Biomechanical Simulation Of Achilles Tendon Of Take-off Leg During Hurdling

Purpose:Using the biomechanical simulation method based on Opensim softwarewhich combines motion capture and muscle-bone model techniques, thisstudy build the lower extremity model. The dynamic optimization methodwas adopted to calculate the muscle force and biomechanical analysis wasalso used on Achilles tendon (AT) loading and muscle-tendon unit (MTU)strain. comparing the AT loading and MTU strain between hurdling andrunning, this study analysis the mechanism of AT injury and explore theapplication of this simulation method to AT mechanical property.Theresults can provideA basis for the prevention of AT injury and the improvement of trainingmethod. This study can also be the foundation for further AT injuryresearch.Methods:Motion capture data was collected using VICON（infrared high-speedphotography system）, KISTLER（three dimension test force platform） andNORAXON(Telemyo DTS Surface Electromyography System). Ten male hurdlingathletes performed habitual right-leg takeoff hurdling running andsprinting trials. The Workstation and Bodybuilder software were used tomodeling and processing motion data. The Opensim software was adopted tosimulate and analysis the Achilles Tendon.The main parameter were asfollowing:Joint angle,Joint Moment,Ground Reaction Force,Muscle-TendonUnite Strain and Muscle Contribution to Acceleration of BodyCenter,Muscle Tendon Force.Excel2007was used to tabulate statisticsdata and draw graphs.Results:1) The simulation motions are fluent and approximal to real activity,besides the kinematic parameter and muscle activation results have nosignificant differences with the ground data.2) There are significant differences on ankle and knee of angle andmoment between take-off period. This results embody the different joint3) Muscle tendon unite are tensile and deformation during hurdling andsprinting,and the peak values are in different phase. Achilles Tendon peakforce appears at the end of stance phase and bear huge loading.Gastrocnemius contribute more to body center acceleration than soleus,especially in vertical direction. 4) Compared to traditional method, the simulation method based on Opensimsoftware is better on modeling, muscle force calculation and accuracytest.Conclusions:1) The results of Achilles Tendon biomechanical simulation based onOpensim software prove to accurate.2) Compared to sprint,the ground reaction force of hurdling is larger invertical direction. Hence Achilles Tendon bears huge impact force and morepotential to get injured.3) Achilles Tendon of hurdling is easier to get injured during take-offphase than sprint.4) Using the technique based Opensim software,There is no damagepotential for subject and data collecting and processing is moreconvenient. In addition, the open source type of the software provideconvenance for further research.