Application Of ECG Monitoring In XLIF And Percutaneous Pedicle Screw Fixation

Objective:To discuss the application feasibility and clinical curative effect of electromyography (EMG) monitoring in extreme lateral interbody fusion (XLIF) and minimally invasive percutaneous pedicle screws osteosynthesis (MIPPSO)Method:61 cases of patients were undergone XLIF and MIPPSO where 32 cases were given EMG monitoring, the others weren’t monitoring. For monitoring group,spontaneous EMG monitoring was applied during establishment of XLIF channel to monitor whether there is extraction, irritability and stimulation on nerve root during the operation and to analyze and calculate the sensitivity and specificity of monitoring. All of patients were also cooperated with posterior percutaneous pedicle screw fixation in addition to XLIF, and intraoperative evoked EMG monitoring was used to monitor the implantation of pedicle screws. Pre-operative and postoperative JOA and ODI scores were compared, sensitivity and specificity of spontaneous and evoked EMG monitoring were calculated separately. Influence factors of EMG monitoring were observed to reduce the occurrence of false positives and false negatives.Results:A total of 31 cases of patients were effectively monitored during XLIF, where 11 appeared abnormal EMG reactions during operation which were disappeared after adjustment of operation, and 2 cases appeared abnormal wave which was recovered after a brief observation. Among the 30 patients without abnormal wave during channel establishment,1 cases appeared numbness and pain in front of the thigh.6 screws appeared EMG response after tapping even the intensity was less than 10mA, which have broken cortex of pedicle according to postoperative CT scan. The other 78 screws CT scan result are negative. Sensitivity and specificity of spontaneous EMG monitoring were 90.0% and 90.4%. Sensitivity and specificity of evoked EMG monitoring were 100% and 97.5%. Pre-operative JOA and ODI scores of monitoring group were 14.8±2.1、38.3±3.1, and postoperative JOA and ODI scores were 23.9± 2.6、13.6±2.9. Pre-operative JOA and ODI scores of control group were 14.3± 2.6、38.7±5.6, and postoperative JOA and ODI scores were 21.6±2.4、17.5± 4.3. Pre-operative JOA and ODI scores of monitoring group and control group had no difference (p>0.05), postoperative scores of them had significant difference (P<0.01)Conclusion:Intraoperative application of EMG monitoring in XLIF can obviously reduce the risk of nerve root injury, with high sensitivity and specificity.