The Influence of Dual Task and Gait Speed on Gait Variability in Patients With Chronic Ankle Instability

Inclusion Criteria: * history of at least one significant ankle sprain which occurred at least 12 months prior to enrolment in the study and was diagnosed by a physician or a physical therapist using clinical examination classifications described by Malliaropoulos et al * history of at least two episodes of 'giving way', and feelings of ankle joint instability in the previously injured ankle joint of 1 year post-initial sprain * the most recent injury occurred more than 6 weeks prior to the study enrolment * the ability to apply full weight bearing on the injured lower extremity with no more than mild discomfort Exclusion Criteria: * evidence of a concomitant injury (such as a bony injury or significant muscular/tendon injury) * previous ankle surgery * other pathological conditions or surgical procedures in lower extremity * neurological/vestibular or any other balance disorder. The control group included healthy participants with no current or previous conditions that could affect proprioception.