Richelle M. Williams

Current and emerging rehabilitation for concussion: a review of the evidence.

Concussion is one of the most hotly debated topics in sports medicine today. Research surrounding concussion has experienced significant growth recently, especially in the areas of incidence, assessment, and recovery. However, there is limited research on the most effective rehabilitation approaches for this injury. This review evaluates the current literature for evidence for and against physical and cognitive rest and the emerging areas targeting vestibular, oculomotor, and pharmacologic interventions for the rehabilitation of sport-related concussion.

Athletic Trainers’ Management Practices and Referral Patterns for Adolescent Athletes After Sport-Related Concussion

Background: Athletic trainers (ATs) play an important role in the evaluation, management, and referral of student-athletes after sport-related concussion. Understanding factors that influence ATs’ patient care decisions is important to ensure best practices are followed. Purpose: To identify ATs’ current concussion management practices and referral patterns for adolescent student-athletes after sport-related concussion as well as the factors associated with those practices. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: A total of 851 participants from a convenience sample of 3286 ATs employed in the secondary school setting (25.9% response rate) completed the Athletic Trainers’ Beliefs, Attitudes, and Knowledge of Pediatric Athletes with Concussions (BAKPAC-AT) survey. The BAKPAC-AT consists of several questions to assess ATs’ concussion management, referral practices, and established relationships with other health care professionals. Results: The majority of ATs had a written concussion policy (82.4%, n = 701) and standing orders approved by their directing physician (67.3%, n = 573); 75.1% (n = 639) of ATs conduct baseline testing, with the majority using computerized neurocognitive tests (71.2%, n = 606). Follow-up concussion testing was employed by 81.8% (n = 696). Years of certification (P = 0.049) and type of secondary school (P = 0.033) predicted ATs’ use of baseline testing. Nearly half of the respondents (48.8%, n = 415) refer 100% of concussion cases to a physician. The most influential factors that lead to a referral were state law (40.3%, n = 343), personal preference (34.7%, n = 295), and school district policy (24.8%, n = 211). Conclusion: Of the ATs surveyed, most were engaged in baseline and follow-up testing, primarily with neurocognitive tests. Most ATs refer patients to physicians after concussion. While state regulation and personal preference were primary factors influencing referral decisions, it is unclear at what point of care the referral occurs.

Football players' head-impact exposure after limiting of full-contact practices

CONTEXT Sporting organizations limit full-contact football practices to reduce concussion risk and based on speculation that repeated head impacts may result in long-term neurodegeneration. OBJECTIVE To directly compare head-impact exposure in high school football players before and after a statewide restriction on full-contact practices. DESIGN Cross-sectional study. SETTING High school football field. PATIENTS OR OTHER PARTICIPANTS Participants were varsity football athletes from a single high school. Before the rule change, 26 athletes (age = 16.2 ± 0.8 years, height = 179.6 ± 6.4 cm, weight = 81.9 ± 13.1 kg) participated. After the rule change, 24 athletes (age = 15.9 ± 0.8 years, height = 178.3 ± 6.5 cm, weight = 76.2 ± 11.6 kg) participated. Nine athletes participated in both years of the investigation. MAIN OUTCOME MEASURE(S) Head-impact exposure was monitored using the Head Impact Telemetry System while the athletes participated in football games and practices in the seasons before and after the rule change. Head-impact frequency, location, and magnitude (ie, linear acceleration, rotational acceleration, and Head Impact Telemetry severity profile [HITsp], respectively) were measured. RESULTS A total of 15 398 impacts (592 impacts per player per season) were captured before the rule change and 8269 impacts (345 impacts per player per season) after the change. An average 42% decline in impact exposure occurred across all players, with practice-exposure declines occurring among linemen (46% decline); receivers, cornerbacks, and safeties (41% decline); and tight ends, running backs (including fullbacks), and linebackers (39% decline). Impact magnitudes remained largely unchanged between the years. CONCLUSIONS A rule change limiting full-contact high school football practices appears to have been effective in reducing head-impact exposure across all players, with the largest reduction occurring among linemen. This finding is likely associated with the rule modification, particularly because the coaching staff and offensive scheme remained consistent, yet how this reduction influences concussion risk and long-term cognitive health remains unknown.

