Abstract
OBJECTIVE: This study compared the intraoperative neurophysiological monitoring (IONM) data between patients with Marfan syndrome (MFS) scoliosis undergoing posterior spinal correction surgery and those with idiopathic scoliosis (IS). METHODS: Patients diagnosed with MFS who underwent posterior spinal correction surgery between January 2018 and December 2023 were reviewed. Patients with IS who underwent posterior spinal correction surgery were randomly selected as the control group. Motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SEPs) were measured separately on the convex and concave sides of the main curve. We recorded IONM failure and asymmetrical SEPs waveforms. For each patient, we assessed the apical vertebral translation, Cobb angle of the main curve, curve pattern, deformity angular ratio (DAR), and global kyphosis. Independent-sample t-test and chi-square tests were conducted to compare differences between the IS and MFS groups. RESULTS: We included 238 girls with IS and 118 patients with MFS scoliosis (45 men and 73 women). The rates of MEPs and SEPs were 95.4% and 93.7% in girls with IS, and 92.4% and 89.8% in patients with MFS scoliosis, respectively. In the MFS group, the average N45 latency, P37 latency, and amplitude of SEPs were 49.5 ± 3.9 ms, 39.9 ± 3.5 ms, and 2.5 ± 1.4 μV on the convex side and 50.1 ± 4.0 ms, 39.9 ± 3.5 ms, and 2.4 ± 1.3 μV on the concave side, respectively. The MEP amplitude was 731.7 ± 734.3 μV on the concave side and 854.3 ± 778.2 μV on the convex side. Patients in the IS group had lower SEP-N45 and SEP-P37 latencies than the patients in the MFS group (p < 0.001). Asymmetrical SEPs were observed in 102 patients in the IS group and 52 patients in the MFS group, respectively (p = 0.879). IONM waveform failure was identified in 21 patients in the IS group and 17 patients in the MFS group, respectively (p = 0.108). IONM failure was more likely in patients with a larger C-DAR, S-DAR, T-DAR, and Cobb angle of the main curve preoperatively (p = 0.017, 0.005, 0.001, and 0.001, respectively). CONCLUSIONS: In patients with MFS scoliosis, the success rates of MEPs and SEPs during posterior spinal fusion were 92.4% and 89.8%. Compared to MFS patients, those with IS demonstrated shorter SEP latencies, with similar MEP and SEP amplitudes. MFS patients with higher DAR values and larger Cobb angles of the main curve preoperatively were at a higher risk of IONM failure.