The performance of the World Rugby Head Injury Assessment Screening Tool: a diagnostic accuracy study

Innovation in sport medicine and science: a global social network analysis of stakeholder collaboration in rugby union

Objectives

To investigate the network of stakeholders involved in rugby union research across the globe.

Methods

Using author affiliations listed on scientific publications, we identified the organisations that contributed to rugby union research from 1977 to 2022 and examine collaboration through coauthorship indicators. We determined the locations and sectors of identified organisations and constructed a collaboration network. Network metrics, including degree centrality and betweenness centrality, are computed to identify influential organisations and measure intersector collaboration.

Results

There is an increase in scientific knowledge creation and collaboration between organisations for rugby union research over time. Among the sectors, the university, professional sports team and sports governing body sectors exhibit the highest intersectoral and intrasectoral density. Predominantly, influential actors are located in England, Australia, France, New Zealand, Ireland and South Africa. Australian Catholic University, Leeds Beckett University, Stellenbosch University, Swansea University, University College London and the University of Cape Town emerge as influential actors between 2016 and 2022.

Conclusions

Our study underscores the ongoing growth of scientific knowledge generation in rugby union, primarily led by organisations in tier 1 rugby-playing nations within the university sector. Intersectoral collaboration with sports governing bodies plays a crucial role, acting as a broker between sectors. However, the overall collaboration landscape between and within sectors is low. These results highlight an opportunity for improved collaboration opportunities, as the organisations driving knowledge creation have been identified.

Examining Whether Loss of Consciousness Is Associated With Worse Performance on the SCAT5 and Slower Clinical Recovery After Concussion in Professional Athletes

Video surveillance has almost universally been employed by professional sports to identify signs of concussion during competition. This study examined associations between video-identified possible loss of consciousness (LOC), acute concussion evaluation findings, and recovery time in concussed professional rugby league players. Medical personnel and sideline video operators identified head impact events sustained during three seasons of National Rugby League (NRL) matches to determine the need for further medical evaluation. If a concussion was suspected, players were removed from play and underwent a Head Injury Assessment, including the Sports Concussion Assessment Tool, Fifth Edition (SCAT5). Video footage was later examined to identify signs of possible LOC (i.e., observed LOC, no protective action in the fall, and unresponsiveness or lying motionless). Possible LOC was identified in 99 of the 1706 head impact events (5.8%). The median duration of apparent unresponsiveness was 4.2 sec (M = 7.4, standard deviation [SD] = 12.8, interquartile range [IQR] = 2.5-6.6). In the 661 athletes for whom SCAT5 data were available, those with possible LOC endorsed more SCAT5 symptoms and performed worse on Maddocks questions, Standardized Assessment of Concussion (SAC) total scores, orientation, immediate recall, concentration, and delayed recall. For the 255 players with medically diagnosed concussions, SCAT5 data were available for 245. Concussed players with possible LOC performed significantly worse on Maddocks questions. However, there were no group differences in SCAT5 symptom endorsement, SAC total scores, orientation, immediate recall, concentration, delayed recall, or the modified version of the Balance Error Scoring System (mBESS) total errors. Further, the presence or absence of possible LOC was not associated with number of games missed or time to medical clearance for match play. The duration of possible LOC was not associated with the number of games missed or time to medical clearance for match play. According to video review in NRL players, brief LOC might be more common than previously thought. The present study reveals possible LOC is not predictive of missed games or time to recover following concussion.

Traumatic Brain Injury: Acupuncture Treatment

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. It is estimated that half of the people in the world will experience at least 1 episode of TBI during their lifetimes. While the primary injury to the brain parenchyma is usually irreversible, the secondary effects, which involve cellular dysfunction, derangement of blood flow, and blood-brain barrier changes in ionic flux and elevated levels of free radicals are potentially amenable to treatment. At present, there are no neuroprotective agents in mainstream medicine to interrupt these secondary processes and improve the patient's neurologic outcome. Acupuncture holds promise to fill this gap and scientific evidence to that effect is presented. Sports-related brain injury is discussed in detail.