Brain Network Activation Technology Does Not Assist with Concussion Diagnosis and Return to Play in Football Athletes

Background Concussion diagnosis and management remains a largely subjective process. This investigation sought to evaluate the utility of a novel neuroelectric measure for concussion diagnosis and return to play decision-making. Hypothesis Brain Network Activation (BNA) scores obtained within 72-h of injury will be lower than the athlete’s preseason evaluation and that of a matched control athlete; and the BNA will demonstrate ongoing declines at the return to play and post-season time points, while standard measures will have returned to pre-injury and control athlete levels. Design Case–control study. Methods Football athletes with a diagnosed concussion (n = 8) and matched control football athletes (n = 8) completed a preseason evaluation of cognitive (i.e., Cogstate Computerized Cognitive Assessment Tool) and neuroelectric function (i.e., BNA), clinical reaction time, SCAT3 self-reported symptoms, and quality of life (i.e., Health Behavior Inventory and Satisfaction with Life Scale). Following a diagnosed concussion, injured and control athletes completed post-injury evaluations within 72-h, once asymptomatic, and at the conclusion of the football season. Results Case analysis of the neuroelectric assessment failed to provide improved diagnostics beyond traditional clinical measures. Statistical analyses indicated significant BNA improvements in the concussed and control groups from baseline to the asymptomatic timepoint. Conclusion With additional attention being placed on rapid and accurate concussion diagnostics and return to play decision-making, the addition of a novel neuroelectric assessment does not appear to provide additional clinical benefit at this time. Clinicians should continue to follow the recommendations for the clinical management of concussion with the assessment of the symptom, cognitive, and motor control domains.

Head impact measurement devices: a clinical review

Context: Concussive injuries are at the forefront of sports medicine research. Recently, researchers have used a variety of head- and helmet-based impact-monitoring devices to quantify impacts sustained during contact sport participation. This review provides an up-to-date collection of head accelerometer use at the youth, high school, and collegiate levels. Evidence Acquisition: PubMed was searched for articles published between 1980 and 2015 using the terms accelerometer and concussion, impact sensor and concussion, head impact telemetry system, head impact telemetry, and linear acceleration and concussion. An additional Google search was performed to capture devices without publications. Study Design: Clinical review. Level of Evidence: Level 4. Results: Twenty-four products track and/or record head impact for clinical or research use. Ten of these head impact devices have publications supporting their utility. Conclusion: Head impact measuring devices can describe athlete exposure in terms of magnitude and/or frequency, highlighting their utility within a multimodal approach for concussion assessment and diagnosis.

Test-Retest Reliability and Practice Effects of the Stability Evaluation Test

CONTEXT Postural control plays an essential role in concussion evaluation. The Stability Evaluation Test (SET) aims to objectively analyze postural control by measuring sway velocity on the NeuroCom VSR portable force platform (Natus, San Carlos, CA). OBJECTIVE To assess the test-retest reliability and practice effects of the SET protocol. DESIGN Cohort. SETTING Research laboratory. PATIENTS OR OTHER PARTICIPANTS 50 healthy adults (20 men, 30 women, age 25.30 ± 3.60 y, height 166.60± 12.80 cm, mass 68.80 ± 13.90 kg). INTERVENTIONS All participants completed 4 trials of the SET. Each trial consisted of six 20-s balance tests with eyes closed, under the following conditions: double-leg firm (DFi), single-leg firm (SFi), tandem firm (TFi), double-leg foam (DFo), single-leg foam (SFo), and tandem foam (TFo). Each trial was separated by a 5-min seated rest period. MAIN OUTCOME MEASURES The dependent variable was sway velocity (deg/s), with lower values indicating better balance. Sway velocity was recorded for each of the 6 conditions as well as a composite score for each trial. Test-retest reliability was analyzed across 4 trials with intraclass correlation coefficients (ICCs). Practice effects analyzed with repeated measures analysis of variance, followed by Tukey post hoc comparisons for any significant main effects (P < .05). RESULTS Sway-velocity reliability values were good to excellent: DFi (ICC = .88; 95%CI: .81, .92), SFi (ICC = .75; 95%CI: .61, .85), TFi (ICC = .84; 95%CI: .75, .90), DFo (ICC = .83; 95%CI: .74, .90), SFo (ICC = .82; 95%CI: .72, .89), TFo (ICC = .81; 95%CI: .69, .88), and composite score (ICC = .93; 95%CI: .88, .95). Significant practice effects (P < .05) were noted on the SFi, DFo, SFo, TFo conditions and composite scores. CONCLUSIONS Our results suggest the SET has good to excellent reliability for the assessment of postural control in healthy adults. Due to the practice effects noted, a familiarization session is recommended (ie, all 6 conditions) before data are recorded. Future studies should evaluate injured patients to determine meaningful change scores during various injuries.

