Comparative analysis of sensory-motor function and its correlation with gait biomechanics in patients with unilateral...

This study was to evaluate the correlation between postural stability, proprioception, tactile sensation, and gait biomechanics in young patients with unilateral chronic ankle instability (CAI).

A total of 85 patients with CAI (80% females) and 51 healthy individuals (78% females) aged 18-35 years were recruited for this study. Standardized tests were used to assess bilateral sensory-motor function and gait biomechanics, to compare differences in sensory-motor function and gait biomechanics between groups, and to analyze the correlation between sensory-motor function and gait on the affected side of CAI patients. Postural stability was quantified by jump-landing test for stabilization time in the anterior-posterior direction; proprioception was quantified by bilateral thresholds for ankle plantarflexion, dorsiflexion, inversion, and eversion; and plantar sensation was determined by measuring the minimum thresholds of sensation in the five plantar regions. Gait biomechanics were analyzed by collecting ankle dorsiflexion-plantarflexion/inversion-exversion range of motion and ankle-toe kinetic parameters during barefoot walking.

Compared with Non-CAI, CAI patients had longer stabilization time in both anterior-posterior directions bilaterally (P = 0.015, P = 0.024); longer stabilization time was observed only in the medial-lateral direction on the affected side (P = 0.012). Thresholds for plantarflexion, dorsiflexion, inversion, and eversion of the ankle joint were higher bilaterally in CAI than in Non-CAI (all P < 0.05); tactile sensation was reduced bilaterally in CAI for the big toe, the 1st metatarsal head, the 5th metatarsal head, the lateral arch, and the heel (all P < 0.05); and gait biomechanics were reduced bilaterally in CAI patients than in Non-CAI individuals (all P < 0.05). Thresholds for plantarflexion, dorsiflexion, inversion, and eversion had significant negative correlations with gait biomechanics (r > 0.5, P < 0.05). There was a weak to moderate correlation between the lowest tactile sensation thresholds at the big toe and heel and gait biomechanics (r > 0.3, P < 0.05). No significant correlation was observed between stabilization time and gait biomechanics (P < 0.05).

Young patients with unilateral CAI have poor bilateral postural stability, proprioception and tactile deficits, and altered gait biomechanics. These changes not only affect the affected side but also involve the non-affected side.