Finite element simulation of scoliosis with muscle unit introduction:verification of correction effect under bidirectional load

Wu Hongxu; Liu Xuanyu; Wang Taoyu; Wang Shiyao; Cheng Jingyi; Zhang Mingwen; Zhang Yinxia; Liu Zhihua; Wang Xiaojie

doi:10.12307/2026.116

Abstract：BACKGROUND:At present,conservative treatments for scoliosis mainly include physical therapy,brace correction,and traction.In clinical practice,as much traction as possible is usually used within the tolerance range of the patient,and as the tolerance increases,the traction will also increase. OBJECTIVE:To establish a three-dimensional finite element model of scoliosis,incorporating muscle units to enhance realism,and investigate the therapeutic efficacy of a scoliosis correction system with bidirectional(axial and lateral)corrective loads.By analyzing the interaction between axial traction and lateral pushing forces,the study explores how corrective forces influence the Cobb angle,providing a theoretical basis for optimizing individualized treatment plans. METHODS:Spinal CT scan data from a scoliosis patient aged 35 years old were used to construct a 3D finite element model using Mimics,Geomagic Wrap,and HyperMesh software,with muscle units integrated.Finite element analysis was performed via Abaqus.The therapeutic effects of axial traction and lateral pushing loads—applied individually and in combination—were evaluated.Additionally,the impact of periodic lateral loading on treatment efficacy was studied,and a mathematical model of the moments generated by the two loads was developed for computational analysis. RESULTS AND CONCLUSION:(1)When axial traction load combined with lateral push load,the correction rate of scoliosis treatment was 22%in the thoracic segment and 24%in the lumbar segment,respectively,which was better than the two effects alone,and the correction rate was further increased to 27%and 29%with the addition of periodic lateral load.(2)There was a certain relationship between the effect of the two kinds of loads and the Cobb angle.When the Cobb angle was less than 53.13°,the effect of the lateral load was better than that of the axial load.When the Cobb angle was more than 53.13°,the effect of the axial load was better than that of the lateral load,which provided a mechanical theoretical basis for the sequence of application of the two kinds of orthopedic forces.(3)These results provide theoretical support for the development of patient personalized treatment to ensure the safety and effectiveness of orthopedic forces.