The evaluation of between-limb synchrony and reactive balance control measures as diagnostic tools for concussion in young ice hockey players

Abstract

Problem This work explored the potential to detect changes in interlimb coordination following sport-related concussion (SRC) among young male hockey players. We hypothesized athletes who have sustained SRC over the season would show a reduced magnitude of between-limb CoP spatial symmetry and temporal synchrony, which will suggest greater instability post-concussion.

Methods A convenience sample of 104, 13–18-year-old top-level competitive male ice hockey players with 146.63±12.75 days between tests was used. Participants were grouped based on whether they sustained a SRC between the pre- and post-season data collection time points, with 12 sustaining a SRC. Participants performed one 60 second trial of quiet standing with eyes open on force platforms. Participants who sustained a SRC participated in post-season balance testing 77.25±27.94 days after time of injury. Participants were placed in the fatigued group if they had completed performance testing prior to the balance test. The ratio of left and right limb root-mean-square CoP displacements were calculated from the anteroposterior (AP) and mediolateral (ML) CoP time series, to assess spatial symmetry. The cross-correlation of right and left limb CoP time series was used to obtain between-limb temporal synchrony of CoP displacements in AP and ML directions. Frequency decomposition of the data was completed to parse out the proactive and reactive components of balance control. Separate analysis of covariance (p < 0.05) on post-season temporal synchrony and spatial symmetry measures were conducted where SRC, fatigue status, and age were the dependent variables, and pre-season measures were the covariate.

Results There were no statistically significant differences in post-season ML and AP temporal synchrony and spatial symmetry scores between the SRC, fatigue, or age groups. The same can be said for all analysis with the frequency decomposed measures.

Conclusions Deficits in temporal and spatial between-limb synchrony and symmetry was not detected long-term in young male ice hockey players who have sustained a SRC. As well, fatigue has little effect on these measures which has clinical relevance in when this test may be conducted. Further research is required to clarify whether deficits exist closer to time of injury, and when those deficits resolve.