Description:
The grading of Australian junior and youth rugby union players has received substantial media attention in recent years. Media reports have focussed on size mismatches observed between players, especially players with Polynesian heritage, and the concerned parents who fear for the safety of their child owing to perceived mismatches. Although such concerns are well meaning, few media reports recognise the need for substantial evidence to determine the best grading system for junior and youth rugby union players. The current study reviewed relevant literature pertinent to the grading and dispensation of junior and youth rugby union players. Using primary and secondary search strategies, a total of 33 articles reporting the anthropometric characteristics of junior and youth rugby players were identified. Anthropometric data from the literature were compared with normative population data and currently used dispensation criteria. Junior and youth rugby players were found to be taller and heavier than normative population data. Current dispensation criteria, in terms of body mass, were found to vary and it is suggested that criteria be revised and standardised across rugby unions throughout Australia. Although it is acknowledged that other factors are important for grading players, anthropometric characteristics should be considered as potential dispensation criteria to supplement current age-based grading for junior and youth rugby union players. Measuring the body mass and stature of each junior player upon pre-season registration is suggested, which would provide data to establish valid dispensation criteria for the following season.
Description:
Background Concussion is common in the sporting arena and is often challenging to diagnose. The development of wearable head impact measurement systems has enabled measurement of head kinematics in contact sports. Objectives The objective of this systematic review was to determine the characteristics of head kinematics measured by an accelerometer system among male athletes diagnosed with concussion. Methods A systematic search was conducted in July 2015. Inclusion criteria were English-language studies published after 1990 with a study population of male athletes, in any sport, where objectively measured biomechanical forces were reported in the setting of a concussive event. The random effects meta-analysis model was used to combine estimates of biomechanical force measurements in concussed athletes. Results Thirteen studies met the inclusion criteria, the majority of which were conducted with high school and college football teams in the US. Included studies measured a combination of linear and rotational acceleration. The meta-analysed mean peak linear head acceleration associated with a concussive episode was 98.68 g (95 % CI 82.36-115.00) and mean peak rotational head acceleration was 5776.60 rads/s 2 (95 % CI 4583.53-6969.67). The estimates of the biomechanical forces were consistent across studies, with I 2 values of 0 % for both metaanalyses. Conclusions Head impact monitoring through accelerometery has been shown to be useful with regard to characterising the kinematic load to the head associated with concussion. Future research with improved clinical outcome measures and head kinematic data may improve accuracy when evaluating concussion, and may assist with both interpretation of biomechanical data and the development and utilisation of implementation strategies for the technology.
Description:
Objectives: To assess the utility and functionality of the X-Patch® as a measurement tool to study head impact exposure in Australian Football. Accuracy, precision, reliability and validity were examined. Designs: Laboratory tests and prospective observational study. Methods: Laboratory tests on X-Patch® were undertaken using an instrumented Hybrid III head and neck and linear impactor. Differences between X-Patch® and reference data were analysed. Australian Football players wore the X-Patch® devices and games were video-recorded. Video recordings were analysed qualitatively for head impact events and these were correlated with X-Patch® head acceleration events. Wearability of the X-Patch® was assessed using the Comfort Rating Scale for Wearable Computers. Results: Laboratory head impacts, performed at multiple impact sites and velocities, identified significant correlations between headform-measured and device-measured kinematic parameters (p < 0.05 for all). On average, the X-Patch®-recorded peak linear acceleration (PLA) was 17% greater than the reference PLA, 28% less for peak rotational acceleration (PRA) and 101% greater for the Head Injury Criterion (HIC). For video analysis, 118 head acceleration events (HAE) were included with PLA ≥30 g across 53 players. Video recordings of X-Patch®-measured HAEs (PLA ≥30 g) determined that 31.4% were direct head impacts, 9.3% were indirect impacts, 44.1% were unknown or unclear and 15.3% were neither direct nor indirect head impacts. The X-Patch® system was deemed wearable by 95–100% of respondents. Conclusions: This study reinforces evidence that use of the current X-Patch® devices should be limited to research only and in conjunction with video analysis.
