Use of video to facilitate sideline concussion diagnosis and management decision-making

Head Contact and Suspected Concussion Rates in Youth Basketball: Time to Target Head Contact Penalties for Prevention

OBJECTIVE

To compare game events, head contact (HC) rates, and suspected concussion incidence rates (IRs) in boys' and girls' youth basketball.

DESIGN

Cross-sectional.

SETTING

Canadian club basketball teams (U16-U18).

PARTICIPANTS

Players from 24 boys' and 24 girls' Canadian club basketball teams during the 2022 season.

ASSESSMENT OF RISK FACTORS

Recorded games were analyzed using Dartfish video analysis software to compare sexes.

MAIN OUTCOME MEASURES

Poisson regression analyses were used to estimate HCs [direct (HC1) and indirect (HC2)], suspected concussion IRs, and IR ratios (IRRs). Game event, court location, and HC1 fouls were reported.

RESULTS

Division 1 HC rates did not differ between boys (n = 238; IR = 0.50/10 player-minutes; 95% confidence interval [CI], 0.43-0.56) and girls (n = 220; IR = 0.46/10 player-minutes; 95% CI, 0.40-0.52). Division 2 boys experienced 252 HCs (IR = 0.53/10 player-minutes; 95% CI, 0.46-0.59); girls experienced 192 HCs (IR = 0.40/10 player-minutes; 95% CI, 0.35-0.46). Division 2 boys sustained higher HC1 IRs compared with Division 2 girls (IRR = 1.42; 95% CI, 1.15-1.74). Head contacts, rates did not differ between boys and girls in either Division. Suspected concussion IRs were not significantly different for boys and girls in each Division. Head contacts occurred mostly in the key for boys and girls in each Division. Despite illegality, HC1 penalization ranged from 3.9% to 19.7%. Head contact mechanisms varied across Divisions and sexes.

CONCLUSIONS

Despite current safety measures, both HCs and suspected concussions occur in boys' and girls' basketball. Despite the illegality and potential danger associated with HC, only a small proportion of direct HCs were penalized and therefore targeting greater enforcement of these contacts may be a promising prevention target.

Return to Play Following Concussion: Role for Imaging?

This review surveys concussion management, focusing on the use of neuroimaging techniques in return to play (RTP) decisions. Clinical assessments traditionally were the foundation of concussion diagnoses. However, their subjective nature prompted an exploration of neuroimaging modalities to enhance diagnosis and management. Magnetic resonance spectroscopy provides information about metabolic changes and alterations in the absence of structural abnormalities. Diffusion tensor imaging uncovers microstructural changes in white matter. Functional magnetic resonance imaging assesses neuronal activity to reveal changes in cognitive and sensorimotor functions. Positron emission tomography can assess metabolic disturbances using radiotracers, offering insight into the long-term effects of concussions. Vestibulo-ocular dysfunction screening and eye tracking assess vestibular and oculomotor function. Although these neuroimaging techniques demonstrate promise, continued research and standardization are needed before they can be integrated into the clinical setting. This review emphasizes the potential for neuroimaging in enhancing the accuracy of concussion diagnosis and guiding RTP decisions.

On-Field and Pitch-Side (Sideline) Assessment of Sports Concussion in Collision Sports: An Expert Consensus Statement Using the Modified Delphi Technique

PURPOSE

To perform a Delphi consensus for on-field and pitch-side assessment of sports-related concussion (SRC).

METHODS

Open-ended questions in rounds 1 and 2 were answered. The results of the first 2 rounds were used to develop a Likert-style questionnaire for round 3. If agreement at round 3 was ≤80% for an item, if panel members were outside consensus, or there were >30% neither agree/disagree responses, the results were carried forward into round 4. The level of agreement and consensus was defined as 90%.

RESULTS

Loss of consciousness (LOC) or suspected LOC, motor incoordination/ataxia, balance disturbance, confusion/disorientation, memory disturbance/amnesia, blurred vision/light sensitivity, irritability, slurred speech, slow reaction time, lying motionless, dizziness, headaches/pressure in the head, falling to the ground with no protective action, slow to get up after a hit, dazed look, and posturing/seizures were clinical signs of SRC and indicate removal from play. Video assessment is helpful but should not replace clinical judgment. LOC/unresponsiveness, signs of cervical spine injury, suspicion of other fractures (skull/maxillo-facial), seizures, Glasgow Coma Scale score <14 and abnormal neurologic examination findings are indications for hospitalization. Return to play should only be considered when no clinical signs of SRC are present. Every suspected concussion should be referred to an experienced physician.

CONCLUSIONS

Consensus was achieved for 85% of the clinical signs indicating concussion. On-field and pitch-side assessment should include the observation of the mechanism, a clinical examination, and cervical spine assessment. Of the 19 signs and red flags requiring removal from play, consensus was reached for 74%. Normal clinical examination and HIA with no signs of concussion allow return to play. Video assessment should be mandatory for professional games but should not replace clinical decision-making. Sports Concussion Assessment Tool, Glasgow Coma Scale, vestibular/ocular motor screening, Head Injury Assessment Criteria 1, and Maddocks questions are useful tools. Guidelines are helpful for non-health professionals.

LEVEL OF EVIDENCE

Level V, expert opinion.

Characteristics of potential concussive events in elite hurling: a video-analysis study

BACKGROUND

High-impact sports such as hurling place participants at risk of sport-related concussion (SRC).

