Chapter 13 - Electromyographic monitoring for pedicle screw placements

Abstract

The use of pedicle screws for spinal stabilization has become commonplace during different spinal surgical procedures. However despite the usage of surgical inspection and imaging techniques, the placement of these screws is largely performed blindly. The incidence of misplaced pedicle screws resulting in neurological impairment has been reported to be quite high even with experienced surgeons. New imaging techniques may help to reduce the incidence of misplaced hardware but they are still not free from error. As a result surgeons and clinical neurophysiologists have utilized electrophysiological monitoring techniques for assessing nerve root function and pedicle screw placement during surgery. Based on the published results of numerous investigators, the combined use of spontaneous and triggered myogenic activity for intraoperative monitoring during pedicle screw placement has been shown to be practical, cost effective, and improves surgical outcomes.