Each of the four studies presented focus on the biomechanics of scoliosis deformity or treatment and products and devices which model or treat this condition. The main purpose of the four studies was to:​ characterize the trunk motion for the non-pathologic adolescent population, evaluate the trunk motion for the adolescent idiopathic scoliosis population, define the contribution of the scoliotic deformity to spinal motion changes, and biomechanically assess a scoliosis correction construct in a cadaver model. The first study determined there were no significant age related effects in spinal mobility and the only gender differences were located in the upper lumbar and torso region. The second study identified conflicting relationships between chronologic age and skeletal maturity and spinal mobility. Correlations of curve severity and spinal mobility varied depending on the spinal region and motion task. The third study determined scoliosis subjects have greater mobility in many spinal segments compared to their non-pathologic counterparts, especially in periapical regions. The fourth study identified very few significant biomechanical differences between an intact thoracic spine and rib cage and the same specimen with scoliosis correction instrumentation implanted. The results of these studies provide additional information regarding spine biomechanics in three models:​ in vivo nonpathologic adolescent thoracic and upper lumbar spine, in vivo scoliotic adolescent thoracic and upper lumbar spine, and adult cadaveric thoracic spine with and without an implanted rod construct.