Effect of Spinal Morphological Changes on Gait Characteristics in Patients with Adolescent Idiopathic Scoliosis: Gait Analysis Using an Inertial Measurement Unit

This study investigated the relationship between morphological changes in the spine and gait characteristics in patients with adolescent idiopathic scoliosis (AIS) through inertial measurement unit (IMU) analysis. Twenty-three female patients with AIS scheduled for scoliosis surgery underwent preoperative gait analysis with an IMU attached at the third lumbar vertebra. Gait stability indicators including root mean square (RMS) values for the mediolateral (RMSx), anteroposterior, and vertical components were calculated. The peak mediolateral components in the four coronal plane quadrants were also analyzed. Relationships with the main thoracic (MT) curve, thoracolumbar curve, and thoracic kyphosis (TK) were assessed using Spearman’s rank correlation. The MT curve positively correlated with RMSx, whereas TK exhibited a negative correlation. Gait symmetry analysis revealed a positive correlation between the MT curve and peak mediolateral trunk acceleration in the second (left-upper) quadrant and negative correlations for TK in the first (right-upper) and fourth (right-lower) quadrants. Patients with AIS with right-convex MT curves shifted their center of gravity leftward, but reduced TK restricted this compensation. These findings may be useful in developing the rehabilitation strategies for AIS.