Multimodal intraoperative monitoring during surgery of spinal deformities in 217 patients.

A prospective study was performed on 217 patients who received MIOM during corrective surgery of spinal deformities between March 2000 and December 2005. Aim is to determine the sensitivity and specificity of MIOM techniques used to monitor spinal cord and nerve root function during corrective spine surgery. MIOM is becoming an increasingly used method of monitoring function during corrective spine surgery. The combination of monitoring of ascending and descending pathways may provide more sensitive and specific results giving immediate feedback information regarding any neurological deficits during the operation. Intraoperative somatosensory spinal and cerebral evoked potentials combined with continuous EMG and motor evoked potentials of the spinal cord and muscles were evaluated and compared with postoperative clinical neurological changes. A total of 217 consecutive patients with spinal deformities of different aetiologies were monitored by means of MIOM during the surgical procedure. Out of which 201 patients presented true negative findings while one patient presented false negative and three patients presented false positive findings. Twelve patients presented true positive findings where neurological deficit after the operation was predicted. All neurological deficits in those 12 patients recovered completely. The sensitivity of MIOM applied during surgery of spinal deformities has been calculated of 92.3% and the specificity 98.5%. Based upon the results of this study MIOM is an effective method of monitoring the spinal cord and nerve root function during corrective surgery of spinal deformities and consequently improves postoperative results. The Wake-up test for surgical procedure of spinal deformities became obsolete in our institution.