AIMS

This study will evaluate the characteristics of potential concussive events (PCEs) that occur in elite male hurling to acquire an understanding of how they occur.

METHODS

The authors recorded PCEs and their characteristics throughout two seasons of inter-county GAA competition using broadcast footage based on a previously validated protocol.

RESULTS

A total of 183 PCEs were identified over 82 inter-county matches (2.23 per match; 59.5 per 1000 h of exposure). PCEs that occurred in the 4th quarter were significantly more likely to result in signs of SRC. Players most often intended to receive/control the sliotar (36.4%, n = 64) prior to PCEs. The most frequently observed mechanism was shoulder-to-head (20.2%, n = 37). Impacts to the lateral aspect of the head were 2.7 times more likely to result in visible signs than impacts to anteroposterior regions.

CONCLUSIONS

Players appear to be at a higher risk of SRC later in the match or when receiving the sliotar. Strikes to the lateral aspect of the head and those involving the shoulder appear to produce severe events. These findings provide initial guidance for the development of targeted player protection strategies.

Validation of an instrumented mouthguard in rugby union-a pilot study comparing impact sensor technology to video analysis

Background

To better understand the biomechanical profile of direct head impacts and the game scenarios in which they occur in Rugby Union, there is a need for an on-field validation of a new instrumented mouthguard (IMG) against the reference standard. This study considers the potential of a combined biomechanical (IMG) and video analysis approach to direct head impact recognition, both of which in isolation have limitations. The aim of this study is to assess the relationship between an instrumented mouthguard and video analysis in detection of direct head impacts in rugby union.

Design

Pilot Study - Observational Cohort design.

Methods

The instrumented mouthguard was worn by ten (3 backs, 7 forwards) professional Rugby Union players during the 2020-21 Gallagher Premiership (UK) season. Game-day video was synchronized with timestamped head acceleration events captured from the instrumented mouthguard. Direct Head Impacts were recorded in a 2 × 2 contingency table to determine sensitivity. Impact characteristics were also collected for all verified head impacts to further the understanding of head biomechanics during the game.

Results

There were 2018 contact events that were reviewed using video analysis. Of those 655 were categorized as direct head impacts which also correlated with a head acceleration event captured by the IMG. Sensitivity analysis showed an overall sensitivity of 93.6% and a positive predictive value (PPV of 92.4%). When false positives were excluded due to ball out of play, mouthguard removal or handling after a scoring situation or stoppage, PPV was improved (98.3%). Most verified head impacts occurred in and around the ruck contest (31.2%) followed by impacts to the primary tackler (28.4%).

Conclusion

This pilot validation study demonstrates that this IMG provides a highly accurate measurement device that could be used to complement video verification in the recognition of on-field direct head impacts. The frequency and magnitude of direct head impacts derived from specific game scenarios has been described and allows for greater recognition of high-risk situations. Further studies with larger sample sizes and in different populations of Rugby Union players are required to develop our understanding of head impact and enable strategies for injury mitigation.

A case-control study of tackle based head impact event (HIE) risk factors from the first three seasons of the National Rugby League Women's competition

Objective

The tackle is the most injurious event in rugby league and carries the greatest risk of concussion. This study aims to replicate previous research conducted in professional men's rugby league by examining the association between selected tackle characteristics and head impact events (HIEs) in women's professional rugby league.

Methods

We reviewed and coded 83 tackles resulting in an HIE and every tackle (6,318 tackles) that did not result in an HIE for three seasons (2018-2020) of the National Rugby League Women's (NRLW) competition. Tackle height, body position of the tackler and ball carrier, as well as the location of head contact with the other player's body were evaluated. Propensity of each situation that caused an HIE was calculated as HIEs per 1,000 tackles.

Results

The propensity for tacklers to sustain an HIE was 6.60 per 1,000 tackles (95% CI: 4.87-8.92), similar to that of the ball carrier (6.13 per 1,000 tackles, 95% CI: 4.48-8.38). The greatest risk of an HIE to either the tackler or ball carrier occurred when head proximity was above the sternum (21.66 per 1,000 tackles, 95% CI: 16.55-28.35). HIEs were most common following impacts between two heads (287.23 HIEs per 1,000 tackles, 95% CI: 196.98-418.84). The lowest propensity for both tackler (2.65 per 1,000 tackles, 95% CI: 0.85-8.20) and ball carrier HIEs (1.77 per 1,000 tackles, 95% CI: 0.44-7.06) occurred when the head was in proximity to the opponent's shoulder and arm. No body position (upright, bent or unbalanced/off feet) was associated with an increased propensity of HIE to either tackler or ball carrier.

Conclusions

In the NRLW competition, tacklers and ball carriers have a similar risk of sustaining an HIE during a tackle, differing from men's NRL players, where tacklers have a higher risk of HIEs. Further studies involving larger samples need to validate these findings. However, our results indicate that injury prevention initiatives in women's rugby league should focus on how the ball carrier engages in contact during the tackle as well as how the tackler executes the tackle.

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.

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.

Observable player behaviours and playing performance following helmet strikes in elite cricket

OBJECTIVES

Investigate the observable player behaviours and features of both concussive (HS-C) and non-concussive (HS-NC) helmet strikes and describe their impact on playing performance.

METHODS

Elite male cricketers sustaining helmet strikes between the 2016 and 2018 seasons were identified by the England and Wales Cricket Board. Medical records identified players sustaining a concussion and those in whom concussion was excluded. Retrospective cohort analysis was performed on batting and bowling performance data available for these players in the 2 years prior to and 3 months post helmet strike. Video analysis of available incidents was conducted to describe the characteristics of the helmet strike and subsequent observable player behaviours. The HS-C and HS-NC cohorts were compared.

