Abstract: Objective To explore the relationship between the somatosensory evoked potential (SEP) diversification during operation and the short term outcome of ossification of posterior longitudinal ligament (OPLL) of cervical spine. Methods 70 OPLL inpatients from February 2008 to February 2011were included in this study. All patients received anterior cervical operation. According to the diversification of the SEP during surgery, the patients were divided into 2 groups. The preoperative and postoperative JOA scores of the OPLL patients were collected. Results There were 35 patients in the SEP no change group and 30 in SEP improved group. There was no difference in the preoperative JOA scores between them (P>0.05), but was significantly different in the postoperative JOA scores (P>0.05). Conclusion There is some relationship between the SEP diversification during operation and the short term outcome of OPLL of cervical spine.

Key words: cervical spine, ossification of the posterior longitudinal ligament, somatosensory evoked potential, Japanese Orthopaedic Association Scores