Considerations for return-to-play and retirement decisions after concussion

When should an athlete retire or discontinue participating in contact or collision sports following sport-related concussion? A systematic review

OBJECTIVE

To systematically review the scientific literature regarding factors to consider when providing advice or guidance to athletes about retirement from contact or collision sport following sport-related concussion (SRC), and to define contraindications to children/adolescent athletes entering or continuing with contact or collision sports after SRC.

DATA SOURCES

Medline, Embase, SPORTSDiscus, APA PsycINFO, CINAHL and Cochrane Central Register of Controlled Trials were searched systematically.

STUDY ELIGIBILITY CRITERIA

Studies were included if they were (1) original research, (2) reported on SRC as the primary source of injury, (3) evaluated the history, clinical assessment and/or investigation of findings that may preclude participation in sport and (4) evaluated mood disturbance and/or neurocognitive deficits, evidence of structural brain injury or risk factors for increased risk of subsequent SRC or prolonged recovery.

RESULTS

Of 4355 articles identified, 93 met the inclusion criteria. None of the included articles directly examined retirement and/or discontinuation from contact or collision sport. Included studies examined factors associated with increased risk of recurrent SRC or prolonged recovery following SRC. In general, these were low-quality cohort studies with heterogeneous results and moderate risk of bias. Higher number and/or severity of symptoms at presentation, sleep disturbance and symptom reproduction with Vestibular Ocular Motor Screen testing were associated with prolonged recovery and history of previous concussion was associated with a risk of further SRC.

CONCLUSION

No evidence was identified to support the inclusion of any patient-specific, injury-specific or other factors (eg, imaging findings) as absolute indications for retirement or discontinued participation in contact or collision sport following SRC.

PROSPERO REGISTRATION NUMBER

CRD42022155121.

Long-term effects of multiple concussions on prefrontal cortex oxygenation during neurovascular coupling activation in retired male contact sport athletes

Purpose

This study aimed to investigate the long-term effects of multiple concussions on prefrontal cortex oxygenation during a neurovascular coupling activating task using near infrared spectroscopy (NIRS).

Methods

Self-reported physically active males who previously participated in contact team sports at various levels of competition and who previously had experienced at least 3 concussions (n = 55; mTBI) or had no history of concussions (n = 29; CTRL) were recruited. Participants completed a 5 min "Where's Waldo" object identification protocol which consisted of participants closing their eyes for 20-s followed by 40-s (repeated 5 times over 5-min) of searching a computer screen for "Waldo" hidden in a field of distractors. NIRS (μM) was used to measure right and left prefrontal cortex cerebral oxygenation. Oxygenated (O2Hb), deoxygenated (HHb), total (tHb) haemoglobin, and haemoglobin difference (HbDiff) were analysed through the change in average maximal and minimal values (ΔMAX), Z-scores, and standard deviations.

Results

There were no significant differences in the relative change in cerebral oxygenation of the right prefrontal cortex between groups. In mTBI, left prefrontal cortex HHb ΔMAX (p = 0.031) and tHb ΔMAX (p = 0.044) were significantly lower than in the CTRL group. Within-group, right vs. left prefrontal cortex differences showed significantly lower values in left HbDiff Z-scores (p = 0.019) in only the mTBI group while the CTRL group showed significantly lower values in left HbDiff SD (p = 0.045).

Conclusion

This preliminary study suggests that there are changes in prefrontal cortex oxygenation in males who had a history of experiencing multiple concussions in their past during a neurovascular coupling activating task. These changes may represent potential long-term effects in the brain's ability to adapt cerebral oxygenation during increased neural activity.

Overview of Traumatic Brain Injury in American Football Athletes

OBJECTIVE

The aim of this review is to provide a summary of the epidemiology, clinical presentation, pathophysiology, and treatment of traumatic brain injury in collision athletes, particularly those participating in American football.

DATA SOURCES

A literature search was conducted using the PubMed/MEDLINE and Google Scholar databases for publications between 1990 and 2019. The following search phrases were used: "concussion," "professional athletes," "collision athletes," "mild traumatic brain injury," "severe traumatic brain injury," "management of concussion," "management of severe traumatic brain injury," and "chronic traumatic encephalopathy." Publications that did not present epidemiology, clinical presentation, pathophysiology, radiological evaluation, or management were omitted. Classic articles as per senior author recommendations were retrieved through reference review.

RESULTS

The results of the literature review yielded 147 references: 21 articles discussing epidemiology, 16 discussing clinical presentation, 34 discussing etiology and pathophysiology, 10 discussing radiological evaluation, 34 articles for on-field management, and 32 articles for medical and surgical management.