RESULTS

Data were available for 194 helmet strikes. 56 (29%) resulted in concussion. No significant differences were seen in playing performance in the 3 months post concussive helmet strike. However, a significant decline in batting performance was seen in this period in the HS-NC group (p<0.001).Video features signifying motor incoordination were most useful in identifying concussion post helmet strike, however, typical features suggesting transient loss of consciousness were not seen. Features such as a longer duration pause prior to the batsman resuming play and the level of concern shown by other players were also useful features.

CONCLUSION

HS-NC may be more significant for player performance than previously thought. Guidance for using video replay to identify concussion in cricket may need to be modified when compared with other field sports.

The association of padded headgear with concussion and injury risk in junior Australian football: A prospective cohort study

OBJECTIVES

To assess whether padded headgear was associated with incidence of suspected sports-related concussion, non-sports-related concussion head injury, and injuries to other body regions in junior Australian football.

DESIGN

Prospective cohort injury surveillance.

METHODS

There were 400 junior players (42.5% female) enrolled across two seasons. Suspected sports-related concussion was defined by detection of observable signs on the field and medical assessment or missed match(es) due to suspected sports-related concussion. Non-sports-related concussion head injury and injuries to other body regions were defined as those that received medical assessment or resulted in a missed match.

RESULTS

There were 20 teams monitored over 258 matches. 204 players (2484 player hours) wore mandated headgear throughout the season and 196 (2246 player hours) did not. The incidence rate of suspected sports-related concussion was 3.17 (95% confidence interval: 3.04-3.30) per 1000 player-hours and no differences were observed between males and females (risk ratio 1.11; 95% confidence interval: 0.40-3.06). Headgear use was not associated with suspected sports-related concussion (risk ratio 1.09; 95% confidence interval: 0.41-2.97), non-sports-related concussion head injury (risk ratio 0.27; 95% confidence interval: 0.06-1.31), or injuries to other body regions (risk ratio 1.41; 95% confidence interval: 0.79-2.53).

CONCLUSIONS

Headgear use was not associated with reduced risk of suspected sports-related concussion, non-sports-related concussion head injury or injuries to other body regions. There was no difference in the rate of suspected sports-related concussion in female compared to male players, however, rates of non-sports-related concussion head injury and injuries to other body regions were higher in male players.

Concussion occurrence and recognition in professional boxing and MMA matches: toward a concussion protocol in combat sports

Objectives: Determine, through video reviews, how often concussions occur in combat sport matches, what influence they have on the outcome, and how well non-physician personnel can be trained to recognize concussions.Methods: This is a retrospective video analysis by an 8-person panel of 60 professional fights (30 boxing and 30 mixed martial arts). Through video review, physician and non-physician personnel recorded details about each probable concussion and determined if and when they would have stopped the fight compared to the official stoppage time.Results: A concussion was recorded in 47/60 fights. The mean number of concussions per minute of fight time was 0.061 (0.047 for boxers and 0.085 for MMA). When stratifying by outcome of the bout, the mean number of concussions per minute for the winner was 0.010 compared to the loser at 0.111 concussions per minute. The fighter that sustained the first concussion ultimately lost 98% of the time. The physician and non-physician raters had high agreement regarding the number of concussions that occurred to each fighter per match. The physician raters judged that 24 of the 60 fights (11 boxing [37%]; 13 MMA [43%]) should have been stopped sooner than what occurred.Conclusion: Recognizing that the concussions often occur in combat sport matches, that the losing fighter almost always is concussed first and tends to sustain more concussions during the fight, along with the demonstration that non-physician personnel can be taught to recognize concussion, may guide policy changes that improve brain health in combat sports.

Video analysis of potential concussions in elite male Hurling: are players being assessed according to league guidelines?

Background

Hurling is a fast-paced contact sport that places players at risk of concussion. Given the consequences of repeated concussive impacts, it is imperative that concussion management guidelines are followed.

Hypothesis/Purpose.

The aim of this study is to determine if potential concussive events (PCEs) in elite Hurling are assessed in accordance with league management guidelines. The secondary objective is to investigate the effectiveness of current concussion training programs.

Methods

Investigators used a video analysis approach to identify PCEs throughout the 2018 and 2019 inter-county Hurling seasons and championships. Subsequent assessment, return to play (RTP) decision, and signs of concussion were evaluated based on previously validated methods. The results were then compared year-over-year with previous research in Gaelic Football (GF).

Results

A total of 183 PCEs were identified over 82 matches. PCEs were frequently assessed (86.3%, n = 158) by medical personnel. The majority of assessments were less than 1 min in duration (81.0%, n = 128). Thirteen (7.1%) players were removed following a PCE. There were 43 (23.5%) PCEs that resulted in one or more signs of concussion, of which 10 (23.3%) were removed from play. There was no difference in rate of assessment, duration of assessment, or rate of RTP between 2018 and 2019 in both Hurling and GF, suggesting that current concussion training programs have had limited success.

Conclusion

In Hurling, players suspected of having sustained a concussion are frequently subject to a brief assessment, and are rarely removed from play. Affirmative action is needed to ensure the consistent application of standardized concussion assessment across the Gaelic Games.

