Special Feature

C 4 inH

AuPa y, MRoLa utcher, MD,M vis, MBBS,Ric ,Gr Crea, PhD,An MBBS, PhD,LaCh

PR

Th(VCoInt

ouprocoThinvlev

thement and return to play (RTP) decisions remain in the realm of clinical judgment on anindCoAsanauan

1.

2.3.4.

in British Journalrican Journal ofJournal of SportsTraining, Journalournal of Clinical), Journal of Sci-rt, Physician andery, Scandinavianine in Sport, Southurnal, and Cana-ournal.

und on page 269.

PM up193 013

Prin .012255ividualized basis. Readers are encouraged to copy and distribute freely the Zurichnsensus document, the Concussion Recognition Tool (CRT), the Sports Concussionsessment Tool version 3 (SCAT3), and/or the Child SCAT3 card, and neither is subject toy restriction, provided it is not altered in any way or converted to a digital format. Thethors request that the document and/or the accompanying tools be distributed in their fulld complete format.This consensus paper is broken into a number of sections

A summary of concussion and its management, with updates from the previousmeetings.Background information about the consensus meeting process.A summary of the specific consensus questions discussed at this meeting.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).

This article will also appearof Sports Medicine, AmeSports Medicine, ClinicalMedicine, Journal of Athleticof Clincal Neuroscience, JSports Medicine (Japaneseence and Medicine in SpoSportsmedicine, NeurosurgJournal of Science & MedicAfrican Sports Medicine Jodian Medical Association J

Author affiliations can be fo

&R 2013 Concussion in Sport Gro4-1482/13/$36.00 Vol. 5, 255-279, April 2

ted in U.S.A. http://dx.doi.org/10.1016/j.pmrj.2013.02onsensus Statement on Concussion in Sportth International Conference on Concussioneld in Zurich, November 2012

thors:ul McCrory, MBBS, PhD, Willem H. Meeuwisse, MD, PhD, Mark Aubrbert C. Cantu, MD, Jir Dvork, MD, Ruben J. Echemendia, PhD,rs Engebretsen, MD, PhD, Karen M. Johnston, MD, PhD, Jeffrey S. Kartin Raftery, MBBS, Allen Sills, MD, Brian W. Benson, MD, PhD, Gavin A. Dahard Ellenbogen, MD, Kevin M. Guskiewicz, PhD, Stanley A. Herring, MDant L. Iverson, PhD, Barry D. Jordan, MD, James Kissick, MD, Michael Mcdrew S. McIntosh, PhD, David L. Maddocks, LLB, PhD, Michael Makdissi,ura Purcell, MD, Margot Putukian, MD, Kathryn Schneider, PhD,arles H. Tator, MD, PhD, Michael Turner, MD

EAMBLE

is paper is a revision and update of the recommendations developed following the 1stienna 2001), 2nd (Prague 2004), and 3rd (Zurich 2008) International Consensusnference on Concussion in Sport, and is based on the deliberations at the 4thernational Conference on Concussion in Sport held in Zurich, November 2012 [1-3].The new 2012 Zurich Consensus statement is designed to build on the principlestlined in the previous documents and to develop further conceptual understanding of thisblem by using a formal consensus-based approach. A detailed description of the

nsensus process is outlined at the end of this document under the background section.is document is developed for use by physicians and health care professionals who areolved in the care of injured athletes, whether at the recreational, elite, or professionalel.While agreement exists pertaining to principal messages conveyed within this document,authors acknowledge that the science of concussion is evolving, and therefore manage-TheSport

D,

SEM

ThmaPraco

De

PaitsheSpcocoterthecauthaCobecomcoco

Re

Th(7-lon

Sy

ThsesphtursioinjamouAp

mo

(a)

(b)(c)(d)(e)

If asiostr

OC

W

(a)

(b)

(c)

(d)

256 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORTCTION 1: SPORT CONCUSSION AND ITSANAGEMENT

e Zurich 2012 document examines sport concussion andnagement issues raised in the previous Vienna 2001,gue 2004, and Zurich 2008 documents, and applies the

nsensus questions from Section 3 to these areas [1-3].

finition of Concussion

nel discussion regarding the definition of concussion andseparation from mild traumatic brain injury (mTBI) was

ld. There was acknowledgement by the Concussion inort Group (CISG) that, although the terms mTBI andncussion are often used interchangeably in the sportingntext and particularly in the U.S. literature, others use them to refer to different injury constructs. Concussion is

historical term representing low-velocity injuries thatse brain shaking, resulting in clinical symptoms andt are not necessarily related to a pathologic injury.ncussion is a subset of TBI and the term concussion willused in this document. It was also noted that the termmotio cerebri is often used in European and other

untries. Minor revisions were made to the definition ofncussion, and it is defined as follows:

Concussion is a brain injury and is defined as acomplex pathophysiological process affecting thebrain, induced by biomechanical forces. Severalcommon features that incorporate clinical, patho-logic, and biomechanical injury constructs that maybe utilized in defining the nature of a concussivehead injury include

1. Concussion may be caused either by a direct blowto the head, face, neck, or elsewhere on the bodywith an impulsive force transmitted to the head.

2. Concussion typically results in the rapid onset ofshort-lived impairment of neurologic function thatresolves spontaneously. However, in some cases,symptoms and signs may evolve over a number ofminutes to hours.

3. Concussion may result in neuropathologic changes,but the acute clinical symptoms largely reflect afunctional disturbance rather than a structural in-jury, and, as such, no abnormality is seen on stan-dard structural neuroimaging studies.

4. Concussion results in a graded set of clinical symp-toms that may or may not involve loss of conscious-ness. Resolution of the clinical and cognitive symp-toms typically follows a sequential course. However, it

is important to note that in some cases symptoms maybe prolonged.

(e)covery of Concussion

e majority (80%-90%) of concussions resolve in a short10 day) period, although the recovery time frame may beger in children and adolescents. [2].

mptoms and Signs of Acute Concussion

e diagnosis of acute concussion usually involves the as-sment of a range of domains, including clinical symptoms,ysical signs, cognitive impairment, neurobehavioral fea-es, and sleep disturbance. Furthermore, a detailed concus-n history is an important part of the evaluation, both in theured athlete and when conducting a preparticipation ex-ination. The detailed clinical assessment of concussion istlined in the SCAT3 and Child SCAT3 forms, which is anpendix to this document.The suspected diagnosis of concussion can include one orre of the following clinical domains:

Symptomssomatic (eg, headache), cognitive (eg,feeling like in a fog), and/or emotional symptoms (eg,lability)Physical signs (eg, loss of consciousness, amnesia)Behavioral changes (eg, irritability)Cognitive impairment (eg, slowed reaction times)Sleep disturbance (eg, insomnia)

ny one or more of these components is present, a concus-n should be suspected and the appropriate managementategy instituted.

n-field or Sideline Evaluation of Acuteoncussion

hen a player shows ANY features of a concussion:

The player should be evaluated by a physician or otherlicensed health care provider onsite by using standardemergency management principles, and particular at-tention should be given to excluding a cervical spineinjury.The appropriate disposition of the player must be deter-mined by the treating health care provider in a timelymanner. If no health care provider is available, theplayer should be safely removed from practice or playand urgent referral to a physician arranged.Once the first aid issues are addressed, then an assess-ment of the concussive injury should be made by usingthe SCAT3 or other sideline assessment tools.The player should not be left alone following the injury,and serial monitoring for deterioration is essential overthe initial few hours following injury.

A player with diagnosed concussion should not be al-lowed to return to play on the day of injury.

shbospofffloteasisjud

cochfuntesqusioquunmeabsiocoidesenepon

tomfolbe

Evby

Angenfolprofea

(a)

(b)

(c)

Inass

C

A rinstrinjBratosufraprode

vatrecassadnaphcocoan

tecbaidemapeobtiotiopaco

momaunanstrsupromutorsuatcerS-1[MwhThthe

evo

257PM&R Vol. 5, Iss. 4, 2013Sufficient time for assessment and adequate facilitiesould be provided for the appropriate medical assessment,th on and off the field, for all injured athletes. In someorts, this may require rule change to allow an appropriate-field medical assessment to occur without affecting thew of the game or unduly penalizing the injured playersm. The final determination regarding concussion diagno-and/or fitness to play is a medical decision based on clinicalgment.Sideline evaluation of cognitive function is an essential

mponent in the assessment of this injury. Brief neuropsy-ological test batteries that assess attention and memoryction have been shown to be practical and effective. Such

ts include the SCAT3, which incorporates the Maddocksestions [4,5], and the Standardized Assessment of Concus-n (SAC) [6-8]. It is worth noting that standard orientationestions (eg, time, place, person) have been shown to bereliable in the sporting situation when compared withmory assessment [5,9]. It is recognized, however, that

breviated testing paradigms are designed for rapid concus-n screening on the sidelines and are not meant to replacemprehensive neuropsychological testing, which shouldally be performed by trained neuropsychologists who aresitive to subtle deficits that may exist beyond the acute

isode; nor should they be used as a stand-alone tool for thegoing management of sports concussions.It should also be recognized that the appearance of symp-s or cognitive deficit might be delayed several hours

lowing a concussive episode and that concussion shouldseen as an evolving injury in the acute stage.

aluation in Emergency Room or OfficeMedical Personnel

athlete with concussion may be evaluated in the emer-cy room or doctors office as a point of first contact

lowing injury or may have been referred from another carevider. In addition to the points outlined above, the keytures of this examination should encompass:

A medical assessment including a comprehensive his-tory and detailed neurological examination, including athorough assessment of mental status, cognitive func-tioning, gait, and balance.A determination of the clinical status of the patient,including whether there has been improvement or de-terioration since the time of injury. This may involveseeking additional information from parents, coaches,teammates, and eyewitness to the injury.A determination of the need for emergent neuroimagingin order to exclude a more severe brain injury involvinga structural abnormality.large part, these points above are included in the SCAT3essment.

