2018 Volume 33 Issue 1 Pages 59-64
[Purpose] To analyze the kinematics of the foot and ankle, and muscle activities during single-leg lateral drop landing of individuals with histories of ankle sprain. [Subjects and Methods] Twenty individuals with histories of ankle sprain (past history group, 11 males, 9 females, mean age: 21.2) and another twenty individuals without any history of ankle sprain (no history group, 12 males, 8 females, mean age: 21.2) were enrolled in this study. Subjects landed on a single-leg, after dropping from a 30-cm high platform to the lateral side floor 30 cm from the platform. Plantar and dorsal flexion angles of the ankle joint, pronation and supination angles of the hindfoot, and muscle activities of the lower legs were measured. [Results] The plantar flexion angle before landing, the supination angle, and tibialis anterior activity after landing in the past history group were significantly higher than those in the no history group. [Conclusion] Higher activity of the tibialis anterior is considered to be related to excessive supination. These findings may indicate that excessive supination during side landing increases the risk of recurrence of ankle sprain.