Philippe Fait

Altered integrated locomotor and cognitive function in elite athletes 30 days postconcussion: a preliminary study.

Objective:To begin to understand changes in locomotor navigation in elite athletes following concussion. Methods:Clinical measures and gait analysis were undertaken on average 37.33 days (SD = 4.8) postconcussion for 6 athletes as well as for a control group of athletes matched for age, sex, and team. The locomotor task consisted of walking at a self-selected speed along an unobstructed or obstructed path with and without a visual interference task. The trends for 4 dependent variables were described (2 for gait behavior and 2 for cognitive behavior). A principal component analysis was used to reduce data to root sources of variance among these variables. General group differences were tested with Wilcoxon matched-pairs tests on factorial scores. Results:Athletes with concussion were symptom free at the time of testing and their neuropsychological test results were not different from those of athletes in the control group. However, when the laboratory data between paired groups were compared, descriptive analyses suggested potential group differences in navigating the obstacle. The simultaneous Stroop task appeared to present difficulty for both groups. A significant group effect was found on the component of the factorial analysis that was highly loaded with both gait and cognitive variables (minimum clearance, Stroop task errors, and cognitive dual-task costs), generally supporting the descriptive analyses by suggesting that athletes with concussion do not navigate the targeted complex environments like the control group. Conclusions:Athletes with concussion appear to still show navigational deficits in environments well after being considered fully recovered according to current return-to-play protocols. Although still preliminary and requiring further study, the present findings suggest that functional assessment within complex environment contexts could be considered before sending athletes back to play following a concussion, even in the absence of postconcussion symptoms or with normal clinical outcomes.

Alterations to locomotor navigation in a complex environment at 7 and 30 days following a concussion in an elite athlete

Primary objective: To compare the locomotor capacity during (1) unobstructed walking and (2) the circumvention of fixed obstacles with and without a simultaneous visual task in an elite athlete before and after a sports-related concussion. Research design: Case report. Methods and procedures: Gait analysis and clinical neuropsychological measures were taken pre- and at 7 and 30 days post-injury in an 18 year old male junior hockey player. The task consisted of walking along an unobstructed or obstructed path with or without a visual interference task. Measurements included dual tasks costs, response errors, maximal gait speed and minimal clearance with the obstacle. Main outcome and results: Although the athlete was symptom-free and neuropsychological test results returned to baseline relatively quickly, he showed continued errors in the interference task, abnormally small obstacle clearance distances and decreased maximal gait speed up to 30 days after the concussion. Conclusions: Concussion can result in persistent planning and attention deficits in ecologically valid, complex environments. This report suggests that functional assessment within an ecological context could be an innovative way to evaluate concussed athletes before sending them back to play, even in the absence of medically related symptoms or abnormal neuropsychological test results.

Modality-Specific, Multitask Locomotor Deficits Persist Despite Good Recovery After a Traumatic Brain Injury

OBJECTIVE To study the effects of sensory modality of simultaneous tasks during walking with and without obstacles after moderate to severe traumatic brain injury (TBI). DESIGN Group comparison study. SETTING Gait analysis laboratory within a postacute rehabilitation facility. PARTICIPANTS Volunteer sample (N=18). Persons with moderate to severe TBI (n=11) (9 men, 3 women; age, 37.56+/-13.79 y) and a comparison group (n=7) of subjects without neurologic problems matched on average for body mass index and age (4 men, 3 women; age, 39.19+/-17.35 y). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Magnitudes and variability for walking speeds, foot clearance margins (ratio of foot clearance distance to obstacle height), and response reaction times (both direct and as a relative cost because of obstacle avoidance). RESULTS The TBI group had well-recovered walking speeds and a general ability to avoid obstacles. However, these subjects did show lower trail limb toe clearances (P=.003) across all conditions. Response reaction times to the Stroop tasks were longer in general for the TBI group (P=.017), and this group showed significant increases in response reaction times for the visual modality within the more challenging obstacle avoidance task that was not observed for control subjects. A measure of multitask costs related to differences in response reaction times between obstructed and unobstructed trials also only showed increased attention costs for the visual over the auditory stimuli for the TBI group (P=.002). CONCLUSIONS Mobility is a complex construct, and the present results provide preliminary findings that, even after good locomotor recovery, subjects with moderate to severe TBI show residual locomotor deficits in multitasking. Furthermore, our results suggest that sensory modality is important, and greater multitask costs occur during sensory competition (ie, visual interference).

