Ankle biomechanics during multi-directional landings in athletes with chronic ankle instability

<p><strong>Background</strong></p> <p>Assessing and understanding the control of the ankle during multi-directional jump landings in athletes with chronic ankle instability (CAI) would help health professionals develop interventions to reduce the risk of recurrent injuries. The aim was to investigate the angle, angular velocity and moments of the ankle joint, and muscle activity of peroneus longus (PL), tibialis anterior (TA) and gastrocnemius (GAS) muscles during multi-directional landings in athletes with Chronic Ankle Instability (CAI).</p> <p><strong>Methods</strong></p> <p>Nineteen athletes with CAI (≤ 25 Cumberland Ankle Instability Tool -Thai Score) participated. A Vicon Nexus motion analysis system synchronously collected data with an AMTI forceplate and surface electromyography to capture kinematics, kinetics, and muscle activity, respectively. Participants were asked to perform single-leg jump-landing tests in forward (0°), 30° diagonal, 60° diagonal, and lateral (90°) directions. Ankle joint kinematics, kinetics, and muscle activity of PL, TA, and GAS were analysed. Repeated measure ANOVA and Freidman tests were used to analyse the main effects of jump-landing direction.</p> <p><strong>Results</strong></p> <p>Athletes with CAI exhibited significant differences in ankle angles, angular velocities, ankle moments, and average muscle activity of GAS between directions. Greatest average EMG of GAS muscle was observed during landing in lateral direction compared with forward and 30° diagonal directions.</p> <p><strong>Conclusion</strong></p> <p>Lateral and diagonal direction movements showed the greatest risks associated with recurrent ankle sprains. Impairment of neuromuscular control in both pre-landing and landing phases were observed in athletes with CAI when considered alongside previously published data.</p>