191 research outputs found
Sport concussion assessment tool—fifth edition normative reference values for professional rugby union players
Objective: To describe distributions and establish normative ranges for new or changed subcomponents of the Sports Concussion Assessment Tool (SCAT)-5.
Design: Cross-sectional study.
Setting and Participants: Professional Rugby Union players performing 2017 preseason baseline SCAT-5 testing.
Independent Variables: Subcomponent tests newly introduced or changed in the SCAT-5.
Main Measurements: The 10-word immediate and delayed recall tests and the rapid neurological screen.
Results: Thousand two hundred three players were included in complete case analyses. The 10-word immediate recall test [median score 15, interquartile range (IQR) 15-22, range 3-30] showed an asymmetrical, bimodal distribution. The delayed recall test (median score 7, IQR 5-9, range 0-10) demonstrated a left skewed distribution. The diplopia and reading/following instruction tests of the neurological screen were performed normally by virtually all participants (98.5% and 99.6%, respectively). Normative classification ranges for each SCAT-5 subcomponents of interest were determined.
Conclusions: The increased spread of scores, with improved midrange centering, suggests that the increase to 10-word list lengths should improve the performance of immediate and delayed recall tests. Normative ranges will provide a distribution against which postinjury SCAT-5 scores can be compared and interpreted
Evaluation of World Rugby's concussion management process: results from Rugby World Cup 2015
Objective
To evaluate World Rugby's concussion management process during Rugby World Cup (RWC) 2015.
Design
A prospective, whole population study.
Population
639 international rugby players representing 20 countries.
Method
The concussion management process consisted of 3 time-based, multifaceted stages: an initial on-pitch and/or pitch-side assessment of the injury, a follow-up assessment within 3 hours and an assessment at 36–48 hours. The initial on-pitch assessment targeted obvious signs of concussion, which, if identified, lead to a ‘permanent removal from play’ decision and a diagnosis of concussion. If the on-pitch diagnosis was unclear, a 10-min off-pitch assessment was undertaken for signs and symptoms of concussion leading to a ‘suspected concussion with permanent removal from play’ or a ‘no indication of concussion with return to play’ decision. Evaluations at 3 and 36–48 hours postmatch lead to diagnoses of ‘confirmed concussion’ or ‘no concussion’. Medical staff's decision-making was supported during each stage by real-time video review of events. Players diagnosed with confirmed concussion followed a 5-stage graduated-return-to-play protocol before being allowed to return to training and/or competition.
Results
Players were evaluated for concussion on 49 occasions, of which 24 resulted in diagnoses of concussion. Fourteen players showing on-pitch signs of concussion were permanently removed from play: 4 of the 5 players removed from play following off-pitch medical room evaluation were later diagnosed with a confirmed concussion. Five players not exhibiting in-match signs or symptoms of concussion were later diagnosed with concussion. The overall incidence of concussion during RWC 2015 was 12.5 concussions/1000 player-match-hours.
Conclusions This study supports the implementation of a multimodal, multitime-based concussion evaluation process to ensure that immediate and late developing concussions are captured
Rheological Behavior of Precursor PPV Monolayers
The rheological behavior of different precursor poly(p-phenylene vinylene) (prec-PPV) monolayers at the air-water interface was investigated using an interfacial stress rheometer (ISR). This device nicely reveals a transition of the precursor poly(2,5-dimethoxy-1,4 phenylene vinylene) (prec-DMePPV) monolayer from Newtonian to elastic behavior with increasing surface pressure. The transition is accompanied by an increase in the modulus. This behavior coincides with the coagulation of different 2D condensed domains as revealed by Brewster angle microscopy (BAM). However, partly converted prec-DMePPV monolayers show elastic behavior even at low surface pressures, although a sudden increase of the moduli does occur. This phenomenon is attributed to enhanced hydrophobic interactions between the conjugated moieties in the partly converted polymers. The latter also explains the stretching behavior of the partly converted prec-DMePPV upon transfer in Langmuir-Blodgett-type vertical dipping. The increase of the moduli which is observed is much more gradual in the precursor poly(2,5-dibutoxy-1,4-phenylene vinylene), prec-DBuPPV, a monolayer which is in agreement with the expected expanded state of the latter monolayer.
