Less Than Half of Patients Recover Within 2 Weeks of Injury After a Sports-Related Mild Traumatic Brain Injury: A 2-Year Prospective Study

Association Between Follow-Up Visit Timing After A Concussion and Subsequent Care Seeking in Children and Youth: A Population-Based Study in British Columbia

OBJECTIVE

To assess the relationship between follow-up visit timing and occurrence of the first subsequent health care seeking visit.

SETTING

The province of British Columbia, Canada.

PARTICIPANTS

A total of 21 029 children and youth who were diagnosed with an initial concussion from January 1, 2016, to December 31, 2017. These data were obtained from Population Data BC.

DESIGN

A retrospective, descriptive correlational study.

MAIN MEASURES

Follow-up timing was measured categorically as timely (4 weeks), delayed (1-3 months), or no follow-up; the occurrence of a subsequent health care visit beyond 3 months postinjury was measured up to 12 months at 3-month intervals (ie, 4-6, 7-9, and 10-12 months). These variables were measured using diagnostic codes for concussion, post-concussion syndrome, and the 17 concussion symptoms.

RESULTS

After controlling for sociodemographic characteristics, having a delayed follow-up, relative to timely follow-up, was associated with higher odds of a subsequent health care seeking visit at 4 to 6 months (odds ratio [OR] = 2.68; confidence interval [CI], 2.08-3.47), 7 to 9 months (OR = 1.71; CI, 1.21-2.40), and 10 to 12 months (OR = 1.67; CI, 1.13-2.48). In contrast to having a delayed follow-up, having no follow-up, relative to timely follow-up, was associated with not having a subsequent health care seeking visit at 4 to 6 months (OR = 0.57; CI, 0.48-0.67) and 7 to 9 months (OR = 0.79; CI, 0.66-0.96), respectively.

CONCLUSIONS

Follow-up visit timing after a concussion in children and youth is associated with subsequent health care seeking. Greater efforts are needed to investigate the importance of initial follow-up visit timing, as they may play an integral role in injury prevention and symptom management following injury.

Sex Differences in Response to Low- Versus High-Volume Aerobic Exercise for Sport-Related Concussion: A Pilot Randomized Controlled Trial

OBJECTIVE

To assess sex differences in behavior and motivation of adolescent athletes with sport-related concussion (SRC) versus controls during a 2-week individualized aerobic exercise intervention.

SETTING

Academic center research laboratory.

PARTICIPANTS

Participants were enrolled within 10 days of SRC (n = 32; 15.6 ± 1.4 years, 33% female, 6.18 ± 2.21 days from injury). Twenty-eight control participants (16.0 ± 1.6 years, 33% female) were recruited.

DESIGN

Randomized control trial with a 1:1 block randomization scheme stratified by participant sex.

MAIN MEASURES

Clinical recovery time as determined by the study physician, heart rate threshold (HRt) on the Buffalo Concussion Treadmill Test, adherence rates (calculated as exercise volume completed/exercise volume prescribed), and behavioral assessments including the perceived competence scale (PCS) and the treatment self-regulation questionnaire (TSRQ).

RESULTS

Females achieved higher initial HRts (P = .007), ie, the maximum HR during exercise testing. Males and females with a concussion showed minimal differences in motivation and perceived competence. Although it did not reach statistical significance (P = .058), females in the low-volume group appeared to recover faster than the high-volume group. This trend was not seen in males. Seven (88%) of exercise-intolerant females had to stop an exercise bout early on 1 or more days due to more-than-mild symptom exacerbation versus 3 (17%) of exercise-intolerant males (P = .002).

CONCLUSION

Females with a concussion prescribed a high volume of aerobic exercise treatment appeared to take longer to recover than females with a concussion who were prescribed a lower volume, which was not seen in males. Increased training heart rate prescriptions due to higher initial HRts and symptom exacerbation during at-home exercise may have affected female exercise behavior. Although aerobic exercise benefits SRC recovery, this study highlights the need for future research to optimize exercise treatment prescriptions for females after SRC.

MRI-T2 Relaxometry is Increased in Mild Traumatic Brain Injury: Indications of Acute Brain Abnormalities After Injury

Mild traumatic brain injury (mTBI) is a common condition, particularly pervasive in contact sports environments. A range of symptoms can accompany this type of injury and negatively impact people's lives. As mTBI diagnosis and recovery largely rely on subjective reports, more objective injury markers are needed. The current study compared structural brain MRI-T2 relaxometry between a group of 40 male athletes with mTBI within 14 days of injury and 40 age-matched male controls. Voxel-averaged T2 relaxometry within the gray matter was increased for the mTBI group compared to controls (p < 0.001), with statistically significant increased T2 relaxometry particularly in superior cortical regions. Our findings indicate subtle brain abnormalities can be identified in acute mTBI using MRI-T2 relaxometry. These brain abnormalities may reflect inflammation present in the brain and could constitute an objective injury marker to supplement current subjective methods that dominate clinical decisions regarding diagnosis and prognosis. Future research should validate this potential marker with other data types, such as blood biomarkers or histological samples.

Radiological Correlates of Head Injuries in School-Level Rugby Union: A 10-Year Retrospective Cross-Sectional Analysis

BACKGROUND

Sport-related concussion (SRC) in rugby union is common and carries a high injury burden, especially among children. Computed tomography (CT) imaging is commonly used to assess rugby-related head injuries, including SRC, subjecting children to ionising radiation. In addition, there is concern about the relationship between SRC, repetitive head impacts and neurodegeneration.

OBJECTIVE

To review and correlate the imaging findings of head injuries in school-level rugby players from a public tertiary referral centre and a private multi-centre radiology service.

DESIGN

Descriptive, retrospective cross-sectional correlational study for the 2014-2023 period.

METHODS

Anonymised data were collected from the radiological information systems of a tertiary referral centre and a private radiology provider. Data included participant age, imaging modality, study type, date, findings and SRC status. The public and private datasets were analysed using descriptive and comparative statistics.

RESULTS

A total of 369 cases were identified (public n = 132, 36%). Mean participant age was 15 (± 2.5) years, with 78% (n = 289) clinically deemed to have an SRC. CT was performed in 347 (94%) cases, with abnormal findings reported in 50 studies (public n = 32). The most common findings were craniofacial fractures (n = 28) and intracranial injuries (n = 19). The sensitivity of CT for detecting SRC was 14%. Public sector participants were more likely to have an SRC (odds ratio: 8.39; 95% CI 8.37-8.41, p < 0.001).

CONCLUSIONS

CT demonstrates limited utility in the context of SRC beyond detecting craniofacial fractures or surgical emergencies, reinforcing clinical assessment as the diagnostic cornerstone. Protocol optimisation should prioritise radiation risk mitigation through strict adherence to paediatric low-dose guidelines.

Long-Term Brain Health Outcomes in Females With a History of Contact Sports: A Cross-Sectional Survey Analysis

OBJECTIVE

To assess whether female sex is associated with higher lifetime concussion risk and if years of contact sport participation and/or concussion history are associated with negative long-term cognitive and psychiatric difficulties in females compared with males.

DESIGN

Cross-sectional survey.

SETTING

ResearchMatch, a national health-based volunteer registry.

PARTICIPANTS

A total of 330 participants (111 females) with contact sport exposure.

INTERVENTIONS

Participants reported lifetime concussion history, age of first exposure, and duration of contact sport exposure.

MAIN OUTCOME MEASURES

Lifetime concussion history, depressive symptoms (PHQ-9), anxiety symptoms (GAD-7), and cognitive symptoms (BC-CCI).

RESULTS

Of 330 participants (N = 111 females), 57.1% of females reported at least one concussion. Females had fewer years of contact sport exposure than males (6.0 ± 4.5 vs 8.5 ± 8.9 years; P < 0.001). Age of first exposure was similar between sexes (females: 11.7 ± 8.9 years; males: 11.5 ± 5.3 years; P = 0.779). Female sex was not associated with a positive lifetime concussion history (OR = 1.13; 95% CI, 0.66-1.93; P = 0.662). Total years of contact sport exposure did not predict lifetime concussion history in females (OR = 1.02; 95% CI, 0.94-1.11; P = 0.667) but did in males (OR = 1.05; 95% CI, 1.01-1.10; P = 0.020). Increased lifetime concussions predicted increased late-life depressive, anxiety, and cognitive symptoms in both sexes.

CONCLUSIONS

Female sex was not associated with a higher likelihood of having a lifetime concussion history. Total years of contact sport exposure did not predict lifetime concussion risk in females but did in males. Increased lifetime concussions were associated with higher late-life depressive, anxiety, and cognitive symptoms in both sexes.

CLINICAL RELEVANCE

These findings highlight the importance of considering sex-specific differences in assessing long-term cognitive and psychiatric risks in former athletes.

Differences between the sexes in concussion knowledge and attitudes in community football (soccer) players in New Zealand

OBJECTIVES

To evaluate self-reported concussion knowledge and attitudes in community football players in New Zealand, comparisons were made between the sexes and those with and without history of concussion.

DESIGN

Cross-sectional cohort study.

METHODS

The Rosenbaum Concussion Knowledge and Attitudes Survey (RoCKAS) was used for data collection and analysis. Players were recruited through the New Zealand Football registered player database.