Epidemiology of International Match Injuries in Scottish Rugby: A Prospective Cohort Study

Fifteen-a-side rugby union ("rugby") is a full-contact sport played separately by men and women, with large injury incidences reported previously. Context specific injury surveillance fulfils governing bodies' duty of care to understand risks to player welfare, yet no contemporary match injury epidemiology studies exist for international players in Scotland. The current study therefore aimed to describe the incidence, severity, burden and nature of match injuries sustained by Scotland's men's and women's national teams. A prospective cohort study of injuries recorded in matches across the 2017/18 and 2018/19 seasons was undertaken, with injury and exposure definitions in line with the international consensus for injury surveillance in rugby. Injury incidence was 120.0 (men) and 166.7/1,000 player match hours (women), injury severity was 12.0 (median) and 31.2 days (mean) for men, and 11.0 (median) and 30.2 days (mean) for women. Injury burden was 3,745 (men) and 5,040 days absence/1,000 player match hours (women). Concussion was the most common specific injury for men (22.5/1,000 hours) and women (26.7/1,000 hours). No statistical differences were found for incidence or severity measures between sexes. Injury incidence was greater than recent Rugby World Cup studies. High incidences of concussion reinforces the need for prevention strategies targeting this injury.

Sensitivity and Specificity of Exercise Intolerance on Graded Exertion Testing for Diagnosing Sport-Related Concussion: A Systematic Review and Exploratory Meta-Analysis

Abstract There is no single gold standard test to diagnose sport-related concussion (SRC). Concussion-related exercise intolerance, that is, inability to exercise to the individual's appropriate level due to exacerbation of concussion-like symptoms, is a frequent finding in athletes early after SRC that has not been systematically evaluated as a diagnostic test of SRC. We performed a systematic review and proportional meta-analysis of studies that evaluated graded exertion testing in athletes after SRC. We also included studies of exertion testing in healthy athletic participants without SRC to assess specificity. Pubmed and Embase were searched in January 2022 for articles published since 2000. Eligible studies included those that performed graded exercise tolerance tests in symptomatic concussed participants (> 90% of subjects had an SRC, seen within 14 days of injury), at the time of clinical recovery from SRC, in healthy athletes, or both. Study quality was assessed using the Newcastle-Ottawa Scale. Twelve articles met inclusion criteria, most of which were of poor methodological quality. The pooled estimate of incidence of exercise intolerance in participants with SRC equated to an estimated sensitivity of 94.4% (95% confidence interval [CI]: 90.8, 97.2). The pooled estimate of incidence of exercise intolerance in participants without SRC equated to an estimated specificity of 94.6% (95% CI: 91.1, 97.3). The results suggest that exercise intolerance measured on systematic testing within 2 weeks of SRC may have excellent sensitivity for helping to rule in the diagnosis of SRC and excellent specificity for helping to rule out SRC. A prospective validation study to determine the sensitivity and specificity of exercise intolerance on graded exertion testing for diagnosing SRC after head injury as the source of symptoms is warranted.

Acute evaluation of sport-related concussion and implications for the Sport Concussion Assessment Tool (SCAT6) for adults, adolescents and children: a systematic review

OBJECTIVES

To systematically review the scientific literature regarding the acute assessment of sport-related concussion (SRC) and provide recommendations for improving the Sport Concussion Assessment Tool (SCAT6).

DATA SOURCES

Systematic searches of seven databases from 2001 to 2022 using key words and controlled vocabulary relevant to concussion, sports, SCAT, and acute evaluation.

ELIGIBILITY CRITERIA

(1) Original research articles, cohort studies, case-control studies, and case series with a sample of >10; (2) ≥80% SRC; and (3) studies using a screening tool/technology to assess SRC acutely (<7 days), and/or studies containing psychometric/normative data for common tools used to assess SRC.

