Non-Radiographic and Radiographic Predictors of Cobb Angle Progression in Adolescent Idiopathic Scoliosis

Predictive models for adolescent idiopathic scoliosis (AIS) frequently rely on radiographic measurements, exposing patients to cumulative radiation. Non-radiographic predictors such as passive range of motion (PROM) and 3D surface topography (3D ST) parameters remain underexplored. This study aimed to evaluate non-radiographic and radiographic variables associated with Cobb angle progression and develop stratified predictive models based on bracing status.

An IRB-approved retrospective review of AIS patients aged 10-18 with radiographic and 3D ST measurements was performed. Demographic, clinical, 3D ST, and bracing variables were collected. Curve change was defined as the difference between earliest and most recent Cobb angles. Univariate linear regression evaluated predictors of magnitude of Cobb angle change.

Fifty-seven patients with mean age of 13.6 years were included (braced n = 37; non-braced n = 20). Greater scoliotic angle and lumbar range of motion were significantly associated with Cobb angle progression in the overall cohort (p < 0.05). Among non-braced patients, scoliotic angle, female sex, and lumbar range of motion remained significant predictors (p < 0.05). No significant predictors were identified in the braced cohort.

Clinical assessments and 3D ST variables demonstrated associations with Cobb angle progression. These findings support development of radiation-free predictive models for AIS progression.