CONCLUSION

Traumatic brain injuries are frequent in professional collision athletes, and more severe injuries can have devastating and lasting consequences. Although sport-related concussions are well studied in professional American football, there is limited literature on the epidemiology and management of severe traumatic brain injuries. This article reviews the epidemiology, as well as the current practices in sideline evaluation, acute management, and surgical treatment of concussions and severe traumatic brain injury in professional collision athletes. Return-to-play decisions should be based on individual patient symptoms and recovery.

Biomarkers to aid the return to play decision following sports-related concussion: a systematic review

Premature return to play (RTP) following sports-related concussion (SRC) is associated with significant morbidity including risk of neurological and non-neurological injury, persistent post-concussion symptoms and chronic neurological deficits. Assessing athletes for RTP is critical but these decisions are currently based on clinical assessments that are subject to bias and symptomatic reporting that rely on compliance. An objective and easily obtained biomarker that can indicate recovery following SRC would aid clinicians to make safer RTP decisions. We performed a systematic review to identify potential biomarkers from saliva, urine and blood sources that could inform the clinical RTP decision. The MEDLINE database was searched. Inclusion criteria were studies focusing on adults diagnosed with SRC, fluid biomarkers from blood, saliva or urine and clinical recovery from SRC or at RTP. We assessed each biomarker for their time course post SRC and relationship to clinical recovery. Secondary outcomes included correlation with symptom scores and predictive value for prolonged RTP. We identified 8 studies all investigating blood-based markers of diffuse axonal injury (tau, NFL, SNTF), neuroglial injury (NSE, VLP-1, UCH-L1, S100B, GFAP), inflammation and hormonal disturbances. Tau, SNTF, UCH-1, GFAP, S100B and the inflammatory cytokine MCP-4 are raised post SRC and return to baseline by RTP. Changes in tau, NFL, SNTF, GFAP and MCP-4 post SRC correlate with severity of concussion as measured by symptom severity or RTP duration. There is only preliminary case-reporting for hormonal biomarkers. The evidence is limited by a lack of highly powered studies, variation in use of athletic and Contact sport controls (CSC) and a lack of consistent sampling and assessment protocols. There is promise for biomarkers to aid RTP decisions following SRC, most notably in use alongside clinical assessment in RTP criteria to allow greater precision in identifying mild and severe concussion.

Considerations for Pediatric Retirement from Athletics Following Repetitive Concussive Traumatic Brain Injury: Incorporating the Right to an Open Future

Guidance regarding the decision to remove an adolescent from athletic competition immediately following an acute concussive injury and the safe return of play in the short term is widely accepted and supported by clinical evidence, local institutional policies, and state and federal laws. There is considerably less guidance regarding the decision to permanently retire an adolescent athlete for medical reasons due to concussive injuries. In this article, we discuss the clinical and non-clinical considerations that should guide clinicians in discussions regarding the adolescent athlete’s permanent retirement by emphasizing the ethical obligation to protect the child’s right to an open future as possibly determinative in otherwise ambiguous cases.

Considerations for Athlete Retirement After Sport-Related Concussion

The recommendation to retire from sport after concussion has evolved with the understanding of concussion. Age, sport, position, level of play, relevant medical and concussion history, severity and duration of symptoms, neuroimaging and neuropsychological testing should all be considered. Susceptibility to injury, persistence of symptoms, psychological distress, and personal values and support may also play a role. Pediatric athletes may require a more conservative approach, given ongoing growth and development. For professional and/or elite athletes, financial or career implications may be considerations. When possible, retirement should be a shared decision among the athlete, the family, and the health care team.

Primary care management of concussion in Canada

Concussion has emerged as an important public health issue affecting thousands of Canadians annually. Health care providers including paediatricians, family and emergency medicine physicians, nurses, and nurse practitioners are commonly tasked with the responsibility of providing primary care to patients with acute concussion and those with persistent post-concussion symptoms. In July 2017, Parachute, in collaboration with the Public Health Agency of Canada and Sport Canada released the Canadian Guideline on Concussion in Sport that outlines a standardized and evidence-based approach to the recognition, diagnosis, and management of youth and adults with suspected concussion. In this report, we provide a brief overview of the important roles of primary care providers in the medical assessment, management, and prevention of concussion as outlined in this national best practice guideline.

