BACKGROUND:Unilateral chronic ankle instability has adverse effects on the affected limb,and evidence has shown that the nonaffected side may be similarly involved,but direct evidence is currently lacking.OBJECTIVE:To investigate the effects of unilateral chronic ankle instability on bilateral postural stability,proprioception,plantar tactile sensation,and muscle strength.METHODS:A total of 122 participants were recruited in this study,including 67 individuals with unilateral chronic ankle instability and 55 individuals without chronic ankle instability.Postural stability,proprioception,plantar tactile sensation and muscle strength were tested bilaterally in individuals with unilateral chronic ankle instability,as well as in those without chronic ankle instability.One-way analysis of variance or Kruskal-Wallis test was used for intergroup comparisons.RESULTS AND CONCLUSION:(1)Compared with individuals without chronic ankle instability,individuals with chronic ankle instability had longer time to stability in the anterior-posterior direction bilaterally(P=0.001-0.012),and longer time to stability in the medial-lateral direction on the affected side(P=0.012-0.025);had higher proprioception thresholds of plantarflexion,dorsiflexion,inversion,and eversion of the bilateral ankles(P=0.000-0.035);showed lower tactile sensation sensitivities of the bilateral great toe,first metatarsal head,fifth metatarsal head,arch,and heel(P=0.000-0.008);and had weaker muscle strength for inversion and eversion of the bilateral ankles(P=0.000-0.019).(2)Individuals with unilateral chronic ankle instability have bilateral deficits in postural stability,proprioception,plantar tactile sensation,and muscle strength.Therefore,the rehabilitation needs of both limbs should be fully considered when treating chronic ankle instability.
bilateral deficitschronic ankle instabilityankle sprainsensorimotorbalance controlproprioceptionplantar cutaneous sensationengineered tissue construction