Keywords: آگونم های آلفا 2 آدرنرژیک; Alpha-2 adrenergic agonists; Clonidine; Cortico-spinal motor pathways; Neuromonitoring; Postoperative pain; Scoliosis surgery; Somatosensory evoked potentials; Total intravenous anesthesia; Transcranial electrical motor evoked potentials;