  Pedicle screw insertion technique has made revolution in the surgical
treatment of spinal fractures and spinal disorders. Although X- ray fluoroscopy
based navigation is popular, there is risk of prolonged exposure to X- ray
radiation. Systems that have lower radiation risk are generally quite
expensive. The position and orientation of the drill is clinically very
important in pedicle screw fixation. In this paper, the position and
orientation of the marker on the drill is determined using pattern recognition
based methods, using geometric features, obtained from the input video sequence
taken from CCD camera. A search is then performed on the video frames after
preprocessing, to obtain the exact position and orientation of the drill.
Animated graphics, showing the instantaneous position and orientation of the
drill is then overlaid on the processed video for real time drill control and
navigation.
