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

BACKGROUND: The extent of concussion injury in the rugby codes for women is unclear. OBJECTIVE: Our aim was to review all published studies reporting concussion injuries from match and training participation in rugby codes and report the pooled data estimates for rugby league and union concussion injury epidemiology. METHODS: We conducted a systematic literature analysis of concussion in rugby league and rugby union for published studies from January 1990 to July 2021. Data from 16 studies meeting the inclusion criteria were extracted for women's concussion injuries and were subsequently pooled. Costs from Accident Compensation Corporation (ACC) data were attributed to the results to provide cost estimates. RESULTS: The pooled analysis match injury incidence of women's concussion was higher for rugby league (10.3 per 1000 match hours) than rugby 15 s (2.8 per 1000 match hours) or rugby 7 s (8.9 per 1000 match hours). There was a fourfold difference in the pooled incidence of concussion in women's rugby league (risk ratio [RR] 4.53, 95% confidence interval [CI] 1.8-11.3]; p = 0.0001) when compared with rugby 15 s. There was also a ninefold higher risk of a concussion during match participation compared with training participation for women's rugby 15 s (RR 9.3, 95% CI 1.29-66.78; p = 0.0070). The total estimated costs for the concussions reported were NZ$1,235,101. For rugby 7 s, the pooled concussive injury burden was 33.2 days. CONCLUSIONS: Our pooled analysis clarified the extent of concussion injury and the possible associated costs at several levels of the game for women's rugby codes. The pooled mean days lost because of concussions was 33 days. As this was considerably longer than the 7- to 10-day expected timeframe outlined in the Concussion in Sport Consensus statement, these guidelines need to be updated to include sex-specific differences.

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

BACKGROUND: Management of concussion remains a serious issue for professional sports, particularly with the growing knowledge on the consequences of repetitive concussion. One primary concern is the subjective assessment of recovery that dictates the time until a concussed athlete is returned-to-competition. In response to this concern, the Australian Football League (AFL) changed its policy in 2020 such that medical clearance for return-to-competition was extended from 1 day, to a minimum of 5 days, prior to the next scheduled match. OBJECTIVE: We sought to explore the impact of the AFL policy change by asking whether time to return-to-competition after concussion was increased in the 2020 season relative to previous years. METHODS: Retrospective data on injury and return-to-competition were sourced from publicly available tables published by the AFL. Our primary exploration compared the number of matches missed and the number of days missed in concussed players across 2017-2020 inclusive, with secondary exploration analysing the proportion of players returning to play 12 days or longer. RESULTS: Analysis of data from 166 concussed players revealed no increase in the number of matches missed in 2020 relative to previous years as would have been expected from an extended recovery protocol. Comparing 2020 relative to 2017-2019, we found that there was an overall moderate reduction in median time to return-to-competition (RTC) in 2020 (10 vs 13 days, respectively d = - 0.345) and a significant reduction in players taking more than 12 days to RTC (p = 0.046). CONCLUSION: This exploratory study demonstrates that clubs may not have followed policy change around concussion management designed to increase time to RTC. Ongoing auditing is required to ensure player clearance meets policy goals, highlighting the need for objective measures for RTC after concussion.

A systematic review of the effects of educational interventions on knowledge and attitudes towards concussion for people involved in sport - Optimising concussion education based on current literature.

Educational interventions aimed at increasing concussion knowledge and attitudes are designed according to different frameworks. The aim of this systematic review of the literature was to determine the effects of educational interventions on concussion knowledge and attitudes, while providing recommendations for future research in the area of concussion education interventions. Data were extracted from 25 papers following a systematic search of the CINAHL, PubMed/Medline, Science Direct, SPORTDiscus and Web of Science scientific databases. Interventions were designed according to expert opinion and recommendations from previous research, such as knowledge transfer frameworks, the Health Belief Model, Theory of Planned Behaviour or by unknown means. Interventions were presented using PowerPoint presentations, videos, interactive computer modules, tool-kits, games and as guidelines. Interventions designed according to expert opinion increased concussion knowledge during post-intervention testing up to 2 weeks after intervention administration, and occasionally increased attitudes, with both knowledge and attitude improvements tending to return to baseline levels over-time. Interventions designed according to recommendations from previous research tend to increase both knowledge and attitudes with lack of follow-up data to determine long-term effects. Future concussion educational interventions should be designed according to expert opinion and using a knowledge transfer framework. The long-term effects of interventions require more research in order to design more effective educational tools.

Corticomotor correlates of somatosensory reaction time and variability in individuals with post concussion symptoms.

