Combined monitoring of motor and somatosensory evoked potentials in spinal deformity surgery

English Keywords:Cortical somatosensory evoked potential  Motor evoked potentials  Intra-operative monitoring

English Abstract:

  【Abstract】 Objective：To investigate the efficacy of combined monitoring of motor evoked potentials with trans-cranial electrical stimulation（TES-MEP） and cortical somatosensory evoked potentials（CSEP） for spinal deformity correction surgery．Method：There were 37 patients including 25 males and 12 females（group A）.The average age was 26.1 years old．There were 17 cases of scoliosis，and 20 cases of kyphosis deformity．All patients underwent intra-operative CSEP and MEP monitoring．Twenty-nine cases（10 males and 19 females） who experienced only CSEP monitoring were termed as control group（group B）．The average age was 15.8 years old．For those with amplitude decreasing 50% and latency increasing 10% or remaining no change with stimulate 100V over than primary，surgical approach were changed．Result：Combined motor and sensory monitoring was successfully achieved in 32 （86.4%） cases in group A．The abnormality of CSEP was observed in 4 cases（10.8%），while the abnormality of MEP was observed in 19 cases（60%）.The abnormality of CSEP and TES-MEP occurred in 4 cases（10.8%），abnormal MEP with abnormal CSEP occurred in 15 cases（40.5%）.No case in group A with normal intra-operative monitoring was complicated with post-operative neurological deficit（0%）.Two cases with kyphosis deformity due to old TB and fracture were noted MEP and/or CSEP abnormality，and the patients had minor neurological deficit after surgery．In group B，9 cases（21%）were noted CSEP abnormal．3 cases（10%）with normal recordings were complicatred with severe motor dysfunction．Conclusion：Combined TES-MEP and CSEP in spinal deformity surgery is safe，reliable and sensitive for monitoring spinal cord function，which can be used to guide surgery.