DATA EXTRACTION

Separate reviews were conducted involving six subdomains: Cognition, Balance/Postural Stability, Oculomotor/Cervical/Vestibular, Emerging Technologies, and Neurological Examination/Autonomic Dysfunction. Paediatric/Child studies were included in each subdomain. Risk of Bias and study quality were rated by coauthors using a modified SIGN (Scottish Intercollegiate Guidelines Network) tool.

RESULTS

Out of 12 192 articles screened, 612 were included (189 normative data and 423 SRC assessment studies). Of these, 183 focused on cognition, 126 balance/postural stability, 76 oculomotor/cervical/vestibular, 142 emerging technologies, 13 neurological examination/autonomic dysfunction, and 23 paediatric/child SCAT. The SCAT discriminates between concussed and non-concussed athletes within 72 hours of injury with diminishing utility up to 7 days post injury. Ceiling effects were apparent on the 5-word list learning and concentration subtests. More challenging tests, including the 10-word list, were recommended. Test-retest data revealed limitations in temporal stability. Studies primarily originated in North America with scant data on children.

CONCLUSION

Support exists for using the SCAT within the acute phase of injury. Maximal utility occurs within the first 72 hours and then diminishes up to 7 days after injury. The SCAT has limited utility as a return to play tool beyond 7 days. Empirical data are limited in pre-adolescents, women, sport type, geographical and culturally diverse populations and para athletes.

PROSPERO REGISTRATION NUMBER

CRD42020154787.

Blood Biomarkers for Return to Play after Concussion in Professional Rugby Players

We prospectively evaluated a panel of seven blood biomarkers (S100 calcium-binding protein B [S100B], neuron specific enolase [NSE], spectrin breakdown products [SBDP], ubiquitin C-terminal hydrolase L1 [UCHL1], glial fibrillary acidic protein [GFAP], neurofilament light chain [NFL], and tubulin-associated unit [Tau]) for sport-related concussion (SRC) in a large multi-centric cohort of 496 professional rugby players from 14 French elite teams. Players were sampled twice during the season (beginning and end) away from any sport practice. From these two baseline samples, we evaluated the intra-individual variability to establish the effect of rugby on blood biomarkers over a season. Only S100B and GFAP remained stable over the course of a season. During the period of the study, a total of 45 SRC cases was reported for 42 players. In 45 SRCs, the head injury assessment (HIA) process was performed and blood collection was realized 36 h after the concussion (HIA-3 stage). For each biomarker, raw concentrations measured 36 h after SRC were not significantly different between players with a non-resolutive SRC (n = 28) and those with a resolutive SRC (n = 17; p between 0.06 and 0.92). In a second step, blood concentrations measured 36 h after SRC were expressed according to the basal concentrations as an individual percentage change (PCH36[%]), calculated as follows: PCH36 = 100 × (([Biomarker]36h - [Biomarker]basal)/[Biomarker]basal). S100B and NFL concentrations expressed as PCH36[%] were significantly different between non-resolutive and resolutive SRCs (p = 0.006 and 0.01 respectively), with a positive delta found in non-resolutive SRCs. Among the two biomarkers, it is important to note that only the S100B protein was stable during the season. In the context of our study, during HIA-3 assessment, S100B seems to perform better than NSE, SBDP, UCHL1, GFAP, NFL, and Tau as biomarker for SRC. From a clinical standpoint, the S100B modification over baseline may be valuable, at 36 h after concussion to distinguish non-resolutive SRC from resolutive SRC.

Is the Sport Concussion Assessment Tool 5th Edition a useful concussion assessment tool in head‐injured patients presenting to the emergency department?

OBJECTIVE

Concussion is a common ED complaint, but diagnosis is challenging as there are no validated objective measures. Use of concussion tools derived from sports medicine is common, but these tools are not well validated in ED settings. The aim of this study was to assess the ability of the Sport Concussion Assessment Tool 5th Edition (SCAT5) to identify concussion in ED patients presenting following head injury.

