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

• DOI: 10.1097/jsm.0b013e31828b67cf
• Publication Date: 2013-03-12T12:31:33Z
• Authors: Paul McCrory; Willem Meeuwisse; Mark Aubry; Bob Cantu; Jiri Dvorak; Ruben J. Echemendia; Lars Engebretsen; Karen Johnston; Jeffrey S. Kutcher; Martin Raftery; Allen Sills
• Keywords: Statement (logic)

Preamble This paper is a revision and update of the recommendations developed following 1st (Vienna 2001), 2nd (Prague 2004) 3rd (Zurich 2008) International Consensus Conference on Concussion in Sport based deliberations at 4thInternational On In held Zurich, November 2012.1–3 The new 2012 Zurich statement designed to build principles outlined previous documents develop further conceptual understanding this problem using formal consensus-based approach. A detailed description consensus process end document under "background" section. for use by physicians health care professionals primarily who are involved injured athletes, whether recreational, elite, or professional level. While agreement exists pertaining principal messages conveyed within document, authors acknowledge that science concussion evolving therefore management return play decisions remain realm clinical judgment an individualized basis. Readers encouraged copy distribute freely Recognition Tool (CRT), Assessment version 3 (SCAT3), and/or Child-SCAT3 card neither subject any restriction, provided it not altered way converted digital format. authors' request accompanying tools be distributed their full complete broken into number sections: (a) summary its management, with updates from meetings. (b) Background information about meeting process. (c) specific questions discussed meeting. (d) should read conjunction SCAT3 assessment tool, (designed lay use). SECTION 1: SPORT CONCUSSION AND ITS MANAGEMENT examines sport issues raised Vienna 2001, Prague 2004, 2008 applies Section these areas.1–3 Definition Panel discussion regarding definition separation mild traumatic brain injury (mTBI) was held. There acknowledgement Group (CISG) although terms often used interchangeably sporting context particularly US literature, others term refer different constructs. historical representing low velocity injuries cause "shaking" resulting symptoms which necessarily related pathological injury. subset TBI will document. It also noted commotio cerebri European other countries. Minor revisions were made defined as follows: complex pathophysiological affecting brain, induced biomechanical forces. Several common features incorporate clinical, pathologic constructs may utilized defining nature concussive head include: caused either direct blow head, face, neck elsewhere body "impulsive" force transmitted head. typically results rapid onset short-lived impairment neurologic function resolves spontaneously. However some cases, signs evolve over minutes hours. result neuropathological changes, but acute largely reflect functional disturbance rather than structural and, such, no abnormality seen standard neuroimaging studies. graded set involve loss consciousness. Resolution cognitive follows sequential course. However, important note cases prolonged. Recovery majority (80%-90%) concussions resolve short (7-10 day) period, recovery time frame longer children adolescents.2 Symptoms Signs Acute diagnosis usually involves range domains including symptoms, physical signs, impairment, neurobehavioral features, sleep disturbance. Furthermore, history part evaluation both athlete when conducting preparticipation examination. forms, appendix suspected can include 1 more domains: - somatic (eg, headache), feeling like fog) emotional lability) Physical consciousness, amnesia) Behavioural changes irritability) Cognitive slowed reaction times) (e) Sleep insomnia) If components present, appropriate strategy instituted. On-Field Sideline Evaluation When player shows ANY concussion: evaluated physician licensed healthcare provider onsite emergency particular attention given excluding cervical spine disposition must determined treating timely manner. available, safely removed practice urgent referral arranged. Once first aid addressed, then sideline tools. left alone serial monitoring deterioration essential initial few hours diagnosed allowed day Sufficient adequate facilities medical off field all athletes. sports, require rule change allow off-field occur without flow game unduly penalizing player's team. final determination fitness decision judgment. component Brief neuropsychological test batteries assess memory have been shown practical effective. Such tests SCAT3, incorporates Maddocks questions4,5 Standardized (SAC).6–8 worth noting orientation time, place, person) unreliable situation compared assessment.5,9 recognized, however, abbreviated testing paradigms screening sidelines meant replace comprehensive ideally performed trained neuropsychologists sensitive subtle deficits exist beyond episode; nor they stand-alone tool ongoing sports concussions. recognized appearance deficit might delayed several episode stage. Emergency Room Office Medical Personnel An room doctor's office point contact referred another provider. addition points above, key exam encompass: neurological examination thorough mental status, functioning, gait, balance. status patient, there has improvement since seeking additional parents, coaches, teammates, eyewitness need emergent order exclude severe involving large part, above included assessment. Investigations investigations assist exclusion Conventional normal Given caveat, suggestions made: Brain CT (or where available MR scan) contributes little employed whenever suspicion intra-cerebral lesion skull fracture) exists. Examples such situations prolonged conscious state, focal deficit, worsening symptoms. Other imaging modalities fMRI demonstrate activation patterns correlate symptom severity concussion.10–14 Whilst routine present nevertheless provide insight mechanisms. Alternative technologies positron emission tomography, diffusion tensor imaging, magnetic resonance spectroscopy, connectivity), while demonstrating compelling findings, still early stages development cannot recommended research setting. Published studies, sophisticated plate technology, well those less balance Balance Error Scoring System [BESS]), identified postural stability lasting approximately 72 sport-related concussion. appears provides useful objectively assessing motor domain considered reliable valid athletes suffering concussion, indicate component.15–21 significance Apolipoprotein (Apo) E4, ApoE promotor gene, Tau polymerase, genetic markers risk outcome unclear time.22,23 Evidence human animal studies induction variety cytokine factors as: insulin-like growth factor-1 (IGF-1), IGF binding protein-2, Fibroblast