Characteristics of potential concussive events in elite male gaelic football players: A descriptive video-analysis

Gaelic football (GF) is a high-impact sport and Sport-Related Concussion (SRC) is an issue within the game. Our aim was to evaluate the characteristics of Potential Concussive Events (PCEs) that occur in the Gaelic Athletic Association National Football League and extrapolate this data to reduce the incidence and severity of SRC. PCEs may or may not lead to a clinical diagnosis of SRC, but represent high-risk events and therefore may be a useful indicator. A video-analysis approach was undertaken to identify PCEs throughout two seasons of play using broadcast footage, and characteristics of each PCE were measured based on previously validated methods. A total of 242 PCEs were identified over 111 matches (2.18 per match, 58.14 per 1000 hours of exposure). PCEs were frequently not anticipated by the player (40.5%, n = 98). The most common impact locations were the mandibular region (33.1%, n = 80) and the temporal region (21.1%, n = 51), and the most frequently observed mechanism was hand/fist to head (27.3%, n = 66). A second-hit was observed in 34 PCEs (14.0%). The findings provide initial guidance for the development of player protection strategies to reduce the incidence and severity of SRC in Gaelic Football.

Reliability of Using the Proposed International Consensus Video Signs of Potential Concussion for National Rugby League Head Impact Events

BACKGROUND

Consensus on the definition of extant video signs of concussion have recently been proposed by representatives of international sporting codes for global consistency across professional leagues.

OBJECTIVE

To review the reliability of the proposed international consensus video signs of concussion in National Rugby League (NRL) head impact events (HIEs).

METHODS

The video signs of concussion were coded for every HIE during the 2019 NRL season. Coding was conducted blinded to the concussion status. Frequency, sensitivity, specificity, and a receiver operating characteristic curve were calculated.

RESULTS

There were 943 HIEs identified over the 2019 NRL season, of which 106 resulted in a diagnosed concussion. The most frequently observed video sign in concussed athletes was blank/vacant look (54%), which was also the most sensitive video sign (0.54, CI: 0.44-0.63), while the most specific was tonic posturing (0.99, CI: 0.99-1.00). In 43.4% of diagnosed concussions none of the 6 video signs were present. The 6 video signs demonstrated a "fair" ability to discriminate between concussion and nonconcussion HIEs (area under the curve = 0.76).

CONCLUSION

International consensus agreement between collision sports for extant video signs of concussion and the definition of those extant video signs are clinically important. The selection of signs requires rigorous assessment to examine their predictive value across all sports and within individual sports, and to determine further video signs to compliment and improve the identification of possible concussion events within various sports. The current study demonstrated that, for NRL-related HIEs, the diagnostic accuracy of video signs varies.

Are you missing a concussion by watching American football? Video analysis of ball location in a Division 1 football program

OBJECTIVE

Action in a football game occurs quickly. Medical staff can miss a sport-related concussion (SRC) if they do not observe it directly. The objective of this study is to determine if SRCs occur more frequently at ball than away from ball during gameplay. Game-specific concussion statistics can enhance medical provider care of athletes.

METHODS

We used gameplay videos of an NCAA Division I football program to analyze SRCs and determine the primary tackler or ball handler during each concussion play. We compared the relative risk of SRCs for the primary ball handlers/tacklers to that of the other 10 players on the same team during that play.

RESULTS

Over 10 seasons, 26 SRCs occurred at ball for the primary ball handler/tackler position (0.22 SRCs/game) versus 16 away from ball (0.13 SRCs/game). The relative risk of an SRC according to exposure (at ball) vs. no exposure (away from ball) was 16.2 (CI 8.7-30.2, P < .05). Special teams had more SRCs away from ball than at ball, but this was not significant (relative risk 3.32, CI 0.90-12.3, P > .05).

CONCLUSIONS

The study provides medical staff guidance to more efficiently identify in-game SRCs and supports evidence for rules changes.

Visible Signs of Concussion and Cognitive Screening in Community Sports

Video surveillance and detection of players with visible signs of concussion by experienced medical staff facilitates rapid on-field screening of suspected concussion in professional sports. This method, however has not been validated in community sports where video footage is unavailable. This study aimed to explore the utility of visible signs of concussion to identify players with decrements in performance on concussion screening measures. In this observational prospective cohort study, personnel with basic training observed live matches across a season (60 matches) of community male and female Australian football for signs of concussion outlined in the community-based Head Injury Assessment form (HIAf). Players identified to have positive signs of concussion (CoSign+) following an impact were compared with players without signs (CoSign-). Outcome measures, the Sport Concussion Assessment Tool (SCAT3) and Cogstate, were administered at baseline and post-match. CoSign+ (n = 22) and CoSign- (n = 61) groups were similar with respect to age, sex, education, baseline mood, and medical history. CoSign+ players exhibited worse orientation, concentration, and recall, and slower reaction time in attention and working memory tasks. Comparing individual change from baseline to post-match assessment revealed 100% (95% confidence interval [CI]: 84-100%) of CoSign+ players demonstrated clinically significant deficits on SCAT3 or Cogstate tasks, compared with 59% (95% CI: 46-71%) of CoSign- players. All CoSign+ players observed to have a blank/vacant look demonstrated clinically significant decline on the Standardized Assessment of Concussion (SAC). Detection of visible signs of concussion represents a rapid, real-time method for screening players suspected of concussion in community sports where video technology and medical personnel are rarely present. Consistent with community guidelines, it is recommended that all CoSign+ players be immediately removed from play for further concussion screening.

