Biomechanical and Physiological Variables in Dynamic and Functional Balance Control during Single-Leg Loading in Individuals with Chronic Ankle Instability: A Scoping Review.

BACKGROUND: This scoping review summarizes the tasks and outcomes in dynamic and functional balance assessments of individuals with chronic ankle instability, focusing on the physiological and biomechanical characteristics. METHOD: A comprehensive literature search was conducted in PubMed, Scopus, Web of Science, and MEDLINE databases in September 2023 and revised in April 2024. Studies evaluating dynamic and functional balance in chronic ankle instability using clinical tests, as well as biomechanical and physiological outcomes, were included. RESULTS: Out of 536 publications, 31 met the screening criteria. A history of ankle sprain was the main focus of the inclusion criteria (28 articles, 90%). The star excursion balance test, emphasizing maximum reach distance, was the most common quantitative task (12 articles, 66%). Physiological data mainly came from electromyography studies (7 articles, 23%), while biomechanical variables were often assessed through center of pressure studies using force plates (17 articles, 55%). CONCLUSIONS: The preferred quantitative clinical assessment was the star excursion balance test, focusing on normalized reach outcomes. Qualitative functional balance assessments emphasize landing activities and center of pressure displacement. Electromyography is commonly used to analyze the tibialis anterior and peroneus longus muscles. However, there is a lack of qualitative data on dynamic balance control, including morphological characteristics and the center of mass adaptation.

The correlation of centre of mass evaluation utilising accelerometry-based measurement and the clinical dynamic balance test in professional football athletes with chronic ankle instability.

Background: Similar to a modified star excursion balance test, the Y-balance test is recommended for use in clinical settings to evaluate dynamic balance, particularly in athletes with chronic ankle instability. However, due to the testing errors, there are certain restrictions. As a result, the modification of the centre of mass tracking system was developed in order to aid in the detection of the ability to control the dynamic balance. Therefore, the purpose of this study was to correlate the usage of an accelerometer for the shifting of the centre of mass during a dynamic balance test with a Y-balance test reach distance score. Methodology: Forty professional football athletes with CAI participated in this study by performing the Y-balance test three times while wearing an accelerometer. The jerk, RMS sway amplitude, mean velocity from the time domain, and the normalised reach distance scores of the Y-balance test in the anterior, posteromedial, and posterolateral directions were all collected. Results: There was a strong positive correlation of jerk and RMS sway amplitude with the normalised reach distance scores in the posteromedial direction (r = 0.706 and 0.777, respectively), a moderate positive correlation of jerk and RMS sway amplitude with the normalised reach distance scores in the posterolateral direction (r = 0.609 and 0.606, respectively), a moderate positive correlation of jerk and RMS sway amplitude with the composite reach distance scores (r = 0.531 and 0.573, respectively) and significant differences in the posteromedial, posterolateral and overall directions (p-value < 0.001). Conclusion: These findings indicate that the area of the centre of mass shifting as represented by the accelerometer can disclose the body's ability to control the centre of mass over the base of support when the body is moving. Furthermore, in this study, the RMS sway variable in the posteromedial direction appears to be the most prominent.