[The application value of neuroelectrophysiological monitoring in posterior spinal corrective surgery for patients with osteochondrodysplasia complicated by kyphoscoliosis].

This study retrospectively analyzed the feasibility and influencing factors of intraoperative neurophysiological monitoring (IONM) during posterior corrective surgery in patients with achondroplasia (ACH) and kyphoscoliosis. A total of 22 ACH patients (10 males, 12 females) with kyphoscoliosis who underwent one-stage posterior spinal fusion at a single center from February 2010 to June 2023 were enrolled, with a mean age of (11.7±4.0) years. IONM parameters included latency and amplitude of somatosensory evoked potentials (SEP) from bilateral lower limbs, as well as latency and maximum amplitude of transcranial electric motor evoked potentials (MEP); side-to-side differences and the incidence of asymmetric SEP were calculated. Results showed that kyphosis was the most common deformity type (14 cases, 63.7%), and the apex vertebra was most frequently located at the thoracolumbar junction (15 cases, 68.2%); the mean preoperative maximum coronal Cobb angle was (71.9±26.3)°, and the mean maximum sagittal Cobb angle was (84.3±27.0)°. Baseline acquisition rates were 81.8% (18/22) for SEP and 72.7% (16/22) for MEP; intraoperative alerts occurred in 4 cases for SEP and 2 cases for MEP, with postoperative new neurological deficits in 2 cases. Sensitivity and specificity were 100.0% and 87.5% for SEP, and 100.0% and 92.8% for MEP, respectively. The mean side-to-side differences were (1.7±1.6) ms for SEP-P37 latency, (2.5±2.3) ms for SEP-N45 latency, (0.7±0.7) μV for SEP amplitude, (2.2±2.4) ms for MEP latency, and (174.7±150.3) μV for MEP amplitude; the incidence of abnormal SEP was 55.5% (10/18). It is concluded that IONM provides reliable monitoring value in deformity correction surgery for ACH patients with kyphoscoliosis; however, these patients commonly exhibit side-to-side asymmetry of IONM parameters and carry a higher risk of intraoperative positive events, which is closely associated with their inherent spinal stenosis, potential chronic spinal cord compression, and abnormal preoperative spinal cord morphology.