METHODS

We conducted a prospective observational study of head-injured adult patients presenting to ED between March and July 2021. ED diagnosis of concussion was used as the diagnostic standard, and we assessed the diagnostic performance of the SCAT5 test and its three subsections (Standardised Assessment of Concussion (SAC), Post-Concussion Symptom Scale (PCSS) and Modified Balance Error Scoring System (mBESS)) against this.

RESULTS

Thirty-two head-injured participants were enrolled, 19 of whom had a discharge diagnosis of concussion, alongside 17 controls. Median time for SCAT5 testing was 21 (interquartile range 16-27) min. Fifteen (30.6%) participants were interrupted during testing. Area under the curve (AUC) (95% confidence interval) for the SAC, PCSS and mBESS were 0.51 (0.34-0.68), 0.92 (0.84-0.99) and 0.66 (0.47-0.85), respectively. Sensitivity and specificity of sections were as follows: entire SCAT5 (100.0%, 20.0%), SAC (48.1%, 60.0%), PCSS (89.7%, 85.0%) and mBESS (83.3%, 58.8%). Using PCSS alone would have identified 17 of 19 concussions.

CONCLUSION

The SCAT5 test had a low specificity, was long and was frequently interrupted. We suggest it is not an ideal assessment to use in ED. The PCSS score performed well and was easy to complete. It may be useful as a standalone tool to simplify ED concussion identification.

An assessment of current concussion identification and diagnosis methods in sports settings: a systematic review

Background

Concussion in sport is an ongoing global concern. The head injury assessment (HIA) by the field of play is acknowledged as the first step in recognising and identifying concussion. While previous systematic literature reviews have evaluated the sensitivity of side-line screening tools and assessment protocols, no systematic review has evaluated the research designs and assessments used in a field setting. This systematic review investigated existing screening and diagnostic tools used in research as part of the HIA protocol to identify concussion that are currently used in professional, semi-professional and amateur (club) sports settings.

Methods

A systematic searching of relevant databases was undertaken for peer-reviewed literature between 2015 and 2020.

Results

Twenty-six studies met the inclusion criteria. Studies were of moderate to good quality, reporting a variety of designs. The majority of studies were undertaken in professional/elite environments with medical doctors and allied health practitioners (e.g., physical therapists) involved in 88% of concussion assessments. While gender was reported in 24 of the 26 studies, the majority of participants were male (77%). There was also a variety of concussion assessments (n = 20) with the sports concussion assessment tool (SCAT) used in less than half of the included studies.

Conclusion

The majority of studies investigating concussion HIAs are focused on professional/elite sport. With concussion an issue at all levels of sport, future research should be directed at non-elite sport. Further, for research purposes, the SCAT assessment should also be used more widely to allow for consistency across studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-022-00514-1.

Effect of a new concussion substitute rule on medical assessment of head collision events in Premier League football

OBJECTIVE

To investigate the utilisation of additional permanent concussion substitutes (APCSs) and its efficacy with regards to rate and duration of medical assessment of head collision events (HCEs) in the 2020-2021 Premier League season. The present APCS rule allows players with a suspected concussion to be removed from a match without counting towards a team's allocated substitutions.

METHODS

Eighty Premier League matches, 40 prior to additional permanent concussion substitutes implementation (Pre-APCS) and 40 after (Post-APCS), were randomly selected and analysed by a team of trained reviewers for HCEs. Data on HCE incidence, rates of medical assessment, duration of medical assessment and return to play were collected for each match. Data for the Pre-APCS and Post-APCS groups were compared to analyse differences in assessment of HCEs.

RESULTS

During the 2020-2021 Premier League season, three APCSs were used. There were 38 HCEs identified in the Pre-APCS group (0.95 per match, 28.79 per 1000 athlete-hours of exposure) and 42 in the Post-APCS group (1.05 per match, 31.82 per 1000 athlete-hours of exposure). Incidence of HCEs (p=0.657), rates of medical assessment (23.7% Pre-APCS vs 21.4% Post-APCS; p=0.545) and duration of medical assessment (median 81 s Pre-APCS vs 102 s Post-APCS; p=0.466) did not significantly differ between the two groups.