Long-term survival following traumatic brain injury: a population-based parametric survival analysis
<b><i>Background:</i></b> Long-term mortality may be increased following traumatic brain injury (TBI); however, the degree to which survival could be reduced is unknown. We aimed at modelling life expectancy following post-acute TBI to provide predictions of longevity and quantify differences in survivorship with the general population. <b><i>Methods:</i></b> A population-based retrospective cohort study using data from the Rochester Epidemiology Project (REP) was performed. A random sample of patients from Olmsted County, Minnesota with a confirmed TBI between 1987 and 2000 was identified and vital status determined in 2013. Parametric survival modelling was then used to develop a model to predict life expectancy following TBI conditional on age at injury. Survivorship following TBI was also compared with the general population and age- and gender-matched non-head injured REP controls. <b><i>Results:</i></b> Seven hundred and sixty nine patients were included in complete case analyses. The median follow-up time was 16.1 years (interquartile range 9.0-20.4) with 120 deaths occurring in the cohort during the study period. Survival after acute TBI was well represented by a Gompertz distribution. Victims of TBI surviving for at least 6 months post-injury demonstrated a much higher ongoing mortality rate compared to the US general population and non-TBI controls (hazard ratio 1.47, 95% CI 1.15-1.87). US general population cohort life table data was used to update the Gompertz model's shape and scale parameters to account for cohort effects and allow prediction of life expectancy in contemporary TBI. <b><i>Conclusions:</i></b> Survivors of TBI have decreased life expectancy compared to the general population. This may be secondary to the head injury itself or result from patient characteristics associated with both the propensity for TBI and increased early mortality. Post-TBI life expectancy estimates may be useful to guide prognosis, in public health planning, for actuarial applications and in the extrapolation of outcomes for TBI economic models
King-Devick concussion test performs poorly as a screening tool in elite rugby union players: a prospective cohort study of two screening tests versus a clinical reference standard
BACKGROUND: The King-Devick (KD) test is an objective clinical test of eye movements that has been used to screen for concussion. We characterised the accuracy of the KD test and the World Rugby Head Injury Assessment (HIA-1) screening tools as methods of off-field evaluation for concussion after a suspicious head impact event. METHODS: A prospective cohort study was performed in elite English rugby union competitions between September 2016 and May 2017. The study population comprised consecutive players identified with a head impact event with the potential to result in concussion. The KD test was administered off-field, alongside the World Rugby HIA-1 screening tool, and the results were compared with the preseason baseline. Accuracy was measured against a reference standard of confirmed concussion, based on the clinical judgement of the team doctor after serial assessments. RESULTS: 145 head injury events requiring off-field medical room screening assessments were included in the primary analysis. The KD test demonstrated a sensitivity of 60% (95% CI 49.0 to 70) and a specificity of 39% (95% CI 26 to 54) in identifying players subsequently diagnosed with concussion. Area under the receiver operating characteristic curve for prolonged KD test times was 0.51 (95% CI 0.41 to 0.61). The World Rugby HIA-1 off-field screening tool sensitivity did not differ significantly from the KD test (sensitivity 75%, 95% CI 66 to 83, P=0.08), but specificity was significantly higher (91%, 95% CI 82 to 97, P<0.001). Although combining the KD test and the World Rugby HIA-1 multimodal screening assessment achieved a significantly higher sensitivity of 93% (95% CI 86% to 97%), there was a significantly lower specificity of 33% (95% CI 21% to 48%), compared with the HIA-1 test alone. CONCLUSIONS: The KD test demonstrated limited accuracy as a stand-alone remove-from-play sideline screening test for concussion. As expected with the addition of any parallel test, combination of the KD test with the HIA-1 off-field screening tool provided improved sensitivity in identifying concussion, but at the expense of markedly lower specificity. These results suggest that it is unlikely that the KD test will be incorporated into multimodal off-field screening assessments for concussion at the present time
A video analysis of head injuries satisfying the criteria for a head injury assessment in professional Rugby Union: a prospective cohort study
Objectives
Concussion is the most common match
injury in professional Rugby Union, accounting for 25%
of match injuries. The primary prevention of head injuries
requires that the injury mechanism be known so that
interventions can be targeted to specifically overall
incidence by focusing on characteristics with the greatest
propensity to cause a head injury.
