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British Journal of Sports Medicine | 2013

Consensus statement on concussion in sport: the 4th International Conference on Concussion in Sport held in Zurich, November 2012

Paul McCrory; Willem H. Meeuwisse; Mark Aubry; Bob Cantu; Ruben J. Echemendia; Lars Engebretsen; Karen M. Johnston; Jeffrey S. Kutcher; Martin Raftery; Allen K. Sills; Brian W. Benson; Gavin A. Davis; Richard G. Ellenbogen; Kevin M. Guskiewicz; Grant L. Iverson; Barry D. Jordan; James Kissick; Michael McCrea; Andrew S. McIntosh; David Maddocks; Michael Makdissi; Laura Purcell; Margot Putukian; Kathryn Schneider; Charles H. Tator; Michael J. Turner

This paper is a revision and update of the recommendations developed following the 1st (Vienna 2001), 2nd (Prague 2004) and 3rd (Zurich 2008) International Consensus Conferences on Concussion in Sport and is based on the deliberations at the 4th International Conference on Concussion in Sport held in Zurich, November 2012.1–3 The new 2012 Zurich Consensus statement is designed to build on the principles outlined in the previous documents and to develop further conceptual understanding of this problem using a formal consensus-based approach. A detailed description of the consensus process is outlined at the end of this document under the Background section. This document is developed primarily for use by physicians and healthcare professionals who are involved in the care of injured athletes, whether at the recreational, elite or professional level. While agreement exists pertaining to principal messages conveyed within this document, the authors acknowledge that the science of concussion is evolving, and therefore management and return to play (RTP) decisions remain in the realm of clinical judgement on an individualised basis. Readers are encouraged to copy and distribute freely the Zurich Consensus document, the Concussion Recognition Tool (CRT), the Sports Concussion Assessment Tool V.3 (SCAT3) and/or the Child SCAT3 card and none are subject to any restrictions, provided they are not altered in any way or converted to a digital format. The authors request that the document and/or the accompanying tools be distributed in their full and complete format. This consensus paper is broken into a number of sections 1. A summary of concussion and its management, with updates from the previous meetings; 2. Background information about the consensus meeting process; 3. A summary of the specific consensus questions discussed at this meeting; 4. The Consensus paper should be read in conjunction with the SCAT3 assessment tool, the Child SCAT3 and the CRT …


British Journal of Sports Medicine | 2005

Summary and agreement statement of the 2nd International Conference on Concussion in Sport, Prague 2004

Paul McCrory; Karen M. Johnston; Willem H. Meeuwisse; Mark Aubry; Robert C. Cantu; Jiri Dvorak; Toni Graf-Baumann; James P. Kelly; Mark R. Lovell; Patrick Schamasch

In November 2001, the 1st International Symposium on Concussion in Sport was held in Vienna, Austria to provide recommendations for the improvement of safety and health of athletes who suffer concussive injuries in ice hockey, football (soccer), and other sports. The 2nd International Symposium on Concussion in Sport was organised by the same group and held in Prague, Czech Republic in November 2004. It resulted in a revision and update of the Vienna consensus recommendations, which are presented here.


Clinical Journal of Sport Medicine | 2009

Consensus statement on Concussion in Sport 3rd International Conference on Concussion in Sport held in Zurich, November 2008.

Paul McCrory; Willem Meeuwisse; Karen M. Johnston; Jiri Dvorak; Mark Aubry; Mick Molloy; Robert Cantu

PreambleThis paper is a revision and update of the recommendations developed following the 1st (Vienna) and 2nd (Prague) International Symposia on Concussion in Sport.1,2 The Zurich Consensus statement is designed to build on the principles outlined in the original Vienna and Prague documents and to


British Journal of Sports Medicine | 2002

Summary and agreement statement of the first International Conference on Concussion in Sport, Vienna 2001

Mark Aubry; Robert C. Cantu; Jiri Dvorak; Toni Graf-Baumann; Karen M. Johnston; James P. Kelly; Mark R. Lovell; Paul McCrory; Willem H. Meeuwisse; Patrick Schamasch