Imaging "brain strain" in youth athletes with mild traumatic brain injury during dual-task performance

Mild traumatic brain injury (mTBI) is a common cause of injury in youth athletes. Much of what is known about the sequelae of mTBI is yielded from the adult literature, and it appears that it is mainly those with persistent post-injury symptoms who have ongoing cognitive and neural abnormalities. However, most studies have employed single-task paradigms, which may not be challenging enough to uncover subtle deficits. We sought to examine the neural correlates of dual-task performance in male athletes aged 9-15 years using a functional neuroimaging protocol. Participants included 13 youths with a history of mTBI three to six months prior to testing and 14 typically-developing controls. All participants completed a working memory task in isolation (single-task) and while completing a concurrent motor task (dual-task); neural activity during performance was then compared between groups. Although working memory performance was similar during the single-task condition, increased working memory load resulted in an altered pattern of neural activation in key working memory areas (i.e., dorsolateral prefrontal and parietal cortices) in youth with mTBI relative to controls. During the dual-task condition, accuracy was similar between groups but injured youth performed slower than typically-developing controls, suggesting a speed-accuracy tradeoff in the mTBI group only. The injured youths also exhibited abnormal recruitment of brain structures involved in both working memory and dual-tasking. These data show that the dual-task paradigm can uncover functional impairments in youth with mTBI who are not highly symptomatic and who do not exhibit neuropsychological dysfunction. Moreover, neural recruitment abnormalities were noted in both task conditions, which we argue suggests mTBI-related disruptions in achieving efficient cognitive control and allocation of processing resources.

Increasing Task Complexity and ICE Hockey Skills of Youth Athletes

The objective of this pilot study was to investigate the effects on cognitive performance of progressively adding tasks specific to ice hockey (skating, stick handling, and obstacle avoidance) during a visual interference task (Stroop Color Word Test–interference condition). In addition, the effects on locomotor performance of progressively adding tasks of stickhandling, visual interference, and obstacle avoidance related to maximal skating speed and minimal obstacle clearance were investigated in eight male athletes ages 10 to 12 years. Results revealed decreased performance on both cognitive and physical measures with increased task complexity, suggesting that adding complexity to an environment influences hockey skill performance.

Management of persistent postconcussion symptoms in youth: a randomised control trial protocol

Introduction Current management of concussion consists of early education, rest until symptom free, with gradual return to school and physical activity protocols. Although this management strategy is effective for most youth who sustain a concussion, it is not an appropriate strategy for youth with persistent postconcussion symptoms. Prolonged rest and periods of restricted activity may place youth at risk for secondary issues and contribute to the chronicity of postconcussion symptoms. The purpose of this study is to evaluate the efficacy of an active rehabilitation protocol for youth who are slow to recover from concussion. It is hypothesised that an active rehabilitation intervention can reduce persistent postconcussion symptoms, improve function and facilitate return to activity. This article describes the research protocol. Methods and analysis This is a randomised clinical trial with blinded outcome measurement. Participants will be recruited and randomly assigned to 1 of 2 treatment groups, an active rehabilitation intervention or a standard care education group. Both groups will receive standard care education. However, the active rehabilitation group will participate in an additional low-intensity exercise programme consisting of aerobic, coordination and visualisation exercises. Both the active rehabilitation and the standard care education interventions will be 6 weeks in duration. The primary outcome measure is postconcussion symptoms. Secondary outcome measures include functional recovery (cognitive, motor, psychosocial and emotional functioning) and return to activity. Outcome measures will be administered preintervention and postintervention. The primary outcome measure will also be repeated 2 weeks into the intervention period. Ethics and dissemination This study has been approved by the Holland Bloorview Kids Rehabilitation Hospital research ethics board (REB # 13-459). The findings from this study will be shared with the general public, sport associations, relevant brain injury organisations and healthcare professionals. Trial registration number NCT02257749.