tioduoncussion Investigations

ange of additional investigations may be utilized to assistthe diagnosis and/or exclusion of injury. Conventionaluctural neuroimaging is typically normal in concussiveury. Given that caveat, the following suggestions are made:in CT (or where available MR brain scan) contributes little

concussion evaluation but should be employed wheneverspicion of an intracerebral or structural lesion (eg, skullcture) exists. Examples of such situations may includelonged disturbance of conscious state, focal neurologic

ficit, or worsening symptoms.Other imaging modalities such as fMRI demonstrate acti-ion patterns that correlate with symptom severity andovery in concussion [10-14]. While not part of routineessment at the present time, they nevertheless provideditional insight to pathophysiological mechanisms. Alter-tive imaging technologies (eg, positron emission tomogra-y, diffusion tensor imaging, magnetic resonance spectros-py, functional connectivity), while demonstrating somempelling findings, are still at early stages of developmentd cannot be recommended other than in a research setting.Published studies, using both sophisticated force platehnology as well as those using less sophisticated clinicallance tests (eg, Balance Error Scoring System [BESS]), haventified acute postural stability deficits lasting approxi-tely 72 hours following sport-related concussion. It ap-ars that postural stability testing provides a useful tool forjectively assessing the motor domain of neurologic func-ning and should be considered a reliable and valid addi-n to the assessment of athletes suffering from concussion,rticularly where symptoms or signs indicate a balancemponent [15-21].The significance of apolipoprotein (Apo) E4, ApoE pro-tor gene, tau polymerase, and other genetic markers in thenagement of sports concussion risk or injury outcome isclear at this time [22,23]. Evidence from human andimal studies in more severe traumatic brain injury demon-ate induction of a variety of genetic and cytokine factors,ch as insulin-like growth factor-1 (IGF-1), IGF bindingtein-2, fibroblast growth factor, Cu-Zn superoxide dis-tase, superoxide dismutase-1 (SOD-1), nerve growth fac-, glial fibrillary acidic protein (GFAP), and S-100. Howch factors are affected in sporting concussion is not knownthis stage [24-31]. In addition, biochemical serum andebral spinal fluid biomarkers of brain injury (including00, neuron specific enolase [NSE], myelin basic proteinBP], GFAP, tau, etc) have been proposed as means byich cellular damage may be detected if present [32-38].ere is currently insufficient evidence, however, to justifyroutine use of these biomarkers clinically.

Different electrophysiological recording techniques (eg,ked response potential [ERP], cortical magnetic stimula-n, and electroencephalography) have demonstrated repro-cible abnormalities in the postconcussive state; however,

nocorem

Ne

Thcuute51ovbepretioshofmunoshproen

netivnotio

whpepsvirtomuInmeap

typatitiopaintode[56

nometheadthetherou

C

ThcograRTrespeinjevaamdethecocan

befor

spexste

G

RTces

tincuthathrtomcuthelevof

Sa

Itcuthatojurlik

ThC

Pe10sp

258 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORTt all studies reliably differentiated concussed athletes fromntrols [39-45]. The clinical significance of these changes

ains to be established.

uropsychological Assessment

e application of neuropsychological (NP) testing in con-ssion has been shown to be of clinical value and contrib-s significant information in concussion evaluation [46-]. Although in most cases cognitive recovery largelyerlaps with the time course of symptom recovery, it hasen demonstrated that cognitive recovery may occasionallycede or more commonly follow clinical symptom resolu-

n, suggesting that the assessment of cognitive functionould be an important component in the overall assessmentconcussion and, in particular, any RTP protocol [52,53]. Itst be emphasized, however, that NP assessment should

t be the sole basis of management decisions. Rather, itould be seen as an aid to the clinical decision-makingcess in conjunction with a range of assessments of differ-

t clinical domains and investigational results.It is recommended that all athletes should have a clinicalurologic assessment (including assessment of their cogni-e function) as part of their overall management. This willrmally be done by the treating physician, often in conjunc-n with computerized NP screening tools.Formal NP testing is not required for all athletes, however,en this is considered necessary, then it should ideally be

rformed by a trained neuropsychologist. Although neuro-ychologists are in the best position to interpret NP tests bytue of their background and training, the ultimate returnplay decision should remain a medical one in which altidisciplinary approach, when possible, has been taken.the absence of NP and other (eg, formal balance assess-nt) testing, a more conservative RTP approach may bepropriate.NP testing may be used to assist RTP decisions and isically performed when an athlete is clinically asymptom-

c; however, NP assessment may add important informa-n in the early stages following injury [54,55]. There may berticular situations where testing is performed early to assistdetermining aspects of management, for example, returnschool for a pediatric athlete. This will normally be besttermined in consultation with a trained neuropsychologist,57].Baseline NP testing was considered by the panel and wast felt to be required as a mandatory aspect of every assess-nt, however, may be helpful or add useful information tooverall interpretation of these tests. It also provides an

ditional educative opportunity for the physician to discusssignificance of this injury with the athlete. At present,re is insufficient evidence to recommend the widespreadtine use of baseline NP testing.

pareconcussion Management

e cornerstone of concussion management is physical andgnitive rest until the acute symptoms resolve and then aded program of exertion before medical clearance andP. The current published evidence evaluating the effect oft following a sport-related concussion is sparse. An initialriod of rest in the acute symptomatic period followingury (24-48 hours) may be of benefit. Further research toluate the long-term outcome of rest, and the optimalount and type of rest, is needed. In the absence of evi-nce-based recommendations, a sensible approach involves

gradual return to school and social activities (beforentact sports) in a manner that does not result in a signifi-t exacerbation of symptoms.Low-level exercise for those who are slow to recover mayof benefit, although the optimal timing following injuryinitiation of this treatment is currently unknown.As described above, the majority of injuries will recover

ontaneously over several days. In these situations, it ispected that an athlete will proceed progressively through apwise RTP strategy [58].

raduated Return to Play Protocol

P protocol following a concussion follows a stepwise pro-s, as outlined in Table 1.With this stepwise progression, the athlete should con-ue to proceed to the next level if asymptomatic at therrent level. Generally, each step should take 24 hours sot an athlete would take approximately 1 week to proceedough the full rehabilitation protocol once they are asymp-atic at rest and with provocative exercise. If any postcon-

ssion symptoms occur while in the stepwise program, thenpatient should drop back to the previous asymptomatic

el and try to progress again after a further 24-hour periodrest has passed.

me-day RTP

was unanimously agreed that no RTP on the day of con-ssive injury should occur. There are data demonstratingt, at the collegiate and high school level, athletes allowedRTP on the same day may demonstrate NP deficits postin-y that may not be evident on the sidelines and are moreely to have delayed onset of symptoms [59-65].

e Difficult or Persistently Symptomaticoncussion Patient

rsistent symptoms (10 days) are generally reported in%-15% of concussions. In general, symptoms are notecific to concussion, and it is important to consider other

thologies. Cases of concussion in sport where clinicalovery falls outside the expected window (ie, 10 days)

shcar

PsHe

Psythi[66cuantra

Th

Phinmasledruogofprocia

athbemapremeontre

ThEv

Inapthe

copreproedinjcifilencothebeshfaccliofcuQusymgreclieqrec

the

Ta

Eachon

1. nd co2. onary

ximumraining

3. runninctiviti

4. ex traill andtance

5. e par

6.

259PM&R Vol. 5, Iss. 4, 2013ould be managed in a multidisciplinary manner by healthe providers with experience in sports-related concussion.

ychological Management and Mentalalth Issues

chological approaches may have potential application ins injury, particularly with the modifiers listed below,67]. Physicians are also encouraged to evaluate the con-

ssed athlete for affective symptoms, such as depression andxiety, because these symptoms are common in all forms ofumatic brain injury [58].

e Role of Pharmacologic Therapy

armacologic therapy in sports concussion may be applied2 distinct situations. The first of these situations is thenagement of specific and/or prolonged symptoms (eg,ep disturbance, anxiety). The second situation is whereg therapy is used to modify the underlying pathophysiol-

y of the condition with the aim of shortening the durationthe concussion symptoms [68]. In broad terms, this ap-ach to management should be only considered by clini-

ns experienced in concussion management.An important consideration in RTP is that concussedletes should not only be symptom free but also should nottaking any pharmacologic agents or medications that maysk or modify the symptoms of concussion. Where antide-ssant therapy may be commenced during the manage-nt of a concussion, the decision to return to play while stillsuch medication must be considered carefully by the

ating clinician.

e Role of Preparticipation Concussionaluation

recognizing the importance of a concussion history and

ble 1. Graduated return to play protocol

Rehabilitation StageFunctional Exercise at

Rehabilitati

No activity Symptom limited physical aLight aerobic exercise Walking, swimming, or stati

keeping intensity 70% maheart rate. No resistance t

Sport-specific exercise Skating drills in ice hockey,soccer. No head impact a

Non-contact training drills Progression to more compleg, passing drills in footbaMay start progressive resis

Full contact practice Following medical clearancnormal training activities.

Return to play Normal game play.preciating the fact that many athletes will not recognize allconcussions they may have suffered in the past, a detailed

Femoncussion history is of value [69-72]. Such a history may-identify athletes who fit into a high-risk category andvides an opportunity for the health care provider to

ucate the athlete in regard to the significance of concussiveury. A structured concussion history should include spe-c questions as to previous symptoms of a concussion andgth of recovery, not just the perceived number of past

ncussions. It is also worth noting that dependence uponrecall of concussive injuries by teammates or coaches has

en demonstrated to be unreliable [69]. The clinical historyould also include information about all previous head,e, or cervical spine injuries because these may also havenical relevance. It is worth emphasizing that, in the settingmaxillofacial and cervical spine injuries, coexistent con-ssive injuries may be missed unless specifically assessed.estions pertaining to disproportionate impact versusptom severity matching may alert the clinician to a pro-

ssively increasing vulnerability to injury. As part of thenical history, it is advised that details regarding protectiveuipment employed at time of injury be sought, both forent and remote injuries.There is an additional and often unrecognized benefit ofpreparticipation physical examination insofar as the eval-

tion allows for an educative opportunity with the playerncerned as well as consideration of modification of playinghavior if required.

odifying Factors in Concussionanagement

range of modifying factors may influence the investiga-n and management of concussion and, in some cases, maydict the potential for prolonged or persistent symptoms.wever, in some cases, the evidence for their efficacy isited. These modifiers would be important to consider in a

tailed concussion history and are outlined in Table 2.