factor, Cu-Zn superoxide dismutase, dismutase -1 (SOD-1), nerve glial fibrillary acidic protein (GFAP), S-100. How affected known stage.24–31 addition, biochemical serum cerebral spinal fluid biomarkers [including S-100, neuron enolase (NSE), myelin basic (MBP), GFAP, tau, etc] proposed means cellular damage detected if present.32–38 currently insufficient evidence, justify clinically. Different electrophysiological recording techniques evoked response potential [ERP], cortical stimulation, electroencephalography) demonstrated reproducible abnormalities postconcussive state; however reliably differentiated concussed controls.39–45 remains established. Neuropsychological application (NP) value significant evaluation.46–51 Although most overlaps course recovery, occasionally precede commonly follow resolution, suggesting overall particular, protocol.52,53 emphasized NP sole basis decisions. Rather, decision-making assessments investigational results. (including function) management. normally done computerized Formal required necessary neuropsychologist. best position interpret virtue background training, ultimate one multidisciplinary approach, possible, taken. absence assessment) testing, conservative approach appropriate. clinically asymptomatic, add injury.54,55 determining aspects eg, school pediatric athlete. consultation neuropsychologist.56,57 Baseline panel felt mandatory aspect every helpful interpretation tests. educative opportunity discuss At evidence recommend widespread baseline testing. Management cornerstone rest until program exertion prior clearance play. current published evaluating effect sparse. period symptomatic (24-48 hours) benefit. Further evaluate long-term rest, optimal amount type needed. evidence-based recommendations, sensible gradual social activities (prior sports) manner does exacerbation Low-level exercise slow recover benefit, timing initiation treatment unknown. As described spontaneously days. situations, expected proceed progressively through stepwise strategy.58 Graduated Return Play Protocol (RTP) protocol Table 1.TABLE ProtocolWith progression, continue next level asymptomatic Generally, each step take 24 so would week rehabilitation once provocative exercise. postconcussion patient drop back try progress again after 24-hour passed. Same Day RTP unanimously agreed occur. data collegiate high level, same postinjury evident likely symptoms.59–65 'Difficult' Persistently Symptomatic Patient Persistent (>10 days) generally reported 10%-15% general, consider pathologies. Cases falls outside window (ie, 10 managed providers experience sports-related Psychological Mental Health Issues approaches injury, modifiers listed below.66,67 Physicians affective depression anxiety, forms injury.58 Role Pharmacological Therapy therapy applied 2 distinct situations. disturbance, etc). second drug modify underlying pathophysiology condition aim shortening duration symptoms.68 broad terms, only clinicians experienced consideration free, taking pharmacological agents/medications mask Where antidepressant commenced during medication carefully clinician. Preparticipation Recognizing importance history, appreciating fact many recognize suffered past, value.69–72 preidentify fit high-risk category educate regard structured length just perceived past dependence upon recall teammates coaches unreliable.69 injuries, relevance. emphasizing setting maxillofacial coexistent missed unless specifically assessed. Questions disproportionate impact versus matching alert clinician increasing vulnerability advised details protective equipment sought, recent remote injuries. unrecognized benefit insofar allows concerned modification playing behavior required. Modifying Factors 'modifying' influence investigation predict persistent efficacy limited. These 2.TABLE 2: ModifiersFemale Gender role female gender possible modifier panel. unanimous conclusive enough modifying accepted factor severity.73–75 Significance Loss Consciousness (LOC) moderate LOC acknowledged predictor outcome.76 findings describe associated deficits, measure severity.77,78 (>1 minute duration) Amnesia renewed interest posttraumatic amnesia surrogate severity.64,79,80 suggests nature, burden, presence alone.77,81,82 retrograde varies measurement hence poorly reflective severity.83,84 Motor Convulsive Phenomena immediate phenomena tonic posturing) convulsive movements accompany dramatic, benign injury.85,86 Depression (such depression) consequence levels Neuroimaging suggest depressed mood consistent limbic-frontal model depression.34,87–97 multifactorial patients. SPECIAL POPULATIONS Child Adolescent Athlete contained herein adolescents down age 13 years. Below age, report adults age-appropriate checklists child adolescent parent input, possibly teacher input appropriate.98–104 (see Appendix II) subjects aged 5 12 broadly adult paradigm differences. Timing differ planning home developmentally late teen years due maturation occurs which, turn, makes utility comparison person's own performance population norms limited.20 group paediatric data, learning disorders ADHD strategies.56,57,98 activity before child/adolescent successfully. concept 'cognitive rest' highlighted special reference child's limit daily living exacerbate School attendance modified avoid provocation Children returned completely adults. Because physiological risks diffuse swelling) childhood adolescence, recommended. extend adolescents. regardless athletic performance. apply even mandate cautious advice. Elite Versus Nonelite Athletes All participation, paradigm. resources expertise between elite nonelite individuals, organized having evaluation, Chronic Traumatic Encephalopathy (CTE) Clinicians mindful problems CTE represents tauopathy unknown incidence populations. relationship yet exposure sports.105–114 causation modern case cautiously. address fears parents/athletes media pressure possibility CTE. INJURY PREVENTION Protective Equipment—Mouthguards Helmets good prevent mouthguards definite preventing dental oro-facial Biomechanical reduction forces headgear helmets, translated show incidence. For skiing snowboarding helmets protection against facial participants alpine sports.115–118 cycling, motor, equestrian falling hard surfaces prevention issue sports.118–130 Rule Change Consideration reduce clear-cut mechanism implicated sport. example football (soccer) upper limb heading contests accounted 50% concussions.131 earlier, needed effective compromising athlete's welfare, enforcement critical settings referees regard. Risk Compensation compensation.132 behavioral adoption dangerous techniques, paradoxical increase rates. degree detail review BJSM supplement. concern rates higher athletes.133–135 Aggression Violence competitive/aggressive fun watch discouraged.