RESULTS

Seventy-four players had data eligible for inclusion (55 % female). Thirty-four players (45 %) had previously diagnosed concussion (56 % female). Mean Concussion Knowledge Index (CKI) scores were significantly (p = 0.002) higher for male (20.8 ± 1.4) than female (19 ± 3.7) players. There were no significant sex differences in mean Concussion Attitude Index (CAI) scores (female 63.7 ± 11.4, male 65.6 ± 6.0; p = 0.427). Surprisingly, 32 % female and 39 % male players indicated that they would play on with symptoms of concussion. Comparison within female players showed a significantly higher CKI (20.3 ± 1.7 versus 18.8 ± 2.6; p = 0.025) and higher CAI (66.5 ± 4.9 versus 64.1 ± 5.9; p = 0.151) in players with a history of concussion. There were no within male player trends for CKI or CAI.

CONCLUSIONS

Male players had a notably higher concussion knowledge (CKI) than female players. Females with a previously diagnosed concussion also had a notably higher CKI than female players with no concussion history. Therefore, healthcare professionals could play a key education role when managing players with concussion. Given over a third of players indicated that they would play on with symptoms of concussion, education should focus on short- and long-term impacts of concussion and potential consequences of concussion.

Association of early versus late care seeking for sport-related concussion in adolescent athletes in Canada: a historical cohort study

Objectives

This study aims to examine the association of time to recovery between early versus late presentation to outpatient community-based concussion management clinics following sport-related concussion (SRC) among adolescent Canadian athletes.

Methods

Using electronic health records (between January 2017 and December 2019) from the Complete Concussion Management Inc (CCMI) database, this was a historical cohort study of Canadian athletes aged 12-18 presenting for care early (0-7 days) or late (8-28 days) after SRC. Time-to-recovery was defined as the date of clinician clearance to return to sport. Propensity scores were first derived from logistic regression with early versus late clinical presentation as the outcome. Cox proportional hazards regression analysis was then used to model the relationship between early versus late clinical presentation and time to recovery, while including the propensity score to adjust for confounding. The association was expressed using hazard rate ratios (HRR) with 95% CIs.

Results

A total of 4696 patient records (mean age of 14.71 (±1.69 SD); 57.7% male) were eligible. Early presentation to a concussion management clinic following SRC was associated with faster time to recovery (adjusted HRR 1.23; 95% CI 1.14 to 1.32, p<0.001). This association was consistent within each quintile of the propensity score. The median time to recovery was 18 versus 22 days in the early and late groups, respectively.

Conclusion

Adolescent athletes with SRC have favourable recovery trajectories when presenting for care up to 28 days. Time to recovery (clinician clearance to return to sport) may be quicker with an earlier presentation which can lead to a faster return to sport.

Quality of Life in Adolescent Athletes With Sport-Related Concussion Prescribed Heart Rate-Targeted Aerobic Exercise Within 10 Days of Injury

Individualized aerobic exercise treatment prescribed within 10 days of injury facilitates recovery in adolescents after sport-related concussion (SRC) and reduces incidence of persisting post-concussive symptoms (PPCSs) beyond 4 weeks. The effect of aerobic exercise treatment on quality of life symptoms is, however, unknown. This planned secondary aim of a published randomized controlled trial found that while adolescents prescribed aerobic exercise recovered faster, there was no difference on the Pediatric Quality of Life (PedsQL) questionnaire scores during the 4-week intervention period. Nevertheless, adolescents who experienced PPCS reported significantly worse initial visit (within 10 days of injury) symptoms on the PedsQL than those who recovered within 4 weeks. Higher scores on the PedsQL correlated with greater initial visit concussion symptom burden and more abnormalities on a concussion-relevant visio-vestibular examination. Thus, the PedsQL captures the clinical severity of concussion and is prognostic of risk for delayed recovery when administered early after SRC in adolescents.

'Their role has a lot of purpose beyond being just being about exercises': a qualitative study of patients' experiences of physiotherapy following a mild traumatic brain injury

Following a mild traumatic brain injury (mTBI; also known as concussion), physiotherapists may be involved in injury identification, assessment and rehabilitation. However, how people perceive and experience the physiotherapist's role is not well understood. Semistructured interviews were undertaken with patients who saw a physiotherapist individually or as part of a multidisciplinary team following mTBI in New Zealand. Interviews were recorded, transcribed verbatim and analysed using the interpretive descriptive approach. A total of 12 interviews were held with participants aged 19-67 (50% female; mean age 37 (SD=14.8) years) who had a mTBI on average 9 (SD=8) months ago. Thematic coding of interviews generated four themes, each supported by three to five categories representing their experiences: (1) 'How physiotherapy could help me'-representing how the interventions were delivered; (2) 'Empower me to manage my mTBI'-representing participants learnings to self-manage; (3) 'Set me up to get the most out of treatment'-representing considerations needed before, during and after practice to maximise engagement and (4) 'Get to know me and what's important to me'-representing the importance of considering the person as a whole, and preferences for assessment, intervention, communication and culture throughout service delivery. Overall, participants reported variable mTBI care experiences yet perceived the physiotherapist as having a key role in supporting self-management and treating headaches, neck pain and balance issues. mTBI physiotherapy care needs to be more attuned to patients' preferences and circumstances and delivered in a way that maximises rehabilitation outcomes. Building effective therapeutic connections with patients may be key to addressing these concerns simultaneously in practice.

Individual-level analysis of MRI T2 relaxometry in mild traumatic brain injury: Possible indications of brain inflammation

Mild traumatic brain injury (mTBI), often called concussion, is a prevalent condition that can have significant implications for people's health, functioning and well-being. Current clinical practice relies on self-reported symptoms to guide decision-making regarding return to sport, employment, and education. Unfortunately, reliance on subjective evaluations may fail to accurately reflect the resolution of neuropathology, exposing individuals with mTBI to an increased risk of further head trauma. No objective technique currently exists to assess the microstructural alterations to brain tissue which characterise mTBI. MRI-based T2 relaxation is a quantitative imaging technique that is susceptible to detecting fluid properties in the brain and is hypothesised to indicate neuroinflammation. This study aimed to investigate the potential of individual-level T2 relaxometry to evaluate cellular damage from mTBI. 20 male participants with acute sports-related mTBI (within 14 days post-injury) and 44 healthy controls were recruited for this study. Each mTBI participant's voxel-wise T2 relaxometry map was analysed against healthy control averages using a voxel-wise z-test with false discovery rate correction. Five participants were re-scanned after clinical recovery and results were compared to their acute T2 relaxometry maps to assess reduction in potential neuroinflammation. T2 relaxation times were significantly increased in 19/20 (95 %) mTBI participants compared to healthy controls, in regions including the hippocampus, frontal cortex, parietal cortex, insula, cingulate cortex and cerebellum. Results suggest the presence of increased cerebral fluid in individuals with mTBI. Longitudinal results indicated a reduction in T2 relaxation for all five participants, indicating a possible resolution over time. This research highlights the potential of individual-level T2 relaxometry MRI as a non-invasive method for assessing subtle brain pathology in mTBI. Identifying and monitoring changes in the fluid content in the brain could aid in predicting recovery and developing individualised treatment plans for individuals with mTBI. Future research should validate this measure with other markers of inflammation (e.g. from blood biomarkers) to test whether T2-relaxometry is related to subtle brain inflammation in mTBI. In addition, future research should utilise larger control groups to establish normative ranges and compute robust z-score analyses.

Relationships between vestibular issues, noise sensitivity, anxiety and prolonged recovery from mild traumatic brain injury among adults: a scoping review

BACKGROUND

We investigated the extent of literature and findings on relationships between vestibular issues, noise sensitivity (NS), and anxiety. We were interested in how relationships among these factors impacted adults' recovery three months or more after mild traumatic brain injury (mTBI).

METHODS

We conducted a scoping review to evaluate the extent of evidence linking relationships between vestibular issues, NS and anxiety with recovery after mTBI. Data relating to study characteristics and key findings were extracted and used to inform a critical narrative synthesis of findings.

RESULTS

After screening and full-text review, we included two studies. Both studies considered the combination of vestibular issues, NS and anxiety and mTBI recovery. Vestibular issues, NS and anxiety were all significantly associated with one another and their presence was the strongest indicator that symptoms would extend beyond three-months after mTBI.

CONCLUSION

Few studies have focused on the relationships that vestibular issues, NS and anxiety have with one another and recovery after mTBI. Given the apparent strong relationships between these factors and prolonged recovery, we highlight this as an area warranting further investigation.

Use of the concussion check protocol for concussion assessment in a female soccer team over two consecutive seasons in New Zealand

AIM

Address deficiencies in access to sports sideline medical care by using a Concussion Check Protocol (CCP) for non-medically-trained people.

METHOD

A prospective observational cohort study was undertaken on a single amateur female club-based soccer team over two consecutive years in New Zealand utilising a non-medically trained support person termed a Safety officer. CCP is an extension of the King-Devick test with features such as warning signs and symptoms of concussion built into the application. All players suspected of having a potential concussive injury were tested on the match sideline.

RESULTS

The study overall incidence of match-related concussions was 20.8 (95% CI: 11.8 to 36.6) per 1000 match-hrs, with mean missed-match duration of 31 (95% CI: 27.9 to 34.1) days. Twelve players over the study had a significantly slower post-injury KD (49.9 [44.3 to 64.1]s; χ2(1) = 11.0; p = 0.0009; z = -2.9; p = 0.0033; d = 0.30) and/or reported symptoms, compared with their own baseline (47.2 [44.3 to 64.1]s). CCP had an overall sensitivity of 100% (95% CI: 73.5% to 100.0%), specificity of 100% (95% CI: 69.2% to 100.0%) and positive predictive value (PPV) of 100% (84.6% to 100.0%).

