Comparison of intraoperative neurophysiological monitoring between patients with arthrogryposis multiplex congenita and adolescent idiopathic scoliosis

Abstract

Objective: To compare the intraoperative neurophysiological monitoring (IONM) results between patients with arthrogryposis multiplex congenita (AMC) and adolescent idiopathic scoliosis (AIS) and to analyze the influence of congenital spinal deformity on IONM in AMC patients, thus to evaluate the efficiency of IONM in AMC patients. Methods: A cross-sectional study. The clinical data of 19 AMC patients underwent correction surgery from July 2013 to January 2022 in Nanjing Drum Tower Hospital were retrospectively reviewed. There were 13 males and 6 females with a mean age of (15.2±5.6) years, and the average Cobb angle of main curve was 60.8°±27.7°. And 57 female AIS patients of similar age and curve type with the AMC patients during the same period were selected as the control group, with an average age of (14.6±4.4) years and a mean Cobb angle of 55.2°±14.2°. The latency and amplitude of samatosensory evoked potentials (SSEPs) and transcranial electric motor evoked potentials (TCeMEPs) were compared between the two groups. The difference in IONM data between AMC patients with and without congenital spinal deformity was also evaluated. Results: The success rates of SSEPs and TCeMEPs were 100% and 14/19 for AMC patients, 100% and 100% for AIS patients. The SSEPs-P40 latency, SSEPs-N50 latency, SSEPs-amplitude, TCeMEPs-latency, TCeMEPs-amplitude showed no significant difference between AMC patients and AIS patients (P>0.05 for all). The side-difference of TCeMEPs-amplitude showed an increasing trend in AMC patients when compared with that in AIS patients, but there was no statistical difference between the two groups [(147.0±185.6) μV vs (68.1±311.4) μV, P=0.198]. The SSEPs-amplitude value was (1.4±1.1) μV on concave side in AMC patients with congenital spinal deformity, and it was (2.6±1.2) μV on concave side in AMC patients without congenital spinal deformity (P=0.041). The SSEPs-amplitude value was (1.4±0.8) μV on convex side in AMC patients with congenital spinal deformity, and it was (2.6±1.3) μV on convex side in AMC patients without congenital spinal deformity (P=0.028). Conclusions: The values of SSEPs-P40 latency, SSEPs-N50 latency, SSEPs-amplitude, TCeMEPs-latency and TCeMEPs-amplitude are similar in AMC and AIS patients. The SSEPs-amplitude of AMC patients with congenital spinal deformity is lower than that of AMC patients without congenital spinal deformity.