Posttraumatic migraine characteristics in athletes following sports-related concussion

Post-traumatic headaches correlate with migraine symptoms in youth with concussion

OBJECTIVE

The term "post-traumatic migraine" (PTM) has been used to describe post-traumatic headaches (PTHs) that have associated migraine features, but studies of this relationship are lacking. The objective of the present study was to determine whether PTH correlates strongly with migraine symptoms among youth with concussion.

METHODS

Twenty-three symptoms were analyzed from a retrospective cohort of 1953 pediatric patients with concussion. A principal component analysis (PCA) with oblique Promax rotation was conducted to explore underlying symptom relationships in the full cohort and in subcohorts stratified by the presence (n = 414) or absence (n = 1526) of premorbid headache.

RESULTS

The mean patient age was 14.1 years; 63% were male. Headache was the most common postconcussion symptom, acknowledged by 69.4% of patients. When considering the full cohort, the PCA demonstrated clustering of headache with photophobia, phonophobia, nausea, dizziness, and neck pain. Similar clustering was present among patients without premorbid headaches. Repeating the analysis in the patients with preconcussion headaches led to elimination of neck pain from the cluster.

CONCLUSIONS

PTH correlates strongly with other migraine symptoms among youth with concussion, regardless of premorbid headaches. This clustering of migraine symptoms supports the existence of PTM as a distinct clinical entity in some patients.

Predictors of postconcussion syndrome after sports-related concussion in young athletes: a matched case-control study

OBJECT Sport-related concussion (SRC) is a major public health problem. Approximately 90% of SRCs in high school athletes are transient; symptoms recover to baseline within 1 week. However, a small percentage of patients remain symptomatic several months after injury, with a condition known as postconcussion syndrome (PCS). The authors aimed to identify risk factors for PCS development in a cohort of exclusively young athletes (9-18 years of age) who sustained SRCs while playing a sport. METHODS The authors conducted a retrospective case-control study by using the Vanderbilt Sports Concussion Clinic database. They identified 40 patients with PCS and matched them by age at injury and sex to SRC control patients (1 PCS to 2 control). PCS patients were those experiencing persistent symptoms at 3 months after an SRC. Control patients were those with documented resolution of symptoms within 3 weeks of an SRC. Data were collected in 4 categories: 1) demographic variables; 2) key medical, psychiatric, and family history; 3) acute-phase postinjury symptoms (at 0-24 hours); and 4) subacute-phase postinjury features (at 0-3 weeks). The chi-square Fisher exact test was used to assess categorical variables, and the Mann-Whitney U-test was used to evaluate continuous variables. Forward stepwise regression models (Pin = 0.05, Pout = 0.10) were used to identify variables associated with PCS. RESULTS PCS patients were more likely than control patients to have a concussion history (p = 0.010), premorbid mood disorders (p = 0.002), other psychiatric illness (p = 0.039), or significant life stressors (p = 0.036). Other factors that increased the likelihood of PCS development were a family history of mood disorders, other psychiatric illness, and migraine. Development of PCS was not predicted by race, insurance status, body mass index, sport, helmet use, medication use, and type of symptom endorsement. A final logistic regression analysis of candidate variables showed PCS to be predicted by a history of concussion (OR 1.8, 95% CI 1.1-2.8, p = 0.016), preinjury mood disorders (OR 17.9, 95% CI 2.9-113.0, p = 0.002), family history of mood disorders (OR 3.1, 95% CI 1.1-8.5, p = 0.026), and delayed symptom onset (OR 20.7, 95% CI 3.2-132.0, p < 0.001). CONCLUSIONS In this age- and sex-matched case-control study of risk factors for PCS among youth with SRC, risk for development of PCS was higher in those with a personal and/or family history of mood disorders, other psychiatric illness, and migraine. These findings highlight the unique nature of SRC in youth. For this population, providers must recognize the value of establishing the baseline health and psychiatric status of children and their primary caregivers with regard to symptom reporting and recovery expectations. In addition, delayed symptom onset was an unexpected but strong risk factor for PCS in this cohort. Delayed symptoms could potentially result in late removal from play, rest, and care by qualified health care professionals. Taken together, these results may help practitioners identify young athletes with concussion who are at a greater danger for PCS and inform larger prospective studies for validation of risk factors from this cohort.