Description:
Traumatic brain injury (TBI) is the leading cause of death in alpine skiing. It has been found that helmet use can reduce the incidence of head injuries between 15% and 60%. However, knowledge on optimal helmet performance criteria in World Cup alpine skiing is currently limited owing to the lack of biomechanical data from real crash situations. Purpose: This study aimed to estimate impact velocities in a severe TBI case in World Cup alpine skiing. Methods: Video sequences from a TBI case in World Cup alpine skiing were analyzed using a model-based image matching technique. Video sequences from four camera views were obtained in full high-definition (1080p) format. A three-dimensional model of the course was built based on accurate measurements of piste landmarks and matched to the background video footage using the animation software Poser 4. A trunk-neck-head model was used for tracking the skier's trajectory. Results: Immediately before head impact, the downward velocity component was estimated to be 8 m.s(-1). After impact, the upward velocity was 3 m.s(-1), whereas the velocity parallel to the slope surface was reduced from 33 m.s(-1) to 22 m.s(-1). The frontal plane angular velocity of the head changed from 80 radIsj1 left tilt immediately before impact to 20 rad.s(-1) right tilt immediately after impact. Conclusions: A unique combination of high-definition video footage and accurate measurements of landmarks in the slope made possible a high-quality analysis of head impact velocity in a severe TBI case. The estimates can provide crucial information on how to prevent TBI through helmet performance criteria and design.
Description:
Traumatic brain injury (TBI) is the leading cause of death in alpine skiing. It has been found that helmet use can reduce the incidence of head injuries between 15% and 60%. However, knowledge on optimal helmet performance criteria in World Cup alpine skiing is currently limited owing to the lack of biomechanical data from real crash situations. Purpose: This study aimed to estimate impact velocities in a severe TBI case in World Cup alpine skiing. Methods: Video sequences from a TBI case in World Cup alpine skiing were analyzed using a model-based image matching technique. Video sequences from four camera views were obtained in full high-definition (1080p) format. A three-dimensional model of the course was built based on accurate measurements of piste landmarks and matched to the background video footage using the animation software Poser 4. A trunk-neck-head model was used for tracking the skier's trajectory. Results: Immediately before head impact, the downward velocity component was estimated to be 8 m.s(-1). After impact, the upward velocity was 3 m.s(-1), whereas the velocity parallel to the slope surface was reduced from 33 m.s(-1) to 22 m.s(-1). The frontal plane angular velocity of the head changed from 80 radIsj1 left tilt immediately before impact to 20 rad.s(-1) right tilt immediately after impact. Conclusions: A unique combination of high-definition video footage and accurate measurements of landmarks in the slope made possible a high-quality analysis of head impact velocity in a severe TBI case. The estimates can provide crucial information on how to prevent TBI through helmet performance criteria and design.
Description:
Over the past century, technology has made it possible to measure human motion in many ways and with new levels of precision, becoming a tool in many applications and professional branches including medicine, sports science and forensics. Some branches have developed in response to the technology, such as the emergence of motion-capture animation in the film industry. These different applications use the same or similar types of equipment with the general intention of making the systems as intuitive as possible for the participants. However, the methodologies necessary to produce reliable results in these areas differ enormously. The overlap of information between fields might lead to situations where small but important adaptations are required in order to produce the required result; experts with knowledge of one field might not be aware of such developments. The Handbook of Human Motion brings together contributions from many different disciplines, covering the established and emerging technologies employed, the challenges posed in each area of application and the novel solutions reached by researchers.
Description:
Abstract: A retrospective case-series study of pedal- and motorcyclists presenting to a major metropolitan trauma centre over an 18 month period was undertaken. The injury data were coded according to a number of outcome variables, including intracranial injury of AIS severity >/= 2. Helmet use was coded. After stratification by rider type, data were analysed to examine the relationships between helmet use and injury using logistic regression. A total of 220 injured motorcycle riders and 137 injured pedal cyclists met the study's inclusion criteria, with 195 motorcycle riders and passengers (88.6%) and 87 pedal cyclists (63.5%) wearing helmets. Helmets were associated with a significant reduction (p<0.05) in the likelihood of head and intracranial injury in both rider groups. Associated with helmet use was a reduction in intracranial injury likelihood of 66% for both helmeted motorcycle riders and pedal cyclists. The study is further evidence of the benefits offered by helmets.
Description:
Abstract: A retrospective case-series study of pedal- and motorcyclists presenting to a major metropolitan trauma centre over an 18 month period was undertaken. The injury data were coded according to a number of outcome variables, including intracranial injury of AIS severity >/= 2. Helmet use was coded. After stratification by rider type, data were analysed to examine the relationships between helmet use and injury using logistic regression. A total of 220 injured motorcycle riders and 137 injured pedal cyclists met the study's inclusion criteria, with 195 motorcycle riders and passengers (88.6%) and 87 pedal cyclists (63.5%) wearing helmets. Helmets were associated with a significant reduction (p<0.05) in the likelihood of head and intracranial injury in both rider groups. Associated with helmet use was a reduction in intracranial injury likelihood of 66% for both helmeted motorcycle riders and pedal cyclists. The study is further evidence of the benefits offered by helmets.
