A Stereotactic/Robotic System for Pedicle Screw Placement

. We are developing a robotic system to assist a surgeon in placing spinal pedicle screws. While several groups have undertaken such systems, our approach differs in that it endeavors to remain as close to current clinical technique as possible, yet achieve stereotactic accuracy. This paper describes the conventional surgical methodology, justifies the need for stereotactic/robotic assistance, and discusses the various approaches to system design. In describing our system design, we emphasize key issues that arise with regard to robot accuracy, image linearity, and system registration. 1. Pedicle Screw Placement Surgery 1.1 Conventional Methodology Currently about 60,000 lumbosacral fusions are performed a year in the United States using a variety of different surgical techniques and instrumentation. These various surgical techniques, though different, follow a similar methodology. The patient is in a prone position and the surgical approach is posterior. The vertebral grooves have to..