Patients undergoing spinal fusion procedures are also at risk for perioperative neurologic injury. Surgeons at CHOP and other institutions routinely utilize neurophysiologists to evaluate at-risk neural pathways to identify impending spinal cord and spinal nerve root injury. These consultants monitor motor and sensory pathways by recording and analyzing evoked potentials and electromyography during the operation. Evoked potentials are low voltage electrical signals generated in response to transcranial or transcutaneous electrical stimulation of motor and sensory nerves.