Acute effects of external visual feedback using cross-line laser on landing neuromechanics and postural control in chronic ankle instability.

Although neuromuscular training (NMT) programmes positively enhance clinical deficits in chronic ankle instability (CAI) patients, the effectiveness of NMTs in restoring movement patterns during jump landing is still questionable. Before developing new prolonged motor-learning interventions, it is important to determine the immediate effects of intervention on movement patterns during jump-landing in patients with CAI. Therefore, the purpose of this study was to determine whether real-time external feedback using a crossline laser device changes the movement patterns during jump-landing and balance tasks in patients with CAI. Eighteen patients with CAI completed three successful single-leg jump-landing tasks and single-leg balance tasks under the conditions of with and without external feedback. Lower-extremity joint angles, moments, and EMG activation of six muscles were collected during the single leg jump-landing task and centre of pressure data were collected during the single-leg balance test. Real-time external feedback allowed to change neuromechanical characteristics in the entire lower-extremity (i.e., ankle, knee, and hip joints) during jump-landing. However, there were no differences in static postural control between the two conditions. Clinicians should carefully consider incorporating a cost-effective laser device into an augmented NMT programme of longer duration to improve movement patterns during functional tasks in patients with CAI.