Consensus Statement on Concussion in Sport: The 3rd International Conference on Concussion in Sport Held in Zurich, November 2008

Abstract

This 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 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 (see Section 11). This document is developed for use by physicians, therapists, certified athletic trainers, health professionals, coaches, and other people 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 judgment on an individualized basis. Readers are encouraged to copy and distribute freely the Zurich Consensus document and the Sports Concussion Assessment Tool (SCAT2) card, and neither is subject to any copyright restriction. The authors request, however, that the document and the SCAT2 card be distributed in their full and complete format.The following focus questions formed the foundation for the Zurich concussion consensus statement:Acute Simple ConcussionRTP IssuesComplex Concussion and Long-Term IssuesPediatric ConcussionFuture DirectionsThe Zurich document additionally examines the management issues raised in the previous Prague and Vienna documents and applies the consensus questions to these areas.Panel discussion regarding the definition of concussion and its separation from mild traumatic brain injury (mTBI) was held. Although there was acknowledgment that the terms refer to different injury constructs and should not be used interchangeably, it was not felt that the panel would define mTBI for the purpose of this document. There was unanimous agreement, however, that concussion is defined as follows:There was unanimous agreement to abandon the “simple” versus “complex” terminology that had been proposed in the Prague agreement statement, as the panel felt that the terminology itself did not fully describe the entities. The panel, however, unanimously retained the concept that the majority (80%–90%) of concussions resolve in a short (7- to 10-day) period, although the recovery time frame may be longer in children and adolescents.2The panel agreed that the diagnosis of acute concussion usually involves the assessment of a range of domains, including clinical symptoms, physical signs, behaviour, balance, sleep, and cognition. 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 SCAT2 form, which is an appendix to this document.The suspected diagnosis of concussion can include one or more of the following clinical domains:If any one or more of these components is present, a concussion should be suspected and the appropriate management strategy instituted.When a player shows ANY features of a concussionIt was unanimously agreed that 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. In some sports, this may require rule change to allow an off-field medical assessment to occur without affecting the flow of the game or unduly penalizing the injured player's team.Sideline evaluation of cognitive function is an essential component in the assessment of this injury. Brief neuropsychological test batteries that assess attention and memory function have been shown to be practical and effective. Such tests include the Maddocks questions3,4 and the Standardized Assessment of Concussion (SAC).5–7 It is worth noting that standard orientation questions (eg, time, place, person) have been shown to be unreliable in the sporting situation when compared with memory assessment.4,8 It is recognized, however, that abbreviated testing paradigms are designed for rapid concussion screening on the sidelines and are not meant to replace comprehensive neuropsychological testing, which is sensitive to detecting subtle deficits that may exist beyond the acute episode, nor should they be used as a stand-alone tool for the ongoing management of sports concussions.It should also be recognized that the appearance of symptoms might be delayed several hours following a concussive episode.An athlete with concussion may be evaluated in the emergency room or doctor's office as a point of first contact following injury or may have been referred from another care provider. In addition to the points outlined above, the key features of this exam should encompa