Surgical treatment for spinal cord lesions carries a high risk of postoperative neurological deficits. Intraoperative neurophysiological monitoring has been developed to reduce such risks. Initially, somatosensory evoked potential (SEP) monitoring was successfully used in deformity correction surgery. Its major disadvantage was its inability to detect partial spinal cord damage affecting motor pathways. Motor evoked potential (MEP) monitoring was later developed to overcome this deficit of SEP monitoring. Both SEP and MEP monitoring were highly accurate in predicting postoperative neurological deficits in deformity correction surgery and were later introduced into surgery for intramedullary tumors (IMTs). These monitoring techniques provide accurate predictions in patients with intact neurologic function, but are prone to false positives when patients have compromised neurologic function. Some studies overemphasize the usefulness of intraoperative neurophysiological monitoring in surgical treatment for IMTs. We review the current understanding of neuroanatomy and physiology and the realistic utility and limitations of intraoperative neurophysiological monitoring during surgery for IMTs.