Effects of contact/collision sport history on gait in early-to mid-adulthood

Background:To determine the effect of contact/collision sport participation on measures of single-task(ST)and dual-task(DT)gait among early-to middle-aged adults.Methods:The study recruited 113 adults(34.88±11.80 years,(mean±SD);53.0%female)representing 4 groups.Groups included(a)former non-contact/collision athletes and non-athletes who are not physically active(n=28);(b)former non-contact/collision athletes who are physically active(n=29);(c)former contact/collision sport athletes who participated in high-risk sports and are physically active(n=29);and(d)former rugby players with prolonged repetitive head impact exposure history who are physically active(n=27).Gait parameters were collected using inertial measurement units during ST and DT gait.DT cost was calculated for all gait parameters(double support,gait speed,and stride length).Groups were compared first using one-way analysis of covariance.Then a multiple regression was performed for participants in the highrisk sport athletes and repetitive head impact exposure athletes groups only to predict gait outcomes from contact/collision sport career duration.Results:There were no significant differences between groups on any ST,DT,or DT cost outcomes(p>0.05).Contact/collision sport duration did not predict any ST,DT,or DT cost gait outcomes.Conclusion:Years and history of contact/collision sport participation does not appear to negatively affect or predict neurobehavioral function in early-to mid-adulthood among physically active individuals.

用姿势控制能力不足确定脑震荡遗留的神经功能缺损（英文）

Concussion,or mild traumatic brain injury,incidence rates have reached epidemic levels and impaired postural control is a cardinal symptom.The purpose of this review is to provide an overview of the linear and non-linear assessments of post-concussion postural control.The current acute evaluation for concussion utilizes the subjective balance error scoring system(BESS) to assess postural control.While the sensitivity of the overall test battery is high,the sensitivity of the BESS is unacceptably low and,with repeat administration,is unable to accurately identify recovery.Sophisticated measures of postural control,utilizing traditional linear assessments,have identified impairments in postural control well beyond BESS recovery.Both assessments of quiet stance and gait have identified lingering impairments for at least 1 month post-concussion.Recently,the application of non-linear metrics to concussion recovery have begun to receive limited attention with the most commonly utilized metric being approximate entropy(Ap En).Ap En,most commonly in the medial-lateral plane,has successfully identified impaired postural control in the acute post-concussion timeframe even when linear assessments of instrumented measures are equivalent to healthy pre-injury values;unfortunately these studies have not gone beyond the acute phase of recovery.One study has identified lingering deficits in postural control,utilizing Shannon and Renyi entropy metrics,which persist at least through clinical recovery and return to participation.Finally,limited evidence from two studies suggest that individuals with a previous history of a single concussion,even months or years prior,may display altered Ap En metrics.Overall,non-linear metrics provide a fertile area for future study to further the understanding of postural control impairments acutely post-concussion and address the current challenge of sensitive identification of recovery.