Concussions in the National Football League: the evolution of video review for assessing the frequency and reliability of visible signs

Background: The use of video review to document visible signs (VS) of sport-related concussion in the National Football League (NFL) is a novel method to recognize head injuries. Hypothesis/Purpose: The current pilot studies used varying methodologies to (1) examine the frequency of VS in concussed NFL players using the Australian Football League's (AFL) checklist, and (2) assess the reliability of VS between non-expert and expert raters. Study design: Cohort study Methods: In the first pilot study, two non-expert raters rated VS of SRC occurring in the 2015 NFL season (n = 96) using a single VS from the AFL checklist. Based on this pilot study, two expert raters then rated VS of SRC during the 2017 NFL season (n = 211) using all VS from the AFL checklist. The frequency, total percent agreement (TPA), and reliability (kappa coefficients) were calculated for all VS of concussion for the two seasons. Kappa agreement was classified as fair (.41-.60), moderate (.61-.80), or substantial (.81-1.00). Significance was set at p < .05. Results: The most frequent VS of concussion identified by both non-expert and expert raters were no behavior observed, slow to get up, and motor incoordination. The least frequent VS were impact seizure, blank/vacant look, and facial injury. For non-expert raters, the average TPA for VS ranged from 84% to 100% and kappa coefficients ranged from .52 to .68. For expert raters, the average TPA ranged from 83% to 100%, and kappa coefficients ranged from .56 to .86. Conclusion: In these preliminary analyses, use of multiple VS was a superior methodology, and the reliability of VS rating was stronger for experts. Due to the inherent differences in gameplay and protective equipment used in the NFL compared to other professional sports, it is our hope these data can generate new ways to improve existing practices and identify potentially novel VS of SRC.

Frequent but limited assessment of potentially concussed players in Gaelic Football: an opportunity to learn from other sports

BACKGROUND

Sport-related concussion (SRC) is a potential issue within Gaelic Football. Therefore, it is essential that concussion management guidelines are adhered to.

HYPOTHESIS/PURPOSE

The aim of this study is to determine if potential concussive events (PCEs) in the Gaelic Athletic Association (GAA) National Football League (NFL) are assessed in accordance with GAA concussion guidelines and compare this to other sports.

METHODS

A descriptive video analysis approach was undertaken to identify PCEs throughout two seasons of play. Subsequent assessment, return to play (RTP) decisions, and signs of concussion were evaluated.

RESULTS

A total of 242 PCEs were identified over 111 matches. Most PCEs (87.2%, n = 211) were assessed by medical personnel. However, 187 (88.6%) of assessments were under 2 min in duration. Of the 242 PCEs, 189 (78.1%) returned to play after on-pitch assessment, and 12 (5.0%) were removed following a PCE. Sixty-one (25.2%) players sustaining a PCE demonstrated one or more signs of concussion, of which 9 (14.8%) were removed from play.

CONCLUSION

In the GAA NFL, PCEs are often briefly assessed but rarely result in player removal. Introduction of video incident analysis and concussion substitutions, as in other sports, may reduce the long-term burden of SRC on Gaelic Football players.

Sensitivity and Specificity of On-Field Visible Signs of Concussion in the National Football League

BACKGROUND

On-field visible signs (VS) are used to help identify sport-related concussion (SRC) in the National Football League (NFL). However, the predictive utility of a VS checklist for SRC is unknown.

OBJECTIVE

To report the frequency, sensitivity, specificity, and predictive value of VS in a cohort of NFL athletes.

METHODS

On-field VS ratings from 2 experts who independently reviewed video footage of a cohort of 251 injury plays that resulted in an SRC diagnosis (n = 211) and no diagnosis (n = 40) from the 2017 NFL season were examined. The frequency, sensitivity, specificity, and a receiver operating characteristic (ROC) curve with area under the curve (AUC) were calculated for each VS.

RESULTS

Slow to get up (65.9%) and motor incoordination (28.4%) were the most frequent VS in concussed athletes, and slow to get up (60.0%) was the most common VS among nonconcussed athletes. The most sensitive VS was slow to get up (66%); the most specific signs in concussed NFL athletes were blank/vacant look and impact seizure (both 100%). Approximately 26% of concussed NFL players did not exhibit a VS, and the overall sensitivity and specificity for the VS checklist to detect SRC were 73% and 65%, respectively. The VS checklist demonstrated “poor” ability to discriminate between SRC and non-SRC groups (AUC = 0.66).

CONCLUSION

In the NFL, the diagnosis of concussion cannot be made from on-field VS alone. The VS checklist is one part of the comprehensive sideline/acute evaluation of concussion, and the diagnosis remains a multimodal clinical decision.

Video Analysis of Concussion Exposures in a National Collegiate Athletic Association Division I Football Team

Background:

Research into improving player safety of sport-related concussion (SRC) in American football has been an ongoing endeavor. In an attempt to better understand the incidence of SRCs in American football, research has focused on the characteristics of SRC during gameplay. Determining SRC specifics and assessing them quantitatively can help identify high-risk scenarios and predict exposure risk.

Purpose:

To identify and assess the incidence of SRCs in a National Collegiate Athletic Association football team by comparing field location, player positions, collision partners, and player cues.

Study Design:

Descriptive epidemiology study.

