Risk factors for head injury events in professional rugby union: a video analysis of 464 head injury events to inform proposed injury prevention strategies.

OBJECTIVES: The tackle is responsible for the majority of head injuries during rugby union. In order to address head injury risk, risk factors during the tackle must first be identified. This study analysed tackle characteristics in the professional game in order to inform potential interventions. METHODS: 464 tackles resulting in a head injury assessment (HIA) were analysed in detail, with tackle type, direction, speed, acceleration, nature of head contact and player body position the characteristics of interest. RESULTS: Propensity to cause an HIA was significantly greater for active shoulder tackles, front-on tackles, high speeder tackles and an accelerating tackler. Head contact between a tackler's head and ball carrier's head or shoulder was significantly more likely to cause an HIA than contact below the level of the shoulder (incident rate ratio (IRR) 4.25, 95%-CI 3.38 to 5.35). The tackler experiences the majority (78%) of HIAs when head-to-head contact occurs. An upright tackler was 1.5 times more likely to experience an HIA than a bent at the waist tackler (IRR 1.44, 95% CI 1.18 to 1.76). CONCLUSIONS: This study confirms that energy transfer in the tackle is a risk factor for head injury, since direction, type and speed all influence HIA propensity. The study provides evidence that body position and the height of tackles should be a focus for interventions, since lowering height and adopting a bent at the waist body position is associated with reduced risk for both tacklers and ball carriers. To this end, World Rugby has implemented law change based on the present data.

Kumanu Tangata: the aftermatch study - protocol to examine the health outcomes of high-level male rugby union players using linked administrative data.

There is increasing interest in the potential long-term outcomes of participation in contact and collision sports, driven by evidence of higher rates of neurodegenerative diseases among former athletes. Recent research has capitalised on large-scale administrative health data to examine health outcomes in contact sport athletes. However, there is limited research on outcomes associated with participation in rugby union, a contact sport with a relatively high incidence of head trauma and musculoskeletal injuries. Additionally, there is scope to investigate a greater range of health outcomes using large, population-based administrative data. The Kumanu Tangata project is a retrospective cohort study that will use linked information from the New Zealand Rugby Register and health records within a comprehensive deidentified whole-population administrative research database known as the Integrated Data Infrastructure. First-class male rugby union players (N=13 227) will be compared with a general population comparison group (N=2 438 484; weighting will be applied due to demographic differences) on a range of mortality and morbidity outcomes (neurodegenerative diseases, musculoskeletal conditions, chronic physical conditions, mental health outcomes). A range of player-specific variables will also be investigated as risk factors. Analyses will consist primarily of Cox proportional hazards models. Ethics approval for the study has been granted by the Auckland Health Research Ethics Committee (Ref. AH23203). Primary research dissemination will be via peer-reviewed journal articles.

Injury in Starting and Replacement Players from Five Professional Men's Rugby Unions.

OBJECTIVES: The aim of this study was to compare the incidence, severity, and burden of injury in starting and replacement players from professional men's teams of five rugby unions. METHODS: Match injuries of greater than 24 h time-loss (including data on the severity, match quarter, event, body region) and player minutes of match exposure data were collated for all starting and replacement players in the men's English Premiership, Welsh Pro14 (both 2016/17-2018/19 seasons), and Australian, New Zealand, and South African Super Rugby (all 2016-2018 seasons) teams. Injury incidences and mean injury burden (incidence × days missed) were calculated, and rate ratios (RRs) (95% confidence intervals [CIs]) were used to compare injury incidence and burden between starting (reference group) and replacement players. RESULTS: Overall injury incidence was not different between starters and replacements for all injuries (RR = 0.98, 95% CI 0.88-1.10), nor for concussions (RR = 0.85; 95% CI 0.66-1.11). Mean injury burden was higher for replacement players (RR = 1.31, 95% CI 1.17-1.46). Replacement injury incidence was lower than the starters in the third (RR = 0.68, 95% CI 0.51-0.92) and fourth (RR = 0.78, 95% CI 0.67-0.92) match quarters. Injury incidence was not different between starters and replacements for any match event or body region, but compared with starters, replacements' injury burden was higher in lower limbs (RR = 1.24, 95% CI 1.05-1.46) and in the tackled player (RR = 1.30, 95% CI 1.01-1.66). CONCLUSION: This study demonstrated a lower injury incidence in replacement players compared with starters in the second half of matches, with a higher injury burden for replacement players due to higher mean injury severity.