CONCLUSIONS

The implementation of APCSs in the Premier League did not impact the rate or duration of medical assessement of HCEs. Despite the introduction of APCSs, the consensus protocols for HCE assessment were rarely followed. We recommend changes to APCS and its implementation that would be aimed at protecting player health.

Head Injury Assessment in the Elite Level Rugby Union in Japan: Review of 3 Seasons

Head Injury Assessment (HIA) is the screening tool for head injury during a rugby game. The purpose of this study was to investigate the epidemiology of HIA in the Japan Rugby Top League (JRTL). The incidences of HIA, defined concussion (per 1,000 player-hours) and repeated concussions were evaluated in three seasons (2016-17, 2017-18, 2018-19; total 360 games). The HIA incidence rates were 12.7 (95% confidence interval 9.5-15.9), 20.8 (16.8-24.9), and 25.0 (20.5-29.5) in each season. HIA-1 criteria 2, which is applied for suspected concussion cases, was performed for 46 cases in the 2016-17 season, 81 cases in the 2017-18 season, and 88 cases in the 2018-19 season. The concussion incidence rates were significantly greater in the 2017-18 season (9.6/1000 player-hours, 95% confidence interval 6.8-12.4) and the 2018-19 season (14.4, 11-17.8) compared to the 2016-17 season (4.8, 2.8-6.8). The number of repeated concussion cases in the same season was 1 in the 2016-17 season and 4 in both the 2017-18 and 2018-19 seasons. This study confirmed significantly higher HIA and concussion incidence rates over time. Although the HIA system might have been established in the three seasons in JRTL, comprehensive management needs to be improved to prevent repeated concussions.

How is Video Efficient to Diagnose Sport-Related Concussion? A Cross-Sectional Study in the French TOP14 Rugby Championship

OBJECTIVE

To describe the frequency of clinical signs and the accuracy of video diagnosis of sport-related concussion.

DESIGN

An observational cross-sectional study.

SETTING AND PARTICIPANTS

Videos from a database of all suspected sport-related concussion in TOP14 matches (French professional male rugby Championship) were used, from 2012 to 2015 seasons. The videos were analyzed by 4 observers, blinded to the concussion diagnosis, after a training phase, and an inter-rater reliability analysis.

INTERVENTIONS

N/A.

MAIN OUTCOME MEASURES

Video analysis for clinical signs and presumed diagnosis of sport-related concussion. The observer's diagnosis was compared with the team physicians' diagnosis.

RESULTS

Four hundred seventeen videos were analyzed with 142 concussed players. Sport-related concussions happened mostly from an impact to the head (seen by the observers in 98.4%), against an opponent (73.2%), and during a tackle (74.6%). Video signs were observable in 98.6% for suspected loss of consciousness, tonic posturing (95%), ataxia (77.2%), dazed look (35.7%), abnormal behavior (18.2%), and seizures (96.2%). Ataxia was seen in 77.7% of concussed players, suspected loss of consciousness in 61.4%, dazed look in 63.2%, abnormal behavior in 55%, and tonic posturing in 7.1%. The observers diagnosed 79.8% of concussions.

CONCLUSIONS

We described the frequency of video clinical signs of sport-related concussion, with a good accuracy of the blinded observers for the diagnosis. This emphasizes the importance of pitch-side video analysis as an extra tool for sport-related concussion diagnosis.

Injuries in Elite Men's Rugby Union: An Updated (2012-2020) Meta-Analysis of 11,620 Match and Training Injuries

Background

The most recent meta-analytic review of injuries in elite senior men’s Rugby Union was published in 2013. The demands of the game at the elite level are continually changing alongside law amendments and developments in player preparation. As such, an updated meta-analysis of injury data in this setting is necessary.