Description:
Objectives: One of the main requirements of a protective bicycle helmet is to provide and maintain adequate coverage to the head. A poorly fitting or fastened helmet may be displaced during normal use or even ejected during a crash. The aims of the current study were to identify factors that influence the size of helmet worn, identify factors that influence helmet position and adjustment, and examine the effects of helmet size worn and adjustment on helmet stability. Methods: Recreational and commuter cyclists in Sydney were surveyed to determine how helmet size and/or adjustment affected helmet stability in the real world. Anthropometric characteristics of the head were measured and, to assess helmet stability, a test analogous to the requirements of the Australian bicycle helmet standard was undertaken. Results: Two hundred sixty-seven cyclists were recruited across all age groups and 91% wore an AS/NZS 2063-compliant helmet. The main ethnic group was Europeans (71%) followed by Asians (18%). The circumferences of the cyclists' heads matched well the circumference of the relevant ISO headform for the chosen helmet size, but the head shapes differed with respect to ISO headforms. Age and gender were associated with wearing an incorrectly sized helmet and helmet adjustment. Older males (>55 years) were most likely to wear an incorrectly sized helmet. Adult males in the 35-54 year age group were most likely to wear a correctly adjusted helmet. Using quasistatic helmet stability tests, it was found that the correctness of adjustment, rather than size, head dimensions, or shape, significantly affected helmet stability in all test directions. Conclusions: Bicycle helmets worn by recreational and commuter cyclists are often the wrong size and are often worn and adjusted incorrectly, especially in children and young people. Cyclists need to be encouraged to adjust their helmets correctly. Current headforms used in standards testing may not be representative of cyclists' head shapes. This may create challenges to helmet suppliers if on one hand they optimize the helmet to meet tests on ISO-related headforms while on the other seeking to offer greater range of sizes.
Description:
There has been an increasing focus on the role of helmets in reducing the risk of concussion in sport. Helmets in some sports have a well-established effect on reducing the risk of moderate to severe head injury, but the additional potential for helmets that have satisfi ed that objective to prevent concussion is unclear. Furthermore, the risk of moderate to severe head injury in some sports is low, e.g., rugby union and Australian rules football; however, there is clear risk of concussion in these sports, which presents an opportunity for helmets to mitigate that risk only. This chapter addresses the biomechanical studies of impact and helmet protection in sport.
Description:
Background: The paper presents a novel laboratory method for assessing boxing headguard impact performance. The method is applied to examine the effects of headguards on head impact dynamics and injury risk. Methods: A linear impactor was developed, and a range of impacts was delivered to an instrumented Hybrid III head and neck system both with and without an AIBA (Association Internationale de Boxe Amateur)- approved headguard. Impacts at selected speeds between 4.1 and 8.3 m/s were undertaken. The impactor mass was approximately 4 kg and an interface comprising a semirigid 'fist' with a glove was used. Results: The peak contact forces were in the range 1.9-5.9 kN. Differences in head impact responses between the Top Ten AIBA-approved headguard and bare headform in the lateral and forehead tests were large and/or significant. In the 8.3 m/s fist-glove impacts, the mean peak resultant headform accelerations for bare headform tests was approximately 130 g compared with approximately 85 g in the forehead impacts. In the 6.85 m/s bare headform impacts, mean peak resultant angular head accelerations were in the range of 5200-5600 rad/s
Description:
Background: Electronic methods are increasingly being used to manage health-related data among sporting populations. Collection of such data permits the analysis of injury and illness trends, improves early detection of injuries and illnesses, collectively referred to as health problems, and provides evidence to inform prevention strategies. The Athlete Management System (AMS) has been employed across a range of sports to monitor health. Australian combat athletes train across the country without dedicated national medical or sports science teams to monitor and advocate for their health. Employing a Web-based system, such as the AMS, May provide an avenue to increase the visibility of health problems experienced by combat athletes and deliver key information to stakeholders detailing where prevention programs May be targeted. Objective: The objectives of this paper are to (1) report on the feasibility of utilizing the AMS to collect longitudinal injury and illness data of combat sports athletes and (2) describe the type, location, severity, and recurrence of injuries and illnesses that the cohort of athletes experience across a 12-week period. Methods: We invited 26 elite and developing athletes from 4 Olympic combat sports (boxing, judo, taekwondo, and wrestling) to participate in this study. Engagement with the AMS was measured, and collected health problems (injuries or illnesses) were coded using the Orchard Sports Injury Classification System (version 10.1) and International Classification of Primary Care (version 2). Results: Despite >160 contacts, athlete engagement with online tools was poor, with only 13% compliance across the 12-week period. No taekwondo or wrestling athletes were compliant. Despite low overall engagement, a large number of injuries or illness