Consensus Statement on Concussion in Sport: The 4th International Conference on Concussion in Sport, Zurich, November 2012

Abstract

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 4th International Conference on Concussion in Sport held in Zurich, November 2012.1–3The 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 who are primarily involved in the care of injured athletes, whether at the recreational, elite, or professional level.While agreement exists pertaining to principle messages conveyed within this document, the authors acknowledge that the science of concussion is evolving, and therefore, management and 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, the Pocket Concussion Recognition Tool (CRT), the Sports Concussion Assessment Tool version 3 (SCAT3), and the Child SCAT3 card (Appendix), and none 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 the accompanying tools be distributed in their full and complete format.This consensus paper is broken into a number of sections: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.1–3Panel 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 pathologic 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:The majority (80% to 90%) of concussions resolve in a short (7–10 day) period, although the recovery timeframe may be longer in children and adolescents.2The 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 are appendices to this document.The suspected diagnosis of concussion can include 1 or more of the following clinical domains:If any 1 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 concussion: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 appropriate off-field medical assessment to occur without affecting the flow of the game or unduly penalizing the injured player's team. The final determination regarding concussion diagnosis and fitness to play is a medical decision based on clinical judgment.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 SCAT3, which incorporates the Maddocks questions,4,5 and the Standardized Assessment of Concussion (SAC).6–8 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 as