Stage ofObjective of Each Stage

gnitive rest. Recoverycyclingpermitted

.

Increase heart rate

g drills ines.

Add movement

ning drills,ice hockey.training.

Exercise, coordination, and cognitiveload

ticipate in Restore confidence and assessfunctional skills by coaching staffuacobe

MM

AtiopreHolimdemale Gender. The role of female gender as a possibledifier in the management of concussion was discussed at

lenthaenit wan

Ththebraofdeit hCoutemo

ThThan[64butomamret

po[83

Mimvudrareqme

Dehabraagifololoofmatreco

Sp

Thanapyeadifsymtioathhepaapassyea

adeninpelatoccoormoneinne

actmaco

Ta

Sym

Sig

SeTem

Thr

Ag

Co

Me

BeSp

260 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORTgth by the panel. There was not unanimous agreementt the current published research evidence is conclusive

ough for this to be included as a modifying factor, althoughas accepted that gender may be a risk factor for injury

d/or influence injury severity [73-75].

e Significance of Loss of Consciousness (LOC). Inoverall management of moderate-to-severe traumatic

in injury, duration of LOC is an acknowledged predictoroutcome [76]. While published findings in concussionscribe LOC associated with specific early cognitive deficits,as not been noted as a measure of injury severity [77,78].nsensus discussion determined that prolonged (1 min-duration) LOC would be considered as a factor that maydify management.

e Significance of Amnesia and Other Symptoms.ere is renewed interest in the role of posttraumatic amnesiad its role as a surrogate measure of injury severity,79,80]. Published evidence suggests that the nature,

rden, and duration of the clinical postconcussive symp-s may be more important than the presence or duration of

ble 2. Concussion modifiers

Factors Modifier

ptoms NumberDuration ( 10 d)Severity

ns Prolonged loss ofconsciousness (1 min),amnesia

quelae Concussive convulsionsporal Frequencyrepeated

concussions over timeTiminginjuries closetogether in timeRecencyrecentconcussion or TBI

eshold Repeated concussionsoccurring with progressivelyless impact force or slowerrecovery after eachsuccessive concussion.

e Child and adolescent (18 yold)

- and pre-morbidities Migraine, depression or othermental health disorders,attention deficithyperactivity disorder,learning disabilities, sleepdisorders

dication Psychoactive drugs,anticoagulants

havior Dangerous style of playort High-risk activity, contact

and collision sport, highsporting levelnesia alone [77,81,82]. Further, it must be noted thatrograde amnesia varies with the time of measurement

eredastinjury and hence is poorly reflective of injury severity,84].

otor and Convulsive Phenomena. A variety ofmediate motor phenomena (eg, tonic posturing) or con-lsive movements may accompany a concussion. Althoughmatic, these clinical features are generally benign anduire no specific management beyond the standard treat-nt of the underlying concussive injury [85,86].

pression. Mental health issues (such as depression)ve been reported as a consequence of all levels of traumaticin injury, including sports-related concussion. Neuroim-ng studies with use of fMRI suggest that a depressed moodlowing concussion may reflect an underlying pathophysi-gical abnormality consistent with a limbic-frontal modeldepression [34,87-97]. While such mental health issuesy be multifactorial in nature, it is recommended that theating physician consider these issues in the management ofncussed patients.

ecial Populations

e Child and Adolescent Athlete. The evaluationd management recommendations contained herein can beplied to children and adolescents down to the age of 13rs. Below that age, children report concussion symptomsferent from adults and would require age-appropriate

ptom checklists as a component of assessment. An addi-nal consideration in assessing the child or adolescentlete with a concussion is that the clinical evaluation by the

alth care professional may need to include both patient andrent input, and possibly teacher and school input whenpropriate [98-104]. A child SCAT3 has been developed toess concussion (see Appendix) for subjects aged 5-12rs.The decision to use NP testing is broadly the same as theult assessment paradigm, although there are some differ-ces. Timing of testing may differ in order to assist planningschool and home management. If cognitive testing is

rformed, then it must be developmentally sensitive untile teen years due to the ongoing cognitive maturation thatcurs during this period, which, in turn, makes the utility ofmparison to either the persons own baseline performanceto population norms limited [20]. In this age group, it isre important to consider the use of trained pediatric

uropsychologists to interpret assessment data, particularlychildren with learning disorders and/or ADHD who mayed more sophisticated assessment strategies [56,57,98].It was agreed by the panel that no return to sport orivity should occur before the child/adolescent athlete hasnaged to return to school successfully. In addition, the

ncept of cognitive rest was highlighted with special ref-

nce to a childs need to limit exertion with activities ofily living that may exacerbate symptoms. School atten-

daprotoreq

londifchpramtheapsiolevevmo

Eli

AlmaThuamemathemeatiles

C

Clterevthywanoorintshimfro

In

ProThpromoorotioansh

snhehespmoothtopre

Ruthewhspseainconeassfarplamasetreg

Risussatresdaicainoft

Agtivanorgmasp

Kn

Beinjleathiandeniqedeodegrosp

261PM&R Vol. 5, Iss. 4, 2013nce and activities may also need to be modified to avoidvocation of symptoms. Children should not be returned

sport until clinically completely symptom free, which mayuire a longer time frame than for adults.Because of the different physiological responses andger recovery after concussion and specific risks (eg,fuse cerebral swelling) related to head impact duringildhood and adolescence, a more conservative RTP ap-oach is recommended. It is appropriate to extend theount of time of asymptomatic rest and/or the length ofgraded exertion in children and adolescents. It is not

propriate for a child or adolescent athlete with concus-n to RTP on the same day as the injury regardless of theel of athletic performance. Concussion modifiers apply

en more to this population than adults and may mandatere cautious RTP advice.

te Versus Nonelite Athletes

l athletes, regardless of level of participation, should benaged by using the same treatment and RTP paradigm.e available resources and expertise in concussion eval-tion are of more importance in determining manage-nt than a separation between elite and nonelite athletenagement. Although formal NP testing may be beyondresources of many sports or individuals, it is recom-

nded that, in all organized high-risk sports, consider-on be given to having this cognitive evaluation, regard-s of the age or level of performance.

hronic Traumatic Encephalopathy

inicians need to be mindful of the potential for long-m problems in the management of all athletes. How-er, it was agreed that CTE represents a distinct tauopa-

with an unknown incidence in athletic populations. Its further agreed that a cause and effect relationship hast yet been demonstrated between CTE and concussionsexposure to contact sports [105-114]. At present, theerpretation of causation in the modern CTE case studiesould proceed cautiously. It was also recognized that it isportant to address the fears of parents and/or athletesm media pressure related to the possibility of CTE.

jury Prevention

tective Equipment: Mouthguards and Helmets.ere is no good clinical evidence that currently availabletective equipment will prevent concussion, althoughuthguards have a definite role in preventing dental andfacial injury. Biomechanical studies have shown a reduc-

n in impact forces to the brain with the use of head gear

d helmets, but these findings have not been translated toow a reduction in concussion incidence. For skiing and

As(IOowboarding, there are a number of studies to suggest thatlmets provide protection against head and facial injury andnce should be recommended for participants in alpineorts [115-118]. In specific sports, such as cycling andtor and equestrian sports, protective helmets may preventer forms of head injury (eg, skull fracture) that are relatedfalling on hard surfaces and may be an important injuryvention issue for those sports [118-130].

le Change. Consideration of rule changes to reducehead injury incidence or severity may be appropriate

ere a clear-cut mechanism is implicated in a particularort. An example of this is in football (soccer) where re-rch studies demonstrated that upper limb to head contactheading contests accounted for approximately 50% of

ncussions [131]. As noted earlier, rule changes also may beeded in some sports to allow an effective off-field medicalessment to occur without compromising the athletes wel-e, affecting the flow of the game, or unduly penalizing theyers team. It is important to note that rule enforcementy be a critical aspect of modifying injury risk in thesetings and that referees play an important role in thisard.

k Compensation. An important consideration in thee of protective equipment is the concept of risk compen-ion [132]. This is where the use of protective equipmentults in behavioral change such as the adoption of morengerous playing techniques, which can result in a paradox-l increase in injury rates. This may be a particular concernchild and adolescent athletes where head injury rates areen higher than in adult athletes [133-135].

gression Versus Violence in Sport. The competi-e and/or aggressive nature of sport that makes it fun to playd watch should not be discouraged. However, sportinganizations should be encouraged to address violence thaty increase concussion risk [136,137]. Fair play and re-

ect should be supported as key elements of sport.

owledge Transfer

cause the ability to treat or reduce the effects of concussiveury after the event is minimal, education of athletes, col-gues, and the general public is a mainstay of progress ins field. Athletes, referees, administrators, parents, coaches,d health care providers must be educated regarding thetection of concussion, its clinical features, assessment tech-ues, and principles of safe RTP. Methods to improve

ucation, including Web-based resources, educational vid-s, and international outreach programs, are important inlivering the message. In addition, concussion workingups, plus the support and endorsement of enlightened

ort groups such as Fdration Internationale de Football

sociation (FIFA), International Olympic CommissionC), International Rugby Board (IRB), and International

Icehaplabelarin[58

SETO

InCoingthemauponwiPraaimthecoweinvmicoeqco

waantheInscanhtmsen

1.

2.

3.

4.

5.

6.

adreceradecowesta

waanspwePoeacen

M

Thedmethainintasnacarfacintup

SEQ

Norevcintop

haco

262 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORTHockey Federation (IIHF) who initiated this endeavorve enormous value and must be pursued vigorously. Fairy and respect for opponents are ethical values that shouldencouraged in all sports and sporting associations. Simi-ly, coaches, parents, and managers play an important partensuring these values are implemented on the field of play,138-150].