COVID-19 Lockdown: A Global Study Investigating the Effect of Athletes' Sport Classification and Sex on Training Practices.

PURPOSE: To investigate differences in athletes' knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. METHODS: Athletes (12,526; 66% male; 142 countries) completed an online survey (May-July 2020) assessing knowledge, beliefs, and practices toward training. Sports were classified as team sports (45%), endurance (20%), power/technical (10%), combat (9%), aquatic (6%), recreational (4%), racquet (3%), precision (2%), parasports (1%), and others (1%). Further analysis by sex was performed. RESULTS: During lockdown, athletes practiced body-weight-based exercises routinely (67% females and 64% males), ranging from 50% (precision) to 78% (parasports). More sport-specific technical skills were performed in combat, parasports, and precision (∼50%) than other sports (∼35%). Most athletes (range: 50% [parasports] to 75% [endurance]) performed cardiorespiratory training (trivial sex differences). Compared to prelockdown, perceived training intensity was reduced by 29% to 41%, depending on sport (largest decline: ∼38% in team sports, unaffected by sex). Some athletes (range: 7%-49%) maintained their training intensity for strength, endurance, speed, plyometric, change-of-direction, and technical training. Athletes who previously trained ≥5 sessions per week reduced their volume (range: 18%-28%) during lockdown. The proportion of athletes (81%) training ≥60 min/session reduced by 31% to 43% during lockdown. Males and females had comparable moderate levels of training knowledge (56% vs 58%) and beliefs/attitudes (54% vs 56%). CONCLUSIONS: Changes in athletes' training practices were sport-specific, with few or no sex differences. Team-based sports were generally more susceptible to changes than individual sports. Policy makers should provide athletes with specific training arrangements and educational resources to facilitate remote and/or home-based training during lockdown-type events.

Injury Risk in New Zealand Rugby Union: A Nationwide Study of Injury Insurance Claims from 2005 to 2017.

OBJECTIVES: The Accident Compensation Corporation is a compulsory, 24-h, no-fault personal injury insurance scheme in New Zealand. The purpose of this large-scale retrospective cohort study was to use Accident Compensation Corporation records to provide information about rugby injury epidemiology in New Zealand, with a focus on describing differences in risk by age and gender. METHODS: A total of 635,657 rugby injury claims were made to the Accident Compensation Corporation for players aged 5-40 years over the period 2005-2017. Information about player numbers and estimates of player exposure was obtained from New Zealand Rugby, the administrative organisation for rugby in New Zealand. RESULTS: Over three quarters of claims (76%) were for soft-tissue injuries, with 11% resulting from fractures or dislocations, 6.7% from lacerations, 3.1% from concussions and 2.0% from dental injuries. Body regions injured included shoulder (14%), knee (14%), wrist/hand (13%), neck/spine (13%), head/face (12%), leg (11%) and ankle (10%). The probability of a player making at least one injury claim in a season (expressed as a percentage) was calculated under the assumption that the incidence of claims follows a Poisson distribution. Players aged 5-6 years had a probability of making at least one claim per season of 1.0%, compared to 8.3% for players aged 7-12 years, 35% for age 13-17 years, 53% for age 18-20 years, 57% for age 21-30 years and 47% for age 31-40 years. The overall probability of making at least one claim per season across all age groups was 29%. The relative claim rate for adults (players aged 18 years and over) was 3.92 (90% confidence interval 3.90-3.94) times that of children. Ten percent of players were female, and they sustained 6% of the injuries. Overall, the relative claim rate for female players was 0.57 times that of male players (90% confidence interval 0.56-0.58). The relative claim rate of female to male players tended to increase with age. There were very few female players aged over 30 years; however, those who did play had higher claim rates than male players of the same age group (1.49; 90% confidence interval 1.45-1.53). CONCLUSIONS: Injuries resulting from rugby are distributed across the body, and most of the claims are for soft-tissue injuries. Rates of injury increase rapidly through the teenage years until the early 20 s; for male players they then decrease until the mid-30 s. For female players, the injury rate does not decrease as players move into their 30 s. Combining Accident Compensation Corporation injury claim data with national player registration data provides useful information about the risks faced by New Zealand's community rugby players, and the insights derived are used in the development of rugby injury prevention programme content.