Recommendations for the improvement of safety and health of athletes who may suffer concussive injuries In November 2001, the first International Symposium on Concussion in Sport was held in Vienna, Austria. This symposium was organised by the International Ice Hockey Federation (IIHF), the Federation Internationale de Football Association Medical Assessment and Research Centre (FIFA, F-MARC), and the International Olympic Committee Medical Commission (IOC). The aim of the symposium was to provide recommendations for the improvement of safety and health of athletes who suffer concussive injuries in ice hockey, football (soccer), and other sports. To this end a range of experts were invited to address specific issues of epidemiology, basic and clinical science, grading systems, cognitive assessment, new research methods, protective equipment, management, prevention, and long term outcome, and to discuss a unitary model for understanding concussive injury. At the conclusion of the conference, a small group of experts were given a mandate by the conference delegates and organising bodies to draft a document describing the agreement position reached by those in attendance at that meeting. For the purpose of this paper, this group will be called the Concussion in Sport Group (CISG). This review seeks to summarise the findings of the Vienna conference and to provide a working document that will be widely applicable to sport related concussion. This document is developed for use by doctors, therapists, health professionals, coaches, and other people involved in the care of injured athletes, whether at the recreational, elite, or professional level. During the course of the symposium, a persuasive argument was made that a comprehensive systematic approach to concussion would be of potential benefit to aid the injured athlete and direct management decisions.1 This protocol represents a work in progress, and, as with all other guidelines or proposals, it must undergo revision …


Applied Neuropsychology | 2006

Measurement of Symptoms Following Sports-Related Concussion: Reliability and Normative Data for the Post-Concussion Scale

Mark R. Lovell; Grant L. Iverson; Michael W. Collins; Kenneth Podell; Karen M. Johnston; Dustin A. Pardini; Jamie E. Pardini; John Norwig; Joseph C. Maroon

It is important to carefully evaluate self-reported symptoms in athletes with known or suspected concussions. This article presents data on the psychometric and clinical properties of a commonly used concussion symptom inventory-the Post-Concussion Scale. Normative and psychometric data are presented for large samples of young men (N = 1,391) and young women (N = 355). In addition, data gathered from a concussed sample of athletes (N = 260) seen within 5 days of injury are presented. These groups represent samples of both high school and collegiate athletes. Data from a subsample of 52 concussed athletes seen 3 times post-injury are presented to illustrate symptom reporting patterns during the initial recovery period. General guidelines for the clinical use of the scale are provided.


Clinical Journal of Sport Medicine | 2002

Concussions among university football and soccer players

J. Scott Delaney; Vincent J. Lacroix; Suzanne Leclerc; Karen M. Johnston

ObjectiveA study to examine the incidence and characteristics of concussions among Canadian university athletes during 1 full year of football and soccer participation. DesignRetrospective survey. ParticipantsThree hundred eighty Canadian university football and 240 Canadian university soccer players reporting to 1999 fall training camp. Of these, 328 football and 201 soccer players returned a completed questionnaire. Main Outcome MeasuresBased on self-reported symptoms, calculations were made to determine the number of concussions experienced during the previous full year of football or soccer participation, the duration of symptoms, the time for return to play, and any associated risk factors for concussions. ResultsOf all the athletes who returned completed questionnaires, 70.4% of the football players and 62.7% of the soccer players had experienced symptoms of a concussion during the previous year. Only 23.4% of the concussed football players and 19.8% of the concussed soccer players realized they had suffered a concussion. More than one concussion was experienced by 84.6% of the concussed football players and 81.7% of the concussed soccer players. Examining symptom duration, 27.6% of all concussed football players and 18.8% of all concussed soccer players experienced symptoms for at least 1 day or longer. Tight end and defensive lineman were the positions most commonly affected in football, while goalies were the players most commonly affected in soccer. Variables that increased the odds of suffering a concussion during the previous year for football players included a history of a traumatic loss of consciousness or a recognized concussion in the past. Variables that increased the odds of suffering a concussion during the previous year for soccer players included a past history of a recognized concussion while playing soccer and being female. ConclusionsUniversity football and soccer players seem to be experiencing a significant amount of concussions while participating in their respective sports. Variables that seem to increase the odds of suffering a concussion during the previous year for football and soccer players include a history of a recognized concussion. Despite being relatively common, symptoms of concussion may not be recognized by many players.


NeuroImage | 2004

Functional abnormalities in symptomatic concussed athletes: an fMRI study.

