Quantifying Balance Control in Concussed Varsity Athletes

Abstract

Previous research has demonstrated that even at return to play (RTP), there are continued balance control deficits in previously concussed athletes. However, these deficits were only distinguishable using higher order measures, which might have been missed using traditional measures (Powers et al., 2013). Higher-order analyses provide better insights into the neural control of balance. Sparato and colleagues (2013) quantified the number of lateral posture adjustments (PA) during a stepping task and found young adults tend to elicit one PA whereas older adults with history of falls tended to use two. PURPOSE: To determine whether a PA measure can distinguish control differences between groups of young adults during gait initiation (GI) task. HYPOTHESIS: During GI, concussed individuals will make more PA than non-athletes and baseline athletes, respectively. METHOD: Participants were all females (17-24 years) and included: varsity soccer players (N=28, baseline), non-athletes (N=6), and concussed soccer players during the symptomatic phase (N=3). Participants were asked to stand quietly on a Bertec force plate (FP) with their feet together and hands by their sides with their eyes open or closed for 45s. After 45s, an auditory cue sounded and participants initiated gait from the FP by taking two steps. Postural adjustments made during the gait initiation phase were calculated using the vertical force and counting the number of inflection points from the start of GI to when the participants were completely off the FP. Participants were taken from three groups: Baseline Female Laurier Varsity Soccer Players, Non-Athletes, and Concussed Varsity Athletes at the asymptomatic and RTP stage of recovery. RESULTS: During eyes open, non-athletes made more PA than the baseline athletes (p=.034) but concussed soccer players were not different from the baseline athletes (p=.13). With eyes closed, all participants produced similar number of PA. CONCLUSSION: These preliminary findings suggest that a PA measurement during GI can distinguish athletes from non-athletes and hopefully with more concussed athlete participants, may be able to distinguish between concussed and non-concussed athletes. If this is true, this would be an effective measure to not only determine if an athlete is concussed, but also to determine if the concussed athlete is ready to return to activity.