Masumeh Hallaj Mazidluie - Department of Physiotherapy, Faculty of Rehabilitation Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Jalal Ahadi - Department of Physiotherapy, Faculty of Rehabilitation Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Fatemeh Oraei Eslami - Department of Physiotherapy, Faculty of Rehabilitation Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Tabasom Ghanavati - Department of physiotherapy, Faculty of Rehabilitation Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Amin Moradi - Department of Orthopedics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

Objectives: The anterior cruciate ligament (ACL) reconstruction surgery improves mechanical stability; however, functional stability remains impaired. Balance exercises can help improve functional stability. The effect of cognitive dual-task balance exercises has not been studied in people with ACL reconstruction surgery; therefore, this study aimed to compare the effect of cognitive dual -task and single-task balance exercises on the static balance indices in these individuals.Methods: This study was a randomized clinical trial. After a period of conventional physiotherapy and applying inclusion criteria, ۲۸ patients with ACL reconstruction surgery were randomly divided into two groups of cognitive dual-task and single-task balance exercises. Each group received the relevant exercises for four weeks, three times a week, with each session lasting ۲۰ min. Center of pressure variables, including mean displacement in anteriorposterior and medial-lateral directions, total path length, mean velocity of displacement, root mean square of displacement and velocity, and the elliptical area, were measured using the FDM pressure platform before and after the interventions as the primary outcomes. Knee Injury and Osteoarthritis Outcome Score (KOOS) scale was completed by the participants before and after the interventions.Results: The measured static balance variables and KOOS subscales had significant differences before and after intervention in both groups (P<۰.۰۵); however, no statistically significant difference was observed in these variables between the two groups. There was no significant correlation between KOOS subscales and measured static balance variables.Conclusion: Both cognitive dual-task and single-task balance exercises improved the indicators related to static balance and the level of functional disability of the knee. However, cognitive dual-task balance exercises had no superiority over single-task balance exercises in ACL-reconstructed individuals. Level of evidence: II

Anterior cruciate ligament reconstruction, Balance exercise, Cognitive dual-task, Static balance test