CONCLUSION

Sideline use of CCP was undertaken successfully by non-medically trained people and provided a reliable platform for concussion identification.

Female RNA concussion (FeRNAC) study: assessing hormone profiles and salivary RNA in females with concussion by emergency departments in New Zealand: a study protocol

BACKGROUND

Females of reproductive age with concussion report a greater number of symptoms that can be more severe and continue for longer than age matched males. Underlying mechanisms for sex differences are not well understood. Short non-coding Ribonucleic Acids (sncRNAs) are candidate salivary biomarkers for concussion and have been studied primarily in male athletes. Female sex hormones influence expression of these biomarkers, and it remains unclear whether a similar pattern of sncRNA expression would be observed in females following concussion. This study aims to evaluate recovery time, the ratio of salivary sncRNAs and symptom severity across different hormone profiles in females presenting to emergency departments (ED) with concussion and, to investigate the presence of low energy availability (LEA) as a potential modifier of concussion symptoms.

METHODS

This prospective cohort study recruits participants from New Zealand EDs who are biologically female, of reproductive age (16-50 years) and with a confirmed diagnosis of concussion from an ED healthcare professional. Participants are excluded by ED healthcare professionals from study recruitment as part of initial routine assessment if they have a pre-diagnosed psychiatric condition, neurological condition (i.e., epilepsy, cerebral palsy) or more than three previously diagnosed concussions. Participants provide a saliva sample for measurement of sncRNA's, and online survey responses relating to hormone profile and symptom recovery at 7-day intervals after injury until they report a full return to work/study. The study is being performed in accordance with ethical standards of the Declaration of Helsinki with ethics approval obtained from the Health and Disability Ethics Committee (HDEC #2021 EXP 11655), Auckland University of Technology Ethics Committee (AUTEC #22/110) and locality consent through Wellington hospital research office.

DISCUSSION

If saliva samples confirm presence of sncRNAs in females with concussion, it will provide evidence of the potential of saliva sampling as an objective tool to aid in diagnosis of, and confirmation of recovery from, concussion. Findings will determine whether expression of sncRNAs is influenced by steroid hormones in females and may outline the need for sex specific application and interpretation of sncRNAs as a clinical and/or research tool.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR) registration number ACTRN12623001129673.

Athletic Fear Avoidance in Athletes Receiving Rehabilitation for Sport-Related Concussion: A Preliminary Study

BACKGROUND

Fear avoidance after musculoskeletal injury is avoiding activity due to fear of pain and contributes to persistent symptoms, depression, and disability. Little is known about fear avoidance for sport (athletic fear avoidance) in athletes with sport-related concussion (SRC).

HYPOTHESIS

Athletic fear avoidance after SRC would be elevated at the start of rehabilitation, improve over time, and be associated with postconcussion recovery outcomes.

STUDY DESIGN

Observational study.

LEVEL OF EVIDENCE

Level 4.

METHODS

Athletes in rehabilitation after SRC participated. Testing at initial and discharge visits and 6-month follow-up included Athletic Fear Avoidance Questionnaire (AFAQ), Postconcussion Symptom Scale (PCSS), Profile of Mood States (POMS), and Dizziness Handicap Inventory (DHI). Differences were explored in AFAQ score at initial testing based on sex or age (<18 or ≥18 years). Change in questionnaire scores over time was examined. Association of AFAQ score with other questionnaire scores was determined at each timepoint.

RESULTS

A total of 48 athletes participated: 28 completed initial testing only (INITIAL ONLY), and 20 completed all testing (LONGITUDINAL). Across cohorts, the mean (SD) AFAQ score at initial testing was 24.3 (7.6) points, with no significant difference by sex or age. AFAQ, PCSS, POMS, and DHI scores improved in LONGITUDINAL; the effect size was large from initial to discharge testing (1.0, 1.0, 1.0, and 1.2, respectively) and variable from discharge to follow-up testing (0.52, -0.34, -0.08, and 0.02, respectively). AFAQ scores increased from discharge to follow-up in 3 athletes and were consistently above the mean value in 2 athletes. AFAQ score was significantly correlated to the other questionnaire scores at each timepoint (range, r = 0.36-0.75).

CONCLUSION

Athletic fear avoidance was elevated at the start of SRC rehabilitation, improved over time in most patients, and was associated with postconcussion symptoms, mood, and disability.

CLINICAL RELEVANCE

Athletic fear avoidance may impact recovery after SRC.

Can the Buffalo Concussion Treadmill Test Be Used as a Prognostic Indicator for Patients With Sport-Related Mild Traumatic Brain Injury?

OBJECTIVE

To establish whether time to exercise cessation using the Buffalo Concussion Treadmill Test (BCTT) protocol can be used as a prognostic indicator of recovery after sport-related mild traumatic brain injury (SR-mTBI).

DESIGN

Retrospective analysis of prospectively collected data.

SETTING

Specialist Concussion Clinic.

PARTICIPANTS

Three hundred and twenty one patients presenting between 2017 and 2019 who underwent BCTT for SR-mTBI.

INTERVENTIONS

Participants who remained symptomatic at a 2-week follow-up appointment after SR-mTBI underwent BCTT to develop a progressive subsymptom threshold exercise program with fortnightly follow-up until clinical recovery.

MAIN OUTCOME MEASURES

Clinical recovery was the primary outcome measure.

RESULTS

A total of 321 participants were eligible to participate in this study (mean age 22.94% and 46% female). The BCTT test duration was divided into 4-minute intervals and those who completed full 20 minutes. There was higher probability of clinical recovery in those who finished the entire 20-minute BCTT protocol compared with those who managed 17-<20 minutes (Hazard Ratio, HR 0.57), 13 to 16 minutes (HR 0.53), 9 to 12 minutes (HR 0.6), 5 to 8 minutes (HR 0.4), and 1 to 4 minutes (HR 0.7), respectively. Those seen earlier after injury ( P = 0.009), male patients ( P = 0.116), younger patients ( P = 0.0003), and those with physiological or cervical dominant ( P = 0.416) symptom clusters were more likely to achieve clinical recovery. Fifty percent of those who completed the full BCTT protocol achieved clinical recovery at day 19 post-injury.

CONCLUSIONS

The group completing full 20 minutes of BCTT achieved clinical recovery more quickly than those who did not complete full BCTT.

Acute Sport-Related Concussion Management and Return to Sport Time in High School Athletes

BACKGROUND

The current evidence for acute management practices of sport-related concussion (SRC) is often limited to in-clinic visits, with limited studies identifying professionals in early SRC care and the association with prolonged recovery outcomes.

PURPOSE

To describe acute SRC management practices (ie, the personnel in the initial evaluations, removal from activity) and test the association with prolonged return to sport (RTS) time.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

We conducted a retrospective cohort study of 17,081 high school SRCs accrued between the 2015-2016 and 2020-2021 academic years. We reported acute management practices and RTS time as frequencies stratified by sex, sport, and event type and compared athletic trainer (AT) access in initial evaluation with chi-square tests (P < .05). Separate logistic regressions estimated odds ratios (ORs) and 95% CIs for removal from activity and prolonged RTS >21 days by acute management practices.

RESULTS

Most SRCs (n = 12,311 [72.1%]) had complete initial evaluation by an AT. Boys had an AT evaluation in 75.5% (n = 2860/3787) of practice-related and 74.8% (n = 5551/7423) of competition-related events. Girls had an AT evaluation in 61.3% (n = 1294/2110) of practice-related and 69.3% (n = 2606/3761) of competition-related events. In sex-comparable sports (n = 6501), there was no difference between boys (n = 1654/2455 [67.4%]) and girls (n = 2779/4046 [68.7%]) having an AT involved in the first evaluation (χ2 = 1.21; P = .27). Notably, 25.3% of girls' SRCs were evaluated by a coach alone, and we observed differences in personnel in initial evaluations by sport. The odds of immediate removal were higher when an AT made the initial evaluation (OR, 2.8 [95% CI, 2.54-3.08]). The odds of prolonged RTS >21 days was lower for those with an AT in the initial evaluation (OR, 0.74 [95% CI, 0.65-0.84]) adjusting for significant factors from univariate analyses, boys relative to girls (OR, 0.85 [95% CI, 0.76-0.96]), specialty care relative to PCP (OR, 2.16 [95% CI, 1.90-2.46]), specialty care relative to urgent or ready care (OR, 0.99 [95% CI, 0.82-1.22]) concussion history (OR, 1.41 [95% CI, 1.22-1.63]), and removal from activity (OR, 0.90 [95% CI, 0.78-1.05]).

CONCLUSION

This study found variability in personnel involved in initial SRC evaluations, with higher percentages of athletes with SRCs having ATs make the initial evaluation during competitive events. There was no association between sex and AT involvement in comparable sports. There was an association between prolonged RTS and AT involvement, sex, concussion history, and location of follow-up care.

Describing the patient journey through healthcare pathways following mild traumatic brain injury in New Zealand using novel Graph analysis

AIM

To identify treatment provider sequences and healthcare pathway characteristics and outcomes for people with mild traumatic brain injury (mTBI) in New Zealand.