Objective

To meta-analyse time-loss injury data in elite senior men’s Rugby Union between 2012 and 2020.

Methods

Electronic databases were searched using the keywords ‘rugby’ and ‘inj*’. Nineteen studies met the inclusion criteria. Injury incidence rate data were modelled using a mixed-effects Poisson regression model. Days missed data were modelled using a general linear mixed model.

Results

The included data encompassed a total of 8819 match injuries and 2801 training injuries. The overall incidence rate of injuries in matches was 91 per 1000 h (95% confidence interval (CI) 77–106). The estimated mean days missed per match injury was 27 days (95% CI 23–32). The overall incidence rate of match concussions was 12 per 1000 h (95% CI 9–15). The overall incidence rate of training injuries was 2.8 per 1000 h (95% CI 1.9–4.0). Playing level was not a significant effect modifier for any outcome.

Conclusions

The injury incidence rate and mean days missed per injury in the present meta-analysis were higher, but statistically equivalent to, the 2013 meta-analysis (81 per 1000 h and 20 days, respectively). The injury incidence rate for match injuries in elite senior men’s Rugby Union is high in comparison to most team sports, though the training injury incidence rate compares favourably. The tackle event and concussion injuries should continue to be the focus of future preventative efforts.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01603-w.

Expansion of cognitive testing for off-field concussion screening in elite rugby players: A cohort study

OBJECTIVES

Current off-field concussion screening instruments have sub-optimal accuracy and additional testing domains may be necessary to detect the full spectrum of concussion presentations. This study aimed to determine if additional cognitive tests add utility to off-field screening for sport-related concussion.

DESIGN

Reproducibility and diagnostic accuracy cohort studies were performed in the 2017 and 2018 seasons of the Super Rugby competition, conducted in Argentina, Australia, Japan, New Zealand, and South Africa.

METHODS

Abridged versions of Stroop (score, time), Spatial Memory (score, failed trials), and Trail Making Trial-B (time, errors) cognitive tests, modified for off-field use, were examined. Players performed baseline testing prior to each season. Cases undergoing off-field screening as part of the World Rugby Head Injury Assessment Process underwent evaluation with the same cognitive tests during competition matches. Agreement between repeated pre-season baseline measurements, and the diagnostic accuracy of off-field testing against a clinical reference standard of concussion, was evaluated.

RESULTS

Data were available for repeated preseason baseline testing in 644 players, and 100 cases undergoing off-field concussion screening. There was little individual agreement across pre-season baseline assessments for all tests (Lin's correlation and Gwets AC1 coefficients ranging between 0.2 and 0.3). There was significantly worse performance for the time taken to complete the modified Stroop Test in concussed players undergoing off-field screening, compared to non-concussed players (median time 21.1 v 18.4 s, p < 0.01; area under the receiver operating characteristic curve 0.7 (95% CI 0.5-0.8)). Other cognitive measures did not discriminate between injured and un-injured players, with no-statistically significant differences in distribution medians (p = 0.6-0.9) and AUROC values close to 0.5.

CONCLUSIONS

The time taken to perform a modified Stroop Test may provide additional diagnostic accuracy if added to current off-field concussion screening tools. Abridged Spatial Memory and Trail Making Trial-B tests did not discriminate between concussed and non-concussed players.

Sport Concussion Assessment Tool-5th Edition (SCAT5): Normative Reference Values for the National Rugby League Women's Premiership