Persistent post concussion symptoms (PPCS) describe the condition when an individual experiences chronic symptoms, particularly fatigue, beyond the expected time of recovery. The aim of this study was to quantify the effect of fatigue and related ongoing symptoms on somatosensory and corticomotor pathways using reaction time (RT) testing, and single-pulse and paired-pulse transcranial magnetic stimulation (TMS). Eighty-three participants (nine female, mean age 37.9 ± 11.5 years) were divided into two groups (persistent symptoms versus asymptomatic) following self-report based upon previously published clinical symptom scores. All participants completed somatosensory and visuomotor RT testing, as well as corticomotor excitability and inhibition measurements via TMS. Participants in the persistent symptom group (n = 38) reported greater number of previous concussions (t = 2.81, p = 0.006) and significantly higher levels of fatigue and related symptoms in the asymptomatic group (n = 45; t = 11.32, p < 0.006). Somatosensory RT showed significant slowing and increased variability in the persistent symptoms group (p < 0.001), however no significant differences were observed between groups for visuomotor RTs. Transcranial magnetic stimulation revealed differences between groups for intracortical inhibition at all stimulus intensities and paired pulse measures. The results indicate that somatosensory and corticomotor systems reflect on-going fatigue. From a practical perspective, objective and simplistic measures such as somatosensory and corticomotor measures can be used in the assessment of PPCS and gauging the efficacy of post concussion rehabilitation programmes.

Physical Demands of Amateur Domestic and Representative Netball in One Season in New Zealand Assessed Using Heart Rate and Movement Analysis.

King, DA, Cummins, C, Hume, PA, and Clark, TN. Physical demands of amateur domestic and representative netball in one season in New Zealand assessed using heart rate and movement analysis. J Strength Cond Res 34(7): 2062-2070, 2020-The purpose of this descriptive cohort study was to describe physical demands of netball for positions and between playing levels using microtechnology. Data were collected from 34 female netball players across 3 teams at different levels (over 19 years representative [O19], under 19 years representative [U19], and open-age amateur club domestic) for 20 games using heart rate and microtechnology data. Total distance, maximal velocity, PlayerLoad ([PL] accumulated accelerometer-derived load), and individual PL vectors (PL forward [PLF], PL sideward [PLS] and PL vertical [PLV]) were examined. Analysis by playing level and netball position were conducted. The O19 players recorded a higher mean distance (3,365.7 ± 1,875.1 m) per match than U19 (p = 0.0095) players. The O19 players recorded a higher PL (p = 0.0003), PLF (p = 0.004), PLS (p = 0.0039), and PLV (p = 0.0352) than the domestic players. Domestic players recorded a higher maximal velocity than O19 players (p = 0.0003; d = 0.32) throughout the study. Domestic players recorded a higher average maximal heart rate (202.2 ± 28.2 b·min) than O19 (p < 0.0001) and U19 (p = 0.0002) players. Given the high physical demands of netball, individual player- and position-specific training programs are required to develop players for the specific demands of competition while also reducing the impact of excessive physical exertion to facilitate safer engagement within netball. The identification of the differing physical and physiological profiles of individual positional groups throughout match-play highlights the importance of integrating microtechnology into the routine monitoring of intermittent court-based sports, such as netball.

Neurophysiological abnormalities in individuals with persistent post-concussion symptoms.

Concussion injury results in a rapid onset of transient neurological impairment that can resolve quickly, or sometimes evolve over time, but usually resolve within seven to 10 days. However, a small but noticeable cohort (~10%) of individuals continues to experience persistent lingering effects, particularly fatigue, recognized as post-concussion symptoms (PCS). This study explored neurophysiological mechanisms in people with persistent PCS. Studies involved using self-report post-concussion fatigue scale, transcranial magnetic stimulation (TMS) and somatosensory stimulation in those with diagnosed PCS (n = 20; 36.1 ±â€¯14.0 yr., 4 female; mean time post-concussion 15.4 ±â€¯7.6 months) to fully recovered individuals (n = 20; 33.8 ±â€¯6.6 yr., 2 female; post-concussion 12.9 ±â€¯6.6 months) and healthy controls (n = 20; 37.7 ±â€¯8.0 yr., 3 female). PCS participants demonstrated a significantly higher self-report fatigue (score: PCS 20.2 [95% CI 17.4-22.9], Recovered 6.2 [3.1-9.3], Control 2.75 [0.6-4.8]). PCS participants showed a worsening of reaction time (F2,57 = 4.214; p = 0.020) and increased reaction time variability (F2,57 = 5.505; p = 0.007). Somatosensory differences were observed for amplitude discrimination (F2,57 = 5.166; p = 0.009), temporal order judgment (F2,57 = 4.606; p = 0.014) and duration discrimination (F2,57 = 6.081; p = 0.004). Increased intracortical inhibition in TMS single pulse suprathreshold stimulation (110%: F2,57 = 6.842; p = 0.002; 130%: F2,57 = 4.900; p = 0.011; 150%: F2,57 = 4.638; p = 0.014; 170%: F2,57 = 9.845; p < 0.001) and paired pulse protocols was also seen (SICI: F2,57 = 23.390; p < 0.001, and LICI: F2,57 = 21.603; p < 0.001). Using non-invasive stimulation techniques, this novel study showed increased cortical inhibition and compromised central information processing, suggesting neural mechanisms underpinning ongoing fatigue, allowing for potential clinical rehabilitation strategies.