Methods:

We used physician sideline reports of diagnosed concussions from a Division I football team from September 2010 to December 2018. Game videos were analyzed to identify the field location where the SRC occurred, collision partner, and player behavior postconcussion. The incidence of in-game SRCs by position was also assessed. We used the “words of estimative probability” model to categorize each concussion as certain, almost certain, probable, or even on the basis of our confidence in identifying them using game film.

Results:

This study examined 44 SRCs that occurred over 9 seasons. The SRC incidence was significantly higher in the middle defense (5-20 yards from the line of scrimmage) compared with all other field locations (relative risk, 2.46; 95% CI, 1.14-5.29; P < .05). In-game collision partners were most commonly defensive backs. The most common player cue was a hand to helmet/face mask. The positions with the highest SRC incidence by athlete-exposure, game position, and position play belonged to the defensive backs, wide receivers, and running backs.

Conclusion:

The middle defense had a significantly higher incidence of SRCs than all other field locations. We pose a new method to categorize concussions during video analysis by using words of estimative probability. Knowledge of SRC gameplay characteristics can potentially guide the medical staff and medical observer to better identify them.

International consensus definitions of video signs of concussion in professional sports

BACKGROUND

The use of video to assist professional sporting bodies with the diagnosis of sport-related concussion (SRC) has been well established; however, there has been little consistency across sporting codes with regards to which video signs should be used, and the definitions of each of these signs.

AIM

The aims of this study were to develop a consensus for the video signs considered to be most useful in the identification of a possible SRC and to develop a consensus definition for each of these video signs across the sporting codes.

METHODS

A brief questionnaire was used to assess which video signs were considered to be most useful in the identification of a possible concussion. Consensus was defined as >90% agreement by respondents. Existing definitions of these video signs from individual sports were collated, and individual components of the definitions were assessed and ranked. A modified Delphi approach was then used to create a consensus definition for each of the video signs.

RESULTS

Respondents representing seven sporting bodies (Australian Football League, Cricket Australia, Major League Baseball, NFL, NHL, National Rugby League, World Rugby) reached consensus on eight video signs of concussion. Thirteen representatives from the seven professional sports ranked the definition components. Consolidation and refinement of the video signs and their definitions resulted in consensus definitions for six video signs of possible concussion: lying motionless, motor incoordination, impact seizure, tonic posturing, no protective action-floppy and blank/vacant look.

CONCLUSIONS

These video signs and definitions have reached international consensus, are indicated for use by professional sporting bodies and will form the basis for further collaborative research.

Verifying Head Impacts Recorded by a Wearable Sensor using Video Footage in Rugby League: a Preliminary Study

BACKGROUND

Rugby league is a full-contact collision sport with an inherent risk of concussion. Wearable instrumented technology was used to observe and characterize the level of exposure to head impacts during game play.

PURPOSE

To verify the impacts recorded by the x-patch™ with video analysis.

STUDY DESIGN

Observational case series.

METHODS

The x-patch™ was used on eight men's semi-professional rugby league players during the 2016 Newcastle Rugby League competition (five forwards and three backs). Game day footage was recorded by a trained videographer using a single camera located at the highest midfield location to verify the impact recorded by the x-patch™. Videographic and accelerometer data were time synchronized.

RESULTS

The x-patch™ sensors recorded a total of 779 impacts ≥ 20 g during the games, of which 732 (94.0%) were verified on video. In addition, 817 impacts were identified on video that did not record an impact on the sensors. The number of video-verified impacts ≥ 20 g, per playing hour, was 7.8 for forwards and 4.8 for backs (range = 3.9-19.0). Impacts resulting in a diagnosed concussion had much greater peak linear acceleration (M = 76.1 g, SD = 17.0) than impacts that did not result in a concussion (M = 34.2g, SD = 18.0; Cohen's d = 2.4).

CONCLUSIONS

The vast majority (94%) of impacts ≥ 20 g captured by the x-patch™ sensor were video verified in semi-professional rugby league games. The use of a secondary source of information to verify impact events recorded by wearable sensors is beneficial in clarifying game events and exposure levels.

Video Analysis of Reported Concussion Events in the National Football League During the 2015-2016 and 2016-2017 Seasons

BACKGROUND

Concussions in American football remain a high priority of sports injury prevention programs. Detailed video review provides important information on causation, the outcomes of rule changes, and guidance on future injury prevention strategies.

PURPOSE

Documentation of concussions sustained in National Football League games played during the 2015-2016 and 2016-2017 seasons, including consideration of video views unavailable to the public.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

All reported concussions were reviewed with all available video footage. Standardized terminology and associated definitions were developed to describe and categorize the details of each concussion.

RESULTS

Cornerbacks sustained the most concussions, followed by wide receivers, then linebackers and offensive linemen. Half (50%) of concussions occurred during a passing play, 28% during a rushing play, and 21% on a punt or kickoff. Tackling was found to be the most common activity of concussed players, with the side of the helmet the most common helmet impact location. The distribution of helmet impact source-the object that contacted the concussed player's helmet-differed from studies of earlier seasons, with a higher proportion of helmet-to-body impacts (particularly shoulder) and helmet-to-ground impacts and with a lower proportion of helmet-to-helmet impacts. Helmet-to-ground concussive impacts were notable for the high prevalence of impacts to the back of the helmet and their frequency during passing plays.

CONCLUSION

Concussion causation scenarios in the National Football League have changed over time.

CLINICAL RELEVANCE

The results of this study suggest the need for expanded evaluation of concussion countermeasures beyond solely helmet-to-helmet test systems, including consideration of impacts with the ground and with the body of the opposing player. It also suggests the possibility of position-specific countermeasures as part of an ongoing effort to improve safety.

