Finite Element Analysis of Anterior Talofibular Ligament under Different Strategies of Landing

Ankle injury research is typically performed with cadavers or by the clinical measuring technique which both of them have several problems such as general degradation of tissues. Numerical methods help us to overcome these problems. Therefore, the goal of this study was to compute the stress in Anterior Talofibular (ATF) ligament under different strategies of landing using finite element modeling for males and females. These strategies included the variation of the ankle flexion angle and hindfoot angle at the instant of initial contact with the ground.For calculating stress in ATF ligament, ankle torques were inputted to finite element model. Ankle torques were obtained from a five-link dynamic model using inverse dynamic approach. Input data for dynamic model included motion kinematics during drop landing from 60 cm height during 0.198 seconds after initial contact of the foot with the ground. Finite element model was created by manipulating of CT and MR images using the appropriate software. Results showed that stress in ATF ligament increase when torques in the ankle joint increase. Results from finite element model showed that when initial ankle with the ground was 68.7 degrees peak ATF ligament stress for females was lower than when initial ankle with the ground was 88.7 degrees. Additionally, increased initial plantar flexion of ankle leads to increasing stress up to 5.27 times in ATF ligament. Comparing this model and previous investigations’ results showed that this method is a useful tool to simulate landing condition for any person and to help us to predict whether those conditions probably lead to injuries or not.