No Seasonal Changes in Cognitive Functioning Among High School Football Athletes: Implementation of a Novel Electrophysiological Measure and Standard Clinical Measures

Objective: To evaluate neuroelectric and cognitive function relative to a season of football participation. Cognitive and neuroelectric function declines are hypothesized to be present in football athletes. Design: Observational. Setting: Athletic fields and research laboratory. Patients (or Participants): Seventy-seven high school athletes (15.9 + 0.9 years, 178.6 + 7.2 cm, 74.4 + 14.7 kg, and 0.8 + 0.8 self-reported concussions) participating in football (n = 46) and noncontact sports (n = 31). Interventions (or Assessment of Risk Factors): All athletes completed preseason, midseason, and postseason assessments of cognitive and neuroelectric function, self-reported symptoms, and quality of life. All athletes participated in their respective sports without intervention, while head impact exposure in football athletes was tracked using the Head Impact Telemetry System. Main Outcome Measures: Cognitive performance was based on Cogstate computerized cognitive assessment tool processing speed, attention, learning, working memory speed, and working memory accuracy scores. ElMindA brain network activation amplitude, synchronization, timing and connectivity brain network activation scores demarcated neuroelectric performance. Quality of life was assessed on the Health Behavior Inventory and Satisfaction with Life Scale and symptoms on the SCAT3 inventory. Results: Football and control sport athletes did not show declines in cognitive or neuroelectric function, quality-of-life measures, or symptom reports across a season of sport participation. Conclusions: These findings refute the notion that routine football participation places athletes at risk for acute cognitive declines. The lack of impairment may be associated with no association with head impacts and cognitive function, increased physical activity offsetting any declines, and/or test sensitivity. How these findings are associated with long-term cognitive function is unknown.

Concussion knowledge, attitudes, and perceived level of involvement by american youth sport coaches in concussion management

Objective To describe concussion knowledge and attitudes of youth sport coaches and relationships among knowledge, attitudes, and perceptions of coach involvement in concussion management. Design Cross-sectional survey. Setting Youth sport coaches in North Carolina and Arizona. Subjects 81 youth sport coaches (males: n=69; females: n=11; age=42, IQR=33,45). Intervention A validated survey identifying demographics, concussion knowledge, attitudes, and beliefs. Outcome measures The primary outcome was perceived level of coach involvement in concussion management. Descriptive and univariable statistics were used to examine knowledge and attitude differences by demographic factors and perceived involvement. Multivariable logistic regression examined associations between knowledge and attitude and perceived level of coach involvement (lower agreement vs. higher agreement). Results Knowledge was low-moderate (Median=13/23, IQR=11,14.5), with 75% indicating a loss of consciousness always occurs with concussion. Attitudes were positive (Median=42/42, IQR=40,42). Forty-seven (58%) strongly agreed or agreed that coaches should be involved in clinical decision-making. There were no differences in knowledge or attitudes across gender, age, previous concussion education, or previous concussion history. Knowledge and attitude were not correlated (r=0.114; p=0.343). There were no knowledge (Median=13, IQR=12,15 vs. Median = 12, IQR=11,14) or attitude (Median=42, IQR=41,42 vs. Median = 42, IQR=39,42) differences between lower and higher perceived involvement, respectively. No associations were observed in the multivariable model with perceived coach involvement (p>0.05). Conclusions Coaches had limited knowledge, but expressed positive attitudes towards concussion. Educational efforts should target both knowledge and attitudes, as these constructs are not related, but are both key to improving the culture concerning concussion. Competing interests The project was funded in part by a grant from the National Operating Committee on Standards for Athletic Equipment.