Traumatic axonal injury and persistent emotional lability in an adolescent following moderate traumatic brain injury: A case study

A 15-year-old male was treated secondary to sustaining a moderate traumatic brain injury (moderate TBI). Symptom self-report, and computerized and paper-and-pencil-based neurocognitive, vestibular/ocular motor, and imaging data were used throughout to document impairment and recovery. The patient demonstrated persistent emotional lability concurrent with vestibular impairment. In addition to clinical evaluation and management, the patient also underwent susceptibility-weighted imaging, which revealed axonal shearing across the corpus callosum and areas innervating the prefrontal cortex. Paper-and-pencil neurocognitive measures revealed persisting deficits, despite normal-appearing computerized test results. Implications of this case underline the importance of an integrative evaluation process including clinical interview, neurocognitive and vestibular/ocular physical therapy, and advanced neuroimaging, especially in cases with atypical presentation.

Headache in sports

Sports- and exercise-related headaches are not unusual. Despite their frequent occurrence in this context, there are little epidemiologic data concerning sports-related headache. The recent attention of concussive injuries and associated post-traumatic headache has renewed interest in the study of those headaches occurring after head trauma; however, any primary headache type can also occur in the setting of contact and/or collision sports. The nonspecific nature of headaches provides unique challenges to clinicians encountering this complaint. It is, therefore, imperative that physicians treating athletes are able to distinguish the various headache types and presentations often seen in this population.

The effect of preinjury sleep difficulties on neurocognitive impairment and symptoms after sport-related concussion

BACKGROUND

Researchers have reported that sleep duration is positively related to baseline neurocognitive performance. However, researchers have yet to examine the effect of preinjury sleep difficulties on postconcussion impairments.

PURPOSE

To compare neurocognitive impairment and symptoms of athletes with preinjury sleep difficulties to those without after a sport-related concussion (SRC).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The sample included 348 adolescent and adult athletes (age, mean ± SD, 17.43 ± 2.34 years) with a diagnosed SRC. The sample was divided into 2 groups: (1) 34 (10%) participants with preinjury sleep difficulties (sleeping less as well as having trouble falling asleep; SLEEP SX) and (2) 231 (66%) participants without preinjury sleep difficulties (CONTROL). The remaining 84 (24%) participants with minimal sleep difficulties (1 symptom) were excluded. Participants completed the Immediate Postconcussion Assessment and Cognitive Test (ImPACT) and Postconcussion Symptom Scale (PCSS) at baseline and 3 postinjury intervals (2, 5-7, and 10-14 days after injury). A series of repeated-measures analyses of covariance with Bonferroni correction, controlling for baseline non-sleep-related symptoms, were conducted to compare postinjury neurocognitive performance between groups. Follow-up exploratory t tests examined between-group differences at each time interval. A series of analyses of variance were used to examine total PCSS score, sleep-related, and non-sleep-related symptoms across time intervals between groups.

RESULTS

Groups differed significantly in PCSS scores across postinjury intervals for reaction time (P < .001), with the preinjury SLEEP SX group performing worse than controls at 5-7 days (mean ± SD, 0.70 ± 0.32 [SLEEP SX], 0.60 ± 0.14 [CONTROL]) and 10-14 days (0.61 ± 0.17 [SLEEP SX]; 0.57 ± 0.10 [CONTROL]) after injury. Groups also differed significantly on verbal memory performance (P = .04), with the SLEEP SX (68.21 ± 18.64) group performing worse than the CONTROL group (76.76 ± 14.50) 2 days after injury. The SLEEP SX group reported higher total symptom (P = .02) and sleep-related symptom (P = .02) scores across postinjury time intervals.

CONCLUSION

Preinjury sleep difficulties may exacerbate neurocognitive impairment and symptoms after concussion. The findings may help clinicians identify athletes who are at risk for worse impairments after a concussion due to preinjury sleep difficulties.

Examining postconcussion symptoms of dizziness and imbalance on neurocognitive performance in collegiate football players

OBJECTIVE

This study examined the effects of symptom reports of dizziness and imbalance on cognitive function in concussed collegiate football players.

DESIGN

Retrospective, descriptive.

SETTING

University athletic medicine facility.

SUBJECTS

Twenty-seven collegiate football players were included in the final analysis: 16 with symptoms of dizziness/imbalance resulting from concussion and 11 without dizziness/imbalance resulting from concussion.

MAIN OUTCOME MEASURES

Participants completed the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) at baseline, at 1 to 2 days postconcussion and 5 to 7 days postconcussion. The ImPACT neurocognitive assessment consists of 6 modules, yielding 4 composite scores: verbal memory, visual memory, visual-motor processing speed, and reaction time. In addition, it includes a postconcussion symptom scale total score.