CTION 2: STATEMENT ON BACKGROUNDTHE CONSENSUS PROCESS

November 2001, the 1st International Conference onncussion in Sport was held in Vienna, Austria. This meet-was organized by the IIHF in partnership with FIFA andMedical Commission of the IOC. As part of the resulting

ndate for the future, the need for leadership and futuredates were identified. The 2nd International ConferenceConcussion in Sport was organized by the same group,

th the additional involvement of the IRB and was held ingue, Czech Republic, in November 2004. The originals of the symposia were to provide recommendations forimprovement of safety and health of athletes who suffer

ncussive injuries in ice hockey, rugby, football (soccer) asll as other sports. To this end, a range of experts wereited to both meetings to address specific issues of epide-ology, basic and clinical science, injury grading systems,gnitive assessment, new research methods, protectiveuipment, management, prevention, and long-term out-me [1,2].The 3rd International Conference on Concussion in Sports held in Zurich, Switzerland, on October 29-30, 2008,d was designed as a formal consensus meeting following

organizational guidelines set forth by the U.S. Nationaltitutes of Health. (Details of the consensus methodology

be obtained at http://consensus.nih.gov/ABOUTCDP..) The basic principles governing the conduct of a con-

sus development conference are summarized below:

A broad-based nongovernment, nonadvocacy panel wasassembled to give balanced, objective, and knowledgeableattention to the topic. Panel members excluded anyonewith scientific or commercial conflicts of interest andincluded researchers in clinical medicine, sports medi-cine, neuroscience, neuroimaging, athletic training, andsports science.These experts presented data in a public session, followedby inquiry and discussion. The panel then met in anexecutive session to prepare the consensus statement.A number of specific questions were prepared and posedin advance to define the scope and guide the direction ofthe conference. The principal task of the panel was to

elucidate responses to these questions. These questionsare outlined below. injA systematic literature review was prepared and circu-lated in advance for use by the panel in addressing theconference questions.The consensus statement is intended to serve as the sci-entific record of the conference.The consensus statement will be widely disseminated toachieve maximum impact on both current health carepractice and future medical research.

The panel chairperson (W.M.) did not identify with anyvocacy position. The chairperson was responsible for di-ting the consensus session and guiding the panels delib-tions. Panelists were drawn from clinical practice, aca-mics, and research in the field of sports-relatedncussion. They do not represent organizations per se butre selected for their expertise, experience, and under-nding of this field.The 4th International Conference on Concussion in Sports held in Zurich, Switzerland, on November 1-3, 2012,d followed the same outline as for the 3rd meeting. Alleakers, consensus panel members, and abstract authorsre required to sign an ICMJE Form for Disclosure oftential Conflicts of Interest. Detailed information related toh authors affiliations and conflicts of interests are at the

d of this article.

edical-Legal Considerations

is consensus document reflects the current state of knowl-ge and will need to be modified according to the develop-nt of new knowledge. It provides an overview of issuest may be of importance to health care providers involvedthe management of sports-related concussion. It is notended as a standard of care and should not be interpretedsuch. This document is only a guide and is of a generalture, consistent with the reasonable practice of a healthe professional. Individual treatment will depend on thets and circumstances specific to each individual case. It isended that this document will be formally reviewed anddated before December 1, 2016.

CTION 3: ZURICH 2012 CONSENSUSUESTIONS

te that each question is the subject of a separate systematiciew that is published in the British Journal of Sports Medi-e (2013;47:5). As such, all citations and details of eachic will be covered in those reviews.1. When you assess an athlete acutely and they do notve concussion, what is it? Is a cognitive injury the keymponent of concussion in making a diagnosis?

The consensus panel agreed that concussion is an evolvingury in the acute phase with rapidly changing clinical signs

anicaamdiaspsigthacoevowhnefrotreIt wacuex

reldia

obvaferorcoousiotecnacalcoThfunintus

ath

athheassstrtivsersiorelnetimasstheogcraoft

aningpaimuscojud

emprathinins(SCblestu

anCoansymnitanrecingavpearbperesvisreathecomaagyoSC

tes

wicoustestheizathevasp

263PM&R Vol. 5, Iss. 4, 2013d symptoms, which may reflect the underlying physiolog-l injury in the brain. Concussion is considered to beong the most complex injuries in sports medicine tognose, assess, and manage. The majority of concussions in

ort occur without loss of consciousness or frank neurologicns. At present, there is no perfect diagnostic test or markert clinicians can rely on for an immediate diagnosis of

ncussion in the sporting environment. Because of thislving process, it is not possible to rule out concussionen an injury event occurs associated with a transient

urological symptom. All such cases should be removedm the playing field and assessed for concussion by theating physician or health care provider as discussed below.as recognized that a cognitive deficit is not necessary forte diagnosis as it either may not be present or detected on

amination.2. Are the existing tools/examinations sensitive andiable enough on the day of injury to make or exclude agnosis of concussion?Concussion is a clinical diagnosis based largely on theserved injury mechanism, signs, and symptoms. Thest majority of sport-related concussions (hereafter, re-red to as concussion) occur without loss of consciousnessfrank neurologic signs [151-154]. In milder forms of

ncussion, the athlete might be slightly confused, with-t clearly identifiable amnesia. In addition, most concus-ns cannot be identified or diagnosed by neuroimaginghniques (eg, computed tomography or magnetic reso-nce imaging). Several well-validated neuropsychologi-tests are appropriate for use in the assessment of acute

ncussion in the competitive sporting environment.ese tests provide important data on symptoms andctional impairments that clinicians can incorporate

o their diagnostic formulation but should not solely beed to diagnose concussion.3. What is the best practice for evaluating an adultlete with concussion on the field of play in 2012?Recognizing and evaluating concussion in the adultlete on the field is a challenging responsibility for the

alth care provider. Performing this task is often a rapidessment in the midst of competition with a time con-aint and the athlete eager to play. A standardized objec-e assessment of injury, which includes excluding moreious injury, is critical in determining disposition deci-ns for the athlete. The on-field evaluation of sport-ated concussion is often a challenge given the elusive-ss and variability of presentation, difficulty in making aely diagnosis, specificity and sensitivity of sidelineessment tools, and the reliance on symptoms. Despitese challenges, the sideline evaluation is based on rec-

nition of injury, assessment of symptoms, cognitive and

nial nerve function, and balance. Serial assessments areen necessary. Concussion is often an evolving injury,

thecod signs and symptoms may be delayed. Therefore, err-on the side of caution (keeping an athlete out of

rticipation when there is any suspicion for injury) isportant. A standardized assessment of concussion iseful in the assessment of the athlete with suspectedncussion but should not take the place of cliniciangment.4. How can the SCAT2 be improved?It was agreed that a variety of measures should beployed as part of the assessment of concussion to

ovide a more complete clinical profile for the concussedlete. Important clinical information can be ascertaineda streamlined manner through the use of a multimodaltrument such as the Sport Concussion Assessment ToolAT). A baseline assessment is advised wherever possi-. However, it is acknowledged that further validitydies need to be performed to answer this specific issue.A future SCAT test battery (ie, SCAT3) should includeinitial assessment of injury severity using the Glasgowma Scale (GCS), immediately followed by observingd documenting concussion signs. Once this is complete,

ptom endorsement and symptom severity, neurocog-ive function, and balance function should be assessed iny athlete suspected of sustaining a concussion. It isommended that these latter steps be conducted follow-a minimum 15-minute rest period on the sideline to

oid the influence of exertion or fatigue on the athletesrformance. While it is noted that this time frame is anitrary one, nevertheless, the expert panel agreed that a

riod of rest was important prior to assessment. Futureearch should consider the efficacy for inclusion ofion tests such as the King Devick Test and clinicalction time tests [155,156]. Recent studies suggest thatse may be useful additions to the sideline assessment of

ncussion. However, the need for additional equipmenty make them impractical for sideline use. It was further

reed that the SCAT3 would be suitable for adults anduths age 13 years old and over, while a new tool (ChildAT3) has been developed for younger children.5. Advances in neuropsychology: Are computerizedts sufficient for concussion diagnosis?Sport-related concussions are frequently associatedth one or more symptoms, impaired balance, and/orgnitive deficits. These problems can be measured bying symptom scales, balance testing, and neurocognitiveting. All 3 modalities can identify significant changes infirst few days following injury, generally with normal-

tion over 1-3 weeks. The presentation of symptoms andrate of recovery can be variable, which reinforces the

lue of assessing all 3 areas as part of a comprehensiveort concussion program.Neuropsychological assessment has been described byConcussion in Sport Group as a cornerstone ofncussion management. Neuropsychologists are uniqu-

elyplaedingprinsioizeassaccbepsevba

tecme

asssmrobtranelimnotanev

W

treAnfuranLobeforMuclifunhigphanrel

ap(>

inspdrsiotenne

inginsadstrrecshhecotheasscalmeeraa l

evsp

symproBriamcoshmicodaciecowifolmacoretresshsp

giepo

usAmcoatiredboantioimin

264 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORTqualified to interpret neuropsychological tests and cany an important role within the context of a multifacet-

-multimodal and multidisciplinary approach to manag-sport-related concussion. Concussion management

ograms that use neuropsychological assessment to assistclinical decision making have been instituted in profes-nal sports, colleges, and high schools. Brief computer-d cognitive evaluation tools are the mainstay of theseessments worldwide given the logistical limitation inessing trained neuropsychologists; however, it shouldnoted that these are not substitutes for formal neuro-

ychological assessment. At present, there is insufficientidence to recommend the widespread routine use ofseline neuropsychological testing.7. What evidence exists for new strategies and/orhnologies in the diagnosis of concussion and assess-nt of recovery?A number of novel technological platforms exist toess concussion, including (but not limited to) iPhone/art phone apps, quantitative electroencephalography,oticssensory motor assessment, telemedicine, eye-

cking technology, functional imaging and/or advanceduroimaging, and head impact sensors. At this stage, onlyited evidence exists for their role in this setting, and

ne have been validated as diagnostic. It will be impor-t to reconsider the role of these technologies once

idence is developed.8. Advances in the management of sport concussion:hat is evidence for concussion therapies?The current evidence evaluating the effect of rest andatment following a sport-related concussion is sparse.

