Consensus Statement on Concussion in Sport—the 4th International Conference on Concussion in Sport Held in Zurich, November 2012

Abstract

Preamble 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 Conference on Concussion in Sport and is based on the deliberations at the 4thInternational 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 for use by physicians and health care professionals primarily 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 decisions remain in the realm of clinical judgment on an individualized basis. Readers are encouraged to copy and distribute freely the Zurich Consensus document, the Concussion Recognition Tool (CRT), the Sport Concussion Assessment Tool version 3 (SCAT3), and/or the Child-SCAT3 card and neither is subject to any restriction, provided it is 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: (a) A summary of concussion and its management, with updates from the previous meetings. (b) Background information about the consensus meeting process. (c) A summary of the specific consensus questions discussed at this meeting. (d) The Consensus paper should be read in conjunction with the SCAT3 assessment tool, the Child-SCAT3 and the Concussion Recognition Tool (designed for lay use). SECTION 1: SPORT CONCUSSION AND ITS MANAGEMENT The Zurich 2012 document examines sport concussion and management issues raised in the previous Vienna 2001, Prague 2004, and Zurich 2008 documents and applies the consensus questions from Section 3 to these areas.1–3 Definition of Concussion Panel discussion regarding the definition of concussion and its separation from mild traumatic brain injury (mTBI) was held. There was acknowledgement by the Concussion in Sport Group (CISG) that although the terms mild traumatic brain injury (mTBI) and concussion are often used interchangeably in the sporting context and particularly in the US literature, others use the term to refer to different injury constructs. Concussion is the historical term representing low velocity injuries that cause brain “shaking” resulting in clinical symptoms and which are not necessarily related to a pathological injury. Concussion is a subset of TBI and the term concussion will be used in this document. It was also noted that the term commotio cerebri is often used in European and other countries. Minor revisions were made to the definition of concussion and it is defined as follows: Concussion is a brain injury and is defined as a complex pathophysiological process affecting the brain, induced by biomechanical forces. Several common features that incorporate clinical, pathologic and biomechanical injury constructs that may be utilized in defining the nature of a concussive head injury include: Concussion may be caused either by a direct blow to the head, face, neck or elsewhere on the body with an “impulsive” force transmitted to the head. Concussion typically results in the rapid onset of short-lived impairment of neurologic function that resolves spontaneously. However in some cases, symptoms and signs may evolve over a number of minutes to hours. Concussion may result in neuropathological changes, but the acute clinical symptoms largely reflect a functional disturbance rather than a structural injury and, as such, no abnormality is seen on standard structural neuroimaging studies. Concussion results in a graded set of clinical symptoms that may or may not involve loss of consciousness. Resolution of the clinical and cognitive symptoms typically follows a sequential course. However, it is important to note that in some cases symptoms may be prolonged. Recovery of Concussion The majority (80%-90%) of concussions resolve in a short (7-10 day) period, although the recovery time frame may be longer in children and adolescents.2 Symptoms and Signs of Acute Concussion The diagnosis of acute concussion usually involves the assessment of a range of domains including clinical symptoms, physical signs, cognitive impairment, neurobehavioral features, and sleep disturbance. Furthermore, a detailed concussion history is an important part of the evaluation both in the injured athlete and when conducting a preparticipation examination. The detailed clinical assessment of concussion is outlined in the SCAT3 and Child-SCAT3 forms, which is an appendix to this document. The suspected diagnosis of concussion can include 1 or more of the following clinical domains: (a) Symptoms - somatic (eg, headache), cognitive (eg, feeling like in a fog) and/or emotional symptoms (eg, lability) (b) Physical signs (eg, loss of consciousness, amnesia) (c) Behavioural changes (eg, irritability) (d) Cognitive impairment (eg, slowed reaction times) (e) Sleep disturbance (eg, insomnia) If any 1 or more of these components is present, a concussion should be suspected and the appropriate management strategy instituted. On-Field or Sideline Evaluation of Acute Concussion When a player shows ANY features of a concussion: (a) The player should be evaluated by a physician or other licensed healthcare provider onsite using standard emergency management principles and particular attention should be given to excluding a cervical spine injury. (b) The appropriate disposition of the player must be determined by the treating healthcare provider in a timely manner. If no healthcare provider is available, the player should be safely removed from practice or play and urgent referral to a physician arranged. (c) Once the first aid issues are addressed, then an assessment of the concussive injury should be made using the SCAT3 or other sideline assessment tools. (d) The player should not be left alone following the injury and serial monitoring for deterioration is essential over the initial few hours following injury. (e) A player with diagnosed concussion should not be allowed to return to play on the day of injury. Sufficient time for assessment and adequate facilities should be provided for the appropriate medical assessment both on and off the field for all injured athletes. 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This may involve information from and to the injury. 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This may be a particular in and head injury are often than in in Sport The nature of sport that it to play and should not be However, sporting should be encouraged to that may concussion play and should be as of the to or the of concussive injury the is of athletes, and the is a of in this and health care must be regarding the of its clinical features, assessment and principles of return to to including and are important in the In concussion the and of sport as International International and International who this and must be play and for are that should be encouraged in all and sporting and play an important part in these are on the field of SECTION In November 2001, the 1st International Conference on Concussion in Sport was held in This meeting was by the in with and the of the part of the resulting for the the for and updates were The 2nd International Conference on Concussion in Sport was by the with the of the and was held in in November The of the were to recommendations for the of and health of who concussive injuries in as as other this a range of were to both to specific issues of and clinical injury cognitive new management, and The 3rd International Conference on Concussion in Sport was held in Zurich, on 2008 and was designed as a formal consensus meeting following the set by the US of of the consensus can be The principles the of a consensus are A was to and attention to the Panel with or of and in clinical and in a by and The then in an to the consensus A number of specific questions were and in to the and the of the The of the was to to these questions are outlined A was and in for use by the in the The consensus statement is to as the of the The consensus statement will be to on both health care practice and medical The not with any The was for the consensus and the were from clinical and in the field of not but were for their and understanding of this The International Conference on Concussion in Sport was held in Zurich, on November 2012 and the as for the 3rd meeting. consensus and authors were to an for of of information related to authors and of will be made on the and with the This consensus document the of and will to be to the of new It an of issues that may be of to healthcare involved in the management of It is not as a standard of and should not be as This document is a and is of a with the practice of a healthcare will on the and specific to It is that this document will be and to SECTION 2012 that is the subject of a that is in the of all and of will be in When an athlete and not is a cognitive injury the of concussion in a The consensus that concussion is an evolving injury in the acute with clinical signs and symptoms, which may reflect the injury in the Concussion is to be the complex injuries in sport to and The majority of concussions in sport occur loss of or neurologic present, is no or that can on for an diagnosis of concussion in the sporting of this evolving it is not to rule concussion when an injury 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