Comparison of intraoperative neurophysiological monitoring during spinal correction surgery between patients with congenital scoliosis and adolescent idiopathic scoliosis

English Keywords:Congenital scoliosis  Adolescence idiopathic scoliosis  Somatosensory evoked potentials  Motor evoked potentials  Intraspinal anomalies

English Abstract:

  【Abstract】 Objectives: To compare the intraoperative neurophysiological monitoring(IONM) results of posterior spinal correction surgery between congenital scoliosis(CS) and adolescent idiopathic scoliosis(AIS) patients and to investigate whether intraspinal anomalies are the risk factors of abnormal IONM data. Methods: A total of 67 CS patients receiving operation from June 2017 to October 2019 were retrospectively reviewed and 134 AIS patients at the same period were selected as control group. There was no significant difference in age (P=0.065) or Cobb angle of main curve(P=0.077) between the teo groups. The absolute values of latency and amplitude for somatosensory evoked potentials(SSEPs) and transcranial electric motor evoked potentials(TCeMEPs) in concave and convex sides, as well as the incidences of abnormal SSEPs were compared between CS and AIS patients. According to with or without intraspinal anomalies, CS patients were divided into two groups and between which the incidences of abnormal SSEPs were compared. Results: The SSEPs were all successfully obtained in 67(100%) CS patients, while TCeMEPs were successfully obtained in 66(98.5%), respectively; All SSEPs and TCeMEPs were successfully obtained in AIS patients. New neurologic deficits occurred in 3 CS patients and 1 AIS patients in the immediate postoperative period, and the sensitivity and specificity of IONM were not significantly different between the two groups. There was no significant difference in latencies of SSEPs-P37, SSEPs-N45 and amplitude of SSEPs and TCeMEPs between CS and AIS patients both in concave and convex sides(P>0.05). The incidences of abnormal SSEPs were not statistically different between CS and AIS groups(55.2% vs 42.5%, P=0.094). However, CS patients with intraspinal anomalies had significantly higher SSEPs-N45 latency in convex side(47.1±5.8ms vs 44.5±3.0ms, P=0.018) and higher incidence of abnormal SSEPs(80.0% vs 44.7%, P=0.017) than those of CS patients with no intraspinal anomalies. Conclusions: Similar IONM performance could be expected in CS patients without preoperative neurologic deficits compared with AIS patients. CS patients with intraspinal anomalies showed significantly higher SSEPs-N45 latency and higher risk of abnormal SSEPs than those without intraspinal anomalies.