Finite element analysis of the force changes of the supraspinatus tendon and glenohumeral joint during the abduction and flexion of the humerus

Zheng Wangyang; Fei Ji; Yang Di; Zhao Lang; Wang Lingli; Liu Peng; Li Haiyang

doi:10.12307/2026.098

Abstract：BACKGROUND:The shoulder joint is a complex and highly mobile joint in the human body.Its normal operation is crucial for daily life,but it is also prone to injuries.Diseases such as rotator cuff injuries,labral injuries,and dislocations are relatively common.Understanding the biomechanical characteristics of the shoulder joint is of great significance for the prevention and treatment of related diseases.Finite element analysis provides a powerful tool for such research. OBJECTIVE:To analyze the force changes of the supraspinatus tendon and glenohumeral joint during humeral abduction and flexion using finite element method. METHODS:A three-dimensional finite element model of the shoulder joint was constructed.The three-dimensional models of the humerus and scapula were extracted in Mimics software.They were processed and solidified in Geomagic software.In SolidWorks software,the models were assembled and models at different angles were established,and the supraspinatus tendon and articular cartilage were constructed.In Ansys software,material properties and contact relationships were set,and the stress changes of the supraspinatus tendon and articular cartilage were observed and analyzed. RESULTS AND CONCLUSION:(1)The type Ⅰ acromion morphology did not induce subacromial impingement syndrome when the humeral abduction angle was≤90°.(2)The stress of the supraspinatus tendon showed a non-linear increasing trend with the humeral abduction angle.(3)There was a significant positive correlation between the stress of the glenohumeral joint cartilage and the abduction/flexion angle.(4)The stress load of the articular cartilage in the abduction state was significantly higher than that in the flexion state(P＜0.01).(5)Through finite element analysis,this study for the first time revealed the biomechanical safety characteristics of the type Ⅰ acromion within the abduction range of 0°-90°,and quantified the stress-angle dynamic relationship of the supraspinatus tendon and the glenohumeral joint.However,due to model simplification and static analysis,the conclusions need to be verified by multi-modal in vivo experiments.Nevertheless,this study has laid an important theoretical foundation for the intervention strategy of related diseases.