Finite element analysis of the scoliotic spine under different loading conditions

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 degrees) 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 alteration, 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