Determination of In Vivo Dynamic Human Ankle Stiffness Under External Foot Rotation

Ankle sprains account for 10–15% of all sports injuries [1]. Understanding the conditions that contribute to sports-related ankle sprains can provide useful information to footwear designers to help prevent such injuries. Attempts have been made to create surrogate ankles that mimic ankle properties in order to simulate injury scenarios. In this laboratory, using data from cadaver experiments, Villwock et al. developed such an ankle to assess injury risk due to shoe-surface interface [2]. While this model provides data on shoe-surface interactions, it only takes into account ankle stiffness in rotation. Consequently, the model can only recreate internal-external rotation, not eversion-inversion or plantarflexion-dorsiflexion responses of the human ankle.