Finite element analysis of the scoliotic spine under different loading conditions

Abstract

The role of the vertebral body`s rotation and the loading conditions of the brace has not been clearly identified in adolescent idiopathic scoliosis. This study aimed to implement a finite element (FE) model of C-type scoliotic spines to investigate the influence of different loading conditions on variations of Cobb`s angle and the vertebral rotation. The scoliotic FE model was constructed from C7 to L5, and its geometry was the right thoracic type (37.4°) with an apex over T7. Three loading conditions included a medial-lateral (ML) and anteroposterior (AP) force with a magnitudes of 100-0, 80-20 and 60-40 N. Those forces were respectively applied over the 6th, 7th and 8th ribs. According to an analysis of Cobb`s angle, the 100 N ML force that was applied over the 8th rib could achieve the best correction effect. Furthermore, the ML force was dominant in alterations of Cobb`s angle, whereas the AP force was dominant in alterations of the axial vertebral rotation. Additionally, the level below the apex was the most appropriate level to apply the force to correct C-type scoliosis. © 2010 IOS Press and the authors. All rights reserved.