A study of 5,206 adolescent idiopathic scoliosis (AIS) patients undergoing spinal fusion with multimodal intraoperative neuromonitoring (IONM) found alerts occurred in 5% of cases, most frequently in Lenke Type-4 curves and least in Type-5 curves. The study reported that larger preoperative major Cobb angle was the leading independent risk factor for alerts, hypotension was the most common triggering event, and neurologic deficits occurred in 4% of alert patients versus under 1% of those without alerts; alert status did not independently affect 2-year Cobb angle correction.