1.Three-Dimensional Foot Shape Modelling Based on Statistical Shape Model
Qichang MEI ; Zixiang GAO ; FERNANDEZ JUSTIN ; Yaodong GU
Journal of Medical Biomechanics 2021;36(1):E096-E101
Objective To establish the three-dimensional (3D) statistical shape model (SSM) of the foot, so as to reveal the 3D foot shape variations. Methods Foot data from 50 normal Chinese young males were used for 3D statistical shape modelling. Steps, including mesh registration of foot surface, axis alignment and principal component (PC) analysis (dimension reduction), were performed to obtain the parameterized foot shape (mean shape and standard deviation of PC). Results Through the principal component analysis (PCA), the 3D foot shape varied in the length and width (PC1, 48.01%), arch and dorsal height (PC2, 11.38%), and hallux abduction-adduction position (PC3, 7.48%). Conclusions Based on the parameterised 3D foot SSM, these datasets can be applied into the population-based shoe last manufacture, orthotics customization and quick diagnosis of foot disorders in clinic.
2.Progress on Biomechanical Research of Image-Based Subject-Specific OpenSim Lower Extremity Musculoskeletal Model
Qichang MEI ; Yaodong GU ; Dong SUN ; Jianshe LI ; FERNANDEZ JUSTIN
Journal of Medical Biomechanics 2020;35(2):E259-E264
OpenSim musculoskeletal modelling has developed rapidly and been widely utilized due to its open-source. Apart from calculation of the basic kinematic and kinetic data, subject-specific OpenSim model could reveal information of neuromuscular control, muscle forces and geometry, and contact forces. Image-based model-ling of the neuromuscular control in pathological gait and ergonomic evaluation of the prostheses confirmed the reliability and feasibility, but limitations in time-consumption and foot-ankle modelling also existed. The subject-specific modelling of pathological gait could improve the accuracy and diversity of clinical biomechanics and medical engineering research. It could also reveal the pathological features, and provide scientific evidence to design specific and accurate protocols of motor function diagnosis and rehabilitation, health monitoring and evaluation, and ergonomic customization and assessment of devices, as well as future directions and implications in the research field.