International study of video review of concussion in professional sports

Background

Video review has become an important tool in professional sporting codes to help sideline identification and management of players with a potential concussion.

Aim

To assess current practices related to video review of concussion in professional sports internationally, and compare protocols and diagnostic criteria used to identify and manage potential concussions.

Methods

Current concussion management guidelines from professional national and international sporting codes were reviewed. Specific criteria and definitions of video signs associated with concussion were compared between codes. Rules and regulations adopted across the codes for processes around video review were also assessed.

Results

Six sports with specific diagnostic criteria and definitions for signs of concussion identified on video review participated in this study (Australian football, American football, world rugby, cricket, rugby league and ice hockey). Video signs common to all sports include lying motionless/loss of responsiveness and motor incoordination. The video signs considered by the majority of sports as most predictive of a diagnosis of concussion include motor incoordination, impact seizure, tonic posturing and lying motionless. Regulatory requirements, sideline availability of video, medical expertise of video reviewers and use of spotters differ across sports and geographical boundaries. By and large, these differences reflect a pragmatic approach from each sport, with limited underlying research and development of the video review process in some instances.

Conclusions

The use of video analysis in assisting medical staff with the diagnosis or identification of potential concussion is well established across different sports internationally. The diagnostic criteria used and the expertise of the video review personnel are not clearly established, and research efforts would benefit from a collaborative harmonisation across sporting codes.

The Use of Sideline Video Review to Facilitate Management Decisions Following Head Trauma in Super Rugby

Background

Sideline video review has been increasingly used to evaluate risk of concussive injury during match play of a number of collision sports, with the view to reducing the incidence of match play concussion injuries. The purpose of this study was to evaluate the effectiveness of sideline video review for identifying and evaluating head impact events in Rugby Union.

Methods

All Australian teams’ 2015 Super Rugby season matches were studied. Meaningful head impact events (HIEs) were identified, comprising events identified and acted upon during matches and events identified through a post-season retrospective review. Video footage of each HIE was coded by two experienced independent sports medicine clinicians to evaluate management decisions made by match-day (MDD) and team doctors (TD). HIE incidences for matches with and without sideline video were compared, and the agreement between game-day video interpretation and the independent clinician opinion calculated.

Results

Seventy HIEs were identified in 83 matches (47 identified during matches and 23 identified post-season), equating to 42.5 HIEs per 1000 player match hours. When video review was available, an unnoticed HIE occurred once every 4.3 matches, compared to once every 2.3 matches when the sideline video review was unavailable. Of the 47 identified in-match HIEs evaluated by TD and MDD during the season, 18 resulted in an immediate and permanent removal, 28 resulted in temporary removal for an off-field assessment, and one resulted in the player continuing the game. Game-day head injury assessment process video decisions agreed with the independent clinician view in 72% of cases, κ = 0.49 (95% CI 0.38–0.59, weak agreement).

Conclusions

These findings suggest that access to sideline video review is an important supplementary component to identify potential concussions; however, there is a critical need for improved systems and processes to reduce the likelihood of missing an incident.

A video review of multiple concussion signs in National Rugby League match play

BACKGROUND

Video review has been introduced in many professional sports worldwide to help recognize concussions. However, to date, there has been very little research on the accuracy of using video analysis to identify signs of concussion and the various combinations of observed signs.

METHODS

The objective of the study is to determine the accuracy of combinations of clinical signs of concussion identified using video analysis to identify concussions in the National Rugby League (NRL). Incidences of players using of the concussion interchange rule (CIR) (n = 156), including those where athletes were diagnosed with a concussion (n = 60), were used to calculate sensitivity and specificity of various combinations of concussion signs (unresponsiveness, slow to get up, clutching/shaking head, gait ataxia, vacant stare, and apparent seizure) and their independent association with an eventual diagnosis of concussion.

RESULTS

Using video analysis, players who were diagnosed with a concussion showed a significantly greater total number of signs at the time of injury (mean = 3.4, SD = 1.3) than those who were removed from play but not diagnosed with a concussion (mean = 3.0, SD = 0.9 signs; p = .046). Players who did not return to play during the same game demonstrated a significantly greater number of total signs than those who did return to play in the same game following CIR activation (mean = 3.4, SD = 1.2 versus mean = 2.9, SD = 0.9; p = 0.002). The most common combination of signs that was observed was clutching/shaking the head and slowness in getting up (17.3%). The sensitivity of the total number of signs observed decreased as the number of signs increased (range = 0.13-0.62), while the specificity increased as more signs were observed (range = 0.29-0.90). Most of the combinations of different observed signs at the time of potential injury were highly specific (> 0.80), but not sensitive to an eventual diagnosis of concussion. When considering all potential predictor variables in a logistic regression model, anticipating the oncoming collision (OR = 3.92, 95% CI = 1.28-12.03), fewer number of defenders involved in the tackle (OR = 0.58, 95% CI = 0.36-0.92), and the presence of a blank or vacant stare (OR = 2.97, 95% CI = 1.26-7.01) were each significantly associated with concussion diagnoses.

CONCLUSIONS

The use of video review in the NRL is challenging, but being aware of the combinations of possible concussion signs and the likelihood that various presentations result in a concussion diagnosis can provide a useful addition to sideline concussion identification and removal from play decisions.

