of substantially V-shaped internal notches formed along the surface thereof;   a retaining means provided on said tool to allow handling and installation of said set screw; and   a driving means provided on said tool to allow the installation of said set screw to a bone screw or hook, apply torque for the shearing of the neck portion of said set screw, and remove the installed screw portion of said set screw on said bone screw or hook.   
     
     
         14 . In combination, a tool with a set screw for use in spinal implant systems according to  claim 13 , wherein said driving means comprising a first protrusion extending axially from the end portion of said stem portion opposite said handle portion, and a reduced second protrusion extending axially from said first protrusion, said first protrusion being provided with a plurality of substantially V-shaped projections to engage with said internal V-shaped notches in head portion of said set screw, and said second protrusion being provided with a plurality of adjacent substantially V-shaped projections formed along the surfaces thereof to engage with said internal V-shaped notches in threaded screw portion of said set screw. 
     
     
         15 . In combination, a tool with a set screw for use in spinal implant systems, comprising:
 a tool having a handle portion and a stem portion extending from said handle portion;   a set screw having an axial bore, a head portion, a break-off neck portion and a threaded screw portion extending from said neck portion, wherein said head portion comprises a plurality of substantially V-shaped external projections formed along the surface thereof, and wherein said threaded screw portion comprises an external thread and a plurality of substantially V-shaped internal notches formed along the surface thereof;   a retaining means provided on said tool to allow handling and installation of said set screw; and   a driving means provided on said tool to allow the installation of said set screw to a bone screw or hook, apply torque for the shearing of the neck portion of said set screw, and remove the installed screw portion of said set screw on said bone screw or hook.   
     
     
         16 . In combination, a tool with a set screw for use in spinal implant systems according to  claim 15 , wherein said driving means on said tool comprising a cavity extending axially from the end portion of said stem portion opposite said handle portion, and a reduced protrusion extending axially from said cavity, said cavity being provided with a plurality of adjacent substantially V-shaped internal notches formed along the surface thereof to engage with said external V-shaped projections on said set screw, and said reduced protrusion being provided with a plurality of adjacent substantially V-shaped projections formed along the surface thereof to engage with said internal V-shaped notches in said set screw. 
     
     
         17 . A method of installing, tightening and loosening a setscrew on a spinal bone screw or hook, comprising the steps of:
 providing a tool having a handle portion and a stem portion extending from said handle portion, said tool having a retaining means and a driving means for a set screw;   providing a set screw having an axial bore, a head portion, a break-off neck portion and a threaded screw portion extending from said neck portion, wherein said head portion comprises one of a plurality of substantially V-shaped internal notches and a plurality of substantially V-shaped external projections formed along the surface thereof, and wherein said threaded screw portion comprises an external thread and a plurality of substantially V-shaped internal notches formed along the surface thereof;   attaching and retaining said set screw on said tool;   tightening the set screw on a spinal bone screw or hook by shearing off the head portion of said set screw at the break-off neck portion using said tool;   removing the sheared off head portion from said tool; and   loosening, when needed, the threaded screw portion of said set screw from the spinal bone screw or hook using said tool.