RESULTS

Results revealed that participants with reports of dizziness and imbalance had significantly lower scores on the ImPACT composite scores; however, these individuals also had an overall higher symptom inventory. When accounting for the additional postconcussion symptoms, time was the only significant effect.

CONCLUSION

Dizziness and imbalance are common symptoms postconcussion; however, these symptoms did not predict performance on acute ImPACT scores. Further research is needed to understand the mechanisms causing postconcussion symptoms, including symptoms of dizziness and imbalance, and influence on outcomes postconcussion.

Intravenous migraine therapy in children with posttraumatic headache in the ED

BACKGROUND

More than 3.8 million children sustain traumatic brain injuries annually. Treatment of posttraumatic headache (PTH) in the emergency department (ED) is variable, and benefits are unclear.

OBJECTIVE

The objective of the study is to determine if intravenous migraine therapy reduces pain scores in children with PTH and factors associated with improved response.

METHODS

This was a retrospective study of children, 8 to 21 years old, presenting to a tertiary pediatric ED with mild traumatic brain injury (mTBI) and PTH from November 2009 to June 2013. Inclusion criteria were mTBI (defined by diagnosis codes) within 14 days of ED visit, headache, and administration of one or more intravenous medications: ketorolac, prochlorperazine, metoclopramide, chlorpromazine, and ondansetron. Primary outcome was treatment success defined by greater than or equal to 50% pain score reduction during ED visit. Bivariate analysis and logistic regression were used to determine predictors of treatment success: age, sex, migraine or mTBI history, time since injury, ED head computed tomographic (CT) imaging, and pretreatment with oral analgesics.

RESULTS

A total of 254 patients were included. Mean age was 13.8 years, 51% were female, 80% were white, mean time since injury was 2 days, and 114 patients had negative head CTs. Eighty-six percent of patients had treatment success with 52% experiencing complete resolution of headache. Bivariate analysis showed that patients who had a head CT were less likely to respond (80% vs 91%; P = .008).

CONCLUSIONS

Intravenous migraine therapy reduces PTH pain scores for children presenting within 14 days after mTBI. Further prospective work is needed to determine long-term benefits of acute PTH treatment in the ED.

Factors Influencing Risk and Recovery from Sport-Related Concussion: Reviewing the Evidence

Identifying factors that influence the risk and recovery from sport-related concussion (SRC) has become an important part of the clinical management of the injury. Consensus statements and clinical anecdotes have suggested several factors (i.e., history of migraine headaches) that may increase risk or lead to a protracted recovery from SRC. In the current paper, we will present evidence supporting primary and secondary risk factors listed in current consensus statements and relevant literature on emerging factors proposed to influence SRC risk and recovery.

Return-to-play guidelines in concussion: revisiting the literature

Return-to-play (RTP) guidelines in concussion management and treatment continue to challenge clinicians, despite recent updates to the protocols and the ongoing media attention. The current guidelines address individualized treatment planning but are difficult to apply to athletes who experience prolonged symptoms, are younger, or have sustained multiple concussions. Recent literature findings have contributed to an improved understanding and applicability of the guidelines while emphasizing a multidisciplinary paradigm in formulating an individualized RTP decision. Successful implementation of the RTP guidelines will ensure that athletes are protected from further injury and return to their baseline functional status.

Traumatic migraine versus concussion: a case report

Context:

An era of increased awareness of sports concussions may decrease a provider’s ability to diagnose the athlete’s actual condition and may ultimately prolong the restriction of the injured athlete from sports. Trauma-triggered migraine is a source of headaches, especially in athletes with a family history of migraines.

Evidence Acquisition:

Research articles were primarily obtained through the electronic database PubMed from 1993 to August 2012. Primary research parameters included trauma-induced headaches, trauma-induced migraines, and posttraumatic migraine. The secondary search parameters included concussions, migraine treatments, and traumatic migraine treatments.

Study Design:

Clinical review with case report.

Level of Evidence:

Level 5.

Results:

There are no symptoms that distinguish trauma-triggered migraines from concussions, as headache is the most common complaint for both conditions. There is a paucity of studies that offer treatment guidelines for athletes with recurring headaches after trauma sustained during sporting events. Preventive treatment of migraines has been validated and proven effective.