Objective: To establish normative reference values for the Sport Concussion Assessment Tool-5th Edition (SCAT5) for the new National Rugby League Women's Premiership. Methods: Preseason SCAT5 baseline testing was administered individually to all National Rugby League Women's Premiership players (N = 117). Testing was completed by the medical staff. Normative reference values were calculated for the components of the SCAT5, including the Standardized Assessment of Concussion, modified Balance Error Scoring System, and the Symptom Scale. A small case series of players who sustained concussions were included to illustrate the use of the new normative data. Results: The median Standardized Assessment of Concussion total score was 27.0 (M = 26.9, SD = 2.1). The median modified Balance Error Scoring System score was 2.0 (M = 2.4, SD = 2.2). The median number of symptoms score was 1.0 (M = 3.2, SD = 4.7) and the median symptom severity score was 2.0 (M = 5.4, SD = 8.2). The most common baseline symptom was fatigue or low energy (33%), followed by trouble sleeping (24%), headache (23%), neck pain (22%), and difficulty remembering (21%). In the total sample, 41% reported no symptoms. The clinical interpretation of these new normative data to a case series of women with concussions is provided. Conclusions: Normative reference values are provided for the SCAT5 for women who are professional rugby league players. Using these normative data will improve clinical interpretation of SCAT5 scores following a concussion.

Head injury assessment in rugby union: clinical judgement guidelines

Background/aim

Clinical judgement is a recognised component of a complete off-field concussion assessment. This study identifies guidance criteria for team medical staff when using clinical judgement in their decision-making process during the World Rugby off-field concussion-assessment screen (HIA1).

Methods

Retrospective study of examining doctor clinical judgement in 1149 HIA1 assessments after a meaningful head impact event completed on rugby union players participating in elite-level international and national competitions between September 2015 and June 2018. We assessed (1) an abnormal subtest result as worse performance compared with preseason baseline values; (2) the proportion of cases where clinicians overruled abnormal HIA1 assessment subtest results and (3) made recommendations on how clinical judgement decisions may be made more safely based on the accuracy of clinical judgement decisions assessed against the final concussion diagnosis.

Results

One or more subtests were abnormal compared with baseline values in 857 of 1149 HIA1 assessments. Clinical judgement was used to return players to the game despite abnormal subtest results on 424 out of 857 occasions (49%). In a significant majority of cases 356/424 (84%), clinical judgement decisions were correct, with players later cleared of a concussion. An application of guided clinical judgement potentially decreased false negative assessments by 33% (21/63).

Conclusions

Clinical judgement should be applied in the diagnosis of concussion but done so cautiously. We propose doctors should only use clinical judgement to overrule either one of; or a combination of (1) an abnormal tandem gait and (2) one abnormal cognitive test.

Examining Whether Onfield Motor Incoordination Is Associated With Worse Performance on the SCAT5 and Slower Clinical Recovery Following Concussion

Objective: To examine the relationship between video-identified onfield motor incoordination, the acute assessment of concussion, and recovery time during three seasons of National Rugby League (NRL) play. Methods: Blows to the head ("head impact events") were recorded by sideline video operators and medical staff. Any player with a suspected concussion underwent a Head Injury Assessment in which he was taken off the field and medically evaluated, including the administration of the Sports Concussion Assessment Tool, 5th Edition (SCAT5). Video footage was later examined to determine the presence or absence of onfield motor incoordination following the head impact event. Results: Motor incoordination was identified in 100/1,706 head impact events (5.9%); 65 of the 100 instances of motor incoordination (65.0%) were ultimately medically diagnosed with a concussion. In 646 athletes for whom SCAT5 data were available, those with motor incoordination were more likely to report both dizziness and balance problems than those without motor incoordination, but there were no group differences on an objective balance test. Additionally, there was no relationship between presence/absence of motor incoordination and number of games missed or time to medical clearance for match play. Conclusion: In NRL players, motor incoordination is a readily observable onfield sign that is strongly associated with a medical diagnosis of concussion and with self-reported dizziness/balance problems. However, onfield motor incoordination is not associated with objective balance performance and it is not predictive of time to recover following concussion.

Diagnostic Utility of New SCAT5 Neurological Screen Sub-tests

Background

The Sports Concussion Assessment Tool (SCAT) is recommended to screen for concussion following head impact events in elite sport. The most recent 5th edition (SCAT5) included a ‘rapid neurological screen’ which introduced new subtests examining comprehension, passive neck movement, and diplopia. This study evaluated the additional diagnostic value of these new subtests.