J.-K Chen; Karen M. Johnston; Stephen Frey; Michael Petrides; Keith J. Worsley; Alain Ptito

Our aim was to quantify with functional magnetic resonance imaging (fMRI) changes in brain activity in concussed athletes and compare the results with those of normal control subjects. Regional brain activations associated with a working memory task were obtained from a group of concussed athletes (15 symptomatic, 1 asymptomatic) and eight matched control subjects, using blood oxygen level dependent (BOLD) fMRI. The average percent signal change from baseline to working memory condition in each region of interest was computed. Symptomatic concussed athletes demonstrated task-related activations in some but not all the regions of interest, even when they performed as well as the control subjects. Furthermore, several concussed athletes had additional increases in activity outside the regions of interest, not seen in the control group. Quantitative analysis of BOLD signals within regions of interest revealed that, in general, concussed athletes had different BOLD responses compared to the control subjects. The task-related activation pattern of the one symptom-free athlete was comparable to that of the control group. We also repeated the study in one athlete whose symptoms had resolved. On the first study, when he was still symptomatic, less task-related activations were observed. On follow-up, once his symptoms had disappeared, the task-related activations became comparable to those of the control group. These results demonstrate the potential of fMRI, in conjunction with the working memory task, to identify an underlying pathology in symptomatic concussed individuals with normal structural imaging results.


American Journal of Sports Medicine | 2004

Grade 1 or “Ding” Concussions in High School Athletes:

Mark R. Lovell; Michael W. Collins; Grant L. Iverson; Karen M. Johnston; James P. Bradley

Background Recent concussion management guidelines have suggested that athletes with mild (grade 1) concussions may be returned to play if asymptomatic for 15 minutes. The purpose of this study was to assess the utility of a current concussion management guideline in classifying and managing mild concussion. Hypothesis High school athletes diagnosed with a grade 1 concussion will demonstrate measurable decline in neuropsychological functioning that persists during the 1st week of recovery. Study Design Prospective study designed to evaluate neuropsychological functioning both prior to and following concussion. Methods Forty-three high school athletes completed neuropsychological test performance and symptom ratings prior to the season and at two times during the 1st week following mild concussion. Results Thirty-six hours after injury, mildly concussed high school athletes demonstrated a decline in memory (P < 0.003) and a dramatic increase in self-reported symptoms (P < 0.00001) compared to baseline performance. Conclusions Athletes with grade 1 concussion demonstrated memory deficits and symptoms that persisted beyond the context in which they were injured. These data suggest that current grade 1 return-to-play recommendations that allow for immediate return to play may be too liberal. Clinical Relevance A reconsideration of current concussion grading systems appears to be warranted.


Clinical Journal of Sport Medicine | 2002

Summary and agreement statement of the 1st International Symposium on Concussion in Sport, Vienna 2001.

Mark Aubry; Robert C. Cantu; Jiri Dvorak; Toni Graf-Baumann; Karen M. Johnston; James P. Kelly; Mark R. Lovell; Paul McCrory; Willem H. Meeuwisse; Patrick Schamasch

BACKGROUNDIn November 2001, the 1st International Symposium on Concussion in Sport was held in Vienna, Austria. This symposium was organized by the International Ice Hockey Federation (IIHF), the Federation Internationale de Football Association Medical Assessment and Research Centre (FIFA, F-MARC),


American Journal of Sports Medicine | 2003

Relationship Between Postconcussion Headache and Neuropsychological Test Performance in High School Athletes

Michael W. Collins; Melvin Field; Mark R. Lovell; Grant L. Iverson; Karen M. Johnston; Joseph C. Maroon; Freddie H. Fu

Background: The relevance of headache to outcome after sports-related concussion is poorly understood. Hypotheses: High school athletes reporting headache approximately 1 week after injury will have significantly more other concussion symptoms and will perform more poorly on neuropsychological tests than athletes not experiencing headache. Study Design: Prospective cohort study. Methods: Study participants included 109 high school athletes who had sustained concussion and who were divided into two groups: those reporting headache 7 days after injury and those reporting no headaches. The two groups were compared regarding on-field markers of concussion severity at the time of injury and symptoms and neurocognitive test results collected via ImPACT, a computerized neuropsychological test battery and postconcussion symptom scale, at a mean of 6.8 days after injury. Results: Athletes reporting posttraumatic headache demonstrated significantly worse performance on reaction time and memory ImPACT neurocognitive composite scores. These athletes also reported significantly more symptoms other than headache and were more likely to have demonstrated on-field anterograde amnesia. Conclusions: Findings suggest that any degree of postconcussion headache in high school athletes 7 days after injury is likely associated with an incomplete recovery after concussion.

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Paul McCrory

Florey Institute of Neuroscience and Mental Health

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Mark Aubry

International Olympic Committee

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Alain Ptito

McGill University Health Centre

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Grant L. Iverson

Spaulding Rehabilitation Hospital

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Mark R. Lovell

University of Pittsburgh

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Jiri Dvorak

Fédération Internationale de Football Association

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Gavin A. Davis

Florey Institute of Neuroscience and Mental Health

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