The use of mechanically elicited electromyograms to protect nerve roots during surgery for spinal degeneration.

Study Design. This study investigated the use of mechanically elicited electromyograms during the placement of pedicle screws in 89 patients undergoing surgery for spinal stenosis. Summary of Background Data. Several methods for monitoring nerve roots are available. However, mechanically elicited electromyograms may be more sensitive to mechanical irritation of nerve roots by pedicle screws than by other methods. Methods. Mechanically elicited electromyograms were recorded in muscle groups innervated by cervical or lumbar nerve roots