Comparison of intraoperative neurophysiologic monitoring outcomes between cervical and thoracic spine surgery.

PURPOSE: The objective is to compare the intraoperative monitoring (IOM) outcomes between degenerative cervical and thoracic spine decompression surgery.

METHOD: A total of 97 patients with cervical compression myelopathy (CCM) and 75 patients with thoracic compression myelopathy (TCM) were prospectively collected between December 2012 and June 2015 in our spine center. Somatosensory-evoked potentials (SSEP) and motor-evoked potentials (MEP) were used for IOM. The postoperative neurologic status of each patient was assessed immediately after surgery. And the IOM and neurological outcomes were mainly analyzed in this study.

RESULTS: Under the same alarm criteria, the IOM changes present significant difference between the cervical and thoracic surgery. During the patients with monitoring alerts, the MEPs usually manifest as sudden loss in TCM whereas the gradual loss in CCM. And there were three permanent neurologic injuries in the thoracic cases, but none in cervical cases.

CONCLUSION: The IOM loss between CCM and TCM patients present obvious difference and the sudden MEPs loss associated with spinal decompression need to be taken seriously especially in TCM.