METHODS

Total mTBI costs and key pathway characteristics were analysed using national healthcare data (patient's injury and services provided). Graph analysis produced sequences of treatment provider types for claims with more than one appointment and healthcare outcomes (costs and time to exit pathway) were compared. Key pathway characteristics' effect on healthcare outcomes were evaluated.

RESULTS

In two years, 55,494 accepted mTBI claims cost ACC USD$93,647,261 over four years. For claims with more than one appointment (36%), healthcare pathways had a median 49 days (IQR, 12-185). The 89 treatment provider types resulted in 3,396 different provider sequences of which 25% were General Practitioners only (GP), 13% Emergency Department to GP (ED-GP) and 5% GP to Concussion Service (GP-CS). Pathways with shorter time to exit and lower costs had correct mTBI diagnosis at initial appointment. Income maintenance comprised 52% of costs but only occurred for 20% claims.

CONCLUSIONS

Improving healthcare pathways for people with mTBI by investing in training of providers to enable correct mTBI diagnosis could yield longer term cost savings. Interventions to reduce income maintenance costs are recommended.

Management of sports-related concussion in the emergency department

Sports-related concussion is a common presentation to the emergency department, with increasing evidence of short and long-term morbidity. The heterogeneity of symptoms and clinical outcomes, alongside a lack of familiarity with current guidance, can present significant challenges to clinicians. This article presents an overview of the current literature concerning assessment and management of sports-related concussion in the emergency department and outlines a framework for graduated return to activity as based upon the current national guidance.

A Potential Role Exists for Nutritional Interventions in the Chronic Phase of Mild Traumatic Brain Injury, Concussion and Sports-Related Concussion: A Systematic Review

Mild traumatic brain injury (mTBI) represents a significant burden for individuals, economies, and healthcare systems worldwide. Recovery protocols focus on medication and physiotherapy-based interventions. Animal studies have shown that antioxidants, branched-chain amino acids and omega-3 fatty acids may improve neurophysiological outcomes after TBI. However, there appears to be a paucity of nutritional interventions in humans with chronic (≥1 month) symptomology post-mTBI. This systematic literature review aimed to consolidate evidence for nutrition and dietary-related interventions in humans with chronic mTBI. The review was registered with the International Prospective Register of Systematic Reviews (PROSPERO; CRD42021277780) and conducted following the Preferred Reporting for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three reviewers searched five databases (PubMed/MEDLINE, Web of Science, SPORTDiscus, CINAHL Complete and Cochrane), which yielded 6164 studies. Nine studies met the inclusion criteria. The main finding was the lack of interventions conducted to date, and a quality assessment of the included studies was found to be fair to good. Due to heterogeneity, a meta-analysis was not feasible. The six nutrition areas identified (omega-3 fatty acids, melatonin, Enzogenol®, MLC901, ketogenic diet and phytocannabinoids) were safe and well-tolerated. It was found that these nutritional interventions may improve cognitive failures, sleep disturbances, anxiety, physical disability, systolic blood pressure volume and sport concussion assessment tool scores following mTBI. Potential areas of improvement identified for future studies included blinding, reporting compliance, and controlling for confounders. In conclusion, further research of higher quality is needed to investigate the role of nutrition in recovery from mTBI to reduce the burden of chronic outcomes following mTBI.

Clinical recovery from concussion-return to school and sport: a systematic review and meta-analysis

OBJECTIVE

To define the time frames, measures used and modifying factors influencing recovery, return to school/learn (RTL) and return to sport (RTS) after sport-related concussion (SRC).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

8 databases searched through 22 March 2022.

ELIGIBILITY CRITERIA

Studies with diagnosed/suspected SRC and interventions facilitating RTL/RTS or investigating the time and modifying factors for clinical recovery. Outcomes included days until symptom free, days until RTL and days until RTS. We documented study design, population, methodology and results. Risk of bias was evaluated using a modified Scottish Intercollegiate Guidelines Network tool.

RESULTS

278 studies were included (80.6% cohort studies and 92.8% from North America). 7.9% were considered high-quality studies, while 23.0% were considered high risk of bias and inadmissible. The mean days until symptom free was 14.0 days (95% CI: 12.7, 15.4; I²=98.0%). The mean days until RTL was 8.3 (95% CI: 5.6, 11.1; I²=99.3%), with 93% of athletes having a full RTL by 10 days without new academic support. The mean days until RTS was 19.8 days (95% CI: 18.8, 20.7; I²=99.3%), with high heterogeneity between studies. Several measures define and track recovery, with initial symptom burden remaining the strongest predictor of longer days until RTS. Continuing to play and delayed access to healthcare providers were associated with longer recovery. Premorbid and postmorbid factors (eg, depression/anxiety, migraine history) may modify recovery time frames. Though point estimates suggest that female sex or younger age cohorts take longer to recover, the heterogeneity of study designs, outcomes and overlap in CIs with male sex or older age cohorts suggests that all have similar recovery patterns.

CONCLUSION

Most athletes have full RTL by 10 days but take twice as long for an RTS.

PROSPERO REGISTRATION NUMBER

CRD42020159928.

When should an athlete retire or discontinue participating in contact or collision sports following sport-related concussion? A systematic review

OBJECTIVE

To systematically review the scientific literature regarding factors to consider when providing advice or guidance to athletes about retirement from contact or collision sport following sport-related concussion (SRC), and to define contraindications to children/adolescent athletes entering or continuing with contact or collision sports after SRC.

DATA SOURCES

Medline, Embase, SPORTSDiscus, APA PsycINFO, CINAHL and Cochrane Central Register of Controlled Trials were searched systematically.

STUDY ELIGIBILITY CRITERIA

Studies were included if they were (1) original research, (2) reported on SRC as the primary source of injury, (3) evaluated the history, clinical assessment and/or investigation of findings that may preclude participation in sport and (4) evaluated mood disturbance and/or neurocognitive deficits, evidence of structural brain injury or risk factors for increased risk of subsequent SRC or prolonged recovery.

RESULTS

Of 4355 articles identified, 93 met the inclusion criteria. None of the included articles directly examined retirement and/or discontinuation from contact or collision sport. Included studies examined factors associated with increased risk of recurrent SRC or prolonged recovery following SRC. In general, these were low-quality cohort studies with heterogeneous results and moderate risk of bias. Higher number and/or severity of symptoms at presentation, sleep disturbance and symptom reproduction with Vestibular Ocular Motor Screen testing were associated with prolonged recovery and history of previous concussion was associated with a risk of further SRC.

CONCLUSION

No evidence was identified to support the inclusion of any patient-specific, injury-specific or other factors (eg, imaging findings) as absolute indications for retirement or discontinued participation in contact or collision sport following SRC.

PROSPERO REGISTRATION NUMBER

CRD42022155121.

Cerebrovascular Reactivity and Concussion

Cerebrovascular reactivity (CVR) reflects the change in cerebral blood flow in response to vasodilatory stimuli enabling assessment of the health of the cerebral vasculature. Recent advances in the quantitative delivery of CO2 stimuli with computer-controlled sequential gas delivery have enabled mapping of the speed and magnitude of response to flow stimuli. These CVR advances when applied to patients with acute concussion have unexpectedly shown faster speed and greater magnitude of responses unseen in other diseases that typically show the opposite effects. The strength of the CVR alterations have diagnostic potential in single subjects with AUC values in the 0.90-0.94 range.

Trends in concussion mechanism of injury during the COVID-19 pandemic

OBJECTIVE

The primary objective was to determine the effect of the COVID-19 pandemic on volume, demographics, and mechanisms of injury (MOI) for patients seen at an urban multidisciplinary concussion center. During the first phase of the pandemic in the United States, stay-at-home orders led to decreased group activities and required cancellation of outpatient appointments or initiation of telemedicine visits.

METHODS

This study was a retrospective chart review of 3500 patient electronic medical records (EMR). Patients aged 1-99 years were eligible if they had been seen at New York University Langone Health Concussion Center during March 1-December 31, 2019 (control/pre-pandemic period) or during the same period in 2020 (pandemic period). Injury date, appointment date, age, sex, and MOI were captured; statistical analyses were performed using Stata17 (StataCorp, College Station, TX).

RESULTS

There were 48% fewer visits during the COVID-19 pandemic period compared to the 2019 control period. There was a decreased proportion of pediatric patients (15% control, 6% pandemic; p = 0.007, chi-square test). Fewer concussions were related to team sports (21% control, 5% pandemic; p < 0.001), and a greater proportion were caused by bicycle accidents (4% control, 8% pandemic; p = 0.037) and assault/domestic violence (3% control, 9% pandemic; p < 0.001).

CONCLUSION

The relative proportions of concussion MOI, age distributions, and visit volumes were significantly associated with pre-pandemic vs. pandemic periods, suggesting that COVID-19 changed concussion epidemiology during the pandemic period. This study demonstrates how epidemiologic data may inform future resource allocation during public health emergencies.