Head impact exposure from match participation in women's rugby league over one season of domestic competition.

OBJECTIVES: To quantify the magnitude, frequency, duration and distribution of head impact exposure in a women's rugby league competition. DESIGN: Prospective cohort study. METHODS: Twenty-one players had a wireless impact measuring device (X2Biosystems XPatch) behind their right ear during match participation. Head impact data were collected and downloaded for analysis. Median peak linear and rotational accelerations and impact locations between player positions were assessed using a Friedman repeated measures ANOVA on ranks with a Wilcoxon signed-rank test for post hoc analysis with a Bonferroni correction. RESULTS: A total of 1659 impacts to the head >10g were recorded (range 10g-91g) over the nine competition matches. There was a mean of 184±18 impacts per-match resulting in a mean of 14±12 impacts per-player per-match. The No. 8 prop recorded a mean of 29±27 impacts per-match, the No. 12 second-row forward recorded the highest median peak resultant linear acceleration (16g) per-match and the No. 11 second-row forward recorded the highest median peak resultant rotational acceleration (3696rad/s2). CONCLUSIONS: Our cohort of 21 female rugby league athletes were exposed to repetitive sub-concussive head impact exposure with an average of 14 impacts per-player per-match. Forwards were exposed to more impacts per-match than backs and these impacts were of higher magnitude. Most impacts occurred on the side of the head and were sustained during the second half of the game. Clinicians, coaches and players should be aware of the rates and magnitude of head impacts in female rugby league athletes.

Similar head impact acceleration measured using instrumented ear patches in a junior rugby union team during matches in comparison with other sports.

OBJECTIVE Direct impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion. METHODS This descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches. RESULTS A total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37-58), resulting in 10 (IQR 4-18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g-21g) for linear acceleration and 2296 rad/sec(2) (IQR 1352-4152 rad/sec(2)) for rotational acceleration. CONCLUSIONS There were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players.

Neck back and spine injuries in amateur rugby league: a review of nine years of Accident Compensation Corporation injury entitlement claims and costs.

Rugby league is a popular participation sport, but there have been concerns raised regarding the possible high number of severe neck, back and spine injuries. Therefore an epidemiological overview of rugby league neck, back and spine injuries and associated costs of these injuries was undertaken in one country over nine years. The New Zealand national Accident Compensation Corporation data for moderate to serious injury entitlement claims (MSC) over nine years were analysed for the number, type and cost of neck, back and spine rugby league injuries resulting in medical treatment. There were 206 (3%) neck, back and spine MSC claims totalling NZD$1,585,927 (4%) of the total injury entitlement costs for rugby league over the nine-year period. The rate of MSC neck, back and spine rugby league injuries was 26 per 1000 total rugby league claims. Although the rate of neck, back and spine injuries varied over the nine years from 22 to 40 per 1000 injury claims, there was a significant increase over the duration of the study in the number of neck, back and spine MSC claims (χ2=849, df=8, p<0.001), and the cost per MSC injury claim (χ2=19,054, df=8, p<0.001). The frequency, severity and first 12 months cost of neck, back and spine injuries in rugby league is an issue that needs to be addressed. Unfortunately the ACC data base does not provide information on how or why the injuries occurred. A prospective injury epidemiology study needs to be conducted that will allow collection of information surrounding the mechanisms of injury and possible causative risk factors such as tackling technique. In the meantime it is suggested that coaches should ensure tackling technique is correctly taught to all rugby league players to reduce the risk of neck, back and spine injury. Team medical personnel should be trained in dealing with neck and spine injuries as well as head related injuries, and emergency procedures in dealing with players with a suspected neck or back injury should be practiced at clubs.

Match and training injuries in rugby league: a review of published studies.