Sport-Related Concussion in Children and Adolescents

Sport-related concussion is an important topic in nearly all sports and at all levels of sport for children and adolescents. Concussion knowledge and approaches to management have progressed since the American Academy of Pediatrics published its first clinical report on the subject in 2010. Concussion's definition, signs, and symptoms must be understood to diagnose it and rule out more severe intracranial injury. Pediatric health care providers should have a good understanding of diagnostic evaluation and initial management strategies. Effective management can aid recovery and potentially reduce the risk of long-term symptoms and complications. Because concussion symptoms often interfere with school, social life, family relationships, and athletics, a concussion may affect the emotional well-being of the injured athlete. Because every concussion has its own unique spectrum and severity of symptoms, individualized management is appropriate. The reduction, not necessarily elimination, of physical and cognitive activity is the mainstay of treatment. A full return to activity and/or sport is accomplished by using a stepwise program while evaluating for a return of symptoms. An understanding of prolonged symptoms and complications will help the pediatric health care provider know when to refer to a specialist. Additional research is needed in nearly all aspects of concussion in the young athlete. This report provides education on the current state of sport-related concussion knowledge, diagnosis, and management in children and adolescents.

Medical retirement from sport after concussions: A practical guide for a difficult discussion

Purpose of review

In patients with a considerable history of sports-related concussion, the decision of when to discontinue participation in sports due to medical concerns including neurologic disorders has potentially life-altering consequences, especially for young athletes, and merits a comprehensive evaluation involving nuanced discussion. Few resources exist to aid the sports medicine provider.

Recent findings

In this narrative review, we describe 10 prototypical vignettes based upon the authors' collective experience in concussion management and propose an algorithm to help clinicians navigate retirement discussions. Issues for consideration include absolute and relative contraindications to return to sport, ranging from clinical or radiographic evidence of lasting neurologic injury to prolonged concussion recovery periods or reduced injury threshold to patient-centered factors including personal identity through sport, financial motivations, and navigating uncertainty in the context of long-term risks.

Summary

The authors propose a novel treatment algorithm based on real patient cases to guide medical retirement decisions after concussion in sport.

Concussions in NCAA Varsity Football Athletes: A Qualitative Investigation of Player Perception and Return to Sport

Background

The objective of this study was to understand the experiences and perspectives of varsity football athletes on return to play following a concussion injury.

Methods

Two experienced interviewers conducted qualitative, semistructured interviews of college-level football players who had sustained at least one concussion during their varsity careers.

Results

Twenty varsity football players who averaged 2.3 concussions each (range, 1-5) were interviewed regarding peer pressure, the culture of football, and player awareness as factors affecting return to sport following a concussion. Less common secondary factors included risk management, severity and timing of the injury, and team support.

Conclusions

Psychological stressors, the culture of football, and increased awareness were the most influential factors affecting collegiate football players' deciding to return to sport following a concussion.

Level of Evidence

Level III.

Prevalence of Abnormal Magnetic Resonance Imaging Findings in Children with Persistent Symptoms after Pediatric Sports-Related Concussion

A subset of patients experience persistent symptoms after pediatric concussion, and magnetic resonance imaging (MRI) is commonly used to evaluate for pathology. The utility of this practice is unclear. We conducted a retrospective cohort study to describe the MRI findings in children with concussion. A registry of all patients seen at our institution from January 2010 through March 2016 with pediatric sports-related concussion was cross-referenced with a database of radiographical studies. Radiology reports were reviewed for abnormal findings. Patients with abnormal computed tomographies or MRI scans ordered for reasons other than concussion were excluded. Among 3338 children identified with concussion, 427 underwent MRI. Only 2 (0.5%) had findings compatible with traumatic injury, consisting in both of microhemorrhage. Sixty-one patients (14.3%) had abnormal findings unrelated to trauma, including 24 nonspecific T₂ changes, 15 pineal cysts, eight Chiari I malformations, and five arachnoid cysts. One child underwent craniotomy for a cerebellar hemangioblastoma after presenting with ataxia; another had cortical dysplasia resected after seizure. The 2 patients with microhemorrhage each had three previous concussions, significantly more than patients whose scans were normal (median, 1) or abnormal without injury (median, 1.5; p = 0.048). MRI rarely revealed intracranial injuries in children post-concussion, and the clinical relevance of these uncommon findings remains unclear. Abnormalities unrelated to trauma are usually benign. However, MRI should be thoughtfully considered in children who present with concerning or atypical symptoms.