Acute effects of concussion among adolescents with attention-deficit/hyperactivity disorder

Adolescents with ADHD have a greater lifetime history of concussion and experience concussion-like symptoms in the absence of a concussion, complicating concussion assessment and management. It is well established that individuals who experience greater acute symptoms following concussion are at risk for slower recovery and persistent symptoms. We examined whether youth with ADHD experience worse acute effects, within the first 72 h following concussion, compared to youth without ADHD. We hypothesized that youth with ADHD would perform worse on neurocognitive testing and endorse more severe symptoms acutely following injury, but the magnitude of change from pre injury to post injury would be similar for both groups, and thus comparable to baseline group differences. The sample included 852 adolescents with pre-injury and post-injury ImPACT results (within 72 h); we also conducted supplementary case-control analyses on a subset of youth with and without ADHD matched on demographics and pre-injury health history. For both samples, there were significant interaction effects for the Verbal Memory and Visual Motor Speed composites (p < 0.01, η²=.01-.07, small-medium effect), such that youth with ADHD showed a greater magnitude of diminished cognitive functioning from pre-injury to post-injury testing. There were no significant differences in the magnitudes of changes from pre injury to post injury with regard to overall symptom reporting (i.e., total symptom severity scores, total number of symptoms endorsed); however, there were group differences in endorsement rates for several individual symptoms. Further research is needed to determine whether such differential acute effects are associated with recovery time in youth with ADHD.

Clinical Outcome Following Concussion Among College Athletes with a History of Prior Concussion: A Systematic Review

BACKGROUND

There is long-standing interest in, and concern about, whether collegiate athletes with a history of concussion will experience worse clinical outcomes, or prolonged recovery, should they sustain a subsequent concussion.

OBJECTIVES

This systematic review examined the association between prior concussion history and clinical outcomes following a subsequent sport-related concussion among college-age student athletes.

STUDY DESIGN

Systematic review.

METHODS

We screened 5,118 abstracts and 619 full-text articles that were appraised to determine whether they met inclusion criteria. We utilized a likelihood heuristic to assess the probability of observing a specific number of statistically significant and nonsignificant studies reporting an association between concussion history and clinical outcomes. We conducted a narrative synthesis of the study findings.

RESULTS

Sixteen studies met the inclusion criteria. Thirteen studies reported the number of participants with a history of prior concussions (≥ 1), which totaled 1690 of 4573 total participants (on average 37.0% of study participants; median = 46.0%, range 5.6-63.8%). On the Newcastle-Ottawa Quality Assessment Scale, the risk of bias ratings ranged from 3 to 9 (mean = 5.4, SD = 1.4). Across all studies, 43.8% (k = 7/16) reported at least one statistically significant result among primary analyses showing an association between concussion history and worse clinical outcome. A minority of studies reporting on symptom duration (4/13, 30.8%) and time to return to play (2/7, 28.6%) found an association between concussion history and worse outcome. Studies included in the review reported limited information pertaining to the characteristics of prior concussions, such as presence or duration of loss of consciousness or posttraumatic amnesia, age at first lifetime concussion, time since most recent past concussion, or length of recovery from prior concussions.

CONCLUSION

The question of whether college athletes with a prior history of concussion have worse clinical outcome from their next sport-related concussion remains unresolved. The published results are mixed and in aggregate show modest evidence for an association. Many studies have small samples, and only three studies were designed specifically to address this research question. Important outcomes, such as time to return to academics, have not been adequately studied. Larger hypothesis-driven studies considering the number of prior concussions (e.g., 3 or more) are needed.

TRIAL REGISTRATION

PROSPERO CRD42016041479, CRD42019128300.

Nutritional interventions to support acute mTBI recovery

When mild traumatic brain injury (mTBI) occurs following an impact on the head or body, the brain is disrupted leading to a series of metabolic events that may alter the brain's ability to function and repair itself. These changes may place increased nutritional demands on the body. Little is known on whether nutritional interventions are safe for patients to implement post mTBI and whether they may improve recovery outcomes. To address this knowledge gap, we conducted a systematic review to determine what nutritional interventions have been prescribed to humans diagnosed with mTBI during its acute period (<14 days) to support, facilitate, and result in measured recovery outcomes.

Methods

Databases CINAHL, PubMed, SPORTDiscus, Web of Science, and the Cochrane Library were searched from inception until January 6, 2021; 4,848 studies were identified. After removing duplicates and applying the inclusion and exclusion criteria, this systematic review included 11 full papers.

Results

Patients that consumed enough food to meet calorie and macronutrient (protein) needs specific to their injury severity and sex within 96 h post mTBI had a reduced length of stay in hospital. In addition, patients receiving nutrients and non-nutrient support within 24-96 h post mTBI had positive recovery outcomes. These interventions included omega-3 fatty acids (DHA and EPA), vitamin D, mineral magnesium oxide, amino acid derivative N-acetyl cysteine, hyperosmolar sodium lactate, and nootropic cerebrolysin demonstrated positive recovery outcomes, such as symptom resolution, improved cognitive function, and replenished nutrient deficiencies (vitamin D) for patients post mTBI.

Conclusion

Our findings suggest that nutrition plays a positive role during acute mTBI recovery. Following mTBI, patient needs are unique, and this review presents the potential for certain nutritional therapies to support the brain in recovery, specifically omega-3 fatty acids. However, due to the heterogenicity nature of the studies available at present, it is not possible to make definitive recommendations.

Systematic review registration

The systematic review conducted following the PRISMA guidelines protocol was registered (CRD42021226819), on Prospero.

Risk factors for prolonged recovery from concussion in young patients

Objectives

For young patients sustaining concussion, assessing recovery is vital in determining safe return to play. Identifying risk factors may aid clinicians in recognising patients at risk for prolonged recovery. The study objective is to identify risk factors for prolonged (>28 days) and extended (>90 days) recovery (defined as symptom duration) and analyse how these risk factors differ between the two groups.

Methods

We retrospectively analysed electronic health record data (n=4937) among patients aged 10–18 years collected at Nationwide Children’s Hospital Sports Medicine concussion clinics between 1 July 2012 and 30 June 2019. Data collected included patient demographics, comorbidities (eg, prior psychiatric diagnoses, prior concussions) and injury characteristics (eg, loss of consciousness, injury setting). We examined patient risk factors for prolonged (>28 days) and/or extended (>90 days) recovery using modified Poisson regression models.

Results

Factors associated with increased risk of prolonged recovery from concussion included prior concussions (adjusted risk ratio (ARR) 1.19, 95% CI 1.02 to 1.38) for two concussions (ARR 1.36, 95% CI 1.14 to 1.61), for >3, and higher initial symptom score (ARR 2.57, 95% CI 2.34 to 2.83) for postconcussion symptom (PCS) scores 21–60 (ARR 2.89, 95% CI 2.54 to 3.29), for PCS>60. Risk factors for extended recovery included history of concussion (ARR 1.50, 95% CI 1.09 to 2.06) for two concussions (ARR 1.75, 95% CI 1.17 to 2.62), for >3 and older age (15–18 years, ARR 1.11, 95% CI 1.05 to 1.18). Additionally, comorbid attention deficit hyperactivity disorder increased risk of prolonged recovery (ARR 1.14, 95% CI 1.01 to 1.29) while anxiety increased risk for extended recovery (ARR 1.47, 95% CI 1.10 to 1.95).

Conclusion

Overall, risk factors for prolonged recovery differ somewhat from risk factors for extended recovery. For patients who present to clinic with concussion, mental health is an important consideration which may impact the timeline for symptom recovery.

Test-retest reliability of the neurotracker compared to the impact test for the management of mild traumatic brain injuries during two consecutive university sport seasons

INTRODUCTION

Neurocognitive assessment tools such as the Neurotracker and ImPACT have been proposed to optimize sports-related mild traumatic brain injury (mTBI) management. Baseline testing is recommended with such assessments to individualize monitoring of athletes' remission. While the ideal timeframe between baseline updates has been studied for the ImPACT, these data are missing for the Neurotracker.

OBJECTIVE

The current study aimed to compare the test-retest reliability of the ImPACT and Neurotracker for two consecutive seasons in university athletes participating in sports at risk for mTBI.

METHODS

At the start of two consecutive seasons, 30 athletes with no recent history of mTBI completed a baseline assessment including the Neurotracker and the ImPACT. The test-retest reliability of the results was analyzed by considering intra-class correlation (ICC), Becker's standardized mean difference (d_B) and Bland-Altman' plot of each outcome.

RESULTS

The Neurotracker and the Visual Motor Speed composite score of the ImPAC were the only outcomes with significative ICCs and acceptable d_B between the two seasons. Neurotracker was the only outcome with a significative bias (+0.179).

CONCLUSION

Our research suggests that the Neurotracker has an acceptable level of test-retest reliability after one year in comparison to the ImPACT.

A window into eye movement dysfunction following mTBI: A scoping review of magnetic resonance imaging and eye tracking findings

Mild traumatic brain injury (mTBI), commonly known as concussion, is a complex neurobehavioral phenomenon affecting six in 1000 people globally each year. Symptoms last between days and years as microstructural damage to axons and neurometabolic changes result in brain network disruption. There is no clinically available objective biomarker to diagnose the severity of injury or monitor recovery. However, emerging evidence suggests eye movement dysfunction (e.g., saccades and smooth pursuits) in patients with mTBI. Patients with a higher symptom burden and prolonged recovery time following injury may show higher degrees of eye movement dysfunction. Likewise, recent advances in magnetic resonance imaging (MRI) have revealed both white matter tract damage and functional network alterations in mTBI patients, which involve areas responsible for the ocular motor control. This scoping review is presented in three sections: Section 1 explores the anatomical control of eye movements to aid the reader with interpreting the discussion in subsequent sections. Section 2 examines the relationship between abnormal MRI findings and eye tracking after mTBI based on the available evidence. Finally, Section 3 communicates gaps in our knowledge about MRI and eye tracking, which should be addressed in order to substantiate this emerging field.