Correction to: Injury Risk in New Zealand Rugby Union: A Nationwide Study of Injury Insurance Claims from 2005 to 2017.

Page 11, column 2, section 4.2 Injury Epidemiology, paragraph 4.

Evaluation of RugbySmart: a rugby union community injury prevention programme.

RugbySmart, a rugby union injury prevention programme, was launched in New Zealand in 2001. It was compulsory for all coaches and referees to complete RugbySmart requirements annually in order to continue coaching or refereeing. After 5 years of implementation the programme partners, Accident Compensation Corporation and New Zealand Rugby Union, evaluated RugbySmart to determine its effectiveness in reducing injuries. The purpose was to evaluate the effect of RugbySmart on reducing injury rates per 100,000 players and resulting injury prevention behaviours. The RugbySmart programme was associated with a decrease in injury claims per 100,000 players in most areas the programme targeted; the programme had negligible impact on non-targeted injury sites. The decrease in injury claims numbers was supported by results from the player behaviour surveys pre- and post-RugbySmart. There was an increase in safe behaviour in the contact situations of tackle, scrum and ruck technique.

Guidelines for community-based injury surveillance in rugby union.

OBJECTIVES: The vast majority of rugby union ('rugby') participants are community-based players; however, the majority of injury surveillance studies reported relate to the elite, professional game. A potential reason for this dearth of studies could be the perceived difficulty of using the consensus statement for injury recording at the community level. The aim of this study was to identify areas where the consensus statement could be adapted for easier and more appropriate implementation within the community setting. DESIGN: Round-table discussion. METHODS: All community-based injury surveillance issues were discussed during a 2-day facilitated round-table meeting, by an 11-person working group consisting of researchers currently active in rugby-related injury surveillance, sports medicine and sports science issues. The outcomes from the meeting were summarised in a draft guidance document that was then subjected to an extensive iterative review prior to producing methodological recommendations. RESULTS: Each aspect of the rugby-specific consensus statement was reviewed to determine whether it was feasible to implement the standards required in the context of non-elite rugby and the resources available within in a community setting. Final recommendations are presented within a community-based injury report form. CONCLUSIONS: It is recommended that whenever possible the rugby-specific consensus statement for injury surveillance studies be used: this paper presents an adapted report form that can be used to record injury surveillance information in community rugby if suitable medical support is not available.

Tackle technique of rugby union players during head impact tackles compared to injury free tackles.

OBJECTIVES: The majority of head injuries in rugby union occur during tackles in which the head receives an impact. Head impacted tackles may be a result of poor tackle technique. Therefore, the purpose of this study was to analyse ball-carrier and tackler technique proficiency in head impacted tackles and compare the technique proficiency to successfully completed tackles in real-match situations. DESIGN: Retrospective video analysis. METHODS: Video footage of head impacts with the 'head impacted player' (n=157) and the opposing player 'impacting player' (n=156) were scored for contact technique using a list of technical criteria and compared to contact technique scores of role and tackle-type matched injury-free, successful tackles (n=170). RESULTS: Ball-carriers contacting their head during front-on head impacted tackles (mean 6.4, 95%CI 5.6-7.1 AU, out of a total score of 14) scored significantly less than the 'impacting player' (mean 8.1, 95%CI 7.1-9.1 AU, p<0.01, ES=0.5, small) and successful ball-carriers (successful ball-carrier mean 9.4, 95%CI 8.9-9.9 AU, p<0.0001, ES=1.1, moderate). Tackler contact proficiency scores during successful front-on tackles (mean 12.3, 95%CI 11.6-12.9 AU, out of a total score of 16) were significantly greater than tackler contact proficiency scores for the 'head impacted player' (mean 9.8, 95%CI 8.6-10.9, p<0.001, ES=0.8, moderate) and 'impacting player' (mean 9.3, 95%CI 8.4-10.1, p<0.0001, ES=1.0, moderate). CONCLUSIONS: Both the ball-carrier and tackler have a technical deficiency when there is a head impact in matches. The implication of this finding is that players and coaches need to acknowledge that both the ball-carrier and tackler are responsible for each other's safety during the tackle.