Balance control in youth hockey players with and without a history of concussions during a lower limb reaching task

Background: Sport-related concussion (SRC) is a functional injury that affects several clinical domains, including balance and cognition. The purpose of this study was, 1) to determine whether a lower limb visuomotor task could identify balance control differences between youth athletes with and without previous SRC; and 2) if balance is affected by training over time. Methods: Youth hockey players (n = 34) who reported previous SRC (CONCUSSED; n = 12; mean age = 14.4 yrs., SD = 1.6, mean time from injury = 1.9 yrs., median = 1.7 yrs. [0.6-4.6]) and no history of SRC (CONTROL; n = 22; mean age = 14.7, SD = 1.5) were tested twice over 70 days. Participants stood in single support on a Nintendo Wii Balance board sampled at 100 Hz and performed Go/No-Go tasks with each foot. Five FitLight Trainee (TM) (Aurora, ON) lights were arranged on the floor at 60 degrees, 30 degrees, and 0 degrees and illuminated in random GREEN (Go) or RED (No-Go). Balance was assessed using root mean square displacement and velocity of CoP in anterior-posterior and medial-lateral directions. Findings: CONCUSSED had significantly lower velocity of CoP in the anterior-posterior (F-(1,F- 32) = 13.81, p <.001) and medial-lateral (F-(1,F- 32) = 13.80, p <.001) directions than CONTROL, with no learning effects over time (anterior-posterior: F-(1,F- 32) = 0.30, p =.137: F-(1,F- 32) = 0.91, p =.346; medial-lateral: F-(1,F- 32) = 0.91, p =.346). These findings suggest that CONCUSSED consistently performed the task more conservatively. Interpretation: A lower limb Go/No-Go task may objectively identify differences between youth athletes with and without previous SRC. These visuomotor and balance control deficits may persist beyond clinical recovery.