Conclusion:

Trauma-triggered migraine should be considered in the differential for recurrent trauma-induced headaches. There is a lack of research evaluating efficacy and side effects of treatment of trauma-triggered migraine, and no information was found directing when an athlete can safely return to play.

Duration and course of post-concussive symptoms

OBJECTIVES

To examine the incidence, duration, and clinical course of individual post-concussive symptoms in patients presenting to a pediatric emergency department (ED) with a concussion.

METHODS

We conducted secondary analysis of a prospective cohort study of patients 11 to 22 years old presenting to the ED of a children's hospital with an acute concussion. The main outcome measure was duration of symptoms, assessed by the Rivermead Post-Concussion Symptoms Questionnaire (RPSQ). Patients initially completed a questionnaire describing mechanism of injury, associated symptoms, past medical history, and the RPSQ, then were serially administered the RPSQ for 3 months after the concussion or until all symptoms resolved.

RESULTS

Headache, fatigue, dizziness, and taking longer to think were the most common symptoms encountered at presentation, whereas sleep disturbance, frustration, forgetfulness, and fatigue were the symptoms most likely to develop during the follow-up period that had not initially been present. Median duration of symptoms was the longest for irritability (16 days), sleep disturbance (16 days), frustration (14 days), and poor concentration (14 days), whereas nausea, depression, dizziness, and double-vision abated most quickly. One month after injury, nearly a quarter of children still complained of headache, >20% suffered from fatigue, and nearly 20% reported taking longer to think.

CONCLUSIONS

Among patients presenting to a pediatric ED after a concussion, physical symptoms such as headache predominate immediately after the injury, emotional symptoms tend to develop later in the recovery period, and cognitive symptoms may be present throughout.

Use of modified acute concussion evaluation tools in the emergency department

OBJECTIVES

Accurate recognition of pediatric concussion in the emergency department (ED) is important to ensure appropriate management for safe recovery. The study objective was to determine whether the Centers for Disease Control and Prevention's Acute Concussion Evaluation (ACE) tools, modified for ED use, improved patient follow-up and post-injury behaviors.

METHODS

The original ACE tools (ACE, ACE Care Plan) were modified for ED use via Delphi methodology with an expert panel and implemented in 2 urban pediatric EDs for patients aged 5 to 21 years evaluated within 24 hours of a head injury. Pre- (February 2009 to July 2009) and post- (December 2009 to June 2010) implementation, patient phone surveys were conducted 1, 2, and 4 weeks after ED discharge. Reported rates of patient follow-up and recovery measures were analyzed. ED clinician adherence was assessed.

RESULTS

During the study, 164 patients were enrolled pre-implementation and 190 post-implementation. The mean patient age was 10.6 years (SD, 3.7); 65% were males, 49% were African American, and 46% were Caucasian. Post-implementation, 58% of patients received the modified ACE diagnostic tool and 84% received the modified ACE discharge instructions. Follow-up was improved at all time points (32% vs 61% at week 4; P < .001; odds ratio, 3.4; 95% confidence interval, 2.1-5.4). Post-implementation, parental recall of discharge instructions was significantly increased, patient's mean total post-concussion symptom score was significantly higher, and report of return to normal activity was significantly longer.

CONCLUSIONS

The ACE tools, modified for ED use, were successfully implemented in the pediatric ED. Post-implementation, increased patient follow-up and improved recall of and adherence to ED discharge recommendations was demonstrated.

Posttraumatic headaches in civilians, soldiers, and athletes

Posttraumatic headaches are one of the most common and controversial secondary headache types. After mild head injury, more than 50% of people develop a postconcussion syndrome which has been controversial for more than 150 years. Headache is estimated as present in 30% to 90% of patients after mild head injury. Most headaches are of the tension type, although migraines can increase in frequency or occur acutely or chronically de novo. A review is provided of headaches in civilians, soldiers after blast trauma, athletes, and post-craniotomy including pathogenesis. The treatments are the same as for the primary phenotypes.

Risk modifiers for concussion and prolonged recovery

Context:

Currently, no consensus exists for grading the severity of concussions. Identification of risk factors that may affect concussion risk and the likelihood of prolonged recovery can be of value to providers who manage concussion.

Evidence Acquisition:

Relevant studies were identified through MEDLINE (1996-2011) using the keywords concussion, postconcussive syndrome, and risk or risk factor. Targeted searches for specific risk factors were conducted with additional keywords, such as gender and migraine. Manual review of reference lists was also performed to identify pertinent literature.