were recorded across 11 athletes who entered data—22 unique injuries, 8 unique illnesses, 30 recurrent injuries, and 2 recurrent illnesses. The most frequent injuries were to the knee in boxing (n=41) and thigh in judo (n=9). In this cohort, judo players experienced more severe, but less frequent, injuries than boxers, yet judo players sustained more illnesses than boxers. In 97.0% (126/130) of cases, athletes in this cohort continued to train irrespective of their health problems. Conclusions: Among athletes who reported injuries, many reported multiple conditions, indicating a need for health monitoring in Australian combat sports. A number of factors May have influenced engagement with the AMS, including access to the internet, the design of the system, coach views on the system, previous experiences with the system, and the existing culture within Australian combat sports. To increase engagement, there May be a requirement for sports staff to provide relevant feedback on data entered into the system. Until the Barriers are addressed, it is not feasible to implement the system in its current form across a larger cohort of combat athletes.
Description:
Background: Electronic methods are increasingly being used to manage health-related data among sporting populations. Collection of such data permits the analysis of injury and illness trends, improves early detection of injuries and illnesses, collectively referred to as health problems, and provides evidence to inform prevention strategies. The Athlete Management System (AMS) has been employed across a range of sports to monitor health. Australian combat athletes train across the country without dedicated national medical or sports science teams to monitor and advocate for their health. Employing a Web-based system, such as the AMS, May provide an avenue to increase the visibility of health problems experienced by combat athletes and deliver key information to stakeholders detailing where prevention programs May be targeted. Objective: The objectives of this paper are to (1) report on the feasibility of utilizing the AMS to collect longitudinal injury and illness data of combat sports athletes and (2) describe the type, location, severity, and recurrence of injuries and illnesses that the cohort of athletes experience across a 12-week period. Methods: We invited 26 elite and developing athletes from 4 Olympic combat sports (boxing, judo, taekwondo, and wrestling) to participate in this study. Engagement with the AMS was measured, and collected health problems (injuries or illnesses) were coded using the Orchard Sports Injury Classification System (version 10.1) and International Classification of Primary Care (version 2). Results: Despite >160 contacts, athlete engagement with online tools was poor, with only 13% compliance across the 12-week period. No taekwondo or wrestling athletes were compliant. Despite low overall engagement, a large number of injuries or illness were recorded across 11 athletes who entered data—22 unique injuries, 8 unique illnesses, 30 recurrent injuries, and 2 recurrent illnesses. The most frequent injuries were to the knee in boxing (n=41) and thigh in judo (n=9). In this cohort, judo players experienced more severe, but less frequent, injuries than boxers, yet judo players sustained more illnesses than boxers. In 97.0% (126/130) of cases, athletes in this cohort continued to train irrespective of their health problems. Conclusions: Among athletes who reported injuries, many reported multiple conditions, indicating a need for health monitoring in Australian combat sports. A number of factors May have influenced engagement with the AMS, including access to the internet, the design of the system, coach views on the system, previous experiences with the system, and the existing culture within Australian combat sports. To increase engagement, there May be a requirement for sports staff to provide relevant feedback on data entered into the system. Until the Barriers are addressed, it is not feasible to implement the system in its current form across a larger cohort of combat athletes.
Description:
Background: There is a risk of concussion when playing rugby union. Appropriate management of concussion includes compliance with the return-to-play regulations of the sports body for reducing the likelihood of premature return-to-play by injured players. Purpose: To describe the proportion of rugby union players who comply with the sports body's regulations on returning to play postconcussion. Study design: Prospective cohort study. Methods: 1958 community rugby union players (aged 15–48 years) in Sydney (Australia) were recruited from schoolboy, grade and suburban competitions and followed over ≥1 playing seasons. Club doctors/physiotherapists/coaches or trained injury recorders who attended the game reported players who sustained a concussion. Concussed players were followed up over a 3-month period and the dates when they returned to play (including either a game or training session) were recorded, as well as any return-to-play advice they received. Results: 187 players sustained ≥1 concussion throughout the follow-up. The median number of days before players returned to play (competition game play or training) following concussion was 3 (range 1–84). Most players (78%) did not receive return-to-play advice postconcussion, and of those who received correct advice, all failed to comply with the 3-week stand-down regulation. Conclusions: The paucity of return-to-play advice received by community rugby union players postconcussion and the high level of non-compliance with return-to-play regulations highlight the need for better dissemination and implementation of the return-to-play regulations and improved understanding of the underlying causes of why players do not adhere to return-to-play practices.