Concussion Care Practices and Utilization of Evidence-Based Guidelines in the Evaluation and Management of Concussion: A Survey of New England Emergency Departments

Evidence-based clinical practice guidelines can facilitate proper evaluation and management of concussions in the emergency department (ED), often the initial and primary point of contact for concussion care. There is no universally adopted set of guidelines for concussion management, and extant evidence suggests that there may be variability in concussion care practices and limited application of clinical practice guidelines in the ED. This study surveyed EDs throughout New England to examine current practices of concussion care and utilization of evidence-based clinical practice guidelines in the evaluation and management of concussions. In 2013, a 32-item online survey was e-mailed to 149/168 EDs throughout New England (Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, Maine). Respondents included senior administrators asked to report on their EDs use of clinical practice guidelines, neuroimaging decision-making, and discharge instructions for concussion management. Of the 72/78 respondents included, 35% reported absence of clinical practice guidelines, and 57% reported inconsistency in the type of guidelines used. Practitioner preference guided neuroimaging decision-making for 57%. Although 94% provided written discharge instructions, there was inconsistency in the recommended time frame for follow-up care (13% provided no specific time frame), the referral specialist to be seen (25% did not recommend any specialist), and return to activity instructions were inconsistent. There is much variability in concussion care practices and application of evidence-based clinical practice guidelines in the evaluation and management of concussions in New England EDs. Knowledge translational efforts will be critical to improve concussion management in the ED setting.

Retirement and Activity Restrictions Following Concussion

Sport-related concussion is prevalent at all levels of play. Increased attention from sports media and scientific and medical communities has prompted players and physicians to explore the long-term effects of concussion and ask the questions of when and how players should begin to mitigate their concussion risk. The authors evaluate their risks from the perspective of epidemiology, symptomatology, neuropsychological performance, and biomechanics. The authors propose that there is not a set number of concussions that necessitates retirement in athletes and, aside from a few absolute contraindications to return to collision sport, return to play should be an individualized process.

Retirement-from-sport considerations following pediatric sports-related concussion: case illustrations and institutional approach

The decision to advise an athlete to retire from sports following sports-related concussion (SRC) remains a persistent challenge for physicians. In the absence of strong empirical evidence to support recommendations, clinical decision making must be individualized and should involve a multidisciplinary team of experts in concussion and traumatic brain injury. Although previous authors have advocated for a more conservative approach to these issues in child and adolescent athletes, there are few reports outlining considerations for this process among this unique population. Here, the authors use multiple case illustrations to discuss 3 subgroups of clinical considerations for sports retirement among pediatric SRC patients including the following: those with structural brain abnormalities identified on neuroimaging, those presenting with focal neurological deficits and abnormalities on physical examination, and those in whom the cumulative or prolonged effects of concussion are suspected or demonstrated. The authors' evolving multidisciplinary institutional approach to return-to-play and retirement decision making in pediatric SRC is also presented.

Sports-Related Concussion

Sports-related concussions (SRC) are common in all ages and occur in all sports. The diagnosis based on clinical suspicion after more serious injury is ruled out. Symptoms of concussion are due to a temporary and reversible neurometabolic cascade resulting in blood flow changes, neuronal excitotoxicity, ionic shifts, and mitochondrial changes. Symptoms are nonspecific, and commonly include headache, cognitive complaints, photophobia, and phonophobia. Loss of consciousness is rare in SRC and has limited influence on recovery and prognosis. Imaging has a limited role in the management of concussion and should be used to evaluate for more serious intracranial pathology. Treatment is based on symptoms and an understanding of the typical, rapid (7-10 days) recovery. No athlete should return to play until their symptoms have resolved and they have completed a supervised, step-wise return to play protocol. The article covers the most recent literature on the diagnosis and management of SRC, including evidence-based recommendations and expert-based consensus opinion. The article will also discuss issues regarding medical retirement, legislation, and future concepts in concussion diagnosis and management.

Neuroimaging findings in pediatric sports-related concussion

OBJECT

The goal in this review was to summarize the results of clinical neuroimaging studies performed in patients with sports-related concussion (SRC) who were referred to a multidisciplinar ypediatric concussion program.

METHODS

The authors conducted a retrospective review of medical records and neuroimaging findings for all patients referred to a multidisciplinary pediatric concussion program between September 2013 and July 2014. Inclusion criteria were as follows: 1) age ≤ 19 years; and 2) physician-diagnosed SRC. All patients underwent evaluation and follow-up by the same neurosurgeon. The 2 outcomes examined in this review were the frequency of neuroimaging studies performed in this population (including CT and MRI) and the findings of those studies. Clinical indications for neuroimaging and the impact of neuroimaging findings on clinical decision making were summarized where available. This investigation was approved by the local institutional ethics review board.