Results:

For risk factors of concussion, history of prior concussion and female sex have the most supporting evidence. Sports with consistently high risk for sustaining a concussion include football, men’s ice hockey, and women’s soccer. Younger athletes appear to be more susceptible to concussion, but data are limited and inconsistent. Protective equipment does not definitively alter concussion risk, though it protects against other injuries. Symptoms such as long headaches, migraines, amnesia, and multiple symptoms appear to be associated with prolonged recovery. Younger age may also increase the risk of prolonged concussion.

Conclusion:

High-quality evidence for risk modifiers in concussion remains sparse. Prior concussion, collision sports, female sex, and women’s soccer are the strongest known risk factors. Evidence for most other factors is inconclusive.

Trends in concussion return-to-play timelines among high school athletes from 2007 through 2009

CONTEXT

Whereas guidelines about return-to-play (RTP) after concussion have been published, actual prognoses remain elusive.

OBJECTIVE

To develop probability estimates for time until RTP after sport-related concussion.

DESIGN

Descriptive epidemiology study.

SETTING

High school.

PATIENTS OR OTHER PARTICIPANTS

Injured high school varsity, junior varsity, or freshman athletes who participated in 1 of 13 interscholastic sports at 7 area high schools during the 2007-2009 academic years.

INTERVENTION(S)

Athletic trainers employed at each school collected concussion data. The athletic trainer or physician on site determined the presence of a concussion. Athlete-exposures for practices and games also were captured.

MAIN OUTCOME MEASURE(S)

Documented concussions were categorized by time missed from participation using severity outcome intervals (same-day return, 1- to 2-day return, 3- to 6-day return, 7- to 9-day return, 10- to 21-day return, >21-day return, no return [censored data]). We calculated Kaplan-Meier time-to-event probabilities that included censored data to determine the probability of RTP at each of these time intervals.

RESULTS

A total of 81 new concussions were documented in 478 775 athlete-exposures during the study period. After a new concussion, the probability of RTP (95% confidence interval) was 2.5% (95% confidence interval = 0.3, 6.9) for a 1- to 2-day return, 71.3% (95% confidence interval = 59.0, 82.9) for a 7- to 9-day return, and 88.8% (95% confidence interval = 72.0, 97.2) for a 10- to 21-day return.

CONCLUSIONS

For high school athletes, RTP within the first 2 days after concussion was unlikely. After 1 week, the probability of return rose substantially (approximately 71%). Prognostic indicators are used to educate patients about the likely course of disease. Whereas individual symptoms and recovery times vary, prognostic time-to-event probabilities allow clinicians to provide coaches, parents, and athletes with a prediction of the likelihood of RTP within certain timeframes after a concussion.

Recovery of posttraumatic migraine characteristics in patients after mild traumatic brain injury

BACKGROUND

Headache-related symptoms may be predictive of delayed recovery in student athletes after sport-related concussion. PURPOSE AND HYPOTHESIS: To compare balance performance, cognitive function, and symptom recovery in concussed student athletes with no headache, those with posttraumatic headache, and those with characteristics of posttraumatic migraine following a sport-related concussion. It was hypothesized that those with posttraumatic migraine would take longer to recover on all clinical measures.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

A total of 296 student athletes who sustained sport-related concussions (migraine, 52; headache, 176; no headache, 68) were evaluated on measures of balance performance, cognition, and symptoms. Patients were categorized into posttraumatic migraine, posttraumatic headache, and no headache groups based on symptoms reported 1 day after injury. Serial testing was conducted with the Balance Error Scoring System, the Standardized Assessment of Concussion, and a graded symptom checklist to evaluate balance performance, cognition, and symptoms, respectively, at baseline, at the time of injury, after the event, and at days 1, 2, 3, 5, 7, and 90.

RESULTS

Student athletes with posttraumatic migraine experienced greater symptom severity scores than did those with posttraumatic headache and no headache at the time of injury, after the event, and through day 7 (P < .001 for all). By day 7, symptom severity scores reported by patients with posttraumatic migraine still demonstrated deficits relative to baseline (Δ = 5.6 ± 1.2) compared with patients with headache (Δ = -0.8 ± 0.7) and those with no headache (Δ = -1.4 ± 1.1). Patients with headache experienced greater symptom severity scores than patients with no headache at the time of injury (P < .001), after the event (P < .001), and at day 1 (P < .001), day 2 (P = .005), and day 3 (P = .038). Much smaller differences were observed between the headache and no headache groups beyond day 3 (P > .05). There were no group differences on balance performance (P = .439) and cognitive testing (P = .200) over time. Female patients were 2.13 times more likely than males to report posttraumatic migraine characteristics after concussion.