Description:
Methods: Observations and measurements of head dimensions, helmet position, adjustment, and stability were made on 216 motorcyclists. Helmet details were recorded. Participants completed a questionnaire on helmet usability and their riding history. Helmet stability was assessed quasistatically. Results: Differences between the dimensions of ISO headforms and equivalent sized motorcyclists’ heads were observed, especially head width. Almost all (94%) of the helmets were labeled to be compliant with AS/NZS 1698 (2006). The majority of riders were satisfied with the comfort, fit, and usability aspects of their helmets. The majority of helmets were deemed to have been worn correctly. Using quasistatic pull tests, it was found that helmet type (open-face or full-face) and the wearing correctness were among factors that affected the loads at which helmets became displaced. The forces required to displace the helmet were low, around 25 N. Conclusions: The size of the in-use motorcycle helmets did not correspond well to the predicted size based on head dimensions, although motorcyclists were generally satisfied with comfort and fit. The in vivo stability tests appear to overpredict that helmets will come off in a crash, based on the measured forces, tangential forces measured in the oblique impact tests, and the actual rate of helmet ejection. Objectives: One of the main requirements of a protective helmet is to provide and maintain appropriate and adequate coverage to the head. A helmet that is poorly fitted or fastened may become displaced during normal use or even ejected during a crash.
Description:
Riders cycling on roads without bicycle lanes are generally advised to ride in the centre of their lane (primary position), and to move toward the left of the lane (in left-hand traffic; secondary position) only to let faster traffic pass and when it is safe. The present research investigated which situational and personal characteristics were associated with choice of lane position, and whether choice of lane position is associated with on-road crash involvement. A large cohort of bicycle riders from New South Wales Australia reported on their cycling patterns and crashes in 6 reporting weeks over a 1-year period using on-line surveys. During one reporting week 1525 participants identified their preferred choice of lane position in each of 6 visually-depicted scenarios that were designed to investigate the influence of number of lanes (in the cyclists’ direction of travel), parked cars, and bus lanes. A majority of respondents preferred the secondary position in scenarios with a clear kerbside lane. Respondents were significantly more likely to choose the primary position in multiple-lane situations compared to single-lane situations, if there were parked cars in the kerbside lane, and if they were female, younger, experienced riders, transport riders, or high intensity riders. Controlling for personal characteristics, choosing the primary position in a single clear traffic lane scenario was associated with a higher on-road crash rate, while choosing the primary position in a traffic lane with parked cars scenario was associated with a lower on-road crash rate. Results suggested that when riding on-road the bicycle riders in this Australian cohort prefer to keep their distance from motorised traffic, allowing traffic to pass safely when space allows. Nonetheless, results suggested that choice of lane position is highly dependent on the local road and traffic environment. Further research is needed to support advice to cyclists.
Description:
OBJECTIVES: In this study, the incidence of head, neck and facial injuries in youth rugby was determined, and the associated risk factors were assessed. DESIGN: Data were extracted from a cluster randomised controlled trial of headgear with the football teams as the unit of randomisation. No effect was observed for headgear use on injury rates, and the data were pooled. SETTING: General school and club-based community competitive youth rugby in the 2002 and 2003 seasons. PARTICIPANTS: Young male rugby union football players participating in under-13, under 15, under 18 and under 21 years competitions. Eighty-two teams participated in year 1 and 87 in year 2. MAIN OUTCOME MEASURES: Injury rates for all body regions combined, head, neck and face calculated for game and missed game injuries. RESULTS: 554 head, face and neck injuries were recorded within a total of 28 902 h of rugby game exposure. Level of play and player position were related to injury risk. Younger players had the lowest rates of injury; forwards, especially the front row had the highest rate of neck injury; and inside backs had the highest rate of injuries causing the player to miss a game. Contact events, including the scrum and tackle, were the main events leading to injury. CONCLUSION: Injury prevention must focus on the tackle and scrum elements of a youth rugby game.