US Patent 9526553 Screw insertion instrument

An instrument for selectively coupling with a pedicle screw is disclosed. The instrument includes an inner shaft, wherein the distal tip is configured to engage a pedicle screw and the proximal end configured to be selectively engaged with a knob, and a knob assembly configured to advance over the inner shaft, wherein the distal end is configured to engage the tulip of the pedicle screw and the proximal end is configured to selectively engage the inner shaft. A method for selectively coupling the instrument to a pedicle screw is also disclosed.