Minimal detectable change and reliability of the star excursion balance test in patients with lateral ankle sprain

Objective: Lateral ankle sprain (LAS) is one of the most prevalent musculoskeletal injuries in the general population and athletes. Dynamic postural control deficits and somatosensory alterations are common signs after an episode of LAS. It is important to detect these deficits to prevent a recurrent sprain and the development of chronic ankle instability. The Star Excursion Balance Test (SEBT) is a tool used to assess dynamic postural control in patients with LAS. SEBT test-retest reliability has been evaluated in several populations. However, no data on patients with LAS are available and we do not know the minimal detectable change (MDC). The primary objective of our study was to obtain the MDC for normalized reach distances of the eight SEBT directions in patients with LAS. The secondary objective was to determine test-retest reliability.

Methods: Cross-sectional study. Thirty-one patients (between 18 and 40 years old) diagnosed with a Grade I or II LAS. Participants were evaluated by two raters at two time-points separated by an interval of 24-72 hrs. In each assessment, four practice trials were allowed, then three test trials were performed in a randomized order. Normalized reaching distances were analyzed.

Results: From the initial 31 patients, two were eliminated, so 29 patients were considered for the final analysis. The MDC values obtained were 6.73-13.36%, and the medial and posteromedial directions showed the lowest and highest values, respectively. A statistically significant increase was found in lateral direction between T0 and T1. Intraclass correlation coefficients ranged from 0.72 to 0.93.

Conclusion: The SEBT is an accurate and reliable tool to assess dynamic postural control in patients with LAS.