Methods

A prospective cohort study was performed in the Pro14 elite Rugby Union competition between September 2018 and January 2020. The SCAT5 was administered by the team doctor to players undergoing off-field screening for concussion during a medical room assessment. Sensitivity, specificity, false negatives, and positives were examined for SCAT5 comprehension, passive neck movement, and diplopia subtests. The reference standard was a final diagnosis of concussion, established by serial standardised clinical assessments over 48 h.

Results

Ninety-three players undergoing off-field screening for concussion were included. Sensitivity and specificity of the comprehension, passive neck movement, and diplopia subtests were 0, 8, 5% and 0, 91, 97%, respectively (concussion prevalence 63%). No players had any abnormality in comprehension. No players had abnormal passive neck movement or diplopia in the absence of abnormalities in other SCAT5 sub-components.

Conclusions

The new SCAT5 neurological screen subtests are normal in the majority of players undergoing off-field concussion screening and appear to lack diagnostic utility over and above other SCAT5 subtests.

A feasibility study towards instrumentation of the Sport Concussion Assessment Tool (iSCAT)

The Sports Concussion Assessment Tool (SCAT) is a pen and paper-based evaluation tool for use by healthcare professionals in the acute evaluation of suspected concussion. Here we present a feasibility study towards instrumented SCAT (iSCAT). Traditionally, a healthcare professional subjectively counts errors according to SCAT marking criteria matrix. It is hypothesized that an instrumented version of the test will be more accurate while providing additional digital-based parameters to better inform player management. The feasibility study focuses on the SCAT physical functioning tasks only: double leg stance, single-leg stance, tandem stance and tandem gait. Amateur university rugby players underwent iSCAT testing and data were recorded with 8 inertial units attached at different anatomical locations. Video data were gathered simultaneously as reference. An iSCAT algorithm was used to detect errors and quantify additional concussion-based time and frequency domain parameters to assess participant stability during balance and gait tasks. Future work aims to instrument other SCAT features such as hand-eye coordination while deploying methods within a large concussion project.

Effect of a concussion on subsequent baseline SCAT performance in professional rugby players: a retrospective cohort study in global elite Rugby Union

OBJECTIVES

This study assessed whether concussion affects subsequent baseline performance in professional rugby players. Annual baseline screening tests are used to guide return-to-play decisions and concussion diagnosis during subsequent screens. It is important that baseline performances are appropriate and valid for the duration of a season and unaffected by factors unrelated to the current head impact event. One such factor may be a concussion following baseline assessment.

SETTING

The World Rugby concussion management database for global professional Rugby Union.

PARTICIPANTS

501 professional rugby players with two baseline Sports Concussion Assessment Tools (SCATs) and an intervening concussion (CONC) were compared with 1190 control players with successive annual SCAT5s and no diagnosed concussion (CONT).

PRIMARY AND SECONDARY OUTCOME MEASURES

Symptom endorsement, cognitive and balance performance during annual SCAT baseline assessments.

RESULTS

Players with a diagnosed concussion (CONC) endorsed fewer symptoms (change -0.42, 95% CI -0.75 to -0.09), and reported lower symptom severity scores during their second assessment (T2, p<0.001) than non-concussed players (CONT). Concussed players also improved Digits Backward and Final Concentration scores in T2 (p<0.001). Tandem gait time was improved during T2 in CONT. No other sub-mode differences were observed in either group.

CONCLUSIONS

Reduced symptom endorsement and improved cognitive performance after concussion may be the result of differences in the motivation of previously concussed players to avoid exclusion from play, leading to under-reporting of symptoms and greater effort in cognitive tests. Improved cognitive performance may be the result of familiarity with the tests as a result of greater exposure to concussion screening. The changes are small and unlikely to have clinical significance in most cases, though clinicians should be mindful of possible reasons, possibly repeating sub-modes and investigating players whose baseline scores change significantly after concussion. The findings do not necessitate a change in the sport's concussion management policy.