Abstract: An instrument is provided for rotatably driving a screw or drill bit into bone in surgery, comprising a gear housing at a distal end of a drive shaft, wherein the drive shaft has a proximal end adapted for connection to a rotational power source, wherein the gear housing comprises at least one pair of bevel gears that direct the rotational force from the drive shaft in an approximately 115°-145° angle from the drive shaft to rotatably drive a screw or drill bit into bone during a surgical procedure. The device would advance or retract a drill or driver at a fixed angle in a manner that is user-friendly and ergonomic. The device addresses concerns with modern instrumentation that is cumbersome to use and does not allow the user generated forces to be efficiently applied to the intended trajectories.

Abstract: An instrument is provided for rotatably driving a screw or drill bit into bone in surgery, comprising a gear housing at a distal end of a drive shaft, wherein the drive shaft has a proximal end adapted for connection to a rotational power source, wherein the gear housing comprises at least one pair of bevel gears that direct the rotational force from the drive shaft in an approximately 115°-145° angle from the drive shaft to rotatably drive a screw or drill bit into bone during a surgical procedure. The device would advance or retract a drill or driver at a fixed angle in a manner that is user-friendly and ergonomic. The device addresses concerns with modern instrumentation that is cumbersome to use and does not allow the user generated forces to be efficiently applied to the intended trajectories.