Efficiency of an Active Rehabilitation Intervention in a Slow-to-Recover Paediatric Population following Mild Traumatic Brain Injury: A Pilot Study

Objective. The aim of this study was to identify whether the addition of an individualised Active Rehabilitation Intervention to standard care influences recovery of young patients who are slow-to-recover following a mTBI. Methods. Fifteen participants aged 15 ± 2 years received standard care and an individualised Active Rehabilitation Intervention which included (1) low- to high-intensity aerobic training; (2) sport-specific coordination exercises; and (3) therapeutic balance exercises. The following criteria were used to measure the resolution of signs and symptoms of mTBI: (1) absence of postconcussion symptoms for more than 7 consecutive days; (2) cognitive function corresponding to normative data; and (3) absence of deficits in coordination and balance. Results. The Active Rehabilitation Intervention lasted 49 ± 17 days. The duration of the intervention was correlated with self-reported participation (x-=84.64±19.63%, r = −0.792, p < 0.001). The average postconcussion symptom inventory (PCSI) score went from a total of 36.85 ± 23.21 points to 4.31 ± 5.04 points after the intervention (Z = −3.18, p = 0.001). Conclusion. A progressive submaximal Active Rehabilitation Intervention may represent an important asset in the recovery of young patients who are slow-to-recover following a mTBI.

Cervical Spine Involvement in Mild Traumatic Brain Injury: A Review

Background. There is a lack of scientific evidence in the literature on the involvement of the cervical spine in mTBI; however, its involvement is clinically accepted. Objective. This paper reviews evidence for the involvement of the cervical spine in mTBI symptoms, the mechanisms of injury, and the efficacy of therapy for cervical spine with concussion-related symptoms. Methods. A keyword search was conducted on PubMed, ICL, SportDiscus, PEDro, CINAHL, and Cochrane Library databases for articles published since 1990. The reference lists of articles meeting the criteria (original data articles, literature reviews, and clinical guidelines) were also searched in the same databases. Results. 4,854 records were screened and 43 articles were retained. Those articles were used to describe different subjects such as mTBIs signs and symptoms, mechanisms of injury, and treatments of the cervical spine. Conclusions. The hypothesis of cervical spine involvement in post-mTBI symptoms and in PCS (postconcussion syndrome) is supported by increasing evidence and is widely accepted clinically. For the management and treatment of mTBIs, few articles were available in the literature, and relevant studies showed interesting results about manual therapy and exercises as efficient tools for health care practitioners.

Concussion and Concurrent Cognitive and Sport-specific Task Performance in Youth Ice Hockey Players: A Single-case Pilot Study

Background: Concussion is common in the sport of ice hockey and can cause deficits in cognitive function. In most situations, ice hockey participation requires the performance of more than one skill at a time. It has been reported that following concussion in athletes, performance deficits arise when locomotor and cognitive tasks are performed concurrently that may have otherwise gone unnoticed if assessed in isolation of one another. The purpose of this pilot study was to explore the effect of concussion on cognition during concurrent ice hockey specific tasks in youth ice hockey players. Methods: This single case pilot study compared the performance of 4 male youth ice hockey players who had experienced a concussion in the previous ice hockey season (mean age=11.7 ± 0.3 years; mean time since injury=92.5 ± 49.1 days) to a group of 10 non-injured controls (mean age=11.8 ± 0.8 years). Participants completed a randomized combination of three ice hockey specific tasks while concurrently completing a visual interference task (modified Stroop task). Results: Participants who experienced a concussion within the previous ice hockey season and were ≤ 58 days post-injury demonstrated significantly poorer cognitive performance (increased cognitive dual task cost) across all conditions when completing the visual interference task concurrently with ice hockey specific skills (p ≤ 0.05). Conclusion: This study acts as an initial step towards the development of a sport-specific assessment of functional performance following concussion in youth ice hockey players to help inform safer return to play.

Driving assessment and rehabilitation using a driving simulator in individuals with traumatic brain injury: A scoping review

BACKGROUND Due to the heterogeneity of the lesion following a traumatic brain injury (TBI) and the complexity of the driving task, driving assessment and rehabilitation in TBI individuals is challenging. Conventional driving assessment (on-road and in-clinic evaluations) has failed demonstrating effectiveness to assess fitness to drive in TBI individuals. OBJECTIVE We aimed to determine if driving simulators represent an interesting opportunity in assessing and rehabilitating driving skills in TBI individuals. METHODS We searched PubMed, CINAHL and Cochrane library databases between 27-02-2014 and 08-04-2014 for articles published since 2000 with the contents of simulator driving assessment and rehabilitation. RESULTS Out of 488, eight articles with the subject of simulator driving assessment and two with the subject of simulator driving rehabilitation in individuals with TBI were reviewed. CONCLUSIONS Driving simulators represent a promising avenue for the assessment and rehabilitation of driving skills in TBI individuals as it allows control of stimuli in a safe, challenging and ecologically valid environment and offer the opportunity to measure and record driving performance. Additional studies, however, are needed to document strengths and limitations of this method.