Evidence of Concussion Signs in National Rugby League Match Play: a Video Review and Validation Study

BACKGROUND

Many professional sports have introduced sideline video review to help recognise concussions. The reliability and validity of identifying clinical and observable signs of concussion using video analysis has not been extensively explored. This study examined the reliability and validity of clinical signs of concussion using video analysis in the National Rugby League (NRL).

METHODS

All 201 professional NRL matches from the 2014 season were reviewed to document six signs of possible concussion (unresponsiveness, slow to get up, clutching/shaking head, gait ataxia, vacant stare, and seizure).

RESULTS

A total of 127,062 tackles were reviewed. Getting up slowly was the most common observable sign (2240 times in the season, 1.8% of all tackles) but only 223 times where it appeared to be a possible concussion (0.2% of all tackles and 10.0% of the times it occurred). Additionally, clutching/shaking the head occurred 361 times (on 212 occasions this sign appeared to be due to a possible concussion), gait ataxia was observed 102 times, a vacant stare was noted 98 times, unresponsiveness 52 times, and a possible seizure 4 times. On 383 occasions, one or more of the observable signs were identified and deemed associated with a possible concussion. There were 175 incidences in which a player appeared to demonstrate two or more concussion signs, and 54 incidences where a player appeared to demonstrate three or more concussion signs. A total of 60 diagnosed concussions occurred, and the concussion interchange rule was activated 167 times. Intra-rater reliability (κ = 0.65-1.00) was moderate to perfect for all six video signs; however, the inter-rater reliability was not as strong (κ = 0.22-0.76). Most of the signs had relatively low sensitivity (0.18-0.75), but high specificity (0.85-1.00).

CONCLUSIONS

Using video replay, observable signs of concussion appear to be sensitive to concussion diagnoses when reviewing known injuries among professional rugby league players. When reviewing an entire season, however, certain signs occur very commonly and did not identify concussion. Thus, the implementation of video review in the NRL is challenging, but can provide a useful addition to sideline concussion identification and removal from play decisions.

Injuries in Australian Rules Football: An Overview of Injury Rates, Patterns, and Mechanisms Across All Levels of Play

CONTEXT

The nature of Australian rules football (Australian football) predisposes both unique and common injuries compared with those sustained in other football codes. The game involves a combination of tackling, kicking, high-speed running (more than other football codes), and jumping. Two decades of injury surveillance has identified common injuries at the professional level (Australian Football League [AFL]).

OBJECTIVE

To provide an overview of injuries in Australian rules football, including injury rates, patterns, and mechanisms across all levels of play.

STUDY DESIGN

A narrative review of AFL injuries, football injury epidemiology, and biomechanical and physiological attributes of relevant injuries.

RESULTS

The overall injury incidence in the 2015 season was 41.7 injuries per club per season, with a prevalence of 156.2 missed games per club per season. Lower limb injuries are most prevalent, with hamstring strains accounting for 19.1 missed games per club per season. Hamstring strains relate to the volume of high-speed running required in addition to at times having to collect the ball while running in a position of hip flexion and knee extension. Anterior cruciate ligament injuries are also prevalent and can result from contact and noncontact incidents. In the upper limb, shoulder sprains and dislocations account for 11.5 missed games per club per season and largely resulted from tackling and contact. Concussion is less common in AFL than other tackling sports but remains an important injury, which has notably become more prevalent in recent years, theorized to be due to a more conservative approach to management. Although there are less injury surveillance data for non-AFL players (women, community-level, children), many of these injuries appear to also be common across all levels of play.

CLINICAL RELEVANCE

An understanding of injury profiles and mechanisms in Australian football is crucial in identifying methods to reduce injury risk and prepare players for the demands of the game.

Observational Review and Analysis of Concussion: a Method for Conducting a Standardized Video Analysis of Concussion in Rugby League

Background

Several professional contact and collision sports have recently introduced the use of sideline video review for club medical staff to help identify and manage concussions. As such, reviewing video footage on the sideline has become increasingly relied upon to assist with improving the identification of possible injury. However, as yet, a standardized method for reviewing such video footage in rugby league has not been published. The aim of this study is to evaluate whether independent raters reliably agreed on the injury characterization when using a standardized observational instrument to record video footage of National Rugby League (NRL) concussions.

Methods

Video footage of 25 concussions were randomly selected from a pool of 80 medically diagnosed concussions from the 2013–2014 NRL seasons. Four raters (two naïve and two expert) independently viewed video footage of 25 NRL concussions and completed the Observational Review and Analysis of Concussion form for the purpose of this inter-rater reliability study. The inter-rater reliability was calculated using Cohen’s kappa (κ) and intra-class correlation (ICC) statistics. The two naïve raters and the two expert raters were compared with one another separately.

Results

A considerable number of components for the naïve and expert raters had almost perfect agreement (κ or ICC value ≥ 0.9), 9 of 22 (41%) components for naïve raters and 21 of 22 (95%) components for expert raters. For the concussion signs, however, the majority of the rating agreement was moderate (κ value 0.6–0.79); both the naïve and expert raters had 4 of 6 (67%) concussion signs with moderate agreement. The most difficult concussion sign to achieve agreement on was blank or vacant stare, which had weak (κ value 0.4–0.59) agreement for both naïve and expert raters.

Conclusions

There appears to be value in expert raters, but less value for naive raters, in using the new Observational Review and Analysis of Concussion (ORAC) Form. The ORAC Form has high inter-rater agreement for most data elements, and it can be used by expert raters evaluating video footage of possible concussion in the NRL.