CONCLUSION

Posttraumatic migraine characteristics are related to prolonged symptom recovery after sport-related concussion. Clinicians should exercise caution in making decisions about return to participation for athletes with migraine-like symptoms given the increased short-term impairments and delayed symptom recovery we observed.

Posttraumatic migraine as a predictor of recovery and cognitive impairment after sport-related concussion

BACKGROUND

Although previous research has demonstrated that patients with posttraumatic migraine (PTM) after concussion report more symptoms and cognitive deficits after injury than do those without PTM, it is not known whether these effects persist beyond the first week of injury or whether PTM predicts recovery time.

PURPOSE

To determine whether PTM during the first week after injury predicts (1) cognitive impairment and symptoms in the second week after injury and (2) overall recovery time.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Participants were 138 male high school football players with a mean age of 15.96 years (SD, 1.18 years; range, 13-19 years). They were classified into 3 groups: PTM (headache, nausea, and photosensitivity or phonosensitivity), headache (headache without the other PTM symptoms), or no headache (no headache or PTM symptoms). The Immediate Post-concussion Assessment and Cognitive Test (ImPACT) was used to assess cognitive performance and symptoms at baseline, postinjury days 1-7, and postinjury days 8-14. Recovery time data were collected from medical records.

RESULTS

The PTM group performed worse on verbal memory than did the headache group at 8-14 days after injury. The PTM group performed worse on visual memory, reaction time, and symptoms than did the other groups at 1-7 days and 8-14 days after injury. The PTM group was 7.3 times (95% confidence interval, 1.80-29.91) more likely to have protracted recovery (>20 days) than the no headache group and 2.6 times (95% confidence interval, 1.10-6.54) more likely than the headache group.

CONCLUSION

Results suggest that PTM is associated with cognitive impairments and protracted recovery and that headache alone is not a good predictor of recovery.

Impaired cerebral haemodynamic function associated with chronic traumatic brain injury in professional boxers

The present study examined to what extent professional boxing compromises cerebral haemodynamic function and its association with CTBI (chronic traumatic brain injury). A total of 12 male professional boxers were compared with 12 age-, gender- and physical fitness-matched non-boxing controls. We assessed dCA (dynamic cerebral autoregulation; thigh-cuff technique and transfer function analysis), CVRCO₂ (cerebrovascular reactivity to changes in CO₂: 5% CO₂ and controlled hyperventilation), orthostatic tolerance (supine to standing) and neurocognitive function (psychometric tests). Blood flow velocity in the middle cerebral artery (transcranial Doppler ultrasound), mean arterial blood pressure (finger photoplethysmography), end-tidal CO₂ (capnography) and cortical oxyhaemoglobin concentration (near-IR spectroscopy) were continuously measured. Boxers were characterized by fronto-temporal neurocognitive dysfunction and impaired dCA as indicated by a lower rate of regulation and autoregulatory index (P<0.05 compared with controls). Likewise, CVRCO₂ was also reduced resulting in a lower CVRCO₂ range (P<0.05 compared with controls). The latter was most marked in boxers with the highest CTBI scores and correlated against the volume and intensity of sparring during training (r=-0.84, P<0.05). These impairments coincided with more marked orthostatic hypotension, cerebral hypoperfusion and corresponding cortical de-oxygenation during orthostatic stress (P<0.05 compared with controls). In conclusion, these findings provide the first comprehensive evidence for chronically impaired cerebral haemodynamic function in active boxers due to the mechanical trauma incurred by repetitive, sub-concussive head impact incurred during sparring training. This may help explain why CTBI is a progressive disease that manifests beyond the active boxing career.

Sport-related concussion: "how many is too many?"

The long-term effects of multiple sport-related concussions are currently at the center of debate in the popular press and scientific community. The question, "How many concussions are too many," is frequently asked in the competitive sport environment by parents, athletes, and coaches. While research suggests that a history of concussion influences the risk and recovery from subsequent concussion, studies investigating the long-term effects of multiple concussions are less conclusive. This paper reviews the literature on multiple concussions and the potential long-term consequences of these injuries. Furthermore, this paper addresses how concussion history can inform clinical and return-to-play decisions. Recent studies incorporating novel brain imaging and electrophysiological technology for assessing residual impairment from multiple concussions are reviewed and the clinical implications of this work are discussed.

