目的 利用有限元法对骨骼、躯干和矫形器之间的交互作用进行仿真模拟,评估增材制造脊柱侧弯矫形器的治疗效果。方法 结合患者的CT数据、躯干三维扫描模型和脊柱全长X光,建立骨骼-躯干-矫形器有限元模型并证明其有效性。计算在不同边界和载荷条件下,主胸弯脊柱侧弯Cobb角的变化及发展趋势。结果 增材制造矫形器治疗效果良好且随着矫形器预紧力的增加,Cobb角和骨盆倾斜的改善情况更加明显。预估70N预紧力作用于矫形器的6个月后,Cobb角将减少6.18°。在增加骨骼系统刚度的情况下,Cobb角改善不明显,甚至出现恶化。结论 脊柱侧弯矫形器能够有效地治疗骨骼尚在发育的青少年,对于骨骼发育成熟或产生退变的患者,矫形器治疗效果欠佳。
Objective To evaluate the efficacy of additive manufacturing scoliosis orthosis based on a simulation interaction of bone, trunk and orthosis with finite element method. Methods Combined with the CT data of the patients, the 3D scanning model of the trunk and the full length X-ray of the spine, the finite element model of the bone - trunk - orthosis was established and proved to be effective. The change and development trend of Cobb angle of main thoracic scoliosis were calculated under different boundary and load conditions. Results The treatment effect of the additive manufacturing scoliosis orthosis is good and the improvement of Cobb angle and pelvic tilt are more obvious with the increase of orthotic preload. The Cobb angle is expected to decrease by 6.18° after 6 months of applying a 70N preload to the orthosis. In the case of increasing system stiffness, Cobb angle improvement is not obvious, even worse. Conclusion Additive manufacturing scoliosis orthosis is effective in the treatment of adolescents with immature bones, while which may be less effective in patients with mature or degenerative bones.