RESULTS

A total of 151 patients (mean age 14 years, 59% female) were included this study. Overall, 36 patients (24%) underwent neuroimaging studies, the results of which were normal in 78% of cases. Sixteen percent of patients underwent CT imaging; results were normal in 79% of cases. Abnormal CT findings included the following: arachnoid cyst (1 patient), skull fracture (2 patients), suspected intracranial hemorrhage (1 patient), and suspected hemorrhage into an arachnoid cyst (1 patient). Eleven percent of patients underwent MRI; results were normal in 75% of cases. Abnormal MRI findings included the following: intraparenchymal hemorrhage and sylvian fissure arachnoid cyst (1 patient); nonhemorrhagic contusion (1 patient); demyelinating disease (1 patient); and posterior fossa arachnoid cyst, cerebellar volume loss, and nonspecific white matter changes (1 patient).

CONCLUSIONS

Results of clinical neuroimaging studies are normal in the majority of pediatric patients with SRC. However, in selected cases neuroimaging can provide information that impacts decision making about return to play and retirement from the sport.

The Diagnosis and Management of Concussion in Children and Adolescents

BACKGROUND

Concussion is a complex brain injury that results in more than 100,000 emergency department visits for school-aged children each year in the United States. All 50 US states have passed concussion legislation designed to promote safety in youth sports. Most of these laws require medical clearance by a licensed health care provider before returning to sport, which may have contributed to an increase in pediatric subspecialty referrals, particularly referrals to the child neurologist.

METHODS

We reviewed the literature on pediatric concussion.

RESULTS

This review summarizes the current knowledge and recommendations for concussion diagnosis and management in children and adolescents, athletes and nonathletes. It highlights concussion epidemiology, pathophysiology, advances in neuroimaging, and potential health risks including second impact syndrome and chronic traumatic encephalopathy. It also underscores clinical areas where evidence is lacking.

CONCLUSIONS

The diagnosis and management of concussion requires specific considerations in children. Further concussion research must be done to minimize injury risk and to optimize medical care for this common problem.

A Balanced Protocol for Return to School for Children and Youth Following Concussive Injury

BACKGROUND

Few protocols exist for returning children/youth to school after concussion. Childhood concussion can significantly affect school performance, which is vital to social development, academic learning, and preparation for future roles. The goal of this knowledge translation research was to develop evidence based materials to inform physicians about pediatric concussion.

METHODS

The Return to School (RTS) concussion protocol was developed following the National Institute for Health and Care Excellence procedures.

RESULTS

Based on a scoping review, and stakeholder opinions, an RTS protocol was developed for children/youth. This unique protocol focuses on school adaptation in 4 main areas: (a) timetable/attendance, (b) curriculum, (c) environmental modifications, and (d) activity modifications.

CONCLUSION

A balance of cognitive rest and timely return to school need to be considered for returning any student to school after a concussion. Implementation of these new recommendations may be an important tool in prevention of prolonged absence from school and academic failure while supporting brain recovery.

Evaluation of the anatomical and functional consequences of repetitive mild cervical contusion using a model of spinal concussion

Spinal cord concussion is characterized by a transient loss of motor and sensory function that generally resolves without permanent deficits. Spinal cord concussions usually occur during vehicular accidents, falls, and sport activity, but unlike brain concussions, have received much less attention despite the potential for repeated injury leading to permanent neurological sequelae. Consequently, there is no consensus regarding decisions related to return to play following an episode of spinal concussion, nor an understanding of the short- and long-term consequences of repeated injury. Importantly, there are no models of spinal concussion to study the anatomical and functional sequelae of single or repeated injury. We have developed a new model of spinal cord concussion focusing on the anatomical and behavioral outcomes of single and repeated injury. Rats received a very mild (50 kdyn, IH impactor) spinal contusion at C5 and were separated into two groups three weeks after the initial injury--C1, which received a second, sham surgery, and C2, which received a second contusion at the same site. To track motor function and recovery, animals received weekly behavioral tests--BBB, CatWalk™, cylinder, and Von Frey. Analysis of locomotor activity by BBB demonstrated that rats rapidly recovered, regaining near-normal function by one week after the first and second injury, which was confirmed using the more detailed CatWalk™ analysis. The cylinder test showed that a single contusion did not induce significant deficits of the affected limb, but that repeated injury resulted in significant alteration in paw preference, with animals favoring the unaffected limb. Intriguingly, Von Frey analysis demonstrated an increased sensitivity in the contralateral hindlimb in the C2 group vs. the C1 group. Anatomical analyses revealed that while the lesion volume of both groups was minimal, the area of spared white matter in the C2 group was significantly reduced 1 and 2mm rostral to the lesion epicenter. Reactive astrocytes were present in both groups, with the majority found at the lesion epicenter in the C1 group, whereas the C2 group demonstrated increased reactive astrocytes extending 1mm caudal to the lesion epicenter. Macrophages accumulated within the injured, dorsal and ipsilateral spinal cord, with significant increases at 2 and 3mm rostral to the epicenter in the C2 group. Our model is designed to represent the clinical presentation of spinal cord concussion, and highlight the susceptibility and functional sequelae of repeated injury. Future experiments will examine the temporal and spatial windows of vulnerability for repeated injuries.