Methods
611 head injury assessment (HIA) events
in professional Rugby Union over a 3-year period were
analysed, with specific reference to match events,
position, time and nature of head contact.
Results
464 (76%) of HIA events occur during
tackles, with the tackler experiencing a significantly
greater propensity for an HIA than the ball carrier (1.40
HIAs/1000 tackles for the tackler vs 0.54 HIAs/1000
tackles for the ball carrier, incidence rate ratio (IRR)
2.59). Propensity was significantly greater for backline
players than forwards (IRR 1.54, 95%CI 1.28 to 1.84),
but did not increase over the course of the match. Head
to head contact accounted for the most tackler HIAs,
with the greatest propensity.
Conclusions
By virtue of its high propensity
and frequency, the tackle should be the focus for
interventions that may include law change and technique
education. A specific investigation of the characteristics
of the tackle is warranted to refine the approach to
preventative strategies
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
UK monitoring and deposition of tephra from the May 2011 eruption of Grímsvötn, Iceland
Mapping the transport and deposition of tephra is important for the assessment of an eruption’s impact on health, transport, vegetation and infrastructure, but it is challenging at large distances from a volcano (> 1000 km), where it may not be visible to the naked eye. Here we describe a range of methods used to quantify tephra deposition and impact on air quality during the 21–28 May 2011 explosive basaltic eruption of Grímsvötn volcano, Iceland. Tephra was detected in the UK with tape-on-paper samples, rainwater samples, rainwater chemistry analysis, pollen slides and air quality measurements. Combined results show that deposition was mainly in Scotland, on 23–25 May. Deposition was patchy, with adjacent locations recording different results. Tape-on-paper samples, collected by volunteer citizen scientists, and giving excellent coverage across the UK, showed deposition at latitudes >55°N, mainly on 24 May. Rainwater samples contained ash grains mostly 20–30 μm long (maximum recorded grainsize 80 μm) with loadings of up to 116 grainscm-2. Analysis of rainwater chemistry showed high concentrations of dissolved Fe and Al in samples from N Scotland on 24–27 May. Pollen slides recorded small glass shards (3–4 μm long) deposited during rainfall on 24–25 May and again on 27 May. Air quality monitoring detected increased particulate matter concentrations in many parts of the country. An hourly concentration of particles 53°N) on 24 May but no negative effects on health were reported. Although the eruption column reached altitudes of 20 km above sea level, air mass trajectories suggest that only tephra from the lowest 4 km above sea level of the eruption plume was transported to the UK. This demonstrates that even low plumes could deliver tephra to the UK and suggests that the relative lack of basaltic tephra in the tephrochronological record is not due to transport processes
Sport Concussion Assessment Tool : baseline and clinical reference limits for concussion diagnosis and management in elite Rugby Union
Objectives
Rugby Union has adapted the Sports Concussion Assessment Tool (SCAT) into an abridged off-field concussion screen and the complete SCAT is used during diagnostic screens performed after head impact events. No firm guidelines exist as to what should be considered “abnormal” and warrant further evaluation. This study evaluates SCAT performances in 13,479 baseline SCAT assessments, and proposes clear reference limits for each sub-component of the SCAT5. Baseline reference limits are proposed to guide management of baseline testing by identifying abnormal sub-tests, enhancing the clinical validity of baseline screens, while clinical reference limits are identified to support concussion diagnosis when no baseline is available.
Design
Cross sectional census sample.
Methods
13,479 baseline SCATs from 7565 elite male rugby players were evaluated. Baseline reference limits were identified for each sub-test as the sub-test result achieved by approximately 5% of the population, while clinical references limits corresponded to the sub-test score achieved by as close as possible to 50% of the cohort.
Results
Players reported symptoms 35% (95% CI 1.29–1.42) more frequently during SCAT5 than SCAT3 baseline assessments (mean 1.4 ± 2.7 vs 1.0 ± 2.4). Ceiling effects were identified for many cognitive sub-tests within the SCAT. Baseline and Clinical reference limits corresponding to the worst performing 5th percentile and 50th percentile were described.
Conclusions
Targeted baseline re-testing should be repeated when abnormal sub-tests are identified according to proposed baseline reference limits, while a more conservative clinical reference limit supports concussion diagnosis during screens in diagnostic settings
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