Predicting dynamic balance improvements following 4-weeks of balance training in chronic ankle instability patients.

Objectives: Balance training typically features as a central component of exercise-based rehabilitation programs for patients with lateral ankle sprain and chronic ankle instability (CAI). The purpose of this study was to conduct a responder/non-responder analysis using existing data to identify factors associated with improvements in dynamic balance performance in CAI patients.

Design: Secondary data analysis.

Methods: Data was used from 73 CAI patients who participated in 6 previous investigations that used the same balance training program. We defined treatment success as a patient exceeding the minimal detectable change score (8.15%) for the posteriomedial direction of the Star Excursion Balance Test (SEBT-PM). Baseline measures of participant and injury demographics, patient-reported function, and dynamic balance were entered into a step-wise logistic regression model to determine the best set of predictors of treatment success.

Results: Only 28 out of 73 patients (38.4%) demonstrated a successful improvement in SEBT-PM reach after balance training. Of the variables assessed, SEBT-PM reach distance ≤85.18% and self-reported function activities of daily living score ≤92.55% were significant predictors of treatment success (p<0.001). If a patient met both these criteria there was a 70% probability of a successful treatment, indicating a 31.6% increase in the probability of a meaningful balance improvement after completing balance training.

Conclusions: Without screening, less than 40% of CAI patients experience a meaningful improvement in SEBT-PM following balance training. Completing a brief pre-treatment assessment of a patient- and clinician-oriented outcome can significantly improve the probability of determining patients with CAI who may improve dynamic balance after balance training.