Subacute concussion-related symptoms and postconcussion syndrome in pediatrics

PURPOSE OF REVIEW

Millions of youth sustain concussion each year; although most fully recover following an isolated concussion, a significant minority develop prolonged symptoms and disability following concussion. This article reviews recent data regarding the epidemiology of postconcussion syndrome (PCS) and recommendations for the evaluation and management of postconcussive symptoms in pediatrics.

RECENT FINDINGS

PCS is a constellation of symptoms related to head injury including somatic symptoms, sleep dysregulation, cognitive deficits and emotional disturbance. Postconcussive symptoms affect 1.5-11% of concussed youth for more than 1 month after injury, depending on the population studied. Girls have a higher risk of postconcussive headache but it is not clear if cognitive recovery differs between the sexes. Advanced neuroimaging techniques demonstrate a correlation between postconcussive symptoms and functional neurological changes. However, pre-existing and psychosocial factors also affect risk for prolonged PCS. Current treatment strategies are based mainly on expert opinion and studies of related syndromes.

SUMMARY

Although a minority of concussed youth develop prolonged PCS, those who are affected can develop significant disability. Prolonged postconcussive symptoms are likely due to interactions between the biological injury, pre-existing risk factors and psychosocial issues. Further research is essential to improve outcomes for this vulnerable population.

The young brain and concussion: imaging as a biomarker for diagnosis and prognosis

Concussion (mild traumatic brain injury (mTBI)) is a significant pediatric public health concern. Despite increased awareness, a comprehensive understanding of the acute and chronic effects of concussion on central nervous system structure and function remains incomplete. Here we review the definition, epidemiology, and sequelae of concussion within the developing brain, during childhood and adolescence, with current data derived from studies of pathophysiology and neuroimaging. These findings may contribute to a better understanding of the neurological consequences of traumatic brain injuries, which in turn, may lead to the development of brain biomarkers to improve identification, management and prognosis of pediatric patients suffering from concussion.

Subacute concussion-related symptoms in youth

Most athletes who experience a sports-related concussion recover from the acute effects within a few weeks. However, some children and adolescents with concussion experience symptoms for many weeks, or even months after the injury. Subacute and chronic symptoms related to concussion are particularly concerning in children, because cognitive deficits, headache or neck pain, sleep dysfunction, and emotional dysregulation can affect school performance and social function at a critical period of development and maturation. This article reviews the epidemiology of subacute symptoms after pediatric concussion and the current recommendations for the assessment and management of these symptoms in children and adolescents.

School and the concussed youth: recommendations for concussion education and management

School learning and performance is arguably the critical centerpiece of child and adolescent development, and there can be significant temporary upset in cognitive processing after a mild traumatic brain injury, also called a concussion. This injury results in a cascade of neurochemical abnormalities, and, in the wake of this dysfunction, both physical and cognitive activities become sources of additional neurometabolic demand on the brain and may cause symptoms to reemerge or worsen. This article provides a foundation for postinjury management of cognitive activity, particularly in the school setting, including design and implementation of schoolwide concussion education and management programs.

Return-to-play guidelines in concussion: a closer look at the literature

Traumatic brain injuries that occur during sports have gained significant attention in the literature. Despite improved education and research on proper identification, risk management, and treatment, standardized methods for returning an athlete to play after a concussion are lacking in universal applicability. Current return-to-play guidelines are considered appropriate for the majority of athletes who recover within a few weeks. However, applicability of such guidelines becomes difficult when treating those athletes who experience prolonged symptoms or do not have the resources available to adequately manage complex presentations of concussions. Understanding the guidelines with consideration to special populations will assist the treating physician in providing an appropriate and individualized evaluation and treatment plan to safely return an athlete with a concussion back to play without compromising his or her health.

Sensitivity and specificity of subacute computerized neurocognitive testing and symptom evaluation in predicting outcomes after sports-related concussion

BACKGROUND

Concussions affect an estimated 136 000 high school athletes yearly. Computerized neurocognitive testing has been shown to be appropriately sensitive and specific in diagnosing concussions, but no studies have assessed its utility to predict length of recovery. Determining prognosis during subacute recovery after sports concussion will help clinicians more confidently address return-to-play and academic decisions.

