Predicting Lower Quarter Y-Balance Test Performance From Foot Characteristics

Abstract

Context: The lower quarter Y-Balance Test (YBT-LQ) is associated with injury risk; however, ankle range of motion impacts YBT-LQ. Arch height and foot sensation impact static balance, but these characteristics have not yet been evaluated relative to YBT-LQ. Objective: Determine if arch height index (AHI), forefoot sensation (SEN), and ankle dorsiflexion predict YBT-LQ composite score (CS). Design: Descriptive cohort. Setting: Athletic training laboratory. Participants: Twenty general population (14 females and 6 males; mean [SD]: age 35 [18] y, weight 70.02 [16.76] kg, height 1.68 [0.12] m) participated in this study. Interventions: AHI measurement system assessed arch height in 10% (AHI10) and 90% (AHI90) weight-bearing. Two-point discrim-a-gon discs assessed sensation (SEN) at the plantar great toe, third and fifth metatarsal heads. Biplane goniometer and weight-bearing lunge tests were used to measure static and weight-bearing dorsiflexion, respectively. The YBT-LQ assessed dynamic single-leg balance. Results: For right-limb dynamic single-leg balance, AHI90 and SEN were included in the final sequential prediction equation; however, neither model significantly (P = .052 and .074) predicted variance in YBT-LQ CS. For left-limb dynamic single-leg balance, both SEN and weight-bearing lunge test were included in the final sequential prediction equation. The regression model (SEN and weight-bearing lunge test) significantly (P = .047) predicted 22% of the variance in YBT-LQ CS. Conclusions: This study demonstrates that foot characteristics may play a role in YBT-LQ CS. The authors did not assess limb dominance in this study; therefore, the authors are unable to determine which limb would be the stance versus kicking limb. However, altered SEN and weight-bearing dorsiflexion appear to be contributing factors to YBT-LQ CS.