Development of a conservative protocol to return children and youth to activity following concussive injury

BACKGROUND

Consensus-based guidelines exist for adult athletes returning to play after concussion, but there are no protocols developed specifically for children. The goal of this knowledge translation research was to develop evidence-based materials to inform physicians about pediatric concussion.

METHODS

A pediatric concussion protocol was developed based on the National Institute for Health and Care Excellence procedures.

RESULTS

This return to activity protocol was developed to guide management when children/youth sustain a concussion. The protocol incorporated 3 main themes: (a) a protocol must include return to all activity, including sport and school; (b) existing consensus-based adult protocols are not appropriate for children; and (c) a more conservative protocol is needed. After pilot testing, the developed protocol is being used across Ontario.

CONCLUSION

Implementation of these new pediatric recommendations is an important addition to prevention of subsequent concussions during vulnerable recovery periods, with potential to facilitate recovery by preventing prolonged symptomatology, and secondary sequelae.

Post-concussion return to play and return to school guidelines for children and youth: a scoping methodology

PURPOSE

The objective of this study was to identify and describe management strategies to ensure safe return to activity (RTA) and return to school (RTS) of children with mild traumatic brain injury (MTBI) and determine whether they are evidence-based.

METHODS

A scoping methodology was conducted using research published between 1990 and 2013, gray literature and clinical expertise. Once the data had been charted, an expert panel of physicians and clinicians was consulted to inform and validate study findings. An analytical and thematic framework was used to examine the study findings.

RESULTS

A total of 400 potentially relevant published articles, 100 websites and 24 iPad Applications were found. Ten articles and three web-based resources met inclusion criteria and were included in the final review. Nine articles recommended a more conservative approach to RTA, as well as identified a step-wise or severity-oriented approach. General recommendations were also found regarding safe RTS. One study recommended a stepwise RTS protocol for children.

CONCLUSIONS

This scoping methodology determined that the most comprehensive guidelines for management are focused on adults. Evidence concerning prolonged recovery patterns in children and the impact of concussion on the developing brain suggests that pediatric-specific guidelines are needed for RTA and RTS after MTBI/concussion.

IMPLICATIONS FOR REHABILITATION

Although concussion in children is an increasing concern, it has been determined that the most comprehensive guidelines for management are focused on adults. These guidelines are primarily consensus-based and are not proven fact through quality research. Evidence concerning prolonged recovery patterns in youth and the impact of concussion on the developing brain suggest that pediatric guidelines should be more conservative than for adults. Therefore, pediatric-specific guidelines need to be developed for return to activity and return to school after MTBI/concussion.

National Athletic Trainers' Association position statement: management of sport concussion

OBJECTIVE

To provide athletic trainers, physicians, and other health care professionals with best-practice guidelines for the management of sport-related concussions.

BACKGROUND

An estimated 3.8 million concussions occur each year in the United States as a result of sport and physical activity. Athletic trainers are commonly the first medical providers available onsite to identify and evaluate these injuries.

RECOMMENDATIONS

The recommendations for concussion management provided here are based on the most current research and divided into sections on education and prevention, documentation and legal aspects, evaluation and return to play, and other considerations.

Predicting mild traumatic brain injury patients at risk of persistent symptoms in the Emergency Department

OBJECTIVE

To identify factors that can predict which emergency department (ED) patients with mTBI are likely to develop persistent post-concussion symptoms (PPCS).

DESIGN

A matched case-control study was conducted at a Level 1 trauma centre between June 2006 and July 2009. Patients diagnosed with mTBI in the ED and diagnosed at a concussion management programme with at least one PPCS (85 cases) were compared to patients diagnosed with mTBI in the ED (340 controls) to determine if factors assessed at the time of ED presentation could predict patients likely to develop persistent symptoms.