The Incidence, Cost, and Burden of Concussion in Women's Rugby League and Rugby Union: A Systematic Review and Pooled Analysis

BACKGROUND

The extent of concussion injury in the rugby codes for women is unclear.

OBJECTIVE

Our aim was to review all published studies reporting concussion injuries from match and training participation in rugby codes and report the pooled data estimates for rugby league and union concussion injury epidemiology.

METHODS

We conducted a systematic literature analysis of concussion in rugby league and rugby union for published studies from January 1990 to July 2021. Data from 16 studies meeting the inclusion criteria were extracted for women's concussion injuries and were subsequently pooled. Costs from Accident Compensation Corporation (ACC) data were attributed to the results to provide cost estimates.

RESULTS

The pooled analysis match injury incidence of women's concussion was higher for rugby league (10.3 per 1000 match hours) than rugby 15 s (2.8 per 1000 match hours) or rugby 7 s (8.9 per 1000 match hours). There was a fourfold difference in the pooled incidence of concussion in women's rugby league (risk ratio [RR] 4.53, 95% confidence interval [CI] 1.8-11.3]; p = 0.0001) when compared with rugby 15 s. There was also a ninefold higher risk of a concussion during match participation compared with training participation for women's rugby 15 s (RR 9.3, 95% CI 1.29-66.78; p = 0.0070). The total estimated costs for the concussions reported were NZ$1,235,101. For rugby 7 s, the pooled concussive injury burden was 33.2 days.

CONCLUSIONS

Our pooled analysis clarified the extent of concussion injury and the possible associated costs at several levels of the game for women's rugby codes. The pooled mean days lost because of concussions was 33 days. As this was considerably longer than the 7- to 10-day expected timeframe outlined in the Concussion in Sport Consensus statement, these guidelines need to be updated to include sex-specific differences.

Branched-Chain Amino Acids Are Neuroprotective Against Traumatic Brain Injury and Enhance Rate of Recovery: Prophylactic Role for Contact Sports and Emergent Use

Branched-chain amino acids (BCAAs) are known to be neurorestorative after traumatic brain injury (TBI). Despite clinically significant improvements in severe TBI patients given BCAAs after TBI, the approach is largely an unrecognized option. Further, TBI continues to be the most common cause of morbidity and mortality in adolescents and adults. To date, no study has evaluated whether BCAAs can be preventive or neuroprotective if taken before a TBI. We hypothesized that if BCAAs were elevated in the circulation before TBI, the brain would readily access the BCAAs and the severity of injury would be reduced. Before TBI induction with a standard weight-drop method, 50 adult mice were randomized into groups that were shams, untreated, and pre-treated, post-treated, or pre- + post-treated with BCAAs. Pre-treated mice received BCAAs through supplemented water and were dosed by oral gavage 45 min before TBI induction. All mice underwent beam walking to assess motor recovery, and the Morris water maze assessed cognitive function post-injury. On post-injury day 14, brains were harvested to assess levels of astrocytes and microglia with glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA-1) immunohistochemistry, respectively. Pre-treated and pre- +post-treated mice exhibited significantly better motor recovery and cognitive function than the other groups. The pre- + post-treated group had the best overall memory performance, whereas the pre-treated and post-treated groups only had limited improvements in memory compared to untreated animals. Pre- + post-treated brains had levels of GFAP that were similar to the sham group, whereas the pre-only and post-only groups showed increases. Although trends existed, no meaningful changes in IBA-1 were detected. This is the first study, animal or human, to demonstrate that BCAA are neuroprotective and substantiates their neurorestorative benefits after TBI, most likely through the important roles of BCAAs to glutamate homeostasis.

Match and training injury incidence in rugby league: A systematic review, pooled analysis, and update on published studies

In studies reporting rugby league injuries, match injuries varied depending upon participation level. To review and update pooled data estimates for rugby league injury epidemiology and add information for participation levels in match and training environments. A systematic review and pooled analysis for published studies reporting rugby league match and training injuries. Searches were performed in the PubMed, CINHAL, ScienceDirect, Scopus, SPORTDiscus, SpringerLink, and Wiley Online databases. Studies were considered if they reported on rugby league match or training injuries between Jan 1990 to June 2021. Two authors (DK, TC) extracted the study characteristics, numerical data and assessed the article quality, by adhering to the protocol for systematic review of observational studies (MOOSE) and the STrengthening and Reporting of OBservational studies in Epidemiology (STROBE) statement. The 46 studies included a combined exposure of 419,037 h and 18,783 injuries incorporating 158,003 match-hr and 15,706 match injuries (99.4 [95%CI: 97.9–101.0] per 1000 match-hr) and 264,033 training-hr and 3077 training injuries (11.8 [95%CI: 11.4–12.2] per 1000 training-hr). Of included studies, 47.9% utilised a medical attention/treatment injury definition. There was a five-fold difference in injuries for the semi-professional participation level (431.6 per 1000 match-hr) compared with professional (RR: 4.92; p < 0.001) and elite (RR: 3.77; p < 0.001) participation levels. The hooker recorded the highest pooled injury incidence (93.1 per 1000 match-hr). Compared to the 2014 analysis there was a 10-fold increase for head-neck region (RR: 10.7; p < 0.001) injury incidence, and more injuries for the ball carrier (RR: 1.1; p = 0.008) and tackler (RR: 1.2; p = 0.001). There was a three-fold decrease in injury incidence in the first half (RR: 2.9; p < 0.001) and a two-fold decrease in the second half (RR: 2.3; p < 0.001) of matches. While rugby league match and training injury incidence had decreased since 2014, the increase in head injuries, and greater injury rate at the semi-professional level, mean further injury prevention interventions are needed.

•

Based on 46 studies, updated estimates of injury incidence for rugby league-related activities ranged from 14.6 per 1000 match-hr (Junior) to 431.6 per 1000 match-hr (Semi-Professional) participation levels for match activities and 5.3 per 1000 training-hr (Professional) to 97.1 per 1000 training-hr (Elite) participation levels for training activities.

Compared with the pooled analysis in 2014, the current analysis showed:•

The hooker playing position continues to have the highest match injury risk (93.1 per 1000 match-hr).

•

The lower limb (64.5 per 1000 match-hr) continues to be the body region with the highest injury risk.

•

The quadriceps was the most reported injury site (28.5 per 1000 match-hr).

•

The incidence of concussion in studies reporting on rugby league match injuries increased (7.7 vs. 11.6 per 1000 match-hr); and

•

Most concussions took 28 days to recover, which conflicts with the Concussion in Sport Consensus Statement that reported 80%–90% of all concussions recover in seven to ten days.

Quantitative Assessment of Balance for Accurate Prediction of Return to Sport From Sport-Related Concussion

BACKGROUND

Determining when athletes are able to return to sport after sports-related concussion (SRC) can be difficult.

HYPOTHESIS

A multimodal algorithm using cognitive testing, postural stability, and clinical assessment can predict return to sports after SRC.

STUDY DESIGN

Prospective cohort.

LEVEL OF EVIDENCE

Level 2b.

METHODS

Athletes were evaluated within 2 to 3 weeks of SRC. Clinical assessment, Immediate Post Concussion and Cognitive Testing (ImPACT), and postural stability (Equilibrate) were conducted. Resulting data and machine learning techniques were used to optimize an algorithm discriminating between patients ready to return to sports versus those who are not yet recovered. A Fisher discriminant analysis with leave-one-out cross-validation assessed every combination of 2 to 5 factors to optimize the algorithm with lowest combination of type I and type II errors.

RESULTS

A total of 193 athletes returned to contact sports after SRC at a mean 84.6 days (±88.8). Twelve subjects (6.2%) sustained repeat SRC within 12 months after return to sport. The combination of (1) days since injury, (2) total symptom score, and (3) nondominant foot tandem eyes closed postural stability score created the best algorithm for discriminating those ready to return to sports after SRC with lowest type I error (13.85%) and type II error (11.25%). The model was able to discriminate between patients who were ready to successfully return to sports versus those who were not with area under the receiver operating characteristic (ROC) curve of 0.82.

CONCLUSION

The algorithm predicts successful return to sports with an acceptable sensitivity and specificity. Tandem balance with eyes closed measured with a video-force plate discriminated athletes ready to return to sports from SRC when combined in multivariate analysis with symptom score and time since injury. The combination of these factors may pose advantages over computerized neuropsychological testing when evaluating young athletes with SRC for return to contact sports.

CLINICAL RELEVANCE

When assessing young athletes sustaining an SRC in a concussion clinic, measuring postural stability in tandem stance with eyes closed combined with clinical assessment and cognitive recovery is effective to determine who is ready to successfully return to sports.

Post-concussive mTBI in Student Athletes: MRI Features and Machine Learning

Purpose: To determine and characterize the radiomics features from structural MRI (MPRAGE) and Diffusion Tensor Imaging (DTI) associated with the presence of mild traumatic brain injuries on student athletes with post-concussive syndrome (PCS).