PURPOSE

To quantify the prognostic ability of computerized neurocognitive testing in combination with symptoms during the subacute recovery phase from sports-related concussion.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

In sum, 108 male high school football athletes completed a computer-based neurocognitive test battery within 2.23 days of injury and were followed until returned to play as set by international guidelines. Athletes were grouped into protracted recovery (>14 days; n = 50) or short-recovery (≤14 days; n = 58). Separate discriminant function analyses were performed using total symptom score on Post-Concussion Symptom Scale, symptom clusters (migraine, cognitive, sleep, neuropsychiatric), and Immediate Postconcussion Assessment and Cognitive Testing neurocognitive scores (verbal memory, visual memory, reaction time, processing speed).

RESULTS

Multiple discriminant function analyses revealed that the combination of 4 symptom clusters and 4 neurocognitive composite scores had the highest sensitivity (65.22%), specificity (80.36%), positive predictive value (73.17%), and negative predictive value (73.80%) in predicting protracted recovery. Discriminant function analyses of total symptoms on the Post-Concussion Symptom Scale alone had a sensitivity of 40.81%; specificity, 79.31%; positive predictive value, 62.50%; and negative predictive value, 61.33%. The 4 symptom clusters alone discriminant function analyses had a sensitivity of 46.94%; specificity, 77.20%; positive predictive value, 63.90%; and negative predictive value, 62.86%. Discriminant function analyses of the 4 computerized neurocognitive scores alone had a sensitivity of 53.20%; specificity, 75.44%; positive predictive value, 64.10%; and negative predictive value, 66.15%.

CONCLUSION

The use of computerized neurocognitive testing in conjunction with symptom clusters results improves sensitivity, specificity, positive predictive value, and negative predictive value of predicting protracted recovery compared with each used alone. There is also a net increase in sensitivity of 24.41% when using neurocognitive testing and symptom clusters together compared with using total symptoms on Post-Concussion Symptom Scale alone.

Postconcussive symptoms are associated with compensatory cortical recruitment during a working memory task

BACKGROUND

The severity of sports-related concussion is often characterized by the number and severity of postconcussive symptoms (eg, headache, dizziness, difficulty concentrating). Although the level of postconcussive symptoms after injury is believed to index the severity of the neurological insult sustained, studies examining the relationship between symptom severity and neural functioning in concussed athletes remain rare.

OBJECTIVE

This exploratory study examined the association between self-reported symptom severity and functional activation on a working memory task in a group of 16 recently concussed student athletes.

METHODS

Functional magnetic resonance imaging was used to examine the relationship of symptom severity to brain activation during a working memory task in 16 concussed subjects.

RESULTS

Findings indicated that symptom severity was associated with regionally specific hyperactivation during a working memory task, even though symptom severity was not significantly related to task accuracy.

CONCLUSION

The results add to a growing body of literature that demonstrates that functional neuroimaging may have the potential to serve as a sensitive biomarker of the severity of concussion and mild traumatic brain injury.

Cerebrovascular pathophysiology following mild traumatic brain injury

Mild traumatic brain injury (mTBI) or sport-induced concussion has recently become a prominent concern not only in the athletic setting (i.e. sports venue) but also in the general population. The majority of research to date has aimed at understanding the neurological and neuropsychological outcomes of injury as well as return-to-play guidelines. Remaining relatively unexamined has been the pathophysiological aspect of mTBI. Recent technological advances including transcranial Doppler ultrasound and near infrared spectroscopy have allowed researchers to examine the systemic effects of mTBI from rest to exercise, and during both asymptomatic and symptomatic conditions. In this review, we focus on the current research available from both human and experimental (animal) studies surrounding the pathophysiology of mTBI. First, the quest for a unified definition of mTBI, its historical development and implications for future research is discussed. Finally, the impact of mTBI on the control and regulation of cerebral blood flow, cerebrovascular reactivity, cerebral oxygenation and neuroautonomic cardiovascular regulation, all of which may be compromised with mTBI, is discussed.

Concussion management and treatment considerations in the adolescent population

Over the past decade, significant advances have been made in understanding concussions. Information regarding proper identification, pathophysiology, risks, outcomes, and management protocols has shifted the treatment paradigm from a generalized grading system to an individualized approach. Early identification and timely management of a concussion is necessary to ensure that patients minimize persistent post-concussive symptoms affecting the physical, behavioral, emotional, and cognitive domains. Adolescents are particularly vulnerable to concussions, having greater susceptibility and more prolonged recovery after sustaining an injury. This article aims to inform clinicians on how to improve symptom relief and functional outcomes for adolescent patients with concussion via immediate intervention, neuropsychological management, and pharmacological treatment.