Quantifying Gait and Mobility in Severe Idiopathic Scoliosis with Inertial Measurement Technology

Background Adolescent idiopathic scoliosis (AIS) is the most common spinal deformity in adolescents. Severe curves (> 40°) can alter spinopelvic balance and gait mechanics, although few studies have objectively quantified these effects. To analyze gait characteristics, pelvic mobility, and lumbopelvic motion patterns in patients with severe AIS compared to healthy controls using inertial measurement unit (IMU) technology, and to explore correlations between radiological and gait parameters. Methods A prospective study was conducted including 35 preoperative AIS patients (Cobb > 40°) and 34 age-matched healthy controls. Each participant underwent gait analysis using a single IMU (BTS G-Sensor) performing three standardized tests: Up and Go , Walk , and 6-Minute Walk . Radiological parameters (Cobb angles, pelvic incidence, tilt, and sacral slope) were recorded. Statistical comparisons were performed. Results AIS patients showed significantly greater accelerations during standing-up and sitting-down transitions and reduced trunk flexion–extension ranges ( p  < 0.05). The control group exhibited greater gait symmetry and smaller pelvic tilt ranges. Gait speed and total distance in the 6-Minute Walk test were significantly lower in AIS patients ( p  < 0.05). Conclusions Severe AIS alters lumbopelvic rhythm and gait kinematics, producing compensatory patterns characterized by increased pelvic mobility and reduced trunk flexion. IMU-based motion analysis enables objective and reproducible evaluation of these biomechanical changes, offering a valuable clinical tool for preoperative assessment and rehabilitation planning.