RESULTS

Multivariable hierarchical logistic regression with variables indicating increased risk for PPCS (prior mTBI, history of depression, history of anxiety, multiple injury, forgetfulness/poor memory, noise sensitivity, or light sensitivity) resulted in a final predictive model including prior mTBI, history of anxiety, forgetfulness/poor memory and light sensitivity. The final model had a specificity of 87.9% and a sensitivity of 69.9%.

CONCLUSIONS

A strong prediction model to identify those ED patients with mTBI at risk for PPCS was developed and could be easily implemented in the ED; therefore, helping to target those patients who would potentially benefit from close follow-up.

Development of the 2012 American Chiropractic Board of Sports Physicians position statement on concussion in athletics

OBJECTIVE

The purpose of this article is to provide a summary of the development of the American Chiropractic Board of Sports Physicians (ACBSP) Position Statement on Concussion in Athletics regarding the management of concussion in sport and to offer suggestions to qualifying doctors of chiropractic (DCs) to make return-to-play decisions and clarify common concepts pertaining to evaluating and managing concussion in sport.

METHODS

A literature review of position statements from sports medicine organizations was performed. The authors reviewed each statement for content. Key issues in the management of concussion in sport were identified with special consideration to concussion management by DCs. A position statement on the management of concussion in sport was drafted by the authors and submitted to the Board of Directors of the ACBSP for review. The Board of Directors called for minor revision; and after all revisions were made, the document was resubmitted. The Board of Directors of the ACBSP accepted the document for publication and presentation. The document was presented and disseminated to certificants by the ACBSP at the 2011 Chiropractic Sports Sciences Symposium.

RESULTS

The 2012 ACBSP Position Statement on Concussion in Athletics was accepted by the ACBSP Board of Directors.

CONCLUSION

The Position Statement on Concussion in Athletics has been accepted by the ACBSP. This document offers guidance on the management of concussion in sport and provides qualifying DCs information to make return-to-play decisions.

A narrative review of sports-related concussion and return-to-play testing with asymptomatic athletes

OBJECTIVE

The purpose of this literature review was to demonstrate, through examples in the current literature, the cumulative and long-term effects of multiple concussions, postinjury protocols, and the efficacy of current and past return-to-play guidelines.

METHODS

A PUBMED SEARCH WAS PERFORMED USING THE KEYWORDS AND KEY PHRASES: concussions and long-term effects, concussions and return to play, and multiple concussions. We limited the search to articles that had been published from August 2007 to August 2012 and were specific to human participants. Of the 450 total articles that the search returned, we selected studies specifically demonstrating athletes who were symptom-free, passed neuropsychological testing, returned to play, and were tested in measures of postural control, transcranial magnetic stimulation, electroencephalographic studies, and magnetic resonance imaging spectroscopy.

RESULTS

Selected studies show evidence that, although a previously concussed athlete may be symptom-free and returned to a neuropsychological baseline, the athlete may continue to have prolonged neurological abnormalities that could disqualify them from being ready to return to play.

CONCLUSION

It appears that some neurological deficits persist beyond the current return-to-play standards and that discrepancy exists between common practices of returning athletes to competition and new standards of published research.

Effect of sex on symptoms and return to baseline in sport-related concussion

OBJECT

Sport-related concussions (SRCs) among youth athletes represent a significant public health concern. Prior research suggests that females fare worse symptomatically after an SRC. The authors aimed to assess sex differences in number, severity, and resolution of postconcussive symptoms using reliable change index (RCI) methodology applied to days to return to symptom baseline.

METHODS

Between 2009 and 2011, 740 youth athletes completed valid neurocognitive and symptom testing before and after an SRC using Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). A total of 122 female and 122 male athletes were matched on number of prior concussions, age, and number of days to first postconcussion test. At baseline and postconcussion, the authors compared each of the individual 22 symptoms on ImPACT to calculate individual symptom severity and aggregate symptom severity, or the Total Symptom Score (TSS). When comparing individual symptoms, the significance level for the comparison of each symptom was set at 0.05/22 = 0.0023. When comparing aggregate symptom severity, or TSS, a single value was compared, requiring an alpha set to 0.05. The number of days to return to baseline TSS was compared using RCI methods set at the 80% confidence interval, equal to a raw score point value of 9.18 on the TSS.

RESULTS

At baseline, females reported a greater severity for the symptom, "sleeping less than usual," compared with males (0.88 ± 1.49 vs 0.31 ± 0.86, p < 0.001). However, no other individual symptom severity differences were noted before or after SRC. At baseline, females exhibited a statistically significant greater aggregate symptom severity than males (7.24 ± 10.22 vs 4.10 ± 6.52, p = 0.005). Greater aggregate symptom severity for females was also found postconcussion (21.38 ± 19.02 vs 16.80 ± 17.07, p = 0.049). Females took longer to return to baseline TSS (9.1 ± 7.1 days vs 7.0 ± 5.1 days, p = 0.013).