initial period of rest may be of benefit. However,ther research to evaluate the long-term outcome of rest,d the optimal amount and type of rest, is needed.w-level exercise for those who are slow to recover mayof benefit, although the optimal timing following injury

initiation of this treatment is currently unknown.ltimodal physiotherapy treatment for individuals with

nical evidence of cervical spine and/or vestibular dys-ction may be of benefit. There is a strong need forh-level studies evaluating the effects of a resting period,armacologic interventions, rehabilitative techniques,d exercise for individuals who have sustained a sport-ated concussion.9. The difficult concussion patient: What is the bestproach to investigation and management of persistent10 days) postconcussive symptoms?Persistent symptoms (10 days) are generally reported10%-15% of concussions. This may be higher in certainorts (eg, elite ice hockey) and populations (eg, chil-en). In general, symptoms are not specific to concus-n, and it is important to consider and manage coexis-

t pathologies. Investigations may include formal

uropsychological testing and conventional neuroimag-siobeto exclude structural pathology. Currently, there isufficient evidence to recommend routine clinical use ofvanced neuroimaging techniques or other investigativeategies. Cases of concussion in sport where clinicalovery falls outside the expected window (ie, 10 days)

ould be managed in a multidisciplinary manner byalth care providers with experience in sports-relatedncussion. Important components of management after

initial period of physical and cognitive rest includeociated therapies, such as cognitive, vestibular, physi-, and psychological therapy; consideration of assess-nt of other causes of prolonged symptoms; and consid-tion of commencement of a graded exercise program at

evel that does not exacerbate symptoms.10. Revisiting concussion modifiers: How should thealuation and management of acute concussion differ inecific groups?The literature demonstrates that number and severity ofptoms and previous concussions are associated withlonged recovery and/or increased risk of complications.ef loss of consciousness (LOC), duration of posttraumaticnesia, and/or impact seizures do not reliably predict out-

me following concussion, although a cautious approachould be taken in an athlete with prolonged LOC (ie, 1nute). Children generally take longer to recover fromncussions, and assessment batteries have yet to be vali-ted in the younger age group. Currently, there are insuffi-nt data on the influence of genetics and gender on out-me following concussion. Several modifiers are associatedth prolonged recovery or increased risk of complicationslowing concussion and have important implications fornagement. Children with concussion should be managed

nservatively, with the emphasis on return to learn beforeurn to sport. In cases of concussion managed with limitedources (eg, nonelite players), a conservative approachould also be taken such that the athlete does not return toort until fully recovered11. What are the most effective risk-reduction strate-s in sport concussion? From protective equipment tolicy?No new valid evidence was provided to suggest that the

e of current standard headgear in rugby or mouthguards inerican football can significantly reduce players risk of

ncussion. No evidence was provided to suggest an associ-on between neck strength increases and concussion riskuction. There was evidence to suggest that eliminating

dy checking from Pee Wee ice hockey (ages 11-12 years),d fair-play rules in ice hockey were effective injury preven-n strategies. Helmets need to be able to protect frompacts resulting in a head change in velocity of up to 10 m/sprofessional American football, and up to 7 m/s in profes-

nal Australian football. It also appears that helmets mustcapable of reducing head resultant linear acceleration to

be15muweiesgeasuwilegrul

relco

wifuralothetivthepuristhaCTchdrcopusatcauadpr

knpo

sioausiofurtioissiomecanevaitadeferevacataw

RE1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

265PM&R Vol. 5, Iss. 4, 2013low 50 g and angular acceleration components to below00 rad/s2 to optimize their effectiveness. Given that altifactorial approach is needed for concussion prevention,ll-designed and sport-specific prospective analytical stud-of sufficient power are warranted for mouthguards, head-r and helmets, facial protection, and neck strength. Mea-

ring the effect of rule changes should also be addressedth future studies, not only assessing new rule changes orislation but also alteration or reinforcement to existinges.12. What is the evidence for chronic concussionated changes? Behavioral, pathologic, and clinical out-mes.It was agreed that CTE represents a distinct tauopathyth an unknown incidence in athletic populations. It wasther agreed that CTE was not related to concussionsne or simply exposure to contact sports. At present,re are no published epidemiologic, cohort, or prospec-e studies relating to modern CTE. Due to the nature ofcase reports and pathologic case series that have been

blished, it is not possible to determine the causality ork factors with any certainty. As such, the speculationt repeated concussion or subconcussive impacts causeE remains unproven. The extent to which age-relatedanges, psychiatric or mental health illness, alcohol orug use, or coexisting medical or dementing illnessesntribute to this process is largely unaccounted for in theblished literature. At present, the interpretation of cau-ion in the modern CTE case studies should proceedtiously. It was also recognized that it is important to

dress the fears of parents and/or athletes from mediaessure related to the possibility of CTE.13. From consensus to action: How do we optimizeowledge transfer, education, and ability to influencelicy?The value of knowledge transfer (KT) as part of concus-n education is increasingly becoming recognized. Targetdiences benefit from specific learning strategies. Concus-n tools exist, but their effectiveness and impact requirether evaluation. The media are valuable in drawing atten-n to concussion, but efforts need to ensure that the publicaware of the right information. Social media as a concus-n education tool are becoming more prominent. Imple-ntation of KT models is one approach that organizations

use to assess knowledge gaps; identify, develop, andluate education strategies; and use the outcomes to facil-

te decision making. Implementing KT strategies requires afined plan. Identifying the needs, learning styles, and pre-red learning strategies of target audiences, coupled withluation, should be a piece of the overall concussion edu-

ion puzzle to have an impact on enhancing knowledge andareness.FERENCES. Aubry M, Cantu R, Dvorak J, et al. Summary and agreement statement

of the 1st International Symposium on Concussion in Sport, Vienna2001. Clin J Sport Med 2002;12:6-11.

. McCrory P, Johnston K, Meeuwisse W, et al. Summary and agreementstatement of the 2nd International Conference on Concussion inSport, Prague 2004. Br J Sports Med 2005;39:196-204.

. McCrory P, Meeuwisse W, Johnston K, et al. Consensus Statement onConcussion in Sport: The Third International Conference on Concus-sion in Sport held in Zurich, November 2008. Phys Sportsmed 2009;37:141-159.

. Maddocks D, Dicker G. An objective measure of recovery fromconcussion in Australian rules footballers. Sport Health 1989;7(Suppl):6-7.

. Maddocks DL, Dicker GD, Saling MM. The assessment of orientationfollowing concussion in athletes. Clin J Sport Med 1995;5:32-35.

. McCrea M. Standardized mental status assessment of sports concus-sion. Clin J Sport Med 2001;11:176-181.

. McCrea M, Kelly J, Randolph C, et al. Standardised assessment ofconcussion (SAC): On site mental status evaluation of the athlete.J Head Trauma Rehab. 1998;13:27-36.

. McCrea M, Randolph C, Kelly J. The Standardized Assessment ofConcussion (SAC): Manual for Administration, Scoring and Interpre-tation. 2nd ed. Waukesha, WI: 2000, 22-45

. McCrea M, Kelly JP, Kluge J, Ackley B, Randolph C. Standardizedassessment of concussion in football players. Neurology 1997;48:586-588.

. Chen J, Johnston K, Collie A, McCrory P, Ptito A. A validation of thepost concussion symptom scale in the assessment of complex concus-sion using cognitive testing and functional MRI. J Neurol NeurosurgPsychiatry 2007;78:1231-1238.

. Chen J, Johnston K, Frey S, Petrides M, Worsley K, Ptito A. Functionalabnormalities in symptomatic concussed athletes: An fMRI study.Neuroimage 2004;22:68-82.

. Chen JK, Johnston KM, Collie A, McCrory P, Ptito A. (14) Associationbetween symptom severity, cogsport tests results, and functional MRIactivation in symptomatic concussed athletes. Clin J Sport Med 2004;14:379.

. Chen JK, Johnston KM, Collie A, McCrory P, Ptito A. behaviouraland functional imaging outcomes in symptomatic concussed ath-letes measured with cogsport and functional MRI. Br J Sport Med2004;38:659.

. Ptito A, Chen JK, Johnston KM. Contributions of functional magneticresonance imaging (fMRI) to sport concussion evaluation. NeuroRe-habilitation 2007;22:217-227.

. Guskiewicz K. Postural stability assessment following concussion.Clin J Sport Med 2001;11:182-190.

. Guskiewicz KM. Assessment of postural stability following sport-related concussion. Curr Sports Med Rep 2003;2:24-30.

. Guskiewicz KM, Ross SE, Marshall SW. Postural stability and neuro-psychological deficits after concussion in collegiate athletes. J AthlTrain 2001;36:263-273.

. Cavanaugh JT, Guskiewicz KM, Giuliani C, Marshall S, Mercer V,Stergiou N. Detecting altered postural control after cerebral concus-sion in athletes with normal postural stability. Br J Sports Med2005;39:805-811.

. Cavanaugh JT, Guskiewicz KM, Giuliani C, Marshall S, Mercer VS,Stergiou N. Recovery of postural control after cerebral concussion:New insights using approximate entropy. J Athl Train 2006;41:305-313.

. Cavanaugh JT, Guskiewicz KM, Stergiou N. A nonlinear dynamicapproach for evaluating postural control: New directions for the

management of sport-related cerebral concussion. Sports Med 2005;35:935-950.

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

266 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORT. Fox ZG, Mihalik JP, Blackburn JT, Battaglini CL, Guskiewicz KM.Return of postural control to baseline after anaerobic and aerobicexercise protocols. J Athl Train 2008;43:456-463.

. Kristman VL, Tator CH, Kreiger N, et al. Does the apolipoproteinepsilon 4 allele predispose varsity athletes to concussion? A prospec-tive cohort study. Clin J Sport Med 2008;18:322-328.

. Terrell TR, Bostick RM, Abramson R, et al. APOE, APOE promoter,and Tau genotypes and risk for concussion in college athletes. ClinJ Sport Med 2008;18:10-17.

. Vagnozzi R, Tavazzi B, Signoretti S, et al. Temporal window ofmetabolic brain vulnerability to concussions: Mitochondrial-re-lated impairmentPart I. Neurosurgery 2007;61:379-388; dis-cussion 88-89.