Rugby league is an international collision sport played by junior, amateur, semiprofessional and professional players. The game requires participants to be involved in physically demanding activities such as running, tackling, passing and sprinting, and musculoskeletal injuries are common. A review of injuries in junior and senior rugby league players published in Sports Medicine in 2004 reported that injuries to the head and neck and muscular injuries were common in senior rugby league players, while fractures and injuries to the knee were common in junior players. This current review updates the descriptive data on rugby league epidemiology and adds information for semiprofessional, amateur and junior levels of participation in both match and training environments using studies identified through searches of PubMed, CINHAL, Ovid, MEDLINE, SCOPUS and SportDiscus databases. This review also discusses the issues surrounding the definitions of injury exposure, injury rate, injury severity and classification of injury site and type for rugby league injuries. Studies on the incidence of injuries in rugby league have suffered from inconsistencies in the injury definitions utilized. Some studies on rugby league injuries have utilized a criterion of a missed matchas an injury definition, total injury incidences or a combination of both time-loss and non-time-loss injuries, while other studies have incorporated a medical treatment injury definition. Efforts to establish a standard definition for rugby league injuries have been difficult, especially as some researchers were not in favour of a definition that was all-encompassing and enabled non-time-loss injuries to be recorded. A definition of rugby league injury has been suggested based on agreement by a group of international researchers. The majority of injuries occur in the match environment, with rates typically increasing as the playing level increases. However, professional level injury rates were reportedly less than semiprofessional participation. Only a few studies have reported training injuries in rugby league, where injury rates were reported to be less than match injuries. Approximately 16-30% of all rugby league injuries have been reported as severe, which places demands upon other team members and, if the player returns to playing too early, places them at an increased risk of further injuries. Early research in rugby league identified that ligament and joint injuries were the common injuries, occurring primarily to the knee. More recently, studies have shown a change in anatomical injury sites at all levels of participation. Although the lower limb was the frequent injury region reported previously, the shoulder has now been reported to be the most common injury site. Changes in injury site and type could be used to prompt further research and development of injury reduction programmes to readdress the issue of injuries that occur as a result of participation in rugby league activities. Further research is warranted at all participation levels of rugby league in both the match and training environments to confirm the strongest risk factors for injury.

Injuries in amateur rugby league matches in New Zealand: a comparison between a division 1 and a division 2 premier grade team.

OBJECTIVE: To investigate the incidence, site, nature, and severity of injuries in amateur rugby league in New Zealand at 2 different participation levels. DESIGN: A nonconcurrent observational prospective cohort study design. SETTING: Rugby league match environment over the 2006 (division 2) and 2008 (division 1) competition seasons. PARTICIPANTS: Members of the rugby league team participating in match activities. ASSESSMENT OF RISK FACTORS: For each injury, it was recorded in which division it occurred; how many games, if any, were subsequently missed; and the type, site, and severity of injury. MAIN OUTCOME MEASURES: Injuries were reported as rate per 1000 hours, also broken down into severity according to the number of games missed. RESULTS: Over the duration of the study periods, there was a combined total of 372 (division 1: 166 and division 2: 206) injuries recorded. The combined injury rate was 405 per 1000 playing hours (division 1: 266 per 1000 playing hours and division 2: 700 per 1000 playing hours). CONCLUSIONS: The total injury incidence was higher than those previously reported for amateur and professional rugby league competitions. The incidence of missed match injuries for this study is also higher than missed match injuries reported for amateur, semiprofessional, and professional level competitions. The results of this study suggest that division 2 participants may have a lower fitness and skill level than division 1 participants. Further multidistrict prospective studies on the incidence of injuries in amateur rugby league competitions in New Zealand would enable further clarification on the actual total and missed match injury incidence and the incidence of tackle-related injuries in amateur competitions throughout New Zealand.

For debate: consensus injury definitions in team sports should focus on encompassing all injuries.

OBJECTIVE: The purpose of this paper is to highlight the most effective method of collecting injury data by using a definition that encompasses all injuries into the data collection system. The definition provides an accurate picture of injury incidence and also allows filtering of records so that data can be reported in a variety of comparable ways. DATA SOURCES/SYNTHESIS: A qualitative review of literature in team sports, plus expert opinion, served as the basis for data collection strategies. Articles were retrieved from SportsDiscus and PubMed using the terms "sports injury definition" and "injury definition." These terms were searched for the period 1966 to November 2006. RESULTS: One of the major results (from this paper) that supports the use of an all-encompassing injury definition is that 70% to 92% of all injuries sustained fall into the transient category--that is, by only recording injuries that result in missed matches, the majority of injuries are missed and therefore injury rates are underreported. CONCLUSION: An injury definition should be the most encompassing definition that enables a true, global picture of injury incidence to be seen in participation in any team sport.