CONCLUSIONS

The results of this retrospective study indicate that females endorse a greater severity of symptoms at baseline and postconcussion than males without significantly different symptom profiles. Furthermore, after suffering an SRC, females take longer to return to their baseline symptom level.

Does age affect symptom recovery after sports-related concussion? A study of high school and college athletes

OBJECT

Sport-related concussions (SRCs) in high school and college athletes represent a significant public health concern. Research suggests that younger athletes fare worse symptomatically than older athletes after an SRC. Using reliable change index (RCI) methodology, the authors conducted a study to determine if there are age-related differences in number, severity, and resolution of postconcussion symptoms.

METHODS

Between 2009 and 2011, baseline measures of neurocognitive functions and symptoms in high school and college athletes were entered into a regional database. Seven hundred forty of these athletes later sustained an SRC. Ninety-two athletes in the 13- to 16-year-old group and 92 athletes in the 18- to 22-year-old group were matched for number of prior concussions, sex, biopsychosocial variables, and days to first postconcussion testing and symptom assessment. A nonparametric Mann-Whitney U-test was used to compare the severity of each of 22 symptoms comprising the Total Symptom Scale (TSS) at baseline and first postconcussion test. To obtain a family-wise p value of 0.05 for each test, the significance level for each symptom comparison was set at an alpha of 0.05/22 = 0.0023. The number of days to return to baseline TSS score was compared using the RCI methodology, set at the 80% confidence interval, equal to a change in raw score of 9.18 points on the TSS.

RESULTS

There was no statistically significant difference in symptom presence, symptom severity, and total symptoms between the age groups at baseline or at postconcussion testing. There was no statistically significant difference in return to baseline symptom scores between the age groups.

CONCLUSIONS

Using RCI methodology, there was no statistically significant difference between younger and older athletes in return to baseline symptoms postconcussion.

The Complex Clinical Issues Involved in an Athlete's Decision to Retire from Collision Sport Due to Multiple Concussions: A Case Study of a Professional Athlete

The issue of retirement from athletic participation due to repetitive concussive injuries remains controversial. The complexity of providing recommendations to elite athletes is highlighted by the prospect that offering inappropriate advice may foreseeably lead to engagement in a medico-legal challenge. Currently no evidenced-based, scientifically validated guidelines for forming the basis of such a decision exist. The current paper discusses the complexities of this challenge in addition to presenting a case study of a professional athlete. A number of central issues to consider when discussing athlete retirement revolve around the player’s medical and concussion histories, the current clinical profile, the athlete’s long-term life goals, and understanding of the potential long-term risks. Ensuring that thorough investigations of all possible differential diagnosis, that may explain the presenting symptoms, are conducted is also essential. Discussion pertaining to recommendations for guiding the clinical approach to the retirement issue for athletes with a history of multiple concussions is presented.

Understanding the neuroinflammatory response following concussion to develop treatment strategies

Mild traumatic brain injuries (mTBI) have been associated with long-term cognitive deficits relating to trauma-induced neurodegeneration. These long-term deficits include impaired memory and attention, changes in executive function, emotional instability, and sensorimotor deficits. Furthermore, individuals with concussions show a high co-morbidity with a host of psychiatric illnesses (e.g., depression, anxiety, addiction) and dementia. The neurological damage seen in mTBI patients is the result of the impact forces and mechanical injury, followed by a delayed neuroimmune response that can last hours, days, and even months after the injury. As part of the neuroimmune response, a cascade of pro- and anti-inflammatory cytokines are released and can be detected at the site of injury as well as subcortical, and often contralateral, regions. It has been suggested that the delayed neuroinflammatory response to concussions is more damaging then the initial impact itself. However, evidence exists for favorable consequences of cytokine production following traumatic brain injuries as well. In some cases, treatments that reduce the inflammatory response will also hinder the brain's intrinsic repair mechanisms. At present, there is no evidence-based pharmacological treatment for concussions in humans. The ability to treat concussions with drug therapy requires an in-depth understanding of the pathophysiological and neuroinflammatory changes that accompany concussive injuries. The use of neurotrophic factors [e.g., nerve growth factor (NGF)] and anti-inflammatory agents as an adjunct for the management of post-concussion symptomology will be explored in this review.