Material and Methods: 122 student athletes (65 M, 57 F), median (IQR) age 18.8 (15–20) years, with a mixed level of play and sports activities, with a known history of concussion and clinical PCS, and 27 (15 M, 12 F), median (IQR) age 20 (19, 21) years, concussion free athlete subjects were MRI imaged in a clinical MR machine. MPRAGE and DTI-FA and DTI-ADC images were used to extract radiomic features from white and gray matter regions within the entire brain (2 ROI) and the eight main lobes of the brain (16 ROI) for a total of 18 analyzed regions. Radiomic features were divided into five different data sets used to train and cross-validate five different filter-based Support Vector Machines. The top selected features of the top model were described. Furthermore, the test predictions of the top four models were ensembled into a single average prediction. The average prediction was evaluated for the association to the number of concussions and time from injury.

Results: Ninety-one PCS subjects passed inclusion criteria (91 Cases, 27 controls). The average prediction of the top four models had a sensitivity of 0.80, 95% CI: [0.71, 0.88] and specificity of 0.74 95%CI [0.54, 0.89] for distinguishing subjects from controls. The white matter features were strongly associated with mTBI, while the whole-brain analysis of gray matter showed the worst association. The predictive index was significantly associated with the number of concussions (p < 0.0001) and associated with the time from injury (p < 0.01).

Conclusion: MRI Radiomic features are associated with a history of mTBI and they were successfully used to build a predictive machine learning model for mTBI for subjects with PCS associated with a history of one or more concussions.

Resilience and recovery from sports related concussion in adolescents and young adults

INTRODUCTION

Recovery and return to play are important milestones for athletes who sustain sport-related concussions (SRC). Several factors have been shown to influence resolution of post-concussion related symptoms (PCS), but resilience, a trait that reflects the ability to overcome adversity, is another factor that may influence recovery. The aim of this study was to determine the relationship of resilience with resolution of symptoms during recovery in adolescents and young adults following SRC.

METHOD

This prospective study is part of the North Texas Concussion Registry (ConTex). Subjects (N = 332) aged 13 to 25 years who sustained a SRC within 10 days of presenting to clinic were evaluated at two time points: initial clinical visit and three-month follow-up. Resilience was measured by the self-report Brief Resilience Survey (BRS) and PCS by the Sport Concussion Assessment Tool-5 Symptom Evaluation Post-Concussion Symptom Scale (PCSS). Recovery was determined by self-reported return to sports/physical activity and percent back to normal.

RESULTS

Repeated measures ANCOVA and linear regression models showed that lower resilience ratings at initial visit were associated with a greater number and severity of PCSS symptoms along with higher levels of anxiety and depression symptoms during recovery from SRC. At three months, subjects with lower initial resilience ratings were less likely to report feeling back to normal and had greater aggravation of symptoms from physical and cognitive activity even when they had returned to sports/physical activity.

CONCLUSIONS

Lower resilience was associated with greater symptoms and delayed recovery from SRC. Results suggest that resilience may be another important factor to address in recovery from SRC. Future research is needed to examine the extent to which resilience measured after SRC reflects pre-injury characteristics and to better inform the development of interventions to promote resilience during recovery.

Preliminary Evidence for the Clinical Utility of Tactile Somatosensory Assessments of Sport-Related mTBI

OBJECTIVES

To evaluate the clinical utility of tactile somatosensory assessments to assist clinicians in diagnosing sport-related mild traumatic brain injury (SR-mTBI), classifying recovery trajectory based on performance at initial clinical assessment, and determining if neurophysiological recovery coincided with clinical recovery.

RESEARCH DESIGN

Prospective cohort study with normative controls.

METHODS

At admission (n = 79) and discharge (n = 45/79), SR-mTBI patients completed the SCAT-5 symptom scale, along with the following three components from the Cortical Metrics Brain Gauge somatosensory assessment (BG-SA): temporal order judgement (TOJ), TOJ with confounding condition (TOJc), and duration discrimination (DUR). To assist SR-mTBI diagnosis on admission, BG-SA performance was used in logistic regression to discriminate cases belonging to the SR-mTBI sample or a healthy reference sample (pooled BG-SA data for healthy participants in previous studies). Decision trees evaluated how accurately BG-SA performance classified SR-mTBI recovery trajectories.

RESULTS

BG-SA TOJ, TOJc, and DUR poorly discriminated between cases belonging to the SR-mTBI sample or a healthy reference sample (0.54-0.70 AUC, 47.46-64.71 PPV, 48.48-61.11 NPV). The BG-SA evaluated did not accurately classify SR-mTBI recovery trajectories (> 14-day resolution 48%, ≤14-day resolution 54%, lost to referral/follow-up 45%). Mann-Whitney U tests revealed differences in BG-SA TOJc performance between SR-mTBI participants and the healthy reference sample at initial clinical assessment and at clinical recovery (p < 0.05).

CONCLUSIONS

BG-SA TOJ, TOJc, and DUR appear to have limited clinical utility to assist clinicians with diagnosing SR-mTBI or predicting recovery trajectories under ecologically valid conditions. Neurophysiological abnormalities persisted beyond clinical recovery given abnormal BG-SA TOJc performance observed when SR-mTBI patients achieved clinical recovery.

In search of scientific objectivity: Is there such a property for paediatric concussion?

Concussions are a significant public health problem worldwide. This brain injury is problematic in the paediatric population for a variety of reasons; however, the enquiry into these problems has been mainly through the biomedical perspective. This approach has impacted nursing knowledge and practice of children and youth with a concussion, primarily since other perspectives are viewed as not being objective. In this manuscript, I draw on Thomas Kuhn's view of objectivity to evaluate the biomedical perspective of concussion. I utilize current research and clinical examples to illustrate the advantages and drawbacks of this perspective for nursing. From this discussion, I propose an alternative perspective to capture the complexity of paediatric concussions for nursing, a systems perspective. Although I argue for an alternative perspective to approach paediatric concussions for nursing, I maintain that the biomedical perspective can be incorporated as one part of nursing knowledge and practice for paediatric concussion.

The More, the Better: High-Dose Omega-3 Fatty Acids Improve Behavioural and Molecular Outcomes in Preclinical Models in Mild Brain Injury

PURPOSE OF REVIEW

Mild traumatic brain injury (mTBI) is a continuing healthcare concern worldwide contributing to significant cognitive and neurological impairment, consequently affecting activities of daily living. While mTBI recovery is becoming well studied, there are no interventions to reduce the known impairments of mTBI. Omega-3 fatty acids (N-3FA) are safe and beneficial for brain health; however, their potential effects in a pathophysiological environment such as that seen post-mTBI are unknown.

RECENT FINDINGS

Preclinical studies using rodent models are key to understanding molecular mechanisms underlying improvements post-injury. Studies to date have shown improved outcomes in rodent models following mTBI protocols, but these data have not been quantified using a systematic review and meta-analysis approach. Our systematic review assessed 291 studies identified from the literature. Of these studies, 18 studies met inclusion criteria. We conducted a meta-analysis examining the effect of high-dose n-3FA vs placebo on neurological, cognitive and molecular changes following mTBI. Quality of studies was rated as moderate to high quality, and while mostly compliant, some areas of risk of bias were identified. Results showed that preclinical doses of 10-370 mg/kg/day of n-3FA per day in rodents (equivalent to high clinical doses) resulted in improvements in neurological and cognitive performance (pooled effect sizes ranging between 1.52 and 3.55). Similarly, improvements in molecular and inflammatory markers were observed in treated rodents vs control (pooled effect sizes: 3.73-6.55). Overall, these findings highlight the potential for high-dose n-3FA for human clinical studies following mTBI.

Effects of Stricter Management Guidelines on Return-to-Competition Timeframes Following Concussion in Professional Australian Rules Football: An Exploratory Analysis

Background

Management of concussion remains a serious issue for professional sports, particularly with the growing knowledge on the consequences of repetitive concussion. One primary concern is the subjective assessment of recovery that dictates the time until a concussed athlete is returned-to-competition. In response to this concern, the Australian Football League (AFL) changed its policy in 2020 such that medical clearance for return-to-competition was extended from 1 day, to a minimum of 5 days, prior to the next scheduled match.

Objective

We sought to explore the impact of the AFL policy change by asking whether time to return-to-competition after concussion was increased in the 2020 season relative to previous years.

Methods

Retrospective data on injury and return-to-competition were sourced from publicly available tables published by the AFL. Our primary exploration compared the number of matches missed and the number of days missed in concussed players across 2017–2020 inclusive, with secondary exploration analysing the proportion of players returning to play 12 days or longer.

Results

Analysis of data from 166 concussed players revealed no increase in the number of matches missed in 2020 relative to previous years as would have been expected from an extended recovery protocol. Comparing 2020 relative to 2017–2019, we found that there was an overall moderate reduction in median time to return-to-competition (RTC) in 2020 (10 vs 13 days, respectively d = − 0.345) and a significant reduction in players taking more than 12 days to RTC (p = 0.046).

Conclusion

This exploratory study demonstrates that clubs may not have followed policy change around concussion management designed to increase time to RTC. Ongoing auditing is required to ensure player clearance meets policy goals, highlighting the need for objective measures for RTC after concussion.

The Influence of Timing of Reporting and Clinic Presentation on Concussion Recovery Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

Identifying risk factors for prolonged recovery following concussion can assist clinicians with appropriate management strategies. It is thought that athletes who continue to participate following a hit to the head or body may take longer to recover following a concussion diagnosis.

