Correlation analysis between ankle proprioception and biomechanical characteristics in patients with chronic ankle instability.

PURPOSE: To compare ankle proprioception and biomechanical features between individuals with chronic ankle instability (CAI) and healthy controls, and to investigate the interplay between proprioceptive deficits and biomechanical alterations in CAI.

METHODS

Thirty-six male participants (18 CAI, 18 healthy controls) were recruited. Proprioception was evaluated using a joint position reproduction test, quantifying absolute errors. For biomechanical assessment, participants performed six single-leg hopping tests. An infrared motion-capture system (Vicon T40, 200 Hz) and a force platform (Kistler, 1,000 Hz) simultaneously captured ankle kinematics/kinetics. Ankle muscle activation was recorded via surface electromyography (Noraxon, 2,000 Hz).

RESULTS

Participants with CAI demonstrated significantly greater joint position sense errors in plantarflexion (P = 0.002), dorsiflexion (P = 0.001), inversion (P = 0.011), and eversion (P = 0.022) compared with controls. Compared with healthy controls, individuals with CAI exhibited greater peak ankle inversion angles (P = 0.039), reduced peak ankle dorsiflexion angles (P = 0.029), and lower activation of the tibialis anterior (P = 0.019) and peroneus longus (P = 0.033) during single-leg landing. Correlation analyses indicated significant associations between inversion position sense errors and both peak ankle dorsiflexion angle (r = -0.584, P = 0.011) and peak ankle inversion angle (r = -0.622, P = 0.006) in the CAI group.

CONCLUSIONS

Individuals with CAI exhibit impaired ankle proprioception and altered biomechanical characteristics compared with healthy controls. Decreased proprioception in the ankle was correlated with biomechanical defects. These findings suggest that proprioceptive impairments may contribute to persistent biomechanical abnormalities in CAI. Comprehensive interventions targeting proprioceptive enhancement may improve ankle biomechanics in this population.