. Hang CH, Chen G, Shi JX, Zhang X, Li JS. Cortical expression ofnuclear factor kappaB after human brain contusion. Brain Res 2006;1109:14-21.

. Peng RY, Gao YB, Xiao XY, et al. Study on the expressions of basicfibroblast growth factor and nervous growth factor genes in rat cere-bral concussion [in Chinese, with English abstract]. Zhongguo WeiZhong Bing Ji Jiu Yi Xue 2003;15:213-216.

. Yunoki M, Kawauchi M, Ukita N, et al. Effects of lecithinized SOD onsequential change in SOD activity after cerebral contusion in rats. ActaNeurochir Suppl 1998;71:142-145.

. Hinkle DA, Baldwin SA, Scheff SW, Wise PM. GFAP and S100betaexpression in the cortex and hippocampus in response to mild corticalcontusion. J Neurotrauma 1997;14:729-738.

. Holmin S, Schalling M, Hojeberg B, Nordqvist AC, Skeftruna AK,Mathiesen T. Delayed cytokine expression in rat brain followingexperimental contusion. J Neurosurg 1997;86:493-504.

. Sandberg Nordqvist AC, von Holst H, Holmin S, Sara VR, BellanderBM, Schalling M. Increase of insulin-like growth factor (IGF)-1, IGFbinding protein-2 and -4 mRNAs following cerebral contusion. BrainRes Mol Brain Res 1996;38:285-293.

. Fukuhara T, Nishio S, Ono Y, Kawauchi M, Asari S, Ohmoto T.Induction of Cu,Zn-superoxide dismutase after cortical contusioninjury during hypothermia. Brain Res 1994;657:333-336.

. Begaz T, Kyriacou DN, Segal J, Bazarian JJ. Serum biochemical mark-ers for post-concussion syndrome in patients with mild traumaticbrain injury. J Neurotrauma 2006;23:1201-1210.

. de Boussard CN, Lundin A, Karlstedt D, Edman G, Bartfai A, Borg J.S100 and cognitive impairment after mild traumatic brain injury. JRehabil Med 2005;37:53-57.

. Lima DP, Simao Filho C, Abib Sde C, de Figueiredo LF. Quality of lifeand neuropsychological changes in mild head trauma. Late analysisand correlation with S100B protein and cranial CT scan performed athospital admission. Injury 2008;39:604-611.

. Ma M, Lindsell CJ, Rosenberry CM, Shaw GJ, Zemlan FP. Serumcleaved tau does not predict postconcussion syndrome after mildtraumatic brain injury. Am J Emerg Med 2008;26:763-768.

. Stalnacke BM, Tegner Y, Sojka P. Playing ice hockey and basketballincreases serum levels of S-100B in elite players: A pilot study. ClinJ Sport Med 2003;13:292-302.

. Stalnacke BM, Tegner Y, Sojka P. Playing soccer increases serumconcentrations of the biochemical markers of brain damage S-100Band neuron-specific enolase in elite players: A pilot study. Brain Inj2004;18:899-909.

. Townend W, Ingebrigtsen T. Head injury outcome prediction: A rolefor protein S-100B? Injury 2006;37:1098-1108.

. Boutin D, Lassonde M, Robert M, Vanassing P, Ellemberg D. Neuro-physiological assessment prior to and following sports-related con-cussion during childhood: A case study. Neurocase 2008;14:239-248.

. De Beaumont L, Brisson B, Lassonde M, Jolicoeur P. Long-term

electrophysiological changes in athletes with a history of multipleconcussions. Brain Inj 2007;21:631-644.. De Beaumont L, Lassonde M, Leclerc S, Theoret H. Long-term andcumulative effects of sports concussion on motor cortex inhibition.Neurosurgery 2007;61:329-336; discussion 36-37.

. Gaetz M, Weinberg H. Electrophysiological indices of persistent post-concussion symptoms. Brain Inj 2000;14:815-832.

. Gosselin N, Theriault M, Leclerc S, Montplaisir J, Lassonde M.Neurophysiological anomalies in symptomatic and asymptomaticconcussed athletes. Neurosurgery 2006;58:1151-1161; discussion1161.

. Lavoie ME, Dupuis F, Johnston KM, Leclerc S, Lassonde M. Visualp300 effects beyond symptoms in concussed college athletes. J ClinExp Neuropsychol 2004;26:55-73.

. Rousseff RT, Tzvetanov P, Atanassova PA, Volkov I, Hristova I. Cor-relation between cognitive P300 changes and the grade of closed headinjury. Electromyogr Clin Neurophysiol 2006;46:275-277.

. Collie A, Darby D, Maruff P. Computerised cognitive assessment ofathletes with sports related head injury. Br J Sports Med 2001;35:297-302.

. Collie A, Maruff P. Computerised neuropsychological testing. Br JSports Med 2003;37:2-3.

. Collie A, Maruff P, McStephen M, Darby DG. Psychometric issuesassociated with computerised neuropsychological assessment of con-cussed athletes. Br J Sports Med 2003;37:556-559.

. Collins MW, Grindel SH, Lovell MR, et al. Relationship betweenconcussion and neuropsychological performance in college footballplayers [see comments]. JAMA 1999;282:964-970.

. Lovell MR. The relevance of neuropsychologic testing for sports-related head injuries. Curr Sports Med Rep 2002;1:7-11.

. Lovell MR, Collins MW. Neuropsychological assessment of the collegefootball player. J Head Trauma Rehabil 1998;13:9-26.

. Bleiberg J, Cernich AN, Cameron K, et al. Duration of cognitiveimpairment after sports concussion. Neurosurgery 2004;54:1073-1078; discussion 8-80.

. Bleiberg J, Warden D. Duration of cognitive impairment after sportsconcussion. Neurosurgery 2005;56:E1166.

. Broglio SP, Macciocchi SN, Ferrara MS. Neurocognitive performanceof concussed athletes when symptom free. J Athl Train 2007;42:504-508.

. Broglio SP, Macciocchi SN, Ferrara MS. Sensitivity of the concus-sion assessment battery. Neurosurgery 2007;60:1050-1057; dis-cussion 7-8.

. Gioia G, Janusz J, Gilstein K, Iverson GL. Neuropsychological man-agement of consussion in children and adolescents: Effects of age andgender on ImPact. [abstract]. Br J Sp Med 2004;38:657.

. McCrory P, Collie A, Anderson V, Davis G. Can we manage sportrelated concussion in children the same as in adults? Br J Sports Med2004;38:516-519.

. Johnston K, Bloom G, Ramsay J, et al. Current Concepts in Concus-sion Rehabilitation. Curr Sports Med Rep 2004;3:316-323.

. Guskiewicz KM, McCrea M, Marshall SW, et al. Cumulative effectsassociated with recurrent concussion in collegiate football players.JAMA 2003;290:2549-2555.

. Lovell M, Collins M, Bradley J. Return to play following sports-relatedconcussion. Clin Sports Med 2004;23:421-441, ix.

. Collins M, Field M, Lovell M, GI, et al. Relationship between postcon-cussion headache and neuropsychological test performance in highschool athletes. Am J Sports Med 2003;31:168-173.

. Collins M, Grindel S, Lovell M, et al. Relationship between concussionand neuropsychological performance in college football players.JAMA 1999;282:964-970.

. Collins MW, Lovell MR, Iverson GL, Cantu RC, Maroon JC, Field M.

Cumulative effects of concussion in high school athletes. Neurosur-gery 2002;51:1175-1179; discussion 80-1.

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

10

10

10

10

10

10

10

10

10

10

267PM&R Vol. 5, Iss. 4, 2013. McCrea M, Guskiewicz KM, Marshall SW, et al. Acute effects andrecovery time following concussion in collegiate football players.JAMA 2003;290:2556-2563.

. McCrea M, Hammeke T, Olsen G, Leo P, Guskiewicz K. Unreportedconcussion in high school football players: Implications for preven-tion. Clin J Sport Med 2004;14:13-17.

. Bloom G, Horton A, McCrory P, Johnston K. Sport psychology andconcussion: New impacts to explore. Br J Sports Med 2004;38:519-521.

. Weiss MR, Gill DL. What goes around comes around: Re-emergingthemes in sport and exercise psychology. Res Q Exerc Sport 2005;76(Suppl):S71-S87.

. McCrory P. Should we treat concussion pharmacologically? The needfor evidence based pharmacological treatment for the concussed ath-lete. Br J Sports Med 2002;36:3-5.

. McCrory P. Preparticipation assessment for head injury. Clin J SportMed 2004;14:139-144.

. Johnston KM, Lassonde M, Ptito A. A contemporary neurosurgicalapproach to sport-related head injury: The McGill Concussion Proto-col. J Am Coll Surg 2001;192:515-524.

. Delaney J, Lacroix V, Leclerc S, Johnston K. Concussions duringthe 1997 Canadian Football League Season. Clin J Sport Med2000;10:9-14.

. Delaney J, Lacroix V, Leclerc S, Johnston K. Concussions amonguniversity football and soccer players. Clin J Sport Med 2002;12:331-338.

. Gessel LM, Fields SK, Collins CL, Dick RW, Comstock RD. Concus-sions among United States high school and collegiate athletes. J AthlTrain 2007;42:495-503.

. Dvorak J, Junge A, Fuller C, McCrory P. Medical issues in womensfootball. Br J Sports Med 2007;41(Suppl 1):i1.

. Dvorak J, McCrory P, Kirkendall DT. Head injuries in the femalefootball player: Incidence, mechanisms, risk factors and management.Br J Sports Med 2007;41 (Suppl 1): i44-i46.

. Jennett B, Bond M. Assessment of outcome after severe brain damage:A practical scale. Lancet 1975;1:480-484.

. Leninger B, Gramling S, Farrell A, Kreutzer J, Peck E. Neuropsycho-logical deficits in symptomatic minor head injury patients after con-cussion and mild concussion. J Neurol Neurosurg Psychiatry 1990;53:293-296.