OBJECTIVE

To systematically review the body of literature regarding the effect of delayed reporting and delayed presentation to medical providers on concussion recovery times.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

PubMed, Ovid Medline, SPORTDiscus, Cochrane Central Register of Controlled Trials and hand searches of reference lists. All the searches were performed in April 2020.

ELIGIBILITY CRITERIA FOR SELECTED STUDIES

Studies included an investigation of immediate versus delayed reporting or early versus late presentation following a concussion, were published in the past ten years, and were level 4 evidence or higher.

RESULTS

12 studies were included. Patients who continued play or delayed reporting their concussion had significantly longer recovery times (standardized mean difference = 0.36 days (95%CI 0.066, 0.662) than those who immediately reported or were removed from play (p = 0.017). Expressed in raw scores, those who immediately reported recovered in 5.4 days (95% CI - 10.14, - 0.75) fewer than delayed reporters. Comparable results were found for post-concussion symptom scores (p = 0.034) with immediate reporters demonstrating lower symptom severity scores. Our qualitative synthesis found patients who presented earlier to a concussion specialist tended to recover faster than those who presented later.

CONCLUSIONS

Patients who delayed reporting or continued play had longer recovery times compared to their immediately-reporting peers. Providers should ask concussion patients approximately how long they waited to report their injury, and also focus educational efforts on encouraging immediate reporting of concussion.

Concussion in the Athletic Training Room: a Team Physician Narrative

PURPOSE OF THE REVIEW

Concussion evaluation and management has changed significantly. Understanding proper recognition, evaluation, and management allows for improved provision of care to patients. This paper will approach this topic from a sideline to training room management versus the traditional clinic evaluation RECENT FINDINGS: Research is continuing to refine and examine tools to assist in proper concussion evaluation. Concussion recovery protocols are becoming more conservative as patients are taking longer to recover than previously thought. Treatment of concussion is becoming more sophisticated and patient involved. Concussion research has increased dramatically over the last 30 years changing our approach to diagnosis and treatment. The area of concussion will continue to evolve as research continues to look at effective tools and markers for diagnosis and effective treatment protocols become substantiated through research.

Time-to-Event Analyses: Return to Unrestricted Participation After Sport-Related Concussion in a Cohort of High School Athletes

CONTEXT

Understanding time loss resulting from sport-related concussion (SRC) within individual sports allows high school athletic trainers to provide accurate and evidence-based clinical information. Currently, research regarding patterns of clinical recovery outcomes in high school student-athletes across sports is lacking.

OBJECTIVE

To describe the time to authorized unrestricted return to participation (RTP) after SRC in a large cohort of high school student-athletes in a variety of sports using a time-to-event analysis.

DESIGN

Descriptive epidemiology study.

SETTING

Aggregate injury and player exposure data from the Michigan High School Athletic Association Head Injury Reporting System.

PATIENTS OR OTHER PARTICIPANTS

High school student-athletes.

MAIN OUTCOME MEASURE(S)

Dates for SRC injury events and authorized unrestricted RTP were entered into the Head Injury Reporting System for each case and were used to calculate time to unrestricted RTP. Survival analysis indicated the time to authorized RTP for males and females in weekly increments across sports and academic years. Separate Kaplan-Meier analyses adjusted for SRC cases with a history of concussion also identified the proportions of student-athletes who obtained authorized medical clearance in weekly increments.

RESULTS

A total of 15 821 SRCs, 10 375 (65.6%) in males and 5446 (34.4%) in females, were reported during the 2015-2016 through 2018-2019 academic years. The median time to authorized unrestricted RTP was 11 days for all patients. Approximately 30% of concussed student-athletes were not cleared for unrestricted RTP by 14 days after their SRC diagnosis, with 13% taking longer than 21 days to return to unrestricted RTP after SRC.

CONCLUSIONS

The results from this multisite, state-based injury surveillance system indicated that it is not abnormal for high school student-athletes to take longer than 14 days to fully recover from an SRC. This information may be useful for educating high school student-athletes and sport stakeholders, normalizing SRC recovery trajectory perceptions, and establishing realistic RTP timeline expectations.

Stakeholder Recommendations to Increase the Accessibility of Online Health Information for Adults Experiencing Concussion Symptoms

Background: Concussion is a global public health problem. In Canada, concussion is among the top five reasons for workplace time-loss. Concussion results in physical, cognitive, and/or emotional symptoms that temporarily worsen with physical and mental exertion, such as viewing electronic screens. The Internet is the primary source of consumer health information. Studies on the end-user needs of adults with brain injuries in regards to digital health technologies largely focus on informational content. There is little to no research on the accessibility of screen-based informational websites and smartphone applications among this population.

Objective: The aim of this research was to involve stakeholders in the design of a comprehensive educational resource to guide concussion recognition, recovery, and return-to-work, called the Concussion Awareness Training Tool for Workers and Workplaces (CATT WW). In order to ensure both relevant content and appropriate delivery of the information to the target groups, participants were asked whether adaptations could increase the accessibility of online health information for the general adult population experiencing concussion symptoms.

Methods: Data have been generated through semi-structured in-depth interviews and focus groups with participants from across British Columbia (BC): workers from various industries who were in the concussion recovery process or had returned to work (n = 31); and healthcare or workplace professionals who support concussion diagnosis, recovery, and return-to-work (n = 16). Data were analyzed using NVivo 12. Before commencing data collection, ethical permission was granted by the University of British Columbia Research Ethics Board (H18-00604), and approval was received from WorkSafeBC Research Services.

Results: Participants (n = 47) recommended twenty adaptations or supplements to electronic screen-based digital health technologies.

Conclusion: Given the high prevalence of concussion among the working adult population, the symptom exacerbation commonly caused by prolonged use of electronic screens, and the demand for online educational resources, these findings can guide clinicians, researchers, technology developers, employers, and occupational health and safety committees to further support adults in concussion recovery and return-to-work.

The use of inertial measurement units to assess gait and postural control following concussion

BACKGROUND

Impairments in gait and balance function are typical after concussion. There is evidence that these neuromuscular deficits persist past the typical time of symptom resolution. The ability to quantify these changes in gait and balance may provide useful information when making return to play decisions in clinical settings.

RESEARCH QUESTION

Are changes in gait function and postural control evident across the course of a concussion management program?

METHODS

A retrospective analysis of a convenience sample of 38 patients who were seen for concussion between October 2017 and May 2019 was performed. Gait and balance measures were assessed at their initial clinic visit post-injury and at their clearance visit using inertial measurement units. During dual-task walking trials, the medial-lateral motion of the center of mass and gait velocity were measured. Postural sway complexity and jerk index were measured during both eyes-open and eyes-closed balance trials.

RESULTS

Paired samples t-tests and Wilcoxon signed rank tests were used to determine whether statistically significant changes occurred for the gait and balance variables, respectively. Medial-lateral sway decreased (4.4 ± 1.3 cm to 4.0 ± 1.2 cm, p = 0.018) and gait velocity increased (0.78 ± 0.23 m/s to 0.91 ± 0.18 m/s, p <  0.001) from initial to clearance testing. Jerk index decreased (6.41 ± 11.06 m²/s⁵ to 5.73 ± 4.28 m²/s⁵, p = 0.031) and (11.87 ± 26.42 m²/s⁵ to 7.87 ± 8.38 m²/s⁵, p = 0.003) from initial to clearance testing for the eyes-open and eyes-closed conditions, respectively. Complexity index increased (2.38 ± 1.08-2.86 ± 0.72, p = 0.010) from initial to clearance testing for the eyes-closed condition. There was no change in complexity index for the eyes-open condition.

SIGNIFICANCE

These preliminary results support the potential use of measures of gait and postural control to assess recovery following a concussion in a clinical setting.

Use of the King-Devick test for the identification of concussion in an amateur domestic women's rugby union team over two competition seasons in New Zealand

OBJECTIVE

To investigate the use of the King-Devick (K-D) test for sideline assessment of concussive injuries in a New Zealand amateur women's rugby union team.

DESIGN

Prospective cohort observational.

METHODS

All players were K-D tested during pre-season using a tablet (iPad; Apple Inc., Cupertino, CA). Differences in K-D scores and test-retest reliability were calculated for baseline test scores, baseline, and post-injury (concussion) sideline assessment and baseline and post-season testing scores for tests by year and as a combined score.

RESULTS

One training-related (0.3 per 1000 training-hrs) and nine match-related (16.1 per 1000 match-hrs) concussions were recorded. The K-D post-injury (concussion) sideline test score were significantly slower than established baseline (-4.4 [-5.8 to -3.4] s; χ²₍₁₎ = 42.2; p < 0.0001; t₍₉₎ = -4.0; p = 0.0029; d = -0.8). There was good-to-excellent reliability of the K-D test for baseline (ICC: 0.84 to 0.89), post-injury (concussion) sideline assessment (ICC: 0.82 to 0.97) and post-season evaluation (ICC: 0.79 to 0.83).

DISCUSSION

By utilising the baseline to post-injury (concussion) assessment comparisons, any player with a post-injury (concussion) assessment slowing of their K-D test time, regardless of whether the player has, or has not had a witnessed insult, should be withheld from any further participation until they are evaluated by a medical professional trained in the management of concussion.

CONCLUSION

This study has provided additional evidence to support the use of the K-D test as a frontline method of assessing concussion with good to excellent reliability of the test for baseline, side-line assessment and post-season evaluation.