Effect of Asymmetric Tension on Biomechanics and Metabolism of Vertebral Epiphyseal Plate in a Rodent Model of Scoliosis

Objective To investigate the effect of asymmetric tension on idiopathic scoliosis (IS) and to understand its pathogenic mechanism. Methods The rodent model of scoliosis was established using Sprague–Dawley rats with left rib-tethering from T6 to T12, tail and shoulder amputation, and high-cage feeding. Vertebrae epiphyseal cartilage plates were harvested from the convex and concave sides. To analyze differences on the convex and concave sides, finite element analysis was carried out to determine the mechanical stress. Protein expression on epiphyseal cartilage was evaluated by western blot. Micro-CT was taken to evaluate the bone quality of vertebral on both sides. Results Scoliosis curves presented in X-ray radiographs of the rats. Finite element analysis was carried out on the axial and transverse tension of the spine. Stresses of the convex side were −170.14, −373.18, and −3832.32 MPa (X, Y, and Z axis, respectively), while the concave side showed stresses of 361.99, 605.55, and 3661.95 MPa. Collagen type II, collagen type X, Sox 9, RunX2, VEGF, and aggrecan were expressed significantly more on the convex side (P