. Lovell M, Iverson G, Collins M, McKeag D, Maroon J. Does loss ofconsciousness predict neuropsychological decrements after concus-sion. Clin J Sport Med 1999;9:193-199.

. McCrea M, Kelly J, Randolph C, Cisler R, Berger L. Immediateneurocognitive effects of concussion. Neurosurgery 2002;50:1032-1042.

. Cantu RC. Posttraumatic retrograde and anterograde amnesia: Patho-physiology and implications in grading and safe return to play. J AthlTrain 2001;36:244-248.

. Lovell MR, Collins MW, Iverson GL, et al. Recovery from mildconcussion in high school atheltes. J Neurosurg 2003;98:296-301.

. McCrory PR, Ariens T, Berkovic SF. The nature and duration of acuteconcussive symptoms in Australian football. Clin J Sport Med 2000;10:235-238.

. Yarnell P, Lynch S. The ding: amnestic state in football trauma.Neurology 1973;23:196-197.

. Yarnell PR, Lynch S. Retrograde memory immediately after concus-sion. Lancet 1970;I:863-864.

. McCrory PR, Berkovic SF. Video analysis of acute motor and convul-sive manifestations in sport-related concussion. Neurology 2000;54:1488-1491.

. McCrory PR, Bladin PF, Berkovic SF. Retrospective study of con-cussive convulsions in elite Australian rules and rugby league

footballers: Phenomenology, aetiology, and outcome. BMJ 1997;314:171-174.. Fleminger S. Long-term psychiatric disorders after traumatic braininjury. Eur J Anaesthesiol Suppl 2008;42:123-130.

. Chen JK, Johnston KM, Petrides M, Ptito A. Neural substrates ofsymptoms of depression following concussion in male athletes withpersisting postconcussion symptoms. Arch Gen Psychiatry 2008;65:81-89.

. Bryant RA. Disentangling mild traumatic brain injury and stressreactions. N Engl J Med 2008;358:525-527.

. Vanderploeg RD, Curtiss G, Luis CA, Salazar AM. Long-term morbid-ities following self-reported mild traumatic brain injury. J Clin ExpNeuropsychol 2007;29:585-598.

. Guskiewicz KM, Marshall SW, Bailes J, et al. Recurrent concussionand risk of depression in retired professional football players. Med SciSports Exerc 2007;39:903-909.

. Kashluba S, Casey JE, Paniak C. Evaluating the utility of ICD-10diagnostic criteria for postconcussion syndrome following mildtraumatic brain injury. J Int Neuropsychol Soc 2006;12:111-118.

. Iverson GL. Misdiagnosis of the persistent postconcussion syndromein patients with depression. Arch Clin Neuropsychol 2006;21:303-310.

. Chamelian L, Feinstein A. The effect of major depression on subjectiveand objective cognitive deficits in mild to moderate traumatic braininjury. J Neuropsychiatry Clin Neurosci 2006;18:33-38.

. Mooney G, Speed J, Sheppard S. Factors related to recovery after mildtraumatic brain injury. Brain Inj 2005;19:975-987.

. Broshek DK, Freeman JR. Psychiatric and neuropsychological issuesin sport medicine. Clin Sports Med 2005;24:663-679,x.

. Pellman EJ. Background on the National Football Leagues researchon concussion in professional football. Neurosurgery 2003;53:797-798.

. Purcell L, Carson J. Sport-related concussion in pediatric athletes.Clin Pediatr (Phila) 2008;47:106-113.

. Lee LK. Controversies in the sequelae of pediatric mild traumaticbrain injury. Pediatr Emerg Care 2007;23:580-583; quiz 4-6.

0. Schnadower D, Vazquez H, Lee J, Dayan P, Roskind CG. Controver-sies in the evaluation and management of minor blunt head trauma inchildren. Curr Opin Pediatr 2007;19:258-264.

1. Wozniak JR, Krach L, Ward E, et al. Neurocognitive and neuroim-aging correlates of pediatric traumatic brain injury: A diffusiontensor imaging (DTI) study. Arch Clin Neuropsychol 2007;22:555-568.

2. Hayden MG, Jandial R, Duenas HA, Mahajan R, Levy M. Pediatricconcussions in sports; a simple and rapid assessment tool forconcussive injury in children and adults. Childs Nerv Syst 2007;23:431-435.

3. Lee MA. Adolescent concussionsManagement recommendations: Apractical approach. Conn Med 2006;70:377-380.

4. Kirkwood MW, Yeates KO, Wilson PE. Pediatric sport-related con-cussion: A review of the clinical management of an oft-neglectedpopulation. Pediatrics 2006;117:1359-1371.

5. Guskiewicz KM, Marshall SW, Bailes J, et al. Association betweenrecurrent concussion and late-life cognitive impairment in retiredprofessional football players. Neurosurgery 2005;57:719-726; dis-cussion 726.

6. Nandoe RD, Scheltens P, Eikelenboom P. Head trauma and Alzhei-mers disease. J Alzheimers Dis 2002;4:303-308.

7. Stern MB. Head trauma as a risk factor for Parkinsons disease. MovDisord 1991;6:95-97.

8. Omalu BI, DeKosky ST, Hamilton RL, et al. Chronic traumatic en-cephalopathy in a national football league player: Part II. Neurosur-gery 2006;59:1086-1092; discussion 92-3.

9. Omalu BI, DeKosky ST, Minster RL, Kamboh MI, Hamilton RL,Wecht CH. Chronic traumatic encephalopathy in a National Foot-

ball League player. Neurosurgery 2005;57:128-134; discussion134.

11

11

11

11

11

11

11

11

11

11

12

12

12

12

12

12

12

12

12

12

13

13

13

13

13

13

13

13

13

13

14

14

14

14

14

14

14

14

14

14

15

15

15

15

15

15

15

268 McCrory et al ZURICH CONSENSUS STATEMENT ON CONCUSSION IN SPORT0. McKee AC, Cantu RC, Nowinski CJ, et al. Chronic traumatic enceph-alopathy in athletes: Progressive tauopathy after repetitive head in-jury. J Neuropathol Exp Neurol 2009;68:709-735.

1. McKee AC, Gavett BE, Stern RA, et al. TDP-43 Proteinopathy andmotor neuron disease in chronic traumatic encephalopathy. J Neuro-pathol Exp Neurol 2010;69;918-929.

2. McKee AC, Stein TD, Nowinski CJ, et al. The spectrum of disease inchronic traumatic encephalopathy. Brain 2013;136:43-64.

3. McCrory P. Sports concussion and the risk of chronic neurologicalimpairment. Clin J Sport Med 2011;21:6-12.

4. McCrory P. Future advances and areas of future focus in the treatmentof sport-related concussion. Clin Sports Med 2011;30:201-208, xi-ii.

5. Hagel BE, Pless IB, Goulet C, Platt RW, Robitaille Y. Effectiveness ofhelmets in skiers and snowboarders: Case-control and case crossoverstudy. BMJ 2005;330:281.

6. McCrory P. The role of helmets in skiing and snowboarding. Br JSports Med 2002;36:314.

7. Mueller BA, Cummings P, Rivara FP, Brooks MA, Terasaki RD.Injuries of the head, face, and neck in relation to ski helmet use.Epidemiology 2008;19:270-276.

8. Sulheim S, Holme I, Ekeland A, Bahr R. Helmet use and risk of headinjuries in alpine skiers and snowboarders. JAMA 2006;295:919-924.

9. Delaney JS, Al-Kashmiri A, Drummond R, Correa JA. The effect of protectiveheadgear on head injuries and concussions in adolescent football (soccer)players. Br J Sports Med 2008;42:110-115; discussion 5.

0. Viano DC, Pellman EJ, Withnall C, Shewchenko N. Concussion inprofessional football: Performance of newer helmets in reconstructedgame impactsPart 13. Neurosurgery 2006;59:591-606; discussion591-606.

1. Finch C, Braham R, McIntosh A, McCrory P, Wolfe R. Should footballplayers wear custom fitted mouthguards? Results from a group ran-domised controlled trial. Inj Prev 2005;11:242-246.

2. McIntosh A, McCrory P. The dynamics of concussive head impacts in rugbyand Australian rules football. Med Sci Sports Exerc 2000;32:1980-1985.

3. McIntosh A, McCrory P. Impact energy attenuation performance offootball headgear. Br J Sports Med 2000;34:337-342.

4. McIntosh A, McCrory P. Effectiveness of headgear in a pilot study ofunder 15 rugby union football. Br J Sports Med 2001;35:167-170.

5. McIntosh A, McCrory P, FInch C, Best J, Chalmers D. Rugby Head-gear Study. J Sci Med Sport 2003;6:355-358.

6. Finch C, Newstead S, Cameron M, Vulcan A. Head injury reductionsin Victoria two years after the introduction of mandatory bicyclehelmet use. Report no. 51, July, 1993. Melbourne, Australia: MonashUniversity Accident Research Centre; 1993.

7. Curnow WJ. Bicycle helmets and public health in Australia. HealthPromot J Austr 2008;19:10-15.

8. Hewson PJ. Cycle helmets and road casualties in the UK. Traffic InjPrev 2005;6:127-134.

9. Davidson JA. Epidemiology and outcome of bicycle injuries present-ing to an emergency department in the United Kingdom. Eur J EmergMed 2005;12:24-29.

0. Hansen KS, Engesaeter LB, Viste A. Protective effect of different typesof bicycle helmets. Traffic Inj Prev 2003;4:285-290.

1. Andersen T, Arnason A, Engebretsen L, Bahr R. Mechanism of headinjuries in elite football. Br J Sports Med 2004;38:690-696.

2. Hagel B, Meewisse W. Editorial: Risk compensation: A Side effect ofsport injury prevention? Clin J Sport Med. 2004;14:193-196.

3. Finch C, Mcintosh AS, McCrory P, Zazryn T. A pilot study of theattitudes of Australian Rules footballers towards protective headgear.J Sci Med Sport 2003;6:505-511.

