Correlation Between The Y-balance Test, Weight-bearing Lunge Test, And Balance Error Scoring System Limb Symmetries

Abstract

Y-balance anterior reach (ANT) limb asymmetries have been associated with an increased risk of injury in athletes. It is unclear if limb asymmetry identified on the ANT are related to limb asymmetries in other common injury screening outcomes such as the Weight-Bearing Lunge Test (WBLT) or the Balance Error Scorings System (BESS). PURPOSE: To examine the correlation between Y-Balance ANT, WBLT, and BESS limb asymmetries. METHODS: Sixty-eight physically active adults (male=16; age=20.35±2.02yrs; height=166.31±32.58cm; weight=66.65±21.19kg) who were free from lower extremity injury and engaging in all desired physical activities participated. Subjects completed one data collection session in which all measures were collected on both limbs. The Y-Balance ANT involved subjects balancing on the stance limb while maximally reaching with the non-stance limb anteriorly. Four practice followed by three test trials were completed, normalized to leg length, and averaged for analysis (%). One trial of the WBLT was performed to assess maximal dorsiflexion (cm) using the knee to wall principle. One practice and one test trial of the eyes-closed BESS single-leg stance firm and foam conditions were completed. Errors were recorded during 20s trials. Asymmetry was calculated for ANT, WBLT, and BESS conditions by determining the absolute difference between scores for the left and right limbs. Separate Pearson correlations were completed to examine the relationship between ANT asymmetry and WBLT, BESS-Firm, and BESS-Foam asymmetry. Alpha-level was set a-priori at p≤0.05. RESULTS: There was a significant, weak correlation between ANT asymmetry (3.11±3.47%) and WBLT asymmetry (1.18±1.22cm, r=0.26, r2=0.07, p=0.04).There were no significant correlations between ANT asymmetry and BESS-Firm (1.68±1.60, r=-0.122, p=0.32) or BESS-Foam (1.47±1.31, r=-0.19, p=0.12) asymmetries. CONCLUSIONS: Y-Balance ANT asymmetry was weakly correlated with WBLT and BESS asymmetries. These findings indicate that WBLT and BESS asymmetries may provide unique injury risk information if used in conjunction with ANT asymmetry in prospective injury surveillance studies. Further research is needed to determine the predictive nature of WBLT and BESS asymmetries and how these measures may work in concert to predict injury risk.