4. Finch CF, McIntosh AS, McCrory P. What do under 15 year old

schoolboy rugby union players think about protective headgear? Br JSports Med 2001;35:89-94.5. Finch C, Mcintosh AS, McCrory P. What is the evidence base for theuse of protective headgear and mouthguards in Australian football.Sport Health 2000;18:35-38.

6. Reece RM, Sege R. Childhood head injuries: Accidental or inflicted?Arch Pediatr Adolesc Med 2000;154:11-15.

7. Shaw NH. Bodychecking in hockey. CMAJ 2004;170:15-16; authorreply 6, 8.

8. Denke NJ. Brain injury in sports. J Emerg Nurs 2008;34:363-364.

9. Gianotti S, Hume PA. Concussion sideline management interventionfor rugby union leads to reduced concussion claims. NeuroRehabili-tation 2007;22:181-189.

0. Guilmette TJ, Malia LA, McQuiggan MD. Concussion understandingand management among New England high school football coaches.Brain Inj 2007;21:1039-1047.

1. Hootman JM, Dick R, Agel J. Epidemiology of collegiate injuries for 15sports: Summary and recommendations for injury prevention initia-tives. J Athl Train 2007;42:311-319.

2. Valovich McLeod TC, Schwartz C, Bay RC. Sport-related concussionmisunderstandings among youth coaches. Clin J Sport Med 2007;17:140-142.

3. Sye G, Sullivan SJ, McCrory P. High school rugby players under-standing of concussion and return to play guidelines. Br J Sports Med2006;40:1003-1005.

4. Theye F, Mueller KA. Heads up: Concussions in high school sports.Clin Med Res 2004;2:165-171.

5. Kashluba S, Paniak C, Blake T, Reynolds S, Toller-Lobe G, Nagy J. Alongitudinal, controlled study of patient complaints following treatedmild traumatic brain injury. Arch Clin Neuropsychol 2004;19:805-816.

6. Gabbe B, Finch CF, Wajswelner H, Bennell K. Does community-levelAustralian football support injury prevention research? J Sci MedSport 2003;6:231-236.

7. Kaut KP, DePompei R, Kerr J, Congeni J. Reports of head injury andsymptom knowledge among college athletes: Implications for assess-ment and educational intervention. Clin J Sport Med 2003;13:213-221.

8. Davidhizar R, Cramer C. The best thing about the hospitalization wasthat the nurses kept me well informed Issues and strategies of clienteducation. Accid Emerg Nurs 2002;10:149-154.

9. McCrory P. What advice should we give to athletes postconcussion?Br J Sports Med 2002;36:316-318.

0. Bazarian JJ, Veenema T, Brayer AF, Lee E. Knowledge of concussionguidelines among practitioners caring for children. Clin Pediatr(Phila) 2001;40:207-212.

1. Guskiewicz KM, Weaver NL, Padua DA, Garrett WE Jr. Epidemiologyof concussion in collegiate and high school football players. Am JSports Med 2000;28:643-650.

2. McCrea M, Guskiewicz KM, Marshall SW, et al. Acute effects andrecovery time following concussion in collegiate football players: TheNCAA Concussion Study. JAMA 2003;290:2556-2563.

3. Macciocchi SN, Barth JT, Alves W, Rimel RW, Jane JA. Neuropsycho-logical functioning and recovery after mild head injury in collegiateathletes. Neurosurgery 1996;39:510-514.

4. Meehan WP III, dHemecourt P, Comstock RD. High school concus-sions in the 2008-2009 academic year: Mechanism, symptoms, andmanagement. Am J Sports Med 2010;38:2405-2409.

5. Eckner JT, Kutcher JS, Richardson JK. Between-seasons test-retest reliabilityof clinically measured reaction time in National Collegiate Athletic Associa-tion Division I athletes. J Athl Train 2011;46:409-414.

6. Eckner JT, Richardson JK, Kim H, Lipps DB, Ashton-Miller JA. A

novel clinical test of recognition reaction time in healthy adults.Psychol Assess 2012;24:249-254.

Foo

WriP.Mberg

AuthDiscfundintoPrevOlymreceJousciespocon(whcofoComcomrece

W.HKineCalgDiscInstFooHotIntesupspoconeditsupconholdsup

M.AMedCanDiscmeefina

R.CTrauDiscEquUSAtestman

J.D.SwitlandDiscor grela

R.JAdjuDiscMajconthe New Jersey Commission on Brain Injury Research; maintains a private practicefocutionto th

L.E.of MOsloLauDiscInstAssResthedepeditdire

K.MManDiscspoFunThinhadnot

J.SogyDiscneuAssPromemconandNeuman

M.RDisc

A.SderbUSADiscunpencclinneudire

B.WFacMedDiscMedClinTecman

G.AInstDiscdire

R.ENeuNecDisc

K.MScieCenDisclosure: serves on NCAAs Health and Safety Advisory Committee for Concussion,

269PM&R Vol. 5, Iss. 4, 2013sed on clinical neuropsychology, sports neuropsychology, and forensic applica- NFLs Head Neck and Spine Committee, and NFLPAs Mackey-White Committee;tnotes Continued From Page 255.

ting Group. Associate Professor, The Florey Institute of Neuroscience and Mental Health, Heidel-, Australia. Address correspondence to: P.M.; e-mail:

or affiliations can be found on page 269.losure: co-investigator, collaborator, consultant on grants relating to mild TBIed by several governmental organizations; co-chair, Australian Centre for ResearchSports Injury and its Prevention, one of the International Research Centres forention of Injury and Protection of Athlete Health supported by the Internationalpic Committee; clinical and consulting practice in general and sports neurology;ives book royalties, McGraw-Hill; employed in an editorial capacity, British Medicalrnal Publishing Group, 2001-2008; reimbursed by the government, professionalntific bodies, and sporting bodies for presenting research relating to mild TBI andrt-related concussion at meetings, scientific conferences, and symposiums; receivedsultancy fees, 2010, Axon Sports (US) for development of educational materialich was not renewed); received research funding since 2005, CogState Inc.;under and shareholder in 2 biomedical companies (involved in eHealth andpression garment technologies) but does not hold any individual shares in anypany related to concussion or brain injury assessment or technology. He did notive any form of financial support directly related to this manuscript.

.M. Professor and Co-chair, Sport Injury Prevention Research Centre, Faculty ofsiology and Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary,ary, Alberta, Canadalosure: received research grant support, University of Calgary from the Canadianitutes of Health Research, Alberta Innovates Health Solutions, the Internationaltball Association (FIFA), Alberta Childrens Hospital Research Institute, and thechkiss Brain Institute; co-chair, Sport Injury Prevention Research Centre, one of thernational Research Centres for Prevention of Injury and Protection of Athlete Healthported by the International Olympic Committee; clinical and consulting practice inrt medicine, University of Calgary Sport Medicine Centre, focus on sport relatedcussion; received travel funding, FIFA and the Medical Commission of the IOC;or-in-chief, 1998-2012, Clinical Journal of Sport Medicine and received editorialport funding, Lippincott-Wolters Kluwer; receives compensation as a medicalsultant, National Hockey League; may receive royalty, BKIN Technologies; share-er, Safebrain Canada and PrivIT Healthcare. He did not receive any form of financialport directly related to this manuscript.

. Chief Medical Officer, International Ice Hockey Federation, Switzerland; Member of the IOCical Commission Games Group; Co-director, Ottawa Sport Medicine Centre, Ottawa, Ontario,adalosure: receives travel funding, IIHF and IOC Medical Commission Games Group fortings, IIHF Championships, and Olympic Games. He did not receive any form ofncial support directly related to this manuscript.

.C. Clinical Professor, Neurosurgery and Co-director, Center for the Study ofmatic Encephalopathy, Boston University Medical Center, Boston, MAlosure: vice president, National Operating Committee on Standards for Athleticipment; co-founder and chairman medical director, Sports Legacy , Waltham, MA,; senior advisor, NFLs Head, Neck and Spine Committee; expert witness, trialimony. He did not receive any form of financial support directly related to thisuscript.

Professor of Neurology, University of Zurich; Senior Consultant, Schulthess Clinic Zurich,zerland; Chairman F-MARC (FIFA Medical Assessment and Research Center) Zurich Switzer-

losure: received compensation, chief medical officer, FIFA. No other compensationsrants have been received. He did not receive any form of financial support directlyted to this manuscript.

.E. Psychological and Neurobehavioral Associates, Inc, State College, PA, USA;nct Associate Professor of Psychology, University of Missouri, Kansas City, MO, USAlosure: receives financial compensation, consultant, National Hockey League,or League Soccer, and the U.S. Soccer Federation; receives financial compensation,sultant, Princeton University; served as PI or co-PI on grants, NOCSAE, AMSSM, ands of neuropsychology. He did not receive any form of financial support directly relatedis manuscript.

receprofProfessor, Department of Orthopaedic Surgery, Oslo University Hospital and Facultyedicine, University of Oslo, Norway; Co-chair, Oslo Sports Trauma Research Center,, Norway; Head, Scientific Activities, International Olympic Committee (IOC),sanne Switzerlandlosure: received research grant support, University of Oslo from the Norwegianitutes of Health Research, The Health South East, the International Footballociation; co-chair, Sport Injury Prevention Research Centre, one of the Internationalearch Centres for Prevention of Injury and Protection of Athlete Health supported byInternational Olympic Committeel; professor and chair, Oslo University Orthopedicartment; 2008-present, editor-in-chief, BJSM IPHP; January 2012-present, co-or, The Journal of Bone and Joints. He did not receive any form of financial supportctly related to this manuscript.

.J. Neurosurgeon, Division of Neurosurgery, University of Toronto; Concussionagement Program, Athletic Edge Sports Medicine, Toronto, Canadalosure: neurosurgeon subspecialized in brain trauma; clinical and research focus inrt concussion; received research funding through the CIHR, ONF, and Innovationd, American College of Surgeons, McGill University, Pashby Sport Safety Fund, andk First Canada; independent consultant, many sport organizations. She has nevera formal reimbursed affiliation with any sport team or sport governing body. She didreceive any form of financial support directly related to this manuscript.

.K. Associate Professor and Director, Michigan NeuroSport, Department of Neurol-,